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Patterns and determinants of plant richness by elevation in a mountain ecosystem in South Korea: area, mid-domain effect,climate and productivity

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Journal of Forestry Research 2015年第4期26卷 905-917页

作者： Chang-Bae lee Jung-Hwa Chun Korea Green Promotion Agency 121 DunsanbukroSeoguDaejeon 302-831Republic of Korea Division of Forest Ecology Korea Forest Research Institute57 HoegiroDongdaemunguSeoul 130-712Republic of Korea

We examined patterns of plant species richness on an elevation gradient and evaluated the effects of cli- matic variables including mean annual temperature and precipitation, area, the mid-domain effect and productivity on species richness along two transects on Mt. Seorak, South Korea. A total of 235 plant species of 72 families and 161 genera were recorded from 130 plots along the two transects. Two different patterns, monotonic decline and a unimodal shape, were observed for woody plants with the change in elevation along the two transects, whereas multimodal patterns were observed for all plant species considered together and for herbaceous plants. Area and productivity showed significant relationships with total plant richness. Climatic variables were better predictors than other variables for variation by elevation in woody plant richness, whereas productivity was a more important variable for herbaceous plant richness. Although area was an important variable for predicting species richness pat- terns, the effects differed by transect and plant group. No empirical evidence was linked to the mid-domain *** elevational patterns may characterize different groups in the same taxon and there might be fundamental differences in the mechanisms underlying these richness patterns.

关键词： Area Climatic variables Elevationalpatterns Plant richness Productivity

Clustering Reference Images Based on Covisibility for Visual Localization

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Computers, Materials & Continua 2023年第5期75卷 2705-2725页

作者： Sangyun lee Junekoo Kang Hyunki Hong School of Integrative Engineering Chung-Ang UniversityHeukseok-ro 84Dongjak-kuSeoul06973Korea School of Software Chung-Ang UniversityHeukseok-ro 84Dongjak-kuSeoul06973Korea

In feature-based visual localization for small-scale scenes,local descriptors are used to estimate the camera pose of a query *** large and ambiguous environments,learning-based hierarchical networks that employ local as well as global descriptors to reduce the search space of database images into a smaller set of reference views have been ***,since global descriptors are generated using visual features,reference images with some of these features may be erroneously *** order to address this limitation,this paper proposes two clustering methods based on how often features appear as well as their *** both approaches,the scene is represented by voxels whose size and number are computed according to the size of the scene and the number of available *** the first approach,a voxel-based histogram representing highly reoccurring scene regions is generated from reference images.A meanshift is then employed to group the most highly reoccurring voxels into place clusters based on their spatial *** the second approach,a graph representing the covisibility-based relationship of voxels is *** matching is performed within the reference image clusters,and a perspective-n-point is employed to estimate the camera *** experimental results showed that camera pose estimation using the proposed approaches was more accurate than that of previous methods.

关键词： Visual localization deep learning voxel representation clustering covisibility meanshift graph structure

Deep Learning Approach for Cosmetic Product Detection and Classification

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Computers, Materials & Continua 2021年第10期69卷 713-725页

作者： Se-Won Kim Sang-Woong lee Department of IT Convergence Engineering Gachon UniversitySeongnam13120Korea Department of Software Gachon UniversitySeongnam13120Korea

As the amount of online video content is increasing,consumers are becoming increasingly interested in various product names appearing in videos,particularly in cosmetic-product names in videos related to fashion,beauty,and ***,the identification of such products by using image recognition technology may aid in the identification of current commercial *** this paper,we propose a two-stage deep-learning detection and classification method for cosmetic ***,variants of the YOLO network are used for detection,where the bounding box for each given input product is predicted and subsequently cropped for *** use four state-of-the-art classification networks,namely ResNet,InceptionResNetV2,DenseNet,and EfficientNet,and compare their ***,we employ dilated convolution in these networks to obtain better feature representations and improve *** experiments demonstrate that YOLOv3 and its tiny version achieve higher speed and ***,the dilated networks marginally outperform the base models,or achieve similar performance in the worst *** conclude that the proposed method can effectively detect and classify cosmetic products.

关键词： Cosmetic product detection cosmetic product classification deep learning

Late Quaternary Paleoclimatic Change in the Ulleung Basin,East Sea,Korea

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 263-269页

作者： Young-Suk BAK Young-Up lee The Earth and Environmental System Research Center Chonbuk National University Jeonju 54896 South Korea

Paleoclimatic changes in the late Quaternary sediments deposited in the East Sea were analyzed by studying diatoms. A total of 95 species belonging to 47 genera were identified from the Core02GHP-02 of the Ulleung Basin in the East Sea, Korea. In the Core 02GHP-02, U-Oki（169–181 cm; 9.3 ka）, AT（464–465.5 cm; 22 ka） and U–Ym（556–559 cm; 33 ka） tephra layers were recognized. The chronological divisions of 02GHP-02 may be correlated with the climatic changes from the glacial interval（730–620 cm; MIS3）, to interstadial（620–500 cm; MIS3）, to the last glacial maximum（500–390 cm; MIS 2）, to the deglaciation（390–290 cm; MIS 2）, to the late glacial（290–190 cm; MIS 1）, and to the Holocene（190–10 cm; MIS 1）. It is speculated that diatoms were rarely found during the glacial interval when the 02GHP-02 core was deposited; during the interstadial（MIS 3） and deglaciation, a mixture of warm-water and cold-water species were found. In particular, Fragilariopsis doliolus seems to have appeared in the East Sea after 8 ka BP. In the lower layers of the Holocene deposits, cold-water species such as Neodenticula seminae were frequently found, while in the upper layers, warm-water species such as Hemidiscus cuneiformis were found in relatively large abundance. Therefore, the findings indicate that the climate became warmer during the transition from the lower layer to the upper layer of the Holocene deposits.

关键词： diatoms paleoclimatic change late Quaternary glacial interval MIS

Regulation of DNA break repair by transcription and RNA

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Science China(Life Sciences) 2017年第10期60卷 1081-1086页

作者： Jian Ouyang Li Lan lee Zou Massachusetts General Hospital Cancer Center Harvard Medical School Boston MA 02129 USA University of Pittsburgh Cancer Institute University of Pittsburgh School of Medicine Pittsburgh PA 15213 USA Department of Microbiology and Molecular Biology University of Pittsburgh School of Medicine Pittsburgh PA 15219 USA Department of Pathology Massachusetts General Hospital Harvard Medical School Boston MA 02115 USA

Repair of DNA double-strand breaks(DSBs) via the homologous recombination(HR) pathway is a highly regulated process. A number of proteins that participate in HR are intricately modulated by the cell cycle and chromatin environments of DSBs. Recent studies have revealed a clear impact of transcription on HR in transcribed regions of the genome. Several models have been put forth to explain how the process of transcription and/or its RNA products may influence HR. Here we discuss the results and models from these studies, presenting an emerging view of transcription-coupled DSB repair.

关键词： DNA break repair transcription RNA

Diversity patterns and phylogenetic structure of vascular plants along elevational gradients in a mountain ecosystem, South Korea

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Journal of Mountain Science 2018年第2期15卷 280-295页

作者： CHUN Jung-Hwa lee Chang-Bae Division of Forest Ecology National Institute of Forest Science Global Resources Division Korea Forestry Promotion Institute

Recently, a phylogenetic diversity and community structure analysis as complementary to species-centric approaches in biodiversity studies provides new insights into the processes of community assembly. In this study, we analyzed species and phylogenetic diversity and community structures for woody and herbaceous plants along two elevational transects on Mt. Baekhwa, South Korea. The species richness and phylogenetic diversity of woody plants showed monotonic declining patterns with increasing elevation along all transects, whereas herbaceous plants showed different patterns, such as no relationship and a reversed unimodal pattern, between the study transects. The main drivers of these patterns were climate and habitat variables for woody and herbaceous plants, respectively. In addition, the phylogenetic community structure primarily showed phylogenetic clustering regulated by deterministic processes, especially environmental filtering, such as climate or habitat factors, along the two transects, although herbaceous plants along a transect depicted phylogenetic randomness as a result of a neutral process. Our findings suggest that deterministic and neutral processes may simultaneously control the community structures along small-scale elevational gradients such as local transects, although the deterministic process may be the predominant type.

关键词： Community structure Deterministicprocess Elevational gradient Neutral process Phylogenetic diversity Species richness

Fossil-Winged Fruits of Fraxinus(Oleaceae) and Liriodendron(Magnoliaceae) from the Duho Formation,Pohang Basin,Korea

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Acta Geologica Sinica(English Edition) 2009年第5期83卷 845-852页

作者： Seung-Ho JUNG Seong-Joo lee Department of Geology Kyungpook National UniversityDaegu 702-701Korea

A total of 16 specimens of fossil-winged fruits were found from the Middle Miocene marine deposits, Duho Formation, Pohang Basin, Korea. They were identified into two structurally different groups： 15 specimens into a winged fruit of Fraxinus, and one specimen of Liriodendron. The most samaras （13 specimens） were identified as Fraxinus oishii, which is characterized by narrowly ovate or ovate-elliptic shapes that are 2.7-3.6 cm in length and 0.7-1 cm in width （i/w ratio=3.4-4）. The apexes of the Fraxinus oishii samara are round or slightly emarginated, and a seed of the samara is always located at the base, of which the general shape is narrow rhombic-ellipsoidal. The seed is 1.2-2 cm long and 0.5-0.7 cm wide. Two specimens are different from the samara of Fraxinus oishii. They have a 6.6 length/width ratio （3.3 cm long and 0.5 cm wide）, and thus, are temporarily classified into the Fraxinus sp. One specimen was recognized as a winged seed of Liriodendron meisenense. The wing is broadly lanceolate to elliptic in shape, has a smooth, acute apex, and is approximately 3 cm long and 0.7 cm wide. Samaras of Fraxinus oishii and Liriodendron meisenense were early reported from the Middle Miocene deposits from North Korea, but these specimens are the first discovery in South Korea. Further study of the Duho Formation may connect flora relationships between North and South Korea.

关键词： winged fruits Fraxinus Liriodendron Middle Miocene Pohang Basin Korea

Mismatching between nest volume and clutch volume reduces egg survival and fledgling success in black-tailed gulls

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Current Zoology 2016年第5期62卷 451-456页

作者： Who-Seung lee Jeong-Chil Yoo Korea Institute of Ornithology and Department of Biology Kyung Hee University Seoul 02447 Korea Center for Stock Assessment Research University of California Santa Cruz Santa Cruz CA 95080 USA

A longstanding suggestion posits that parents prefer to match nest volume and clutch size （clutch volume）, but few studies have tested this in colonial seabirds that nest in the open. Here, we demonstrate the effects of nest-clutch volume matching on egg survival, hatching, and fledgling success in black-tailed gulls Larus crassirostris on Hongdo Island, Korea. We show that the volume mismatch, defined as the difference between nest volume and total egg volume （the sum of all eggs＇ volume in the clutch）, was positively related to egg and chick mortality caused by predation, but was not significantly related to hatching success incurred by insulation during the incubation period. Although nest volume was negatively related to laying date, we found that the mismatch was positively related to laying date. Our results support the claim that well-matched nest-clutch volume may contribute to survival of eggs and chicks, and ultimately breeding success.

关键词： black-tailed gulls clutch size egg survival fledgling success nest volume.

Global public concern of childhood and adolescence suicide:a new perspective and new strategies for suicide prevention in the post-pandemic era

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World Journal of Pediatrics 2024年第9期20卷 872-900页

作者： Soeun Kim Jaeyu Park Hyeri lee Hayeon lee Selin Woo Rosie Kwon Sunyoung Kim Ai Koyanagi lee Smith Masoud Rahmati Guillaume Fond Laurent Boyer Jiseung Kang Jun Hyuk lee Jiyeon Oh Dong Keon Yon Center for Digital Health Medical Science Research InstituteKyung Hee University College of MedicineSeoulSouth Korea Department of Precision Medicine Kyung Hee University College of MedicineSeoulSouth Korea Department of Regulatory Science Kyung Hee UniversitySeoulSouth Korea Department of Family Medicine Kyung Hee University Medical CenterKyung Hee University College of MedicineSeoulSouth Korea Research and Development Unit Parc Sanitari Sant Joan de DeuBarcelonaSpain Centre for Health Performance and WellbeingAnglia Ruskin UniversityCambridgeUK Department of Physical Education and Sport Sciences Faculty of Literature and Human SciencesLorestan UniversityKhoramabadIran Department of Physical Education and Sport Sciences Faculty of Literature and HumanitiesVali-e-Asr University of RafsanjanRafsanjanIran CEReSS-Health Service Research and Quality of Life Center Assistance Publique-Hôpitaux de MarseilleAix Marseille UniversityMarseilleFrance Department of Anesthesia Critical Care and Pain MedicineMassachusetts General HospitalBostonMAUSA Division of Sleep Medicine Harvard Medical SchoolBostonMAUSA Health and Human Science University of Southern CaliforniaLos AngelesCAUSA Department of Medicine Kyung Hee University College of MedicineSeoulSouth Korea Department of Pediatrics Kyung Hee University Medical CenterKyung Hee University College of Medicine23 Kyungheedae-roDongdaemun-guSeoul02447South Korea

Background Suicide is the second leading cause of death in young people worldwide and is responsible for about 52,000 deaths annually in children and adolescents aged 5-19 ***,social,psychological,and behavioral factors play important roles in suicide *** traumatic events such as the COVID-19 pandemic may contribute to suicidal behaviors in young people,there is a need to understand the current status of suicide in adolescents,including its epidemiology,associated factors,the influence of the pandemic,and management *** sources We investigated global and regional suicide mortality rates among children and adolescents aged 5-19 years using data from the Global Burden of Diseases,Injuries,and Risk Factors Study(GBD)*** suicide mortality rates from 1990 to 2019 were examined in 204 countries and territories across six World Health Organization(WHO)***,we utilized electronic databases,including PubMed/MEDLINE and Scopus,and employed various combinations of terms such as“suicide”,“adolescents”,“youth”,“children”,“risk factors”,“COVID-19 pandemic”,“prevention”,and“intervention”to provide a narrative review on suicide within the pediatric population in the post-pandemic *** Despite the decreasing trend in the global suicide mortality rate from 1990 to 2019,it remains *** mortality rates from suicide by firearms or any other specified means were both greater in ***,Southeast Asia had the highest suicide rate among the six WHO *** COVID-19 pandemic seems to contribute to suicide risk in young people;thus,there is still a strong need to revisit appropriate management for suicidal children and adolescents during the *** The current narrative review integrates up-to-date knowledge on suicide epidemiology and the effects of the COVID-19 pandemic,risk factors,and intervention *** numerous studies have characterized trends in suicide among young people during the

关键词： COVID-19 Global Pandemic Suicide Children Adolescents