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Compared to Bone Mineral Density between Dominant Side and Recessive Side in Normal Elderly and Stroke Patients (정상노인과 뇌졸중 환자의 우세측과 비우세측의 골밀도 비교)

  • Min, Dong-Ki
    • PNF and Movement
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    • v.11 no.2
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    • pp.127-134
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    • 2013
  • Purpose : The purpose of this study of normal elderly and stroke patients by comparing the dominant side and recessive side was to evaluate the differents between each Methods : Thirty-two elderly participated in this study. They were classified two groups: stroke patients group and the normal elderly group. Outcome measures were: general characteristics and BMD. General characteristics included age, height, weight and body mass index. BMD was represented in the osteoporosis index, T-score and Z-score. The measurements of bone mineral density were evaluated on the calcaneus region of the dominant and recessive side, using OsteoPro. The data analyzed using SPSS 17.0 software and the Paired-sample T-test and the Independent-sample T-test Results : OI, T-score, Z-score showed no significant differences between dominant side and recessive side in normal elderly group. But stroke patients group showed OI, T-score, Z-score significant differences between paretic side and nonparetic side. Change score subtracted recessive side from dominant side was significant differences between stroke patients group and normal elderly group. Conclusion : There is positive relationship between physical activity and BMD in stroke patients. Therefore, improved physical activity can have a beneficial effect by reducing osteoporosis in stroke patients, considering a positive relationship between physical activity and BMD.

High thermoelectric performance and low thermal conductivity in K-doped SnSe polycrystalline compounds

  • Lin, Chan-Chieh;Ginting, Dianta;Kim, Gareoung;Ahn, Kyunghan;Rhyee, Jong-Soo
    • Current Applied Physics
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    • v.18 no.12
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    • pp.1534-1539
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    • 2018
  • SnSe single crystal showed a high thermoelectric zT of 2.6 at 923 K mainly due to an extremely low thermal conductivity $0.23W\;m^{-1}\;K^{-1}$. It has anisotropic crystal structure resulting in deterioration of thermoelectric performance in polycrystalline SnSe, providing a low zT of 0.6 and 0.8 for Ag and Na-doped SnSe, respectively. Here, we presented the thermoelectric properties on the K-doped $K_xSn_{1-x}Se$ (x = 0, 0.1, 0.3, 0.5, 1.5, and 2.0%) polycrystals, synthesized by a high-temperature melting and hot-press sintering with annealing process. The K-doping in SnSe efficiently enhances the hole carrier concentration without significant degradation of carrier mobility. We find that there exist widespread Se-rich precipitates, inducing strong phonon scattering and thus resulting in a very low thermal conductivity. Due to low thermal conductivity and moderate power factor, the $K_{0.001}Sn_{0.999}Se$ sample shows an exceptionally high zT of 1.11 at 823 K which is significantly enhanced value in polycrystalline compounds.

Development of a mobile-based self-management health alarm program for obese children in South Korea and a test of its feasibility for metabolic outcomes: A study based on the information-motivation-behavioral skills model

  • Choi, Jihea;Park, Yon Chul;Choi, Sarah
    • Child Health Nursing Research
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    • v.27 no.1
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    • pp.13-23
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    • 2021
  • Purpose: This study aimed to develop a mobile-based self-management health alarm (MSHA) program for modifying obese children's lifestyle based on the information-motivation-behavioral skills (IMB) model and to test its feasibility. Methods: A methodological study for the development of the MSHA program and pilot study with a one-group pretest-posttest design for feasibility testing was conducted. The MSHA program was designed to provide obesity-related information (I), monitor daily diet and exercise, provide motivational text messages (M), and enhance healthy diet and exercise skills (B) via a mobile-based web platform. In the feasibility test, six obese children participated in the 4-week program, and the number of days per week that they achieved their goals and differences in metabolic components were assessed. Data were analyzed using descriptive statistics and the Wilcoxon signed-rank test. Results: Participants successfully achieved their diet and exercise goals≥5 days per week. Body mass index (z=-1.99, p=.046), waist circumference (z=-2.20, p=.028), and triglyceride levels (z=-2.21, p=.027) significantly decreased. Conclusion: The MSHA program showed positive effects on health behaviors and metabolic syndrome risk. The program may be effective in improving metabolic syndrome in obese children by promoting self-health management behaviors.

MODIFIED CYCLOTOMIC POLYNOMIALS

  • Ae-Kyoung, Cha;Miyeon, Kwon;Ki-Suk, Lee;Seong-Mo, Yang
    • Bulletin of the Korean Mathematical Society
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    • v.59 no.6
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    • pp.1511-1522
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    • 2022
  • Let H be a subgroup of $\mathbb{Z}^*_n$ (the multiplicative group of integers modulo n) and h1, h2, …, hl distinct representatives of the cosets of H in $\mathbb{Z}^*_n$. We now define a polynomial Jn,H(x) to be $$J_{n,H}(x)=\prod^l_{j=1} \left( x-\sum_{h{\in}H} {\zeta}^{h_jh}_n\right)$$, where ${\zeta}_n=e^{\frac{2{\pi}i}{n}}$ is the nth primitive root of unity. Polynomials of such form generalize the nth cyclotomic polynomial $\Phi_n(x)={\prod}_{k{\in}\mathbb{Z}^*_n}(x-{\zeta}^k_n)$ as Jn,{1}(x) = Φn(x). While the nth cyclotomic polynomial Φn(x) is irreducible over ℚ, Jn,H(x) is not necessarily irreducible. In this paper, we determine the subgroups H for which Jn,H(x) is irreducible over ℚ.

Preference for Green Packaging in Consumer Product Choices: Empirical Evidence from Gen Z Consumers in Vietnam

  • Lan, NGUYEN;Trang Minh, NGUYEN;Quyen, TRINH;Nhu Anh, DAO
    • The Journal of Asian Finance, Economics and Business
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    • v.10 no.2
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    • pp.281-300
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    • 2023
  • Recently, the call for better accountability and social responsibility from corporations has been regularly voiced, both in the academic literature and in public discussions. This poses a challenge to the existing literature in understanding consumption behaviors to direct them toward sustainable development. This study investigates the purchase intention of Gen Z consumers in Vietnam with green packaging products. Data were collected from 914 respondents by online questionnaire and then analyzed using OLS. The results suggest the significant influence of customers' income and packaging in driving customers' intention to use environmentally-friendly products. Specifically, consumers in a higher income class participate more actively in green purchases. However, problems associated with inadequate packaging are also illustrated, resulting in the poor perception of green messages and poor practice of ecological actions. Besides, subjective norms and green trust are found to be adversely related to green consumer intention. In addition, gender disparity in green behavior is reported, where female consumers show a higher tendency to ecological consumption than their male counterparts. Other demographic factors are also included in the model as control variables, which are age, education, price, environmental literacy, environmental concern, and psychological awareness, but they do not have a significant impact on green purchase intention.

A study on the occurrence and transfer status of emergency patients at Incheon International Airport (인천국제공항의 응급환자 발생 및 이송 현황에 관한 연구)

  • Ji-in Jo;Kyoung-youl Lee
    • The Korean Journal of Emergency Medical Services
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    • v.27 no.2
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    • pp.51-63
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    • 2023
  • Purpose: The study aimed to analyze the occurrence and transfer status of emergency patients at Incheon International Airport in Korea. Methods: This study design included 810 patients for eight years, from July 1, 2014 to June 31, 2022. The collected data were analyzed with SPSS statistics version 25.0. Results: For the demographics, 531 (65.6%) were males, 151 (19.5%) were in the highest age group (in their 50s), and 289 (35.9%) were foreigners. The most common place of occurrence was in protected areas in the passenger terminal, with 341 (42.1%) of cases occurring here. The time of arrival at the site (z=-3.444, p=.001), stay duration at the site (z=-8.145, p=. 001), and transfer time (z=-3.623, p=.000) were all significantly longer. Conclusion: It is necessary to consider a rapid emergency transportation plan, such as developing a system that simplifies immigration procedures when emergency patients move from protected areas to general areas. Moreover, in order to quickly respond to foreign emergency patients, detailed characteristics will need to be identified. Lastly, considering the long transfer time, an instructing doctor should accompany an ambulance and actively perform advanced resuscitation.

The Relationship between Tree-Ring Growth in Pinus densiflora S. et Z. and the Corresponding Climatic Factors in Korea

  • LEE, Kwang Hee;JO, Sang Yoon;KIM, Soo Chul
    • Journal of the Korean Wood Science and Technology
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    • v.50 no.2
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    • pp.81-92
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    • 2022
  • To analyze the relationship between climatic factors (mean monthly temperature and total precipitation) and tree-ring growths of Pinus densiflora S. et Z. from National Parks (according to region) of the Korea, 20 trees were sampled from 13 National Parks. Only trees that were successfully cross-dated were used for dendrochronological analysis, and at least 11 trees were included. The tree-ring chronology of Mt. Bukhan (covering the shortest period of 1917 - 2016 [100 years]) was assessed, as well as that of Mt. Seorak (covering the longest period of 1687 - 2017 [331 years]). After cross-dating, each ring width series was double-standardized by first fitting a logarithmic curve and then a 50-year cubic spline. The relationships between climate and tree-ring growth were calculated with response function analysis. The results show a significant positive correlation between a given year's February-March temperature, May precipitation levels, and tree-ring growth. It indicates that a higher temperature in early spring and precipitation before cambium activity are important for radial growths of Pinus densiflora in the Korea.

The faintest quasar luminosity function at z ~ 5 from Deep Learning and Bayesian Inference

  • Shin, Suhyun;Im, Myungshin
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.1
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    • pp.31.2-31.2
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    • 2021
  • To estimate the contribution of quasars on keeping the IGM ionized, building a quasar luminosity function (LF) is necessary. Quasar LFs derived from multiple quasar surveys, however, are incompatible, especially for the faint regime, emphasizing the need for deep images. In this study, we construct quasar LF reaching M1450~-21.5 AB magnitude at z ~ 5, which is 1.5 mag deeper than previously reported LFs, using deep images from the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). We trained an artificial neural network (ANN) by inserting the colors as inputs to classify the quasars at z ~ 5 from the late-type stars and low-redshift galaxies. The accuracy of ANN is > 99 %. We also adopted the Bayesian information criterion to elaborate on the quasar-like objects. As a result, we recovered 5/5 confirmed quasars and remarkably minimized the contamination rate of high-redshift galaxies by up to six times compared to the selection using color selection alone. The constructed quasar parametric LF shows a flatter faint-end slope α=-127+0.16-0.15 similar to the recent LFs. The number of faint quasars (M1450 < -23.5) is too few to be the main contributor to IGM ionizing photons.

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Small-scale effects on wave propagation in curved nanobeams subjected to thermal loadings based on NSGT

  • Ibrahim Ghoytasi;Reza Naghdabadi
    • Advances in nano research
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    • v.16 no.2
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    • pp.187-200
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    • 2024
  • This study focuses on wave propagation analysis in the curved nanobeam exposed to different thermal loadings based on the Nonlocal Strain Gradient Theory (NSGT). Mechanical properties of the constitutive materials are assumed to be temperature-dependent and functionally graded. For modeling, the governing equations are derived using Hamilton's principle. Using the proposed model, the effects of small-scale, geometrical, and thermo-mechanical parameters on the dynamic behavior of the curved nanobeam are studied. A small-scale parameter, Z, is taken into account that collectively represents the strain gradient and the nonlocal parameters. When Z<1 or Z>1, the phase velocity decreases/increases, and the stiffness-softening/hardening phenomenon occurs in the curved nanobeam. Accordingly, the phase velocity depends more on the strain gradient parameter rather than the nonlocal parameter. As the arc angle increases, more variations in the phase velocity emerge in small wavenumbers. Furthermore, an increase of ∆T causes a decrease in the phase velocity, mostly in the case of uniform temperature rise rather than heat conduction. For verification, the results are compared with those available for the straight nanobeam in the previous studies. It is believed that the findings will be helpful for different applications of curved nanostructures used in nano-devices.

Systematic Review of Effects of Nasal Continuous Positive Airway Pressure on Apnea of Preterm Infants (미숙아 무호흡을 위한 비강 지속적 양압환기법 효과에 대한 체계적 고찰)

  • Kim, Eun-Joo
    • Child Health Nursing Research
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    • v.20 no.3
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    • pp.225-235
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    • 2014
  • Purpose: The purpose of this study was to analysis the effects of nasal Continuous Postive Airway Pressure (nCPAP) for preterm infants using systematic review and meta-analysis. Methods: Thirteen peer-reviewed journals including preterm infants and apnea and nCPAP published between 1973 and 2013 were included. Effect size and statistics of homogeneity were done using STATA 10.0. Results: The design for 9 studies was Randomized Control Trial. In most of studies the pressure of nCPAP was set to 4-6 cm$H_2O$. The effect size of 5 studies for the effect on apnea rate using nCPAP compared to nasal Intermittent Positive Pressure Ventilator (nIPPV) showed that the Standardized Mean Difference (SMD) was -0.11 and was not significantly different (Z=0.41, p=.680). But the difference in nCPAP for nasal Synchronizes Intermittent Positive Pressure Ventilator (nSIPPV) (subgroup) was significant (SMD=-.44). The effect size of 7 studies on effect for ventilator weaning of using nCPAP compared to nIPPV showed the Risk Ratio (RR) as 1.60 and was not significantly different (Z=1.12, p=.268). But the difference between nCPAP and nSIPPV (subgroup) was significant (RR=3.94). Conclusion: The results indicate a need for an advanced care system and suggest continuous studies of apnea in preterm infants.