• 제목/요약/키워드: Asia- North America

검색결과 170건 처리시간 0.031초

Sexuality of Aruncus aethusifolius (Rosaceae)

  • Yun, Narae;Suh, Hwa-Jung;Oh, Sang-Hun
    • 식물분류학회지
    • /
    • 제47권3호
    • /
    • pp.189-195
    • /
    • 2017
  • Aruncus L. is a small genus which is distributed in the circumpolar regions of the Northern Hemisphere, including Europe, Asia, and North America. In Korea, there are two taxa, A. dioicus var. kamtschaticus and A. aethusifolius. Aruncus aethusifolius is a species endemic to Korea, occurring only on Jeju Island. An important characteristic of Aruncus is dioecy. However, there is some controversy regarding the sexuality of this genus, and little is known about A. aethusifolius. To characterize the sexuality of A. aethusifolius and to provide insight into the evolution of its sexual system, we investigated natural populations and herbarium specimens of A. aethusifolius. The results indicate that the species has carpellate, staminate, and bisexual flowers. Carpellate flowers are always borne on separate individuals, and staminate flowers are borne either on separate individuals or mixed with bisexual flowers on the same individuals. The sexuality of A. aethusifolius is defined as polygamo-dioecious. The polygamo-dioecious type is also found in A. dioicus var. dioicus and A. dioicus var. kamtschaticus and thus may be a general condition in Aruncus.

Gnaphalium tranzschelii Kirp. (Asteraceae): An unrecorded species from Korea

  • Lee, Dong Hyuk;Byeon, Jun Gi;Heo, Tae Im;Park, Byeong Joo;Lee, Jun Woo;Kim, Ji Dong;Choi, Byoung Hee
    • 한국자원식물학회:학술대회논문집
    • /
    • 한국자원식물학회 2019년도 춘계학술대회
    • /
    • pp.78-78
    • /
    • 2019
  • Gnaphalium L. is a small herbaceous genus comprising up to 80 species in worldwide (Asia, North to South America, Africa, and Oceania). This genus is highly polymorphic which embrace uncommon broad morphological boundary, and thus further studies were needed to proper taxonomic delimitations for the genus and its relatives. Gnaphalium uliginosum L. was usually found in moist sites such as margins of lake, pond, reservoir, stream banks and paddy field. This squat plant is solely known species in Korean Gnaphalium. During the revisionary study of the tribe Gnaphalieae (Asteraceae) in Korea, however, we found several materials in domestic herbaria (e.g., SNU, KWNU) that identified as G. uliginosum or Gamochaeta pensylvanica (Willd.) Cabrera collected from central to northern Korea, but clearly differ to the morphology of G. uliginosum. The external morphology of the materials is seemingly the only feature at odds with G. uliginosum. However, its morphological characters such as tall erected stems (ca. 30cm), hairs on seeds and whitish tomentose hairs on the whole plants are easily distinguished from G. uliginosum, and rather it looks like G. tranzschelii Kirp. Although the name G. tranzschelii have been treated as synonym of G. uliginosum by several authors, its distinct morphology might be sufficient to separate to two independent taxa. Generally, the morphological polymorphisms and hybridization of G. uliginosum complicate the taxonomy of the species, and thus further investigation for their habitat, distribution and morphology were needed to their taxonomic entity.

  • PDF

Amphetamine-type Stimulants in Drug Testing

  • Chung, Heesun;Choe, Sanggil
    • Mass Spectrometry Letters
    • /
    • 제10권1호
    • /
    • pp.1-10
    • /
    • 2019
  • Amphetamine-type stimulants (ATS) are a group of ${\beta}$-phenethylamine derivatives that produce central nervous system stimulants effects. The representative ATS are methamphetamine and 3, 4-methylenedioxymethamphetamine (MDMA), and abuse of ATS has become a global problem. Methamphetamine is abused in North America and Asia, while amphetamine and 3, 4-methyle nedioxym ethamphetamine (Ecstasy) are abused in Europe and Australia. Methamphetamine is also the most abused drug in Korea. In addition to the conventional ATS, new psychoactive substances (NPS) including phenethylamines and synthetic cathinones, which have similar effects and chemical structure to ATS, continue to spread to the global market since 2009, and more than 739 NPS have been identified. For the analysis of ATS, two tests that have different theoretical principles have to be conducted, and screening tests by immunoassay and confirmatory tests using GC/MS or LC/MS are the global standard methods. As most ATS have a chiral center, enantiomer separation is an important point in forensic analysis, and it can be conducted using chiral derivatization reagents or chiral columns. In order to respond to the growing drug crime, it is necessary to develop a fast and efficient analytical method.

Unveiling the Diversity of Hydnum in the Republic of Korea with One New Species, Hydnum paucispinum

  • Ji Seon Kim;Wonjun Lee;Changmu Kim;Hanna Park;Chang Sun Kim;Young Woon Lim
    • Mycobiology
    • /
    • 제51권5호
    • /
    • pp.300-312
    • /
    • 2023
  • Hydnum is a genus of ectomycorrhizal fungi belonging to the Hydnaceae family. It is widely distributed across different regions of the world, including North America, Europe, and Asia; however, some of them showed disjunct distributions. In recent years, with the integration of molecular techniques, the taxonomy and classification of Hydnum have undergone several revisions and advancements. However, these changes have not yet been applied in the Republic of Korea. In this study, we conducted an integrated analysis combining the morphological and molecular analyses of 30 specimens collected over a period of approximately 10 years in the Republic of Korea. For molecular analysis, the sequence data of the internal transcribed spacer (ITS) region, the large subunit of nuclear ribosomal RNA gene (nrLSU), and a portion of translation elongation factor 1-a (TEF1) were employed as molecular markers. Through this study, we identified eight species that had previously not been reported to occur in the Republic of Korea, including one new species, Hydnum paucispinum. A taxonomic key and detailed descriptions of the eight Hydnum species are provided in this study.

유엔의 북핵 대북제재조치의 실효성과 북한의 체제생존전략 (Efficacy of UN's Sanctions on North Korea's Nuclear and North Korea's Regime Survival Strategy)

  • 김주삼
    • 한국과 국제사회
    • /
    • 제2권1호
    • /
    • pp.69-92
    • /
    • 2018
  • 북한은 2006년 1차 핵실험을 시작으로 2017년 9월까지 총 6차례의 핵실험을 감행하였다. 북한은 미국의 대북적대시 정책에 대응하기 위한 일환으로 체제수호와 방어적 차원에서 핵무장력 담보 전략을 전개하고 있다. 그러나 북한 핵실험의 전략적 목표가 북미협상을 통해 북한체제 위기를 극복하고 그들의 한반도 사회주의통일을 위한 핵무장력을 완성하는 데 있음은 주지의 사실이다. 북한의 계속된 핵실험은 한반도평화를 위협하는 직접적인 요인이 되고 있으며, 동북아안보 역학구도에 간접적인 요인으로 작용하고 있다. 유엔안보리는 이러한 북한의 무모한 핵실험에 대해 지난 10년 이상 6차례의 유엔안보리 결의로 대북제재조치를 단행해 왔다. 그러나 북한 김정은 정권은 유엔과 미국 등 국제사회의 대북제재 조치에도 불구하고 핵 경제병진노선을 고수하겠다는 입장이다. 유엔과 미국의 대북제재조치가 북한에 대한 효과적인 영향을 주지 못한 것은 북한이 강도높은 핵실험으로 격상시키는데 요인으로 분석된다. 2017년 미국의 트럼프 행정부가 대북제재 조치 수단 가운데 하나인 대북 군사옵션은 한반도에서의 전면전과 국지전 양상으로 예상된다. 미 트럼프 행정부는 이전의 미국 행정부의 대북제재 조치 양상과는 다르게 세컨더리 보이콧이라는 외교압박전술을 시도하고 있다. 그럼에도 불구하고 북한은 유엔과 미국의 대북제재조치에 대해 북 미 간 전면적인 군사대결 입장을 밝히며 '벼랑끝 전술'로 맞서고 있다. 북한은 당분간 체제생존차원에서 핵 경제병진노선을 추진할 것으로 판단된다. 북한체제는 미 중 간의 현실주의적 국가전략 추진으로 체제붕괴 변수가 나타날 수 있다는 점에서 북한의 전략적 선택의 폭은 좁아진다.

신공항(新空港)의 허브공항화(空港化)에 관한 소고(小考) (An Essay on the Possibility of New Seoul International Airport as a Regional Hub)

  • 김종석
    • 항공우주정책ㆍ법학회지
    • /
    • 제5권
    • /
    • pp.303-320
    • /
    • 1993
  • The construction of New Seoul International Airport is under way despite much controversy. Among much discussed, but not well-formulated controversy is the possibility of the airport as a hub in the North Asia Region. This paper specifies the factors which render it possible for an airport to be a regional hub. Then each factor is applied to the new airport to see whether it can function as a hub airport. Also examined is the qualitative cost and benefit calculation related to the hub function. The usual discussion has missed one big point of cost side of hub function in the belief that the hub only produces benefits to the national economy where the airline and airport industry belong; earlier-than-expected congestion and the necessity to expand the airport sufficiently enough to accommodate the increasing air demand. An airport as a hub is determined by several factors; geographical location ; economic status of the country where the airport belongs ; bilateral air service agreements according to which the airlines can exercise the route rights; the airport charges which directly influence the cost structure of the carriers ; international aviation and airport related policies of each country in the region ; airport capacity etc. The tentative implications of this paper are the followings; first, the new airport is able to function as a regional hub in the transpacific routes which connect Asian countries and North America. That is, directional hubbing by the airlines is implicated; second, the main benefits may be accrued to american airlines exercising all the route rights in the Asian region; third, the governmental effort to make the new airport a regional hub must take caution in optimizing the hubbing level (% of transitting passengers and freight) between the benefits and the costs. Further Studies may include optimal level of hubbing for the new airport and, quantification of the impact of the new airport on the national economy depending on the degree of hubbing.

  • PDF

Current status and future trends for pork production in the United States of America and Canada

  • M. Todd See
    • Animal Bioscience
    • /
    • 제37권4_spc호
    • /
    • pp.775-785
    • /
    • 2024
  • Pork production is a significant agricultural enterprise in the United States and Canada. The United States is the third-largest global producer of pork and Canada ranks seventh in pork production. The North American Free Trade Agreement and its successor, the U.S.-Mexico-Canada Agreement, have facilitated trade and integration between the two countries. The majority of production systems are modern and intensive, characterized by large vertically integrated farms using advanced technologies. Both nations benefit from their status as major producers of feed grains, with the United States leading in corn and soybeans, while Canada excels in canola and barley production. The regulatory frameworks for food safety, animal welfare, and environmental stewardship differ slightly, with the FDA and USDA overseeing these aspects in the United States, and Health Canada and the Canada Food Inspection Agency in Canada. The United States and Canada also have well-established distribution networks for pork products, relying on both domestic and international markets. Export markets play a crucial role, with the United States being a major importer of Canadian pigs, and both countries exploring opportunities in Asia. Despite a rise in global demand, domestic pork consumption trends differ, with per capita consumption remaining stable in the USA and declining in Canada. Changing consumer preferences, including a demand for ethically raised and locally sourced pork, may influence production practices. Future trends in pig production include a focus on consumer concerns, sustainability, disease prevention, reduction of antimicrobial use, and advancements in technology. The industry is adapting to challenges such as disease outbreaks and changing regulations, with a strong emphasis on animal welfare. Labor and workforce considerations, along with advancements in technology and automation, are expected to shape the efficiency of pork production in the future.

Microstroma juglandis에 의한 호두나무 흰곰팡이병 발생 (Occurrence of Downy Leaf Spot on Juglans regia Caused by Microstroma juglandis in Korea)

  • 이상현;이승규;박지현;조성은;신현동
    • 식물병연구
    • /
    • 제17권3호
    • /
    • pp.386-390
    • /
    • 2011
  • 2011년 6월에 김천과 무안의 호두나무 재배지에서 잎에 노균병 병징과 유사한 증상이 관찰되었다. 병든 잎의 뒷면에는 다각형의 병반에 흰색의 곰팡이가 눈꽃처럼 형성되었고, 상응하는 잎의 앞면에는 퇴록 부분이 생겼다. 병세가 진전되면서 병든 조직은 붕괴되었고 나중에는 괴사되었다. 이 병의 원인균은 형태적 및 배양적 특징으로 보아 Microstroma juglandis로 동정되었다. 또한 균주의 ITS rDNA 염기서열을 GenBank에 등록된 M. juglandis의 자료와 비교하여 100% 일치함을 확인하였다. 호두나무 묘목에 병원성 검정을 실시하여 코흐의 원칙을 만족시켰다. 이 병은 지금까지 북미, 유럽, 오세아니아 그리고 서아시아(인도, 파키스탄, 터키)에서 보고되었다. 이 연구를 통하여 한국을 포함한 동아시아에서는 이 병을 처음으로 보고하며, 병명은 '호두나무 흰곰팡이병'으로 제안한다.

다문화 장서에 대한 목록 구축의 경험과 교훈 (Lesson from the Cataloging Experience on Multicultural Collection)

  • 노지현
    • 한국도서관정보학회지
    • /
    • 제39권4호
    • /
    • pp.397-420
    • /
    • 2008
  • 이 연구는 최근 다문화도서관이나 도서관에서의 다문화서비스에 대한 관심이 증가함에 따라 현실적인 문제로 다가오고 있는 '다문화 장서의 목록 구축'에 대한 문제를 논의하고자 하는데 목적을 두고 있다. 특히 이 연구에서는 "(사)아시아공동체 부설 국제어린이도서관"에서 소장하고 있는 1만 여권의 다문화 장서에 대한 목록 구축 경험에 기초하여 향후 다문화 장서의 목록 구축에 적용할수 있는 체험적 방안을 도출하고자 하였다. 구체적으로, 이 연구에서는 (1) 그동안 다문화 장서의 목록 구축에 관한 국내외 도서관계의 기존 논의를 추적하고, (2) 현재 우리나라의 공공도서관과 대학도서관, 그리고 민간도서관에서 경험하고 있는 다문화 장서 목록 구축의 사례와 북미 도서관계의 사례를 비교하여 살펴본 다음, (3) 실제 목록 구축의 경험을 통해 향후 우리 도서관계에서 다문화 장서의 목록을 체계적으로 구축하기 위한 방안과 향후 과제에 대해 논의하였다.

  • PDF

A new species of Parastenocaris from Korea, with a redescription of the closely related P. biwae from Japan (Copepoda: Harpacticoida: Parastenocarididae)

  • Karanovic, Tomislav;Lee, Wonchoel
    • Journal of Species Research
    • /
    • 제1권1호
    • /
    • pp.4-34
    • /
    • 2012
  • Parastenocaris koreana sp. nov. is described based on examination of numerous adult specimens of both sexes from several localities in Korea. Scanning electron micrographs are used to examine intra- and interpopulation variability of micro-characters, in addition to light microscopy. The new species is most closely related to the Japanese P. biwae Miura, 1969, which we redescribe based on newly collected material from the Lake Biwa drainage area. The two species differ in size, relative length of the caudal rami, shape of the anal operculum, shape of the genital double somite, relative length of the inner distal process on the female fifth leg, as well as relative length of the apical setae on the second, third, and fourth legs exopods in both sexes. Detailed examinations of three disjunct populations of P. koreana reveal also some geographical variation, especially in the surface ornamentation of somites, which may indicate some population structuring or even cryptic speciation. Lack of intraspecific variability in the number and position of sensilla on somites, as well as their potential phylogenetic significance, is a novel discovery. Both species examined here belong to the brevipes group, which we redefine to include 20 species from India (including Sri Lanka), Australia, East Asia, Northern Europe, and North America. A key to species of this group is also provided. In order to test the monophyly of the redefined brevipes group with highly disjunct distribution, as well as relationship between different species, a cladistics analysis is performed based on 39 morphological characters and with help of three outgroup taxa. Six equally parsimonious cladograms are generated, all of which show that the ingroup is well defined by at least three synapomorphies. Reconstructed phylogeny questions the previously suggested hypothesis about the origin of this group in South East Asia, with one Australian species showing the most basal position. We speculate that the present distribution of this group may be a combination of ancient vicariance and subsequent dispersal, with a possible origin in the Gondwanaland, in the rift valley between Australia and India.