• International Area Studies Review
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• v.12 no.2
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• pp.125-145
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• 2008

Japan is now facing an aging society with fewer children. According to the demographic change in Japan, its economic effect on the economic growth has gained public attention. This paper focuses on the effect of the demographic change on economic growth in Japan, too. The first part illustrates the process of demographic transition in Japan. Thanks to successful Meiji Revitalizing Reform, Japan had experienced demographic transition earlier than the other East Asia countries. The second part of this paper describes relations between demographic factors and economic growth theoretically. In addition, it analyzes demographic effects on economic growth empirically using time series data of Japan from 1952 to 2005. It is the main finding of analyses that there are positive relations between demographic factor, including employment population rate, population rate and TFR, and economic growth. Therefore, in the near future, a decreasing labor force will cause economic stagnation in Japan. To overcome this problems, it is required to make various policies.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.51-55
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• 2019

The loss of safety for reservoirs brought about by climate change and facility aging leads to reservoir failures, which results in the loss of lives and property damage in downstream areas. Therefore, it is necessary to provide a Reservoir Failure Forecasting System for downstream residents to detect the early signs of failure (with sensors) in real-time and perform safety management to prevent and minimize possible damage. For the verification of established water level management criteria, 10 water level data up to reservoir capacity was selected. Weight factor and trend line were applied to dramatic increase section of water level in the 1 year period data. The results shows that water level criteria based on three even parts shows less than 7% of standard deviation and it is appropriate to verify management criteria.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.285-291
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• 2019

This study was conducted to identify the factors influencing health-related quality of life of urinary incontinent elderly women. The Korea National Health and Nutrition Examination Survey (KNHANES) conducted by the Korea Centers for Disease Control and Prevention (KCDC) was used as baseline data to evaluate how activity limitation, depression experience and subjective health perception influence the health-related quality of life of urinary incontinent elderly women. The urinary incontinent elderly women differed significantly in terms of activity limitation, depression experience, subjective health perception influence and health-related quality of life compared to elderly women without incontinence. In contrast, income and education were not correlated with either of the aforementioned groups. The subjective health perception was identified as the only factor influencing the health-related quality of life of urinary incontinent elderly women. The results of this study will serve as basic data for positive treatment promotion and development of assessment programs for incontinence patients who recognize incontinence symptoms as part of the aging process and are therefore unwilling to receive care.

• Parasites, Hosts and Diseases
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• v.57 no.2
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• pp.117-125
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• 2019

Malarial infection induces tissue hypoxia in the host through destruction of red blood cells. Tissue hypoxia in malarial infection may increase the activity of $HIF1{\alpha}$ through an intracellular oxygen-sensing pathway. Activation of $HIF1{\alpha}$ may also induce vascular endothelial growth factor (VEGF) to trigger angiogenesis. To investigate whether malarial infection actually generates hypoxia-induced angiogenesis, we analyzed severity of hypoxia, the expression of hypoxia-related angiogenic factors, and numbers of blood vessels in various tissues infected with Plasmodium berghei. Infection in mice was performed by intraperitoneal injection of $2{\times}10^6$ parasitized red blood cells. After infection, we studied parasitemia and survival. We analyzed hypoxia, numbers of blood vessels, and expression of hypoxia-related angiogenic factors including VEGF and $HIF1{\alpha}$. We used Western blot, immunofluorescence, and immunohistochemistry to analyze various tissues from Plasmodium berghei-infected mice. In malaria-infected mice, parasitemia was increased over the duration of infection and directly associated with mortality rate. Expression of VEGF and $HIF1{\alpha}$ increased with the parasitemia in various tissues. Additionally, numbers of blood vessels significantly increased in each tissue type of the malaria-infected group compared to the uninfected control group. These results suggest that malarial infection in mice activates hypoxiainduced angiogenesis by stimulation of $HIF1{\alpha}$ and VEGF in various tissues.

• Journal of Information Technology Applications and Management
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• v.26 no.1
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• pp.21-38
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• 2019

This study starts from the question, "Are people of the age 60 and over equally 'old?' "As the aging population has rapidly become a global issue, it is a timely question to think about whether it is appropriate to classify people aged 60 and over as senior citizens monolithically based on their chronological age. Thanks to the advancement of medical technology and ever-increasing life expectancy, there may be more differences than we thought in terms of cognitive and behavioral patterns among the elderly population. In order to further investigate this question, this study focuses on technology acceptance behavior of 132 participants over the age of 60 towards a wearable healthcare device. The results show that there were interesting behavioral differences among participants depending on their cognitive capabilities. More specifically, participants with high cognitive capability (Superagers) consider the usefulness and the social aspects (social norm and image) of using wearable healthcare technology. Whereas for those with relatively low cognitive capability (non-Superagers), usefulness of using the technology was not a significant factor, and they mainly considered social norm and image. Our findings imply that the current monolithic application of chronological age to classify the elderly population should be carefully reconsidered because people aged over 60 years old may not always share homogeneous cognitive and behavioral patterns.

• Clinical and Experimental Otorhinolaryngology
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• v.11 no.4
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• pp.250-258
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• 2018

Objectives. To compare narrative skills between fourth and fifth grades of Persian-speaking students with hearing impairments and typical hearing students of the same grade and also to evaluate the effects of group, sex, hearing age, and educational grade of the students on their spoken/written narrative performance. Methods. The subjects were 174 students aged 10-13 years, 54 of whom wore cochlear implants, 60 suffered from moderate to severe hearing losses and wore hearing aids, with the remaining 60 students being typical hearing in terms of the sense of hearing. The micro- and macrostructure components of spoken and written narrative were elicited from a pictorial story (The Playful Little Elephant) and then scored by raters. Results. Compared to the typical hearing, the students with hearing impairments had significantly lower scores in all of the microstructure components of narratives. However, the findings showed no significant difference among different groups in macrostructure components of narratives. It was also revealed that the students had equal performance in spoken and written narrative. Finally, factor analysis manifested that group, sex, hearing age, and educational level of children might alter the outcome measures in various interactions. Conclusion. Although cochlear implantation was more effective than hearing aid on spoken and written narrative skills, the Persian-speaking students with hearing impairments were seen to need additional trainings on microstructure components of spoken/written narrative.

• Archives of Plastic Surgery
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• v.48 no.1
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• pp.26-32
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• 2021

Background Although loss of sensation in patients with breast cancer after mastectomy followed by breast reconstruction is an important factor affecting patients' quality of life, the mechanism of sensory recovery is still unclear. Our study aimed to identify variables that affect sensory recovery, especially pain, in reconstructed breasts. Methods All patients with breast cancer who underwent mastectomy followed by immediate breast reconstruction, including nipple reconstruction or areolar tattooing, were included in this study. Sensation was evaluated in the nipple as an endpoint of sensation recovery of the whole breast. Patients rated pain severity using a 3-point verbal rating scale (VRS): grade 0, no pain; grade 1, mild to moderate pain; and grade 2, severe pain. The VRS was assessed by a single experienced plastic surgeon. Results In the univariate analysis, the odds ratio (OR) for sensation recovery was 0.951 for age (P=0.014), 0.803 for body mass index (P=0.001), 0.996 for breast volume before surgery (P=0.001), 0.998 for specimen weight after mastectomy (P=0.040), and 1.066 for the period between mastectomy and sensory assessment (P=0.003). In the multivariate analysis, the variables that showed a significant effect were age (OR, 0.953; P=0.034), the period between mastectomy and sensory assessment (OR, 1.071; P=0.006), and reconstruction using abdominal tissue instead of prosthetic reconstruction (OR, 0.270; P=0.004). Conclusions Based on our results, it can be inferred that aging has a negative impact on the recovery of sensation, breast sensation improves with time after surgery, and the recovery of sensation is better in prosthetic reconstruction.

• Smart Structures and Systems
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• v.24 no.5
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• pp.669-681
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• 2019

Bridge collapses may deliver a huge impact on our society in a very negative way. Out of many reasons why bridges collapse, poor maintenance is becoming a main contributing factor to many recent collapses. Furthermore, the aging of bridges is able to make the situation much worse. In order to prevent this unwanted event, it is indispensable to conduct continuous bridge monitoring and timely maintenance. Visual inspection is the most widely used method, but it is heavily dependent on the experience of the inspectors. It is also time-consuming, labor-intensive, costly, disruptive, and even unsafe for the inspectors. In order to address its limitations, in recent years increasing interests have been paid to the use of unmanned aerial vehicles (UAVs), which is expected to make the inspection process safer, faster and more cost-effective. In addition, it can cover the area where it is too hard to reach by inspectors. However, this strategy is still in a primitive stage because there are many things to be addressed for real implementation. In this paper, a typical procedure of bridge inspection using UAVs consisting of three phases (i.e., pre-inspection, inspection, and post-inspection phases) and the detailed tasks by phase are described. Also, three major challenges, which are related to a UAV's flight, image data acquisition, and damage identification, respectively, are identified from a practical perspective (e.g., localization of a UAV under the bridge, high-quality image capture, etc.) and their possible solutions are discussed by examining recently developed or currently developing techniques such as the graph-based localization algorithm, and the image quality assessment and enhancement strategy. In particular, deep learning based algorithms such as R-CNN and Mask R-CNN for classifying, localizing and quantifying several damage types (e.g., cracks, corrosion, spalling, efflorescence, etc.) in an automatic manner are discussed. This strategy is based on a huge amount of image data obtained from unmanned inspection equipment consisting of the UAV and imaging devices (vision and IR cameras).

• Food Science of Animal Resources
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• v.41 no.4
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• pp.623-635
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• 2021

The effect of deer antler extract on muscle differentiation and muscle atrophy were evaluated to minimize muscle loss following aging. Various deer antler extracts (HWE, hot water extract of deer antler; FE, HWE of fermented deer antler; ET, enzyme-assisted extract of deer antler; UE, extract prepared by ultrasonication of deer antler) were evaluated for their effect on muscle differentiation and inhibition of 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR)-induced muscle atrophy in C2C12 cells. Morphological changes according to the effect of antler extracts on muscle differentiation were confirmed by Jenner-Giemsa staining. In addition, the expression levels of genes related to muscle differentiation and atrophy were confirmed through qRT-PCR. In the presence of antler extracts, the length and thickness of myotubes and myogenin differentiation 1 (MyoD1) and myogenic factor 5 (Myf5) gene expression were increased compared to those in the control group (CON). Gene expression of AMP-activated protein kinase (AMPK), MyoD1, and myogenin, along with the muscle atrophy factors muscle RING finger-1 (MuRF-1) and forkhead box O3a (FoxO3a) upon addition of deer antler extracts to muscle-atrophied C2C12 cells was determined by qRT-PCR after treatment with AICAR. The expression of MuRF-1 and FoxO3a decreased in the groups treated with antler extracts compared to that in the group treated with AICAR alone. In addition, gene expression of MyoD1 and myogenin in the muscle atrophy cell model was significantly increased compared that into the CON. Therefore, our findings indicate that antler extract can increase the expression of MyoD1, Myf5 and myogenin, inhibit muscle atrophy, and promote muscle differentiation.

• Journal of Marine Bioscience and Biotechnology
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• v.13 no.1
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• pp.1-9
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• 2021

Codium fragile (Suringar) Hariot, a green alga of the Codiales family, has been reported to have several bioactive properties, including antioxidant and anti-inflammatory properties. However, its antiobesity and whitening effects and their underlying mechanisms are unclear. This study aimed to evaluate the antiobesity and melanogenesis inhibitory effects of C. fragile using methanol extracts of C. fragile (MECF). The results of this study revealed that MECF inhibited the accumulation of lipid droplets and triacylglycerol in differentiated 3T3-L1 adipocytes, which was associated with the inhibition of the expression of adipogenesis-related transcription factors, such as peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein-α (C/EBPα), and C/EBPβ, which function as the key regulators of adipogenesis. Also, MECF reduced tyrosinase activity and melanin content in B16F10 cells as well as the expression of tyrosinase, tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-related transcription factor in the presence of α-melanocyte-stimulating hormone. Taken together, our findings suggest that the extract of C. fragile could be considered a promising functional ingredient for the prevention and treatment of obesity and skin pigmentation in the food and cosmetic industry.