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Changes in Distribution of Debris Slopes and Vegetation Characteristics in Mudeungsan National Park (무등산국립공원의 암설사면 분포변화 및 식생 특성)

  • Seok-Gon Park;Dong-Hyo Kim
    • Korean Journal of Environment and Ecology
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    • v.37 no.1
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    • pp.1-12
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    • 2023
  • We analyzed the distribution area of debris slopes in Mudeungsan (Mt. Mudeung) National Park by comparing aerial photos of the past (1966) and the present (2017) and identified the vegetation characteristics that affect the change in the area of the debris slopes by investigating the vegetation status of the debris slopes and the surrounding areas. The area of debris slopes in Mt. Mudeung appears to have been reduced to a quarter of what it used to be. Debris slopes here have decreased at an average rate of 2.3 ha/yr over 51 years by vegetation covers. Notably, most of the small-area debris slopes in the low-inclination slopes disappeared due to active vegetation coverage. However, there are still west-facing, south-west-facing, south-facing, and large-area debris slopes remaining because the sun's radiant heat rapidly raises the surface temperature of rock blocks and dries moisture, making tree growth unfavorable. Because of these locational characteristics, the small-scale vegetation in the middle of Deoksan Stony Slope, which is the broadest area, showed distinct characteristics from the adjacent forest areas. Sunny places and tree species with excellent drying resistance were observed frequently in Deoksan Stony Slope. However, tree species with high hygropreference that grow well in valleys with good soil conditions also prevailed. In some of these places, the soil layer has been well developed due to the accumulation of fine materials and organic matter between the crevices of the rock blocks, which is likely to have provided favorable conditions for such tree species to settle and grow. At the top of Mt. Mudeung, on the other hand, the forest covered the debris slopes, where Mongolian oaks (Quercus mongolica) and royal azaleas (Rhododendron schlippenbachii), which typically grow in the highlands, prevailed. This area was considered favorable for the development of vegetation for the highlands because the density of rock blocks was lower than in Deoksan Stony Slope, and the soil was exposed. Moreover, ash trees (Fraxinus rhynchophylla) and Korean maple trees (Acer pseudosieboldianum) that commonly appear in the valley areas were dominant here. It is probably due to the increased moisture content in the soil, which resulted from creating a depressive landform with a concave shape that is easy to collect rainwater as rock blocks in some areas fell and piled up in the lower region. In conclusion, the area, density of the rock blocks, and distribution pattern of rock block slopes would have affected the vegetation development and species composition in the debris slope landform.

A Proposal for Simplified Velocity Estimation for Practical Applicability (실무 적용성이 용이한 간편 유속 산정식 제안)

  • Tai-Ho Choo;Jong-Cheol Seo; Hyeon-Gu Choi;Kun-Hak Chun
    • Journal of Wetlands Research
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    • v.25 no.2
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    • pp.75-82
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    • 2023
  • Data for measuring the flow rate of streams are used as important basic data for the development and maintenance of water resources, and many experts are conducting research to make more accurate measurements. Especially, in Korea, monsoon rains and heavy rains are concentrated in summer due to the nature of the climate, so floods occur frequently. Therefore, it is necessary to measure the flow rate most accurately during a flood to predict and prevent flooding. Thus, the U.S. Geological Survey (USGS) introduces 1, 2, 3 point method using a flow meter as one way to measure the average flow rate. However, it is difficult to calculate the average flow rate with the existing 1, 2, 3 point method alone.This paper proposes a new 1, 2, 3 point method formula, which is more accurate, utilizing one probabilistic entropy concept. This is considered to be a highly empirical study that can supplement the limitations of existing measurement methods. Data and Flume data were used in the number of holesman to demonstrate the utility of the proposed formula. As a result of the analysis, in the case of Flume Data, the existing USGS 1 point method compared to the measured value was 7.6% on average, 8.6% on the 2 point method, and 8.1% on the 3 point method. In the case of Coleman Data, the 1 point method showed an average error rate of 5%, the 2 point method 5.6% and the 3 point method 5.3%. On the other hand, the proposed formula using the concept of entropy reduced the error rate by about 60% compared to the existing method, with the Flume Data averaging 4.7% for the 1 point method, 5.7% for the 2 point method, and 5.2% for the 3 point method. In addition, Coleman Data showed an average error of 2.5% in the 1 point method, 3.1% in the 2 point method, and 2.8% in the 3 point method, reducing the error rate by about 50% compared to the existing method.This study can calculate the average flow rate more accurately than the existing 1, 2, 3 point method, which can be useful in many ways, including future river disaster management, design and administration.

Curcumin-induced Cell Death of Human Lung Cancer Cells (Curcumin에 의해 유도되는 인간 폐암 세포주의 세포사멸)

  • Hwasin Lee;Bobae Park;Sun-Nyoung Yu;Ho-Yeon Jeon;Bu Kyung Kim;Ae-Li Kim;Dong Hyun Sohn;Ye-Rin Kim;Sang-Yull Lee;Dong-Seob Kim;Soon-Cheol Ahn
    • Journal of Life Science
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    • v.33 no.9
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    • pp.713-723
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    • 2023
  • Lung cancer is a type of cancer that has the highest mortality rate. It is mainly classified into small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC). Chemotherapy is used to treat lung cancer, but long-term treatment causes side effects and drug resistances. Curcumin is a bright yellow polyphenol extracted from the root of turmeric. It has biological activities, such as anti-oxidant, anti-cancer, and anti-inflammatory effects. In this study, we observed differential cell death in human lung cancer cells. Based on the results, curcumin at 10, 30, and 50 μM exhibited a dose-dependent inhibition on the cell survival of several lung cancer cells, with minor differential phenotypes. In addition, apoptosis, autophagy, and reactive oxygen species (ROS) regeneration were observed through flow cytometry. Curcumin dose-dependently increased these phenotypes in A549 (NSCLC) and DMS53 (SCLC), which were restored by corresponding inhibitors. Western blotting was performed to measure the level of expression of apoptosis- and autophagy-related proteins. The results indicate that Bax, PARP, pro-caspase-3, and Bcl-2 were dose-dependently regulated by curcumin, with seemingly higher Bax/Bcl-2 ratios in DMS53. In addition, autophagic proteins, p-AKT, p62, and LC3B, were dose-dependently regulated by curcumin. ROS inhibition by diphenyleneiodonium reduced the induction of apoptosis and autophagy generated by curcumin. Taken together, it is suggested that curcumin induces apoptosis and autophagy via ROS generation, leading to cell death, with minor differences between human lung cancer cells.

A Study on the Effect of Improving Permeability by Injecting a Soil Remediation Agent in the In-situ Remediation Method Using Plasma Blasting, Pneumatic Fracturing, and Vacuum Suction Method (플라즈마 블라스팅, 공압파쇄, 진공추출이 활용된 지중 토양정화공법의 정화제 주입에 따른 투수성 개선 연구)

  • Geun-Chun Lee;Jae-Yong Song;Cha-Won Kang;Hyun-Shic Jang;Bo-An Jang;Yu-Chul Park
    • The Journal of Engineering Geology
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    • v.33 no.3
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    • pp.371-388
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    • 2023
  • A stratum with a complex composition and a distributed low-permeability soil layer is difficult to remediate quickly because the soil remediation does not proceed easily. For efficient purification, the permeability should be improved and the soil remediation agent (H2O2) should be injected into the contaminated section to make sufficient contact with the TPH (Total petroleum hydrocarbons). This study analyzed a method for crack formation and effective delivery of the soil remediation agent based on pneumatic fracturing, plasma blasting, and vacuum suction (the PPV method) and compared its improvement effect relative to chemical oxidation. A demonstration test confirmed the effective delivery of the soil remediation agent to a site contaminated with TPH. The injection amount and injection time were monitored to calculate the delivery characteristics and the range of influence, and electrical resistivity surveying qualitatively confirmed changes in the underground environment. Permeability tests also evaluated and compared the permeability changes for each method. The amount of soil remediation agent injected was increased by about 4.74 to 7.48 times in the experimental group (PPV method) compared with the control group (chemical oxidation); the PPV method allowed injection rates per unit time (L/min) about 5.00 to 7.54 times quicker than the control method. Electrical resistivity measurements assessed that in the PPV method, the diffusion of H2O22 and other fluids to the surface soil layer reduced the low resistivity change ratio: the horizontal change ratio between the injection well and the extraction well decreased the resistivity by about 1.12 to 2.38 times. Quantitative evaluation of hydraulic conductivity at the end of the test found that the control group had 21.1% of the original hydraulic conductivity and the experimental group retained 81.3% of the initial value, close to the initial permeability coefficient. Calculated radii of influence based on the survey results showed that the results of the PPV method were improved by 220% on average compared with those of the control group.

Cone Characteristics and Seed Quality among Harvest Times in the Clonal Seed Orchard of Larix kaempferi (낙엽송 클론 채종원에서 구과 채취시기에 따른 구과특성 및 종자품질)

  • Ye-Ji Kim;Da-Eun Gu;Gyehong Cho;Heeyoon Choi;Yeongkon Woo;Chae-Bin Lee;Sungryul Ryu;Hye-Joon Joo;Kyu-Suk Kang
    • Journal of Korean Society of Forest Science
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    • v.112 no.3
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    • pp.352-362
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    • 2023
  • Harvest time is one of the most important determining factors of seed quality, especially for species that produce seeds over irregular and long-term periods, such as Larix kaempferi. A cone collection plan must be established to increase seed production efficiency and stable mass production. We investigated seed qualities such as seed efficiency, germination rate, and T50 (germination speed), with 7 or 8 cone collection times at a clonal seed orchard of L. kaempferi in Chungju between 2021 and 2022. A multivariate analysis was then performed for the collected data. In early August, decreases in the moisture contents and browning of cones were observed. These were followed by a decrease in germination rate, with a peak at the end of September, but no clear trend was observed. The later the cones were harvested, the better the seed vigor (T50). However, the seed yield and efficiency decreased owing to increases in seed scattering and the number of insect-damaged seeds. As a result, the optimal time of seed harvest for the seed orchard was in early August. To produce uniform seedlings, insect damage must be reduced through timely control and harvest cones in early September. This shows that the degree of browning and moisture content of cones can be used as indicators of the timing of cone collection in L. kaempferi seed orchards.

Selection of Lentinula edodes Sawdust Cultivation Cultivars Suitable for Sawdust Block Medium Cultivation (사각블럭배지 재배에 적합한 표고 톱밥재배 품종 선발)

  • Min-Jun Kim;Yeun Sug Jeong;Eunjin Kim;Yeongseon Jang;Kang-Hyeon Ka
    • The Korean Journal of Mycology
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    • v.51 no.2
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    • pp.81-90
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    • 2023
  • The cultivation method of shiitake is divided into two methods: log cultivation and sawdust cultivation. Recently, the importance of sawdust cultivation has been highlighted due to problems such as environmental problems, rising labor costs, and a reduced labor force. Among the 24 Sawdust-cultivated Lentinula edodes cultivars in Korea stored by the National Institute of Forest Science, this study was conducted to select excellent cultivars under the sawdust block cultivation method. After inoculation, the sawdust mediums were cultured for 100 days (60 days in dark and then 40 days in light), and only Sanjo 712ho sprouted the primordia on the 10th day of light culture (total 70 days of cultivation). As a result of cultivation, the average total yield of the 24 cultivars were 1,816 g and Sanjo 712ho was 2,267 g. The fruiting body yield was the highest in Sanjo 713ho with 3,443 g followed by Sanjo 710ho (3,355 g). Sanlim 10ho, Sansanhyang, and Sanjo 716ho showed low production with 174, 238, and 214 g, respectively. As a result of investigating the morphological characteristics of the fruit bodies, the fresh weight of Sansanhyang and Bambithyang was about twice as heavy as the overall average, and Sulbaekhyang was about twice as light. Bambithyang was the largest and longest in diameter and length of the stipe, and the thickness of the stem was the thickest in Sanjo 716ho. As for the hardness of pileus, Bambithyang showed the highest value at 1,276 g/5 mm, and Sanjo 711ho showed the lowest value at 542 g/5 mm. In summary, Bambithyang showed the best fruiting body characteristics and Sanjo 713ho showed the highest yield in the sawdust block cultivation method. This study, the cultivar with shortened cultivation periods and cultivars with excellent morphological characteristics and high yields.

Phytoplankton Variability in Response to Glacier Retreat in Marian Cove, King George Island, Antarctica in 2021-2022 Summer (하계 마리안 소만 빙하후퇴에 따른 식물플랑크톤 변동성 분석)

  • Chorom Shim;Jun-Oh Min;Boyeon Lee;Seo-Yeon Hong;Sun-Yong Ha
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.5
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    • pp.417-426
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    • 2023
  • Rapid climate change has resulted in glacial retreat and increased meltwater inputs in the Antarctic Peninsula, including King George Island where Marian Cove is located. Consequently, these phenomena are expected to induce changes in the water column light properties, which in turn will affect phytoplankton communities. To comprehend the effects of glacial retreat on the marine ecosystem in Marian Cove, we investigated on phytoplankton biomass (chlorophyll-a, chl-a) and various environment parameters in this area in December 2021 and January 2022. The average temperature at the euphotic depth in January 2022 (1.41 ± 0.13 ℃) was higher than that in December 2021 (0.87 ± 0.17 ℃). Contrastingly, the average salinity was lower in January 2022 (33.9 ± 0.10 psu) than in December 2021 (34.1 ± 0.12 psu). Major nutrients, including dissolved inorganic nitrogen, phosphate, and silicate, were sufficiently high, and thus, did not act as limiting factors for phytoplankton biomass. In December 2021 and January 2022, the mean chl-a concentrations were 1.03 ± 0.64 and 0.66 ± 0.15㎍ L-1, respectively. The mean concentration of suspended particulate matter (SPM) was 24.9 ± 3.54 mgL-1 during the study period, with elevated values observed in the vicinity of the inner glacier. However, relative lower chl-a concentrations were observed near the inner glacier, possibly due to high SPM load from the glacier, resulting in reduced light attenuation by SPM shading. Furthermore, the proportion of nanophytoplankton exceeded 70% in the inner cove, contributing to elevated mean fractions of nanophytoplankton in the glacier retreat marine ecosystem. Overall, our study indicated that freshwater and SPM inputs from glacial meltwater may possibly act as main factors controlling the dynamics of phytoplankton communities in glacier retreat areas. The findings may also serve as fundamental data for better understanding the carbon cycle in Marian Cove.

Effects of GA3 Dipping of Time and Concentration on the Rachis Growth and Fruit Quality in 'Campbell Early' Grapevine (포도 '캠벨얼리'에서 GA3의 침지 시기와 농도에 의한 화수(花穗)생장 및 과실품질)

  • Moon, Byung-Woo;Lee, Young-Cheul;Nam, Ki-Woong;Moon, Young-Ji
    • Journal of Practical Agriculture & Fisheries Research
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    • v.16 no.1
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    • pp.55-66
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    • 2014
  • This study has been conducted to investigate the treatment time and concentration of GA3 solution dipping for labor saving in 'Campbell Early' grapevine. The rachis growth at harvest was reduced by GA3 solution dipping before 5 days flowering, and increased significantly by GA3 solution dipping treatment at full bloom and after 5 days full bloom. GA3 5, 10, 20 mg·L-1 dipping treatment before 5 days flowering and GA3 20 mg·L-1 treatment of full bloom and after 5 days full bloom showed a rachis twist phytotoxicity symptom. The optimum GA3 concentrations for rachis growth promotion without phytotoxicity were 5 mg·L-1 and 10 mg·L-1. The degree of compact berry, bloom, skin color, SSC and acidity at harvest by GA3 solution dipping treatment time between concentration were not different from those of control. But the fruit berry weight was decreased by before 5 days flowering treatment when compared with control. There were no differences in full bloom and after 5 days full bloom treatment. The occurrence percent of berry cracking at before 5 days flowering and after 5 days full bloom treatment were significantly increased by GA3 treatment. The bitter rot occurrence of berry at harvest was not affected by GA3 treatment. Total rachis length of fruit cluster was increased by full bloom and 5 days after full bloom treatment. The length of rachis increased without reference to them position at full bloom and 5 days after bloom treatment. Accordingly, GA3 5 mg·L-1 solution dipping treatment at full bloom and 5 days after full bloom were can be effectively for rachis growth promotion.

Studies on Improvement of Quality Wine of "Vitis amurensis RUPRECHT" ("개량머루" 과실주의 품질향상에 관한 연구)

  • Lee, B.Y.;Lee, Y.C.;Jung, H.W.;Lim, J.W.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.9 no.1
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    • pp.47-58
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    • 2007
  • New Wild Grape berry weighs approximately 3.7g, which is one fourth of the weight of the general grape wine (12.2g). The pH of New Wild Grape wine is around 3.34, which is lower by 0.3 than that (3.62) of general grape wine. It contains higher organic acids, so it has stronger sour taste. The sugar content of New Wild Grape is 17° Brix, which is higher than that (15° Brix) of general grape wine. The color of New Wild Grape is blackish, owing to the lower lightness, redness, and yellowness compared with those of general grape wine. Depending on the mixing with or without oak tree, there is little difference in the pH, organic acid, reducing sugar, and amount of alcohol after ripening for 1 year. In taste, New Wild Grape wine mixing with oak tree is evaluated better than that of the wine without oak tree. Especially, in the case of the wine mixing with oak tree's sawdust, the quality in color, taste, and smell became improved. After fermentation, the pH of New Wild Grape Wine ripened with oak tree charcoal increased from 3.82 to 3.86, as it gets more oak tree charcoal, and the organic acid decreased from 0.91㎖ to 0.86㎖. However, there is no difference in alcohol amount. Lightness in color tended to be reduced, whereas redness tended to be increased. Adding 3% of oak tree charcoal made the taste and smell improved. When fermenting New Wild Grape Wine with mixing 1% of oak tree's sawdust or 3% of oak tree charcoal, there is little difference in the pH and the organic acid, whereas there is a little difference in those of New Wild Grape Wine without addition of oak tree charcoal. As the addition of oak tree charcoal increased, the lightness and redness became higher. When fermenting New Wild Grape Wine with mixing 1% of oak tree's sawdust or 3% of oak tree charcoal in oak tree barre, the taste became improved.

A Comparative Toxicological Study of Dried Mylabris phalerata Extract and it's Modifier : Single Dose Toxicity on Male Mice (반묘(斑猫)와 가공반묘(加工斑猫)의 단회투여(單回投與) 독성에 대한 비교연구)

  • Roh, Heui-Mok;Kim, Seong-Mo;Choi, Hong-Sik
    • The Korea Journal of Herbology
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    • v.24 no.3
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    • pp.1-12
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    • 2009
  • Objectives : The objective of this study was to compare, the potency of toxicity of Cantharidin containing dried Mylabis phalerata (MP) extract and it's modifier. Methods : They were monitored at dosage level 2,000, 1,000, 500, 250 and 125 mg/kg, respectively. Changes of body weight, clinical signs, mortality, LD50, macroscopic changes of gastrointestinal tract and liver were observed after single oral dose of test articles with changes of serum Gastrin and Somatostatin levels. Results : Dosage-dependent decrease of body weight and/or gains were demonstrated in dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, the body weights were significantly increased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependently detected clinical signs in dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these clinical signs dramatically were decreased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependent increase of mortality rates were observed in dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, the mortalities were significantly decreased compared to that of equal dosage group of dried MP extract-dosing group. The LD50 of dried MP extract in male mice was dramaticlly increased in their modify, 265.86 vs 426.99 mg/kg. Dosage-dependently increase of number of hemorrhagic and/or erythematous spots detected in the gastrointestinal tracts of dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these abnormal spots were dramatically decreased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependently increase of degrees of enlargement and congestion detected in the liver of dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these abnormal signs were dramatically decreased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependently increase of serum gastrin levels of dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these abnormal increase were dramatically decreased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependently increase of serum somatostatin levels of dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these abnormal increase were dramatically decreased compared to that of equal dosage group of dried MP extract-dosing group. Conclusions : The toxicity of dried MP extract was reduced by their modify.