• Journal of Korean Neurosurgical Society
• /
• v.63 no.2
• /
• pp.188-201
• /
• 2020

Objective : The purpose of this study was to suggest that computed tomography angiography (CTA) is valuable as the only preliminary examination for mechanical thrombectomy (MT). MT after single examination of CTA including noncontrast computed tomography (NCCT) and maximum intensity projection (MIP) improves door-to-puncture time as well as results in favorable outcomes. Methods : A total of 157 patients who underwent MT at Dong Kang Medical Center from April 2015 to March 2019 were divided into two groups based on the examination performed prior to MT : CTA group who underwent CTA with NCCT and MIP, and NCCT+magnetic resonance image (MRi) group who underwent MRI including perfusion images after NCCT. In the two groups, time to CTA imaging or NCCT+MRi imaging after symptom onset, and time to arterial puncture and reperfusion were characterized as time-related outcomes. The evaluation of vascular recanalization after MT was defined as a modified thrombolysis in cerebral infarction (mTICI) scale. National Institutes of Health Stroke Scale (NIHSS) was assessed at the time of the visit to the emergency room and modified Rankin Scale (mRS) was assessed after 90 days. Results : Typically, there were 34 patients in the CTA group and 33 patients in the NCCT+MRi group. A significantly shorter delay for door-to-puncture time was observed (mean, 86±22.1 vs. 176±47.5 minutes; <0.01). Also, a significantly shorter door-to-imege time in the CTA group was observed (mean, 13±6.8 vs. 93±30.8 minutes; p<0.01). Moreover, a significantly shorter onset-to-puncture time was observed (mean, 195±128.0 vs. 314±157.6 minutes; p<0.01). Reperfusion result of mTICI ≥2b was 100% (34/34) in the CTA group and 94% (31/33) in the NCCT+MRi group, and mTICI 3 in 74% (25/34) in the CTA group and 73% (24/33) in the NCCT+MRi group. Favorable functional outcomes (mRS score ≤2 at 90 days) were 68% (23/34) in the CTA group and 60% (20/33) in the NCCT+MRi group. Conclusion : A single-phase CTA including NCCT and MIP images was performed as a single preliminary examination, which led to a reduction in the time of the procedure and resulted in good results of prognosis. Consequently, it is concluded that this method is of sufficient value as the only preliminary examination for decision making.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.13 no.6
• /
• pp.141-148
• /
• 2003

The self-healing key distribution scheme with revocation capability proposed by Staddon et al. enables a dynamic group of users to establish a group key over an unreliable network, and has the ability to revoke users from and add users to the group while being resistant to collusion attacks. In such a protocol, if some packet gets lost, users ale still capable of recovering the group key using the received packets without requesting additional transmission from the group manager. In this scheme, the storage overhead at each group member is O($m^2$1og p) and the broadcast message size of a group manager is O( ((m$t^2$+mt)log p), where m is the number of sessions, t is the maximum number of colluding group members, and p is a prime number that is large enough to accommodate a cryptographic key. In this paper we describe the more efficient self-healing key distribution scheme with revocation capability, which achieves the same goal with O(mlog p) storage overhead and O(($t^2$+mt)log p) communication overhead. We can reduce storage overhead at each group member and the broadcast message size of the group manager without adding additional computations at user's end and group manager's end.

• Fisheries and Aquatic Sciences
• /
• v.5 no.1
• /
• pp.59-63
• /
• 2002

Swim up fry of the Nile tilapia, Oreochromis niloticus, were fed 0 or 60 mg l7-methyltestos­terone (MT) per kg feed for 30 days. Fish that had been fed 0 or 60 ppm MT for the first 30 days were subsequently fed a commercial diet for 56 weeks to evaluate growth, survival, sex ratio, body composition, gonadosomatic index and the total edible portion. Mean body weight of MT treated group and untreated group were 1.7 g and 1.1 g, respectively at the end of the treatment for 30 days $(P<0.05)$. The experiment was terminated after a total of 60 weeks, the mean body weight of the MT treated population was 1,016 g and that of the untreated population was 762g $(P<0.05)$. However, the final mean body weight of untreated males (l, 086g) was not significantly different from treated males (l,016 g), but the mean body weight of the female group was 512 g. Therefore, the reason for the lower mean body weight of the untreated group was entirely due to stunted females. The percentage fillet yield of MT treated fish$(34.6\%)$ was not significantly different from that of the untreated males $(34.4\%)$, but the untreated females were lower than those of both treated and untreated male groups $(32.4\%)$ (P<0.05). There were no significant differences in the percentage of the all edible portion (AP) between MT treated and untreated males, but females were lower than males. Females are smaller fish in size and the gonads are larger in proportion which were discarded along with the intestine this explains the observed difference. Total biomass of the two groups were 134.8kg and 104.5kg per $m^3$, respectively. The proportion of fish reaching a marketable size of over 800 g in body weight within 14 months were $78\%$ in the MT treated group and $41\%$ in the untreated group.

• Journal of Magnetics
• /
• v.14 no.4
• /
• pp.137-143
• /
• 2009

The convergence behavior of the all-electron full-potential linearized augmented plane-wave (FLAPW) method with the explicit orthogonalization (XO) scheme is tested on ferromagnetic bulk body-centered-cubic Fe. Applying a commonly used criterion relating the plane-wave and angular momentum cutoffs, $l_{max}\;=\;R_{MT}K_{max}$, where $R_{MT}$ is the muffin-tin (MT) sphere radius and $K_{max}$ is the plane-wave cutoff for the basis - the total energy is converged and stable for $K_{max}R_{MT}$ = 10. The total energy convergence dependence on the star-function cutoff, $G_{max}$, is minimal and so a $G_{max}$ of 3$K_{max}$ or a large enough $G_{max}$ is a reasonable choice. We demonstrate that the convergence with respect to $l_{max}$ or a fixed large enough $G_{max}\;and\;K_{max}$ are independent, and that $K_{max}$ provides a better measure of the convergence than $R_{MT}K_{max}$. The dependence of the total energy on $R_{MT}$ is shown to be small if the core states are treated equivalently, and that the XO scheme is able to treat systems with significantly smaller $R_{MT}$ than the standard LAPW method. For converged systems, the calculated lattice parameter, bulk modulus, and magnetic moments are in excellent agreement with the experimental values.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.40 no.5
• /
• pp.637-643
• /
• 1995

TR75, a rice (Oryza sativa L. var. Sasanishikj) mutant resistant to 5-methyltryptophan (5MT) was segregated from the progenies of its initial mutant line, TR1. The 5MT resistance of TR75 was inherited in the M$_{8}$ generations as a single dominant nuclear gene, and was also expressed in callus derived from seeds, roots, and anthers as well as in the seedlings. The callus induced from these organs could grow at 50 mg/1 of 5MT, whereas the growth of wild-type callus was completely inhibited even at 25 mg/1. The seedlings of TR75 did not show resistance to L-azetidine-2-carboxylic acid, S-2-aminoethyl-L-cysteine, p-fluoro-DL-phenylalanine. The content of free amino acids in the TR75 homozygous seeds increased approximately 1.5 to 2.0 fold compared to wild-type seeds. Especially, the contents of tryptophan, phenylalanine and aspartic acid were 5.0, 5.3 and 2.7 times higher than those of wild-type seeds, respectively.y.

• Korean Journal of Environment and Ecology
• /
• v.28 no.1
• /
• pp.33-44
• /
• 2014

The purpose of this study was to provide basic information and investigate a vegetation structure around Tohamsan (Mt.) Wetland. Actual vegetation map was made on the basis of watershed around that. Vegetation structure survey was carried out for 8 representative communities of actual vegetation which were Pinus densifrora community, Quercus variabilis community, Cornus controversa community, Q. serrata community, Q. mongolica-Q. serrata community, Salix koreensis community, Q. mongolica community, Q. variabilis-Q. mongolica-Q. serrata community. Tohamsan (Mt.) Wetland is located on 490m above sea level and the area of watershed was $236,272m^2$. Vegetation type were divided into 16 types, and the ratio of Q. mongolica community was 33.1% ($78,209.2m^2$). In order to turn out the structure of 8 representative communties, 32 plots were set up and unit area of plot was $100m^2$. The estimated age of forest is 30~50-years-old, and in the resutls of soil analysis, acidity was pH 4.89 and organic matter was 4.46%.

• Journal of Korean Society of Forest Science
• /
• v.70 no.1
• /
• pp.17-27
• /
• 1985

Through the study of the physiognomical vegetation, the vertical distribution, the distribution of forest community and the flora of the woody plants on the south facing slope of Mt. Pal-Gong, the results obtained were summarized as follows. The forest of Pinus densiflora was dominant in the region of below 750m above the sea level, the mixed forest of conifer and broad-leaved trees in the region of 750m to 950m and the pure forest of deciduous broad-leaved trees in the region of above 950m. Pinus densiflora and Quercus mongolica were dominant for the upper-story trees, Acer pseudo-sieboldianum and Carpinus laxiflora for the mid-story trees, Lespedeza maximowiczii, Sasa purpurascens, Rhododendron mucronulatum and Rhododendron schlippenbachii for the under-story trees. Among seventeen forest communities, Cephalotaxus koreana, Populus davidiana and Alnus hirsuta var. sibirica were considered remarkable communities on the south facing slope of Mt. Pal-Gong. The woody plants growing on Mt. Pal-Gong are composed of 59 families, 7 subfamilies, 122 genera, 178 species, 29 varieties and 10 formae. Populus davidiana, Alnus hirsuta var. sibirica and Rubus phoenicolasius were collected newly in this study.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.22 no.3
• /
• pp.79-90
• /
• 1994

This survey was ocnducted to investgate changes of the plant community structure from 1972 to 1993 in forest of Mt. Kwanak and thirty-five plots that the size of each plot was 10m${\times}$10m(100㎡) were set up and the vegetation analysis was caried out. By the TWINSPAN analysis, the plant community of survey area were divied into Quercus mongolica, Q. mongolica-Pinus densiflora(1), Q. mongolica-P. densiflora(2), Q. acutissima community. The successional trends of the woody species were seemed to be from P. densiflora, Sorbus alnifolia to Q. mongolica in the canopy layer. But the successional trends in the understory and shrub layer were difficult to suppose. The forest vegetation of Mt. Kwanak from 1972 to 1993 was severely decreased in species number and individuals. The sensitive species for the environmental pollution were selected, and the tolerant plants for the acid soil were increased. In comparision with the DBH class distribution from 1972 to 1993, it shows that the ecological succession has stopped. In the analysis of soil characteristics, soil acidification has taken place over last twenty-two years(from pH=5.40 to pH=4.53). The concentration of K+, Ca++ was severly decreased(from K+=0.60m.e./100g to K+=0.06m.e./100g, from Ca++=3.20m.e./100g to Ca++=0.63m.e./100g), which also could seemed to be cause of plant community decline.

• Archives of Pharmacal Research
• /
• v.19 no.4
• /
• pp.280-285
• /
• 1996

The sustained release dosage form which delivers melatonin (MT) in a circadian fashion over 8 h is of clinical value for those who have disordered circadian rhythms because of its short halflife. The purpose of this study was to evaluate the gelling properties and release characteristics of alginate beads varying multivalent cationic species $(Al^{+++}, \; Ba^{++}, \; Ca^{++}, \; Mg^{++}, \; Fe^{+++}, \; Zn^{++})$. The surface morphologies of Ca- and Ba-alginate beads were also studied using scanning electron microscope (SEM). MT, an indole amide pineal hormone was used as a model drug. The $Ca^{++}, \; Ba^{++}, \; Zn^{++}, \; Al^{++}\; and\; Fe^{+++}\; ions\; except\; Mg^{++}$ induced gelling of sodium alginate. The strength of multivalent cationic alginate beads was as follows: $Al^{+++}\llFe^{+++} the induced hydrogel beads were very fragile and less spherical. Fe-alginate beads were also fragile but stronger compared to Al-alginate beads. Ba-alginate beads had a similar gelling strength but was less spherical when compared to Ca-alginate beads. Zn-alginate beads were weaker than Ca- and Ba-alginate beads. Very crude and rough crystals of Ba- and Ca-alginate beads at higher magnifications were observed. However, the type and shape of rough crystals of Ba- and Ca-alginate beads were quite different. No significant differences in release profiles from MT-loaded multivalent cationic alginate beads were observed in the gastric fluid. Most drugs were continuously released upto 80% for 5 h, mainly governed by the passive diffusion without swelling and disintegrating the alginate beads. In the intestinal fluid, there was a significant difference iq the release profiles of MT-loaded multivalent cationic alginate beads. The release rate of Ca-alginate beads was faster when compared to other multivalent cationic alginate beads and was completed for 3 h. Ba-alginate beads had a very long lag time (7 h) and then rapidly released thereafter. MT was continuously released from Feand Zn-alginate beads with initial burstout release. It is assumed that the different release rofiles of multivalent cationic alginate beads resulted from forces of swelling and disintegration of alginate beads in addition to passive diffusion, depending on types of multivalent ions, gelling strength and drug solubility. It was estimated that 0.2M $CaCl_2$ concentration was optimal in terms of trapping efficiency of MT and gelling strength of Ca-alginate beads. In the gastric fluid, Ca-alginate beads gelled at 0.2 M $CaCl_2$ concentration had higher bead strength, resulting in the most retarded release when compared to other concentrations. In the intestinal fluid, the decreased release of Ca-alginate beads prepared at 0.2 M $CaCl_2$ concentration was also observed. However, release profiles of Ca-alginate beads were quite similar regardless of $CaCl_2$ concentration. Either too low or high $CaCl_2$ concentrations may not be useful for gelling and curing of alginate beads. Optimal $CaCl_2$ concentrations must be decided in terms of trapping efficiency and release and profiles of drug followed by curing time and gelling strength of alginate beads.

• Korean Journal of Environment and Ecology
• /
• v.11 no.3
• /
• pp.366-386
• /
• 1997

This study was conducted to investigate the flora of Mt. Myongji and also to find the distribution characteristecs of rare and endangered plants in this mountain. Field surveys were carride out 21 times from 1991 to 1997. Main results obtained from this study were as follows; 1. Mt. Myougji was covered with Pinus koraiensis and Sarix leptolepis stands at the altitude lower than 600m, and deciduous forests which were consisted of Quercus mongolica, Carpinus sp., Acer sp., Cornus sp., Fracinus sp., etc. occupied at the altitude higher than 600m. Dicentra spectabilis population and Anemone population were remardable, and Adenophora grandiflora and Astilbe chinensis var. davidii with white flowers were found. 2. The vascular plants in Mt. Myoungji were recorded as 677 taxa such as 19 families, 358 genera 576 species 90 varieties 11 forma. Among them. 19 families 31 genera 32 taxa were endemic plants and 27 taxa were naturalized plants. 3. 26 taxa of rare and endangered plants protected by Forestry Administration were found in Mt. Myonfji. Among them, Asarum maculatum. Hanabusaya asiatica, Lilum cernum. Jeffersonia dubia, and Cypripedium japonica populations could be regarded as very important in a biogeraphical aspect. So it is necessary to monitor this area in a long term and to establish the conservation strategies.