• Rapid Communication in Photoscience
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• 제2권2호
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• pp.42-45
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• 2013

Natural photosynthesis utilizes solar energy to convert carbon dioxide and water to energy-rich carbohydrates. Substantial use of sunlight to meet world energy demands requires energy storage in useful fuels via chemical bonds because sunlight is intermittent. Artificial photosynthesis research focuses the fundamental natural process to design solar energy conversion systems. Nicotinamide adenine dinucleotide ($NAD^+$) and $NADP^+$ are ubiquitous as electron transporters in biological systems. Enzymatic, chemical, and electrochemical methods have been reported for NADH regeneration. As photochemical systems, visible light-driven catalytic activity of NADH regeneration was carried out using platinum nanoparticles, molecular rhodium and cobalt complexes in the presence of triethanolamine as a sacrificial electron donor. Pt nanoparticles showed photochemical NADH regeneration activity without additional visible light collector molecules, demonstrating that both photoactivating and catalytic activities exist together in Pt nanoparticles. The NADH regeneration of the Pt nanoparticle system was not interfered with the reduction of $O_2$. Molecular cobalt complexes containing dimethylglyoxime ligands also transfer their hydrides to $NAD^+$ with photoactivation of eosin Y in the presence of TEOA. In this photocatalytic reaction, the $NAD^+$ reduction process competed with a proton reduction.

• Journal of Forest and Environmental Science
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• 제32권3호
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• pp.237-252
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• 2016

Improved knowledge of the environmental factors affecting the natural regeneration of tree species in limestone forest is urgently required for species conservation. We examined the environmental factors and tree species characteristics that are important for colonization in diverse forest stands growing on a limestone hill in northern Thailand. Our analysis estimated the relative influence of forest structure and environmental factors on the regeneration traits of tree species. We established sixty-four $100-m^2$ plots in four forest stands on the limestone hill. We determined the species composition of canopy trees, regenerating seedlings, and saplings in relation to the physical environment. The relationships between environmental variables and tree species abundance were assessed by canonical correspondence analysis (CCA), and we used generalized linear mixed models to examine data on seedling/sapling abundances. The CCA ordination indicated that the abundance of tree species within the mixed deciduous forest was closely related to soil depth. The abundances of tree species growing within the sink-hole and hill-slope stands were positively related to the extent of rocky outcropping; light and soil moisture positively influenced the abundance of tree species in the hill-cliff stand. Physical factors had a greater effect on tree regeneration than did factors related to forest structure. Tree species, such as Ficus macleilandii, Dracaena cochinchinensis, and Phyllanthus mirabilis within the hill-cliff or sink-hole stand, colonized well on large rocky outcroppings that were well illuminated and had soft soils. These species regenerated well under conditions prevailing on the limestone hill. The colonization of several species in other stands was negatively influenced by environmental conditions at these sites. We found that natural regeneration of tree species on the limestone hill was difficult because of the prevailing combination of physical and biological factors. The influence of these factors was species dependent, and the magnitude of effects varied across forest stands.

• 한국산림과학회지
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• 제112권3호
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• pp.331-339
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• 2023

본 연구는 목재수확 유형에 따른 종자 유입 특성을 구명하여 천연갱신에 의한 소나무 후계림 조성 기술의 기초자료를 제공하고자 수행되었다. 이를 위해 모수작업(단목모수, 군상모수) 및 개벌작업(대상개벌 10 mㆍ20 mㆍ40 m, 군상개 벌 20 mㆍ30 mㆍ40 m)을 실시하여 시험지를 조성하고, 2014년부터 6년간 천연갱신지의 종자 유입 특성을 분석하였다. 소나무 종자는 대부분 10~11월 갱신상에 유입되었으며, 종자 결실이 좋은 해에는 80% 이상이 10월에 유입되었다. 목재수확 유형별 연평균 종자 유입량은 군상 모수작업지(296천립/ha/yr), 20 m 군상 개벌작업지(291천립/ha/yr), 10 m 대상 개벌 작업지(281천립/ha/yr) 순으로 많았다. 유입 종자 분포 균일성은 20 m 대상 개벌작업지(52.2), 20 m 군상 개벌작업지(52.9), 10 m 대상 개벌작업지(56.1) 순으로 분석되어 벌채 면적이 상대적으로 좁은 10 m 대상 개벌작업지와 20 m 군상 개벌작업지가 종자 유입량 및 분포 균일성이 높은 것으로 나타났다.

• 한국산림과학회지
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• 제104권4호
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• pp.543-548
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• 2015

단목모수, 군상모수, 군상개벌, 대상개벌 등의 천연갱신 방법이 적용된 소나무림의 nSSR 유전변이를 조사하였다. 작업(벌채) 전 성목과 작업 후 임내에서 자연 발생한 1년생 치수들의 유전다양성을 비교한 결과 큰 차이가 없는 것으로 나타났으며(성목: A=13.4; $A_e$=4.3; $H_o$=0.596; $H_e$=0.598, 치수: A=13.6; $A_e$=4.3; $H_o$=0.571; $H_e$=0.597), 각각의 작업종에서도 통계적으로 유의한 차이를 발견할 수 없었다. 성목과 치수의 유전분화 정도는 매우 낮은 것으로 나타났으며($F_{ST}$=0.002), 각 작업종별 유전분화 정도 역시 낮은 값($$F_{ST}{\leq_-}0.01$$)을 보여 작업 전, 후 임분의 유전구조 변화는 크지 않은 것으로 추정되었다. 결과적으로 본 연구가 수행된 소나무 임분의 경우 유전다양성과 유전적 조성 변화에 미치는 천연갱신 작업종의 효과가 두드러지지 않은 것으로 나타났다. 그러나, 천연갱신 작업종이 유전변화에 미치는 영향을 보다 정확하게 평가하기 위해서는 작업 후 남겨진 개체(모수)의 교배로부터 발생한 치수들의 시계열적 유전변이와 유전구조 변화를 지속적으로 추정할 필요가 있는 것으로 판단된다.

• 한국환경생태학회지
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• 제17권2호
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• pp.105-111
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• 2003

이 연구는 환경친화적이며 생태적 숲관리를 위한 활엽수의 조림기술을 개발하고자 강원도 홍천군 내면지역에 1979∼1982년에 대규모의 활엽수 조림단지를 조성했던 지역의 물푸레나무 조림지와 천연림으로 비교적 생장이 양호한 평창군 진부면 지역의 물푸레나무가 많은 천연활엽수림에 대한 임분구조 및 직경생장을 조사, 비교하였다. 조림 후 7, 8년까지의 직경생장에 임분간 유의차가 인정되었다. 연평균직경생장량은 맹아림에서 4.60mm/year로 최대값이었으며 다음으로 천연림의 물푸레나무가 4.59mm/year, 조림된 물푸레나무림에서는 4.18mm/year로 최소값을 보였다. 조림한 물푸레나무의 초기의 직경생장이 맹아갱신된 나무나 천연생의 나무보다 지극히 낮다는 것은 물푸레나무 나근묘의 식재는 성적이 매우 불량함을 나타낸다고 판단된다. 이러한 결과로 볼 때 물푸레나무림 갱신에서는 맹아, 천연하종, 직파조림 등의 다른 갱신법들도 적극 검토할 필요가 있다고 판단된다.

• 한국환경생태학회지
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• 제17권4호
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• pp.309-315
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• 2004

이 연구는 가래나무의 조림에 대한 성적평가와 개선대책을 마련하고자, 강원도 홍천군 내면지역에 1979-1982년에 대규모의 활엽수 조림단지를 조성했던 지역의 가래나무 조림지와 천연림으로 비교적 생장이 양호한 평창군 진부면 지역의 물푸레나무와 가래나무가 많은 활엽수림에 대한 임분구조 및 직경생장을 조사, 비교하였다. 조림 후 9년까지의 직경생장에 가래나무 임분기원간 통계적 유의차가 인정되었다. 천연림의 가래나무의 연평균직경성장량은 7.31mm/year로 최대값이었으며, 다음으로 맹아림에서는 6.93mm/year, 조림지 에서는 5.28mm/year로 최소값을 보였다. 조림한 가래나무의 초기의 직경생장이 맹아갱신된 나무나 천연생의 나무보다 지극히 낮다는 것은 가래나무 나근묘의 식재는 성적이 매우 불량함을 나타낸다고 판단된다. 이러한 결과로 볼 때, 가래나무림 갱신에서는 맹아, 천연하종, 직파조림 등의 다른 갱신법들도 적극 검토할 필요가 있다고 판단된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제45권1호
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• pp.34-42
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• 2019

Objectives: Various bone graft substitute materials are used to enhance bone regeneration in the maxillofacial skeleton. In the recent past, synthetic graft materials have been produced using various synthetic and natural calcium precursors. Very recently, eggshell-derived hydroxyapatite (EHA) has been evaluated as a synthetic bone graft substitute. To assess bone regeneration using EHA in cystic and/or apicectomy defects of the jaws through clinical and radiographic evaluations. Materials and Methods: A total of 20 patients were enrolled in the study protocol (CTRI/2014/12/005340) and were followed up at 4, 8, 12, and 24 weeks to assess the amount of osseous fill through digital radiographs/cone-beam computed tomography along with clinical parameters and complications. Wilcoxon matched pairs test, means, percentages and standard deviations were used for the statistical analysis. Results: The sizes of the lesions in the study ranged from 1 to 4 cm and involved one to four teeth. The study showed significant changes in the formation of bone, the merging of material and the surgical site margins from the first week to the first month in all patients (age range, 15-50 years) irrespective of the size of the lesions and the number of teeth involved. Bone formation was statistically significant from the fourth to the eighth week, and the trabecular pattern was observed by the end of 12 weeks with uneventful wound healing. Conclusion: EHA showed enhancement of bone regeneration, and healing was complete by the end of 12 weeks with a trabecular pattern in all patients irrespective of the size of the lesion involved. The study showed enhancement of bone regeneration in the early bone formative stage within 12 weeks after grafting. EHA is cost effective and production is environment friendly with no disease transfer risks. Thus, natural bioceramics will play an important role in the reduction of costs involved in grafting and reconstruction.

• 대한본초학회지
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• 제32권6호
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• pp.55-62
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• 2017

Objectives : This study aims to evaluate the effects of natural herb mixutre (NHM) on atopic dermatitis and skin regeneration using in vivo test. Methods : NHM was prepared with DW. 25% of NHM was applied to skin lesion, where atopic dermatitis was induced by DNCB in NC/Nga mice. The levels of cytokines (IL-4, IL-5, IL-6, IL-13, TNF-a, and $IFN-{\gamma}$), and IgE in serum were measured by Luminex. Immune cells (WBC, eosinophil, lymphocyte, and monocyte) in blood were counted by coulter counter. The gross investigation of atopic dermatitis index score test were performed during the NHM treatment period. Also, the histopathological change of dorsal skin was observed by H&E and M&T staining. Results : NHM showed the levels of IL-4, IL-5, IL-6, IL-13, IgE, WBC, eosinophil, lymphocyte, and monocyte in serum or blood were significantly decreased. On the contrary, the productions of FGF, and VEGF were increased in the serum. Also, atopic dermatitis index score in NHM-treated mice were observed in the similar levels to those of normal group. Histological examination demonstrated that NHM suppressed immune cell infiltration and thickening of epidermis, meanwhile the extraction induced collagen production in the dorsal skin. Conclusion : This study demonstrated that NHM is appeared to be effective on atopic dermatitis and skin regeneration efficacy based on the observations with hematologic, gross, and histologic examinations. Therefore, we suggest that NHM could be effectively used as an external therapeutics against atopic dermatitis and a consequence skin damage.

• Journal of Ecology and Environment
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• 제46권3호
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• pp.218-242
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• 2022

Background: Promising specific growth regulators are employed in the tissue cultures of various bamboo species. Specific natural hardening mixtures support the acclimatization and adaptation of bamboo under protected cultivation. Results: The growth regulators like 2, 4-Dichlorophenoxyacetic acid (2, 4-D), Naphthaleneacetic Acid (NAA), Thidiazuron (TDZ), 6-Benzylaminopurine (BAP), Kinetin, Gelrite, Benzyl Adenine (BA), Indole Butyric Acid (IBA), Coumarin, Putrescine, Gibberellic acid (GA₃), Indole Acetic Acid (IAA) has been widely used for callus induction, root regeneration and imposing plant regeneration in various species of bamboo such as Bambusa spp. and Dendrocalamus spp. Different combinations of growth regulators and phytohormones have been used for regenerating some of the major bamboo species. Natural hardening materials such as cocopeat, vermicompost, perlite, cow dung, farmyard manure, compost, soil, garden soil, and humus soil have been recommended for the acclimatization and adaptation of bamboo species. Standard combinations of growth regulators and hardening mixtures have imposed tissue culture, acclimatization, and adaptation in major bamboo species. Conclusions: Bamboo contributes to soil fertility improvement and stabilization of the environment. Bamboo species are also involved in managing the biogeochemical cycle and have immense potential for carbon sequestration and human use. This paper aims to review the various growth regulators, natural mixtures, and defined media involved in regenerating major bamboo species through in vitro propagation. In addition, the ecological benefits of safeguarding the environment are also briefly discussed.

• 한국가구학회지
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• 제27권3호
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• pp.246-252
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• 2016

From 2000s, modular construction has gained more attention due to many advantages such as reduction of duration, recycling. The modular structure is being used for urban regeneration recently. However, even though most facilities in the modular structures which are used as urban regeneration building are commercial spaces, exhibition spaces, eating and drinking spaces, there are lack of natural or mechanical ventilation systems. Also, there are relatively limited spaces on modular structure characteristic. Therefore, indoor environment performance of four buildings, which are performed as urban regeneration in Seoul, was evaluated by HCHO and $CO_2$ emissions. Consequently, the HCHO and $CO_2$ emissions of the commercial and exhibition spaces were confirmed that can influence on health of occupants. Therefore, the urban regeneration modular structure needs to add local ventilation systems for improvement of indoor air quality to more healthy and comfortable.