• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.76.1-76.1
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• 2016

During the last decade, high-resolution spectra of many very metal-poor (VMP) stars have been observed and their surface compositions have been measured. The abundance patterns of the VMP stars strongly constrain the nucleosynthesis of Pop III stars because they born from material enriched by supernovae or wind ejecta of Pop III stars. The observations show overabundances of light elements like C, N, O, Na, Mg and Al and very low $C^{12}/C^{13}$ ratios. These results indicate that mixing between the H-burning and He-burning region occurred in Pop III stars. To explain these observational results, we performed 1D stellar evolution simulations for non-rotating Pop III stars with ZAMS masses ranging from $20M_{\Box}$ to $50M_{\Box}$ and various overshooting parameters. In our grid calculation, convective mixing between helium burning layers and the hydrogen burning shell generally occurred in models with masses less than $40M_{\Box}$ without rotation and these models show an excess of light element abundances. From this result, it is expected that we could explain the observed abundance patterns with convective mixing in non-rotating massive Pop III stars and we do not necessarily have to invoke rotational mixing.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1218-1223
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• 2021

A hydrophobic ionic liquid including an amino moiety ([DiOcAPmim][NTf₂]) was synthesized. Its extraction behaviors towards Pd(II), Ru(III), Rh(III) were investigated in nitric acid aqueous solution as a function of contact time, effect of concentration of nitric acid, effect of temperature, and effect of co-existing metal ions. The extraction kinetics of Pd(II) was fairly fast and extraction equilibrium can be attained within only 5 min under the [HNO₃] = 2.05 M. When [HNO₃]< 1 M, the extraction percentage of Pd(II), Ru(III), Rh(III) were all above 80%. When [HNO₃] reached 2 M, all of the extraction percentage decreased and in an order of Pd(II)>Ru(III)>Rh(III). When [HNO₃]> 2 M, the extraction performance gradually recovered. The effect of temperature can slightly affect the extraction performance of Pd(II). Furthermore, in simulated high-level liquid waste, [DiOcAPmim][NTf₂] showed a better preference towards Pd(II) under the interference of various other co-existing metal ions.

• Journal of the Korean Society of Safety
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• v.38 no.5
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• pp.15-26
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• 2023

The relationship between the knowledge, attitude, and practice of the person in charge of designating a Class III facility was analyzed to improve its practice. As a field of knowledge, system knowledge and technical knowledge were considered, and attitudes were divided into cognitive, affective, and behavioral attitudes. A knowledge, attitude, and practice (KAP) survey was conducted, and the relationship among them was analyzed through correlation and regression analyses. The factors affecting the level of practice in designating the Class III facility were technical knowledge in the field of knowledge and cognitive and behavioral attitudes in the field of attitudes. Cognitive and behavioral attitudes were the two factors that most influenced the practice of designating a Class III facility. It is thought that the higher the level of cognitive and behavioral attitudes, the greater the ability to practice designating the Class III facility. The general characteristics of respondents influencing cognitive and behavioral attitudes were analyzed by safety inspection.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1293-1296
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• 2006

In this study, a solid phase extraction method has been developed for the preconcentration and separation of the elements Cr(III), Fe(III), Co(II) and Pb(II) at trace levels by using a column packed with Amberlite XAD-1180 resin loaded with 4-(2-pyridylazo)-resorcinol (PAR) reagent. After preconcentrating, the metals retained on the column were eluted with 20 mL of 3 mol/L $HNO_3$ and then determined by flame atomic absorption spectrometry (FAAS). The factors affecting the recovery of the elements, such as pH, type and concentration of eluent, volume of sample and elution solution, and matrix components, were also ascertained. The recoveries of Cr(III), Fe(III), Co(II) and Pb(II) were found to be $99\;{\pm}\;4,\;97\;{\pm}\;3,\;95\;{\pm}\;3$ and $98\;{\pm}\;4$%, respectively, under the optimum conditions at 95% confidence level and the relative standard deviations found by analyzing of nine replicates were $\leq4.4$%. The preconcentration factors for Cr(III), Fe(III), Co(II) and Pb(II) were found as 75, 125, 50 and 75 respectively. The detection limits (DL, 3s/b) were 3.0 $\mu g/L$ for Cr(III), 1.25 $\mu g/L$ for Fe(III), 3.3 $\mu g/L$ for Co(II), and 7.2 $\mu g/L$ for Pb(II). The recoveries achieved by adding of metals at known concentrations to samples and the analysis results of Buffalo river sediment (RM 8704) show that the described method has a good accuracy. The proposed method was applied to tap water, stream water, salt and street dust samples.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.1
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• pp.13-26
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• 2010

Objectives : This study was designed to evaluate neuroprotective effects of Neutral Pharmacopuncture for Blood Stasis(NPBS) into SP10 and Tangguisusangami-tang (dangguixusanjiawei-tang)(TGT) in the experimental Traumatic Brain Injury(TBI)rats. Methods : Male rats were divided into 4 groups. Group I was no treatment after TBI. Group II was treatment with NPBS into SP10 after TBI. Group III was treatment with TGT after TBI. Group IV was NPBS into SP10 and TGT after TBI. The author carried out neurological motor behavioral, histological assessment test. Results : 1. In neurological motor behavior tests, motor and cognitive function recovery was significantly increased in the Group II, III, IV. Also Group IV was increased as compared with Group II, III. 2. In BAX expression, according to priority Group IV, III, II, I were decresed in 7 and 14 days later. Especially Group IV was significantly decreased in 14 days later. 3. In BCL-2 expression, Group IV was increased slightly in 7 days later. Most incresed expression was experimented in the Group IV in 14 days later. 4. In TUNEL expression, IV was decreased as compared with each Group I, II, III in 7 days later. Group IV, III were decreased as compared with each Group I, II, III in 14 days later. Conclusions : According to the results, NPBS and TGT can inhibit apoptosis of cells after TBI in rats by contol of BAX and BCL-2, TUNEL expression. And also can help neurological motor behavioral function.

• Journal of the Korean School Mathematics Society
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• v.9 no.4
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• pp.557-573
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• 2006

The purpose of this study is to examine the usefulness of teaching Maple in College Mathematics Education. The subject are 60 students of college of science in H university and C university located in Daejeon. They were divided into two parts; an experimental group (group I, group II, each of 20 students) and a control group (group III of 20 students). The group I and II are provided calculus lecture in class as well as Maple lab, while group III are lectured only in class. In order to know the effectiveness of using Maple, a test is designed in the way that group I is allowed to use both pencil and Maple, while group II and III are restricted to use only pencil. The result of this study is as follows. i) According to the performance of testing exam, there is no significant difference between three groups (p>.05) when they are allowed to use only pencil. ii) The achievement of group I is much higher than that of group II and III (p<.05) when they were provided both pencil and Maple. iii) Lot of students in group I who fail to solve with pencil can succeed in solving problems using Maple.

• The korean journal of orthodontics
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• v.32 no.1 s.90
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• pp.33-42
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• 2002

This study was performed to compare the pattern of dentoalveolar characteristics in different vertical and anteroposterior skeletal types in skeletal Class III malocclusion. The samples selected for this study were consisted of 60 subjects(29 males and 31 females, mean age; 19.7 years) in Class III group, 43 subjects(14males and 29 females, mean age : 20.5 years) in normal group. The findings of this study were as follows : 1. The IMPA of the Class III group was smaller than that of the Class I group(p<0.01). 2. In the Class III groups, SNB and NtoPog had negative correlation with IMPA(p<0.01). The SNB and NtoPog had correlations with SNU1, FHU1 and PalU1(p<0.01) in the male samples, and in the female samples, the SNB and NtoPog had correlations with SNU1(p<0.01). 3. In the Class III male samples, SNMP, FMA, PalMP had negative correlation with IMPA(p<0.01). SNMP, FMA, PalMP had not significant correlation with SNU1, FHU1, PalU1. In the Class III female samples, FMA, PalMP had negative correlation with IMPA(p<0.01). 4. In the high angle group of Class III samples, SNU1, IMPA is smaller than that of low angle group of Class III samples(p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.6
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• pp.887-894
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• 2016

This study was conducted to compare the effects of layout of furniture (a perch, nest, and sandbox) in cages on behavior and welfare of hens. Two hundred and sixteen Hyline Brown laying hens were divided into five groups (treatments) with four replicates per group: small furnished cages (SFC), medium furnished cages type I (MFC-I), medium furnished cages type II (MFC-II), and medium furnished cages type III (MFC-III) and conventional cages (CC). The experiment started at 18 week of age and finished at 52 week of age. Hens' behaviors were filmed during the following periods: 8:00 to 10:00; 13:00 to 14:00; 16:00 to 17:00 on three separate days and two hens from each cage were measured for welfare parameters at 50 wk of age. The results showed that feeding and laying of all hens showed no effect by cage type (p>0.05), and the hens in the furnished cages had significantly lower standing and higher walking than CC hens (p<0.05). The birds in MFC-III had significant higher preening, scratching and feather-pecking behavior than in the other cages (p<0.05). No difference in nesting behavior was found in the hens between the furnished cages (p>0.05). The hens in MFC-I, -II, and -III showed a significant higher socializing behavior than SFC and CC (p<0.05). The lowest perching was for the hens in SFC and the highest perching found for the hens in MFC-III. Overall, the hens in CC showed poorer welfare conditions than the furnished cages, in which the feather condition score, gait score and tonic immobility duration of the hens in CC was significantly higher than SFC, MFC-I, MFC-II, and MFC-III (p<0.05). In conclusion, the furnished cage design affected both behavior and welfare states of hens. Overall, MFC-III cage design was better than SFC, MFC-I, and MFC-II cage designs.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.1
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• pp.58-68
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• 2015

Requirements to control the large decrease in serum calcium (Ca) due to parturition and to increase the feed intake soon after parturition have been well accepted in dairy cows. This study was aimed to investigate the feed intake affected by serum Ca concentration with difructose anhydride (DFA) III supplement in dairy cows soon after parturition. Fourteen transition Holstein cows were divided into DFA and control (CONT) groups within 1 to 5 parity variations in each group. Measurement schedule for an individual cow was from 14 d before parturition to 7 d following parturition. The cows in DFA group were supplied 0.2 kg/head/d of DFA III feed containing 40 g of pure DFA III while the cows in CONT group received no DFA III. Other feeding procedures were the same for all cows in both groups. At parturition (d 0), serum Ca concentration sharply declined in both groups (p<0.05). Time interval for recovery from decreased serum Ca to its normal range (>9.0 mg/dL) tended to be faster in DFA group (12 h) than in the CONT group (48 h), but the differences were not significant. Active ruminal contraction was observed in DFA group at following parturition of d 1 (p<0.05), d 3 (p<0.05), and d 5 (p<0.01). Dry matter (DM) intake did not differ between the groups. However, positive correlations were observed between serum Ca concentration and ruminal contraction (p<0.001), and between ruminal contraction and DM intake (p<0.001) during following parturition. According to multiple regression analysis ($R^2$ = 0.824, p<0.001), the DM intake was positively affected by serum Ca concentration and ruminal contraction. These results suggest that feed intake soon after parturition in dairy cows can be increased by improvement of serum Ca concentration and active ruminal contraction, but DFA III supplementation in this study did not improve the lower serum Ca concentration due to parturition.

• Journal of Life Science
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• v.24 no.2
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• pp.186-190
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• 2014

Carbonic anhydrase isozymes (CAs) are widespread zinc-containing metalloenzyme family. The enzyme catalyzes the reversible interconversion of $CO_2$ and $HCO_3$. This reaction is the main role of CA enzymes in physiological conditions. CA III, one of the CA isozymes, has been identified in many tissues. It is distinguished from the other isozymes by several characteristics, particularly by a lower specific activity and by its resistance to acetazolamide. However, the physiological function of CA III in fish is unknown. In this study, we examined the detection of CAs in the Shaggy sea raven Hemitripterus villosus, using SDS-PAGE, isoelectric focusing (IEF), and western blot analysis. We detected a significant protein band with molecular weight about 30 kDa from the tissues of H. villosus by SDS-PAGE and western blotting. A specific band of CA III with pI 7.0 was detected by IEF and western blotting in gill and muscle. The immunoreaction of anti-CA III expressed in the gill of H. villosus was much stronger than other tissues. One explanation for this result is that the fish gill is the only organ that is exposed to the external environment and that plays an important role in acid-base relevant ion transfer, the transfer of $H^+$ and/or $HCO{_3}^-$, for the maintenance of systemic pH. This is the first report on the identification of a carbonic anhydrase III-like protein from H. villosus.