• Journal of Korean Neurosurgical Society
• /
• v.67 no.5
• /
• pp.521-530
• /
• 2024

Objective : Dexpanthenol (DXP), which has known neuroprotective effects, has been shown to be beneficial in various experimental models and ischaemic diseases. The aim of this study was to investigate the possible neuroprotective effects of DXP in a traumatic brain injury (TBI) model. Methods : Thirty-six Wistar-Albino female rats, approximately 6 months old, weighing 220-285 g were used. All rats were subjected to closed head trauma by dropping a weight of 350 g on the parietal region from a height of 50 cm at an angle of 180 degrees in the prepared head trauma model setup. The rats were divided into four groups as control (group 1), trauma (group 2), trauma + DXP (group 3), and DXP (group 4). In group 3, DXP was administered intraperitoneally at a dose of 500 mg/kg for six times at 30 minutes, 6, 12, 24, 36, and 48 hours. In group 4, DXP was administered intraperitoneally simultaneously with group 3 without causing head trauma. Blood samples were taken from all rats 72 hours later for biochemical examination. After blood samples were taken, rats were decapitated under general anaesthesia. Cerebral tissue samples were taken from decapitated rats for immunohistochemical and histopathological examination. Results : Cytokine markers were found to be increased in posttraumatic brain tissue. Malondialdehyde and glutathione reductase levels were lower in group 3 compared to group 2. In addition, superoxide dismutase, glutathione peroxidase and catalase levels were significantly higher in group 3 compared to group 2. In histological evaluation, congestion in the piamater layer, cell infiltration, vascular congestion, hemorrhage and neuronal degeneration were significantly decreased in group 3 compared to group 2. DXP seems to be beneficial in neurological recovery in terms of histological and oxidative changes after head trauma in rats. Conclusion : DXP should be further evaluated for its possible therapeutic effect in TBI.

• Journal of Korea Foresty Energy
• /
• v.21 no.2
• /
• pp.25-33
• /
• 2002

One of the critical problems to preserve books and documents in libraries and archives is the deterioration. Some of previous results showed that the major cause of paper deterioration was the acid-catalyzed hydrolysis of the cellulose in paper fibres and aging rate of acidic paper was faster than that of alkaline paper. Therefore, It is necessary to remove the acid in the paper for reducing the rate of paper deterioration. It has been reported to extend the useful life of acidic paper by three to five times. Recently, It has been recognized the need for an effective method of deacidifying large quantities of books and document. However, in the previous many reports little attention was paid to the effect of paper additives. In this paper, We carried out experiment about the effect of additives on paper aging and the effect of deacidification by the gaseous ethanolamines (monoehtanolamine, diethanolamine, triehtanolamine). In result, it was found that the strength of aging was in the order of the alum＋rosin＞alum ＞AKD＞ control and the rate of deacidification was in the order of the monoethanolamine＞diethanolamine＞triethanolamine. The treatment with the gaseous ethanolamines caused decreasing of brightness and dropping of fold endurances. However, deacidification by combination treatment of the various gaseous ehtnaolamines prevented from decreasing of brightness and dropping of folding endurances.

• Journal of Bio-Environment Control
• /
• v.8 no.4
• /
• pp.257-264
• /
• 1999

The trickling system for automatic and individual watering were made with Bunchungto, Ongito and Backjato. The thickness of ceramics were 1.0, 1.5, 2.0, 2.5 and 3.0mm. And they were fired in a muffle furnace at five different temperatures between 500 and 900'E during 12 hours. The upper plastic parts of sensor consisted of five elements made by steel mold. With the photo fiber sensor attached to datalogger, an accumulated amount of drops for every 10 minutes were recorded. The porosity is higher in the order of Bunchungto, Backjato and Ongito; also, as the firing temperature is higher and the thickness is thicker, the porosity is higher. The ceramic sensors consisted of $SiO_2$ of 54.17~71.62wt.%, A1$_2$ $O_3$ of 15.42~33.79wt.% and the rest of 10wt.%, those were Fe$_2$ $O_3$, CaO, MgO, Na$_2$O, $K_2$O, Ti $O_2$, P$_2$ $O_{5}$. The pattern of dropping were changed according to the variety, thickness and firing temperature of ceramics. As the ceramics were made thicker, the fluctuation of dropping became more rapid, but it did not regularly work at 1mm thickness. As the firing temperature of ceramics became higher, the fluctuation of dropped amount became more rapid.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.1
• /
• pp.19-29
• /
• 2022

The result of a questionnaire survey conducted on fishermen using coastal fish traps shows that fall accidents during trap dropping and pulling constitute the highest proportion of accidents at 42.1 %, whereas slipping accidents on the deck or stricture accidents to the body due to the trap winding device constitute 21.1 % each. In addition, 53.2 % of all surveyed subjects responded that trap pulling is the most dangerous task, followed by fish sorting 33.8 %, and trap dropping 9.1 %. As for the main items requested by fishermen for improving the trap winding device, 36.8 % indicated a method to easily lift the trap from the water to the work deck, and 31.6 % indicated a method to overcome the rope tension and prevent slip when pulling the trap to reduce the accidents. The small trap fishing vessel winding device proposed herein can increase the winding force by strengthening the rope contact area and friction coefficient via an appropriate contact angle between the driving roller of the winding device and the rope. When the contact angles between the driving roller and the rope are 1°, 5°, 9°, 14° and 19°, the rope tension showed a difference according to each contact angle. When the contact angle is 9°, the rope tension is the highest at 392.62 kgf. Based on these experimental results, a prototype winding device is manufactured, and 25 traps are installed on a rope with a total length of 100 m at 4 m intervals in the sea, and then the rope tension is measured during trap pulling. As a result, the rope tension increases rapidly at the initial stage of trap pulling and shows the highest value of 31.89 kgf, which subsequently decreases significantly. Therefore, it is appropriate to design the winding force of a small trap fishing vessel winding device based on the maximum tension value of the rope specified at the beginning of the trap pulling operation.

• The Journal of Korean Society for Radiation Therapy
• /
• v.24 no.2
• /
• pp.95-106
• /
• 2012

Purpose: The objective of this study was to investigate the usefulness of an IMRT treatment plan according to whether there was a shell-type pseudo target during radiation therapy for patients in Stage III or IV of non-small cell lung cancer (NSCLC). Materials and Methods: After setting an IMRT (Intensity-Modulated Radiation Therapy, IMRT) plan for when there was a shell-type pseudo target (SPT) and when there was none (WSPT) with 22 patients in Stage III or IV of NSCLC, the investigator analyzed dose-volume histograms (DVHs) and made assessment with dosimetric comparisons such as homogeneity index (HI) inside the tumor target, conformity index (CI) of the tumor target, spinal cord maximum dose, Esophagus $V_{50%}$, mean lung dose (MLD), and $V_{40%}$, $V_{30%}$, $V_{20%}$, $V_{10%}$, $V_{5%}$. Results: The mean CI of WSPT and SPT was $1.22{\pm}0.04$ and $1.16{\pm}0.032$ ($.000^*$), respectively, and the mean HI of WSPT and SPT was $1.06{\pm}0.015$ and $1.07{\pm}0.014$ ($.000^*$), respectively. In SPT, the mean of each CI difference decreased by $-5.16{\pm}2.54%$, while HI increased by average $0.81{\pm}0.47%$. Esophagus $V_{50%}$ recorded $14.54{\pm}12.01%$ (WSPT) and $12.14{\pm}11.09%$ ($.000^*$, SPT) with the mean of SPT differences dropping by $-26.37{\pm}25.05%$. Mean spinal cord maximum dose was $3,898.44{\pm}1,075.0$ cGy (WSPT) and $3,810.8{\pm}1,134.9$ cGy ($.004^*$, SPT) with SPT dropping by average $-3.36{\pm}5.81%$. As for lung $V_{X%}$, the mean of $V_{5%}$ and $V_{10%}$ differences was $-1.62{\pm}2.29%$ ($.006^*$) and $-1.98{\pm}5.02%$ ($.005^*$), respectively with SPT making a decrease. The mean of V20%, V30%, and V40% differences was $-3.51{\pm}3.07%$ ($.000^*$), $-4.84{\pm}6.01%$ ($.000^*$), and $-6.16{\pm}8.46%$ ($.001^*$), respectively, with SPT making a decrease with statistical significance. In MLD assessment, SPT also dropped by average $-2.83{\pm}2.41%$ ($.000^*$). Those results show that SPT allows for mean 169 cGy (Max: 547 cGy, Min: 6.4 cGy) prescription dose. Conclusion: An IMRT treatment plan with SPT during radiation therapy for patients in Stage III or IV of NSCLC will help to reduce the risk of lung toxicity and radiation-induced pneumonia by cutting down radiation doses entering the normal lung, reduce the local control failure rate during radiation therapy due to increasing prescription doses to a certain degree, and increase treatment effects.

• Archives of Pharmacal Research
• /
• v.21 no.6
• /
• pp.645-650
• /
• 1998

The dual drug-loaded alginate beads simultaneously containing drug in inner and outer layers were prepared by dropping plain (single-layered) alginate beads into $CaCl_2$ solution. The release characteristics were evaluated in simulated gastric fluid for 2 h followed by intestinal fluids thereafter for 12 h. The surface morphology and cross section of dual drug-loaded alginate beads was also investigated using scanning electron microscope (SEM). The poorlv water-soluble ibuprofen was chosen as a model drug. The surface of single-layered and dual drug-loaded alginate beads showed very crude and roughness, showing aggregated particles, surface cracks and rough crystals. The thickness of dual drug-loaded alginate beads surrounded by outer layer was ranged from about 57 to 329mcm. The distinct chasm between inner and outer layers was also observed. In case of single-layered alginate bead, the drug was not released in gastric fluid but was largely released in intestinal fluid. However, the release rate decreased as the reinforcing $Eudragit^{\circledR}$ polymer contents increased. When the plasticizers were added into polymer, the release rate largely decreased. The release rate of dual drug-loaded alginate beads was stable in gastric fluid for 2 h but largely increased when switched in intestinal fluid. The drug linearly released for 4 h followed by another linear release thereafter, showing a distinct biphasic release characteristics. There was a difference in the release profiles between single-layered and dual drug-loaded alginate beads due to their structural shape. However, this biphasic release profiles were modified by varying formulation compositions of inner and outer layer of alginate beads. The release rate of dual drug-loaded alginate beads slightly decreased when the outer layer was reinforced with $Eudragit^{\circledR}$ RS1OO polymers. In case of dual drug-loaded alginate beads with polymer-reinforced outer layer only, the initial amount of druc released was low but the initial release rate (slope) was higher due to more swellable inner cores when compared to polymer-reinforced inner cores. The current dual drug-loaded alginate beads may be used to deliver the drugs in a time dependent manner.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.43 no.5 s.347
• /
• pp.84-93
• /
• 2006

Ethernet-PON is an emerging access network technology that provides a low-cost method of deploying optical access lines between OLT and ONUs. It has a point-to-multipoint and multipoint-to-point architecture in downstream and upstream direction, respectively. Therefore, downstream packets are broadcast from an OLT toward all ONUs sithout collision. On the other hand, since alt ONUs share a common channel, the collision may be occurred for the upstream transmission. Therefore, earlier efforts on Ethernet-PON have been concentrated on an upstream MAC protocol to avoid collision. But it is needed to control downstream traffic in practical access network, where the network provider limits available bandwidth according to the number of users. In this paper, we propose a traffic control scheme for supporting the fairness of the downstream bandwidth. The objective of this algorithm is to guarantee the fairness of ONUs while maintaining good performance. In order to do this, we define the service probability that considers the past traffic information for downstream, the number of tokens and the relative size of negotiated bandwidth. We develop the simulation model for Ethernet-PON to evaluate the rate-limiting algorithm by using AWESIM. Some results are evaluated and analyzed in terms of defined fairness factor, delay and dropping rate under various scenario.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.15 no.1
• /
• pp.39-44
• /
• 2005

A sheet type of green body was made with the mixture of 60 wt% red clay, 20 wt% fly ash, and 20 wt% stone sludge. Indentations were made on the surfaces of sheets to investigate fracture rate of 1 to 5 mm artificial light-weight aggregates by various drying, breaking, and forming methods. Drying methods of green bodies were natural, electric oven, microwave, and fast drying by torch. Breaking methods of green bodies were ballmill Ⅰ, ballmill Ⅱ, free dropping in the box, and mechanical breaking with roller mill. The depth and width of indent on the surface of the sheet were varied and the thickness of green bodies was also changed to investigate effects of indentation on fracture rates. The highest fracture rate of 42 % among the various drying methods was obtained by microwave drying for 210 sec and the highest fracture rate of 65 % among the various breaking method was obtained by ballmill Ⅱ method. In forming method, an yield of larger aggregates than Ф = 5 mm decreased and that of smaller aggregates than Ф = 5 mm in creased with increasing depth of indentation (only in 3 mm thick green body)and with increasing thickness of green body. The size of aggregates was most homogeneous (by judging from the measurement of aspect ratio of 1 to 5 mm aggregates.) when 3 mm thick green body was rapidly dried by torch and was broken by ballmill Ⅱ method.

• Journal of Digital Convergence
• /
• v.15 no.11
• /
• pp.425-432
• /
• 2017

The current recommendation systems have problems including the difficulty of figuring out whether they recommend items that actual users have preference for or have simple interest in, the scarcity of data to recommend proper items due to the extremely small number of users, and the cold-start issue of the dropping system performance to recommend items that can satisfy users according to the influx of new users. In an effort to solve these problems, this study implemented a movie recommendation system to ensure user satisfaction by using the Fuzzy-Analytic Hierarchy Process, which can reflect uncertain situations and problems, and the data partition algorithm to group similar items among the given ones. The data of a survey on movie preference with 61 users was applied to the system, and the results show that it solved the data scarcity problem based on the Fuzzy-AHP and recommended items fit for a user with the data partition algorithm even with the influx of new users. It is thought that research on the density-based clustering will be needed to filter out future noise data or outlier data.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.21 no.2
• /
• pp.55-60
• /
• 2015

Packaging of export cut lilies reduces physical damage during distribution like dropping, shock, vibration, compression and serves to protect from necrosis, microbial contamination and decomposition. Study on which packaging materials must be selected is necessary because it serves to direct effect maintaining quality and the degree of freshness. newspaper, perforated OPP film, Oriented Nylon film (ON), punched OPP film, OPP films are used in this study. Plant senescence of lilies was happened rapidly during storage at $25^{\circ}C$ rather than at $5^{\circ}C$. Also, water absorption, fresh weight at during storage $25^{\circ}C$ rather than at $5^{\circ}C$ In addition, fresh weight of lilies storage at $25^{\circ}C$ appears higher than at $5^{\circ}C$ all of the packaging materials except OPP because water absorption of lily storage at $5^{\circ}C$ appears higher than at $25^{\circ}C$, thereby suppressing the fresh weight reducing Also, effect on biological activity of lilies from shape of packaging material appears higher during storage at $5^{\circ}C$ than at $25^{\circ}C$. Compared with each packaging materials, newspaper packaging is the smallest effect on changes in biological activity of cut lilies during storage. Thus, the results demonstrate that flowering date are affected mainly by the storage temperature rather than packaging materials.