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Butterfly Diversity, Distribution, and Abundance in the University of Port Harcourt River State, Nigeria

  • Efenakpo, Ogaga Dean;Zakka, Usman;Omanoye, Dokubo ThankGod
    • Journal of Forest and Environmental Science
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    • v.37 no.3
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    • pp.243-250
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    • 2021
  • Information on butterflies in the Niger Delta Region is relatively scanty because monitoring of their activities and distribution has not been fully documented and these are paramount to establish their conservation protocols. The study therefore aimed at evaluating the species richness distribution pattern, and relative abundance of butterflies in the University of Port Harcourt. The University Park was purposively selected for this study. The park was stratified into three different habitat types (secondary forest, farmland, and residential/garden). A sampling of each stratum was done three times; twice in the morning between 8:00 am and 12:00 pm as well as once in the evening between 4:00 pm and 6:00 pm along a 100 m line transects for 16 months (May 2017-August 2018). Data collected were analyzed for species diversity indices, evenness, and similarity index. A total of 1,932 individual butterflies belonging to 28 species, 18 genera, and five 5 families were identified in the study area. Species diversity and evenness were higher on farmland (1-D=0.909; H'=2.615; E=0.833), and least in the residential area/gardens (1-D=0.744; H'=1.975; E=0.659). The family Nymphalidae (39.0%) had the highest number of species occurrence while Hesperidae (0.4%) had the lowest composition. Anthene larydas (24.12%) had the highest relative abundance in the entire study area, followed by Acraea serena (17.49%). The study, therefore, recommends continuous monitoring of butterfly species diversity and composition also in other regions.

Correlation between Methane (CH4) Emissions and Root Aerenchyma of Rice Varieties

  • Kim, Woo-Jae;Bui, Liem T.;Chun, Jae-Buhm;McClung, Anna M.;Barnaby, Jinyoung Y.
    • Plant Breeding and Biotechnology
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    • v.6 no.4
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    • pp.381-390
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    • 2018
  • Percentage of aerenchyma area has been closely linked with amounts of methane emitted by rice. A diversity panel of 39 global rice varieties were examined to determine genetic variation for root transverse section (RTS), aerenchyma area, and % aerenchyma. RTS and aerenchyma area showed a strong positive correlation while there existed no significant correlation between RTS area and % aerenchyma. Five varieties previously shown to differ in methane emissions under field conditions were found to encompass the variation found in the diversity panel for RTS and aerenchyma area. These five varieties were evaluated in a greenhouse study to determine the relationship of RTS, aerenchyma area, and % aerenchyma with methane emissions. Methane emissions at physiological maturity were the highest for 'Rondo', followed by 'Jupiter', while 'Sabine', 'Francis' and 'CLXL745' emitted the least. The same varietal rank, 'Rondo' being the largest and 'CLXL745' the smallest, was observed with RTS and aerenchyma areas. RTS and aerenchyma area were significantly correlated with methane emissions, r = 0.61 and r = 0.57, respectively (P < 0.001); however, there was no relationship with % aerenchyma. Our results demonstrated that varieties with a larger root area also developed a larger aerenchyma area, which serves as a gas conduit, and as a result, methane emissions were increased. This study suggests that root transverse section area could be used as a means of selecting germplasm with reduced $CH_4$ emissions.

Mechanistic investigations on emission characteristics from g-C3N4, gC3N4@Pt and g-C3N4@Ag nanostructures using X-ray absorption spectroscopy

  • Sharma, Aditya;Varshney, Mayora;Chae, Keun Hwa;Won, Sung Ok
    • Current Applied Physics
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    • v.18 no.11
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    • pp.1458-1464
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    • 2018
  • An improved method for the preparation of g-$C_3N_4$ is described. Currently, heating (> $400^{\circ}C$) of urea is the common method used for preparing the g-$C_3N_4$. We have found that sonication of melamine in $HNO_3$ solution, followed by washing with anhydrous ethanol, not only reduce the crystallite size of g-$C_3N_4$ but also facilitate intriguing electronic structure and photoluminescence (PL) properties. Moreover, loading of metal (Pt and Ag) nanoparticles, by applying the borohydride reduction method, has resulted in multicolor-emission from g-$C_3N_4$. With the help of PL spectra and local electronic structure study, at C K-edge, N K-edge, Pt L-edge and Ag K-edge by X-ray absorption spectroscopy (XAS), a precise mechanism of tunable luminescence is established. The PL mechanism ascribes the amendments in the transitions, via defect and/or metal states assimilation, between the ${\pi}^*$ states of tris-triazine ring of g-$C_3N_4$ and lone pair states of nitride. It is evidenced that interaction between the C/N 2p and metal 4d/5d orbitals of Ag/Pt has manifested a net detraction in the ${\delta}^*{\rightarrow}LP$ transitions and enhancement in the ${\pi}^*{\rightarrow}LP$ and ${\pi}^*{\rightarrow}{\pi}$ transitions, leading to broad PL spectra from g-$C_3N_4$ organic semiconductor compound.

Prediction of Covid-19 confirmed number of cases using ARIMA model (ARIMA모형을 이용한 코로나19 확진자수 예측)

  • Kim, Jae-Ho;Kim, Jang-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.12
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    • pp.1756-1761
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    • 2021
  • Although the COVID-19 outbreak that occurred in Wuhan, Hubei around December 2019, seemed to be gradually decreasing, it was gradually increasing as of November 2020 and June 2021, and estimated confirmed cases were 192 million worldwide and approximately 184 thousand in South Korea. The Central Disaster and Safety Countermeasures Headquarters have been taking strong countermeasures by implementing level 4 social distancing. However, as the highly infectious COVID-19 variants, such as Delta mutation, have been on the rise, the number of daily confirmed cases in Korea has increased to 1,800. Therefore, the number of cumulative confirmed COVID-19 cases is predicted using ARIMA algorithms to emphasize the severity of COVID-19. In the process, differences are used to remove trends and seasonality, and p, d, and q values are determined and forecasted in ARIMA using MA, AR, autocorrelation functions, and partial autocorrelation functions. Finally, forecast and actual values are compared to evaluate how well it was forecasted.

STRATEGIC RESEARCH AT ORNL EOR THE DEVELOPMENT OF ADVANCED COATED CONDUCTORS: PART - II

  • Paranthama, M. Parans;Aytug, T.;Sathyamurthy, S.;Zhai, H.Y.;Christen, H.M.;Martin, P.M.;Goyal, A.;Christen, D.K.;Kroeger, D.M.
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2002.02a
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    • pp.340-340
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    • 2002
  • In an effort to develop alternative single buffer layer technology for YBa$_2$Cu$_3$O$_{7-{\delta}}$ (YBCO) coated conductors, we have investigated both LaMnO$_3$, (LMO) and La$_2$Zr$_2$O$_{7}$ (LZO) as potential buffer layers. High-quality LMO films were grown directly on textured Ni and Ni-W (3%) substrates using rf magnetron sputtering. Highly textured LZO buffers were grown on textured Ni substrates using sol-gel alkoxide processing route. YBCO films were then grown on both LMO and LZO buffers using pulsed laser deposition. Detailed X-ray studies have shown that YBCO films were grown on both LMO and LZO layers with a single epitaxial orientation. A high J$_{c}$ of over 1 MA/cm$^2$ at 77 K and self-field was obtained on YBCO films grown on both LMO-buffered Ni or Ni-W substrates, and also on LZO-buffered Ni substrates. We have identified LaMnO$_3$ as a good diffusion barrier layer for Ni and it also provides a good template for growing high current density YBCO films. Similarly we have also demonstrated the growth of high J$_{c}$ YBCO films on all solution buffers. We will discuss in detail about our buffer deposition processes. processes.s.s.s.s.

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Distribution of Freshwater Organisms in the Pyeonggang Stream and Application Effects of Hydrothermal Energy on Variations in Water Temperature by Return Flow in a Stream Ecosystem

  • Dohun Lim;Yoonjin Lee
    • Economic and Environmental Geology
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    • v.56 no.2
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    • pp.185-199
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    • 2023
  • This study aimed to predict the effects of water ecology on the supply of hydrothermal energy to model a housing complex in Eco Delta Smart Village in Busan. Based on the results, engineering measures were recommended to minimize problems due to possible temperature variations on the supply of hydrothermal energy from the river. The current distribution of fish, benthic macroinvertebrates, and phytoplankton in the Pyeonggang Stream was monitored to determine their effects on water ecology. In the research area, five species and three families of fish were observed. The dominant species was Lepomis macrochirus, and the subdominant species was Carassius auratus. Twenty-five species and 21 families of benthic macroinvertebrates were found. The distribution of aquatic insects was poor in this area. The dominant species were Chironomidae sp., Lymnaea auricularia, Appasus japonicus, and Caridina denticulata denticulata in February, May, July, and October. Dominant phytoplankton were Aulacoseira ambigua and Nitzschia palea in February and May. Microcystis sp. was dominant in July and October. The health of the ecology the Pyeonggang Stream was assessed as D (bad) according to the benthic macroinvertebrate index (BMI). Shifts in the location of the discharge point 150 m downstream from intake points and discharge through embedded rock layer after adding equal amounts of stream water as was taken at the beginning were suggested to minimize water temperature variations due to the application of hydrothermal energy. When the scenario (i.e., quantity of water intake and dilution water, 1,600 m3/d and water temp. difference ±5 ℃) was realized, variations in water temperature were assessed at -0.19 ℃ and 0.59 ℃ during cooling and heating, respectively, at a point 10 m downstream. Water temperatures recorded at -0.20 ℃ and 0.68 ℃ during cooling and heating, respectively, at a point 10 m upstream. All stream water temperatures after the application of hydrothermal energy recovered within 24 hours. Future work on the long-term monitoring of ecosystems is suggested, particularly to analyze the influence of the water environment on hydrothermal energy supply operations.

The effectiveness of Ceravida recovery technology on sleeping factors in bedding : Quantitative evaluation (Ceravida recover 기술이 적용된 침구류의 수면요인 효과분석 : 정량적평가)

  • Kim, Jong-Geun;Kim, Ji-Young;Lee, Young-Ik
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.6
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    • pp.273-280
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    • 2023
  • The purpose of this study is to investigate the effect of functional bedding of ceravida recovery materials on muscle fatigue, brain waves, and heat in the cervical spine before and after sleep. The subjects of the study were 12 women in their 50s or older in D Metropolitan City who complained of insomnia due to sleep disorders and cervical pain. The results of this study first showed that functional bedding lowered muscle tension. Second, the skin temperature of cervical spine increased statistically significantly for both functional and general bedding. Third, there was a statistically significant difference in EEG(alpha, beta, theta, delta) of functional bedding. Through these results, it is considered that functional bedding of ceravida recovery material has sufficient effect on sleep recovery technology.

A Theoretical Model for the Analysis of Residual Motion Artifacts in 4D CT Scans (이론적 모델을 이용한 4DCT에서의 Motion Artifact 분석)

  • Kim, Tae-Ho;Yoon, Jai-Woong;Kang, Seong-Hee;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.23 no.3
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    • pp.145-153
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    • 2012
  • In this study, we quantify the residual motion artifact in 4D-CT scan using the dynamic lung phantom which could simulate respiratory target motion and suggest a simple one-dimension theoretical model to explain and characterize the source of motion artifacts in 4DCT scanning. We set-up regular 1D sine motion and adjusted three level of amplitude (10, 20, 30 mm) with fixed period (4s). The 4DCT scans are acquired in helical mode and phase information provided by the belt type respiratory monitoring system. The images were sorted into ten phase bins ranging from 0% to 90%. The reconstructed images were subsequently imported into the Treatment Planning System (CorePLAN, SC&J) for target delineation using a fixed contour window and dimensions of the three targets are measured along the direction of motion. Target dimension of each phase image have same changing trend. The error is minimum at 50% phase in all case (10, 20, 30 mm) and we found that ${\Delta}S$ (target dimension change) of 10, 20 and 30 mm amplitude were 0 (0%), 0.1 (5%), 0.1 (5%) cm respectively compare to the static image of target diameter (2 cm). while the error is maximum at 30% and 80% phase ${\Delta}S$ of 10, 20 and 30 mm amplitude were 0.2 (10%), 0.7 (35%), 0.9 (45%) cm respectively. Based on these result, we try to analysis the residual motion artifact in 4D-CT scan using a simple one-dimension theoretical model and also we developed a simulation program. Our results explain the effect of residual motion on each phase target displacement and also shown that residual motion artifact was affected that the target velocity at each phase. In this study, we focus on provides a more intuitive understanding about the residual motion artifact and try to explain the relationship motion parameters of the scanner, treatment couch and tumor. In conclusion, our results could help to decide the appropriate reconstruction phase and CT parameters which reduce the residual motion artifact in 4DCT.

$Hg^{2+}$-induced Aquation of trans-[Co(3,2,3-tet)$X_2]^+$ (3,2,3-tet = 4,7-diazadecane-1,10-diamine, $X_2\;=\;Cl_2,\;(NO_2)Cl,\;Br_2,\;(NO_2)Br,\;and\;(NO_3)_2)$ Complexes in Aqueous Solution (수용액에서 $Hg^{2+}$에 의한 trans-[Co(3,2,3-tet)X$_2]^+$ (3,2,3-tet = 4,7-diazadecane-1,10-diamine, $X_2\;=\;Cl_2,\;(NO_2)Cl,\;Br_2,\;(NO_2)Br,\;(NO_3)_2)$ 착물의 아쿠아 반응)

  • Doo Cheon Yoon;Chang Eon Oh;Myung Ki Doh
    • Journal of the Korean Chemical Society
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    • v.37 no.11
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    • pp.951-960
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    • 1993
  • $Hg^{2+}$-induced aquation trans-[Co(3,2,3-tet)$X_2]^+$(3,2,3-tet = 4,7-diazadecane-1,10-diamine, $X_2\;=\;Cl_2,\;(NO_2)Cl,\;Br_2,\;(NO_2)Br,\;(NO_3)_2)$ complexes was investigated in aqueous solution. The products and the reaction mechanism were confirmed by chromatography, UV/Vis. spectrum, and circular dichroism (CD) spectrum. From the results, $Hg^{2+}$-induced aquation of 3,2,3-tet system has been produced cis-${\beta}$ complex via trans complex. The kinetic studies on $Hg^{2+}$-induced aquation of trans-[Co(3,2,3-tet)$Cl_2]^+$ complex and trans-[Co(3,2,3-tet)$(NO_2)Cl]^+$ complex were also carried out to study the reaction mechanism. The results show that trans-[Co(3,2,3-tet)$Cl_2]^+$ complex undergoes the D(dissociative)-mechanism and trans-[Co(3,2,3-tet)$(NO_2)Cl]^+$ complex $I_d$(interchange dissociavite)-mechanism. In order to confirm steric course for the reaction mechanism, $Hg^{2+}$-induced aquation on trans-[Co(R,R-3,2,3-tet)$Cl_2]^+$ complex to which chiral R,R-3,2,3-tet was coordinated instead of the racemic(R,R:S,S) 3,2,3-tet was used has been examined by CD spectrum. From the results, the final complex was confirmed to be ${\Delta}-cis-{\beta}$-[Co(R,R-3,2,3-tet)$(OH_2)_2]^{3+}$ complex indicating the chirality was retained through whole process.

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Influence of Helicobacter pylori Infection on Gastric Motility in Children and Adolescents with Functional Dyspepsia (기능성 소화불량 소아청소년에서 위 운동에 대한 Helicobater pylori 감염의 영향)

  • Ryoo, Eell;Nam, Yoo-Nee;Kweon, Chang-Kyu;Kang, Sung-Kil;Cho, Kang-Ho;Son, Dong-Woo;Tcha, Hann
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.12 no.2
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    • pp.133-139
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    • 2009
  • Purpose: In spite of many reports about Helicobacter pylori infection in children with functional gastrointestinal disorders, there are few reports about the influence of H. pylori infection to functional dyspepsia and gastric motility. Therefore, we studied the influence of H. pylori infection on gastric myoelectrical activity in children with functional dyspepsia. Methods: Between August 2006 and December 2008 upper gastrointestinal endoscopies with biopsies, the rapid urease test and/or $^{13}C$ urea breath test, and electrogastrography (EGG) were performed on 63 patients with histologic chronic gastritis; patients with chronic disorders were excluded. Comparisons about gastric myoelectrical activities were made between H. pylori-positive children (n=25) and H. pylorinegative children (n=38). Results: The percentage of pre- and post-prandial normogastria was relatively lower in H. pylori-positive children than H. pylori-negative children (80% vs. 65%, and 80% vs. 68%, respectively). Compared to H. pylori-negative children, H. pylori-positive children had lower postprandial predominant power (8.18${\pm}$22.36 dB and 32.20${\pm}$24.18 dB, respectively; p<0.01) and a lower power ratio (${\delta}P$; -1.28${\pm}$6.18 vs. +4.62${\pm}$5.93, respectively; p<0.01). Conclusion: It was suggested that the gastric myoelectrical activity in children with chronic gastritis can be influenced by H. pylori infection. Thus, this study indicates that H. pylori infection may be predictable in children with functional dyspepsia through analyzing the EGG parameters, and treatment may be considered in H. pylori-positive children with impaired gastric activity, especially in the lower prevalence area.

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