• Geomechanics and Engineering
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• v.37 no.4
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• pp.419-429
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• 2024

The primary goal was to assess how the addition of cement dust, a byproduct known to be harmful, could be used to stabilize clay. Various percentages of cement dust were added to soil samples, which were then subjected to triaxial testing at different rates of strain using an unconsolidated undrained triaxial machine. Six different rates of strain were applied to analyze the response of the clay under different conditions, resulting in 216 triaxial sample tests. As the percentage of cement dust in the clay samples increased, there was a noticeable increase in the strength properties of the clay, indicating a positive effect of cement dust on the clay's strength characteristics. Higher rates of strain during testing led to increased strength properties of the clay. Varying cement dust content influenced the impact of increasing the rate of strain on the clay's strength properties. Higher cement dust content reduced the sensitivity of the clay to changes in strain rate, indicating that the clay became less responsive to changes in strain rate as cement dust content increased. Potential for Clay Stabilization Cement dust proved the potential to enhance the strength properties of clay, indicating its potential utility in clay stabilization applications. Both higher percentages of cement dust and higher rates of strain were found to increase the clay's strength. It's essential to consider both the percentage of cement dust and the rate of strain when assessing the strength properties of clay in practical applications.

• Journal of Korean Society of Forest Science
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• v.97 no.4
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• pp.437-444
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• 2008

This study has intended to evaluate the forest recreation functions to seek methods to designate the recreational areas inside a recreation forest. This study has Mt. Chung-ok in Korea as a study area to which Quantification method II as a valuation measure was applied. This study also has chosen a degree of recreational utility as an external criterion and six factors including Forest type, Forest age, Slope, Riparian area, Road, and Facility for the 173 stands in this area. As a result, absolute discriminated success rate was obtained, so that the first and second estimated correlation ratios were 82% and 74%, respectively. Road and Slope had great influences on the potential power of recreational functions. In the category, recreational function was more influenced by the existence of road and the lower degree of slope. Also, this study has drawn an evaluation map, which displayed the potential power of recreational functions by classifying three discrimination points such as H(High), M(Medium), and L(Low) through calculating the degree of recreational utility of the recreation forest for the stands by applying an estimation formula of recreational function in the stands. This study seems to be worthwhile in terms of actual, experimental, and intuitive interpretation for the degree of recreational utility calculated by using Quantification method theory.

• The Korean Journal of Applied Statistics
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• v.32 no.2
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• pp.173-185
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• 2019

Causal questions are prevalent in scientific research, for example, how effective a treatment was for preventing an infectious disease, how much a policy increased utility, or which advertisement would give the highest click rate for a given customer. Causal inference theory in statistics interprets those questions as inferring the effect of a given intervention (treatment or policy) in the data generating process. Causal inference has been used in medicine, public health, and economics; in addition, it has received recent attention as a tool for data-driven decision making processes. Many recent datasets are observational, rather than experimental, which makes the causal inference theory more complex. This review introduces key concepts and recent trends of statistical causal inference in observational studies. We first introduce the Neyman-Rubin's potential outcome framework to formularize from causal questions to average treatment effects as well as discuss popular methods to estimate treatment effects such as propensity score approaches and regression approaches. For recent trends, we briefly discuss (1) conditional (heterogeneous) treatment effects and machine learning-based approaches, (2) curse of dimensionality on the estimation of treatment effect and its remedies, and (3) Pearl's structural causal model to deal with more complex causal relationships and its connection to the Neyman-Rubin's potential outcome model.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.21 no.2
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• pp.93-100
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• 2018

Purpose: Rome criteria are considered the gold standard for diagnosing functional constipation. The modified Bristol stool form scale (m-BSFS) was validated to measure stool form in children. However, neither the potential use of the m-BSFS as a tool to facilitate the diagnosis of potential constipation, nor the agreement between m-BSFS and stool consistency by Rome has been studied. Our objective is to determine if m-BSFS is a reliable tool to facilitate detection of constipation; and the agreement between stool form by m-BSFS and hard stool criteria in Rome. Methods: A survey tool with the Rome III criteria and the m-BSFS was developed. A Likert-scale addressed frequency of each stool form on the m-BSFS. Responses to Rome III and m-BSFS were compared. Results: The sensitivity and specificity of the m-BSFS was 79.2% and 66.0% respectively; and in children <4 years. improved to 81.2% and 75.0% respectively. There was poor agreement between hard stools by m-BSFS and the painful or hard bowel movement question of Rome Criteria. Conclusion: The potential utility of m-BSFS as a reasonably good tool to facilitate the diagnosis of potential constipation in children is shown. The poor agreement between painful or hard stool question in Rome III, and ratings for hard stool on the m-BSFS illustrates that one's perception may differ between a question and a picture. A useful pictorial tool to appraise stool form may, thus, be a favorable complement in the process of enquiry about bowel habits in well-child care.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.844-851
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• 2014

This study focused on the anti-oxidative and collagenase- and elastase inhibition effects of low molecular weight peptides (LMP) from commercial Jeju horse leg bone hydrolysates (JHLB) on pancreatin, via enzymatic hydrolysis. Cell viability of dermal fibroblasts exposed to UVB radiation upon treatment with LMP from JHLB was evaluated. Determination of the antioxidant activity of various concentrations of LMP from JHLB were carried out by assessing 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis-3-ethybenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity, ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC). The DPPH radical scavenging activity of LMP from JHLB (20 mg/mL) was 92.21% and ABTS radical scavenging activity (15 mg/mL) was 99.50%. FRAP activity (30 mg/mL) was $364.72{\mu}M/TE$ and ORAC activity (1 mg/mL) was $101.85{\mu}M/TE$. The anti-wrinkle potential was assessed by evaluating the elastase- and collagenase inhibition potential of these LMP. We found that 200 mg/mL of LMP from JHLB inhibited elastase activity by 41.32%, and 100 mg/mL of LMP from JHLB inhibited collagenase activity by 91.32%. The cell viability of untreated HS68 human dermal fibroblasts was 45% when exposed to a UVB radiation dose of $100mJ/cm^2$. After 24 h of incubation with $500{\mu}g/mL$ LMP from JHLB, the cell viability increased to 60%. These results indicate that LMP from JHLB has potential utility as an anti-oxidant and anti-wrinkle agent in the food and cosmetic industry. Additional in vivo tests should be carried out to further characterize these potential benefits.

• Food Science of Animal Resources
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• v.29 no.4
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• pp.423-429
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• 2009

The objective of this study was to investigate the potential of the application of lactic acid bacteria (LAB) from kimchi as a starter culture in the production of fermented sausages. To achieve this, a submerged model medium that contained LAB as part of a complex system of kimchi (0.5, 1.0, 1.0, 3.0, and 5.0%) and lyophilized kimchi powder (0.2 and 0.5%) was fermented for 120 h. During the fermentation period, the growth of total viable organisms and LAB, and the changes in the pH and the titratable acidity, were investigated. The initial LAB counts ranged from 6.4 to 7.7 Log CFU/mL for the kimchi media, and from 6.9 to 6.9 Log CFU/mL for the kimchi powder media. In all the kimchi batches, the LAB increased logarithmically, and the highest LAB counts (around 9 Log CFU/mL) were reached in 24 h. An evident lag phase of the LAB was observed in the kimchi powder samples and reached 8.8 Log CFU/mL in 8 h. The decrease in the pH and the formation of lactic acid were rapid in the kimchi batches, and reached pH values of 3.4-3.5 in 12 h. With these results, the LAB that was integrated with the addition of kimchi or kimchi powder demonstrated its potential utility as a substitute for starter culture.

• Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.98-103
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• 2009

The potential utility of the rockbream (Oplegnathus fasciatus) $\beta$-actin 5'-upstream sequence as a regulatory element for DNA vaccination was evaluated based on in vitro and in vivo heterologous expression assays. In the in vitro transfection experiment, the efficacy of the rockbream $\beta$-actin promoter to drive the expression of a downstream lacZ gene was significantly higher (more than fourfold) than that of the human cytomegalovirus (hCMV) promoter in two fish cell lines (grunt Haemulon plumierii fin and bluegill Lepomis macrochirus fry cell lines). In contrast, the functional activity of the rockbream $\beta$-actin promoter was hardly detectable in a mammalian mouse embryonic fibroblast cell line. Rockbream skeletal muscles injected in vivo with a GFP reporter construct driven by the $\beta$-actin promoter displayed the significantly higher expression of a GFP protein (more than threefold) than did those injected with hCMV promoter driven construct. Data from this study suggest that the homologous rockbream $\beta$-actin promoter could be used as a potential regulator for DNA vaccination in this species.

• Journal of Korean Society of Rural Planning
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• v.15 no.2
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• pp.97-110
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• 2009

The objective of this research was to develop a rural settlement demand model to analyze the determinants of settlement demand of urban residents. The point aimed at from model development was deriving stated preference of potential consumers towards rural settlement through setting a hypothetical market, and using settlement subsidy as a surrogate variable for price in the demand model. The adequate demand model deducted from hypothetical market data was derived from the basis of Hanemann's utility difference theory. In the rural settlement demand model, willingness to accept was expressed by a function of settlement subsidy. Data utilized in the analysis was collected from surveys of households nationwide. According to inferred results of the demand model, settlement subsidy had a significant influence on increasing demand for rural settlement. A significant common element was found among variables affecting demand increase through demand curve shift. The majority group of those with high rural settlement demand sought agricultural activity as their main motive, due to harsh urban environments aggravated by unstable job market conditions. Subsequently, restriction of income opportunities in rural areas does not produce an entrance barrier for potential rural settlers. Moreover, this argument could be supported by the common trend of those with high rural settlement demand generally tending to have low incomes. Due to such characteristics of concerned groups of rural settlement demand, they tended to react susceptibly to the subsidy provided by the government and local autonomous entities.

• Proceedings of the KSRS Conference
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• 2006.03a
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• pp.95-100
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• 2006

Measurements of ocean color from space since 1970s provided vital information with reference to physical and biogeochemical properties of the oceanic waters. The utility of these data has been explored in order to map and monitor highly toxic/or harmful algal blooms (HABs) that affected most of coastal waters throughout the world due to accelerated eutrophication from human activities and certain oceanic processes. However, the global atmospheric correction and bio-optical algorithms developed for oceanic waters were found to yield false information about the HABs in coastal waters. The present study aimed to evaluate the potential use of red tide index (RI) method, which has been developed by Ahn and Shanmugam (2005), for mapping of HABs in Korean and neighboring waters. Here we employed the SSMM to remove the atmospheric effect in the SeaWiFS image data and the achieved indices by RI method were found more appropriate in correctly identifying potential areas of the encountered HABs in Korean South Sea (KSS) and Chinese coastal waters during 1999-2004. But the existence of high absorbing and scattering materials greatly interfered with the standard OC4 algorithm which falsely identified red tides in these waters. In comparison with other methods, the RI approach for the early detection of HABs can provide state managers with accurate identification of the extent and location of these blooms as a management tool.

• Journal of Yeungnam Medical Science
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• v.30 no.1
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• pp.4-9
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• 2013

Leptin, a 16-kDa cytokine, is secreted by adipose tissue in response to the surplus of fat store. Thereby, the brain is informed about the body's energy status. In the hypothalamus, leptin triggers specific neuronal subpopulations (e.g., POMC and NPY neurons) and activates several intracellular signaling events, including the JAK/STAT, MAPK, PI3K, and mTOR pathway, which eventually translates into decreased food intake and increased energy expenditure. Leptin signal is inhibited by a feedback inhibitory pathway mediated by SOCS3. PTP1B involves another inhibitory pathway of leptin. Leptin potently promotes fat mass loss and body weight reduction in lean subjects. However, it is not widely used in the clinical field because of leptin resistance, which is a common feature of obesity characterized by hyperleptinemia and the failure of exogenous leptin administration to provide therapeutic benefit in rodents and humans. The potential mechanisms of leptin resistance include the following: 1) increases in circulating leptin-binding proteins, 2) reduced transport of leptin across the blood-brain barrier, 3) decreased leptin receptor-B (LRB), and/or 4) the provocation of processes that diminish cellular leptin signaling (inflammation, endoplasmic reticulum stress, feedback inhibition, etc.). Thus, interference of the cellular mechanisms that attenuate leptin signaling improves leptin action in cells and animal models, suggesting the potential utility of these processes as points of therapeutic intervention. Various experimental trials and compounds that improve leptin resistance are introduced in this paper.