bluuebunny/crossref_metadata_2025 huggingface dataset:
Vitamin D Levels in Pregnant Women Living in the Khanty-Mansi Autonomous Okrug – Yugra
Authors:   Khanty-Mansiysk State Medical Academy, Astakhova Tat’yana Yu. ,   District Clinical Hospital
Published: February 2023

The purpose of this study was to assess vitamin D levels in pregnant women living in the Khanty-Mansi Autonomous Okrug – Yugra (Russia). Materials and methods. In the course of a cohort study during the period of 2019–2020, the level of 25(OH)D in the serum of 110 female residents of Khanty-Mansiysk was determined. The subjects were divided into two groups: nonpregnant (control) (n = 58) and pregnant (n = 52) women. Results. Both non-pregnant and pregnant (1st – 2nd trimesters) women living in the Khanty-Mansi Autonomous Okrug – Yugra showed low vitamin D levels: non-pregnant women, 21.3 ± 0.7 ng/ml; pregnant women in the 1st trimester, 20.6 ± 0.6 ng/ml; in the 2nd trimester, 19.2 ± 0.5 ng/ml; in the 3rd trimester, 18.4 ± 0.4 ng/ml. These levels are below the lower limit of physiologically optimal values. Pregnant women in the 2nd and 3rd trimesters had significantly lower concentrations of 25(OH)D compared to non-pregnant women. The hypovitaminosis we identified has a tendency to increase from the 1st to the 3rd trimester, as the mother’s vitamin D requirement steadily increases due to the intensive growth of the foetus’ bones. The average blood vitamin D level of pregnant women in the 3rd trimester was found to be 1.6 times lower than the lower limit of the reference range and 1.2 times lower than that in the control group. The results of the study indicate a need for systemic diagnostic, preventive and corrective measures that will eliminate vitamin D deficiency in women living in the Khanty-Mansi Autonomous Okrug – Yugra.
Correlation Between Ultrasound and Electrocardiographic Parameters of Intracardiac Haemodynamics Under Physical Load in Humans
Authors:   Syktyvkar State University named after Pitirim Sorokin, Irzhak Lev I. , Russkikh Nadezhda G. , Parshukova Aleksandra N.
Published: February 2023

The purpose of this article was to study the mechanism of reduction in stroke volume after intense physical activity (the Astrand effect). Materials and methods. The research involved 23 apparently healthy male students of Syktyvkar State University named after Pitirim Sorokin (age: 19 ± 1 years, body weight: 75 ± 13 kg, height: 177 ± 7 cm, body mass index: 24 ± 4 kg/m2). The physical load consisted of the Stange test (voluntary inspiratory breath-holding) and the Martinet test (squats to failure) performed simultaneously. The parameters of intracardiac haemodynamics were assessed using electrocardiography and ultrasonography. Results. We established that at rest, about 80 cm3 of blood passes through the mitral valve and the aortic valve in a cardiac cycle lasting on average about 0.30 s. Under physical load, the total blood flow volume through the mitral valve is reduced by 8 %, while through the aortic valve, by 15 %. The decrease in stroke volume under physical load, accompanied by an increase in heart rate, is due to a reduction in the TP segment of the electrocardiogram (diastole). The free blood flow (during diastole) from the left atrium through the mitral valve stops and the forced flow (during systole) starts, coinciding in time with the PQ interval (left atrial systole) on the electrocardiogram. Changes in the subjects’ parameters associated with the flow dynamics through the mitral valve and further through the aortic valve, as well as the processes in the TP segment (diastole) indicate that it is the shortened diastole during exercise that serves as the main link in the mechanism of all subsequent rearrangements of intracardiac haemodynamics. This study contributes to the understanding of the mechanism of the Astrand effect. Moreover, it demonstrated the dependence of the diastolic function of the ventricles on the volume of free blood flow (during diastole) through the mitral valve during the contraction of the TP segment according to the electrocardiographic data.
Relationship Between Vitamin D Level and Functional State of Patients with Osteoarthritis Aged 60–80 Years Living in Murmansk
Authors:   City Outpatient Clinic No. 2, Kashpanov Maksim D. , Popov Vladimir V. ,   Northern State Medical University, Novikova Irina A. ,   Northern State Medical University
Published: February 2023

The purpose of this paper was to identify the relationship between the level of vitamin D and the functional state parameters in older patients with osteoarthritis. Materials and Methods. The study involved 100 subjects (85 women and 15 men) aged between 60 and 80 years (mean age 69.03 ± 2.34 years) receiving treatment at outpatient facilities in Murmansk. The following research methods were used: questionnaire, clinical examination, X-Ray, and serum vitamin D testing. The radiographic stage of osteoarthritis and the degree of joint dysfunction were determined. We used the Age Is Not a Barrier Questionnaire, Hospital Anxiety and Depression Scale, Pain Visual Analogue Scale, Mini Nutrition Assessment Questionnaire, and SF-36 Quality of Life Questionnaire. Results. We found that 1/3 of the patients with osteoarthritis aged 60–80 years had vitamin D deficiency, while over 1/2 of them had vitamin D insufficiency. Patients with vitamin D deficiency were more likely to show signs of a risk of malnutrition than those with vitamin D insufficiency, as well as a more pronounced pain syndrome, higher radiographic stages of osteoarthritis and degrees of joint dysfunction, as well as higher rates of anxiety and depression, and lower quality of life. Quality of life was lower in patients with higher levels of anxiety and depression, as well as with a more pronounced radiographic stage of osteoarthritis. The results of this study indicate the advisability of including vitamin D in the combination therapy of osteoarthritis in patients aged 60–80 years.
Physiological Bases of Goal-Directed Fluid Therapy in Cardiac Surgery (Review)
Authors:   Northern State Medical University, Volkov Dmitriy A. ,   City Clinical Hospital No. 1 named after E.E. Volosevich, Kirov Mikhail Yu.
Published: February 2023

Goal-directed fluid therapy is a paradigm in perioperative medicine, which includes haemodynamic monitoring and individualized haemodynamic management in high-risk patients by means of fluid therapy. This approach has certain benefits compared with the traditional model of fluid therapy during the perioperative period of cardiac surgery. The required fluid volume can be hard to determine. Traditionally, fluid therapy was guided by static preload parameters, such as central venous pressure and pulmonary artery occlusion pressure, which failed to provide adequate precision. In opposition to static parameters, a number of dynamic indices and tests were developed to assess fluid responsiveness. The cornerstone of dynamic indices are cyclic preload changes due to intrathoracic pressure variations during mechanical ventilation. Dynamic tests are circulatory stress tests involving preload changes. The most frequently used tests are passive leg raise, fluid challenge test, and some others. However, in spite of their satisfactory predictive value, dynamic indices and tests have certain limitations, which must be taken into consideration. For instance, mechanical ventilation, sinus rhythm, intact thorax, and normal respiratory mechanics are obligatory conditions for applying dynamic indices. Thus, using dynamic indices can be difficult in cardiac surgery, making the search for new methods to overcome their limitations highly important.
The Nature of Total Power and Very Low Frequency Waves on the Interval Electrocardiogram from the Standpoint of the Human Body’s Adaptation to Motor Activity (Review)
Authors:   Vyatka State University, Kataev Denis A. ,   Tatarstan Cross-Country Skiing Federation, Tsirkin Viktor I. ,   Vyatka State University,   Kazan State Medical University, Kishkina Vlada V. ,   Vyatka State University,   City Clinical Hospital No. 1, Trukhina Svetlana I. ,   Vyatka State University, Trukhin Andrey N.
Published: February 2023

It is known that heart rate variability (HRV), evaluated using interval electrocardiography (ECG), reflects the influence of the autonomic nervous system (АNS) and biologically active substances on cardiac activity. For this reason, interval ECG method is widely used in sports, as it reveals the mechanisms of human adaptation to motor activity. This article analyses data on the median values of the total power (TP) of the HRV spectrum and absolute and relative power of very low frequency (VLF) waves on the interval electrocardiogram in athletes recorded in the supine position. We chose these three indicators out of more than 30 others due to their informativeness and due to the debatable issue of the nature of VLF waves. Literature data and unpublished results of our studies allow us to conclude that the values of these indicators in athletes depend on a number of factors, including type of sports (being especially high in sports building aerobic endurance), level of athletic skill (being maximum in elite athletes) as well as volume and intensity of training. In elite skiers, the values of these three indicators tend to change in the course of the training year, increasing in the preparatory phase, staying at a high level or even increasing during the competitive phase, and decreasing in the transition phase, which is determined by the relevant dynamics of the training volume throughout the year. The authors believe that the increase in the values of these three HRV indicators points to the growing influence of the parasympathetic division of ANS and non-neuronal acetylcholine on cardiac activity under heavy training volumes. According to the authors, the values of these three indicators reflect the level of aerobic motor activity (the higher they are, the higher this activity).
Destruction of the Aura of Art in Andy Warhol’s Works
Authors:   Kazan Innovative University named after V.G. Timiryasov, Yakovleva Elena L.
Published: February 2023

Since the 20th century, along with the introduction of innovations, society has seen the processes of ignoring/destroying/transforming the values of previous historical stages of development. The changes that have been taking place are controversial, which makes us investigate them in order to preserve/restore the best of the past. The sphere of art and the phenomenon of the aura of a work of art were chosen as the object of this research. The paper applies the phenomenological, analytical and biographical methods. They help to describe the phenomenon of the aura of a work of art, identify some of the reasons for its origination, reveal the causes of its disappearance/transformation in modern times and consider the situation on the basis of the philosophical and aesthetic position and works of the representative of pop art Andy Warhol. It should be noted that the aura is something difficult to comprehend. Originating in the process of creating a work of art, it (immaterially) manifests itself when the work is being perceived. The origins of the aura are traced to the author: due to his/her individual characteristics and creative resources, the work of art acquires its uniqueness and philosophical poetry. In modern conditions, the artist’s use of devices (audio/video and document-reproduction/digital) and technologies, as well as constant replication of art lead to the transformation or disappearance of the aura. The latter fact was pointed out as early as in 1936 by W. Benjamin. To illustrate this phenomenon, the paper studies the works of Andy Warhol, who actively used technology and various devices to create them. As a result, his pieces of art are devoid of the aura, their perception by the audience is alienated. Moreover, Warhol himself, having deliberately turned into a man-machine, felt no joy from the process. A similar analysis can be used to study other forms of art and creators. The results of the analysis will help in constructing the concept of the aura of art and describing this phenomenon, in understanding the transformation of the aura in contemporary works, as well as in finding ways to bring the aura to life in the creative process.
Ramón Cabrera on the Pages of the Newspaper Sankt-Peterburgskie Vedomosti in 1833−1840
Authors:   The Herzen State Pedagogical University of Russia, Tereshchuk Andrey A.
Published: February 2023

Through the prism of the publications in the Russian newspaper Sankt-Peterburgskie Vedomosti, this article studies the activities of General Ramón Cabrera, who took part in the First Carlist War in Spain (1833−1840). The conflict was motivated by the dynastic dispute between Don Carlos, one of the brothers of King Ferdinand VII of Spain, who died in 1833, and the widow, Queen Maria Christina, who defended the right of her daughter Isabella II to the throne. In the course of the conflict, Cabrera led the partisans of Don Carlos in the Maestrazgo, a historical area that included parts of modern Catalonia, Aragon, and Valencia. The period of 1838−1839 became the “golden age” of Carlism in the region. This paper analyses mentions Ramón Cabrera in Sankt-Peterburgskie Vedomosti between October 1833 and July 1840, i.e. throughout the conflict. A total of 1955 issues were studied, the war being mentioned in 1453 of them. The first mention of Cabrera in the newspaper dates back to 1834. However, the majority of the mentions were made during the final part of the conflict (1838−1840). In addition, the article provides examples of fake news, biographical paragraphs, and statements about the General by his comrades-in-arms. It is noted that some episodes of the war associated with Cabrera that later became widely known were only briefly touched upon in the newspaper. The General was a controversial figure in the eyes of his contemporaries, while Sankt-Peterburgskie Vedomosti took a neutral position on Cabrera.
Lend-Lease Armoured Vehicles in Operation Bagration (June 23 – August 29, 1944)
Authors:   Russian Arctic National Park, Khatanzeyskiy Aleksandr V.
Published: February 2023

This article dwells on the role of armoured vehicles obtained under the Lend-Lease agreement in the Byelorussian offensive operation (Bagration) in the summer of 1944. The author examines the use of foreign armoured vehicles in combat operations as part of tank, mechanized, and cavalry units of the Red Army and evaluates their quantity and quality. The Lend-Lease armoured vehicles participated in combat operations on all four fronts involved in Operation Bagration. Primarily, these were British Valentine Mk III and American M4A2 Sherman tanks. However, a significant contribution was also made by the SU-57 and M10 self-propelled artillery, as well as by the M3A1 Scout Car. In addition, the troops continued to use a certain number of M3 Medium and M3 Light tanks left over from the previous periods of the war. In 1944, they were no longer supplied. Foreign vehicles showed a good performance both in terms of reliability and combat qualities, in particular manoeuvrability, armour protection and firepower. Importantly, it was in the units advancing in the main direction that the number of Lend-Lease tanks was the largest (in the 1st Mechanized (100 %) and 3rd Guards Mechanized (91 %), in the 3rd Guards Cavalry (82.5 %) and in the 8th Guards Tank (59 %) Corps). In smaller numbers, foreign tanks were also available in the line units of all fronts involved in the operation (1st, 2nd and 3rd Byelorussian and 1st Baltic Fronts). In total, foreign tanks accounted for about 1/3 of the entire Soviet tank fleet in the Byelorussian offensive operation.
Maids, Batmen, Washerwomen and Other Servants in Russian Everyday Life at the Turn of the 20th Century
Authors:   Ryazan State University named for S.A. Yesenin, Popova Ol’ga D.
Published: February 2023

The article reviews a multi-authored monograph titled Domestic Servants in the Russian Empire in the Second Half of the 19th and Early 20th Centuries. The book comprehensively investigates the issue of domestic servants in post-reform Russia. It studies a great number of sources, contains interesting factual material and comes to some theoretical conclusions, as well as makes a serious contribution to understanding the social transformations in Russia. The review maintains that the investigated issues are highly relevant, since domestic service is in great demand in today’s Russia, though remaining as poorly regulated as it was in the early 20th century.
Demencija sergančių pacientų priežiūra pirminės sveikatos priežiūros grandyje
Authors: Lapiniauskaitė Julija , Margevičius Deividas , Baliutavičius Karolis
Published: February 2023

Tyrimo tikslas. Apibūdinti ir įvertinti šeimos gydytojų bei slaugytojų patirtį, prižiūrint vyresnio amžiaus pacientus, sergančius demencija. Tyrimo metodai. Atliktas kokybinis objekto tyrimas, naudojant vinjetės (klinikinių situacijų) metodą: informantams, susipažinus su konkrečia situacija, buvo pateikti penki struktūrizuoto interviu klausimai, leidžiantys numatyti medikų veiksmus ir bendradarbiavimą su kitų sričių specialistais. Gautų tyrimo duomenų analizei buvo naudotas teminės analizės metodas pagal Braun ir Clarke metodiką. Tyrimo dalyviai. Tiriamųjų imčiai nustatyti buvo taikyta kriterinė atranka. X rajone buvo atrinktos vyresnio amžiaus pacientus, sergančius demencija, prižiūrinčios medicinos įstaigos. Šiose įstaigose dirbantys gydytojai bei slaugytojai, prižiūrintys minėtus pacientus, sudarė visą tyrimo populiaciją, o tiriamųjų imtį – sveikatos priežiūros specialistai, savanoriškai sutikę dalyvauti tyrime. Tyrime dalyvavo 24 sveikatos priežiūros specialistai. Tyrimo rezultatai. Šeimos gydytojai ir slaugytojai, prižiūrintys vyresnio amžiaus pacientus, geba atpažinti bei diagnozuoti demenciją, tačiau jiems stinga patirties, numatant pacientų ilgalaikės priežiūros planą bei skiriant visavertį gydymą, pasiskirstant atsakomybes su kitų sričių specialistais.
Senyvo amžiaus pacientų, sergančių širdies ir kraujagyslių ligomis, griuvimų rizika. Rekomendacijos išplėstinės praktikos slaugytojams bendruomenėje
Authors: Spirgienė Lina , Burneikaitė Guoda , Kučikienė Odeta
Published: February 2023

Griuvimai – tai vienas iš senyvo amžiaus žmonių geriatrinių sindromų, kuriuos sukelia daugybė išorinių ir vidinių veiksnių. Griuvimų problema sprendžiama kompleksiškai, dalyvaujant interdisciplininei komandai, atliekant išsamų geriatrinį paciento tyrimą, aptariant prevencijos priemones, sudarant slaugos ir priežiūros planą.
Empirical Analysis on the Expansion of Renewable Power Generation: Focusing on KEPCO's Power Generation Subsidiaries
Authors:   The Korean Data Analysis Society, Kim Youngduk
Published: February 2023

Factors affecting the change in the amount of renewable power generation of KEPCO's power generation subsidiaries were empirically analyzed. For empirical analysis, a general power generation fuel demand model was established, and panel regression analysis was attempted using data from power generation subsidiaries for the period 2011-20. The empirical analysis results are summarized as follows. First, it is estimated that when the relative price of new and renewable power is high, the amount of renewable power is estimated to decrease. Second, renewable power generation has a substitute relationship with bituminous coal power generation and a complementary relationship with LNG power generation. have. Third, the RPS system directly and significantly played a leading role in increasing the amount of renewable power generation of power generation subsidiaries. Fourth, the emission trading system does not appear to have a significant effect on the increase in the amount of renewable power generation of power generation subsidiaries, which is why the emission trading system is not effective for renewable power generation. Fifth, the volatility of renewable power generation had a negative effect on the amount of renewable power generation as the supply of new and renewable power generation facilities increased. It can be inferred that as the amount of renewable power increases, the volatility of power generation increases, putting a burden on power generation subsidiaries.
Analysis on the Efficiency of the Korean Carbon Emissions Market: Comparison with the European Emissions Market
Authors:   The Korean Data Analysis Society, Choi Ki-Hong , Yoon Seong-Min
Published: February 2023

As the development of technologies that can reduce carbon emissions and the conversion of energy production methods have not produced particularly meaningful effects, major countries have high expectations for the effect of regulating the total amount of carbon emissions through the carbon emission market. Since Korea is a country that emits a lot of greenhouse gases, it operates a carbon emission market with a large transaction volume. For this market to show the expected effect, the movement of the emission permit price must be efficient. So this study analyzed whether the carbon emission market in Korea is efficient, comparing it with the European emission market. To this end, the time-varying Hurst exponent was measured using daily data of Korea's KAU and Europe's EUA Futures markets. The main results are summarized as follows. First, the degree of informational efficiency of the price movement of carbon emission market is time-varying. Second, in both the Korean and European carbon markets, transaction prices did not move randomly at many times, and there were many inefficient periods in both markets. Third, the long memory characteristics were stronger and the inefficiency was more severe in the KAU market than in the EUA market. Fourth, although the informational efficiency of KAU market has generally improved since 2022, it has not yet reached the level of efficiency implied by the efficient market hypothesis. These results mean that despite the government's efforts so far, the emission trading market is not functioning sufficiently. Therefore, it is necessary to continuously improve the emission trading system in a way that can reduce carbon emissions through the market function.
A Study on the Presenteeism by Company Size
Authors:   The Korean Data Analysis Society, Kwag Seon Hwa , Kim Mi Hee
Published: February 2023

This study aims to examine the presenteeism that reduces performance even though there is a disease, although it does not rest and goes to work is carried out. The purpose of this study was to confirm that the presenteeism of SMEs workers, in particular, according to the size of the company, appeared more than that of workers in large companies, and to confirm the effect of workers' health on work-family balance. This study examines the presenteeism of workers. First, there was a difference in presenteeism according to the size of the company. It was found that small and medium-sized enterprises with small businesses felt more presenteeism to workers. In this study, education level, age, and position were controlled, and it was found that workers at SMEs felt more presenteeism than workers at large companies. Second, the relationship between presenteeism and work-family balance felt by workers of used companies was stronger than that of large companies. In other words, it was found that the presenteeism of SMEs workers reduced the work-family balance further. This means that even though workers suffer from poor conditions, the job losses they experience from going to work without a break reduce the feeling that they have successfully achieved not only work but also the roles required in the home field. Finally, the significance and limitations of this study were discussed.
A Study on the Investment Alert Issues
Authors:   The Korean Data Analysis Society, Kim SungSin
Published: February 2023

This study examined the information effect on the disclosure date and the market's response for companies designated as investment alert during the period of April 2011 to November 2022. The results of the empirical analysis of this study are as follows. First, as a result of analyzing the difference in the average of major variables between investment alert companies and general KOSDAQ companies, the opacity of financial reports was significantly higher in investment alert companies than general KOSDAQ companies. The relatively high opacity suggests that the quality of profits is low and that earning management behavior is implemented using information asymmetry. Companies designated as investment alert had poor profitability and a relatively high debt ratio. In addition, the largest shareholder’s shares also decreased compared to the previous year. Second, according to the event study on the designation date of investment alert, the cumulative abnormal return (CAR) fell 19 days before the designation date, raising the possibility that prior information had already been leaked before the designation date. Third, according to the results of logistic regression analysis, the opacity of financial reports could predict the designation of investment alert in advance.
The Effects of Physical Self-Concept and self-Management on Satisfaction and Post-Activity Behavior of Social Sports Participants
Authors:   The Korean Data Analysis Society, Bae Young-Hoon
Published: February 2023

The purpose of this study is to popularize sports and expand the base by analyzing data on the effect of physical self-concept and self-management on satisfaction and post-activity behavior of social sports participants, and to provide important clues to researchers in the field of sports psychology. have. In order to achieve this purpose, as a result of a survey of 387 participants in social sports, the following conclusions were obtained. First, in the effect of physical self-concept on satisfaction and post-activity behavior of social and physical education participants, physical self-concept factors that affect satisfaction appeared as health, flexibility, and strength. Appearance, health, strength, and endurance were found to have an effect. Second, in the effect of self-management on satisfaction and post-activity behavior of social sports participants, the factors affecting self-management on satisfaction were body management and interpersonal management. Reparticipation intention was mental management, word of mouth intention was interpersonal. Management and mental management were found to have an effect.
Development and Validation of the Cyber Verbal Bullying Distress Scale
Authors:   The Korean Data Analysis Society, Heo Yea-Ji , Lee Jang-Han
Published: February 2023

The purpose of this study was to define a sub-concept of complex posttraumatic stress disorder (CPTSD) symptoms caused by cyber verbal bullying and to develop and validate the Cyber Verbal Bullying Distress Scale (CVBDS) which can measures the degree of the symptoms. For this purpose, the concept was set based on the literature review of CPTSD, PTSD, cyberbullying and interviews of 15 people who access cyber verbal bullying data and a total of 111 preliminary questions were selected. By verifying the facial and content validity, 71 questions were selected. 201 participants were collected to select the final items, and exploratory factor analysis, confirmatory factor analysis, higher-order confirmatory factor analysis was conducted in a row. As a result, a total of 30 items were extracted with the structure of 2-7 factors (PTSD: Intrusion, Arousal & Reactivity, Avoidance; DSO: Negative affect, Negative cognitions about the world and the others, Negative cognitions about the self, Disturbances in relationship). To find if cyber verbal bullying data had affected CPTSD symptoms, we conducted paired sample t-test using pre-post measurements and revealed that cyber verbal bullying data had influence on CPTSD symptoms. Through this study, it was proposed that the CVBDS can be used to measure CPTSD symptoms caused by cyber verbal bullying data as a reliable and valid measurement. This study could be provided as an important foundation for the study exploring symptoms and factor structures of CPTSD caused by cyber verbal bullying.
Analyses of tutoring activities via machine translation and NLP
Authors:   The Korean Data Analysis Society, Yoon Hae-Gyung , Kim Chulmin , Choi Seungbae , Kim Taeyoung
Published: February 2023

This is a follow-up study by Yoon, Kim, Choi, and Kim (2021). In the current study, the same text as the previous study was machine-translated into English, and then the topics derived through a statistical model, which were compared with the categories derived from the Korean text of the previous study. By doing this, rather than simply evaluating the quality of machine translation, the present study examined 1) the natural language processing model applied to text, 2) the role of human researchers in the process of interpreting the results after fitting the model, and 3) the harmony between human and machine translation, The texts to be analyzed were collected from the liberal arts education tutoring program of D university. A theoretical description of the Latent Dirichlet Allocation model, which is often used for topic modeling, and an explanation of the use of the R library ‘topicmodels’ were added. The analyses revealed a somewhat different pattern of topics from the previous study, and the authors’ interpretation was presented. Finally, while acknowledging the explosive growth of natural language processing and machine translation as a branch of it that cannot be reversed, the room for human translators to complement machine translation was suggested. This study presents a new approach to liberal arts education research by combining data analysis techniques using natural language processing and machine translation discussions.
The age effect of labor income by income quantile
Authors:   The Korean Data Analysis Society, Kwon Sanguk
Published: February 2023

Interpretation of estimates based on OLS(Ordinary Least Squared) method includes the concept of an average. Therefore, if the income equation is estimated by OLS, the difference in income between individuals is caused by the difference in explanatory variables, and the age effect controlled the effects of other explanatory variables is the same regardless of individual characteristics such as education level, living region, birth year etc. However, in related to empirical studies, the age effect differs depending on the level of education or birth year, and the age when income peaks varies. This implies that the age effect differs depending on individual characteristics and this motivation leads me to analyze age effect based on the quantile regression. For this study, I use workplace-based insured men with income information during more than 21 years in the national pension history data during 1988-2020. From the comparison on the age effect by income level, first, the higher income class, the higher age premium. Second, the age when income peaks is higher as the income level increases. Specifically, income peaks at age 40 for the bottom 10% of the income bracket, however, income peaks at age 50 for the upper 10% of the income bracket.
RHadoop-based Algorithm Utilizing QR Factorization for Multiple Linear Regression Analysis
Authors:   The Korean Data Analysis Society, Kang Minsu , Cho Sang-Hoon
Published: February 2023

RHadoop enables R users to perform big data analytics under R programming environment by integrating R with Hadoop that supports distributed storing and parallel processing of large-scaled data. This article proposes a RHadoop-based MapReduce programming model for estimating multiple linear regression models utilizing QR factorization. Our proposed algorithm accommodates the most common type of big data that has a vast number of data points with only a few hundred variables. For QR factorization over massive-scaled data, our algorithm employs DirectQR method proposed by Benson, Gleich, Demmel(2013); however, it does not necessitate its iterative steps to estimate regression coefficients. Through a comparative simulation study, our algorithm is compared with a MapReduce-based algorithm proposed in the previous studies. For generating realistic synthetic data, we utilize NYC(New York City) yellow taxi trip data reported to NYC Taxi and Limousine Commission. In the simulation, we measure estimation time and accuracy of each algorithm under several assumptions with respect to the strength of association between independent variables and the noise level of error terms in the regression models.
Motivation to Lead and Shared Leadership in Teams
Authors:   The Korean Data Analysis Society, Giraylar Zeynep , Choi Kyoosang
Published: February 2023

More companies have started to adopt a model of self-managed team as their primary work design. As work environments get more complex, an appointed leader alone cannot fulfill all the necessary leadership responsibilities of a team. In this manner, the shared leadership within a team is of great importance for today's work environments. The primary purpose of the present study was to examine an antecedent of shared leadership. Focusing on leadership motivation, this study investigated how team members’ motivation to lead affects shared leadership of the team. This study also examined the effects of shared leadership on team performance using an objective team performance measure, which little previous studies have investigated. Data were obtained from 57 teams consisting of 3 to 5 members. They performed a computer-based business strategy game. Findings showed that the teams consisting of members with a high level of motivation to lead scores were positively related to shared leadership and shared leadership significantly predicted team performance. Theoretical and practical implications of this study are also discussed.
A Research on ESG Commitment and Corporate Performance
Authors:   The Korean Data Analysis Society, Lee Jang Woo
Published: February 2023

ESG management matters ever more - globally. Firms, especially public firms are practically required to make investments in ESG. ESG investment is a way to satisfy social requirements on the one hand, but costs, on the other. Further, corporate governance is expected to affect the way ESG commitment is related to firm value. We test this idea using a data set of 3,943 firm-years from KRX from the years of 2011 to 2020. So we try to check what role ESG and corporate governance play in determining corporate market valuation in KRX market. We find that ESG commitment is mostly insignificantly, and sometimes negatively related to corporate market valuation. Again, ESG commitment in connection with governance in the form of chaebol affiliation is mostly significantly, and negatively related to corporate market valuation. So our research suggests that ESG commitment is currently not so much appreciated in KRX market, and that ESG investment with governance consideration is strongly likely to turn out with negatively significant effect on firm value. Why? It maybe because Korean firms, chaebol affiliated firms also, are not so much interested in ESG commitment yet. Lack of interest of firms leads to less ESG commitment, which, in turn, may call about lower evaluation of ESG activities in the market.
The visual attentional pattern toward smoking area signs in legal and illegal cigarette smokers: Preliminary findings
Authors:   The Korean Data Analysis Society, Kim Jaewon (Justine) , Lee Gi-Eun , Lee Jang-Han
Published: February 2023

Attentional patterns towards signs of smoking area might be different on individual levels. This would play a significant role in the decision-making process of illegal smoking behavior. In order to understand and effectively intervene the such behavior, this study aims to investigate the attentional pattern of the legal and illegal smokers toward the area signs (e.g. smoking area vs. no-smoking area) using a free viewing task and eye-tracking method. The participants were grouped into 25 legal smokers groups (LSG) and 15 illegal smokers groups (ISG) based on their usual smoking spots specified in the self-report questionnaire. During the free-viewing task where their visual attentional pattern was measured by an eye-tracking method, the participants were presented with eight pictorial stimuli with the area signs and the smoking-related cues. To examine the initial orientation process, the initial fixation latency, total dwell time, and dwell time by time blocks were analyzed for the smoking area signs. As a result, while LSG showed faster initial fixation toward the smoking area signs than no-smoking area signs, ISG did not. Also, LSG showed higher proportion of initial visual attention to smoking area signs. These findings suggest that the initial orienting attentional pattern of LSG toward the area signs might play a significant role in the legal smoking behavior.
Photometric Objects Around Cosmic Webs (PAC) Delineated in a Spectroscopic Survey. IV. High-precision Constraints on the Evolution of the Stellar–Halo Mass Relation at Redshift z < 0.7
Authors: Xu Kun , Jing Y. P. , Zheng Yun , Gao Hongyu
Published: February 2023

Taking advantage of the Photometric objects Around Cosmic webs method developed in Paper I, we measure the excess surface density

n

¯

2

w

p

of the photometric objects around spectroscopic objects down to stellar masses 108.0
M
⊙, 109.2
M
⊙, and 109.8
M
⊙ in the redshift ranges of z

s
< 0.2, 0.2 < z

s
< 0.4, and 0.5 < z

s
< 0.7, respectively, using data from the DESI Legacy Imaging Surveys and spectroscopic samples from the Sloan Digital Sky Survey (i.e., the Main, LOWZ, and CMASS samples). We model the measured

n

¯

2

w

p

in an N-body simulation, using the abundance matching method, and we constrain the stellar–halo mass relations (SHMRs) in the three redshift ranges to percent levels. With the accurate modeling, we demonstrate that the stellar mass scatter for a given halo mass is nearly a constant, and that the empirical form of Behroozi et al. describes the SHMR better than the double-power-law form at low mass. Our SHMR accurately captures the downsizing of massive galaxies from z

s
= 0.7, while it also indicates that small galaxies are still growing faster than their host halos. The galaxy stellar mass functions (GSMFs) from our modeling are in perfect agreement with the model-independent measurements in Paper III, although the current work extends the GSMFs to a much smaller stellar mass. Based on the GSMFs and the SHMRs, we derive the stellar mass completeness and halo occupation distributions for the LOWZ and CMASS samples, which are useful for correctly interpreting their cosmological measurements, such as galaxy–galaxy lensing and redshift space distortion.
Cyanopolyyne Chemistry in the L1544 Prestellar Core: New Insights from GBT Observations
Authors: Bianchi Eleonora , Remijan Anthony , Codella Claudio , Ceccarelli Cecilia , Lique Francois , Spezzano Silvia , Balucani Nadia , Caselli Paola , Herbst Eric , Podio Linda , Vastel Charlotte , McGuire Brett
Published: February 2023

We report a comprehensive study of the cyanopolyyne chemistry in the prototypical prestellar core L1544. Using the 100 m Robert C. Byrd Green Bank Telescope, we observe three emission lines of HC3N, nine lines of HC5N, five lines of HC7N, and nine lines of HC9N. HC9N is detected for the first time toward the source. The high spectral resolution (∼0.05 km s−1) reveals double-peak spectral line profiles with the redshifted peak a factor 3–5 brighter. Resolved maps of the core in other molecular tracers indicate that the southern region is redshifted. Therefore, the bulk of the cyanopolyyne emission is likely associated with the southern region of the core, where free carbon atoms are available to form long chains, thanks to the more efficient illumination of the interstellar field radiation. We perform a simultaneous modeling of the HC5N, HC7N, and HC9N lines to investigate the origin of the emission. To enable this analysis, we performed new calculation of the collisional coefficients. The simultaneous fitting indicates a gas kinetic temperature of 5–12 K, a source size of 80″, and a gas density larger than 100 cm−3. The HC5N:HC7N:HC9N abundance ratios measured in L1544 are about 1:6:4. We compare our observations with those toward the well-studied starless core TMC-1 and with the available measurements in different star-forming regions. The comparison suggests that a complex carbon chain chemistry is active in other sources and is related to the presence of free gaseous carbon. Finally, we discuss the possible formation and destruction routes in light of the new observations.
SN 2020uem: a Possible Thermonuclear Explosion within a Dense Circumstellar Medium. I. The Nature of Type IIn/Ia-CSM SNe from Photometry and Spectroscopy
Authors: Uno Kohki , Maeda Keiichi , Nagao Takashi , Nakaoka Tatsuya , Motohara Kentaro , Tajitsu Akito , Konishi Masahiro , Koyama Shuhei , Takahashi Hidenori , Tanaka Masaomi , Kuncarayakti Hanindyo , Kawabata Miho , Yamanaka Masayuki , Aoki Kentaro , Isogai Keisuke , Taguchi Kenta , Ogawa Mao , Kawabata Koji S. , Yoshii Yuzuru , Miyata Takashi , Imazawa Ryo
Published: February 2023

We have performed intensive follow-up observations of a Type IIn/Ia-CSM supernova (SN IIn/Ia-CSM), 2020uem, with photometry, spectroscopy, and polarimetry. In this paper, we report on the results of our observations focusing on optical/near-infrared (NIR) photometry and spectroscopy. The maximum V-band magnitude of SN 2020uem is less than −19.5 mag. The light curves decline slowly with a rate of ∼0.75 mag/100 days. In the late phase (≳300 days), the light curves show accelerated decay (∼1.2 mag/100 days). The optical spectra show prominent hydrogen emission lines and broad features possibly associated with Fe-peak elements. In addition, the Hα profile exhibits a narrow P-Cygni profile with an absorption minimum of ∼100 km s−1. SN 2020uem shows a higher Hα/Hβ ratio (∼7) than those of SNe IIn, which suggests a denser circumstellar medium (CSM). The NIR spectrum shows the Paschen and Brackett series with a continuum excess in the H and Ks bands. We conclude that the NIR excess emission originates from newly formed carbon dust. The dust mass (M
d) and temperature (T
d) are derived to be (M
d, T
d) ∼ (4−7 × 10−5
M
⊙, 1500–1600 K). We discuss the differences and similarities between the observational properties of SNe IIn/Ia-CSM and those of other SNe Ia and interacting SNe. In particular, spectral features around ∼4650 Å and ∼5900 Å of SNe IIn/Ia-CSM are more suppressed than those of SNe Ia; these lines are possibly contributed, at least partly, by Mg i] and Na i, and may be suppressed by high ionization behind the reverse shock caused by the massive CSM.
Modeling Hadronic Gamma-Ray Emissions from Solar Flares and Prospects for Detecting Nonthermal Signatures from Protostars
Authors: Kimura Shigeo S. , Takasao Shinsuke , Tomida Kengo
Published: February 2023

We investigate gamma-ray emission in the impulsive phase of solar flares and the detectability of nonthermal signatures from protostellar flares. Energetic solar flares emit high-energy gamma rays of GeV energies, but their production mechanism and emission site are still unknown. Young stellar objects, including protostars, also exhibit luminous X-ray flares, but the triggering mechanism of the flaring activity is still unclear owing to the strong obscuration. Nonthermal signatures in millimeter/submillimeter and gamma-ray bands are useful to probe protostellar flares owing to their strong penetration power. We develop a nonthermal emission model of the impulsive phase of solar flares, where cosmic-ray protons accelerated at the termination shock produce high-energy gamma rays via hadronuclear interaction with the evaporation plasma. This model can reproduce gamma-ray data in the impulsive phase of a solar flare. We apply our model to protostellar flares and show that the Cherenkov Telescope Array will be able to detect gamma rays of TeV energies if particle acceleration in protostellar flares is efficient. Nonthermal electrons accelerated together with protons can emit strong millimeter and submillimeter signals via synchrotron radiation, whose power is consistent with the energetic millimeter/submillimeter transients observed from young stars. Future gamma-ray and millimeter/submillimeter observations from protostars, coordinated with a hard X-ray observation, will unravel the nonthermal particle production and triggering mechanism of protostellar flares.
Low-frequency Gravitational-wave Memories from Gamma-Ray Burst Afterglows with Energy Injections
Authors: Huang Bao-Quan , Liu Tong , Xue Li , Qi Yan-Qing
Published: February 2023

Ultrarelativistic gamma-ray burst (GRB) jets are strong gravitational-wave (GW) sources with memory-type signals. The plateau (or shallow decay) phases driven by the energy injection may appear in the early X-ray afterglows of GRBs. In this paper, we investigate GW signals as well as X-ray afterglow emissions in the framework of GRB jets with energy injections, and both short- and long-duration GRBs are considered. We find that, regardless of the case, and because of the antibeaming and time delay effects, a rising slope that emerges in the waveform of the GW signal, due to the energy injection, lags far behind the energy ejection, and the typical frequencies of the characteristic amplitudes fall within a low-frequency region of ∼10−4–10−6 Hz; we also consider that the GW memories triggered by the GRB jets with energy injection have previously not been accounted for and that nearby GRBs with strong energy injections may disturb the measurement of the stochastic GW background. Such GW memory detection would provide a direct test for models of energy injection in the scenario of GRB jets.
Superhabitability of High-obliquity and High-eccentricity Planets
Authors: Jernigan Jonathan , Laflèche Émilie , Burke Angela , Olson Stephanie
Published: February 2023

Planetary obliquity and eccentricity influence climate by shaping the spatial and temporal patterns of stellar energy incident at a planet’s surface, affecting both the annual mean climate and magnitude of seasonal variability. Previous work has demonstrated the importance of both planetary obliquity and eccentricity for climate and habitability, but most studies have not explicitly modeled the response of life to these parameters. While exaggerated seasons may be stressful to some types of life, a recent study found an increase in marine biological activity for moderately high obliquities <45° assuming an Earth-like eccentricity. However, it is unclear how life might respond to obliquities >45°, eccentricities much larger than Earth’s, or the combination of both. To address this gap, we use cGENIE-PlaSim, a 3D marine biogeochemical model coupled to an atmospheric general circulation model, to investigate the response of Earth-like marine life to a large range of obliquities (0°–90°) and eccentricities (0–0.4). We find that marine biological activity increases with both increasing obliquity and eccentricity across the parameter space we considered, including the combination of high obliquity and high eccentricity. We discuss these results in the context of remote biosignatures, and we argue that planets with high obliquity and/or eccentricity may be superhabitable worlds that are particularly favorable for exoplanet life detection.
First penetration of pine processionary moth (Thaumetopoea pityocampa) in North Bulgaria
Authors: Georgiev Georgi , Georgieva Margarita , Mirchev Plamen , Belilov Sevdalin , Zaemdzhikova Gergana , Matova Maria
Published: February 2023

The pine processionary moth (Thaumetopoea pityocampa) was reported for the first time in North Bul-garia in 2022. Winter nests of the pest were observed in a number of pine plantations in more than 10 sites of four Forest State Enterprises (Troyan, Sevlievo, Gabrovo, Plachkovtsi). The penetration of the pest into the new localities is due to a long-distance dispersion by vehicles. In January 2023, the nests in new localities contained fifth-instar larvae of T. pityocampa. Only about 3% of them were empty as larvae had descended in the soil for pupation. Based on the high population density and presence of old nests in some localities, it was assumed that the pest penetrated into Northern Bulgaria most likely 3-4 years ago. 