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Constraints and opportunities to sustain future wheat yield and water productivity in semi-arid environment

  • Ahmad, Mirza Junaid;Choi, Kyung-Sook
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.185-185
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    • 2019
  • Sustaining future wheat production is challenged by anthropogenically forced climate warming and drying led by increased concentration of greenhouse gases all around the globe. Warming stresses, originating from the elevated $CO_2$ concentration, are continuously reported to have negative impacts on wheat growth and yield. Yet, elevated $CO_2$ concentration, despite being disparagingly blamed for promoting warming, is also associated with a phenomenon called $CO_2$ enrichment; in which wheat yield can improve due to the enhanced photosynthesis rates and less water loss through transpiration. The conflicting nature of climate warming and $CO_2$ enrichment and their interplay can have specific implications under different environments. It is established form the field and simulation studies that the two contrasting phenomena would act severely in their own respect under arid and semi-arid environments. Wheat is a dietary staple for masses in Pakistan. The country's wheat production system is under constant stress to produce more from irrigated agricultural lands, primarily lying under arid to semi-arid environments, to meet the rapidly growing domestic needs. This work comprehensively examines the warming impacts over wheat yield and water productivity (WP), with and without the inclusion of $CO_2$ enrichment, under semi-arid environment of Punjab which is the largest agricultural province of Pakistan. Future wheat yields and WPs were simulated by FAO developed AquaCrop model v 5.0. The model was run using the bias-correction climate change projections up to 2080 under two representative concentration pathways (RCP) scenarios: 4.5 and 8.5. Wheat yield and WPs decreased without considering the $CO_2$ enrichment effects owing to the elevated irrigation demands and accelerated evapotranspiration rates. The results suggested that $CO_2$ enrichment could help maintain the current yield and WPs levels during the 2030s (2021-2050); however, it might not withhold the negative climate warming impacts during the 2060s (2051-2080). Furthermore, 10 - 20 day backward shift in sowing dates could also help ease the constraints imposed by climate warming over wheat yields and WPs. Although, $CO_2$ enrichment showed promises to counteract the adverse climate warming impacts but the interactions between climate warming and $CO_2$ concentrations were quite uncertain and required further examination.

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Current Research Trends on Prevalence, Correlates with Cognitive Function, and Intervention on Sarcopenia in Community-dwelling Older Adults: Systematic Review (지역사회 거주 노인의 근감소증 유병률, 인지기능과의 관계 및 중재연구 동향: 체계적 문헌고찰)

  • Ahn, Soojung;Chu, Sang Hui;Jung, Hyejeong
    • 한국노년학
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    • v.36 no.3
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    • pp.727-749
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    • 2016
  • This systematic review was performed to investigate relationship between sarcopenia and cognitive function among community-dwelling older adults. Studies which reported prevalence rates of sarcopenia in community-dwelling older adults, relationships between sarcopenia and cognitive dysfunction, or effective interventions in alleviated symptoms of sarcopenia were selected. Of 43 studies reviewed, prevalence rate of sarcopenia ranged from 2.5-42.4% in 25 studies, and 4 studies revealed a significantly positive correlation between sarcopenia and cognitive dysfunction. Among 12 randomized-control trials (RCTs), exercise intervention was used in 2 studies; nutrition intervention in 6; and 4 studies included both the exercise and nutrition interventions. All interventional studies reported positive effects on muscle mass, muscle strength, or physical function. However, only 6 studies met the high quality criteria of Risk of Bias, and there was no study which evaluated cognitive function as an outcome measure. Therefore, this study draws attention to the lack of high-quality RCTs and exclusion of cognitive function as an outcome measure in the research of sarcopenia. A comprehensive and sustained system including standardized sarcopenia screening, assessments of cognitive functioning, and evidence-based intervention programs is needed in order to prevent and manage sarcopenia amongst older adults in the community.

Third Parties' Reactions to Peer Abusive Supervision: An Examination of Current Research (비인격적 감독행위에 대한 제3자 반응 연구동향)

  • Kim, Moon Joung
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.1
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    • pp.175-190
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    • 2022
  • Abusive supervision occurs in a social context in which third-party observers react and interact with the abused victims and supervisors. Despite the importance of third-party observers' behavior in abusive supervision, research on abusive supervision has mainly focused on the dyadic relationship between direct victims and supervisors. Although in recent years research on third parties' reactions to peer abusive supervision has attracted growing attention, there are still insufficient studies examining the topic especially within domestic research in Korea. As such, this study comprehensively reviews empirical studies on third parties' reactions to peer abusive supervision and aims to broaden the scope of research in the field. Firstly, the results of previous studies show that the effects of observed peer abusive supervision are mediated by cognitive and affective processes. Secondly, previous studies are found to investigate the boundary conditions where the effects of observed peer abusive supervision can be amplified or mitigated with regard to various outcomes. Overall, compared to research on direct victims, research on third-party observers of abusive supervision is found to capture a wider spectrum of responses. In order to explain the mechanisms of this phenomena, this study thoroughly examines theoretical assumptions presented in previous studies and categorizes them into five theory types. Finally, this study identifies a couple of central methodological issues, including common method bias and inadequate model specification in the literature and suggests future research directions.

Punitiveness Toward Defendants Accused of Same-Race Crimes Revisited: Replication in a Different Culture (동인종 범죄로 기소된 피고인에 대한 엄벌주의적 판단의 재고찰: 다른 문화에서의 적용)

  • Lee, Jungwon;Khogali, Mawia;Despodova, Nikoleta M.;Penrod, Steven D.
    • Korean Journal of Forensic Psychology
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    • v.11 no.1
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    • pp.37-61
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    • 2020
  • Lee, Khogali, Despodova, and Penrod (2019) demonstrated that American participants whose races are different from a defendant and a victim rendered more punitive judgments against the defendant in a same-race crime (e.g., White observer-Black defendant-Black victim) compared to a cross-race crime (e.g., White observer-Black defendant-Hispanic victim). The aim of the current study was to test the replicability of their findings in a different country-South Korea. Study 1a failed to replicate the race-combination effect in South Korea with three new moderators-case strength, defendant's use of violence, and race salience. Study 1b was conducted with the same design of Study 1a in the United States to examine whether the failure of the replication in Study 1a was due to cultural differences between South Korea and the United States. However, Study 1b also failed to replicate the race-combination effect. Study 2 conducted a meta-analytic review of the data from Lee et al.'s (2019) study, along with the data from Study 1a and 1b and revealed that the race-salience manipulation in Study 1a and 1b might have caused the null results. We conclude that when people' races are different from both a defendant and a victim, they are likely to render more punitive judgments against the defendant in a same-race crime than a cross-race crime. However, the race-combination effect is only sustained when race-relevant issues are not salient in the crime.

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Effects of Exercise-Based Intervention Before and After Lung Cancer Surgery: A systematic review in pubmed database (허파암 수술 전과 후에 적용한 운동의 효과: PubMed 내 연구에 대한 체계적 문헌고찰)

  • Boram Oh;Heesu Kim;Sookyoung Park
    • Journal of The Korean Society of Integrative Medicine
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    • v.11 no.2
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    • pp.23-35
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    • 2023
  • Purpose : Lung cancer induces a decrease in physical activity and a deterioration of respiratory ability. Exercise is an effective treatment to reduce side effects of anti-cancer treatments, also influence the survival and successful rehabilitation in lung cancer patients. However, there is insufficient evidence to show which period is the most effective to apply exercise for lung cancer patients. Therefore, this study was conducted to evaluate the efficacy of exercise-based interventions before and after surgery. Methods : Clinical trials (CTs) and randomized controlled trials (RCTs) reported in PubMed database were investigated. The trials investigated in this study were published for 10 years before August 20, 2022. The risk of bias was judged according to the Cochrane guideline. The materials included in this meta-analysis were 6-minute walk test (6MWT), pulmonary function, and quality of life (QOL). Results : 1 CT and 9 RCTs were selected in current study. In the meta-analysis, exercise increased 6MWT in preoperation (mean difference [MD] 29.49; 95 % confidence interval [CI] .99 to 57.99; p=.04; I2=0 %), 3 months postoperation (MD 54.97; 95 % CI 31.85 to 78.09; p<.001; I2=45 %) and 6 months postoperation (MD 85.59; 95 % CI 45.06 to 126.12; p<.001; I2=47 %). Exercise, also enhanced the lung function such as FEV1/FVC (%) in postoperation (MD 7.64; 95 % CI 6.26 to 9.02; p<.001; I2=19 %). Additionally, exercise improved QOL, such as preoperative EORTC-QLQ-C30-LC13 in mental function (MD 3.21; 95 % CI .64 to 5.79; p=.01; I2=0 %) and postoperative SF-36 in mental component summary (MD 9.24; 95 % CI 4.94 to 13.54; p<.001; I2=0%). Conclusion : These results indicate that exercise-based intervention can elevate the ability to exercise and the mental componentof QOL within 3 months.

Electrical response of tungsten diselenide to the adsorption of trinitrotoluene molecules (폭발물 감지 시스템 개발을 위한 TNT 분자 흡착에 대한 WSe2 소자의 전기적 반응 특성 평가)

  • Chan Hwi Kim;Suyeon Cho;Hyeongtae Kim;Won Joo Lee;Jun Hong Park
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.33 no.6
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    • pp.255-260
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    • 2023
  • As demanding the detection of explosive molecules, it is required to develop rapidly and precisely responsive sensors with ultra-high sensitivity. Since two-dimensional semiconductors have an atomically thin body nature where mobile carriers accumulate, the abrupt modulation carrier in the thin body channel can be expected. To investigate the effectiveness of WSe2 semiconductor materials as a detection material for TNT (Trinitrotoluene) explosives, WSe2 was synthesized using thermal chemical vapor deposition, and afterward, WSe2 FETs (Field Effect Transistors) were fabricated using standard photo-lithograph processes. Raman Spectrum and FT-IR (Fourier-transform infrared) spectroscopy reveal that the adsorption of TNT molecules induces the structural transition of WSe2 crystalline. The electrical properties before and after adsorption of TNT molecules on the WSe2 surface were compared; as -50 V was applied as the back gate bias, 0.02 μA was recorded in the bare state, and the drain current increased to 0.41 μA with a dropping 0.6% (w/v) TNT while maintaining the p-type behavior. Afterward, the electrical characteristics were additionally evaluated by comparing the carrier mobility, hysteresis, and on/off ratio. Consequently, the present report provides the milestone for developing ultra-sensitive sensors with rapid response and high precision.

Korean psychopathy: Based on the Korean Psychopathy Assessment Tool Validation Research (한국형 사이코패시: 국내 사이코패시 평가도구 타당화 연구를 바탕으로)

  • Minseong Kang;Dong Gi Seo;Jonghan Sea
    • Korean Journal of Culture and Social Issue
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    • v.30 no.1
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    • pp.55-79
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    • 2024
  • The purpose of this study is to conduct an exploratory investigation into Korean psychopathy by synthesizing the results of prior domestic research on the validation of psychopathy assessment tools. Domestic research on the validation of psychopathy scales has been constrained by limited research methodologies, bias toward male subjects, and the application of inappropriate factor structures. Furthermore, although discrepancies between the original scale and the Korean scale were identified regarding the factor structures through in construct validity research, discussion on the concept of Korean psychopathy has been limited. As a result, this study compared 16 domestic papers on the validation of psychopathy assessment tools along with 9 international foreign papers that addressed the factor structure of each original scale. By comparing the derived factor structures, items assigned to each factor, and omitted items from each study, the characteristics of Korean psychopathy were explored. The findings revealed that Korean psychopathy is recognizable from materialism, machiavellianism, and antisocial behavior and impulsivity. This study holds significance in synthesizing the outcomes of current domestic psychopathy validation research and offers a conceptual foundation to help understand Korean psychopathy.

Estimation of the Spring and Summer Net Community Production in the Ulleung Basin using Machine Learning Methods (기계학습법을 이용한 동해 울릉분지의 봄과 여름 순군집생산 추정)

  • DOSHIK HAHM;INHEE LEE;MINKI CHOO
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.29 no.1
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    • pp.1-13
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    • 2024
  • The southwestern part of the East Sea is known to have a high primary productivity compared to those in the northern and eastern parts, which is attributed to nutrients supplies either by Tsushima Warm Current or by coastal upwelling. However, research on the biological pump in this area is limited. We developed machine learning models to estimate net community production (NCP), a measure of biological pump, with high spatial and time scales of 4 km and 8 days, respectively. The models were fed with the input parameters of sea surface temperature, chlorophyll-a, mixed layer depths, and photosynthetically active radiation and trained with observed NCP derived from high resolution measurements of surface O2/Ar. The root mean square error between the predicted values by the best performing machine model and the observed NCP was 6 mmol O2 m-2 d-1, corresponding to 15% of the average of observed NCP. The NCP in the central part of the Ulleung Basin was highest in March at 49 mmol O2 m-2 d-1 and lowest in June and July at 18 mmol O2 m-2 d-1. These seasonal variations were similar to the vertical nitrate flux based on the 3He gas exchange rate and to the particulate organic carbon flux estimated by the 234Th disequilibrium method. To expand this method, which produces NCP estimate for spring and summer, to autumn and winter, it is necessary to devise a way to correct bias in NCP by the entrainment of subsurface waters during the seasons.

Statistics of two-point correlation and network topology for Ly α emitters at z ≈ 2.67

  • Sungryong Hong;Arjun Dey;Kyoung-Soo Lee;Alvaro A Orsi;Karl Gebhardt;Mark Vogelsberger;Lars Hernquist;Rui Xue;Intae Jung;Steven L Finklestein;Sarah Tuttle;Michael Boylan-Kolchin
    • Monthly Notices of the Royal Astronomical Society
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    • v.483 no.3
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    • pp.3950-3970
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    • 2019
  • We investigate the spatial distribution of Ly α-emitting galaxies (LAEs) at z ≈ 2.67, selected from the NOAO Deep Wide-Field Survey, using two-point statistics and topological diagnostics adopted from network science. We measure the clustering length, r0 ≈ 4 h-1 Mpc, and the bias, bLAE = 2.2+0.2-0.1. Fitting the clustering with halo occupation distribution (HOD) models results in two disparate possibilities: (1) where the fraction of central galaxies is <1 per cent in haloes of mass >1012 M and (2) where the fraction is ≈20 per cent. We refer to these two scenarios as the 'Dusty Core Scenario' for Model#1, since most of the central galaxies in massive haloes are dead in Ly α emission, and the 'Pristine Core Scenario' for Model#2, since the central galaxies are bright in Ly α emission. Traditional two-point statistics cannot distinguish between these disparate models given the current data sets. To overcome this degeneracy, we generate mock catalogues for each HOD model using a high-resolution N-body simulation and adopt a network statistics approach, which provides excellent topological diagnostics for galaxy point distributions. We find three topological anomalies from the spatial distribution of observed LAEs, which are not reproduced by the HOD mocks. We find that Model#2 matches better all network statistics than Model#1, suggesting that the central galaxies in >1012 h-1 M haloes at z ≈ 2.67 need to be less dusty to be bright as LAEs, potentially implying some replenishing channels of pristine gas such as the cold mode accretion.

A Study on College Students' Perceptions of ChatGPT (ChatGPT에 대한 대학생의 인식에 관한 연구)

  • Rhee, Jung-uk;Kim, Hee Ra;Shin, Hye Won
    • Journal of Korean Home Economics Education Association
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    • v.35 no.4
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    • pp.1-12
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    • 2023
  • At a time when interest in the educational use of ChatGPT is increasing, it is necessary to investigate the perception of ChatGPT among college students. A survey was conducted to compare the current status of internet and interactive artificial intelligence use and perceptions of ChatGPT after using it in the following courses in Spring 2023; 'Family Life and Culture', 'Fashion and Museums', and 'Fashion in Movies' in the first semester of 2023. We also looked at comparative analysis reports and reflection diaries. Information for coursework was mainly obtained through internet searches and articles, but only 9.84% used interactive AI, showing that its application to learning is still insufficient. ChatGPT was first used in the Spring semester of 2023, and ChatGPT was mainly used among conversational AI. ChatGPT is a bit lacking in terms of information accuracy and reliability, but it is convenient because it allows students to find information while interacting easily and quickly, and the satisfaction level was high, so there was a willingness to use ChatGPT more actively in the future. Regarding the impact of ChatGPT on education, students said that it was positive that they were self-directed and that they set up a cooperative class process to verify information through group discussions and problem-solving attitudes through questions. However, problems were recognized that lowered trust, such as plagiarism, copyright, data bias, lack of up-to-date data learning, and generation of inaccurate or incorrect information, which need to be improved.