This study aimed to evaluate the effects of different feeding levels of domesticated barnyard millet and imported Bermuda hay on the growth performance and structural development of female and male growing goats. A 4×4 Latin square design was used, involving 8 goats with an average age of 3 months: 4 females and males with an initial body weight (BW) of 10.6 kg and 16.0 kg, respectively. Goats were randomly assigned to 4 dietary treatments: T1 (1.5% BW barnyard millet), T2 (1.5% BW Bermuda hay), T3 (2.0% BW barnyard millet), and T4 (2.0% BW Bermuda hay) over a 22-week period. Results indicated that the highest final body weight (FBW) was significantly observed at the highest feeding level (T4), with females reaching 14.9 kg and males 20.9 kg, while the highest average daily gain (ADG) values were recorded for females in T3 at 75.7 g/d and males in T4 at 81.0 g/d (p<0.05). Dry matter intake (DMI) was highest in the T4 group for both females (437.4 g/d) and males (635.9 g/d), with significant differences observed across treatments (p<0.05), whereas the feed conversion ratio (FCR) showed an improving trend, particularly with a value of 6.0 for females in T4. For structural development, the highest feeding levels led to significant increases in body length, body depth, chest width, and chest girth of both sex. Female and male in T4 achieved body lengths of 53.5 cm and 61.8 cm, and body depths of 45.2 cm and 54.8 cm, respectively. Chest width and girth reached 15.9 cm and 66.5 cm in males, and 13.5 cm and 56.5 cm in females. In conclusion, higher feeding levels, especially with Bermuda hay, may positively influence the growth performance and structural development of goats.
자생 바위솔인 와송(Orostachys japonica), 영동바위솔(O. japonica from ‘Youngdong’), 포천바위솔(O. latiellipticus) 의 휴면과 추대에 미치는 일장의 영향을 알아보기 위해 식물생 장상의 일장을 달리하여 실험을 수행하였다. 세 종류의 바위솔 들을 일장이 다른 식물생장상(86.7±8.7μmol·m-2·s-1 PPFD, 24±2℃)으로 옮기자 세 종류 모두 대부분의 일장에서 휴면이 시작되었다. 그러나 이 휴면은 얼마 지나지 않아 타파되기 시작 하였는데, 와송과 영동바위솔은 일장이 길수록 빨리 타파되었 고, 휴면타파에 걸리는 기간도 짧아졌다. 그러나 포천바위솔은 12시간 이하의 단일 조건에서는 휴면 타파가 보이지 않았다. 와송의 경우 16시간 일장에서는 휴면 없이 화서가 신장하는 것을 관찰할 수 있었다. 영동바위솔은 16시간 일장에서 잠시 휴면 에 들어갔으나 곧 타파되었고, 이어서 추대가 이루어졌으나, 포 천바위솔은 어떤 일장에서도 추대가 보이지 않았다. 결론적으 로, 이 연구의 바위솔에서 관찰된 휴면은 자연 조건에서 보이는 휴면과는 성질이 다르며 식물생장상의 낮은 광도 때문에 발생한 것으로 판단되었다. 이로써 바위솔은 환경 변화에 대해 매우 민감하게 반응하는 식물이며, 일장과 광도에 대한 반응은 바위 솔 종류에 따라 다르다는 것을 알 수 있었다.
기후변화로 인해 국내에서의 기온, 강수량, 호우일수가 증가 할 것으로 예측됨에 따라, 토양 답압과 높은 불투수면적 비율이 나타나는 도심지를 중심으로 정원과 공공녹지에 활용되는 식물 소재에 있어 내침수성이 중요한 특성으로 부각될 가능성이 높 다. 그러나 내침수성 식물소재에 대한 대다수의 문헌은 재배경 험이나 각 종의 서식지 환경에 기반하고 있는 경우가 많아 실험 적 검증이 필요하다. 따라서 본 연구는 토양수분함량이 높은 서식지에서 기원한 골등골나물(Eupatorium lindleyanum DC.), 새등골나물(E. fortunei Turcz.), 좀개미취(Aster maackii Regel) 3개 종과 중간인 서식지에서 기원한 까실쑥부쟁이 (A. ageratoides Turcz.) 1개 종의 침수조건에 대한 생육반응 비교로 서식지 환경이 내침수성 평가의 유효한 지표인지 알아보 고자 하였다. 실험대상 종을 6주간 무처리(대조구), 5일 침수처리, 7일 침수처리한 결과, 골등골나물과 새등골나물은 대조구와 처리구간 생육반응에서 유의한 차이가 관찰되지 않아 높은 수준 의 내침수성을 지니는 것으로 나타났다. 좀개미취는 생장반응이 처리구에서 대조구 대비 유의하게 감소하여 내침수성은 제한적 인 것으로 보였으나, 5일 침수처리구에서 광계 II의 최대양자효 율(Fv/Fm)이, 두 처리구 모두에서 지상부 대비 지하부의 비율 (R/S율)이 대조구와 유의한 차이를 보이지 않아 침수조건의 해 소 후 회복 가능성을 지니는 것으로 나타났다. 까실쑥부쟁이는 처리 4 주차에 모든 처리구에서 100%의 고사율을 보여 내침수 성을 갖추지 못한 것으로 판단되었다. 결론적으로, 서식지 환경 은 내침수성과 관련이 있다 할 수 있었으나, 내침수성의 정확한 평가를 위해서는 토양수분함량 외 다양한 환경요소들을 함께 고려해야할 필요성이 있을 것으로 보인다.
큰연영초는 백합과의 다년생 식물이며, 정원용으로 큰 관상적 잠재력을 가지고 있다. 그러나 한반도에서는 희귀식물(EN 범주) 로 알려져 있다. 자연 환경에서 종자 휴면 타파의 phenology를 조사하였다. 큰연영초는 초기 종자길이의 10% 미만인 미성숙배 를 가지고 있었다. 미성숙배는 2013년 7월 하순부터 2014년 6월 하순까지 거의 자라지 않았다. 그러나 2014년 7월 초순부 터 8월 중순까지 빠르게 신장하였다. 종자는 8월 1일부터 발아 하기 시작했고, 대부분의 종자는 2014년 8월 하순에 발아했다. 따라서 종자가 탈리 된 후 발아하는 데 약 1년이 걸렸다. 뿌리는 두 번째 가을 동안에 발달했고, 두 번째 겨울철 저온기간이 지난 후, 2015년 봄에 유묘가 출현하였다. 따라서 자연 환경에서 휴 면이 깨지고 유묘가 출현하는 데 약 2년이 걸렸다. 기내의 배양 온도, 저온 처리 및 GA3 처리 실험에서, 종자는 8주 동안 전혀 발아하지 않았다. 따라서 큰연영초의 종자는 유묘을 생산하기 위해 ‘저온(첫 번째 생리적 휴면을 타파) → 고온(미성숙배의 신 장 및 발아) → 저온(배축휴면을 타파)’의 순차적인 온도의 변화가 필요했다. 결과적으로 큰연영초 종자는 deep simple double morphophysiological dormancy (MPD)를 가지고 있다는 결론을 내릴 수 있다.
This study aimed to investigate the effects of various washing pre-treatments of native Codium fragile as a feed additive on in vitro ruminal fermentation and CH4 production in ruminants. Seaweed was included at 0.5% dry matter (DM) based on the experimental feed (forage : concentrate = 3:7). Treatment groups were classified as follows: experimental feed (C), no washing (T1), washing at 0°C (T2), washing at 22°C (T3) and washing at 70°C (T4) each immersed for 6 minutes in distilled water. The pH consistently fell within the ruminal stability range. In vitro dry matter digestibility was significantly highest in T2, T3, T4 and C, T4 was the lowest at 48 h (p<0.05). NH3-N concentration was significantly highest in T4 at 48 h (p<0.05). Total gas production at 48 h was 19% lower in T4 compared to C (p<0.01). CH4 production (mL/g DM) at 48 h was lower in all treatment groups compared to C, with T3 showing a 31% reduction (p<0.01). Similarly, CH4 production (mL/g dry matter degradability, DMD) at 48 h was 39% lower for T3 compared to C (p<0.01). At 24 h, total VFA was significantly highest in T1 and T4 (p<0.05). The proportions of acetate was significantly highest in C and T3 was the lowest at 48 h (p<0.01). The proportions of propionate was significantly highest in T3 and C was the lowest at 48 h (p<0.01). The acetate to propionate ratio was singnificantly highest in C at 48 h (p<0.01). The proportions of butyrate at 24 h was lower for T3 compared to C (p<0.05). Therefore, this study confirms that Codium fragile can reduce CH4 production when used as a feed additive for ruminants and this effect is not significantly influenced by the washing pre-treatment. However, if washing process is necessary, washing at 22°C is the most appropriate method to remove foreign objects.
This study investigates the effect of team-teaching between Korean English teachers and native speakers of English on English learning anxiety. A total of 248 elementary students in grade 6 participated in this study. One group of students were taught by Korean English teachers and native speakers of English while the other group never had the opportunity to speak with a native speaker in class. A survey questionnaire based on FLCAS (Foreign Language Classroom Anxiety Scale) was newly developed to investigate how the two groups showed differences in English learning anxiety in class. The exploratory factor analysis was undertaken to suggest a three-factor solution. The two groups showed differences in English classroom anxiety and confidence in communication with native English speakers. On the other hand, fear of negative evaluation did not show any significant differences between the two groups. The students who experienced team-teaching showed more confidence in communication with native speakers only at a rudimentary level. Therefore, native English-speaking teachers should make their efforts to develop the skills to promote students’ confidence and higher level of communicative abilities.
본 연구는 관상적 가치가 뛰어난 한반도 자생식물 너도개미 자리[Minuartia laricina (L.) Mattf.]의 산업화를 위한 대량 번 식 기술을 개발하기 위해 수행되었다. 종자 번식 실험에서는 2023년 8월 16일 형태적으로 완전히 성숙한 종자를 채종하여 사용하였으며, 종자의 내부 형태를 관찰한 결과 배가 완전히 발달하여 미숙배로 인한 형태적 휴면(MD)은 없음을 확인하였 다. 또한, 종자를 증류수에 침지시켜 수분 흡수율을 조사한 결과 수분흡수 24시간 후 약 66%의 수분 흡수율을 보여 불투수성 종피에 의한 물리적 휴면(PY)도 없음을 확인하였다. 실온 (22±2℃)에서 후숙처리(Dry after-ripening)를 0, 4, 21주 실 시 후 각각 4, 10, 15, 20, 25, 30℃로 설정된 기내 발아 실험을 진행하였다. 실험의 결과, 후숙 4주 처리 후 20℃에 치상한 종자 의 발아율이 약 76%로 가장 높았다. 후숙 처리를 하지 않은 종자는 12주 내 어떠한 온도 조건에서도 발아하지 않아 생리 적 휴면(PD)으로 판단되었다. 삽목 번식 실험에서는 줄기삽목 (Stem-cutting) 방식으로 진행하였고, 루톤 분제 처리가 발근 에 미치는 영향을 조사하였다. 루톤 분제를 처리하지 않은 처리 구는 발근율과 생존율이 100%로 나타났으며, 루톤 분제가 처리 된 삽수는 이들보다 발근율과 생존율이 통계적으로 유의하게 낮았다. 따라서 너도개미자리 종자는 생리적 휴면 종자로 분류 되며, 4주간의 후숙 처리가 휴면 타파에 효과적인 것으로 확인 되었다. 또한, 너도개미자리 삽목 번식 시 별도의 발근 촉진제 처리가 필요하지 않음을 확인하였다.
장미과의 과일 및 관상용 식물은 세계적으로 경제적, 원예적 가치가 뛰어나다. 장미과의 뱀딸기는 관상 및 약용 작물로써 이용가치가 매우 높은데, 증식방법이 마련되어 있지 않은 실정 이다. 뱀딸기의 종자 종자발아 특성을 조사하기 위해 내부형태 관찰, 수분흡수실험, 온도 별 배양, move-along test, GA3처리 실험을 수행하였다. 뱀딸기 종자는 탈리시점부터 성숙한 배를 지닌다. 수분흡수실험 결과, 침지 3시간만에 종자 무게가 초 기무게 대비 100% 이상 증가하였다. 온도 별 배양 실험 결 과, 25/15, 20/10, 15/6, 5, 25, 20, 15°C에서 각각 8주간 배양하였을 때 88, 71, 61, 12, 89, 39, 17%로 나타났다. Move-along test의 T125/15°C(12주)→20/10°C(4주)→ 15/6°C(4주)→5°C(12주)]에서 12주차까지 72%가 발아하였고 T2[4°C(12주)→15/6°C(4주)→20/10°C(4주)→25/15°C(12주)] 에선 20/10°C까지 발아하지 않았고 25/15°C에 도달하고 나서 발아하여 최종발아율은 16%로 나타났다. GA3처리구에선 배양 3주차에 발아를 시작한 반면에 대조구에선 배양 4주차부터 발 아하였다. 따라서 한반도 자생 뱀딸기 종자는 PD로 분류하였다. 뱀딸기속과 Potentilla속 식물은 서로 근연관계이고, 종간의 종 자휴면에 차이가 나타나 종자휴면 특성에 분화가 일어난 것으로 판단된다.
This study examines the challenges faced by native English-speaking professors who teach general English courses in Korean universities, specifically focusing on the issue of social marginalization. Data were collected through online surveys and interviews. The findings indicate that these professors view themselves as a non-mainstream group within university faculties, often experiencing exclusion from decision-making processes and professional development opportunities, primarily due to language barriers. Moreover, cultural differences and structural discrimination exacerbate these challenges. Although the respondents did not report significant difficulties related to student education and exhibited a strong sense of efficacy in teaching English, some lacked sufficient understanding of the institutional curriculum. To address these issues, this study suggests that, for foreign professors to fully demonstrate their expertise in English education and foster a sense of belonging within the university community, they should be granted the authority and responsibility to participate in curriculum improvement research, along with administrative assistance.
Polyploidization, or genome doubling, has a significant impact on plant speciation and adaptation, and it is commonly used in agriculture to improve crop traits. In this study, we investigated the induction of polyploidy in three wild Allium species native to Korea: A. senescens and A. spirale Willd. and A. taquetii, using colchicine treatments tailored to meet specific experimental requirements. By avoiding tissue culture methods, we developed a more accessible, cost-effective, and scalable approach to polyploidization. Our research demonstrated that polyploid Allium plants exhibit distinct phenotypic changes, such as reduced growth rates and increased stomatal size. Flow cytometry and chromosome counting confirmed the successful induction of polyploidy, with clear peaks indicating double DNA content and stable chromosome numbers in polyploid plants. The presence of B chromosomes in A. spirale Willd. following polyploidization suggest interesting genetic dynamics. Despite the initial growth lags, polyploid plants may offer enhanced photosynthetic efficiency and resilience under optimal conditions. This study highlights the potential of polyploidization to improve ornamental traits in Allium species, thereby contributing to the diversification and sustainability of ornamental plant offerings. Future research should focus on the long-term performance and ecological adaptability of polyploid Allium species to fully harness their horticultural potential.
본 연구는 식물 형태 및 성장 지표를 기반으로 친황다오 해안지역의 10가지 향토식물의 내염성을 평가 하여 내염성 식물의 육종 및 정원 적용에 대한 참고 자료를 제공하기 위해 시도되었다. 10종의 토종식물 묘목을 0.0%, 0.2%, 0.4%, 0.6%, 0.8%, 1.0% NaCl 용액으로 물 배양기에 스트레스를 가하여 식물의 높은 성장 스트레스 지수, 염해지수, 염해율, 생존율을 계산하여 내염성 평가를 진행하였다. 그 결과 염분 스 트레스는 친황다오 해안지역에서 10종의 토종 식물의 성장을 다양한 정도로 억제했으며, 염분 농도가 증가함에 따라 식물의 높은 성장 스트레스 지수, 염분 손상 지수 및 염분 손상 비율은 증가하는 경향을 보였고 생존율은 전반적으로 감소하는 경향을 보였다. 식물에 따라 염분 스트레스에 대한 반응 정도가 다르며, 클러스터 분석과 소속 함수 분석을 통해 친황다오 해안지역의 10가지 향토식물은 극내염성인 뜰보리수(Elaeagnus multiflora), 고내염성 족제비싸리(Amorpha fruticosa), 용버들(Salix matsudana), 광대 싸리(Flueggea suffruticosa), 중내염성 호비수리(Lespedeza davurica), 아까시나무(Robinia pseudoacacia) 그리고 민감식물인 장구밥나무(Grewia biloba var. parviflora), 모감주나무(Koelreuteria paniculata.), 좀목 형(Vitex negundo var. heterophylla) 그리고 싸리(Lespedeza bicolor) 등 4개 유형의 내염성 식물군으로 나눌 수 있다. 이중 종합평가는 1위를 차지한 뜰보리수는 염습지 등 해안지역의 조경재료로 매우 탁월한 것으 로 밝혀졌다.
This qualitative study explores how foreign non-native English speaking teachers (FNNESTs) perceive themselves as English educators and how they exert agency to be better perceived as professionals. Given the close relationship between teacher identity and its implications for educational outcomes, this study is based on Norton’s (2008) perspective on identity, which posits identity as dynamic, contradictory, and constantly changing across time and place. The data collection process included four semistructured interviews with two FNNESTs and four interactions on social networking sites. According to the results, the identities of FNNESTs were shaped through their initial language learning experiences, exposure to critically oriented scholarship in graduate school, their future anticipations, and mostly through their agency in the immediate professional context in which they currently teach. That is, four unique identities and one common identity were identified among the participants. In summary, FFNESTs do not perceive themselves as lacking but rather value their diverse language skills and past experiences as language learners.
The interpretations of null subjects in Korean and Chinese are considered distinct, with Korean allowing both strict and sloppy interpretations, while Chinese only allows strict readings. This study investigated whether such an interpretational difference between Korean and Chinese appeared in Chinese learners’ instantaneous processing of null subjects in Korean and among native speakers of both languages with unlimited time and full cognition. An online experiment and offline surveys were conducted using a priming paradigm with a semantic categorization task, acceptability ratings, and multiple-choice surveys. The results of the online experiment provided partial support for distinct interpretations in Korean and Chinese. Meanwhile, offline acceptability ratings and surveys revealed that Chinese native speakers chose the strict reading in most cases, while Koreans also showed a higher acceptance of the strict reading of non-negated sentences. These findings suggest that the interpretation of null subjects can be influenced by experimental methods, grammatical constraints, and/or influences from discourse, underscoring the need for a more nuanced approach to investigating subject ellipsis in Korean and Chinese.
This study examined the quality characteristics of 10 different lines of native peppers collected from organic farms in Chungbuk province. The study found a strong correlation between the redness (a*) and ASTA values, which both contribute to the perceived quality of peppers. The highest values were observed in the Iyugsa line. The content of capsaicinoid and beta-carotene also showed a positive correlation, with Chilsungcho having the highest statistically significant value. While the total polyphenol content did not correlate with the other indicators, Chilsungcho again had the highest levels. The Yuwolcho line exhibited the highest ABTS radical scavenging ability, while the Eumseongcho line showed the highest DPPH radical scavenging ability. Taking into account the overall bioactivity quality, Chilsungcho had the highest values in terms of total polyphenol, beta-carotene, capsaicinoid, and redness. It also had the second highest total flavonoid content, ABTS, and DPPH radical scavenging activity, all statistically significant. Therefore, Chilsungcho can be considered an excellent choice when considering physiological activity. Furthermore, this study provides valuable information about the unique characteristics of these 10 native pepper lines, which can assist in selecting the appropriate pepper for food manufacturing and serve as a helpful resource for future research.
Islands often have relatively well-preserved ecosystem and an abundance of bioresources with a high conservation value, with unrecorded species continuing to be reported (Hong, 2011). Approximately 1,000,000 species of insect known worldwide (Costello et al., 2012), and 20,710 species are known in Korea (NIBR, 2023). Among these, there are 6,117 species in Korean islands (HNIBR, 2022). Native insect Bio-scan project for Korean islands is to estimate the number of insect species on Korean islands. We attempted to estimate the number of insect species on Korean islands using Barcode Index Number (BIN), and also found unrecorded species. The samples were collected four times from April to July at five locations in the Amtedo, an island located in Shinan-gun Jeollanam-do. We tried to obtain a minimum of one to usually a maximum of four samples per morphospecies to enable DNA barcoding.
Vespa mandarinia (Vespidae: Hymenoptera) is one of the two largest true hornets known to science. The species is a noted predator of social Hymenoptera and a significant pest of managed honey bees in its native range, but is also known to feed on a wide variety of other species when available. Most of the prey records for V. mandarinia are derived from visual observations in Japan, with sparse observations from other parts of its native range. A population of V. mandarinia was detected in North America in 2019 and five nests were removed between 2019 and 2021. We extracted DNA from larval meconia from four nests collected in Washington State, USA, and amplified the CO1 region to determine the potential prey base. We compared these with sequences generated from three nests in the Republic of Korea, and with prey pellets collected from foraging hornets at several locations in Korea. Results indicate that the prey base was much wider in the ROK than the USA, although social Hymenoptera were the most abundant and common prey items in both regions. Prey range seems to be bound by an intersection of organism size and local biodiversity, with little evidence to suggest that the latter is a limiting factor in colony success.
Over four years (2020–2023), 305 traps were strategically placed across South Korea to collect data on Vespidae species. Our findings showed that Vespula flaviceps, Vespa crabro, and Vespula koreensis were the most frequently encountered species. Vespa velutina was also widespread, suggesting its successful integration into local ecosystems. The ARL analysis, using the “apriori” algorithm, identified significant co-occurrence patterns and potential interactions. The rules generated indicated both competitive and coexistent relationships with varying levels of association strength across different regions. Clustering analyses, including hierarchical and k-means clustering, grouped species based on their occurrence similarities. The distinct clusters formed in the analysis highlighted the unique ecological roles and interactions of V. velutina and other Vespidae species in South Korean ecosystems.