• Journal of the Korean Society for Precision Engineering
• /
• v.28 no.3
• /
• pp.383-388
• /
• 2011

The cold hollow cathode gas ion source is under development for multi aperture focused ion beam (FIB) system. In this paper, we describe the cold hollow cathode ion source design and the general ion source performance using Ar gas. The glow discharge characteristics and the ion beam current density at various operation conditions are investigated. This ion source can generate maximum ion beam current density of approximately 120 mA/$cm^2$ at ion beam potential of 10 kV. In order to effectively transport the energetic ions generated from the ion source to the multi-aperture focused ion beam(FIB) system, the einzel lens system for ion beam focusing is designed and evaluated. The ions ejected from the ion source can be forced to move near parallel to the beam axis by adjusting the potentials of the einzel lenses.

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

• Journal of Biomedical Engineering Research
• /
• v.44 no.4
• /
• pp.275-283
• /
• 2023

The demand for skincare has increased due to the end of the COVID-19 pandemic, leading to a focus on skincare devices and technologies designed to improve the delivery of cosmetics. Among these technologies, skincare medical devices that utilize plasma therapy (Plasma) and sonophoresis (Sono) are commonly used in dermatology clinics. However, there is still a lack of quantitative analysis for transdermal absorption effects of Plasma and Sono skincare medical devices. In this study, we quantified enhanced transdermal absorption effects of Plasma and Sono devices through in-silico and ex-vivo studies. The Sono treatment demonstrated an increased transdermal absorption effect, showing a 10~13% difference in penetration compared to the control group in the in-silico experiment, and 159% and 184% increase in the ex-vivo experiment. The Plasma treatment revealed increased transdermal absorption effects, with a 1.0~2.5% penetration difference in the in-silico experiment, and a 124% increase in the ex-vivo experiment compared to the control group. We also observed a synergistic effect from the combined treatment of Plasma and Sono, as indicated by the highest increases of 197% and 242% in penetration. Furthermore, we have determined the optimal device settings and treatment conditions for Plasma-Sono skincare medical devices. Notably, higher on/off durations (Intensity levels) and longer Sono treatments resulted in greater transdermal absorption effects.

• Journal of Animal Science and Technology
• /
• v.65 no.5
• /
• pp.1094-1104
• /
• 2023

Aggression in horses may cause serious accidents during riding and non-riding activities. Hence, predicting the temperament of horses is essential for selecting suitable horses and ensuring safety during the activity. In certain animals, such as hamsters, plasma melatonin concentrations have been correlated with aggressive behavior. However, whether this relationship applies to horses remains unclear. To address this research gap, this study aimed to evaluate differences in the plasma melatonin concentrations among horses of different breeds, ages, and sexes and examine the correlation between plasma melatonin concentrations and the temperament of the horses, including docility, affinity, dominance, and trainability. Blood samples from 32 horses were collected from the Horse Industry Complex Center of Jeonju Kijeon College. The docility, affinity, dominance, and trainability of the horses were assessed by three professional trainers who were well-acquainted with the horses. Plasma melatonin concentrations were measured using an enzyme-linked immunosorbent assay. The consequent values were compared between the horses of different breeds, ages, and sexes using a three-way analysis of variance and least significant difference post hoc test. Linear regression analysis was employed to identify the relationship between plasma melatonin concentrations and docility, affinity, dominance, and trainability. The results showed that the plasma melatonin concentrations significantly differed with breeds in Thoroughbred and cold-blooded horses. However, there were no differences in the plasma melatonin concentrations between the horse ages and sexes. Furthermore, plasma melatonin concentrations did not exhibit a significant correlation with the ranking of docility, affinity, dominance, and trainability.

• Natural Product Sciences
• /
• v.28 no.2
• /
• pp.68-74
• /
• 2022

HemoHIM was used as a Korean traditional medicine for anti-inflammatory and antioxidant effects. However, there is no study on the effect of HemoHIM on fatigue. We examined the potential use of HemoHIM to determine whether it can induce anti-fatigue effects. Mice were administered with HemoHIM and VEH for 14 days. On the last day of treatment, mice were subjected to behavioral tests. Subsequently, their plasma and muscle were collected after the treadmill test to measure lactate, lactate dehydrogenase (LDH), ammonia, corticosterone, glycogen, and creatine kinase (CK). We found that HemoHIM moderately increased the running time (s) in the treadmill and mobility duration in the cold swimming tests. In addition, the VEH group showed a significant increase in lactate, LDH, and corticosterone levels in the plasma compared to the group that did not perform the test. However, this was moderately reduced in HemoHIM treatment. Moreover, the HemoHIM-treated group showed significant differences in LDH and glycogen levels, and showed significantly different CK levels in the muscle. HemoHIM is considered to be effective in improving fatigue, given the duration of cold swimming or running time on a treadmill. Also, HemoHIM treatment resulted in reduced concentrations of blood and muscle parameter analysis.

• Natural Product Sciences
• /
• v.9 no.2
• /
• pp.68-72
• /
• 2003

Quercetin and its sugar conjugates are the most abundantly distributed bioflavonoids and represent the largest proportion of flavonols in the plant kingdom. The present study was undertaken to demonstrate the effect of quercetin on the role of reactive oxygen species (ROS) in the development of gastric ulcers in rats. Administration of quercetin in doses of 50, 100 and $200\;mg\;kg^{-1}$ twice daily for 5 days, showed dose dependent significant protection against ethanol (EtOH), aspirin (ASP), cold-restraint stress (CRS) and pylorus ligation (PL) -induced gastric ulcer models and the results were comparable with those elicited by sucralfate. The thiobarbituric acid reactive substances in the stomach mucosa, an index of lipid peroxidation and regulation of plasma corticosterone were significantly increased in CRS-induced gastric ulceration. The queroetin $(100\;mg\;kg^{-1})$ and reduced glutathione effectively inhibited gastric lesions induced by CRS with a significant decrease in the lipid peroxidation and plasma corticosterone. These results indicate that quercetin a bioflavonoid exerts its antiulcer effect in light of free radical scavenging and plasma corticosterone in cold restraint stress ulcers.

• The Bulletin of The Korean Astronomical Society
• /
• v.42 no.1
• /
• pp.40.3-41
• /
• 2017

Korea Astronomy and Space Science Institute The observation of particles and waves using a single satellite inherently suffers from space-time ambiguity. Recently, such ambiguity has often been resolved by multi-satellite observations; however, the inter-satellite distances were generally larger than 100 km. Hence, the ambiguity could be resolved only for large-scale (> 100 km) structures while numerous microscale phenomena have been observed at low altitude satellite orbits. In order to resolve those spatial and temporal variations of the microscale plasma structures on the topside ionosphere, SNIPE mission consisted of four (TBD) nanosatellites (~10 kg) will be launched into a polar orbit at an altitude of 700 km (TBD). Two pairs of satellites will be deployed on orbit and the distances between each satellite will be from 10 to 100 km controlled by a formation flying algorithm. The SNIPE mission is equipped with scientific payloads which can measure the following geophysical parameters: density/temperature of cold ionospheric electrons, energetic (~100 keV) electron flux, and magnetic field vectors. All the payloads will have high temporal resolution (~ 16 Hz (TBD)). This mission is planned to launch in 2020. The SNIPE mission aims to elucidate microscale (100 m-10 km) structures in the topside ionosphere (below altitude of 1,000 km), especially the fine-scale morphology of high-energy electron precipitation, cold plasma density/temperature, field-aligned currents, and electromagnetic waves. Hence, the mission will observe microscale structures of the following phenomena in geospace: high-latitude irregularities, such as polar-cap patches; field-aligned currents in the auroral oval; electro-magnetic ion cyclotron (EMIC) waves; hundreds keV electrons' precipitations, such as electron microbursts; subauroral plasma density troughs; and low-latitude plasma irregularities, such as ionospheric blobs and bubbles. We have developed a 6U nanosatellite bus system as the basic platform for the SNIPE mission. Three basic plasma instruments shall be installed on all of each spacecraft, Particle Detector (PD), Langmuir Probe (LP), and Scientific MAGnetometer (SMAG). In addition we now discuss with NASA and JAXA to collaborate with the other payload opportunities into SNIPE mission.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2004.06a
• /
• pp.32-42
• /
• 2004

Recently, plasma surface-cleaning or surface-etching techniques have been focused in respect of the decontamination of spent or used nuclear parts and equipment. In this study the removal rate of metallic cobalt surface is experimentally investigated via its surface etching rate with a $CF_4-o_2$mixed gas plasma. Experimental results reveal that a mixed etchant gas with about 80% $CF_4$-20% $O_2$ (molar) gives the highest reaction rate and the rate reaches 0.06 ${\mu}m$/min at $380^{\circ}C$ and ion-assisted etching dramatically enhances the surface reaction rate. With a negative 300 V DC bias voltage applied to the substrate, the surface reaction initiation temperature lowers and the rate increases about 20 times at $350^{\circ}C$ and up to 0.43 ${\mu}m$/min at $380^{\circ}C$, respectively. Surface morphology analysis confirms the etching rate measurements. Auger spectrum analysis clearly shows the adsorption of fluorine atoms on the reacted surface. From the current experimental findings and the results discussed in previous studies, mechanistic understanding of the surface reaction, fluorination and/or fluoro-carbonylation reaction, is provided.

• Journal of Astronomy and Space Sciences
• /
• v.39 no.2
• /
• pp.35-42
• /
• 2022

During their respective missions, the spacecraft Voyager and Cassini measured several Saturn magnetosphere parameters at different radial distances. As a result of information gathered throughout the journey, Voyager 1 discovered hot and cold electron distribution components, number density, and energy in the 6-18 Rs range. Observations made by Voyager of intensity fluctuations in the 20-30 keV range show electrons are situated in the resonance spectrum's high energy tail. Plasma waves in the magnetosphere can be used to locate Saturn's inner magnetosphere's plasma clusters, which are controlled by Saturn's spin. Electromagnetic electron cyclotron (EMEC) wave ring distribution function has been investigated. Kinetic and linear approaches have been used to study electromagnetic cyclotron (EMEC) wave propagation. EMEC waves' stability can be assessed by analyzing the dispersion relation's effect on the ring distribution function. The primary goal of this study is to determine the impact of the magnetosphere parameters which is observed by Cassini. The magnetosphere of Saturn has also been observed. When the plasma parameters are increased as the distribution index, the growth/damping rate increases until the magnetic field model affects the magnetic field at equator, as can be seen in the graphs. We discuss the outputs of our model in the context of measurements made in situ by the Cassini spacecraft.

• Journal of Animal Science and Technology
• /
• v.65 no.1
• /
• pp.69-95
• /
• 2023

In order to evaluate the effects of ARG sources (arginine [ARG] and Guanidinoacetic acid [GAA]) and phenylalanine (PHE) supplementation on performance, susceptibility to ascites, intestinal morphology, and nutrient digestibility in the cold-stressed broilers fed a canola meal (CM)-based diet, a 2×2 factorial experiment with four treatments was conducted. The dietary treatments included CM-based diet + 2.57 g/kg ARG, CM-based diet + 2.57 g/kg ARG + 1.5 g/kg PHE, CM-based diet + 1.8 g/kg GAA and CM-based diet + 1.8 g/kg GAA + 1.5 g/kg PHE. The corn-CM diet without supplementation was used as a negative control (NC) group in the fifth treatment that excluded the factorial arrangement. The results showed that adding ARG to diets without PHE supplement increased (p < 0.05) feed intake. Also, birds fed diets containing ARG had higher (p < 0.05) body weight gain (BWG) compared to those fed GAA added diets. Supplementation of PHE improved (p < 0.05) the FCR compared to groups fed diets without added PHE. Further, ARG addition increased (p < 0.05) plasma nitric oxide (NO) concentration, carcass, breast and leg yields, duodenal, jejunal, and ileal villus height (VH) to crypt depth (CD, and dry matter digestibility, while decreasing (p < 0.05) ascites mortality and right ventricle (RV) to total ventricle (TV) ratio compared to GAA added groups. Supplementation of PHE also declined susceptibility to ascites by reducing (p < 0.01) RV to TV ratio while increasing (p < 0.05) plasma NO level. The digestibility of ether extract also increased (p < 0.05) in broilers fed GAA supplemented diets versus those fed ARG added diets. The findings suggested that ARG may improve BWG and lower ascites incidence in broilers fed a diet based on CM under cold stress because of its antihypertensive effects. Moreover, the findings of this study demonstrated the importance of including PHE formulation in ARG-deficient diets to attenuate the adverse effects of cold stress on broilers. It was also concluded that GAA could be efficaciously used in cold-stressed broilers fed an ARG-deficient diet.