SHRIMP allanite U-Th-Pb dating of bimodal Triassic metamorphism of Neoarchean tonalitic gneisses, Daeijak Island, central Korea

The microstructures, compositions and U-Th-Pb ages of allanite from tonalitic gneisses in a Neoarchean migmatite complex, Daeijak Island, central Korea, have been investigated. Allanite crystals up to ∼300 μm in diameter occur with accessory apatite,

Estimation of the Virtual Water Content of Main Crops on the Korean Peninsula Using Multiple Regional Climate Models and Evapotranspiration Methods

Sustainable agriculture in the era of climate change needs to find solutions for the retention and proper utilization of water. This study proposes an ensemble approach for identifying the virtual water content (VWC) of main crops on the Korean Peninsula in past and future climates. Ensemble results with low uncertainty were obtained using three regional climate models, five potential evapotranspiration methods, and the Environmental Policy Integrated Climate (EPIC) crop model. The productivity results of major crops (rice and maize) under climate change are likely to increase more than in the past based on the ensemble results. The ensemble VWC is calculated using three types of crop yields and fifteen consumptive amounts of water use in the past and the future. While the ensemble VWC of rice and maize was 1.18 m^3 kg^-1 and 0.58 m^3 kg^-1, respectively, in the past, the future amounts were estimated at 0.76 m^3 kg^-1 and 0.48 m3 kg^-1, respectively. The yields of both crops showed a decline in future projections, indicating that this change could have a positive impact on future water demand. The positive changes in crop productivity and water consumption due to climate change suggest that adaptation to climate change can be an opportunity for enhancing sustainability as well as for minimizing agricultural damage

Spatialization and Prediction of Seasonal NO2 Pollution Due to Climate Change in the Korean Capital Area through Land Use Regression Modeling

Urbanization is causing an increase in air pollution leading to serious health issues. However, even though the necessity of its regulation is acknowledged, there are relatively few monitoring sites in the capital metropolitan city of the Republic of Korea. Furthermore, a significant relationship between air pollution and climate variables is expected, thus the prediction of air pollution under climate change should be carefully attended. This study aims to predict and spatialize present and future NO2 distribution by using existing monitoring sites to overcome deficiency in monitoring. Prediction was conducted through seasonal Land use regression modeling using variables correlated with NO2 concentration. Variables were selected through two correlation analyses and future pollution was predicted under HadGEM-AO RCP scenarios 4.5 and 8.5. Our results showed a relatively high NO2 concentration in winter in both present and future predictions, resulting from elevated use of fossil fuels in boilers, and also showed increments of NO2 pollution due to climate change. The results of this study could strengthen existing air pollution management strategies and mitigation measures for planning concerning future climate change, supporting proper management and control of air pollution

Assessing Climate Change Impact on Forest Habitat Suitability and Diversity in the Korean Peninsula

Habitat changes in temperate forests are more vulnerable to climate change than tropical or boreal forests. This study assessed forest habitat suitability and diversity to determine the impact of climate change on the Korean Peninsula. We used the MaxEnt (Maximum Entropy) species distribution model, three key climate indices, and two representative climate change scenarios, using short and long-term data. Two of the three key climate indices related to temperature were more capricious than the precipitation-related index in the future. In the baseline prediction, both statistical and qualitative validation using the actual vegetation map showed excellent results. Regarding forest habitat suitability, northward migration and substantial increase were definitely distinctive in warm temperate evergreen forest. On the other hand, subalpine forest areas decreased significantly due to climate change; the suitable area for Representative Concentration Pathways (RCP) 8.5 2070s decreased by more than half. With regard to forest habitat diversity, regions with high diversity declined due to climate change. In the RCP 8.5 scenario, areas where all three forest types are suitable no longer appeared; however, in the case of RCP 4.5 2050s, suitable areas for two forest types increased, which implies climate change is not only negative in terms of diversity. As this negative prediction of future change is discouraging, active mitigation and adaptation are required to prevent these changes. The sustainability of future ecosystems is still dependent on our efforts

Multi-Model Approaches to the Spatialization of Tree Vitality Surveys: Constructing a National Tree Vitality Map

It is essential to maintain the health of forests so that they are protected against a diverse range of stressors and show improved resilience. An area-based forest health map is required for efficient forest management on a national scale however, most national forest inventories are based on in-situ observations. This study examined methodologies to establish an area-based map on tree vitality grade using field survey data, particularly that containing information on several trees at one point. The forest health monitoring dataset of the Republic of Korea was used in combination with 37 satellite-based environmental predictors. Four methods were considered: Multinomial logistic regression (MLR), random forest classification (RF), indicator kriging (IK), and multi-model ensemble (MME) approaches using species distribution models. The MLR and RF produced biased results, whereby almost all regions were classified as first grade; the spatialization results of these methods were considered inappropriate for forest management. The maps produced using the IK and MME methods improved the distinctions between the distributions of five grades compared to the previous two methodologies however, the MME method produced better results, reliably reflecting topographical and climatic characteristics. Comparisons with the vegetation condition index and bioclimate vulnerability index also emphasized the usefulness of the MME. This study is particularly relevant to the national forest managers who struggle to find the most effective forest monitoring and management strategies. Suggestions to improve spatialization of field survey data are further discussed

Estimation of the Virtual Water Content of Main Crops on the Korean Peninsula Using Multiple Regional Climate Models and Evapotranspiration Methods

Sustainable agriculture in the era of climate change needs to find solutions for the retention and proper utilization of water. This study proposes an ensemble approach for identifying the virtual water content (VWC) of main crops on the Korean Peninsula in past and future climates. Ensemble results with low uncertainty were obtained using three regional climate models, five potential evapotranspiration methods, and the Environmental Policy Integrated Climate (EPIC) crop model. The productivity results of major crops (rice and maize) under climate change are likely to increase more than in the past based on the ensemble results. The ensemble VWC is calculated using three types of crop yields and fifteen consumptive amounts of water use in the past and the future. While the ensemble VWC of rice and maize was 1.18 m3 kg−1 and 0.58 m3 kg−1, respectively, in the past, the future amounts were estimated at 0.76 m3 kg−1 and 0.48 m3 kg−1, respectively. The yields of both crops showed a decline in future projections, indicating that this change could have a positive impact on future water demand. The positive changes in crop productivity and water consumption due to climate change suggest that adaptation to climate change can be an opportunity for enhancing sustainability as well as for minimizing agricultural damage

Swedish amyloid precursor protein mutation increases cell cycle-related proteins in vitro and in vivo

Reactivation of the cell cycle, including DNA replication, might play a major role in Alzheimer's disease. In this study, we report that the expressions of Swedish double mutation of amyloid precursor protein (Swe-APP) or of the APP intracellular domain (AICD) into nerve growth factor (NGF)-differentiated PC12 cells or rat primary cortical neurons increased mRNA and protein levels of cyclin D1 and cyclin B1. Treatment with lithium chloride (a glycogen synthase kinase-3beta inhibitor) down-regulated cyclin B1 induced by Swe-APP expression but up-regulated cyclin D1 expression induced by Swe-APP, suggesting that glycogen synthase kinase-3beta activity is involved in these expression changes of cyclins D1 and B1. Swe-APP, which is a prevailing cause of familial Alzheimer's disease, is well known to increase amyloid beta peptide production both in vitro and in vivo, but the underlying molecular means whereby it leads to the pathogenesis of AD remains unknown. The finding that cyclin D1 and B1 expressions were up-regulated by Swe-APP in in vitro cultured cells was substantiated in the brain tissues of Tg2576 mice, which harbor the Swe-APP mutation. These results suggest that some disturbances in cell cycle regulation may be involved in Swe-APP or AICD-induced neurodegeneration and that these contribute to the pathogenesis of AD

Swedish amyloid precursor protein mutation increases phosphorylation of eIF2alpha in vitro and in vivo

Swedish double mutation (KM670/671NL) of amyloid precursor protein (Swe-APP), a prevailing cause of familial Alzheimer's disease (FAD), is known to increase in Abeta production both in vitro and in vivo, but its underlying molecular basis leading to Alzheimer's disease (AD) pathogenesis remains to be elucidated, especially for the early phase of disease. We have confirmed initially that the expression of Swe-APP mutant transgene reduced cell viability via ROS production but this effect was eliminated by an anti-oxidative agent, vitamin E. We also found that eukaryotic translation initiation factor-2alpha (eIF2alpha), which facilitates binding of initiator tRNA to ribosomes to set on protein synthesis, was phosphorylated in cultured cells expressing Swe-APP. This increase in phosphorylated eIF2alpha was also attenuated significantly by treatment with vitamin E. The finding that eIF2alpha became highly phosphorylated by increased production of Abeta was substantiated in brain tissues of both an AD animal model and AD patients. Although an increase in Abeta production would result in cell death eventually (in late-phase of the disease), the altered phosphorylation state of eIF2alpha evoked by Abeta may account for the decreased efficacy of mRNA translation and de novo protein synthesis required for synaptic plasticity, and may consequently be one of molecular causes for impairment of cognitive functions exhibited in the early phase of AD patients

Development of a Methodology for the Conservation of Northern-Region Plant Resources under Climate Change

According to the guidelines of the Nagoya Protocol, species are now recognized as ‘resources’ and owned by each country, thereby emphasizing the significance of biological resources and the importance of the continuous efforts made to systematically manage them. Despite these efforts, climate change, which influences climatic factors such as temperature and precipitation, is expected to negatively impact the struggle for conservation of biological resources by affecting species’ habitats. We aimed to devise methodologies that could be utilized for the management of biological resources, especially valuable tree species, that are experiencing difficulties due to climate change. First, changes in habitat of the northern-region plant Needle fir (Abies holophylla) due to of climate change were estimated using the BIOMOD2 package in R under the RCP8.5 scenario. Second, the time period of management was estimated based on the change in habitat area over time. It is expected that 30% of the current habitat of A. holophylla will be lost by 2030 and 50% will be lost by 2042. Third, four management zones (maintenance, reduction, dispersal, and non-habitat areas) were derived by comparing habitats according to the period of management required. In this case, we compared the present and the time point at which 30% habitat loss (2030) is expected to occur. After that, the management steps that can be taken for each management zone were suggested. Our results show the impact of climate change, especially change in Bio1 (annual mean temperature) and Bio13 (precipitation of wettest month), on species distribution patterns and have potential applicability in biological resource management. We have specified the suitable point of time, area, and direction of management in this study, which will contribute to climate change management planning and policy-making. By doing so, we hope that when a management policy on biological resources is applied, by dividing the four management zones, policymakers will be able to apply a cost-efficient policy

Mefenamic acid shows neuroprotective effects and improves cognitive impairment in in vitro and in vivo Alzheimer's disease models

Nonsteroidal anti-inflammatory drugs (NSAIDs) exert anti-inflammatory, analgesic, and antipyretic activities and suppress prostaglandin synthesis by inhibiting cyclooxygenase, an enzyme that catalyzes the formation of prostaglandin precursors from arachidonic acid. Epidemiological observations indicate that the long-term treatment of patients suffering from rheumatoid arthritis with NSAIDs results in reduced risk and delayed onset of Alzheimer's disease. In this study, we investigated the therapeutic potential for Alzheimer's disease of mefenamic acid, a commonly used NSAID that is a cyclooxygenase-1 and 2 inhibitor with only moderate anti-inflammatory properties. We found that mefenamic acid attenuates the neurotoxicities induced by amyloid beta peptide (Abeta)(1-42) treatment and the expression of a Swedish double mutation (KM595/596NL) of amyloid precursor protein (Swe-APP) or the C-terminal fragments of APP (APP-CTs) in neuronal cells. We also show that mefenamic acid decreases the production of the free radical nitric oxide and reduces cytochrome c release from mitochondria induced by Abeta(1-42), Swe-APP, or APP-CTs in neuronal cells. In addition, mefenamic acid up-regulates expression of the antiapoptotic protein Bcl-X(L). Moreover, our study demonstrates for the first time that mefenamic acid improves learning and memory impairment in an Abeta(1-42)-infused Alzheimer's disease rat model. Taking these in vitro and in vivo results together, our study suggests that mefenamic acid could be used as a therapeutic agent in Alzheimer's disease