Vegetation change and emerging research feedback for Korean National Long Term Ecological Research (KNLTER)

Cho, Yong-Chan,Lee, Chang-Seok,Cho, Hyun-Je,Lee, Kyu-Song,Park, Pil-Sun The Ecological Society of Korea 2011 Journal of Ecology and Environment Vol.34 No.1

Various responses of forest ecosystems to climate change underscore the need to improve our understanding of the environmentally-driven changes in forests, most effectively by long-term monitoring protocols. We have explored vegetation dynamics based on changes in community structure, species composition, diversity and demographics in four Korean National Long Term Ecological Research (KNLTER) sites--Mt. Nam, Mt. Jeombong, Mt. Worak, and Mt. Jiri--between 2004 and 2009. Most of the sites and forests studied exhibited increments in total basal area, but this was not observed in Quercus mongolica forests in Mt. Nam and Mt. Worak. Stem density exhibited various changes. Altitude gradient was the representative factor in differences in species composition. Two patterns of compositional change--convergence and divergence--were detected. The vegetation of Mt. Nam and Q. mongolica community of Mt. Work showed relatively larger changes in composition. However, in the other sites, few changes were observed. Changes of species richness were not notable except for Mt. Nam, where three species were added in the pine forest, whereas one species disappeared in the oak forest. In the oak forests, mortality rate was as follows (in descending order): Mt. Nam (25.5%), Mt. Jeombong (24.3%), Mt. Worak (16.4%) and Mt. Jiri (0.8%). In the pine forest, the recruitment rate was as follows (in descending order): Mt. Nam (63.7%), Mt. Worak (12.9%), Mt. Jeombong (7.6%) and Mt. Jiri (7.3%). The mortality rate and change rate of basal area were strongly negatively correlated (r = -0.9, P = 0.002), and the recruitment rate and change rate of density were positively correlated (r = 0.77, P = 0.026). In the KNLTER sites, larger vegetation changes were attributed to anthropogenic activities such as salvage logging. Suppression or competition for resources would also affect these changes. Research suggestions such as monitoring to clarify the causes of species mortality were discussed.

Projections of summertime ozone concentration over East Asia under multiple IPCC SRES emission scenarios

Lee, Jae-Bum,Cha, Jun-Seok,Hong, Sung-Chul,Choi, Jin-Young,Myoung, Ji-Su,Park, Rokjin J.,Woo, Jung-Hun,Ho, Changhoi,Han, Jin-Seok,Song, Chang-Keun Elsevier 2015 Atmospheric environment Vol.106 No.-

<P><B>Abstract</B></P> <P>We have developed the Integrated Climate and Air Quality Modeling System (ICAMS) through the one-way nesting of global–regional models to examine the changes in the surface ozone concentrations over East Asia under future climate scenarios. Model simulations have been conducted for the present period of 1996–2005 to evaluate the performance of ICAMS. The simulated surface ozone concentrations reproduced the observed monthly mean concentrations at sites in East Asia with high R<SUP>2</SUP> values (0.4–0.9), indicating a successful simulation to capture both spatial and temporal variability. We then performed several model simulations with the six IPCC SRES scenarios (A2, A1B, A1FI, A1T, B1, and B2) for the next three periods, 2016–2025 (the 2020s), 2046–2055 (the 2050s), and 2091–2100 (the 2090s). The model results show that the projected changes of the annual daily mean maximum eight-hour (DM8H) surface ozone concentrations in summertime for East Asia are in the range of 2–8 ppb, −3 to 8 ppb, and −7 to 9 ppb for the 2020s, the 2050s, and the 2090s, respectively, and are primarily determined based on the emission changes of NO<SUB>x</SUB> and NMVOC. The maximum increases in the annual DM8H surface ozone and high-ozone events occur in the 2020s for all scenarios except for A2, implying that the air quality over East Asia is likely to get worse in the near future period (the 2020s) than in the far future periods (the 2050s and the 2090s). The changes in the future environment based on IPCC SRES scenarios would also influence the change in the occurrences of high-concentrations events more greatly than that of the annual DM8H surface ozone concentrations. Sensitivity simulations show that the emissions increase is the key factor in determining future regional surface ozone concentrations in the case of a developing country, China, whereas a developed country, Japan would be influenced more greatly by effects of the regional climate change than the increase in emissions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Change in ozone level is determined by the combination of NO<SUB>x</SUB> and NMVOC emissions. </LI> <LI> Ozone level over East Asia would get worse in the near future (the 2020s) than far future. </LI> <LI> A high-concentration event generally increases and more frequently occurs in the future. </LI> <LI> Change in ozone air quality in a developing country depends more on emissions change. </LI> <LI> Change in ozone air quality in a developed country depends more on climate change. </LI> </UL> </P>

Which Environmental Factors Caused Lammas Shoot Growth of Korean Red Pine?

Lee, Chang-Seok,Song, Hye-Gyung,Kim, Hye-Soo,Lee, Bit-Na-Ra,Pi, Jeong-Hoon,Cho, Yong-Chan,Seol, Eun-Sil,Oh, Woo-Seok,Park, Sung-Ae,Lee, Seon-Mi The Ecological Society of Korea 2007 Journal of Ecology and Environment Vol.30 No.1

Lammas growth, a rare phenomenon for Korean red pine (Pinus densiflora), occurred in 2006. Lammas shoots showed higher frequency and longer length in Seoul's hotter urban center than in urban boundary or suburban forest sites. Frequency and length showed a close correlation with urbanization density and vegetation cover expressed in NDVI. Air temperature in the late summer of 2006 was more than $1^{\circ}C$ higher than an average year. Of the predominant environmental signals that modulate bud flush, only temperature changed significantly during the year. Differences in temperature between the urban centers, urban boundaries and suburban forests correlated with varying land-use density. The rise in temperature likely spurred lammas growth of the Korean red pine. Symptoms of climate change are being detected throughout the world, and its consequences will be clearer in the future. Considerate interest in the responses of ecological systems to the variable changes is required to prepare for unforeseeable crises. Monitoring of diverse ecological phenomena at Long Term Ecological Research sites could offer harbingers of change.

Allogenic succession of Korean fir (<i>Abies koreana Wils.</i>) forests in different climate condition

Lim, Chi Hong,An, Ji Hong,Jung, Song Hie,Lee, Chang Seok Springer Japan 2018 Ecological research Vol.33 No.2

<P><B>Abstract</B></P><P>This study was conducted to clarify the changes in vegetation that occurred due to changing environmental factors, especially climate, at Korean fir (<I>Abies koreana</I>) stands with different climatic conditions established on Mt. Halla, which is located on a southern island of South Korea. The difference of species composition between sites was large and depended on elevation and slope aspect at lower elevations, whereas not as much among stands or between sites at the highest elevations of each slope aspect. It was interpreted that differences and similarities among sites were dominated by the microclimate determined by the topographic conditions of each site. The result of vegetation dynamics analysis predicted that the Korean fir forests would be replaced by temperate forests such as Mongolian oak (<I>Quercus mongolica</I>) forests or shade intolerant forests composed of early successional species such as Korean cherry (<I>Prunus maximowiczii</I>) and Spreading yew (<I>Taxus cuspidata</I>) at lower elevations, while would continuously persist at the highest elevations. We interpreted the vegetation changes appeared at the lower elevations as an allogenic succession, as the recent rapid climate changes directly and indirectly dominated the change. The species distribution modeling predicted that the distributional range of Korean fir would decrease to 13.4 and 10.1% of the current distribution in 2050 and 2070, respectively. Further, the distribution modeling showed that the sites located at lower elevations would no longer be within the distributional range of Korean fir forest, and those at the highest elevations would be sparsely scattered in fragmented states.</P>

흰쥐에서 사염화 탄소(CCl4)에 의한 간섬유화의 유도

김병호,이정일,김효종,김영관,장린,동석호,장영운,송일한 대한소화기학회 1992 대한소화기학회지 Vol.24 No.6

Experimental model of hepatic fibrosis is importent contributions to the understanding of cellular and molecular mechanisms underlying excessive accumulation of extracellular matrix in the liver. Carbon tetrachloride (CCl₄) is one of the oldest and most widely used toxin for experimental induction of hepatic fibrosis in laboratory animals. In this study, We intended to induce the hepatic fibrosis in the rat by the intragastric CCl₄/ phenobarbtal treatment once a week for 12 weeks and the administration dosage of CCl₄ in each week was determined by the daily body weight change. Liver function and histologic change were examined just after 12-week treatment in group Ia (9 rats, Phenobarbital treatment only) and II (18 rats, CCl₄/phenobarbital treatment), and liver function and the irreversibility o histologic change were examined 12 weeks after 12-week treatment in group Ib (9 rats, phenobarbital treatment only) and III (18 rats, CCl₄/phenobarbital treatment). 1) Death rate after 12-week treatment was 11% in group Ⅰ, 56% in group Ⅱ and 50% in group Ⅲ. and the highest rate was at 1 week. that is 33 o each in group Ⅱ and Ⅲ. 2) Tatal protein, alkaline phosphatase, alanine aminotransferase and portal venous pressure were significantly increased in group Ⅱ compared with that in group Ⅰa, but it was only portal venous pressure that was increased in group Ⅲ than in group Ⅰb, 3) The gross finding of micronodular change was shown in 88% of group Ⅱ, 71% of group Ⅲ, but none of group Ⅰ. The microscopic finding of hepatic fibrosis was found in all of group Ⅱ and Ⅲ, but none of group Ⅰ. The severe form of hepatic fibrosis suggesting cirrhosis was found in group Ⅱ and Ⅲ, 12% and 29% respectively. In our study, mortality rate was high within 1 week after CCl₄ treatment, which resulted in half survival rate after 12-week treatment. We also experienced the loin rate of severe fibrotic changes in surviving rats. In the future, in order to produce a severe irreversible fibrotic change with low mortality in inducing hepatic fibrosis with CCl₄/phenobarbital treatment in the rat, adequate detemination of the initial dose of CCl₄ and appropriate choice of administration route of CCl₄ were thought to be needed.

Control of Reversible Self-Bending Behavior in Responsive Janus Microstrips

Oh, Myung Seok,Song, Young Shin,Kim, Cheolgyu,Kim, Jongmin,You, Jae Bem,Kim, Taek-Soo,Lee, Chang-Soo,Im, Sung Gap American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.13

<P>Here, we demonstrate a simple method to systematically control the responsive self-bending behavior of Janus hydrogel microstrips consisting of a polymeric bilayer with a high modulus contrast. The Janus hydrogel microstrips could be easily fabricated by a simple micromolding technique combined with an initiated chemical vapor deposition (iCVD) coating, providing high flexibility in controlling the physical and chemical properties of the microstrips. The fabricated Janus hydrogel microstrip is composed of a soft, pH-responsive polymer hydrogel layer laminated with a highly cross-linked, rigid thin film, generating a geometric anisotropy at a micron scale. The large difference in the elastic moduli between the two layers of the Janus microstrips leads to a self-bending behavior in response to the pH change. More specifically, the impact of the physical and chemical properties of the microstrip on the self-bending phenomena was systematically investigated by changing the thickness and composition of two layers of the microstrip, which renders high controllability in bending of the microstrips. The curvature of the Janus microstrips, formed by self-bending, highly depends on the applied acidity. A reversible, responsive self-bending/ unbending exhibits a perfect resilience pattern with repeated changes in pH for 5 cycles. We envision that the Janus microstrips can be engineered to form complex 3D microstructures applicable to various fields such as soft robotics, scaffolds, and drug delivery. The reliable responsive behaviors obtained from the systematic investigation will provide critical information in bridging the gap between the theoretical mechanical analysis and the chemical properties to achieve micron-scale soft robotics.</P>

von Recklinghausen씨 병에서 속발된 악성신경초종 : 1예 보고

유재형,서중석,김정란,송계용,장선택,박성일 중앙대부설한국의과학연구소 1984 한국의과학 Vol.16 No.4

Gene Expression Analysis of the Bromobenzene Treated Liver with Non-hepatotoxic Doses in Mice

Lim, Jung-Sun,Jeong, Sun-Young,Hwang, Ji-Yoon,Park, Han-Jin,Cho, Jae-Woo,Song, Chang-Woo,Kim, Yang-Seok,Lee, Wan-Seon,Moon, Jin-Hee,Han, Sang-Seop,Yoon, Seok-Joo The Korean Society of Toxicogenomics and Toxicopro 2005 Molecular & cellular toxicology Vol.1 No.4

Bromobenzene (BB) is well known hepatotoxicant. Also, BB is an industrial solvent that arouses toxicity predominantly in the liver where it causes centrilobular necrosis. BB is subjected to Cytochrome P450 mediated epoxidation followed by either conjugation with glutathione, enzymatic hydrolysis or further oxidation. In this study, we focused on BB-induced gene expression at non-hepatotoxic dose. Mice were exposed to two levels of BB, sampled at 24 h, and hepatic gene expression levels were determined to evaluate dose dependent changes. When examining the toxic dose of BB treated group in other previous studies, genes related to heat shock protein, oxidative stress, and drug metabolism are expressed. Compared to these results, our study, in which non-toxic dose of BB was administrated, showed similar patterns as the toxic conditions above. The purpose of the study was to select genes that showed changes in relation to the differing dose through confirmation of the difference within transcriptomic boundaries, but those that are not detected by the existing classic toxicology tools in non-hepatotoxic dose.

감염 조절용 차단막의 두께가 광중합기의 중합광에 미치는 영향

장훈상,이석련,홍성옥,류현욱,송창규,민경산 大韓齒科保存學會 2010 Restorative Dentistry & Endodontics Vol.35 No.5

연구목적: 본 연구는 감염 조절용 차단막을 여러 겹으로 사용했을 때 광중합기의 광강도와 파장, light diffusion 등에 미치는 영향에 대해 조사하였다. 연구 재료 및 방법: 감염 조절용 차단막은 투명 랩 (크린랩)을 사용하였고 광중합기는 할로겐 광중합기 (Optilux 360)와 LED 광중합기 (Elipar FreeLight 2)를 사용하였다. 차단막을 1겹, 2겹, 4겹, 8겹으로 광중합기의 광섬유말단을 감싸고 휴대용 광강도 측정기 (Cure Rite)로 광중합기의 광강도를 측정하였다. 광중합기를 주문제작한 optical breadboard에 고정시킨 후 휴대용 spectroradiometer (CS-1000)를 이용하여 광중합기의 파장을 측정하였고, DSLR (Nikon D70s)을 이용하여 광중합기의 light diffusion을 사진 촬영하였다. 결과: 광강도 측정 결과는 차단막의 두께가 증가할수록 광강도가 유의하게 감소하였으나 할로겐 광중합기에서 1겹과 2겹 사이에는 유의차가 없었으며, 4겹 이상의 차단막을 투과할 때 광강도가 더 많이 감소하였다. 여러 겹의 차단막을 투과한 광중합기의 전체적인 파장 형태와 peak wavelength의 변화는 관찰되지 않았다. Light diffusion 사진 촬영 시, LED 광중합기에서는 차단막의 두께가 미치는 영향이 없었으나 할로겐 광중합기에서는 차단막을 4겹 사용했을 때부터 중합광이 조사되는 각도가 감소하기 시작하여 8겹 사용했을 때 통계적으로 유의하게 감소하는 것을 볼 수 있었다 (p < 0.05). 결론: 광중합형 복합레진을 광중합할 경우 감염 조절용 차단막이 찢어지는 경우를 대비하여 1겹으로 사용하기 보다는 2겹으로 사용하는 것이 환자간의 교차감염을 예방하는데 유리할 것으로 사료된다. Objectives: This study investigated the effect of infection control barrier thickness on power density, wavelength, and light diffusion of light curing units. Materials and Methods: Infection control barrier (Cleanwrap) in one-fold, two-fold, four-fold, and eightfold, and a halogen light curing unit (Optilux 360) and a light emitting diode (LED) light curing unit (Elipar FreeLight 2) were used in this study. Power density of light curing units with infection control barriers covering the fiberoptic bundle was measured with a hand held dental radiometer (Cure Rite). Wavelength of light curing units fixed on a custom made optical breadboard was measured with a portable spectroradiometer (CS-1000). Light diffusion of light curing units was photographed with DSLR (Nikon D70s) as above. Results: Power density decreased significantly as the layer thickness of the infection control barrier increased, except the one-fold and two-fold in halogen light curing unit. Especially, when the barrier was four-fold and more in the halogen light curing unit, the decrease of power density was more prominent. The wavelength of light curing units was not affected by the barriers and almost no change was detected in the peak wavelength. Light diffusion of LED light curing unit was not affected by barriers, however, halogen light curing unit showed decrease in light diffusion angle when the barrier was four-fold and statistically different decrease when the barrier was eight-fold (p < 0.05). Conclusions: It could be assumed that the infection control barriers should be used as two-fold rather than one-fold to prevent tearing of the barriers and subsequent cross contamination between the patients.

대퇴골두 골괴사를 동반한 슬관절 골괴사 : 증례 보고

송준민,이병일,나수균,신영수,최창욱,박종석,권희 순천향의학연구소 1996 Journal of Soonchunhyang Medical Science Vol.2 No.1

본 순천향대학교 의과대학 정형외과학 교실에서는 2명의 환자에서 발견된 대퇴골두 골괴사와 함께 발생한 양측 슬관절 골괴사를 경험하였기에 보고하는 바이다. 대퇴골두 골괴사가 있는 환자에서 슬관절 동통을 호소하는 경우 연관통 등으로 여겨 간과하기 쉬우며, 대개 고관절의 통증으로 체중부하 보행이 어려운 경우가 많아 통증이 약하게 나타나기도 하기 때문에 관심을 가지고 슬관절 골괴사를 동반하는지 여부를 판단하여야 할 것이다. Osteonecrosis of the knee associated with osteonecrosis of the femoral head was very rare and reported cases were quite rare. We have experienced two cases of osteonecrosis of both knees associated with osteonecrosis of the femoral head. One is a 44-year-old man who had avascular necrosis of the righ femoral head and osteonecrosis of both knees, femoral condyle and metaphysis of proximal tibia. Another case is a 39-year-old man who had osteonecrosis of both femoral head and osteonecrosis of the both knees, medial condyles of both tibias. They were treated with total hip replacement arthroplasty for avascular necrosis of the femoral head and conservatively for osteonecrosis of the knee. If a person complains of pain in hip and knee simultaneously, we should pay attention and rule out osteonecrosis of the knee.