Hydride analysis is required to assess the mechanical integrity of spent nuclear fuel cladding. Image segmentation, which is a hydride analysis method, is a technique that can analyze the orientation and distribution of hydrides in cladding images of spent nuclear fuels. However, the segmentation results varied according to the image preprocessing. Inaccurate segmentation results can make hydride difficult to analyze. This study aims to analyze the segmentation performance of the Otsu algorithm according to the morphological operations of cladding images. Morphological operations were applied to four different cladding images, and segmentation performance was quantitatively compared using a histogram, betweenclass variance, and radial hydride fraction. As a result, this study found that morphological operations can induce errors in cladding images and that appropriate combinations of morphological operations can maximize segmentation performance. This study emphasizes the importance of image preprocessing methods, suggesting that they can enhance the accuracy of hydride analysis. These findings are expected to contribute to the advancements in integrity assessment of spent nuclear fuel cladding.
Background: This study focused on reproductive traits in Hanwoo cattle, specifically the environmental factors affecting gestation length and birth weight. Methods: The records of 1,540 cows calved at the Hanwoo Research Institute from 2015 to 2023 were examined. This study analyzed two populations, linebreeding Hanwoo (LBH) and general Hanwoo (GH), with all cows undergoing estrus synchronization and artificial insemination. The R software was used to compare the differences between the two populations and analyze the environmental factors affecting each trait. Results: The results showed that the average gestation length for LBH was 283.28 ± 5.93 days, which was significantly shorter than that of the GH, which had an average of 285.63 ± 6.21 days (p < 0.001). The average birth weight of LBH calves was 25.10 ± 3.69 kg, significantly lighter than GH calves, which weighed 27.26 ± 4.11 kg on average (p < 0.001). Analysis of environmental factors revealed significant differences in the gestation length of LBH based on dam parity, year, and season of calving. However, no significant differences were observed based on calf sex. For LBH, birth weight showed significant differences based on dam parity, year of calving, and sex of the calf, but not the season of calving. In GH, gestation length varied with dam parity and calving season, but not with calving year or calf sex. The GH birth weight showed differences based on dam parity, year of calving, and calf sex, but not the season of calving. Conclusions: Reproductive traits in the Hanwoo cattle industry are economically vital but are heavily influenced by environmental factors due to their low heritability. An accurate evaluation of the genetic potential of these traits requires an analysis of the environmental factors affecting them. The results of this study serve as foundational data for predicting the potential for genetic improvement in the gestation length and birth weight of Hanwoo cattle.
The blackish cicada, Cryptotympana atrata Fabricius, 1775 (Hemiptera: Cicadidae) was originally distributed mainly in the southernmost remote island, Jeju and rarely throughout low lands in South Korea, but has been explosively increased at the urban areas, where annual temperature is higher. In this study, we sequenced a partial mitochondrial COI from a total of 171 individuals collected throughout 12 localities in South Korea. The haplotype found with the highest frequency in Jeju island shares only with two inland localities in southern region with a low frequency, whereas the haplotype found with the highest frequency throughout inland localities was not found in Jeju island. These results showed that Jeju population, southern region, and other inland populations form somewhat different genetic groups.
The large copper butterfly Lycaena dispar (Haworth, 1803; Lepidoptera: Lycaenidae) has been categorized as a near-threatened species (NT) in South Korea from 2012 mainly due to limited distribution. In this study, we visited 36 sites spread across all South Korean provinces to verify the distributional range of the species and sequenced mitochondrial COI for 53 individuals from nine sites. We observed L. dispar at 15 sites in six provinces, including the two previously known provinces, indicating a southward range expansion. The in-field monitoring and genetic data collectively suggested that L. dispar does not have a limited distribution nor is it isolated, indicating that it should be reclassified as less vulnerable. Our study demonstrates that the combination of field and genetic data can provide a more reliable assessment of the stability of a species.
The clearwing moth, Synanthedon bicingulata (Staudinger, 1887), is a pest that infests various species of cherry trees. However, genetic information regarding the genus Synanthedon including S. bicingulata, is limited. In this study, we sequenced a complete mitochondrial genome (mitogenome) of the species. The 16,255 bp of S. bicingulata mitogenome differs from the typical gene arrangement formed in Lepidoptera: trnQ-trnS2-trnM-trnI arrangement between the A+T-rich region and the ND2 junction. Moreover, the genome has untranslated repetitive sequences in the intergenic space between lrRNA and trnV, as well as the CGA start codon in COI and the TTG start codon in ATP8. Similar observations are noted in species belonging to the tribe Synanthedonini within the genus Synanthedon.
Tropilaelaps mercedesae Anderson and Morgan, 2007 (Acari: Laelapidae) is a serious ectoparasite of the brood of several honey bee species. Among the four recognized species of Tropilaelaps, Korean population was renamed as T. mercedesae from T. clareae on the basis of morphological evidences and genetic data. In this study, we report the complete mitochondrial genome (mitogenome) sequence of T. mercedesae. The 15,119-bp long mitogenome has an identical gene arrangement to that of Chinese sample reported previously. Comparison of two geographic samples showed COII, ND5, ND4, ND6, CytB, and ND1 to have higher number of variable sites than COI, which is often used for population-level study, suggesting these genes to have potential usefulness for population genetic study. The mitogenome sequence of T. mercedesae from Korea could be useful for species identification for geographic samples, trace of the origin of local populations, and illustration of evolutionary distinction among Tropilaelaps species either using part of or whole genome.
Vespa binghami (Hymenoptera: Vespidae) is one of the 10 species in the genus Vespa distributed in South Korea and is the only nocturnal wasp. In this study, we sequenced complete mitochondrial genome (mitogenome) of the species using the Sanger method and using Vespa-specific 30 primer sets. The length of V. binghami was 15,957 bp and the total A/T content was 80.6%. The A+T-rich region of V. binghami was 152 bp, and other Vespa species ranged from 39 bp (V. velutina) to 2,230 bp (V. v. auraria). Compared to the majority of insects, the gene arrangement of V. binghami had differences as followings: trnY-trnI-trnM-trnQ, trnN-trnE-trnS1-trnF, and trnS2-trnL1. However, all species in the genus Vespa registered in GenBank to date were composed of the same arrangement. Phylogenetic analysis using 13 PCGs and 2 rRNA genes showed the sister relationship between V. binghami and V. orientalis with the higher nodal supports.
Bombyx mandarina (Lepidoptera: Bombycidae), the presumed ancestor of the domesticated silkworm B. mori, has long been a subject of study to illustrate the geographic relationships in connection with origin of B. mori. We sequenced 100 mitochondrial genomes of B. mandarina collected from South Korea and Japan and these were combined with public data. Phylogenetic and population genetic analyses showed that all individuals collected in South Korea, except one individual from Inje, formed a strong group together with northern China and some individuals of southern China. This group was placed as the sister group to B. mori strains, suggesting that this group could have been served as an immediate progenitor for B. mori. For further robust inference more analysis is underway.
Spodoptera eridania and S. ornithogalli (Lepidoptera: Noctuidae), which are polyphagous pests that damage various crops such as tomatoes and beans are regulated quarantine species that are highly likely to invade South Korea. Therefore, it is crucial to promptly and accurately identify the presence of S. eridania and S. ornithogalli in crop fields to effectively eradicate as a regulated quarantine species. In this study, we developed a loop-mediated isothermal amplification (LAMP) assay, which allows for rapid in-field identification. To develop the LAMP assay, we selected target species-specific genomic regions from the whole-genome sequences of one target and 13 other lepidopteran species. We validated each five and six primer sets that consistently produced positive reactions in S. eridania and S. ornithogalli, respectively. To test the sensitivity of the each locus, LAMP reactions were performed using various reaction times using crude DNA, which was extracted from various types of adult tissues. All sensitivity tests were also successful.
본 연구는 국내 꽃 정기구독 서비스에 대한 소비자의 인식 과 이용 현황 및 선호도를 파악하기 위해 국내 성인 남녀 중 이용자 225명과 비이용자 291명을 대상으로 설문을 진행하 였다. 대부분의 응답자들은 주로 인터넷과 SNS를 통해 꽃 정 기구독 서비스를 접하였고, 꽃 정기구독 서비스 이용자들은 주로 1~2주에 1회(76.9%), 2~4만 원 가격대(60.4%)의 혼합 된 꽃 상품을 구독하고 있었으며, 대부분 이용 기간은 1년 이 내(84.4%)였다. 꽃 정기구독 서비스를 이용하는 곳은 대부분 집(71.6%)으로, 많은 이용자들이 자기 자신(65.8%)을 위해 서비스를 이용하고 있었다. 꽃 정기구독 서비스에 대하여 이 용자와 비이용자 모두 긍정적으로 인식하고 있었으나, 이용자 들은 비이용자들에 비해 꽃 정기구독 서비스의 가격이 합리적 이고, 삶의 질이 향상되었다고 응답해, 서비스 장점에 대하여 이용자가 비이용자에 비해 더욱 긍정적인 것을 알 수 있었다 (p<0.001). 비이용자들은 꽃 정기구독 서비스 단점으로 포장 쓰레기가 많이 나올 것 같고, 신선도가 떨어질 것으로 우려하 였지만, 이와 반대로 이용자들은 그렇지 않다고 응답하였고, 그 외 단점 문항들에 대해서도 서비스 이용 시 크게 불편함을 느끼지 않는 것으로 나타났다. 응답자들은 꽃 정기구독 서비 스 이용 시 선호하는 상품으로 다양한 꽃이 2~4가지 정도 혼 합된 중간 크기(18~20cm×30~40cm, W×H) 상품을 선호 한다고 응답하였고, 꽃 정기구독 서비스 업체를 선정하기 위 해 고려해야 할 요인으로 이용자와 비이용자 모두 신선도, 꽃 구성, 구매 후기를 중요한 요인으로 응답하였다. 꽃 정기구독 서비스 이용 중 추가로 비용을 지불하면서 이용하고 싶은 서 비스에 대하여 응답자들 모두 절화보존제와 프리미엄 디자인 에 대하여 추가 비용을 지불할 의사가 있다고 응답하였다. 꽃 정기구독 서비스 이용자들은 서비스에 대하여 전반적으로 업 체가 제공하는 정보나 상품에 대해 신뢰하고 있었고, 꽃 정기 구독 서비스 비용은 합리적이라며 긍정적으로 평가하였다. 또 한, 본 서비스에 대한 재이용 의사도 높은 것으로 나타났다. 꽃 정기구독 서비스를 통해 본인을 위한 꽃 소비가 점차 늘어 나고 국내 소비자들의 화훼 소비 형태가 다양하게 변화되었음 을 확인하였으며, 이러한 결과를 바탕으로 앞으로 새로운 국 내 화훼산업 시장이 활성화되고, 지속적인 화훼 소비와 국내 화훼 문화의 발전이 이루어질 것으로 기대한다.
In this study, quantitative analysis is attempted on data collected from Chilgapsan Observatory Star Park in Cheongyang-gun, Chungcheongnam-do. The aim of this experimental study in which quantitative analysis of the Astronomical Science Museum in Korea is conducted is to investigate its current situation and secure basic data. As of July 31, 2023, it has had 283,931 cumulative visitors in total. It had the largest number of visitors when it opened (2009 year), after which their number reduced steadily until the pandemic (COVID-19, 2020–2022). Recently, however, the number of visitors has increased. Generally, the number of visitors is highest in August (20.8$\%$) and least in April (4.1$\%$). The visit rate is higher on weekends (Saturday and Sunday) than on weekdays (Monday–Friday), and groups comprise only about 5.3$\%$ of the total number of visitors. Moreover, it can be confirmed that the number of visitors increases sharply during events. Finally, it was confirmed that the visit rate was unaffected by weather conditions. Considering these results, we propose the following strategies: 1) Establish a special program that reflects “the weekend effect.” 2) Prepare a plan to attract group visitors during the weekdays using “the event effect.” 3) Arrange alternative programs (e.g., experiential activities) that can be conducted indoors regardless of weather conditions. We think that our findings will help establish a roadmap for the direction the Astronomical Science Museum should take and aid in preparing a strategic foundation to preemptively respond to unexpected situations (e.g., pandemics).
Throughfall (TF)—as a diffusive hydrological water flux—significantly affects ecohydrological and biogeochemical processes within forest ecosystems. Recent investigations have revealed the impact on TF generation processes within unmanaged coniferous plantations of under-canopy structures, particularly those laden with dead branches, as well as upper-canopy structures. However, spatiotemporal variations in TF in such plantations remain unexplored. We investigated these variations in TF in a 33-year-old unmanaged Japanese cypress (Chamaecyparis obtusa Endl.) plantation, laden with dead branches, with a high stand density (SD) of 2,500 stems ha−1. Over a two-year period (May 2017 to May 2019), we conducted weekly TF measurements using 28 manual-type TF collectors. We compared the present TF ratio and canopy water storage capacity (S) with those of previous investigations conducted on Japanese cypress plantations. Moreover, we assessed key indices contributing to spatiotemporal TF variations (canopy cover: CC and distance to the nearest stem: TFd) and potentially influential dead branch indices (number of dead branches: TFdb and vertical spacing length on a stem: TFs) to elucidate TF spatial patterns. The results showed that the TF ratio was notably lower than that in previous studies (n = 13), with SD (r = –0.92, p < 0.001) and S (r = –0.87, p < 0.001) emerging as key influential factors among other stand-structure parameters. Spatial TF patterns exhibited a decreasing trend as the gross rainfall (GR) increased. Temporal stability was not significantly associated with CC (r = 0.120, p = 0.544), TFd (r = 0.068, p = 0.731), TFdb (r = 0.211, p = 0.281), or TFs (r = 0.206, p = 0.292) for any of the TF collectors. These findings underscore the important role of GR in determining the spatial variation of TF. Collectively, our results contribute to an enhanced understanding of TF spatiotemporal heterogeneity in unmanaged Japanese cypress plantations with dead branches.