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

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

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

Patient perceptions in receiving LGBTQIA culturally competent health care

Background: There is a large amount of documented evidence demonstrating that health care providers are caring for diverse populations. This warrants a level of cultural competence (CC) when making health care decisions. Traditionally, Race and ethnicity have been the focus in CC. However, criteria such as sexual orientation and gender identity are often forgotten, or left out altogether. Because of this, patients whose sexual orientation or gender is a minority, may often receive inadequate treatment. This is in part due to the health care providers lack knowledge in this type of CC or present sexual prejudices. Because of this, research is needed to investigate the perceptions of patients that identify as lesbian, gay, bisexual, transgender, queer/questioning, intersex, ally (LGBTQIA) when receiving health care.Methods: Cross-sectional design consisting of 140 participants (male=78, female=50, transgender=5, other=7; heterosexual=16, gay/lesbian=72, bisexual=43, other=9, mean age=26.97 ± 7.67). Participants were recruited using a snowball sampling method via email and list-serves. A modified version of the Gay Affirmative Practice (GAP) (reliability a = 0.962), was delivered online to participants to determine need of LGBTQIA cultural competent treatment by health care providers. Means and standard deviations were calculated for each variable (gender, sexual orientation), as well as an overall GAP score (out of 150). Two, single one-way ANOVAs (gender and sexual orientation) were performed with GAP score as the dependent variable.Results: Calculated GAP scores: All=128.82 ± 18.48, male=128.49 ± 15.60, female=130.35 ± 17.10, transgender=129.80 ± 9.31, other=143. 57, heterosexual=129.33 ± 17.12, gay or lesbian=128.25 ± 15.85, bisexual/omni/pansexual/queer/non-monosexual=132.79 ± 14.99, other=131.38 ± 20.37. ANOVA results were modified with Kruskal-Wallis adjustments due to violation of normality and homogeneity of variance, and now are represented by Chi Squares. Gender was the single significant outcome, (X2(3) =8.01, p <0.05). Post hoc testing of gender demonstrated statistical significant in comparing males vs. other.Conclusions: Patients do find it necessary for health care providers to have specific training and/or knowledge in LGBTQIA CC. A majority of results demonstrate strongly agree that health care providers need better CC in LGBTQIA. In comparison of GAP scores in gender, the category of other demonstrates a great need for CC in LGBTQIA in health care providers. Males demonstrated a much lower score, indicating a low priority for LGBTQIA CC in health care. With an increasing LGBTQIA patient population, patients feel the ever increasing need for health care providers to provide knowledgeable, competent, and fair treatment/care

Health behaviors in athletic trainers

Introduction: Athletic trainers (ATs) are healthcare professionals that care for the physically active. Because of this, it is estimated that ATs are healthy. Numerous research studies have demonstrated the benefit of health role-modeling and the beneficial effects it has on patients, but currently there is not data relating to ATs. This research explores the health behaviors that ATs demonstrate and what it means for patients.Methods: A pilot study was first used to determine reliability. Following the pilot, a quantitative study was conducted through a self-report survey sent to a specific pool of members in the National Athletic Trainers Association (NATA). It measured body measurement index (BMI), physical activity (PA), diet, weight-loss dieting behavior, disordered eating behavior, and work ability.Participants: 265 ATs (main study) met inclusion criteria for participation.Analysis: Data was analyzed based on research question. The first asked differences between BMI, PA, and nutrition by gender, years certified, setting, and region. Analyses of variance were used to determine differences. The second used chi square test to determine differences in dieting behavior between the same demographics in research question one, and then if disordered eating patterns related with that dieting behavior. The third used ordinal regression to predict differences in work ability (physical and mental), through BMI, gender, years certified, region, and type of work.Results: Question one demonstrated significance with gender and BMI, and light PA and setting. Females had a lower BMI than males, but no differences were observed with setting due to low power. The second question also demonstrated significance with: "Have you dieted?" and females, "how long have you kept the weight off?" and greater than 20 years certified, "are you currently on a diet?" and a greater disordered eating score, "have you ever dieted?" and a greater disordered eating score, and "how long did you keep the weight off?" and a greater disordered eating score.Conclusion: Though ATs may work with a physically active population, they appear to be "cutting corners" when it comes to their own health. This may reflect poorly on patient adherence and health due to poor health role-modeling