Effect of dimerization on the field-induced birefringence in ferrofluids

The magnetic-field-induced birefringence in a ferrofluid composed of spherical cobalt nanoparticles has been studied both experimentally and theoretically. The considerable induced birefringence determined experimentally has been attributed to the formation of chains of nanoparticles. The birefringence has been measured as a function of the external magnetic field and the volume fraction (f) of nanoparticles. It is quadratic in f as opposed to the Faraday effect, which is linear in f. Experimental results agree well with the theoretical model based on a simple density functional approach. For dilute solutions the experimental results can be explained by assuming that only dimers of nanoparticles are formed while the concentration of longer chains is negligible

The information infrastructure of knowledge-based economies in the years 1995–2010

Aim: The objective of this article is to make a brief presentation of the information infrastructure as one of the four pillars of the knowledge-based economy (KBE). It also attempts to construct (based on taxonomic methods and applying seven diagnostic variables) a synthetic measure for assessing the degree of the development of information infrastructures in 29 KBEs in the time period 1995–2010.Motivation: The work structure is subordinated to the so defined objective and comprises the introduction, overview, measurement and analysis of the level of the development of information infrastructure in KBEs, and a brief summary.Results: The results of the research obtained by the author allowed the creation of four rankings of the level of the development of information infrastructure in the 29 analysed KBEs and led to the formulation of the conclusion that in the time period 1995–2010 the average level of the development of information infrastructure in the 29 economies grew steadily (with the highest values noted in highly developed KBEs), and the range of variability decreased significantly

EKONOMETRYCZNY MODEL ZGODNY KURSU WALUTOWEGO EUR/PLN W LATACH 2000-2006

Przeprowadzone w niniejszym artykule badanie ekonometryczne służyło identyfikacji kluczowych determinantów kursu złotego (kształtowanego w ramach systemu typu floating) oraz pomiarowi ich wpływu na zmiany średniego kursu EUR/PLN w poszczególnych kwartałach lat 2000-2006. Analiza ta została oparta o koncepcję dynamicznego modelowania zgodnego w sensie Z. Zielińskiego

Trójkąt niespójnych rozwiązań systemowych a możliwe modyfikacje reżimu kursowego Polski w okresie przygotowywania się do przyjęcia euro

Głównym celem niniejszego artykułu jest próba odpowiedzi na pytanie, czy i w jakim zakresie polski reżim kursowy powinien zostać zmodyfikowany przed włączeniem złotego do mechanizmu ERM II tak, by kurs centralny waluty narodowej wobec euro był bliski optymalnemu pod względem wiarygodności i szeroko pojętej ekonomii. Możliwe rozwiązania (tj. ustanowienie izby walutowej, utrzymanie systemu kursu płynnego kierowanego lub pełne upłynnienie kursu złotego oraz wprowadzenie reżimu kursu stałego z pasmem wahań) przedstawiono w kontekście koncepcji tzw. niemożliwego do zaistnienia magicznego trójkąta Frankela (ang. triangle of impossibility). Dopełnieniem tej analizy jest tabelaryczne zestawienie dodatkowych przesłanek wyboru systemu kursowego

Jerzy Tomala: economist of growth and development

Motivation: The year 2018 was celebrated at the Faculty of Economic Sciences and Management of Nicolaus Copernicus University in Toruń, Poland as the 50th anniversary of the existence of the Faculty. To celebrate this jubilee, numerous conferences, debates, conventions and occasional meetings were organized. On the occasion of these events, people who contributed greatly to the development of the Faculty of Economic Sciences and Management in the area of science and didactics as well as in the organizational field were recalled and honoured. Undoubtedly, Professor Jerzy Tomala was one of them.Aim: The aim of this article is to present the biography of Professor Jerzy Tomala with special emphasis on his scientific accomplishments, international successes, as well as didactic and organizational achievements at the Faculty of Economic Sciences and Management of Nicolaus Copernicus University in Toruń, Poland.Results: During many years of his scientific work, Professor Jerzy Tomala became a scholar who was recognised both in Poland and internationally — first and foremost as an authority in the field of broadly understood macroeconomic problems of economic growth (with particular emphasis laid on the impact of investment, technological progress and efficiency of technical and economic relations on the long-term growth of national income) and in the area of economic policy of developed countries, mainly of the United States of America. His scientific interests also included the issue of full employment, the concept of a potential national product and educational policy. Professor Jerzy Tomala was invited to various study internships at renowned universities in the United States and to renowned scientific and teaching institutions in Western Europe. He also worked as a consultant of the World Bank, and his publications impacted some important decisions made by international organizations such as, for instance, OECD, the European Community, or the World Bank. For his achievements in the field of science, didactics and organizational work, Professor Jerzy Tomala received high state awards, prestigious awards of the Minister of Higher Education and the Rector of Nicolaus Copernicus University in Toruń, as well as numerous honours from his students and alumni

The Knowledge-based Economy as a Stage in the Development of the Economy

The major objective of this article to attempt to show the model of a knowledge-based economy (KBE) as a stage in social, economic and institutional transformation, which has already been reached by highly developed economies. The research problem considered is examined against the background of the concepts A. Toffler’s waves of civilization and, J.A. Schumpeter’s waves of innovation with the use of the elements of historical and comparative analyses. The introduction outlines the context, objectives and the reasons for taking up the topic. The main part of the article presents the process of the evolution of the economy from a model of the agrarian economy, through the industrial and service-based economies to the knowledge-based economy and describes in detail the three stages of advancement of the knowledge-based economy with corresponding metrics. The last paragraph of the article presents the conclusions drawn from the analyses

Perceived stress and coping skills in professional master's level athletic training students

Background: As athletic training education continues to expand, it is important to consider the amount of stress students experience and what coping skills they use to mitigate it. Although there is considerable research on athletic training students and perceived stress (PS), there are few studies related to students enrolled in professional master's programs (MAT) regarding stress.Methods: Cross-sectional design with current students in Commission on Accreditation of Athletic Training Education (CAATE) accredited MAT programs (males=42, females=99, age=23.42 ± 2.91 years). Program directors were asked to forward a link to students in their respective MAT programs. The survey included a brief demographics section (age, gender, year in school, learning model). Two surveys were included: The Perceived Stress Scale (PSS) (reliability a=0.78) to measure perceived stress (PS), and the Coping Orientation to Problem Experience (COPE) inventory (reliability a=0.73) to measure coping skills (CS). Means and standard deviations were calculated for the PSS and 15 subscales of the COPE. One-way ANOVA's were calculated for PSS utilizing demographic variables. Pearson correlation analysis was used to calculate most significant CS, and the impact of them.Results: A mean PSS score (24.84 ± 7.267) revealed a moderate level of PS in MAT students. ANOVA demonstrated increased PS in females, in comparison to males (F(1,139) =4.93, p=.03). Pearson correlation analysis established multiple significant coping skills. Age revealed positive correlations with positive reinforcement (r=0.168, p=0.05), active coping (r=0.25, p <0.01), and acceptance (r=0.25, p <0.01); and negative for PS (r= - 0.18, p=0.03). Gender revealed significant correlations for females in venting (r= -0.19, p=0.02), social support (r= -0.22, p <0.01), and emotional support (r= -0.20, p=0.02). Year 2 of schooling demonstrated a significant correlation with mental disengagement (r=0.25, p <0.01). Learning model presented significant correlations with venting (r=0.18, p <0.01) and mental disengagement (r= -0.171, p <0.05). Perceived stress demonstrated significant correlations with positive reinforcement (r= -0.25, p <0.01) mental disengagement (r=0.188, p <0.05), venting (r=0.36, p=0.00), active coping (r= -0.27, p=0.001), denial (r=0.25, p <0.01), behavioral disengagement (r=0.39, p=0.00), substance use (r=0.25, p <0.01), and planning (r= -0.30, p=0.00).Conclusions: Our data suggests that female MAT students experience more PS than males. As age increases, the use of constructive coping skills increases. However, overall, MAT students use CS that are more detrimental to stress. These results can assist students and professors in recognizing and using healthier alternatives to cope with stress

Can self-efficacy predict first year medical students' academic success?

Background: Self-efficacy (SE), the ability for an individual to believe in their own capabilities, has been connected to an individual's ability to succeed, deal with resistance and failures, and cope with challenges, all skills that are essential for competent physicians. SE has been found to have a positive impact on college student academic performance, but has not been evaluated in medical students. The purpose of this study was to measure first year medical students' SE and to determine what characteristics impacted their academic success in their first semester of medical school.Summary of Work: 61 (29 male, 32 female) first year medical students at a single osteopathic medical school were asked to complete the SE scale and additional demographics. Data was combined with undergraduate (UG) GPA, MCAT score, first semester GPA, and class rank. Basic descriptives, means, standard deviations, and Pearson correlation values were calculated.Summary of Results: Four variables were found to be significantly correlated with first semester GPA (level of athletic performance of UG r=.311, p=.015; number applications submitted r= -.414, p=.000; UG GPA r=.488, p=.000; science GPA r=.467, p=.000) and three with class rank (number applications r=.355, p=.005; UG GPA r= -.483, p=.000; science GPA r= -.495, p=.000). General SE was significantly correlated to the size of hometown (r=.256, p=.049).Discussion & Conclusions: This study determined that medical students' first semester academic success was better predicted by academic preparation rather than a student's self-efficacy. This is in contrast to current undergraduate literature that demonstrates a significant impact on GPA and retention. Self-efficacy may therefore be more applicable to astute clinical skills rather than pre-clinical academic performance.Take Home Message: While this study did not find SE to be a predictor of first year medical student academic performance, the ability to control thoughts, feelings, and actions in stressful situations is critical to overall success as a physician. Academic programs should seek out options to assess and improve these skills prior to entering the clinical setting