식품 중 곰팡이 이물에 대한 연구를 위하여 식품 제조 및 유통/보관현장에서의 곰팡이 오염수준 및 주요 곰팡이류를 조사하였다. 측정은 식품유형별 총 9장소 (젓갈류, 식초류, 쌀류, 밀가루류, 냉동만두류, 면류, 과자류, 육가공류, 김치류)와 유통/보관현장 총 8장소(물류 창고)에서 진행하였고, 각 생산라인에서 부유곰팡이, 표면 곰팡이 오염도를 조사하였다. 측정결과, 육가공류 생산현장에서 부유곰팡이 오염도가 가장 높게 측정되었으며, 김치류 생산현장에서의 부유곰팡이 오염도가 가장 낮게 측정되었다. 설비 및 벽면에서의 표면 곰팡이 오염도의 경우, 식품 제조 및 유통/보관 현장에 관계없이 거의 검출되지 않았다. 현장에서 검출된 주요곰팡이를 조사한 결과, Penicillium sp., Aspergillus sp., Cladosporium sp., 종이 우점종 곰팡이로 조사되었다.
Phosphine (PH3) resistance in the stored-products insect pests has been reported throughout the world in various insect species, including Rhyzopertha dominica, Tribolium castaneum, and Cryptolestes ferrugineus, leading farmers and fumigators to identify new fumigation tools to control PH3-resistant insect pests in storage facilities. Understanding PH3-resistance mechanisms in insects might contribute to providing clues for the development of new chemicals, including fumigants, to control various PH3-resistant insects. A proteomic study has shown 15 decreased proteins in the PH3-resistant R. dominica (CRD343 strain) in comparison to the PH3-susceptible R. dominica, and among those 15 proteins, dihydrolipoamide dehydrogenase (DLD), a protein involved in the Krebs cycle, was identified (Park et al., 2008). The DLD polymorphisms responsible for genetic resistance have disulfide active sites for PH3 binding and are highly sensitive to arsenic exposure after mutagenesis in insects (R. dominica and T. castaneum) and Caenorhabditis elegans (Schlipalius et al., 2012). Here, two PH3- resistant S. oryzae strains were used to understand the development of PH3 resistance in these insects. Acute toxicity test by PH3 on the two PH3-resistant strains was undertaken followed by ethyl formate inhibition study on cytochrome c oxidase activity. The Lineweaver-Burk plots after inhibition studies showed there were significantly difference in inhibition mode between the resistant strains and the control. The RT-qPCR analysis and the next-generation sequencing of the mitochondrial DNA revealed significant changes in metabolism and energy production. Taken together, the PH3 resistance in S. oryzae was definitely acquired by the overall transformation of biochemical reactions to overcome PH3 toxicity.
Pine wood nematode (PWN), Bursaphelenchus xylophilus causes devastating damage to pines worldwide. To develop new agent for controlling PWN, 43 alkyloxyalcohols were synthesized and nematicidal activity was tested against PWN. As a control, monochamol, which reported to have nematicidal activity was also tested. The nematicidal activity was diffferent according to total carbon chain length in compounds and carbon numbers of diol derivates. The odd numbered carbon diol derivates (ROC5OH, ROC7OH, ROC9OH) showed weak activity. The compounds which had C14H30O2 formula (C11OC3OH, C10OC4OH, C8OC6OH, C6OC8OH) showed the same level nematicital activity as that of monochamol in the term of LC50 value. Thee compounds which had C15H32O2 and C13H28O2 formulas (C12OC3OH, C11OC4OH, C12OC3OH, C10OC3OH, C9OC4OH, C5OC8OH) were followed.
Pine tree, a dominant species in the flora of Korea is the most beloved tree in Korea. However, recent outbreak of pine wilt disease caused by the pine wood nematode (PWN) Bursaphelenchus xylophilus threatens the vegetation of Pinus species seriously. Furthermore, Pinus densiflora and P. thunbergii, the predominant species in Korea forest are highly susceptible to PWN. Therefore, there has been an urgent demand for the development of a new nematocidal compounds to control PWN, which spurred the national research for the development of new compounds. To find novel sources for nematocidal agents, we used various plant resources for the development. In addition to the foreign plant extracts themselves, we also used the extracts of endophytes composed of over 300 endophytic fungi and 1,000 endophytic bacteria from plants which was reported to contain nematocidal activity. Several extracts of endophytes and plant extracts contained strong nematocidal activity, and the resources are analyzed to identify the active nematocidal compounds. These integrated approach of finding effective nematocidal compounds from plants could be a novel way to elucidate the sources for brand-new nematocidal agents.
Pine trees are ecologically important in Korea. They are seriously imperiled by Pine wilt disease (PWD), by pine wood nematode (PWN, Bursaphelenchus xylophilus). Here, we isolated and characterized bacterial endophytes (BEs) from pine trees in Korea for biological control of PWN using BE metabolites. Using culture-dependent approach BE isolates were extracted from three tissues (needles, stems, and roots) of four pine species across 18 sampling sites in Korea. Bacterial isolates were characterized into 389 distinct isolates based on 16S rDNA sequencing. Ethyl acetate crude extracts (CEs) of bacterial liquid cultures were prepared using ethyl acetate and screened for nematicidal activity against PWN. BEs (1,622 isolates) were isolated; their taxonomic binning resulted in 215 operational taxonomic units (OTUs). Analysis of species richness and Shannon’s diversity of the three tissues revealed that BEs colonized the needles more than the stem and root tissues. Furthermore, based on nematicidal activity screening of 389 isolates, 44 BEs were identified, with two isolates exhibiting a significant inhibitory activity against PWN. Taken together, these data revealed numerous nematicidal BEs in pine trees, providing new insights that can serve as an effective and promising alternative approach to combat PWD.
사회성 말벌류의 분류학적 연구는 과거 1960-1980년도까지 1차적으로 한국산 말벌을 정리하여 그 개략적인 윤곽이 나타났으며 90년대 이후 전문 분류학자들에 의해 연구되어 현재 남한지역에서 보고된 사회성 말벌류는 총 2아과 5속 30종이다. 그러나 아직도 분류학적 논의가 필요한 종이 남아 있는 상태이며 특히 각 계급별 및 벌집의 특성은 아직 밝혀지지 않은 종들이 많은 상태이다. 최근 들어서는 외래종 말벌의 침입을 통해 전국으로 확산되고 있는 가운데 공중보건적, 경제적, 생태적 피해가 나타남에 따라 이들의 조절 및 관리에 대한 연구가 일부 진행되고 있다. 또한 기후변화 및 도시화에 의해 전국적으로 말벌류가 증가함에 따라 119 소방서의 벌집제거수가 연간 20만건을 나타내고 있으며 각종 벌쏘임 사고가 빈발하여 연간 10여명의 사망사고가 나타나고 있어 이에 대한 국가적 대책이 필요한 실정이다. 또한 최근 말벌을 이용하여 만든 노봉방주의 수요가 급증하는 가운데 이들의 과학적 검증에 대한 요구가 증가하면서 독성, 타액 등의 효능분석 및 유해성 분석도 일부 진행되고 있다. 그 외 말벌의 공격성분석, 먹이 원분석, 사냥행동 특성, 기생, 천적 등의 생태적 연구도 일부 진행 중에 있다. 이처럼 말벌에 대한 사회적 문제가 커지고 있음에도 불구하고 국내의 말벌 전문 학자 부족으로 인해 가시적인 연구 성과가 미진하며 문제 해결에 대해 제대로 대처하지 못하고 있는 상황이다.
Various symptoms of virus diseases are observed on the cultivated and non-cultivated crops in Myanmar. The virus diseases cause a major limiting factor in the tomato and chili production. During 2018, survey on the virus disease and its vectors in tomato and chili fields were conducted in central regions of Myanmar including Naypyidaw, Mandalay, Magway and Sagaing Divisions. The symptoms observed on tomato and chili were chlorosis, puckering of leaf, upward curling of leaves, reduction in leaf size, vein and stunting. Tomato leaf curl (TLC) disease incidence and severity ranged from 10 to 100% and 37 to 86% respectively. Chili leaf curl (CLC) disease incidence and severity was 30 to 100% and 13 to 100% respectively. The highest incidence and severity of TLC and CLC recorded in Lewe townships, Naypyidaw. Insect vectors observed in those areas were whitefly (Bamisia tabaci), jassid (Emposca sp) and mealy bug, and the white fly was common. Whiteflies are very important vectors for virus in tropical and subtropical regions, but not confirmed to this area. Jassids are also vectors for virus. Both nymphs and adults suck the plant sap and introduce toxin to host plants. Therefore, an infestation may be very damaging and show stunted growth and bushy appearance.
4,4’-dichlorodiphenyltrichloroethane (DDT) has been re-recommended by the World Health Organization for malaria mosquito control in Africa. Previous DDT use has resulted in predisposition of resistance, and with continued use resistance will increase further in terms of level and extent. Drosophila melanogaster is a model dipteran that has many available genetic tools, has been widely used for elucidating insecticide resistance mechanisms, and is related to malaria mosquitoes allowing for extrapolation. The 91-R strain of D. melanogaster is highly resistant to DDT (>1500-fold); however, there is no mechanistic scheme that accounts for this level of resistance. Recently, reduced penetration, increased detoxification, and direct excretion have been identified as resistance mechanisms in the 91-R strain. Their interactions, however, remain unclear. Use of Gal4/UAS-RNAi transgenic lines of D. melanogaster allowed for the targeted knockdown of genes putatively involved in DDT resistance and has identified the role of several cuticular proteins (Cyp4g1 and Lcp1), cytochrome P450 monooxygenases (Cyp6g1 and Cyp12d1), and ATP binding cassette transporters (mdr50, mdr65, and mrp1) in increased sensitivity to DDT. These findings have been further validated in 91-R flies using a nanoparticle-enhanced RNAi strategy, directly implication these genes in DDT resistance in 91-R flies.
Forest insect pests monitoring provides essential information for forest management against their outbreaks. Long-term monitoring data for forest insect pests have been collected by National Institute of Forest Science at national level since 1968. Forest insect pests for long-term monitoring include pine needle gall midge, black pine bast scale, fall webworm, pine moth, spotted lanternfly, etc. The monitoring data were analyzed effect of meteorological factors on the outbreaks of sporadic forest insect pests. Our results showed that meteorological factors can influenced on outbreak of forest insects. The species including Lepidoptera has more occurred when fall and winter temperature were relatively high during the period, suggesting that their outbreaks depends on mortality rate during winter diapause. In Diptera, species abundance was positively related with amount of precipitation in spring but negatively related with summer temperature. The species belong to Hymenoptera was also more abundant when spring temperature was relatively warm. These results can provide useful information for predict potential forest insect pests from climate change.
We investigated the effect of different exercise intensities on biomarkers of oxidant-antioxidant balance, inflammation, and muscle damage. Eighteen healthy and untrained male subjects were enrolled.Subjects were randomly and equally assigned to a moderate-intensityexercise(MIE, 65%VO2max) group(n=9) or a high-intensity exercise(HIE, 85%VO2max) group(n=9).Blood samples were collectedimmediately pre-exercise, post-exercise, and 60min post-exercisetoexamine oxidant-antioxidant balance(d-ROMs; BAP), inflammation(CRP; fibrinogen), muscle damage(CK; LDH), and lactate. Serum d-ROMs and BAP levels were significantly increased post-exercise compared with pre-exercise levels in HIE group(p<0.05). Lactate levels were significantly increased post-exercise compared pre-exercise levels in both the MIE and HIE groups(p<0.05). In addition, post-exercise serum d-ROMs and plasma lactate levels were significantly higher in the HIE group than in the MIE group(p<0.05). These results suggest that although relatively high-intensity exercises may increase oxidative stress levels in the body, they do not produce inflammatory response and/or muscle damage.
Acinetospora asiatica and Botrytella reinboldii are reported as two new records from S. Korea based on morphological studies and molecular analyses. A. asiatica is mainly characterized by the presence of sparsely branched uniseriate filaments with diffused meristematic zones, the formation of crampons at right angles, and the formation of plurilocular sporangia on both prostrate and erect filaments. B. reinboldii is characterized by the presence of irregularly alternating branched uniseriate filaments attached by rhizoids, and single or clustered plurilocular sporangia with a single opening. Molecular analyses of rbcL gene revealed that A. asiatica and B. reinboldii are placed within each clade of Acinetospora and Botrytella, respectively.
목적: 부등상시 보정안경의 임상 성능을 평가하고자 하였다.
방법: 30명을 대상(남자 12명, 여자 18명, 평균 23.7세)으로 부등상시 보정안경을 처방하였다. 평소 안경과 부등상시 보정안경을 착용하고 시력, 안경배율, 부등상시도 및 입체시력을 측정하였다. 착용 1주일 후에 주관적 만족도를 평가하였다.
결과: 부등상시 보정안경 착용 후 우위안과 비우위안의 등가구면교정굴절력 차이는 평소 안경보다 증가 하였으나 유의성이 없었다(0.22D, p=0.41). 단안 교정시력의 차이는 유의하게 감소하였고(0.04, p=0.03), 양안 교정시력은 유의하게 향상되었다(0.07, p=0.00). 좌안과 우안의 안경배율 차이는 평소 안경(2.63%)보다 부등상시 보정안경(1.23%) 착용 후 더 낮았다(p=0.00). 부등상시 보정안경 착용 후 입체시는 46초각 정도 증가하였고(p=0.00), 주관적 만족도에 관한 설문에서 평소 안경보다 개선되었다. 렌즈의 가장자리 두께와 외관상 보기 흉함이 주된 개선사항으로 나타났다.
결론: 부등상시 보정안경이 부등시자에게 편안하고 만족스러운 생활을 제공하는 것으로 나타났다. 또한 부등상시 보정안경의 처방 및 조제와 관련된 임상에서 유용하게 적용할 수 있는 방법을 제시한 것으로 생각 된다.
The morphology, anatomy and reproduction (tetra/bisporic and male) of Lithothamnion japonicum Foslie was studied, using holotype material and materials collected from Korea. Lithothamnion japonicum is characterized based on the presence of encrusting, warty to fruticose thallus, branched or unbranched short and cylindrical protuberances, conical shaped spermatangial conceptacles, branched (dendroid) spermatangial systems formed on floor, walls, and roof of conceptacle chamber, cylindrical shaped spermatangial conceptacle canal, 9-10 cell layered spermatangial conceptacle roof, raised tetra/bisporangial conceptacles without rims, flattened tetra/ bisporangial conceptacle pore plate, 16-50 pores on each pore plate, 6-8 rosette cells surrounded by each pore, pore canal lining filaments composed of tetra/bisporangial conceptacle roof, and buried senescent tetra/bisporangial conceptacles completely infilled with relatively large and irregularly arranged calcified sterile cells. In this study, we report a new record of Lithothamnion japonicum from Korean coasts.
In 2017, the freshwater algae were collected from reservoirs, small ponds, soil, and rocks in Korea. Eight taxa of Chlorophyta (Chlorophyceae and Trebouxiophyceae) have been newly reported in Korea. The unrecorded indigenous species were Chlorolobion braunii, Coelastrum pseudomicroporum, Coelastrum reticulatum var. cubanum, Monoraphidium nanum, Tetrachlorella incerta, Ecdysichlamys obliqua, Gloeotila scopulina, and Stichococcus jenerensis.
To find unrecorded diatom species, random materials were collected from the freshwater, brackish water, and coastal waters. Benthic and periphytic diatoms were sampled from twelve localities. Thirteen species belonging to eight genera are newly added to the national flora of diatom. In the intertidal areas, the five species are new to Korea, Anaulus minutus Grunow, Anaulus simonsenii Witkowski & Metzeltin, Eunotogramma laeve Grunow, Eunotogramma productum Grunow, and Nitzschia subcapitellata Hustedt. The following two species are new from brackish waters, Chamaepinnularia krookiformis (Krammer) Lange-Bertalot & Krammer and Cymatoneis ovalis Heiden. The following four species are new from mountain peatlands, Geissleria ignota (Krasske) Lange-Bertlaot & Metzeltin, Chamaepinnularia hassiaca (Krasske) Cantonati & Lange-Bertalot, Chamaepinnularia mediocris (Krasske) Lange-Bertalot and Pinnularia linearidivergens Kulikovskiy, Lange-Bertalot & Metzeltin. The following two species are new from river or streams, Cymbella hustedtii var. compacta Krammer and Cymbella stigmaphora Østrup.
The aim of this study was performed to evaluate the effects of ice-binding protein from the arctic yeast Leucosporidium (LeIBP) supplementation on cryopreservation of boar sperm. The collected semen was diluted (1.5×108/ml) in lactose egg yolk (LEY) and cooled at 5°C for 3 h. The cooled semen was then diluted (1×108/ml) in LeIBP containing LEY with 9% glycerol and maintained at 5°C for 30 min. The semen was divided into six experimental groups (control, 0.001, 0.005, 0.01, 0.05 and 0.1 mg/ml of LeIBP). The straws were kept on above the liquid nitrogen (LN2) vapors for 20 minutes and then plunged into LN2. After thawing, computer-assisted sperm analysis was used for sperm motility and flow cytometry was performed to assess the viability, acrosome integrity (FITC-PSA/PI), ROS (DCF/PI), lipid peroxidation (BODIPY C11/PI) and apoptosis (Annexin V/PI), respectively. No significant responses were observed for sperm motility. However, sperm viability was significantly increased on 0.05 and 0.1 mg/ml of LeIBP groups compared to control (P < 0.05). In addition, acrosome integrity was significantly increases LeIBP groups (P < 0.05) and both ROS and lipid peroxidation level were lower in all LeIBP groups than those of control (P < 0.05). On the other hand, a significant higher apoptosis rate was observed in 0.05 and 0.1 mg/ml of LeIBP groups compared to control (P < 0.05). It can be assumed that a supplementation of LeIBP in boar sperm freezing extender is an effective method to increase the sperm qualities after cryopreservation.
The present study was conducted to evaluate the effects of high levels of nutrients on the growth performance, blood metabolites and carcass characteristics of Hanwoo cattle. Eighteen Hanwoo steers were fed two types of diets: 1) Nine animals were fed the conventional diet including typical levels of crude protein (CP) and total digestive nutrients (TDN), and 2) Nine animals were fed the treatment diet including high levels of CP and TDN. The average body weight (BW) and dry matter intake (DMI) were greater (P < 0.05) in the treatment group than in the conventional group at early and late fattening stages. Also, in the treatment group, the average daily gain (ADG) was greater (P < 0.05) at the late fattening stage. The serum total lipid and cholesterol levels were higher (P < 0.05) in the late fattening stage of treatment group. The carcass weight, total fat weight, longissimus muscle area and the grade of meat quality were also greater (P < 0.05) in the treatment group than the conventional diet group. This study demonstrates that high levels of CP and TDN exhibit a positive effect on the growth performance and carcass characteristics, indicating that high levels of CP and TDN can be used as a cost-effective feeding program for Hanwoo cattle by shortening the feeding period.
The identification of biomarkers of a living tissues is essentially required to understand specific functions of the cells. In previous study, we reported IGFBP 3 as one of the putative biomarkers, by showing specific expression at porcine spermatogonial stem cells (SSCs) of early stage of porcine testis. In this study, we analyzed the expression of seven members of IGFBP family (IGFBPs) in SSCs and histological expression pattern of pregnancy-associated plasma protein-A (PAPP-A), which plays a role on the growth promoting enzyme by cleavage of IGFBPs in testis of 5 days old pig. RT-PCR analysis showed that IGFBP 1, 2, 3, 4, and 6 were expressed at high level specifically in porcine SSCs compared with whole testis. We performed immunohisotochemical staining of testis sections with PAPP-A and protein gene product 9.5 (PGP9.5) which are the known biomarkers for SSCs. We were not able to find co-expression of PAPP-A and PGP9.5; PAPP-A was expressed only in Sertoli cells and PGP9.5 expression was confirmed in spermatogonium. Additionally, we were able to confirm the GATA4 expression in Sertoli and Leydig cells as a regulator of Sertoli cell function was not detected PGP9.5 expressing cells, indicating indirect evidence of that cytolocalization of PAPP-A expression is limited in Sertoli cells. These results suggested that the PAPP-A expressed in Sertoli cells may play role on regulation of development and differentiation of testicular cells through the IGF axis in neonatal porcine testis.
Net neutrality, which has not been a problem, has recently become a problem for ISPs (Internet Service Providers), and their complaints have been paid by domestic platform companies, but overseas global IT companies such as Google and YouTube, generate huge revenues from domestic markets. In this situation, domestic IT companies claim that it is natural to impose more expensive charges or restrict speed on users who generate huge traffic. On the other side, however, the telecommunication network has become an essential public good that is essential to our everyday life, and because it has been given a monopoly position by a private company to efficiently respond to the explosive demand for telecommunication services, It is necessary to provide equal and universal service and fulfill public duty. In this paper, we deal with the network neutrality problem, focusing on the price elasticity between the CP (Contents Provider) and the ISP, rather than the user who is one side of the two-sided market for the already saturated satellites communication market. We present a game model that determines the optimal price for each platform by Nash equilibrium and analyze how the net neutrality affects CP according to the change of exogenous variables through the proposed game model.
농가 선호도가 높은 분홍색 비모란 선인장 ‘Yeonbit’는 분홍색 품종 ‘Yeonsi’을 모본으로, 분홍색 ‘Yeonsil’ 품종을 부본으로 하여 2011년에 교배하여 육성된 교배종이다. 종자를 70% C2H5OH와 2% NaOCl로 멸균처리한 후, 100mL 삼각플라스크 0.1% 활성탄이 첨가된 Kyoto 배지에 파종하였다. 발아된 유묘는 기저부를 잘라 기배계대 배양된 어린 삼각주에 접목한 후 동일한 배지가 첨가된 시험관에 치상하였다. 6개월 재배 후 온실로 옮겨서 순화과정을 거쳤으며, 기외에서 매년 접목을 하였으며 총 4번을 접목하여 2013년부터 2015년까지 총 3회에 걸쳐 생육특성을 조사하였다. ‘Yeonbit’ 품종은 편원형 모양과 분홍색 구색을 가지고 있다. 그리고 7~9개, 평균 8.0개의 능(rip), 갈색의 직립형 짧은 가시, 그리고 혹(tubercle)이 돌출된 형태로, 모구가 구성되어 있다. 정식 10개월 후 ‘Yeonbit’ 품종의 구직경은 34.5mm였으며 자구는 모구와 같은 분홍색으로 평균 15.4개가 생성되었다. 2015년 육성계통 평가회에서 ‘Yeonbit’ 품종은 기호도 점수 3.7을 받았다. 2017년 6월 12일에 이 품종은 국립종자원에 등록되었으며 종자산업법에 의해 품종보호(등록번호 6752)를 받게 되었다.