• Journal of Korean Society of Forest Science
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• v.112 no.1
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• pp.40-56
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• 2023

Tree species within the Populus genus grow rapidly and have an excellent capacity to absorb carbon, conferring substantial ability to effective purify the environment. Poplar breeding can be achieved rapidly and efficiently if a genetic linkage map is constructed and quantitative trait loci (QTLs) are identified. Here, a high-density genetic linkage map was constructed for the control pollinated progeny using the genotyping-by-sequencing (GBS) technique, which is a next-generation sequencing method. A search was also performed for the genes associated with quantitative traits located in the genetic linkage map by examining the variables of height and diameter at root collar, and resilience to insect damage. The height and diameter at root collar were measured directly, while the ability to recover from insect damage was scored in a 4-year-old breeding population of aspen hybrids (Odae19 × Bonghyeon4 F1) established in the research forest of Seoul National University. After DNA extraction, paternity was confirmed using five microsatellite markers, and only the individuals for which paternity was confirmed were used for the analysis. The DNA was cut using restriction enzymes and the obtained DNA fragments were prepared using a GBS library and sequenced. The analyzed results were sorted using Populus trichocarpa as a reference genome. Overall, 58,040 aligned single-nucleotide polymorphism (SNP) markers were identified, 17,755 of which were used for mapping genetic linkages. The genetic linkage map was divided into 19 linkage groups, with a total length of 2,129.54 cM. The analysis failed to identify any growth-related QTLs, but a gene assumed to be related to recovery from insect damage was identified on linkage group (chromosome) 4 through genome-wide association study.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.281-289
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• 2022

Fusarium head blight is an important disease of small grains. It is mainly caused by members of the Fusarium graminearum species complex (FGSC). Barley and wheat growers spray fungicides, especially demethylation-inhibitor fungicides, to suppress the disease. The objective of this study was to examine the changes in the sensitivity of the FGSC population to the triazole fungicide, propiconazole. A total of 124 and 350 isolates of FGSC were obtained from barley and wheat in Jeolla Province during 2010-2016 and 2020-2021, respectively. The species identity and trichothecene chemotypes of the FGSC isolates were determined based on polymerase chain reaction assays targeting translation elongation factor 1-alpha and TRI12 genes, respectively. Sensitivity to propiconazole was determined based on the effective concentration that reduced 50% of the mycelial growth (EC₅₀) using the agar dilution method. Of all isolates, F. asiaticum with the nivalenol chemotype was the most common (83.9% in 2010-2016 and 96.0% in 2020-2021), followed by F. asiaticum with the 3-acetyl deoxynivalenol chemotype (12.1% in 2010-2016 and 2.9% in 2020-2021). The EC₅₀ values of the isolates collected in 2010-2016 and 2020-2021 ranged from 0.0180 to 11.0166 ㎍/mL and 1.3104 to 17.9587 ㎍/mL, respectively. The mean EC₅₀ value of the isolates increased from 3.8648 ㎍/mL in 2010-2016 to 5.9635 ㎍/mL in 2020-2021. The baseline resistance to propiconazole was determined to be 7 ㎍/mL, based on the EC₅₀ value of isolates collected in 2010-2016, and the ratio of resistant isolates increased from 9.7% in 2010-2016 to 28.6% in 2020-2021.

• Korean Journal of Environmental Biology
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• v.40 no.1
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• pp.112-123
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• 2022

To assess the influence of environmental factors on the phytoplankton community structure and total phytoplankton biomass during four seasons in 2014, we investigated the abiotic and biotic factors at 25 stations in the Busan coastal region. The phytoplankton community and total phytoplankton biomass were strongly dependent on the discharge from the Nakdong River, and the high density of phytoplankton was related with the introduction of the Tsushima Warm Current (TWC), particularly in the thermohaline fronts of the fall season. The relationship between the salinity and nutrient (Dissolved inorganic nitrogen=DIN: R²=0.72, p<0.001 and Dissolved inorganic silicon=DSi: R²=0.78, p<0.001) highly correlated with the river discharge, implying that those nutrients have played a crucial role in the growth of diatom and cryptophyta. The total phytoplankton biomass was highest in the summer followed by autumn, spring, and winter. Diatom and cryptophyta species were dominant species during the four seasons. Additionally, there were strong positive correlations between Chlorophyll a and total phytoplankton biomass (R²=0.84, p<0.001), cryptophyta (R²=0.76, p<0.001) and diatom (R²=0.50, p<0.001), respectively. In particular, we found that there were significant differences in the nutrients, phytoplankton community compositions, and total phytoplankton biomass between the inner and the outer coastal region of Busan, depending on the amount of river discharge from the Nakdong River, particularly during rainy seasons. Therefore, the seasonal change of TWC and river discharge from the Nakdong River serve an important role in determining phytoplankton population dynamics in the Busan coastal region.

• Journal of the Korean Orthopaedic Association
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• v.54 no.1
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• pp.1-8
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• 2019

Globally, the elderly population is increasing rapidly, which means that the number of deformity correction operations for elderly spine deformity patient has increased. On the other hand, for aged patients with deformity correction operation, preoperative considerations to reduce the complications and predict a good clinical outcome are not completely understood. First, medical comorbidity needs to be evaluated preoperatively with the Cumulative Illness Rating Scale for Geriatrics or the Charlson Comorbidity Index scores. Medical comorbidities are associated with the postoperative complication rate. Managing these comorbidities preoperatively decreases the complications after a spine deformity correction operation. Second, bone densitometry need to be checked for osteoporosis. Many surgical techniques have been introduced to prevent the complications associated with posterior instrumentation for osteoporosis patients. The preoperative use of an osteogenesis inducing agent - teriparatide was also reported to reduce the complication rate. Third, total body sagittal alignment need to be considered. Many elderly spine deformity patients accompanied degenerative changes and deformities at their lower extremities. In addition, a compensation mechanism induces the deformed posture of the lower extremities. Recently, some authors introduced a parameter including total body sagittal alignment, which can predict the clinical outcome better than previous parameters limited to the spine or pelvis. As a result, total body sagittal alignment needs to be considered for elderly spine deformity patients after a deformity correction operation. In conclusion, for elderly spine deformity patients, medical comorbidities and osteoporosis need to be evaluated and managed preoperatively to reduce the complication rate. In addition, total body sagittal alignment needs to be considered, which is associated with better clinical outcomes than the previous parameters limited to the spine or pelvis.

• Journal of the Korean Orthopaedic Association
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• v.52 no.1
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• pp.1-6
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• 2017

Purpose: To retrospectively compare minimally invasive percutaneous plate osteosynthesis (MIPPO) with open plate fixation for the treatment of clavicle midshaft fracture. Materials and Methods: Between November 2011 to May 2014, 40 cases that were followed for more than 1 year-among all cases of MIPPO and open plate fixation-were analyzed. The study population was divided into two groups: group A included 20 cases of MIPPO and group B included 20 open plate fixation cases. The comparative analysis between the two groups was based on the operative time, bone union, functional evaluation (American Shoulder and Elbow Society score), incision length, pain relief (visual analogue scale, VAS), and complication. Results: The bone union was successful for all the cases, and the functional evaluation scores of the shoulder joint were satisfactory for both groups (p>0.05). The operative time was 47.5 minutes and 58.7 minutes for group A and B, respectively (p<0.05). The incision length for group A was 6.2 cm and that for group B was 10.7 cm with statistical significance (p<0.05). Pain relief (VAS) after surgery for group A showed a quick recuperation in the early stages. For complications, there were 2 cases of dysesthesia and 1 case of malunion due to metal fixation failure in group A. There were 6 cases of dysesthesia and 2 cases of cosmetic problem due to hypertrophic scar in group B. Conclusion: Surgical results of clavicle shaft fracture were satisfactory for both groups, but group A had advantages of shorter operative time, minimal incision length, and better pain relief in the early stages compared with group B. However, we need further evaluations with long-term follow-up results and complications, such as malunion and exposure on radiation.

• Korean Association of Arts Management
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• no.51
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• pp.35-73
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• 2019

The purpose of this study is to investigate the effects of culture and arts activities (experience, type, frequency) and participation motivation on subjective well-being and to investigate the mediating effects of learning motivation. For this study, the subject is limited to adults who are leading consumers of culture and art activities can decide what activity to do. By survey, data from 1,000 respondents are used for analysis after applying proportional sampling based on the proportion of sex and age indicated in the population statistics. Exploratory factor analysis and reliability analysis were conducted based on the collected data using SPSS v.22.0. The results obtained from the empirical analysis are as follows. First, regarding culture and art activities (experience, type, frequency) and subjective well-being, the results are as follows. H1. Those who experienced culture and arts activities have higher subjective well-being than non-experienced ones. H2. Participating in culture and art activity increases subjective well-being more than just spectating culture and art programs. H3. Heavy participants in culture and art activities have higher subjective well-being than lighter participants. These results indicate that culture and art activities are important variables that have a positive effect on subjective well-being. Therefore, participating in culture and art activities may be an appropriate way to enhance subjective well-being because they are life experiences that individuals can experience in their daily lives. Second, H4. internal motivation and external motivation, sub-factors of participation motivation in culture and art activities, have a positive effect on subjective well-being, and amotivation has a negative effect on subjective well-being. Therefore, in order to improve subjective well-being, it is important to strive to lower amotivation and increase internal and external motivation. Third, H5. learning motivation has a partial mediating effect on the relationship between participation motivation in culture and art activities and subjective well-being. This result suggests that culture and art activities and education might be helpful for subjective well-being when they are conducted together since participation motivation in culture.

• Korean Journal of Ecology and Environment
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• v.56 no.2
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• pp.172-186
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• 2023

Small ponds, which exhibit unstable succession pattern of plankton community, are less well studied than large lakes. Recently, the importance of small ponds for local biodiversity conservation has highlighted the necessity of understanding the dynamics of biological community. In the present study, we collected zooplankton from three small reservoirs with monthly basis and analyzed their seasonal dynamics. To understand the complicated zooplankton community dynamics of small reservoirs, we categorized zooplankton species into four groups (LALF Group, Low Abundance Low Frequency; LAHF Group, Low Abundance High Frequency; HALF Group, High Abundance Low Frequency; HAHF Group, High Abundance High Frequency) based on their occurrence pattern (abundance and frequency). We compared the seasonal pattern of each group, and estimated community diversity based on temporal beta diversity contribution of each group. The result revealed that there is a relationship between groups with the same abundance but different occurrence frequencies, and copepod nauplii are common important component for both abundance and frequency. On the other hand, species included with LALF Group throughout the study period are key in terms of monthly succession and diversity. LALF Group includes Anuraeopsis fissa, Hexarthra mira and Lecane luna. However, groups containing species that only occur at certain times of the year and dominate the waterbody, HALF Group, hindered to temporal diversity. The results of this study suggest that the species-specific occurrence pattern is one key trait of species determining its contribution to total annual biodiversity of given community.

• Korean Journal of Remote Sensing
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• v.39 no.2
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• pp.129-142
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• 2023

This study analyzed the ratio of carbon monoxide (CO) and carbon dioxide (CO₂), CO and nitrogen dioxide (NO₂) for cities and regionsin Korea and China using column-averaged carbon dioxide dry-air mole fraction (XCO₂) of the Orbiting Carbon Observatory-2/3, CO and NO₂ vertical column density (named XCO, XNO₂ in thisstudy) of TROPOspheric monitoring instrument from April 2018 to April 2022, and presented the relationship between socioeconomic indicators (population, number of vehicles, Gross Regional Domestic Product) and ratio, and differences in characteristics between Korea and China. First, CO₂ and CO were analyzed after calculating ΔXCO₂ and ΔXCO removing the background value and trend line due to the difference in atmospheric residence time of three gaseous substances (CO₂, CO, and NO₂). Comparing the three values by regions, ΔXCO and ΔXCO₂ were relatively higher in China and XNO₂ were higher in Korea and the ratio of both values (ΔXCO/ΔXCO₂, ΔXCO/XNO₂) was higher in China than in Korea. ΔXCO/ΔXCO₂, ΔXCO/XNO₂ and socioeconomic indicators have a positive correlation suggesting that the concentration of air pollutants and greenhouse gases is higher as the city is large and the economic activity is active. Regarding the differences in the ratio characteristics of Korea and China, the relationship between ΔXCO and ΔXCO₂ showed a negative correlation in Korea and a positive correlation in China. When the relationship between ΔXCO and XNO₂ was examined for summer and winter, the change of ΔXCO by season was not significant in Korea, whereasthe change of ΔXCO and XNO₂ by season waslarge in China resulting in the relationship between two countries appeared differently. These results suggest that seasonal variability and national emission characteristics should be considered in the process of analyzing the ratio of greenhouse gases to air pollutants.

• The Korean Journal of Zoology
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• v.14 no.2
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• pp.57-74
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• 1971

The present investigation has been done to observe the ecological habits of field mice to protect the rice from damages during the growing season in paddy-field and during the storge period. The results obtained are summarized as follows: 1. Of 155 mice captured in the period of April-November 1970, which belong to four genera (Apodemus, Cricetulus, Rattus, and Micromys), 148 mice(95%) were found as striped field mice (Apodemus agrarius coreae). The population density of striped field mouse was revealed by the present study as 55/ha, which is quite a low level compared with that in Japan of 900/ha. 2. The age distribution of the mice as judged by their body weight was found mainly composed of adult and the sex ratio was found to be 1.8 as determined with 147 individuals. The nest was found to be occupied by an adult and was composed of at least three openings and more than one food storage tunnels. The mice usually keep hulled rice rather than unhulled one in storage tunnel. The weight of food found in a nest was about 50 grams on an average. 3. The mice show a most active behaviour 1-2 hours after the sunset, around midnight, and an hour before the sunrise, but they are active even in daytime in order for searching for food and for breeding. 4. The ratio (%) of damage appeared in high stem of sweet corn in August was 30 ~ 40 percent, whereas that in low stem was 80 ~ 90 percent. The weight of spoiled grains in paddy-field was 11, 400gm/0.4ha and this gives an estimate of 349, 695 for whole country. 5. The female striped field mouse weighs average of about 30 grams and gives birth to average of 4.8 younglings which wean away from female mouse three weeks after delivery. 6. The natural enemies to the mice are found to be carnivores (weasel, cat, mountain cat, fox, raccoon, and otter), raptatores(eagle, owl, kete, buzzard), and snakes. Two kinds of field rats(Rattus norvegicus, Cricetulus tritor) are also the predator to the mice. 7. The feeding preference of striped field mice follows in decreasing order of sweet corn, soybean, sweet potatoes, chestnut, and wheat. The mice do not have a preference for barley, millet, rough millet, red bean, and green bean. 8. The starvation experiment, in which water alone was supplied, revealed that the mice in good physical and nutritional conditions survived for 71 ~ 79 hours, whereas those in worse conditions survived for only 32 ~ 39 hours.

• Journal of the Korean Association of African Studies
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• v.29
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• pp.27-53
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• 2009

At the start of the new century, South Africa probably had the largest number of HIV-infected people of any country in the world. The only nation that comes close is India with a population of one billion people compared to South Africa's figure of 57 million. The tragedy is that this did not have to happen. South Africa was aware of the dangers posed by AIDS as early as 1985. In 1991, the national survey of women attending antenatal clinics found that only 0.8percent were infected. In 1994, when the new government took power, the figure was still comparatively low at 7.6 %. The 2004 figure which has been published is 26.5%. This article tracks the epidemic globally, in the region and in South Africa. I explain some of the basic concepts around the disease and look at what may happen with respect to numbers. The situation is bad, and the number of people falling ill, dying and leaving families will rise over next few years. This will impact on South Africa in a number of important ways. This article assesses the demographic, economic and social consequences of the epidemic. It disposes of a number of myths and present the real facts. The AIDS in South Africa is not related to individuals only. It warns that AIDS in Africa is becoming a community and systemic problem. The acuteness of the problem does not stem merely from the fact that communities are affected, or could even be wipe out by the end of this decade, but from the fact that AIDS will place incredible burdens and obligations upon medical services, health care and religious communities such as churches. The facts confront churches' mission with the important question: who is going to take care of all the patients and where? The reality is that people dying of AIDS will have to be cared for at home by relatives and friends. A further question that arises is whether our people are prepared for this. AIDS was considered to be a homo-plague and the hunt was on for a scapegoat in the light of the fatal implication of the disease. At present we are in the strategic phase where we all realize that it will be of no avail to scare people with the ominous threat of AIDS AIDS destroys the optimism of our achievement ethics. This exposure of the culture of optimism is also an exposure of the so-called 'human basic fear which accuses Christianity that their concept of sin is a damper on man's search for liberation and basic need to be freed from all Imitation. AIDS is also a test for our ecclesiastical genuineness and the sincerity of our mission sensibility. It poses the question: How unconditional is Christian love? Is there room for the AIDS sufferer in the community of believers, despite the fact he is an acknowledged homosexual? The question to put to the church is whether the community of believers is an exclusive to put to the koinonia which excludes homosexuals. They may be welcome on principle, but in actual fact are not acceptable to the church community. As South Africa enters the new century, it is clear that the epidemic is not having a measurable impact. However, the impact of AIDS is gradual, subtle and incremental. The author's proposal of what is currently most needed in South Africa is that the little things will make a difference. It's about doing lots of little things better at grassroots level, with the emphasis on doing. There are so many community, churches and NGOs initiatives worth building on and intensifying. One must not underestimate the therapeutic value of working together in small groups to overcome a problem