• Journal of the Korean Society for Heat Treatment
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• v.28 no.5
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• pp.229-238
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• 2015

The effects of Sn addition and solution treatment on corrosion behavior were studied in AZ91 magnesium casting alloy. The addition of 5%Sn contributed to the introduction of $Mg_2Sn$ phase, to the reduction in dendritic cell size and to the increase in the amount of secondary phases. After the solution treatment, trace amount of $Al_8Mn_5$ particles were observed in the ${\alpha}$-(Mg) matrix for the AZ91 alloy, while $Mg_2Sn$ phase with high thermal stability was additionally found in the AZ91-5%Sn alloy. Before the solution treatment, the AZ91-5%Sn alloy had better corrosion resistance than the Sn-free alloy, which is caused by the enhanced barrier effect of the (${\beta}+Mg_2Sn$) phases formed more continuously along the dendritic cell boundaries. It is interesting to note that after the solution treatment, the corrosion rate of both alloys became increased, but the Sn-added alloy showed higher corrosion rate than the Sn-free alloy. The microstructural examination on the corroded surfaces revealed that the remaining $Mg_2Sn$ particles in the solution-treated AZ91-5%Sn alloy play a role in accelerating corrosion by galvanic coupling with the ${\alpha}$-(Mg) matrix.

• Journal of Preventive Medicine and Public Health
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• v.33 no.4
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• pp.513-520
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• 2000

Objectives : To estimate the prevalence of hypertension, rates of awareness, treatment modalities, and control of hypertension, and also to identify factors in rural Korea that are related to these aspects of hypertension. Methods : A cross-sectional survey, including blood pressure(BP) measurements and interviews, investigating the variables in the health belief model was peformed from August to November, 1999 on 1,426 (79.4%) study subjects out of 1,797 registered residents over 30 years old in Ibansong-Myun, Chinju City. A second survey was peformed from January to March, 2000 on 376 (80.0%) subjects out of 470 hypertensive (or suspected hypertensive) subjects found in the first survey. Two BP readings were taken in each survey using a standard mercury sphygmomanometer. Hypertension was defined as either a BP reading $\geq$ 140/90 mmHg in both surveys, or as subjects on oral hypertensive medication. Results : Estimated hypertension prevalence was 24.9% for men, and 30.4% for women. Rates of hypertension awareness, treatment (the regular use of oral hypertensives), and control (reduction of BP to <140/90 mmHg) were 52.5%, 34.4%, and 12.9%, respectively. The factors related to lower hypertension awareness in the logistic regression analysis were male gender, farming occupation, and higher perceived barrier to medical treatment (those for whom visiting health professionals is a burden). Conclusions : To improve the low awareness, treatment, and control of hypertension, a more active and out-reaching hypertension control program, including routine BP measurements for every visitor to primary care facilities, is needed in rural Korea.

• International Journal of Industrial Entomology and Biomaterials
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• v.38 no.2
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• pp.25-30
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• 2019

Atmospheric-pressure plasma technique is a technology for sterilizing agricultural product. In this study, dielectric barrier discharge plasma was applied to silkworm powder for 1 to 5 h with less than 2 ppm of $O_3$ and $NO_2$. Quantitative compositions including proximate contents, mineral and heavy metal contents, fatty acids, vitamins, and DNJ contents were measured. Proximate contents of silkworm powder were protein (57.2%), fat (9.9%), fiber (4.6%), ash (10.1%), and moisture (5.7%). These compositions were not affected by the treatment of plasma. Silkworm powder has 5 abundant minerals potassium (K), phosphorus (P), sulfur (S), calcium (Ca), and magnesium (Mg). Among these minerals, plasma treatment decreased the contents of P and S sharply from 732.3 to 176.8, and 492.7 to 185.2 mg/100g, respectively. Heavy metal contents including lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) were not detected in the silkworm powder. Five vitamins such as ascorbic acid (13.6 mg/100g), riboflavin (5.4 mg/100g), ${\beta}$-carotene (1.8 mg/100g), niacin (0.6 mg/100g), and thiamine (0.4 mg/100g) were not significantly changed by plasma treatment. Silkworm powder is composed of 30 parts saturated fatty acids and 70 parts unsaturated ones. The fatty acid composition was not significantly changed by plasma treatment. The DNJ content of silkworm powder (3.72 mg/g) was also nearly constant within the experimental condition of plasma treatment.

• Korean journal of dermatology
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• v.56 no.10
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• pp.581-593
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• 2018

Atopic dermatitis (AD) is a common, chronic, relapsing, inflammatory skin disease that affects both children and adults. AD is the cause of considerable morbidity including severe pruritus and impaired quality of life. Treatments for active disease include avoidance of triggering factors, barrier repair, topical medications including topical corticosteroids (TCs) and topical calcineurin inhibitors (TCIs), phototherapy, antibacterial agents, and systemic immunosuppressants including cyclosporine. Until recently, the only Food and Drug Administration (FDA)-approved systemic treatment options for patients with moderate-to-severe AD were steroids and cyclosporine. Systemic steroids are not recommended by current guidelines and are commonly associated with disease rebound. Instead, clinicians choose from several off-label immunosuppressants. In 2018, the Korean FDA approved dupilumab for adults with moderate-to-severe AD whose disease is not adequately controlled with topical therapies. The implementation of treatment guidelines for AD is challenging. Herein, we review the several treatment modalities for AD and recommend a treatment algorithm.

• Animal Bioscience
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• v.36 no.5
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• pp.810-817
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• 2023

Objective: The aim was to compare the behavioral response to full separation of cows and calves maintained together for 100 days or 24 h. Methods: Twelve Holstein-Friesian cow-calf pairs were enrolled into either treatment or industry groups (n = 6 cow-calf pairs/group). The treatment cows and calves were maintained on pasture together for 106±8.6 d and temporarily separated twice a day for milking. The Industry cows and their calves, were separated within 24 h postpartum. Triaxial accelerometer neck-mounted sensors were fitted to cows 3 weeks before separation to measure hourly rumination and activity. Before separation, cow and calf behavior was observed by scan sampling for 15 min. During the separation process, frequency of vocalizations and turn arounds were recorded. At separation, cows were moved to an observation pen where behavior was recorded for 3 d. A CCTV camera was used to record video footage of cows within the observation pens and behavior was documented from the videos in 15 min intervals across the 3 d. Results: Before separation, industry calves were more likely to be near their mother than Treatment calves. During the separation process, vocalization and turn around behavior was similar between groups. After full separation, treatment cows vocalized three times more than industry cows. However, the frequency of time spent close to barrier, standing, lying, walking, and eating were similar between industry and treatment cows. Treatment cows had greater rumination duration, and were more active, than industry cows. Conclusion: These findings suggest a similar behavioral response to full calf separation and greater occurrence of vocalizations, from cows maintained in a long-term, pasture-based, cow-calf rearing system when ompared to cows separated within 24 h. However, further work is required to assess the impact of full separation on calf behavior.

• Journal of Environmental Science International
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• v.23 no.9
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• pp.1627-1634
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• 2014

Odor control technology include absorption, adsorption, incineration and biological treatments. But, most of processes have some problems such as secondary organic acids discharge at the final odor treatment facility. In order to solve the problems for effective treatment of organic acids in odor, it is necessary to develop a new type advanced odor control technology. Some of the technology are plasma only process and plasma hybrid process as key process of the advanced technology. In this study, odor removal performance was compared DBD(Dielectric Barrier Discharge)plasma process with PCHP(plasma catalysis hybrid process) by gaseous ammonia, formaldehyde and acetic acid. Plasma only process by acetic acid obtained higher treatment efficiency above 90%, and PCHP reached its efficiency up to 96%. Acetic acid is relatively easy pollutant to control its concentration other than sulfur and nitrogen odor compounds, because it has tendency to react with water quickly. To test of the performance of DBD plasma process by applied voltage, the tests were conducted to find the dependence of experimental conditions of the applied voltage at 13 kV and 15 kV separately. With an applied voltage at 15 kV, the treatment efficiency was achieved to more higher than 13 kV from 83% to 99% on ammonia, formaldehyde and acetic acid. It seems to the odor treatment efficiency depends on the applied voltage, temperature, humidity and chemical bonding of odors.

• Electrical & Electronic Materials
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• v.8 no.5
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• pp.619-625
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• 1995

Polycrystalline CdTe thin film has been studied for photovoltaic application due to the 1.45 eV band gap energy ideal for solar energy conversion and high absorption coefficient. The formation of low resistance contact to p-CdTe is difficult because of large work function(>5.5eV). Common methods for ohmic contact to p-CdTe are to form a p+ region under the contact by in-diffusion of contact material to reduce the barrier height and modify a p-CdTe surface layer using chemical treatment. In this study, the surface chemical treatment of p CdTe was carried out by H$\_$3/PO$\_$4/+HNO$\_$3/ or K$\_$2/Cr$\_$2/O$\_$7/+H$\_$2/SO$\_$4/ solution to provide a Te-rich surface. And various thin film contact materials such as Cu, Au, and Cu/Au were deposited by E-beam evaporation to form ohmic contact to p-CdTe. After the metallization, post annealing was performed by oven heat treatment at 150.deg. C or by RTA(Rapid Thermal Annealing) at 250-350.deg. C. Surface chemical treatments of p-CdTe thin film improved metal/p-CdTe interface properties and post heat treatment resulted in low contact resistivity to p-CdTe.Of the various contact metal, Cu/Au and Cu show low contact resistance after oven and RTA post-heat treatments, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.6
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• pp.454-459
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• 2020

In this study, a TiO₂/TiO_2-x-based resistance variable memory was fabricated using a DC/RF magnetron sputtering system and ALD. In order to analyze the effect of oxygen plasma treatment on the performance of resistance random access memory (ReRAM), the TiO₂/TiO_2-x-based ReRAM was evaluated by applying RF power to the TiO_2-x oxygen-holding layer at 30, 60, 90, 120, and 150 W, respectively. The ReRAM was fabricated, and the electrical and surface area performances were compared and analyzed. In the case of ReRAM without oxygen plasma treatment, the I-V curve had a hysteresis curve shape, but the width was very small, with a relatively high surface roughness of the oxygen-retaining layer. However, in the case of oxygen plasma treatment, the HRS/LRS ratio for the I-V curve improved as the applied RF power increased; stable improvement was also noted in the surface roughness of the oxygen-retaining layer. It was confirmed that the low voltage drive was not smooth due to charge trapping in the oxygen diffusion barrier layer owing to the high intensity ReRAM applied with an RF power of approximately 150 W.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.600-606
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• 2010

Purpose: Although traditional and current treatment strategies may demonstrate success, persistence or recurrence of difficult-to-heal wounds remain significant problems. A novel product, Hyalomatrix$^{(R)}$ (Fidia Advanced Biopolymer, Abano Terme, Italy) is a bilayer of an benzyl esterified hyaluronan scaffold beneath a silicone membrane. The scaffold delivers hyaluronan to the wound, and the silicone membrane acts as a temporary epidermal barrier. We present the results obtained with Hyalomatrix$^{(R)}$ in the treatment of difficult-to-heal wounds. Methods: From November, 2008 to March, 2010, Hyalomatrix$^{(R)}$ has been used on total 10 patients with wounds that were expected difficult to heal with traditional and other current strategies. After average 37.4 days from development of wounds, Hyalomatrix$^{(R)}$ was applied after wound debridement. On the average, Hyalomatrix$^{(R)}$ application period was 17.6 days. After average 16.5 days from removal of Hyalomatrix$^{(R)}$, skin grafts was performed. Results: In all cases, regeneration of fibrous granulation tissues and edge re-epithelization were present after the application of the Hyalomatrix$^{(R)}$. And all of the previous inflammatory signs were reduced. After skin grafts, no adverse reactions were recorded in 9 cases. But in one case, postoperative wound infection occured due to a lack of efficient fibrous tissues. In this model, the Hyalomatrix$^{(R)}$ acts as a hyaluronan delivery system and a barrier from the external environments. In tissue repair processes, the hyaluronan performs to facilitate the entry of a large number of cells into the wounds, to orientate the deposition of extracellular matrix fibrous components and to change the microenvironment of difficult-to-heal wounds. Conclusion: Our study suggests that Hyalomatrix$^{(R)}$ could be a good and feasible approach for difficult-to-heal wounds. The Hyalomatrix$^{(R)}$ improves microenvironments of difficult-to-heal wounds, reduces infection rates and physical stimulus despite of aggravating factors.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7539-7545
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• 2014

Background: It has been proved that participating in exercise improves colorectal cancer patients' prognosis. This study is to identify barriers to exercise in Korean colorectal cancer patients and survivors. Materials and Methods: A total of 427 colorectal cancer patients and survivors from different stages and medical status completed a self-administered questionnaire that surveyed their barriers to exercise and exercise participation. Results: The greatest perceived exercise barriers for the sampled population as a whole were fatigue, low level of physical fitness, and poor health. Those under 60-years old reported lack of time (p=0.008), whereas those over 60 reported low level of physical fitness (p=0.014) as greater exercise barriers than their counterparts. Women reported fatigue as a greater barrier than men (p<0.001). Those who were receiving treatment rated poor health (p=0.0005) and cancer-related factors as greater exercise barriers compared to those who were not receiving treatment. A multivariate model found that other demographic and medical status were not potential factors that may affect exercise participation. Further, for those who were not participating in physical activity, tendency to be physically inactive (p<0.001) and lack of exercise skill (p<0.001) were highly significant barriers, compared to those who were participating in physical activity. Also, for those who were not meeting ACSM guidelines, cancer-related exercise barriers were additionally reported (p<0.001), compared to those who were. Conclusions: Our study suggests that fatigue, low level of physical fitness, and poor health are most reported exercise barriers for Korean colorectal cancer survivors and there are differences in exercise barriers by age, sex, treatment status, and physical activity level. Therefore, support for cancer patients should be provided considering these variables to increase exercise participation.