• Title/Summary/Keyword: ageing treatment

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The Graft Polymerization of Acrylic Acid in Vapour Phase onto Poly(ethylene terephthalate) by Cold Plasma Part (I) (저온 Plasma를 이용한 Poly(ethylene terephthalate)에의 Acrylic Acid의 기상 Graft 공중합 반응(I))

  • 천태일;최석철;모상영
    • Textile Coloration and Finishing
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    • v.1 no.1
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    • pp.7-18
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    • 1989
  • The distinguishing characteristic of the glow discharge is that chemical reaction induced by partially ionized gases are limited only to the substrate surface. Most studies have been done on the plasma etching and polymerization. The graft polymerization in vapour phase by cold plasma has been rarely investigated. In this study the system of tub3ar reaction chamber with capacitively coupled electrode of alternative current of 60 Hz was employed for the graft polymerization. The graft polymerization of Acylic Acid(AA) onto the poly (ethylene terephthalate) (PET) was carried out by treatment of PET film and fabric by cold plasma (glow discharge of argon gas), followed by the supply of AA vapour. The graft yield was about 1 wt%. The surface property was determined by contact angle, the surface tension was evaluated by zisman’s plot and equation of surface tension mesurement. The results were as follows: 1. In order to obtain lower contact angle, it was effective to avoid the vicinity of electrodes for a setting position of substrate. 2. Contact angle affected on the monomer pressure and its duration of exposure to the acid vapour. 3. Polymer radical formation was influenced by the changes of the value of current density and plasma treatment time. 4. Total surface tension of plasma grafted PET film increased. With an increase in the carboxylic acid content, the dispersion force decreased, while, the polar force and hydrogen bonding force increased. 5. The contact angle decreased from $75^\circ$ to around $30^\circ$ by plasma grafting. There was no ageing effect on the contact angle after 4 months.

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Evaluation of shear bond strength of repair acrylic resin to Co-Cr alloy

  • Kulunk, Safak;Kulunk, Tolga;Sarac, Duygu;Cengiz, Seda;Baba, Seniha
    • The Journal of Advanced Prosthodontics
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    • v.6 no.4
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    • pp.272-277
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    • 2014
  • PURPOSE. The purpose of this study was to investigate the impact of different surface treatment methods and thermal ageing on the bond strength of autopolymerizing acrylic resin to Co-Cr. MATERIALS AND METHODS. Co-Cr alloy specimens were divided into five groups according to the surface conditioning methods. C: No treatment; SP: flamed with the Silano-Pen device; K: airborne particle abrasion with $Al_2O_3$; Co: airborne particle abrasion with silica-coated $Al_2O_3$; KSP: flamed with the Silano-Pen device after the group K experimental protocol. Then, autopolymerized acrylic resin was applied to the treated specimen surfaces. All the groups were divided into two subgroups with the thermal cycle and water storage to determine the durability of the bond. The bond strength test was applied in an universal test machine and treated Co-Cr alloys were analyzed by scanning electron microscope (SEM). Two-way analysis of variance (ANOVA) was used to determine the significant differences among surface treatments and thermocycling. Their interactons were followed by a multiple comparison' test performed uing a post hoc Tukey HSD test (${\alpha}=.05$). RESULTS. Surface treatments significantly increased repair strengths of repair resin to Co-Cr alloy. The repair strengths of Group K, and Co significantly decreased after 6,000 cycles (P<.001). CONCLUSION. Thermocycling lead to a significant decrease in shear bond strength for air abrasion with silica-coated aluminum oxide particles. On the contrary, flaming with Silano-Pen did not cause a significant reduction in adhesion after thermocycling.

An Analysis Of The Differences In Medical Use By Region (지역에 따른 의료이용의 차이 분석)

  • Seo, Woo-Soon;Kim, Jae-Hyun;Lee, Ok-Hee
    • Korea Journal of Hospital Management
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    • v.25 no.1
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    • pp.13-20
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    • 2020
  • Purposes: This study has the purpose to the improvement of health promotion for local residents through delivery of high-quality medical service by improving imbalance of medical use and seeking an improvement plan for accessibility of effective medical service by understanding the pattern of medical use by region. Methodology: As for the method, this study derived results at the significance level of p<0.05 through chi square test(χ2 test) and Generalized Estimating Equation(GEE) SAS 9.4 version by using the data of the 7th Korean Longitudinal Study of Ageing 2018. Findings: Study results show that local residents use medical service such as hospitalization care and outpatient visit more as compared to the residents in Gyeonggi-do/large or medium-sized cities. The more the number of chronic disease, the more they select hospitalization care rather than outpatient visit. Results also show that patients engaged in labour tend to select outpatient treatment rather than hospitalization treatment. Meanwhile, severity of disease turned out to be higher amongst medical care beneficiaries than that of national health insurance patients when comparing the types of medical security. Practical Implications: In stead of solving the problem of the difference in medical use by region from the aspect of income and economic level, an integrative solution shall be provided putting viewpoint on the social phenomenon suited to the changes of the times. This study suggests a plan for using a health and medical community care center that acts as a gate keeper of regional medical service.

Dry-heat Treatment Effect for Seed Longevity Prediction in Rice Germplasm (벼 유전자원의 저장수명 예측을 위한 건열처리 효과)

  • Na, Young-Wang;Baek, Hyung-Jin;Choi, Yu-Mi;Lee, Sok-Young;Lee, Jung-Ro;Chung, Jong-Wook;Park, Yong-Jin;Kim, Seok-Hyeon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.59 no.3
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    • pp.230-238
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    • 2014
  • The purpose of this study was to develop the cost-effective and efficiency seed longevity prediction method of rice (Oryza sativa L.) germplasm for viability monitoring. To find an optimum predicting method for rice seed longevity at genebank, an accelerated ageing (AA) test, a controlled deterioration (CD) test and a dry-heat treatment (DHT) were conducted to the four groups of rice germplasm based on ecotype, such as Indica, Japonica, Javanica and Tongil type. Among the three artificial aging treatments, the dry-heat treatment of 36 hours at $90^{\circ}C$ is suggested as a routine predictive test method of rice germplasm longevity at a genebank. The distribution of germination rate on 3,066 accessions which conserved 26.5 years at $4^{\circ}C$ showed similar trend with the result of distribution by dry-heat treatment at $90^{\circ}C$ on 36 hours using 106 accessions of rice selected samples which composed four ecotype groups. The results show that the dry-heat treatment affect not only predicting the rice seed longevity but also determining effective interval for monitoring germination of rice germplasm in genebanks.

Effects of Submersion Aging in Chilled Water on Tenderness and Microbial Growth of Vacuum-Packed Hanwoo Meat (냉수침지 숙성법이 진공포장 한우육의 연도 및 미생물 증식에 미치는 효과)

  • 주선태;이한기;강근호;신철우;양한술;문성실;이정일;김영환;박구부
    • Food Science of Animal Resources
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    • v.22 no.3
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    • pp.228-233
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    • 2002
  • To investigate the effects of submersion aging in chilled water on tenderness and microbial growth of vacuum-packed beef, the semimembranosus muscles of Hanwoo (Korean cattle) was sampled at a commercial meat plant at 24 hrs postmortem. The samples were cut to 2.5 cm thick steaks and randomly assigned to following two treatments. The samples were stored in conventional refrigerator at 4$^{\circ}C$ after vacuum packaging for control whereas the other vacuum-packed samples were submersed in chilled water at 1$^{\circ}C$ for treatment, and both samples were stored for 14 days to measure total plate counts (TPC), sarcomere length, free calcium concentration, shear farce value and myofibrillar fragmentation index (MFI). The sarcomere length of treatment was significantly (p<0.05) longer than that of control at 3 days aging. Result suggested that submersion in chilled water of vacuum-packed beef might be effective to improve tenderness of meat compared to storage in conventional refrigerator. There were no significant differences in the shear force and MFI between control and treatment during storage. However, the free calcium concentration of samples from treatment was significantly (p<0.05) higher than that of control at 7 days of ageing. This result indicated that the lower shear force value and the longer sarcomere length of samples from treatment might be due to increasing the free calcium ion concentration in sarcoplasm during storage. On the other hands, samples from control showed significantly (p<0.05) higher number of microbial (TPC) compared to treatment during storage. from results obtained, submersion in chilled water of vacuum-packed beef could be recommended as a desirable aging method to improve tenderness of Hanwoo compared to aging in conventional refrigerator.

Estimation of the Cost of Hypertension Disease Loss in 2010-2017 Using Cohort at Diagnosis Age and Treatment Time (진단나이 및 치료시점 코호트를 활용한 2010~2017년 고혈압 질환 손실비 추계)

  • Noh, Yun-Gon;Lee, Sang-Ho;Choi, Kyungsik;Song, Tae Min
    • The Journal of the Korea Contents Association
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    • v.22 no.2
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    • pp.782-793
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    • 2022
  • The rise in chronic disease not only has a negative effect on people's lives, but it also increases the cost of medical care owing to the increased usage of medical care as health and medical technology improves, life expectancy rises, and rapid population ageing. In such context, this study examined the difference in the disease cost of hypertension according to demographic information and the effect of the initial diagnosis age and treatment period on the cost. This study used the Korean Health Panel Survey from 2010 to 2017, and selected subjects based on health insurance beneficiaries between the ages of 30 and under 80. With the selected data, the direct and indirect costs of disease loss were calculated according to the cost of illness approach, and we constructed a disease-loss ratio cohort considering the age of diagnosis and time of treatment for hypertension. From the results of the study, the annual cost of disease loss for hypertensive patients differed by gender by 110,107 won, and it was found that the cost increased by 1.8 times as the treatment time increased. In addition, when comparing disease loss ratios between the same age groups, it was found that the disease loss ratios between those in their 60s and 70s were affected by treatment time. This study confirmed that hypertension significantly affects the cost of the disease, and not only requires early diagnosis and management, but also preventive efforts to lower the incidence of hypertensive disease must be strengthened.

Vitamin D Attenuates Pain and Cartilage Destruction in OA Animals via Enhancing Autophagic Flux and Attenuating Inflammatory Cell Death

  • JooYeon Jhun;Jin Seok Woo;Ji Ye Kwon;Hyun Sik Na;Keun-Hyung Cho;Seon Ae Kim;Seok Jung Kim;Su-Jin Moon;Sung-Hwan Park;Mi-La Cho
    • IMMUNE NETWORK
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    • v.22 no.4
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    • pp.34.1-34.19
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    • 2022
  • Osteoarthritis (OA) is the most common form of arthritis associated with ageing. Vitamin D has diverse biological effect on bone and cartilage, and observational studies have suggested it potential benefit in OA progression and inflammation process. However, the effect of vitamin D on OA is still contradictory. Here, we investigated the therapeutic potential of vitamin D in OA. Six-week-old male Wistar rats were injected with monosodium iodoacetate (MIA) to induce OA. Pain severity, cartilage destruction, and inflammation were measured in MIA-induced OA rats. Autophagy activity and mitochondrial function were also measured. Vitamin-D (1,25(OH)2D3) and celecoxib were used to treat MIA-induced OA rats and OA chondrocytes. Oral supplementation of vitamin D resulted in significant attenuations in OA pain, inflammation, and cartilage destruction. Interestingly, the expressions of MMP-13, IL-1β, and MCP-1 in synovial tissues were remarkably attenuated by vitamin D treatment, suggesting its potential to attenuate synovitis in OA. Vitamin D treatment in OA chondrocytes resulted in autophagy induction in human OA chondrocytes and increased expression of TFEB, but not LC3B, caspase-1 and -3, in inflamed synovium. Vitamin D and celecoxib showed a synergistic effect on antinociceptive and chondroprotective properties in vivo. Vitamin D showed the chondroprotective and antinociceptive property in OA rats. Autophagy induction by vitamin D treatment may be a promising treatment strategy in OA patients especially presenting vitamin D deficiency. Autophagy promoting strategy may attenuate OA progression through protecting cells from damage and inflammatory cell death.

The Burden of Cancer in Member Countries of the Association of Southeast Asian Nations (ASEAN)

  • Kimman, Merel;Norman, Rosana;Jan, Stephen;Kingston, David;Woodward, Mark
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.2
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    • pp.411-420
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    • 2012
  • This paper presents the most recent data on cancer rates and the burden of cancer in the ASEAN region. Epidemiological data were sourced from GLOBOCAN 2008 and disability adjusted life years (DALYs) lost were estimated using the standard methodology developed within the World Health Organization's Global Burden of Disease study. Overall, it was estimated there were over 700,000 new cases of cancer and 500,000 cancer deaths in ASEAN in the year 2008, leading to approximately 7.5 million DALYs lost in one year. The most commonly diagnosed cancers were lung (98,143), breast (86,842) and liver cancers (74,777). The most common causes of cancer death were lung cancer (85,772), liver cancer (69,115) and colorectal cancer (44,280). The burden of cancer in terms of DALYs lost was highest in Laos, Viet Nam and Myanmar and lowest in Brunei, Singapore and the Philippines. Significant differences in the patterns of cancer from country to country were observed. Another key finding was the major impact played by population age distribution on cancer incidence and mortality. Cancer rates in ASEAN are expected to increase with ageing of populations and changes in lifestyles associated with economic development. Therefore, ASEAN member countries are strongly encouraged to put in place cancer-control health care policies, focussed on strengthening the health systems to cope with projected increases in cancer prevention, treatment and management needs.

Sarcopenia: Nutrition and Related Diseases

  • Du, Yang;No, Jae Kyung
    • Culinary science and hospitality research
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    • v.23 no.1
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    • pp.66-78
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    • 2017
  • "Sarcopenia", sarcopenia is an old age syndrome, and used to describe the reduction of skeletal muscle. Initially, it was thought that sarcopenia was only a senile disease characterized by degeneration of muscle tissue. However, its cause is widely regarded as multifactorial, with neurological decline, hormonal changes, inflammatory pathway activation, declines in activity, chronic illness, fatty infiltration, and poor nutrition, all shown to be contributing factors. Skeletal muscle mass can be measured by a variety of methods, currently, the commonly used methods are dual-energy X-ray scanning (DXA), computer tomography (CT), magnetic resonance imaging (MRI), etc. Muscular skeletal disorders can also be assessed by measuring appendicular skeletal muscle (ASM), particularly muscle tissue content. At the same time, sarcopenia refers to skeletal muscle cell denervation, mitochondrial dysfunction, inflammation, hormone synthesis and secretion changes and a series of consequences caused by the above process and is a progressive loss of skeletal muscle syndrome, which can lead to the decrease of muscle strength, physical and functional disorders, and increase the risk of death. Sarcopenia is mainly associated with the aging process, but also related to other causes such as severe malnutrition, neurodegenerative diseases, and disuse and endocrine diseases associated with muscular dystrophy, and it is the comprehensive results of multi-factors, so it is difficult to define that sarcopenia is caused by a specific disease. With the aging problem of the population, the incidence of this disease is increasingly common, and seriously affects the quality of the life of the elderly. This paper reviews the etiology and pathogenesis of myopathy, screening methods and diagnosis, the influence of eating habits, etc, and hopes to provide reference for the diagnosis and treatment of this disease. At present, adequate nutrition and targeted exercise remain the gold standard for the therapy of sarcopenia.

A Study on Ageing Characteristics and Alloy Elements of SiCp Reinforced Al Matrix Composites (SiCp입자강화 Al 복합재료에 대한 합금원소의 영향과 시효특성에 관한 연구)

  • Kim, Sug-Won;Lee, Ui-Jong;Woo, Kee-Do;Kim, Dong-Keun
    • Journal of Korea Foundry Society
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    • v.21 no.1
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    • pp.7-14
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    • 2001
  • The research on new DRA(discontinuous reinforced alloy) and CRA(continous reinforced alloy) composites has been carried out to improve the properties of ceramic fiber and particle reinforced metal matrix composites(MMCs). Effects of alloying elements and aging conditions on the microstructures and aging behavior of Al-Si-Cu-Mg-(Ni)-SiCp composite have been examined. The specimens used in this study were manufactured by duplex process. The first squeeze casting is the process to make precomposite and the second squeeze casting is the process to make final composite. The hardening behavior was accelerated with decreasing the size of SiCp particle in the composites. It is considered that the dislocation density increased with increasing SiCp size, due to the different thermal deformation between Al matrix and SiCp during quenching after the solution treatment. Peak aging time to obtain the maximum hardness in 3 ${\mu}m$ SiCp reinforced Al composite was reduced than that in large size(5, 10 ${\mu}m$) of SiCp because of difference in dislocation density. Aging hardening responce(${\Delta}H$ = $H_{Max}.-H_{S.T}$) of composites was greater than that of unreinforced Al alloy because of higher density of second phases in matrix.

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