Authors:Yong-Jae Kim, Chang-Kyu Kim, Cheol-Su Kim, Ju-Yong Yun, and Byung-Hwan Rho
A time-saving and accurate technique for determining226Ra in groundwater and soil was examined, using high-resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS). The
technique was applied to the determination of226Ra in groundwater and soil samples and compared with the conventional liquid scintillation counting method. This technique
was capable of completing226Ra counting within 3 minutes, without the in-growth period to allow radon and its progeny to achieve secular equilibrium with
the parent226Ra. The detection limits of HR-ICP-MS for226Ra in groundwater and soil were 0.19 mBq·1−1 and 0.75 Bq·kg−1, respectively, which were about 10 times lower than that of the liquid scintillation counter. The results obtained from HR-ICP-MS
in groundwater and soil were in accordance with those of LSC within a relative error of about 13%.
Authors:Wuon-Shik Kim, Hyeon-Soo Kim, Ki-Hwan Kim, Yong-Uhn Kim, and Ki-Hyon Kim
Neutrons from a source are moderated by means of hydrogenous materials such as polyethylene (PE) or water to reduce the energy of fast neutrons and to increase the fluence rate of moderated neutrons. The rise-time and -ray pulse height spectrum from a PE moderated241Am-Be neutron-gamma (n-) mixed source were measured by using6Li-BC501 scintillation detector and pulse shape discriminator (PSD) system. The difference in rise-time between and neutron signals tumed out to be 18.5 ns for the6Li-BC501 (n-) spectrometer system. The figure of merit (FOM) for this separation was estimated to be 1.52, and this was compared with the published results. From this comparison, the6Li-BC501 system has much superior characteristics in (n-) separation to other detector systems. Two Compton edges at around 1.87 and 3.99 MeV which are produced by H(n,)D reaction and by the first excited state of12C* from Be(, n)12C* reaction were also investigated.
The notion of knowledge-based economy premises that technological knowledge be created, accumulated and disseminated through
the interactive learning among principal actors in the national system. This paper analyzes, from a dynamic perspective, the
structure of inter-industrial technological knowledge. Both human-driven disembodied channel and capital-driven embodied channel
are investigated based on network analysis. The set of empirical data covers the Korean manufacturing sector during the 1980s.
Overall, density of network tends to be increasing over time, implying that knowledge network becomes expanded and intensified.
A number of distinctive features are identified between knowledge types and industrial categories. The findings in turn render
important policy implications that should be addressed when developing technology policy. Clearly, the policy framework needs
to be industry-specific and country-specific in accordance with the development stage and industrial structure of reference
Prion protein is encoded by the prion protein gene (PRNP). Polymorphisms of several members of the prion gene family have shown association with prion diseases in several species. Recent studies on a novel member of the prion gene family in rams have shown that prion-related protein gene (PRNT) has a linkage with codon 26 of prion-like protein (PRND). In a previous study, codon 26 polymorphism of PRND has shown connection with PRNP haplotype which is strongly associated with scrapie vulnerability. In addition, the genotype of a single nucleotide polymorphism (SNP) at codon 26 of PRND is related to fertilisation capacity. These findings necessitate studies on the SNP of PRNT gene which is connected with PRND. In goat, several polymorphism studies have been performed for PRNP, PRND, and shadow of prion protein gene (SPRN). However, polymorphism on PRNT has not been reported. Hence, the objective of this study was to determine the genotype and allelic distribution of SNPs of PRNT in 238 Korean native goats and compare PRNT DNA sequences between Korean native goats and several ruminant species. A total of five SNPs, including PRNT c.-114G > T, PRNT c.-58A > G in the upstream of PRNT gene, PRNT c.71C > T (p.Ala24Val) and PRNT c.102G > A in the open reading frame (ORF) and c.321C > T in the downstream of PRNT gene, were found in this study. All five SNPs of caprine PRNT gene in Korean native goat are in complete linkage disequilibrium (LD) with a D’ value of 1.0. Interestingly, comparative sequence analysis of the PRNT gene revealed five mismatches between DNA sequences of Korean native goats and those of goats deposited in the GenBank. Korean native black goats also showed 5 mismatches in PRNT ORF with cattle. To the best of our knowledge, this is the first genetic research of the PRNT gene in goat.
Bovine prion diseases are composed of two types of bovine spongiform encephalopathy (BSE), classical BSE and atypical BSE. Recent studies have identified one case of atypical BSE with an E211K mutation. E211K is homologous to the human E200K mutation, which is related to familial Creutzfeldt-Jakob disease (CJD), one of the familial forms of human prion diseases. To date, familial forms of prion diseases have not been reported in non-human animals. Because the familial forms of human prion diseases account for more than 10% of all human prion disease cases, the detection of the E211K mutation in healthy cattle is very important for verifying the role of this mutation as a familial form of BSE. To detect putative mutations related to familial BSE, specifically E211K in Korean native cattle (Hanwoo) and Korean dairy cattle (Holstein), we performed direct sequencing targeting codon 211 and the adjacent regions of the bovine prion protein (PRNP) gene in 384 Hanwoo and 152 Holstein cattle. We did not find the E211K mutation in any of the Korean cattle. Although we did not find the E211K mutation in Korean native cattle, E211K is a postulated mutation; therefore, further screening in other countries and larger samples is highly desirable.
This study performs a webometric analysis to explore the communication characteristics of scientific knowledge in a national
scholarly Web space comprising top ranking universities and government supported research institutions in South Korea. We
found significant differences in scholarly communication activity as well as linking behavior among different subspaces in
addition to institutional differences. We also found the usefulness of the ADM approach in analyzing the metric data containing
extreme outliers and discovered the directory model as the most appropriate. Page counts were found significantly correlated
with inlinks as well as with outlinks at the directory level in the whole scholarly Web space.
Authors:Sung-Eun Kim, Jin-Woo Kim, and Yong-Seok Jee
Background and Aims
Excessive usage of smartphones may induce social problems, such as depression and impairment of social and emotional functioning. Moreover, its usage can impede physical activity, but the relationship between smartphone addiction and physical activity is obscure. Therefore, we examined the relationship and the impact of excessive smartphone use on physical activity.
This study collected data through the structured questionnaire consisting of general characteristics, the number and hours of smartphone usage, and the Smartphone Addiction Proneness Scale (SAPS) from 110 Chinese international students in Korea. The body composition and physical activity, such as the total daily number of steps and consumed calories, were measured.
In this study, high-risk smartphone users showed less physical activity, such as the total number of steps taken and the average consumed calories per day. Moreover, their body composition, such as muscle mass and fat mass, was significantly different. Among these factors, the hours of smartphone use revealed the proportional relationship with smartphone addiction (β = 0.209, p = 0.026), while the average number of walking steps per day showed a significant reverse proportional tendency in participants with smartphone addiction (β = –0.883, p < 0.001).
Participants with smartphone addiction were less likely to walk for each day. Namely, smartphone addiction may negatively influence physical health by reducing the amount of physical activity, such as walking, resulting in an increase of fat mass and a decrease of muscle mass associated with adverse health consequences.
Authors:Wuon-Shik Kim, Hyon-Soo Kim, Jong-Youl Kim, Ki-Hwan Kim, Yong-Uhn Kim, and Kwang-Pill Lee
The 1.369 MeV -rays emitted from24Na
–+ after23Na(n,)24Na reaction were counted by high purity germanium (HPGe) detector and the half-life of24Na was derived. This process was simulated by Monte Carlo Neutron and Photon Transport Code (MCNP-4A).252Cf neutron source was moderated by a polyethylene (PE) cylinder to increase the cross section of neutron absorption reaction and to decrease the biological hazard. NaCl powder of 20 cm3 and 40 cm3 volume in cylindrical polypropylene capsules were irradiated by the neutrons passed through the moderator. MCNP-4A was used to determine the optimum size of PE moderator, to assume the realistic geometry of the HPGe detector, and to assume the absolute efficiencies of the detector. The count rates for 1.369 MeV -rays in the HPGe detector were calculated by MCNP-4A for 20 cm3 and 40 cm3 NaCl. The accumulated counts calculated tumed out to be higher than those actually measured by 31% with a relative error of 3%. The half-life of24Na measured within 4% and 1% for 20 cm3 and 40cm3 NaCl agrees with that of the reference. So, we can say that the result of MCNP-4A has about 30% of accuracy and 3% of precision in simulating the neutron activation analysis.
Authors:Hyun-Je Cho, Yong-Sam Chung, and Young-Jin Kim
A prompt gamma activation analysis facility has been constructed on the ST1 horizontal beam port at the HANARO research reactor, KAERI in 2003. The detector system consists of a high-purity Ge detector surrounded by BGO/NaI(Tl) scintillators as an annulus type to reject the Compton scattered photons. Detection sensitivity for boron was obtained from the prompt gamma-ray spectra of boric acid, B(OH)3, containing 0.1-65 μg boron. The net peak for the calculation of the boron concentration was obtained by eliminating the sodium 472 keV peak, involved in the boron 478 keV peak. The biological samples used are NIST SRMs such as Peach Leaves, Apple Leaves, Tomato Leaves, Spinach Leaves, Total Diet, Typical Diet, Oyster Tissue and Corn Bran, etc. The measured values for high boron concentration showed up to a 3% of the relative, but in a low concentration below 5 ppm, present values were higher than the certified ones.
Interferon-induced transmembrane protein 3 (IFITM3) plays a pivotal role in antiviral capacity in several species. However, to date, investigations of the IFITM3 protein in cattle have been rare. According to recent studies, interspecific differences in the IFITM3 protein result in several unique features of the IFITM3 protein relative to primates and birds. Thus, in the present study, we investigated the bovine IFITM3 protein based on nucleotide and amino acid sequences to find its distinct features. We found that the bovine IFITM3 gene showed a significantly different length and homology relative to other species, including primates, rodents and birds. Phylogenetic analyses indicated that the bovine IFITM3 gene and IFITM3 protein showed closer evolutionary distance with primates than with rodents. However, cattle showed an independent clade among primates, rodents and birds. Multiple sequence alignment of the IFITM3 protein indicated that the bovine IFITM3 protein contains 36 bovine-specific amino acids. Notably, the bovine IFITM3 protein was predicted to prefer inside-to-outside topology of intramembrane domain 1 (IMD1) and inside-to-outside topology of transmembrane domain 2 by TMpred and three membrane embedding domains according to the SOSUI system.