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Regeneration of pitch pine (Pinus rigida) stands inhibited by fire suppression in Albany Pine Bush Preserve, New York

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Journal of Forestry Research 2019年第1期30卷 233-242页

作者： chang-seok lee George R.Robinson Ingrid P.Robinson Hansol lee Department of Bio and Environment Technology Seoul Women's University State University of New York at Albany State University of New York

The Pine Barrens in New York State are dominated by pitch pine(Pinus ridgida) and scrub oaks(Quercus ilicifolia and Q. prinoides). With fire suppression over the last 90 years or so, P. rigida regeneration has become sparse, even in areas set aside to preserve this type of vegetation. We evaluated the effects of fire and an alternative disturbance(mechanical removal of vegetation)for increasing P. rigida regeneration in the Albany Pine Bush Preserve in eastern New York State. By comparing cover, diameter and height of P. rigida, Q. ilicifolia, ***, and Vaccinium spp.(blueberry) growing on the sites with a known fire history, we documented structural and compositional changes in the vegetation since its establishment. We also compared sites on which Quercus sprouts were controlled through mechanical removal. In the years following a disturbance, height and cover of Q. ilicifolia increased continuously and the species became increasingly competitive. Both the density of P. rigida seedlings and Vaccinium cover decreased significantly as the diameter and height of Quercus increased. Our results confirmed that the dominance by P. rigida could be attributed to periodic fires at intervals of 20–25 years. We conclude that removing Q. ilicifolia can favor P. rigida dominance on the barren without fire by releasing pine seedlings from competition.

关键词： Fire Mechanical removal Pine barren Pinus rigida Quercus ilicifolia Quercus prinoides Regeneration Safe site

Early recovery process and restoration planning of burned pine forests in central eastern Korea

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Journal of Forestry Research 2019年第1期30卷 243-255页

作者： Ji Hong An Chi Hong Lim Yong Chan Cho chang seok lee Department of Bio and Environmental Technology Seoul Women's University Division of Plant Conservation Korea National Arboretum

In central eastern Korea, there has been a continued effort to sustain pine forests because of their value for wood and mushroom production, as well as for other resources. Through the analysis of previously burned areas,we clarified the effects of fire on vegetation dynamics of pine forests by measuring changes in species composition,population structure, and the growth rates of major tree species. Vegetation analysis was conducted on a series of 100 m^2 plots established in Korean red pine(Pinus densiflora Siebold. & Zucc.) and Mongolian oak(Quercus mongolica Fisch. Ex Ledeb.) forests situated in three different topographic positions on slopes where fire severity varied. We confirmed that most pine trees will succumb to even a surface fire, whereas oak may be killed following high intensity or infrequent fires but will sprout and become dominant. Complete protection from fire favors other, more shade-tolerant deciduous hardwoods. Different restoration plans apply, based on observed vegetation responses for each topographic zone. Near the ridge top,where pine seed sources are most limited, it may be necessary to restore pine forests by planting and to control competing shrubs and herbs. At the mountain foot, where exotic species and species modified by hybridization have invaded aggressively, restoration that involves the introduction of natural vegetation is required. Mid-slope sites,where pine has been replaced by natural vegetation dominated by Mongolian oak, do not require any form of restorative treatment.

关键词： Vegetation succession Vegetation type Fire severity Fire disturbance Landscape structure

Deduction of a meteorological phenology indicator from reconstructed MODIS LST imagery

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Journal of Forestry Research 2020年第6期31卷 2205-2216页

作者： Chi Hong Lim Song Hie Jung Nam Shin Kim chang seok lee Department of Bio and Environmnetal Technology Graduate SchoolSeoul Women’s UniversitySeoul Republic of Korea Research Team on Ecological and Natural Map National Institute of EcologySeocheon Choongnam Republic of Korea Department of Bio and Environmnetal Technology Seoul Women’s UniversitySeoul Republic of Korea

Phenology is a valuable attribute of vegetation to assess the biological impacts from climate change.A challenge of phenological research is to obtain information on both high temporal resolution and fine spatial scale ***,we constructed an air temperature map based on temporal merging and spatial interpolation algorithms to overcome the cloud-related problem from the MODIS LST ***,we derived the accumulated growing degree days(AGDD)from the constructed mean air temperature map to use as a meteorological ***,we verified the indicator with the seasonal mean air temperature and the green-up date of a Quercus mongolica forest determined from the field-based *** AGDD threshold for each *** forest when the first leaf has unfolded was detected from the EXG trajectory extracted from digital camera images.A comparison between meteorological and MODIS-derived AGDD showed good agreement between *** was also high consistency between DoYs extracted from AGDD and EVI based on curvature K for *** forests of 30 sampling sites throughout South *** results prove that microclimatic factors such as elevation,waterbody,and land-use intensity were faithfully reflected in the reconstructed ***,the results of this study could be applied effectively in areas where microclimatic variation is very severe and for monitoring phenology of undergrowth,which is difficult to detect from reflectance imaging.

关键词： Climate change Digital camera Growing degree days MODIS Phenology Quercus mongolica

Evaluating the Discriminatory Power of DNA Barcodes in Panicoideae, Poaceae

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Journal of Agricultural Science and Technology(B) 2014年第7期4卷 533-544页

作者： Jeongran lee chang-seok Kim In-Yong lee Department of Crop Life Safety National Academy of Agricultural Science Rural Development Administration Suwon 441- 701Republic of Korea

DNA barcoding is a powerful technique for species identification with little morphological knowledge, by using short sections of DNA from a specific region of the genome. Two core barcode markers, rbcL and matK, and a supplementary nuclear ribosomal internal transcribed spacer region were used to examine the effectiveness of the markers for Poaceae barcoding using 133 individuals of 36 taxa across 23 genera of Korean Panicoideae. We also aimed to establish a DNA barcode database for the major weeds of Korean Panicoideae. All three markers revealed a good level of amplification and sequencing success. As a single DNA marker, the ITS region achieved the highest species resolution, followed by matK. Resolving power was increased when nrlTS was incorporated into the core barcode markers. The best resolving power was obtained with a combination of matK ＋ ITS with 89.7%, followed by rbcL ＋ matK ＋ ITS with 89.3%. Thus, rbcL may be not necessary as a DNA barcode for Panicoideae species identification, when considering cost and effectiveness. Instead, a combination of matK ＋ ITS is proposed as the most suitable DNA barcode for the species identification of Panicoideae, Poaceae. We conclude that DNA barcoding using a combination of matK ＋ ITS could be one of powerful techniques for the identification of Poaceae species, The barcode sequences were deposited to the National Center for Biotechnology Information （NCBI） database for public use.

关键词： Plant barcode Poaceae core barcode markers nrITS resolving power.

Efficacy of cap-assisted colonoscopy according to lesion location and endoscopist training level

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World Journal of Gastroenterology 2015年第20期21卷 6261-6270页

作者： Dong Jun Kim Hyung Wook Kim Su Bum Park Dae Hwan Kang Cheol Woong Choi Joung Boom Hong Byoung Hoon Ji chang seok lee Department of Internal Medicine Medical Research InstitutePusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology Pusan National University Yangsan Hospital Department of Internal Medicine Dong-eui Medical Center Department of Internal Medicine Bongseng Memorial Hospital

AIM: To evaluate the efficacy of cap-assisted colonoscopy(CAC) for detection of colorectal polyps and adenomas according to the lesion location and endoscopist training ***: Patients 20 years or older, who underwent their first screening colonoscopy in a single tertiary center from May 2011 to December 2012 were enrolled in this study. All patients underwent either CAC or standard colonoscopy(SC), and all of the procedures were performed by 11 endoscopists(8 trainees and 3 experts). All procedures were performed with highdefinition colonoscopes and narrow band imaging. The eight trainees had experiences of performing 150 to 500 colonoscopies, and the three experts had experiences of performing more than 3000 colonoscopies. A 4-mmlong transparent cap was attached to the end of a colonoscope in the CAC group. We retrospectively evaluated the number of polyps and adenomas, polyp detection rate(PDR), and the number of adenomas and adenoma detection rate(ADR) according to the lesion location and endoscopist training level between CAC and SC. We also evaluated the number of polyps and adenomas according to their size between CAC and ***: Overall, PDR and ADR using CAC were significantly higher than those using SC for both whole colon(48.5% vs 40.7%, P = 0.012; 35.7% vs 28.3%, P = 0.012) and right-side colon(35.3% vs 26.6%, P = 0.002; 27.0% vs 16.9%, P < 0.001). The number of polyps and adenomas per patient using CAC was significantly higher than that using SC for both the whole colon(1.07 ± 1.59 vs 0.82 ± 1.31, P = 0.008; 0.72 ± 1.32 vs 0.50 ± 1.01, P = 0.003) and right-side colon(0.66 ± 1.18 vs 0.41 ± 0.83, P < 0.001; 0.46 ± 0.97 vs 0.25 ± 0.67, P < 0.001). In the trainee group, the PDR and ADR using CAC were significantly higher than those using SC for both the whole colon(46.7% vs 39.7%, P = 0.040; 33.9% vs 26.0%, P =0.012) and right-side colon(34.2% vs 26.5%, P = 0.015; 25.3% vs 15.9%, P = 0.001). In the expert group, the PDR and ADR using CAC were si

关键词： Colonoscopy Cap-assisted colonoscopy Colonic polyps Adenoma Colorectal neoplasm

Aligned Ion Conduction Pathway of Polyrotaxane‑Based Electrolyte with Dispersed Hydrophobic Chains for Solid‑State Lithium–Oxygen Batteries

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Nano-Micro Letters 2025年第2期17卷 169-186页

作者： Bitgaram Kim Myeong‑chang Sung Gwang‑Hee lee Byoungjoon Hwang Sojung Seo Ji‑Hun Seo Dong‑Wan Kim Department of Materials Science and Engineering Korea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea School of Civil Environmental and Architectural EngineeringKorea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea Materials Science and Chemical Engineering Center Institute for Advanced Engineering(IAE)Yongin 17180Republic of Korea

A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety *** study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves ***-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain *** this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 *** situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen *** situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability *** present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.

关键词： Solid polymer electrolyte Lithium-oxygen batteries Polyrotaxane ion conductivity Hydrophobic chain

Combating Drug Resistance in Colorectal Cancer Using Herbal Medicines

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Chinese Journal of Integrative Medicine 2021年第7期27卷 551-560页

作者： lee Ga-Young lee Jin-seok Son chang-Gue lee Nam-Hun Department of Clinical Oncology Cheonan Korean Medicine Hospital of Daejeon UniversityCheonan31099Republic of Korea Liver&Immunology Research Center Dunsan Korean Medicine Hospital of Daejeon UniversityDaejeon35235Republic of Korea Department of Internal Medicine Graduated School of Korean MedicineUniversity of DaejeonDaejeon34520Republic of Korea

Colorectal cancer(CRC)is one of the most prevalent and lethal cancer types around the *** of the CRC patients are treated with chemotherapeutic drugs alone or ***,up to 90%of metastatic cancer patients experience the failure of treatment mostly because of the acquired drug resistance,which can be led to multidrug resistance(MDR).In this study,we reviewed the recent literature which studied potential CRC MDR reversal agents among herbal medicines(HMs).Among abundant HMs,6 single herbs,Andrographis paniculata,Salvia miltiorrhiza,Hedyotis diffusa,Sophora flavescens,Curcuma longa,Bufo gargarizans,and 2 formulae,Pien Tze Huang and Zhi Zhen Fang,were found to overcome CRC MDR by two or more different mechanisms,which could be a promising candidate in the development of new drugs for adjuvant CRC chemotherapy.

关键词： colorectal cancer drug resistance herbal medicine

Comparative study on discharge conditions in micro-hole electrical discharge machining of tungsten carbide (WC-Co) material

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中国有色金属学会会刊：英文版 2009年第B9期19卷 114-118页

作者： Hyun-seok TAK chang-Seung HA Dong-Hyun KIM Ho-Jun lee Hae-June lee Myung-chang KANG National Core Research Center for Hybrid Materials Solution Pusan National University Department of Electrical Engineering Pusan National University

WC-Co is used widely in die and mold industries due to its unique combination of hardness, strength and wear-resistance. For machining difficult-to-cut materials, such as tungsten carbide, micro-electrical discharge machining(EDM) is one of the most effective methods for making holes because the hardness is not a dominant parameter in EDM. This paper describes the characteristics of the discharge conditions for micro-hole EDM of tungsten carbide with a WC grain size of 0.5 μm and Co content of 12%. The EDM process was conducted by varying the condenser and resistance values. A R-C discharge EDM device using arc erosion for micro-hole machining was suggested. Furthermore, the characteristics of the developed micro-EDM were analyzed in terms of the electro-optical observation using an oscilloscope and field emission scanning electron microscope.

关键词：电火花加工碳化钨钴难切削材料硬质合金放电扫描电子显微镜微孔模具行业

Characteristic evaluation of Al_2O_3/CNTs hybrid materials for micro-electrical discharge machining

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 28-32页

作者： Hyun-seok TAK chang-Seung HA Ho-Jun lee Hyung-Woo lee Young-Keun JEONG Myung-chang KANG National Core Research Center for Hybrid Materials Solution Pusan National University Department of Electrical Engineering Pusan National University

The characteristic evaluation of aluminum oxide （A1203）/carbon nanotubes （CNTs） hybrid composites for micro-electrical discharge machining （EDM） was described. Alumina matrix composites reinforced with CNTs were fabricated by a catalytic chemical vapor deposition method. A1203 composites with different CNT concentrations were synthesized. The electrical characteristic of A1203/CNTs composites was examined. These composites were machined by the EDM process according to the various EDM parameters, and the characteristics of machining were analyzed using field emission scanning electron microscope （FESEM）. The electrical conductivity has a increasing tendency as the CNTs content is increased and has a critical point at 5% A1203 （volume fraction）. In the machining accuracy, many tangles of CNT in A1203/CNTs composites cause violent spark. Thus, it causes the poor dimensional accuracy and circularity. The results show that conductivity of the materials and homogeneous distribution of CNTs in the matrix are important factors for micro-EDM of A1203/CNTs hybrid composites.

关键词： A1203/CNTs hybrid materials micro-electrical discharge machining micro-hole electrical conductivity