• Resources Recycling
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• v.28 no.4
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• pp.30-36
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• 2019

In this study, Li powder was recovered from the by-product of LNO ($Li_2NiO_2$) process, which is the positive electrode active material of waste lithium ion battery, through the $CO_2$ thermal reaction process. In the process of recovering Li powder, the $CO_2$ injection amount is 300 cc/min. The $Li_2NiO_2$ award was phase-separated into the $Li_2CO_3$ phase and the NiO phase by holding at $600^{\circ}C$ for 1 min. After this, the collected sample:distilled water = 1:50 weight ratio, and after leaching, the solution was subjected to vacuum filtration to recover $Li_2CO_3$ from the solution, and the NiO powder was recovered. In order to increase the purity of Ni, it was maintained in $H_2$ atmosphere for 3 hours to reduce NiO to Ni. Through the above-mentioned steps, the purity of Li was 2290 ppm and the recovery was 92.74% from the solution, and Ni was finally produced 90.1% purity, 92.6% recovery.

• Biomolecules & Therapeutics
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• v.27 no.4
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• pp.414-422
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• 2019

There is accumulating evidence that microRNAs are emerging as pivotal regulators in the development and progression of neuropathic pain. MicroRNA-15a/16 (miR-15a/16) have been reported to play an important role in various diseases and inflammation response processes. However, whether miR-15a/16 participates in the regulation of neuroinflammation and neuropathic pain development remains unknown. In this study, we established a mouse model of neuropathic pain by chronic constriction injury (CCI) of the sciatic nerves. Our results showed that both miR-15a and miR-16 expression was significantly upregulated in the spinal cord of CCI rats. Downregulation of the expression of miR-15a and miR-16 by intrathecal injection of a specific inhibitor significantly attenuated the mechanical allodynia and thermal hyperalgesia of CCI rats. Furthermore, inhibition of miR-15a and miR-16 downregulated the expression of interleukin-$1{\beta}$ and tumor-necrosis factor-${\alpha}$ in the spinal cord of CCI rats. Bioinformatic analysis predicted that G protein-coupled receptor kinase 2 (GRK2), an important regulator in neuropathic pain and inflammation, was a potential target gene of miR-15a and miR-16. Inhibition of miR-15a and miR-16 markedly increased the expression of GRK2 while downregulating the activation of p38 mitogen-activated protein kinase and $NF-{\kappa}B$ in CCI rats. Notably, the silencing of GRK2 significantly reversed the inhibitory effects of miR-15a/16 inhibition in neuropathic pain. In conclusion, our results suggest that inhibition of miR-15a/16 expression alleviates neuropathic pain development by targeting GRK2. These findings provide novel insights into the molecular pathogenesis of neuropathic pain and suggest potential therapeutic targets for preventing neuropathic pain development.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.8
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• pp.1095-1103
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• 2019

Objective: Among stress responses, the unfolded protein response (UPR) is a well-known mechanism related to endoplasmic reticulum (ER) stress. ER stress is induced by a variety of external and environmental factors such as starvation, ischemia, hypoxia, oxidative stress, and heat stress. Inositol requiring enzyme $1{\alpha}$ ($IRE1{\alpha}$)-X-box protein 1 (XBP1) is the most conserved pathway involved in the UPR and is the main component that mediates $IRE1{\alpha}$ signalling to downstream ER-associated degradation (ERAD)- or UPR-related genes. XBP1 is a transcription factor synthesised via a novel mechanism called 'frame switch splicing', and this process has not yet been studied in the horse XBP1 gene. Therefore, the aim of this study was to confirm the frame switch splicing of horse XBP1 and characterise its dynamics using Thoroughbred muscle cells exposed to heat stress. Methods: Primary horse muscle cells were used to investigate heat stress-induced frame switch splicing of horse XBP1. Frame switch splicing was confirmed by sequencing analysis. XBP1 amino acid sequences and promoter sequences of various species were aligned to confirm the sequence homology and to find conserved cis-acting elements, respectively. The expression of the potential XBP1 downstream genes were analysed by quantitative real-time polymerase chain reaction. Results: We confirmed that splicing of horse XBP1 mRNA was affected by the duration of thermal stress. Twenty-six nucleotides in the mRNA of XBP1 were deleted after heat stress. The protein sequence and the cis-regulatory elements on the promoter of horse XBP1 are highly conserved among the mammals. Induction of putative downstream genes of horse XBP1 was dependent on the duration of heat stress. We confirmed that both the mechanisms of XBP1 frame switch splicing and various binding elements found in downstream gene promoters are highly evolutionarily conserved. Conclusion: The frame switch splicing of horse XBP1 and its dynamics were highly conserved among species. These results facilitate studies of ER-stress in horse.

• Analytical Science and Technology
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• v.22 no.3
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• pp.191-200
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• 2009

The aim of this study was to evaluate and establish of emission test method for liquid phase building materials such as paint, adhesive, sealant by emission cell. A small-scale emission chamber and emission cell were used to evaluate emission of TVOC from paint, adhesive, sealant. The quantity of TVOC emission were measured by a gas chromatography/mass spectrometry (GC/MS). Background concentration of TVOC was below $10{\mu}g/m^3$ in the emission chamber and cell. Air tightness and recovery in chamber and cell showed good results. The recovery of thermal desorber for toluene and n-dodecane were about 120%. The repeatability of response factor and retention time in GC/MS below 30%. The method detection limit of VOCs ranged 0.04~8.82 ng. The concentration of TVOC emission using emission cell was 1.35~1.41 times higher than emission chamber. The correlation of TVOC emission using chamber and cell method was significantly high (r=0.91~0.97).

• Tunnel and Underground Space
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• v.33 no.5
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• pp.312-338
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• 2023

The underground disposal facility for spent nuclear fuel demands a specialized design, distinct from conventional practices, to ensure long-term thermal, mechanical, and hydraulic integrity, preventing the release of radioactive isotopes from high-temperature spent nuclear fuel. SKB has established design criteria for such facilities and executed practical design implementations for Forsmark. Moreover, in response to subsurface uncertainty, SKB has proposed an empirical approach involving monitoring and adaptive design modifications, alongside stepwise development. SKB has further introduced a unique support system, categorizing ground types and behaviors and aligning them with corresponding support types to confirm safety through comparative analyses against existing systems. POSIVA has pursued a comparable approach, developing a support system for Onkalo while accounting for distinct geological characteristics compared to Forsmark. This demonstrates the potential for domestic implementation of spent nuclear fuel disposal facility designs and the establishment of a support system adapted to national attributes.

• Journal of Adhesion and Interface
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• v.25 no.1
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• pp.169-274
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• 2024

Recent attention has been drawn to materials that undergo reversible expansion and contraction in response to external stimuli, leading to morphological changes. These materials hold potential applications in various fields including soft robotics, sensors, and artificial muscles. In this study, a novel material capable of responding to high temperatures for protection or encapsulation is proposed. To achieve this, liquid crystal elastomer (LCE) with nematic-isotropic transition properties and polyimide (PI) with high mechanical strength and thermal stability were utilized. To utilize a solution process, a dope solution was synthesized and introduced into micro-printing techniques to develop a two-dimensional pattern of LCE/PI bilayer structures with sub-millimeter widths. The honeycomb-patterned LCE/PI bilayer mesh combined the mechanical strength of PI with the high-temperature contraction behavior of LCE, and selective printing of LCE facilitated deformation in desired directions at high temperatures. Consequently, the functionality of selectively and reversibly encapsulating specific high-temperature materials was achieved. This study suggests potential applications in various actuator fields where functionalities can be implemented across different temperature ranges without the need for electrical energy input, contingent upon molecular changes in LCE.

• Korean Journal of Remote Sensing
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• v.33 no.5_1
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• pp.587-598
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• 2017

Volcanic ash is a fine particle smaller than 2 mm in diameters. It falls after the volcanic eruption and causes various damages to transportation, manufacturing industry and respiration of living things. Therefore diffusion information of volcanic ash is highly significant for preventing the damages from it. It is advantageous to utilize satellites for observing the widely diffusing volcanic ash. In this study volcanic ash diffusion information about two eruptions of Mt. Sakurajima were calculated using the geostationary satellite, Communication, Ocean and Meteorological Satellite (COMS) Meteorological Imager (MI) and polar-orbiting satellite, Landsat-8 Operational Land Imager (OLI) and the Thermal InfraRed Sensor (TIRS). The direction and velocity of volcanic ash diffusion were analyzed by extracting the volcanic ash pixels from COMS-MI images and the height was retrieved by adjusting the shadow method to Landsat-8 images. In comparison between the results of this study and those of Volcanic Ash Advisories center (VAAC), the volcanic ash tend to diffuse the same direction in both case. However, the diffusion velocity was about four times slower than VAAC information. Moreover, VAAC only provide an ash height while our study produced a variety of height information with respect to ash diffusion. The reason for different results is measured location. In case of VAAC, they produced approximate ash information around volcano crater to rapid response, while we conducted an analysis of the ash diffusion whole area using ash observed images. It is important to measure ash diffusion when large-scale eruption occurs around the Korean peninsula. In this study, it can be used to produce various ash information about the ash diffusion area using different characteristics satellite images.

• Restorative Dentistry and Endodontics
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• v.24 no.4
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• pp.560-569
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• 1999

Blood supply rather than nerve supply implies pulp vitality. To evaluate pulp vitality clinically, electric pulp test and thermal test which are based on sensory nerve response have been used in addition to many auxiliary data such as past dental history, visual inspection, radiographic examination, percussion, palpation and transillumination test. However, reactivity of the nerves to the stimulation is not synonymous with normalcy. Therefore measurement of pulpal blood flow using a laser Doppler flowmeter became a new trial to test the pulp vitality. The purpose of the present study was to evaluate normal pulpal blood flow level of maxillary teeth in adult to provide a guideline in determining the vitality of dental pulp. Pulpal blood flow was measured in maxillary central and lateral incisors, canines, first and second premolars and first molars of seventy nine adults of 22 - 30 years old using a laser Doppler flowmeter (PeriFlux 4001, Perimed Co., Stockholm, Sweden, 780 nm infrared laser, 1mW). For directly-made splints, silicone rubber impressions were taken directly from the mouth. For indirectly-made splints, alginate impressions were taken from the mouth and stone cast were made. After making depressions on the buccal surfaces of the cast teeth to indicate the hole positions, second impressions with vinyl polysyloxane putty were taken from the cast. Holes for the laser probes were made at the putty impressions 4mm above the gingival level. Laser probe (PF416 dental probe, 1.5mm) was inserted in the prepared hole and the splint was set in the mouth. After 10 minutes of patient relaxing, pulpal blood flow was recorded for 5 minutes on each tooth. The recorded flow was saved in the computer and calculated with a software 'Perisoft' version 5.1. Pulpal blood flow was also recorded in six teeth of five individuals with no response to electric pulp test and cold test, with periapical radiolucency, or with history of root canal treatment to compare with nonvital teeth. The difference between the mean flow values of each group of teeth were analyzed using one-way ANOVA and Duncan's Multiple Range test. The results were as follows: 1. The average pulpal blood flow values of all the tested teeth of each location were between 9 - 16 Perfusion Unit. Pulpal blood flow value was highest in maxillary lateral incisors, followed by first premolars, second premolars, canines, central incisors, and then first molars (p<0.01). 2. In six anterior teeth, indirectly-made splint group showed higher pulpal blood flow values than directly-made splint group (p<0.01). In posterior teeth, however, there was no significant flow value difference between directly-made splint group and indirectly-made splint one (p>0.05). 3. Teeth with vital pulps showed higher signal values than teeth with nonvital pulps (p<0.01), and the flow photographs showed heartbeat-synchronous fluctuations and vasomotions, while those were absent in non vital tooth.

• Journal of the Korean earth science society
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• v.21 no.6
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• pp.703-718
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• 2000

In order to investigate interannual variation of total ozone and reflectivity over the globe, Nimbus-7/TOMS data were used on the monthly mean and its anomaly for the period of 1979-92. This study also examined MSU channel 4(Ch4; lower-stratosphere) brightness temperature data and two model reanalyses of NCEP and GEOS to compare the ozone variation with atmospheric thermal condition. In addition, the MSU channel 1(Ch1 ; lower-troposphere) brightness temperature was used to compare with the reflectivity. The ozone showed strong annual cycle with downward trend(-6.3${\pm}$0.6 DU/decade) over the globe, and more distinct response to volcanic eruption than El Ni${\tilde{n}$o. The relationship between total ozone and MSU Ch4 observation, and between the ozone and model reanalyses of lower stratosphere temperature showed positive correlation(0.2-0.7) during the period of 1980-92. Reflectivity increased interannually by 0.2${\pm}$0.06%/decade over the globe during the above period and reflected El Ni${\tilde{n}$o(1982-83, 1991-92) well. Its variability in annual cycle was remarkably smaller in tropics than in higher latitudes. This is inferred due to cloud suppression and tropical upwelling regions. Reflectivity correlated negatively(-0.9) to the Ch1 temperature over the globe, but positively(0.2) over tropical ocean. The positive value over the ocean results from the effect of microwave emissivity which increases the Ch1 temperature with enhanced hydrometeor activity. Significant correlations between total ozone and the Ch4 temperature, and between reflectivity and the Ch1 Suggest that the TOMS data may use valuably to better understand the feedback mechanism of climate change.

• The Korean Journal of Ecology
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• v.25 no.3 s.107
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• pp.163-170
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• 2002

In order to analyze the life cycle of A. artemisiifolia var. elatior dormancy and some environmental factors inducing germination of the seeds were examined. The results were as follows : Dormancy of fertile seeds was broken in part within a month after seed collection in case of adequate moisture and alternating temperature was also effective in breaking dormancy. The temperature range, which allow germination was $12^{\circ}C{\sim}32^{\circ}C$. Optimum temperature for germination was $24^{\circ}C$. The seed of A. artemisiifolia var. elatior was light-independent. The difference of storage period appeared to have no particular effect on the viability of seeds at any time during the 9-month storage period. In the increasing temperature(IT) regime, A. artemisiifolia var. elatior seeds started to germinate at $16^{\circ}C$, showing the higher temperature the greater germination rate : the final germination percentage was 99.34%. On the other hand, in the decresing temperature(DT) regime, seeds began to germinate at $20^{\circ}C$ with the 1.34% germination. An induced dormancy occurred at $12^{\circ}C$ making the 5.34% final germination in the DT regime. Low temperature was more effective to break dormancy than higher temperature. Seeds of A. artemisiifolia var. elatior seems to be germinated in mid to late autumn or germination delayed until following spring. The above results suggest these variation of germination response in diverse environmental factors seems to be a physiological strategy to maintain their existence and to reproduce in the extreme thermal variation.