• Korean journal of applied entomology
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• v.61 no.3
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• pp.399-408
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• 2022

There has been much debate on the morphometric divergence between the recently identified Apis cerana koreana and Apis cerana honey bees. The aim of this study was to obtain phenotypic information that can be used to compare A. c. koreana data with other A. cerana subspecies data from open resources and determine breeding results on the basis of morphometric traits. To differentiate A. c. koreana, we investigated 22 classic morphological characteristics; royal jelly secretion; and the weight of workers, queens, and drones of A. c. koreana bred in Korea. To define the selection results, we used the geometric morphometric method. The artificially selected A. c. koreana secreted significantly more royal jelly (1.18 times) than the naturally selected A. c. koreana, which positively influenced the health of the colonies. These honey bees were identified more clearly with the geometric morphometric method than with the classic morphometric method, which is traditionally used to determine the subspecies. Large trends were noted for A. c. koreana on the basis of our results and literature from the 1980s regarding A. cerana sizes in Korea (tarsal index, length of forewing, and cubital index were measured). The cluster analysis revealed the proximity of A. c. koreana, A. cerana in China, and A. c. indica on the basis of eight classic characters, which, perhaps, relay the origin of the honey bees. The results of this study defined the morphometric responses of A. c. koreana honey bees to geographic isolation, climate change, and selection, which are important to identify, protect, and preserve honey bee stock in Korea.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.423-434
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• 2022

The two previously developed artificial diets (N4 and N6) used for rearing Spodoptera frugiperda (Noctuidae) larvae, were selected as highly-fit ones for rearing Mythimna loreyi larvae. Almost all biological characteristics were not significantly different between the colonies reared on the two diets at 25℃ and 15:9 h (light:dark) photoperiod. The developmental periods were 4.9-5.2 days for eggs, and 22.3-23.2 days for larvae. The pupal period and weight were different between the sexes in each diet colony. The pupal periods in females and males showed 12.6-12.8 days and 14.1-14.5 days, respectively. The pupal weights were ca. 345 mg for females and ca. 380 mg for males. The pupation and emergence rates were ca. 91-94%, and ca. 91-95%, respectively, without significant differences between the two colonies. The pre-oviposition and oviposition periods were 3.4 days and 4.7-4.8 days, respectively. The adult longevity was 8.2 days in females and 10.3-12.4 days in males. Total offsprings produced were found to be 724-847 larvae on an average with ca. 1,400 maximum larvae. In the life table analysis, the intrinsic rates of increases (0.1181 for N4 and 0.1253 for N6) were not significantly different between the two colonies. Individual differences in the larval instar number 5 and 6 were found within a diet colony. The ratios of 5-instar larvae were ca. 22% in N4 colony and ca. 7% in N6 colony. The larval period of 6-instar larvae was longer than that of 5-instar larvae. Width of head capsule in larvae varied from ca. 309 ㎛ for 1st instar to ca. 3,065 ㎛ for 6th instar. Body lengths measured from ca. 2.0 mm for 1st instar to ca. 29.1 mm for 6th instar. Larvae of M. loreyi and M. separata were found at the same time in a maize field during June and July, 2020.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.409-422
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• 2022

Two dominant thrips in hot pepper (Capsicum annuum) cultivating in greenhouses are Frankliniella occidentalis and F. intonsa in Korea. This study investigated their overwintering physiology. These two thrips were freeze-susceptible and suppressed the body freezing temperature by lowering supercooling point (SCP) down to -15~-27℃. However, these SCPs varied among species and developmental stages. SCPs of F. occidentalis were -25.7±0.5℃ for adults, -17.2±0.3℃ for pupae, and -15.0±0.4℃ for larvae. SCPs of F. intonsa were -24.0±1.0℃ for adults, -27.0±0.5℃ for pupae, -17.2±0.8℃ for larvae. Cold injuries of both species occurred at low temperature treatments above SCPs. Thrips mortality increased as the treatment temperature decreased and its exposure period increased. F. occidentalis exhibited higher cold tolerance than F. intonsa. In both species, adults were more cold-tolerant than larvae. Two thrips species exhibited a rapid cold hardening because a pre-exposure to 0℃ for 2 h significantly enhanced the cold tolerance to a lethal cold temperature treatment at -10℃ for 2 h. In addition, a sequential exposure of the thrips to decreasing temperatures made them to be acclimated to low temperatures. To investigate the overwintering sites of the two species, winter monitoring of the thrips was performed at the greenhouses. During winter season (November~February), adults of the two species were not captured in outside of the greenhouses. However, F. occidentalis adults were captured to the traps and observed in weeds within the greenhouses. F. occidentalis adults were also emerged from soil samples obtained from the greenhouses during the winter season. F. intonsa adults did not come out from the soil samples at November and December, but emerged from the soil samples obtained after January. To determine the adult emergence due to diapause development, two thrips species were reared under different photoperiods. Adult development occurred in all photoperiod treatments in F. occidentalis, but did not in F. intonsa especially under short periods. Tomato spotted wilt virus, which is transmitted by these two species, was detected in the weeds infested by the thrips during the winter season. These results suggest that F. occidentalis develops on weeds in the greenhouses while F. intonsa undergoes a diapause in the soil during winter.

• Journal of the Korean Applied Science and Technology
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• v.40 no.1
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• pp.13-23
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• 2023

This study is an experimental study on the single group pre-post test design for the effects of the aroma inhalation method with roll-on on stress, pain, depression and blood pressure of the elderly. 33 elderly people who met the selection criteria participated among the elderly using the senior citizen clubs located in S city, Gyeonggi-do. The data collection period was from November 14, 2022 to December 19, 2022. A questionnaire consisting of stress, pain, depression, and blood pressure was measured before and after the aroma roll-on inhalation intervention. The components of aroma essential oil included Marjoram, Geranium, Peppermint and Orange sweet that were diluted in Jojoba oil which was the carrier oil. The aroma inhalation method with roll-on was carried out 3 times day for 4 weeks. In the result of this study, the aroma inhalation method with roll-on were statistically significant differences in stress(t=2.63, p=.013), pain(t=2.46, p=.019), and systolic blood pressure(t=3.01, p=.005) of the participants. Therefore, aroma roll-on therapy is expected to be available as a useful nursing intervention method for reducing stress, relieving pain, and managing blood pressure in the elderly using the senior citizen clubs.

• Journal of Species Research
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• v.12 no.spc
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• pp.1-69
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• 2023

This study aims to establish a comprehensive, synthetic inventory system for the fauna and flora of Dokdo Island, Republic of Korea, which has been conducted by a specialized research group consisting of more than 50 experts. The research was conducted over five years(2015-2019) and supported by the National Institute of Biological Resources, Ministry of Environment, Republic of Korea. All possible publications on the fauna and flora of Dokdo Island over the last 68 years from 1952 to 2020 were reviewed. As a result, 1,302 species were found on Dokdo Island during the study period. An updated list of 1,963 species was created. This is expected to be of great help for the conservation and national publicity of important indigenous biological resources of Dokdo Island.

• Journal of Life Science
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• v.33 no.5
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• pp.391-396
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• 2023

Milk is an emulsion, improving texture of surimi mixture and able to suppress off flavors and abnormal tastes. Therefore, this study aimed to identify the effective properties of milk in the preparation of a surimi mixture for 3D printing. The sensory and physical properties of surimi mixtures containing 0%, 20 wt%, and 40 wt% milk were evaluated, where the unheated surimi mixture with added milk demonstrated increased firmness and adhesiveness compared to the negative control group. In addition, the hardness, adhesiveness, gumminess, and chewiness of the mixture containing 40% milk were highest, but springiness, cohesiveness, and resilience were lowest. In the sensory evaluation, as the amount of milk increased, a fishy smell, abnormal taste and texture improved, hardness and preference increased as well. From these results, it was confirmed that a surimi mixture can be prepared with milk to improve its physical and sensory properties for 3D printing when compared to the negative control mixture. In particular, it was revealed that the physical properties and preference of the surimi mixture are best when prepared with 40% milk.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.1
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• pp.17-27
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• 2023

Weeds are one of the factors that reduce crop yield through nutrient and photosynthetic competition. Quantification of weed density are an important part of making accurate decisions for precision weeding. In this study, we tried to quantify the density of weeds in images of maize fields taken by unmanned aerial vehicle (UAV). UAV image data collection took place in maize fields from May 17 to June 4, 2021, when maize was in its early growth stage. UAV images were labeled with pixels from maize and those without and the cropped to be used as the input data of the semantic segmentation network for the maize detection model. We trained a model to separate maize from background using the deep learning segmentation networks DeepLabV3+, U-Net, Linknet, and FPN. All four models showed pixel accuracy of 0.97, and the mIOU score was 0.76 and 0.74 in DeepLabV3+ and U-Net, higher than 0.69 for Linknet and FPN. Weed density was calculated as the difference between the green area classified as ExGR (Excess green-Excess red) and the maize area predicted by the model. Each image evaluated for weed density was recombined to quantify and visualize the distribution and density of weeds in a wide range of maize fields. We propose a method to quantify weed density for accurate weeding by effectively separating weeds, maize, and background from UAV images of maize fields.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.1
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• pp.28-36
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• 2023

Solar radiation that is measured at relatively small number of weather stations is one of key inputs to crop models for estimation of crop productivity. Solar radiation products derived from GK-2A and Himawari 8 satellite data have become available, which would allow for preparation of input data to crop models, especially for assessment of crop productivity under an agrivoltaic system where crop and power can be produced at the same time. The objective of this study was to compare the degree of agreement between the solar radiation products obtained from those satellite data. The sub hourly products for solar radiation were collected to prepare their daily summary for the period from May to October in 2020 during which both satellite products for solar radiation were available. Root mean square error (RMSE) and its normalized error (NRMSE) were determined for daily sum of solar radiation. The cumulative values of solar radiation for the study period were also compared to represent the impact of the errors for those products on crop growth simulations. It was found that the data product from the Himawari 8 satellite tended to have smaller values of RMSE and NRMSE than that from the GK-2A satellite. The Himawari 8 satellite product had smaller errors at a large number of weather stations when the cumulative solar radiation was compared with the measurements. This suggests that the use of Himawari 8 satellite products would cause less uncertainty than that of GK2-A products for estimation of crop yield. This merits further studies to apply the Himawari 8 satellites to estimation of solar power generation as well as crop yield under an agrivoltaic system.

• Korean Journal of Environment and Ecology
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• v.37 no.1
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• pp.1-12
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• 2023

We analyzed the distribution area of debris slopes in Mudeungsan (Mt. Mudeung) National Park by comparing aerial photos of the past (1966) and the present (2017) and identified the vegetation characteristics that affect the change in the area of the debris slopes by investigating the vegetation status of the debris slopes and the surrounding areas. The area of debris slopes in Mt. Mudeung appears to have been reduced to a quarter of what it used to be. Debris slopes here have decreased at an average rate of 2.3 ha/yr over 51 years by vegetation covers. Notably, most of the small-area debris slopes in the low-inclination slopes disappeared due to active vegetation coverage. However, there are still west-facing, south-west-facing, south-facing, and large-area debris slopes remaining because the sun's radiant heat rapidly raises the surface temperature of rock blocks and dries moisture, making tree growth unfavorable. Because of these locational characteristics, the small-scale vegetation in the middle of Deoksan Stony Slope, which is the broadest area, showed distinct characteristics from the adjacent forest areas. Sunny places and tree species with excellent drying resistance were observed frequently in Deoksan Stony Slope. However, tree species with high hygropreference that grow well in valleys with good soil conditions also prevailed. In some of these places, the soil layer has been well developed due to the accumulation of fine materials and organic matter between the crevices of the rock blocks, which is likely to have provided favorable conditions for such tree species to settle and grow. At the top of Mt. Mudeung, on the other hand, the forest covered the debris slopes, where Mongolian oaks (Quercus mongolica) and royal azaleas (Rhododendron schlippenbachii), which typically grow in the highlands, prevailed. This area was considered favorable for the development of vegetation for the highlands because the density of rock blocks was lower than in Deoksan Stony Slope, and the soil was exposed. Moreover, ash trees (Fraxinus rhynchophylla) and Korean maple trees (Acer pseudosieboldianum) that commonly appear in the valley areas were dominant here. It is probably due to the increased moisture content in the soil, which resulted from creating a depressive landform with a concave shape that is easy to collect rainwater as rock blocks in some areas fell and piled up in the lower region. In conclusion, the area, density of the rock blocks, and distribution pattern of rock block slopes would have affected the vegetation development and species composition in the debris slope landform.

• Journal of the Korean Chemical Society
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• v.67 no.2
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• pp.81-88
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• 2023

The contribution of hydrophobic residues to the protein folding reaction was studied by using HubWA variant proteins with I and L to V mutation. Folding kinetics of all V variant proteins was observed to be satisfied by a three-state on-pathway mechanism, U ⇌ I ⇌ N, where U, I, and N represent unfolded, intermediate, and native state, respectively. Three-state folding reaction was quantitatively analyzed and the free energy of folding of each elementary reactions and overall folding reaction, ΔG^o_UI, ΔG^o_IN, and ΔG^o_UN, were obtained. From the ratio of free energy difference between the variant protein and HubWA, ΔΔG^o_UI/ΔΔG^o_UN (ΔΔG^o_UI = ΔG^o_UI (variant protein) - ΔG^o_UI (HubWA) and ΔΔG^o_UN = ΔG^o_UN (variant protein) - ΔG^o_UN(HubWA)), the contribution of hydrophobic residues to HubWA folding was analyzed. The residues which are located in the hydrophobic core between α-helix and β-sheet, I3, I13, L15, I30, L43, I61 and L67, showed ΔΔG^o_UI/ΔΔG^o_UN value of ~0.5 when each of these residues was mutated to V, indicating that these residues form relatively solid hydrophobic core in the intermediate state. Residues located at the end of secondary structures and loop, I23, L69 and I36 showed ΔΔG^o_UI/ΔΔG^o_UN value below 0.4 when each of these residues was mutated to V, indicating that the region containing these residues are loosely formed in the intermediate state. V17A, L50V and L56V showed fairly high ΔΔG^o_UI/ΔΔG^o_UN value of ~0.8. Since L50 and L56 are located in the region containing long loop (residue 46 to 62), it is suggested that the high ΔΔG^o_UI/ΔΔG^o_UN value of these residues prevents the formation of aggregate at the early stage of folding reaction.