Metagenomic Analysis of Fungal Communities Inhabiting the Fairy Ring Zone of Tricholoma matsutake

( Miae Kim1 ),( Hyeok Jun Yoon ),( Young Hyun You ),( Ye Eun Kim ),( Ju Ri Woo ),( Yeong Gyo Seo ),( Gyeong Min Lee ),( Young Ja Kim ),( Won Sik Kong ),( Jong Guk Kim ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.10

Tricholoma matsutake, an ectomycorrhiza that has mutual relationships with the rootlet of Pinus denisflora, forms a fruiting body that serves as a valuable food in Asia. However, the artificial culture of this fungus has not been successful. Soil fungi, including T. matsutake, coexist with many other microorganisms and plants; therefore, complex microbial communities have an influence on the fruiting body formation of T. matsutake. Here, we report on the structures of fungal communities associated with the fairy ring of T. matsutake through the pyrosequencing method. Soil samples were collected inside the fairy ring zone, in the fairy ring zone, and outside the fairy ring zone. A total of 37,125 sequencing reads were obtained and 728 to 1,962 operational taxonomic units (OTUs) were observed in the sampling zones. The fairy ring zone had the lowest OTUs and the lowest fungal diversity of all sampling zones. The number of OTUs and fungal taxa inside and outside the fairy ring zone was, respectively, about 2 times and 1.5 times higher than the fairy ring. Taxonomic analysis showed that each sampling zone has different fungal communities. In particular, out of 209 genera total, 6 genera in the fairy ring zone, such as Hemimycena, were uniquely present and 31 genera, such as Mycena, Boletopsis, and Repetophragma, were specifically absent. The results of metagenomic analysis based on the pyrosequencing indicate a decrease of fungal communities in the fairy ring zone and changes of fungal communities depending on the fairy ring growth of T. matsutake.

산성강하물이 지표수의 산성화에 미치는 영향 Ⅰ: 현장 조사

김영관,이동석,김만구,우경식 江原大學校 附設 環境硏究所 1997 環境硏究 Vol.14 No.-

Effects of acid deposition on the acidification of surface water over a short period were studied during June~October, 1995. A reservoir located in Chunchon, Kangwondo was selected for this study because this reservoir had received little man-made pollutants. Geological survey within the study area was carried out and the pH of a small and shallow stream flowing from the mountain valley down to the reservoir was monitored. Rainfall was measured by using a rain gauge and the precipitation was collected by automatic precipitation sampler. During the study period, rain pH was in the range of 3.81~5.77 with an average of 4.8. The EC was in the range of 8~189㎲/cm with an average of 10.6㎲/cm. Ionic composition of the rainfall showed that, of the anions, deposition of SO₄^(2-) was highest with 3,119.7 kg/㎢, and is was NH^(4+)with 1,053.2kg/㎢ for cations. The surface water pHs were maintained neutral or weak basic, representing little evidence of acidification regardless of the acidic rainfall pH. Every time of sampling, however, the pHs exhibited increasing tendency as elevation of measuring site of the stream become lowered, which indicated the impacts of acid-base reactions by acidic or basic substances during travel of water downstream. This result suggested the necessity of further research to determine the respective buffering capacity of soil and underlying rocks. 산성강하물이 단기간에 걸쳐 지표수의 산성화에 미치는 영향을 조사하기 위하여 1995년 6월 부터 10월까지 외부오염원이 거의 없는 강원도 춘천시에 위치한 저수지를 선정하여 인구를 수행하였다. 연구지역 일대의 지질을 조사하고 산골짜기에서 저수지로 흐르는 작고 얕은 하천의 수질을 분석하였다. 강우량은 우량계를 이용하여 측정하였고 강하물은 자동포집기를 이용하여 포집하였다. 연구기간동안의 강우의 pH범위는 3.81~5-77로 평균 4.8을 나타내었으며 전기전도도(EC)sms 5~189㎲/cm로 평균 10.6㎲/cm를 나타냈다. 음이온 중에서는 SO₄^(2-)의 강하량이 3,119.7kg/㎢로 가장 많았고, 양이온 중에서는 NH^(4+)가 1,053.2kg/㎢로 가장 많았다. 지표수의 pH는 중성 또는 약염기성으로 강우의 pH가 산성이었음에도 지표수의 산성화 현상은 관찰되지 않았다. 그러나 골짜기에서 흐르는 하천수를 측정할때마다 측정지점의 고도가 낮아질수록 pH값은 증가하는 경향을 나타내어 물이 하류로 흘러가는 동안에 일어난 산성 또는 염기성물질로 인한 산염기반응의 영향을 보여주었다. 이 결과는 토양의 완충능력과 모암내에서의 중화능력을 각각 구별하여 조사할 필요성을 제시하였다.

일제시대의 검도에 대한 의미

김영학,이인희,허건식 龍仁大學校 武道硏究所 1998 武道硏究所誌 Vol.9 No.1

An mentioned above, Korean Kumdo may be considered that Japanese Kendo as a sport has been introduced and popularized here. Some argue that a conservative way of thought due to the principle of Confucianism here interrupted a continuity of Korean Kumdo until the open-door period. But it is high probable that at that time Japanese Kendo has been already introduced and performed here to educate army or police without any difficulty. And it can not dendy that a continuity of Korean traditional Kumdo might be interruped long before the open-door period. A ter the Japanese annexation of Korea. the encouragement of military arts by the political intention of Japan played a remarkable role on the introduction of Japanese Kendo into Korea. and also Kendo was used to maintain public peace and order as a game of national defence, and the common here could not easily contact with Japanese Kendo. That is why then Kendo was started just for the Japanese for the purpose of fostering a Japanese sprit, used as a means to emphasize Japanese Imperial civilians as a colony policy. In the end, it is possible that them many civilians would experience Japanese Imperial civilian gymnastics.

放射電磁波에 의한 絶緣診斷에 관한 硏究

김영훈,박원주,이동인,김충년,이광식 嶺南大學校 工業技術硏究所 1995 工業技術硏究所論文集 Vol.23 No.1

In this paper, the detect of insulation disorder and process degree of insulation degradation of power apparatus, the waveform of discharge current, magnitude of discharge and frequency spectrum of the electromagnetic wave radiated from partial discharge by simulating with needle-to-plane electrode geometry and dielectric with artificial void, were investigated. The results obtained can be summarized as follows. 1) Streamer pulses occur near the positive cycle and trichel pulses near the peak of negative cycle of applied voltage. At that time, discharge magnitude of trichel pulses and streamer pulses was observed about 200[pC] and 500[pC] in air, respectively. 2) The level and frequency spectrum of radiated electromagnetic waves were increased about 20∼40[dB] at under 200[MHz] and about 2∼3[dB] above 200[MHz], compared with background noises. 3) A sudden change of discharge magnitute above 20∼30[pC] was observed with various applied voltages, but the magnitude showered to tend to saturate at 300∼300[pC] in dielectric. 4) The level and frequency spectrum of radiated electromagnetic waves were increased about 3∼6[dB] under 200[MHz]and about 2∼3[dB] above 200 [MHz], compared with background noises.

PDLC의 상 변환 특성

김영식,이영재,조무희 단국대학교 1996 論文集 Vol.30 No.-

Phase separated liquid crystal in PDLC(polymer dispersed liquid crystal) has a characteristic behavior of alignment by the external electric field. There are three kinds of methods for fabrication of PDLCs, PIPS(polymerization induced phase separation), TIPS(thermally induced phase separation),and SIPS(solvent induced phase separation). We have made PDLC samples by using the TIPS method and studied the characteristics of phase separation, We have used 5CB(K15), 8CB(K24), and 10CB(K30) as liquid crystal, and PMMA and PVEM as polymer. Phase separation characteristics according to the rate of temperature cooling were observed by a polarization microscope, and quantitatively measured by light scattering method.

네마틱 액정셀의 배향막 제조 및 특성

김영식,홍선주 단국대학교 1998 論文集 Vol.33 No.-

LC alignment layers were fabricated by spin­coated polyimide films and the characteristics of nematic liquid crystal cells were measured. The 3rd harmonic beam(λ=355 nm) of the Nd:YAG laser was used for photo­alignment method, and the soft velvet was used for rubbing. Orientational order of the LC molecules was measured for various cells with different rubbing strength parameters. For small values of the parameter the orientational order is increasing and the threshold voltage is decreasing to the increased value of the parameter, and both of them are saturated over the limited value. The measured value of orientational order shows that the rubbing method is more efficient than the photo-alignment method.

유전체로 둘러싸인 속빈 직육면체 도파관을 사용한 레이저 공진기에서 횡특성모드의 왕복손실

金允溟,金永植,李鍾旿,徐七成,박재우 단국대학교 1989 論文集 Vol.23 No.-

The round-trip losses of CO_2 laser wavelength in a hollow rectangular dielectric waveguide with external spherical mirrors are calculated. The propagative attenuations of some higher order modes with different polarization are analyzed as well as EH_11 fundamental mode. Computations of the losses in coupling radiation of various modes from the guide into free space and back into the guide, as a function of mirror curvature and position, are also presented. The overall return losses of various modes are the sum of the two kinds of losses.

Multi-Domain 방법을 이용한 TN-LCD의 광시야각 구현

김영식,김일두 단국대학교 1999 論文集 Vol.34 No.-

Multi-domain method has been used for broadening the viewing angle of TN-LCD which is generally showing an unsymmetry in the up and down side and a narrow viewing angle in the up side. We measured the orientational order and the T-V curve to find out the suitable rubbing strength of the multi-domain cell. The characteristics of the cell was estimated by measuring the viewing angle and the gray scale. The four-domain cell has a symmetrical wide viewing angle in every side and the gray inversion is not occurred in any side. The multi-domain cell is found to be useful in application of the gray scale.

산성강하물이 지표수의 산성화에 미치는 영향 Ⅱ: 컬럼연구 및 현장조사

김영관,우경식 江原大學校 附設 環境硏究所 1997 環境硏究 Vol.14 No.-

토양층과 모암층에서의 산성우에 대한 중화능력을 평가하기 위하여 인공강우를 이용한 컬럼실험을 실시하였으며 토양을 이루고 있는 모암 특성의 차이에 의한 산성강하물의 환충효과를 비교하기 위하여 연구지역내의 모암의 조성광물에 차이가 있는 두 개의 골짜기를 선정하고 골짜기에 흐르는 지표수의 pH를 1996년 5월부터 1996년 10월까지 측정하였다. 컬럼실험에서 사용한 인공강우는 증류수에 황산과 질산을 적절히 첨가하여 pH를 각각 3,4, 및 5로 조절하였으며 컬럼유출수의 주요 양이온과 음이온을 측정하였다. A층위와 B층위의 양이온 교환용량(CEC)은 각각 9.68 meq/100g과 6.16 meq/100g 이었으며 인공강우의 살포시 컬럼유출수의 pH는 중간층토양에서보다 양이온 교환용량이 큰 표층토양에서 더 크게 나타났다. 컬럼유출수에서의 Ca^(2+), Mg^(2+), Na^(+)의 합이 점차로 감소하여 지속적인 산성우는 토양의 양이온 교환용량을 감소시키는 것으로 나타났다. 현장조사결과에 따르면 골짜기의 하류로 내려옴에 따라 지표수의 pH는 계속 증가하여 하류로 흐르는 과정에서의 완충효과를 나타내었다. 이러한 완충효과는 모암의 조성광물중 kaolinite와 illite이외에도 smectite를 함유하고 있는 골짜기에서 더 크게 나타나는 것이 특징적이었다. 이 결과는 토양층 뿐만 아니라 모암이 산성우의 완충용량을 가지고 있음을 나타내었다. A column study using artificial acid rain was conducted to evaluate the buffering capacities in soil layer and host rock. In an effort to compare the effect of composition of host rock, two valleys of which compositions of host rock are different were chosen within the study area and the pHs of the water flowing in the valleys were measured from May, 1996 to October, 1996. The pHs of the artificial acid rain prepared by adding appropriate amounts of both sulfuric and nitric acids to distilled water were 3,4,and 5, and the column effluents were analyzed for major cations and anions. The cation exchange capacities(CECs) of A Horizon and the B Horizon were 9.68 and 6.16 meq/100g, respectively. Compared to the B Horizon, the pH in the column effluent of A Horizon with larder CEC was higher. The sums of Ca^(2+), Mg^(2+) and Na^(+) in the column effluents gradually decreased, indicating the loss of CEC by acid rain. The field study showed that pHs of the surface water in the valleys increased as the water flows downwards. The magnitude of this buffering capacity was greater for the valley in which smectite in addition to kaolinite and illite was a weathered product of host rocks. This also indicates that host rock as well as soil layer retains the buffering capacity.

정보통신시장 유무선 통합서비스 도입과 기업 대응전략

송영화,류완하,김갑식 한국정보시스템학회 2004 情報시스템硏究 Vol.13 No.1

Fixed-mobile convergence services can be defined as the combination of previously separate fixed and mobile services, and networks and commercial practices. Examples of fixed-mobile convergence services include single voice-mail box, single number and unified messaging across fixed and mobile networks. Recently as more voice is transferred to mobile networks, convergence services between fixed and mobile become more important. In Korea convergence services are only starting to become established, and are likely to become an important part of any operator's offering. In this paper, we search the different levels of fixed-mobile convergence services and the trends and regulations for fixed-mobile convergence services in major countries. And at the same time, we also suggest the corresponding Marketing strategies by operators related to fixed-mobile convergence services.