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The Analysis of Forest Fire Fuel Structure Through the Development of Crown Fuel Vertical Distribution Model: A Case Study on Managed and Unmanaged Stands of Pinus densiflora in the Gyeongbuk Province (수관연료 수직분포모델 개발을 통한 산불연료구조 분석: 경북지역의 소나무림 산림시업지와 비시업지를 대상으로)

  • Lee, Sun Joo;Kwon, Chun Geun;Kim, Sung Yong
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.23 no.1
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    • pp.46-54
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    • 2021
  • This study compared and analyzed the effects of forest tending works on the vertical distribution of wildfire fuel loads on Pinus densiflora stands in Gyeongbuk province. The study sites were located in Youngju and Bonghwa in Pinus densiflora stands. A total of 10 sample trees were collected for the development of the crown fuel vertical distribution model. The 6th NFI (National Forest Inventory) selected a sample point that only extracted from managed and unmanaged stands of Pinus densiflora in the Gyeongbuk province. The fitness index (F.I.) of the two models developed was 0.984 to 0.989, with the estimated parameter showing statistical significance (P<0.05). A s a results, the vertical distribution of wildfire fuel loads range of unmanaged stands was from 1m to 11m with the largest distribution at point 5m at the tree height. On the other hand, the vertical distribution of wildfire fuel loads range of the managed stands was from 1m to 15m with the largest distribution at the point of 8m at the tree height. The canopy bulk density was 0.16kg/㎥ for the managed stands and 0.25kg/㎥ for the unmanaged stands, unmanaged stands were about 1.6 times more than managed stands. This result is expected to be available for simulation through the implementation of the 3D model as crown fuel was analyzed in three dimensions.

Status of Groundwater Potential Mapping Research Using GIS and Machine Learning (GIS와 기계학습을 이용한 지하수 가능성도 작성 연구 현황)

  • Lee, Saro;Fetemeh, Rezaie
    • Korean Journal of Remote Sensing
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    • v.36 no.6_1
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    • pp.1277-1290
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    • 2020
  • Water resources which is formed of surface and groundwater, are considered as one of the pivotal natural resources worldwide. Since last century, the rapid population growth as well as accelerated industrialization and explosive urbanization lead to boost demand for groundwater for domestic, industrial and agricultural use. In fact, better management of groundwater can play crucial role in sustainable development; therefore, determining accurate location of groundwater based groundwater potential mapping is indispensable. In recent years, integration of machine learning techniques, Geographical Information System (GIS) and Remote Sensing (RS) are popular and effective methods employed for groundwater potential mapping. For determining the status of the integrated approach, a systematic review of 94 directly relevant papers were carried out over the six previous years (2015-2020). According to the literature review, the number of studies published annually increased rapidly over time. The total study area spanned 15 countries, and 85.1% of studies focused on Iran, India, China, South Korea, and Iraq. 20 variables were found to be frequently involved in groundwater potential investigations, of which 9 factors are almost always present namely slope, lithology (geology), land use/land cover (LU/LC), drainage/river density, altitude (elevation), topographic wetness index (TWI), distance from river, rainfall, and aspect. The data integration was carried random forest, support vector machine and boost regression tree among the machine learning techniques. Our study shows that for optimal results, groundwater mapping must be used as a tool to complement field work, rather than a low-cost substitute. Consequently, more study should be conducted to enhance the generalization and precision of groundwater potential map.

Effect of Korean Medicine Treatment Including Korean Medicine Counselling on Weight Loss in Patients with Morbid Obesity: A Retrospective Chart Review (고도비만 환자 대상 한의 비만 상담을 포함한 한의치료의 체중 감량 효과: 후향적 차트 리뷰)

  • Kim, Sungha;Han, Kyungsun;Kwon, Ojin;Lee, Wongu;Yoon, Chulsang;Lee, Jun-Hwan
    • Journal of Korean Medicine for Obesity Research
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    • v.21 no.1
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    • pp.22-31
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    • 2021
  • Objectives: We conducted a retrospective chart review to investigate the effects of Korean Medicine (KM) treatment on weight loss in patients with morbid obesity (body mass index [BMI]≥30 kg/m2) and to compare the effects of KM counseling and non-counseling on weight loss. Methods: We performed a retrospective chart review of patients with morbid obesity who received KM treatment for at least 1 month. We evaluated the effects of KM treatment on body weight, BMI, body fat, fat mass, EuroQol-5D, and the Korean version of the obesity-related quality of life scale (KOQOL). We also assessed the liver and kidney functions, and adverse events. We performed a comparative analysis between the counseling and non-counseling groups. Results: A total of 37 patients who underwent 4 weeks of KM treatment involving Wolbi-tang, electroacupuncture, and KM counseling were included in this study. Twenty-one patients were assigned to the counseling group and sixteen patients to the non-counseling group. There was a significant decrease in weight, BMI, fat mass, and KOQOL (P<0.05) with improvements in total cholesterol, low-density lipoprotein, and triglycerides. The counseling group had a greater reduction in body weight, BMI, body fat, and fat mass compared to the non-counseling group, although it was not significant. In the BMI below 35 (n=25), the reduction ratio of body weight, body fat mass, and body fat was higher in the counseling group than in the non-counseling group; additionally, body fat decreased significantly in counseling group (P<0.05). No severe adverse effects were observed. Conclusion: KM treatment could be effective for weight loss, especially in patients with morbid obesity, KM counseling could also be a good tool for weight loss, typically in patients with BMI<35 kg/m2.

The Effect of Hounsfield Unit Value with Conventional Computed Tomography and Intraoperative Distraction on Postoperative Intervertebral Height Reduction in Patients Following Stand-Alone Anterior Cervical Discectomy and Fusion

  • Lee, Jun Seok;Son, Dong Wuk;Lee, Su Hun;Ki, Sung Soon;Lee, Sang Weon;Song, Geun Sung;Woo, Joon Bum;Kim, Young Ha
    • Journal of Korean Neurosurgical Society
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    • v.65 no.1
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    • pp.96-106
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    • 2022
  • Objective : The most common complication of anterior cervical discectomy and fusion (ACDF) is cage subsidence and maintenance of disc height affects postoperative clinical outcomes. We considered cage subsidence as an inappropriate indicator for evaluating preservation of disc height. Thus, this study aimed to consider patients with complications such as reduced total disc height compared to that before surgery and evaluate the relevance of several factors before ACDF. Methods : We retrospectively reviewed the medical records of 40 patients who underwent stand-alone single-level ACDF using a polyetheretherketone (PEEK) cage at our institution between January 2012 and December 2018. Our study population comprised 19 male and 21 female patients aged 24-70 years. The minimum follow-up period was 1 year. Twenty-seven patients had preoperative bone mineral density (BMD) data on dual-energy X-ray absorptiometry. Clinical parameters included sex, age, body mass index, smoking history, and prior medical history. Radiologic parameters included the C2-7 cobb angle, segmental angle, sagittal vertical axis, disc height, and total intervertebral height (TIH) at the preoperative and postoperative periods. Cage decrement was defined as the reduction in TIH at the 6-month follow-up compared to preoperative TIH. To evaluate the bone quality, Hounsfield unit (HU) value was calculated in the axial and sagittal images of conventional computed tomography. Results : Lumbar BMD values and cervical HU values were significantly correlated (r=0.733, p<0.001). We divided the patients into two groups based on cage decrement, and 47.5% of the total patients were regarded as cage decrement. There were statistically significant differences in the parameters of measuring the HU value of the vertebra and intraoperative distraction between the two groups. Using these identified factors, we performed a receiver operating characteristic (ROC) curve analysis. Based on the ROC curve, the cut-off point was 530 at the HU value of the upper cortical and cancellous vertebrae (p=0.014; area under the curve [AUC], 0.727; sensitivity, 94.7%; specificity, 42.9%) and 22.41 at intraoperative distraction (p=0.017; AUC, 0.722; sensitivity, 85.7%; specificity, 57.9%). Using this value, we converted these parameters into a bifurcated variable and assessed the multinomial regression analysis to evaluate the risk factors for cage decrement in ACDF. Intraoperative distraction and HU value of the upper vertebral body were independent factors of postoperative subsidence. Conclusion : Insufficient intraoperative distraction and low HU value showed a strong relationship with postoperative intervertebral height reduction following single stand-alone PEEK cage ACDF.

The Effects of Oral Administration of Deer Antler Extracts on an Osteoporosis-induced Animal Model: A Systematic Review and Meta-analysis (골다공증 유발 동물모델에서 녹용 추출물의 경구 투여 효과: 체계적 문헌고찰 및 메타분석)

  • Lee, Jung Min;Kim, Nam Hoon;Lee, Eun-Jung
    • Journal of Korean Medicine Rehabilitation
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    • v.32 no.2
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    • pp.65-81
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    • 2022
  • Objectives This study aimed to assess the effects of oral administration of deer antler extracts on an osteoporosis-induced animal model. We analyzed the results of using deer antler single extracts on animal models with osteoporosis through a systematic review and meta-analysis. Methods We included osteoporosis studies in animal experiments that administrated deer antler extracts orally. We searched the following 13 databases without a language restriction: PubMed, EMBASE, Cochrane Library, Cumulative Index to Nursing and Allied Health Literature (CINAHL), China National Knowledge Infrastructure (CNKI), Wanfang, Korean Medical Database (KMbase), National Digital Science Library (NDSL), Korean Traditional Knowledge (Koreantk), Oriental Medicine Advanced Searching Integrated System (OASIS), Research Information Sharing Service (RISS), Korea Institute of Science and Technology Information (KISTI), and Koreanstudies Information Service System (KISS). We used Systematic Review Centre for Laboratory Animal Experimentation's risk of bias tool for assessing the methodological quality of the included studies. Results A total of 299 potentially relevant studies were searched and 11 were included for a systematic review. Nine studies used a single deer antler extract. A study compared the effects of single extracts of deer antler and antler glue, while another study compared the effects of three single extracts of deer antler, old antler, and antler glue. For evaluating the intervention effect, bone mineral density (BMD) was measured as the primary outcome, while the histomorphometric indicators of the bone and serum alkaline phosphatase and osteocalcin levels were used as the secondary outcome variables. On conducting a meta-analysis of studies on single deer antler extract, BMD was observed to be significantly increased compared to that in control group (standardized mean difference [SMD]=2.11; 95% confidence interval [CI]=1.58~2.65; Z=7.75; p<0.00001; I2=56%). As a result of meta-analysis, according to the concentration of deer antler, the group with high concentration showed statistically significantly higher BMD than the group with low concentration (SMD=1.28; 95% CI=0.74~1.82; Z=4.63; p<0.00001; I2=9%). Conclusions The research shows that the deer antler extracts have significant anti-osteoporotic effects on the osteoporosis-induced animal model. However the studies included in this research had a high methodological risk of bias. This indicates the requirement of considerable attention in the interpretation of the study results.

Comparative Analysis of ABM/P-15, Bone Morphogenic Protein and Demineralized Bone Matrix after Instrumented Lumbar Interbody Fusion

  • Sathe, Ashwin;Lee, Sang-Ho;Kim, Shin-Jae;Eun, Sang Soo;Choi, Yong Soo;Lee, Shih-min;Seuk, Ju-Wan;Lee, Yoon Sun;Shin, Sang-Ha;Bae, Junseok
    • Journal of Korean Neurosurgical Society
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    • v.65 no.6
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    • pp.825-833
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    • 2022
  • Objective : ABM/P-15 (anorganic bone matrix/15-amino acid peptide fragment) is a commercially available synthetically manufactured P-15 collagen peptide fragment, that is adsorbed on ABM. This study was done to investigate the efficacy of ABM/P-15 in achieving fusion in the lumbar spine and comparing it with that of recombinant bone morphogenic protein-2 (rhBMP-2) and demineralized bone matrix (DBM). Methods : A retrospective observational study of prospectively collected data of 140 patients who underwent lumbar spinal fusion surgeries in a single specialty spine hospital between 2016 and 2020, with a minimum 6-month follow-up was conducted. Based on the material used for the augmentation of the bone graft at the fusion site, the patients were divided into three categories namely ABM/P-15, rhBMP-2, and DBM group. Results : ABM/P-15, rhBMP-2, and DBM were used in 46, 44, and 50 patients, respectively. Patient characteristics like age, gender, bone mineral density, smoking history, and presence of diabetes mellitus were comparable amongst the three groups. Average follow-up was 16.0±5.2, 17.9±9.8, and 26.2±14.9 months, respectively in ABM/P-15, rhBMP-2, and DBM groups. The fusion was achieved in 97.9%, 93.2%, and 98% patients while the average time-to-union was 4.05±2.01, 10±4.28, and 9.44±3.49 months (p<0.001), respectively for ABM/P-15, rhBMP-2, and DBM groups. The average pre-operative Visual analogue scale score was 6.93±2.42, 7.14±1.97, 7.01±2.14 (p=0.900) for ABM/P-15, rhBMP-2 and DBM groups, respectively, which reduced to 1.02±0.80, 1.21±0.96, and 0.54±0.70 (p=0.112), respectively at the last follow up. Pre-operative Oswestry disability index scores were 52.7±18.02, 55.4±16.8, and 53.56±19.6 (p=0.751) in ABM/P-15, rhBMP-2, and DBM groups, which post-operatively reduced to 33.77±15.52, 39.42±16.47, and 38.3±15.89 (p=0.412) and further to 15.74±8.3, 17.41±10.45, and 16.76±9.81 (p=0.603), respectively at the last follow-up. Conclusion : ABM/P-15 appears to achieve union significantly earlier than rhBMP-2 and DBM in lumbar spinal fusion cases while maintaining a comparable clinical and complication profile.

Analysis of calcium fluoride single crystal grown by the czochralski method (초크랄스키 방법으로 성장한 CaF2 단결정 분석)

  • Lee, Ha-Lin;Na, Jun-Hyuck;Park, Mi-Seon;Jang, Yeon-Suk;Jung, Hea-Kyun;Kim, Doo-Gun;Lee, Won-Jae
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.32 no.6
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    • pp.219-224
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    • 2022
  • CaF2 single crystal has a large band gap (12 eV), and it is used for optical windows, prisms, and lenses due to its excellent transmittance in a wide wavelength range and low refractive index. Moreover, it is expected to be one of the materials for ultraviolet transmissive laser optical components. CaF2 belongs to the fluoride compounds and has a face-centered cubic (FCC) structure with three sub-lattices. The representative method for CaF2 single crystal growth is Czochralski, which method has the advantages of high production efficiency and the ability to make large crystals. In this study, X-ray diffraction (XRD), X-ray rocking curves (XRC) measurement, and chemical etching were performed to analyze the crystallinity and defect density of the CaF2 single crystals, grown by the Czochralski method. Fourier-transform infrared spectroscopy (FT-IR) and UV-VIS-NIR spectroscopy systems were used to investigate the optical properties of the CaF2 crystal. The provability of various applications, including UV application, was systematically investigated with various analysis results.

A Study on the Combustion Characteristics of the Crown of Pine Trees in the Drying Season (건조기 소나무 수관부 부위별 연소특성에 관한 연구)

  • Hyuk Kwon;Jong Ho Lee
    • Journal of the Korean Society of Safety
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    • v.38 no.4
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    • pp.39-46
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    • 2023
  • Pine trees, which account for 23% of the forested area of the Republic of Korea, are highly vulnerable to fire in comparison to broad-leaved trees due to the presence of consistent water tube sections throughout the year and resin that is composed of approximately 20% oil. In addition, the pattern of forest fires is determined by weather, topographic conditions, and fluctuation in moisture content. Therefore, when fire breaks out in pine tree forests during the dry season (January to March), it is difficult to extinguish, and it quickly spreads. In this study, the combustion characteristics of pine needles, pine cones, and pine branches in the water tube sections of living pine trees were compared and analyzed in accordance with the moisture content as per the ISO 5660-1. The monthly moisture content was analyzed from January to March, and it was found to be the lowest in March, with 53.6% for pine needles, 51.9% for pine branches, and 10.9% for pine cones. In particular, pine cones were more vulnerable to fire as compared to pine needles and pine branches because their moisture content was more than five times lower than that of pine needles and branches. The ignition time, which affects the speed of flame propagation, was the most rapid in March, and the fastest ignition time was for pine cones, at 19 seconds, followed by 34 seconds for pine needles, and 256 seconds for pine branches. The pine branches were the last to be ignited due to the effect of density, according to the thickness and specific gravity of the specimen. The peak heat release rate, which is a measurable index of fire intensity, was analyzed for pine cones and found to be 184.28 kW/m2 , while the mean effective heat of combustion was 19.79 MJ/kg, and the total heat release rate was 39.7 MJ/m2 , and these values were higher than those of pine branches and pine needles. Thus, we determined that the flame propagation speed and fire intensity according to the moisture content can be used to evaluate the risk of fire to the water tube section of pine trees. It is suggested that because of the combustion characteristics of the pine cone in March, that is when the forest is most vulnerable to fires.

Reparative, Neuroprotective and Anti-neurodegenerative Effects of Granulocyte Colony Stimulating Factor in Radiation-Induced Brain Injury Model

  • Gokhan Gurkan;Ozum Atasoy;Nilsu Cini;Ibrahim Halil Sever;Bahattin Ozkul;Gokhan Yaprak;Cansin Sirin;Yigit Uyanikgil;Ceren Kizmazoglu;Mumin Alper Erdogan;Oytun Erbas
    • Journal of Korean Neurosurgical Society
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    • v.66 no.5
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    • pp.511-524
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    • 2023
  • Objective : This animal model aimed to compare the rat group that received brain irradiation and did not receive additional treatment (only saline) and the rat group that underwent brain irradiation and received Granulocyte colony stimulating factor (G-CSF) treatment. In addition, the effects of G-CSF on brain functions were examined by magnetic resonance (MR) imaging and histopathologically. Methods : This study used 24 female Wistar albino rats. Drug administration (saline or G-CSF) was started at the beginning of the study and continued for 15 days after whole-brain radiotherapy (WBRT). WBRT was given on day 7 of the start of the study. At the end of 15 days, the behavioral tests, including the three-chamber sociability test, open field test, and passive avoidance learning test, were done. After the behavioral test, the animals performed the MR spectroscopy procedure. At the end of the study, cervical dislocation was applied to all animals. Results : G-CSF treatment positively affected the results of the three-chamber sociability test, open-space test and passive avoidance learning test, cornu Ammonis (CA) 1, CA3, and Purkinje neuron counts, and the brain levels of brain-derived neurotrophic factor and postsynaptic density protein-95. However, G-CSF treatment reduced the glial fibrillary acidic protein immunostaining index and brain levels of malondialdehyde, tumor necrosis factor-alpha, nuclear factor kappa-B, and lactate. In addition, on MR spectroscopy, G-CSF had a reversible effect on brain lactate levels. Conclusion : In this first designed brain irradiation animal model, which evaluated G-CSF effects, we observed that G-CSF had reparative, neuroprotective and anti-neurodegenerative effects and had increased neurotrophic factor expression, neuronal counts, and morphology changes. In addition, G-CSF had a proven lactate-lowering effect in MR spectroscopy and brain materials.

Consistency of 1-day and 3-day average dietary intake and the relationship of dietary intake with blood glucose, hbA1c, BMI, and lipids in patients with type 2 diabetes (제2형 당뇨병 환자의 1일과 3일 평균 식이섭취량의 일관성과 혈당, 당화혈색소, 체질량지수, 지질과의 관련성)

  • DaeEun, Lee;Haejung, Lee;Sangeun, Lee; MinJin, Lee;Ah Reum, Khang
    • Journal of Korean Biological Nursing Science
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    • v.25 no.1
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    • pp.20-31
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    • 2023
  • Purpose: This study aimed to determine the consistency of 1-day and 3-day average dietary intake using the 24-hour diet recall method and to investigate the relationship of diet intake with physiological indicators potentially associated with diabetic complications in patients with diabetes. Methods: This study conducted a secondary data analysis using pretest data of a nursing intervention study entitled "Development of deep learning based AI coaching program for diabetic patients with high risk and examination of its effects." Data were analyzed through descriptive analysis, one-way repeated-measures analysis of variance, and Pearson correlation coefficients using SPSS 26.0. Results: The average total daily calorie intake over 3 days was 1,494.48 ± 436.47 kcal/day: 1,510.90 ± 547.76 kcal/day on the first day, 1,414.22 ± 527.58 kcal/day on the second day, 1,558.34 ± 645.83 kcal/ day on the third day, showing significant differences (F = 3.59, p = .031). The correlation coefficient between the 1-day and 3-day average dietary intake was 0.41-0.77 for each nutrient and 0.62-0.80 for each food group. Vegetable intake showed negative correlations with body mass index (BMI; r = -.19, p = .023) and triglycerides (r = -.18, p = .036), whereas dairy intake was positively associated with low-density lipoprotein-cholesterol (LDL; r = -0.18, p = .034) and triglycerides (r = .40, p<.001). Conclusion: This study demonstrated that 1-day dietary intake was highly correlated with 3-day average dietary intake using the 24-hour diet recall method. Food groups showed significant associations with physiological indicators of potential diabetic complications such as BMI, triglycerides, and LDL levels. Further studies are needed to improve the knowledge base on the relationships between physiological indicators and food groups.