401 research outputs found

    The effect of backpack load on trunk kinematics of imitated pathological gait: a case study

    Get PDF
    Background: It is well documented that loaded backpacks affect the biomechanics of gait in both children and adults. Minimal information is available with regard to the effects of backpacks on the biomechanics of gait in individuals with clinical gait abnormalities, such as those seen in cerebral palsy. Healthy, non-clinical populations can be taught how to ‘imitate’ typical gait abnormalities in order to study various experimental interventions without enlisting clinical patients. The objective of this study was to determine the acute effect of backpack load on kinematics of the trunk during typical and imitated pathological gait. Methods: COVID 19 restrictions precluded the use of multiple subjects as originally planned, therefore in response to those limitations only one healthy female (25 yrs) performed two trials each of 4 gait styles (typical, crouch, toe, and jump gait), under unloaded and backpack-loaded conditions. Trials were recorded and digitized using a 12-camera motion analysis system. The loaded conditions utilized a student backpack weighted at 20% of the participant’s body weight (11.8 kg) using various sized small weights. Kinematics of the trunk including mean lateral trunk tilt, mean trunk inclination and mean anterior-posterior pelvic tilt, along with select spatio-temporal variables, were compared across loading conditions and among each gait type. Results: The kinematic variables of trunk tilt and pelvic tilt were exaggerated under the loaded conditions across pathological gait patterns. Double support time increased while single support time decreased. Significance: This case-study investigation was conducted as a hypothesis-generating study for kinematic variables of the trunk under load in populations exhibiting the studied gait patterns. The findings warrant further research in reference to load carriage parameters. Electromyographic testing may be beneficial to add to the current test battery in order to capture additional compensatory muscle actions that may contribute to overall dynamic motor control of the participant. Future research should contribute to better informed carriage practices for individuals with pathological gait patterns seen in cerebral palsy and toe walking

    Nitrogen-related contrains of large-scale afforestation to sequester carbon: simulation study for climate change and management scenarios

    Get PDF
    Increase of forest areas has the potential to increase the terrestrial carbon (C) sink. However, the efficiency for C sequestration depends on the availability of nutrients such as nitrogen (N), which is affected by climatic conditions and management practices. In this study, I analyze how N limitation affects C sequestration of afforestation and how it is influenced by individual climate variables, increased harvest, and fertilizer application. To this end, JSBACH, the land component of the Earth system model of the Max Planck Institute for Meteorology is applied in idealized simulation experiments. In those simulations, large-scale afforestation increases the terrestrial C sink in the 21st century by around 100 Pg C compared to a business as usual land-use scenario. N limitation reduces C sequestration roughly by the same amount. The relevance of compensating effects of uptake and release of carbon dioxide by plant productivity and soil decomposition, respectively, gets obvious from the simulations. N limitation of both fluxes compensates particularly in the tropics. Increased mineralization under global warming triggers forest expansion, which otherwise is restricted by N availability. Due to compensating higher plant productivity and soil respiration, the global net effect of warming for C sequestration is however rather small. Fertilizer application and increased harvest enhance C sequestration as well as boreal expansion. The additional C sequestration achieved by fertilizer application is offset to a large part by additional emissions of nitrous oxide

    Academic and Non-Academic Factors Associated with Retention of Undergraduate College Students

    Get PDF
    The purpose of this study was to critically analyze both academic and nonacademic factors that may influence retention of health science students and the potential for future effective admission strategies beyond cognitive admission standards. The health science professions are fortunate to attract intelligent, competitive applicants to the professional programs. However, applicants may not possess the emotional intelligence skills to be interpersonally competent, caring healthcare providers. College institutions have only recently begun acknowledging the value of noncognitive criteria in admissions and student retention of beginning undergraduate students. The purpose of this correlational and comparative research study was to test a hypothesized model about students\u27 sociodemographic characteristics, emotional intelligence skills, and academic performance. A randomly selected sample of 109 undergraduate health science students in the College of Health and Human Services at Indiana University - Purdue University Fort Wayne (PEW) participated in this study. The online Emotional Quotient Inventory (EQ-i) research instrument and a researcher-designed online Student Profile sociodemographic questionnaire were used for this study. Results of psychometric analyses indicated estimates of reliability and validity related to the EQ-i. Respondents\u27 sociodemographic characteristics: gender, age, student enrollment status, class standing, and organizational and volunteer activity were predictive variables of their emotional intelligence skills. Male students scored higher on most of the emotional intelligence scales. Students\u27 34 to 45 years of age scored significantly higher in total EQ, stress management, and general mood scales. Students who were enrolled full-time had significantly higher total EQ scores than the students enrolled part-time. The students\u27 emotional intelligence scores were predictive variables with their academic performance (grade point average). Findings indicated students with high GPAs scored significantly higher in the following emotional intelligence scores: interpersonal, stress management, and impulse control skills. Structural equation modeling in future studies may further explain relationships in hypothesized models involving sociodemographic characteristics, emotional intelligence (noncognitive), and academic performance (cognitive) of undergraduate students. The generalizability and implications of results from studies measuring emotional intelligence of college students needs to be studied further. Additional research in this area is needed to determine whether health professions programs can directly influence future healthcare providers by using nonacademic factors

    Decoupling of the superconducting and magnetic (structural) phase transitions in electron-doped BaFe2As2

    Full text link
    Study and comparison of over 30 examples of electron doped BaFe2As2 for transition metal (TM) = Co, Ni, Cu, and (Co/Cu mixtures) have lead to an understanding that the suppression of the structural/antiferromagnetic phase transition to low enough temperature in these compounds is a necessary condition for superconductivity, but not a sufficient one. Whereas the structural/antiferromagnetic transitions are suppressed by the number of TM dopant ions (or changes in the c-axis) the superconducting dome exists over a limited range of values of the number of electrons added by doping (or values of the {a/c} ratio). By choosing which combination of dopants are used we can change the relative positions of the upper phase lines and the superconducting dome, even to the extreme limit of suppressing the upper structural and magnetic phase transitions without the stabilization of low temperature superconducting dome

    Physical and magnetic properties of Ba(Fe1−x_{1-x}Rux_x)2_2As2_2 single crystals

    Full text link
    Single crystals of Ba(Fe1−x_{1-x}Rux_x)2_2As2_2, x<0.37x<0.37, have been grown and characterized by structural, magnetic and transport measurements. These measurements show that the structural/magnetic phase transition found in pure BaFe2_2As2_2 at 134 K is suppressed monotonically by Ru doping, but, unlike doping with TM=Co, Ni, Cu, Rh or Pd, the coupled transition seen in the parent compound does not detectably split into two separate ones. Superconductivity is stabilized at low temperatures for x>0.2x>0.2 and continues through the highest doping levels we report. The superconducting region is dome like, with maximum Tc_c (∌16.5\sim16.5 K) found around x∌0.29x\sim 0.29. A phase diagram of temperature versus doping, based on electrical transport and magnetization measurements, has been constructed and compared to those of the Ba(Fe1−x_{1-x}TMx_x)2_2As2_2 (TM=Co, Ni, Rh, Pd) series as well as to the temperature-pressure phase diagram for pure BaFe2_2As2_2. Suppression of the structural/magnetic phase transition as well as the appearance of superconductivity is much more gradual in Ru doping, as compared to Co, Ni, Rh and Pd doping, and appears to have more in common with BaFe2_2As2_2 tuned with pressure; by plotting TS/TmT_S/T_m and TcT_c as a function of changes in unit cell dimensions, we find that changed in the c/ac/a ratio, rather than changes in cc, aa or V, unify the T(p)T(p) and T(x)T(x) phase diagrams for BaFe2_2As2_2 and Ba(Fe1−x_{1-x}Rux_x)2_2As2_2 respectively.Comment: 16 pages, 10 figure

    CEWA: An International, Interdisciplinary, Educational, Environmental Partnership

    Get PDF
    This chapter reports the international, interdisciplinary partnership that supports the Creative and Educational Welfare Affiliation (CEWA). We begin by describing CEWA, its various projects, and the genesis of the partnership that supports the CEWA card project. We describe the first year\u27s achievements as well as the difficulties with the CEWA card project. We conclude with recommendations for how to create successful international, interdisciplinary educational partnerships

    Effects of Co substitution on thermodynamic and transport properties and anisotropic Hc2H_{c2} in Ba(Fe1−x_{1-x}Cox_x)2_2As2_2 single crystals

    Full text link
    Single crystalline samples of Ba(Fe1−x_{1-x}Cox_x)2_2As2_2 with x<0.12x < 0.12 have been grown and characterized via microscopic, thermodynamic and transport measurements. With increasing Co substitution, the thermodynamic and transport signatures of the structural (high temperature tetragonal to low temperature orthorhombic) and magnetic (high temperature non magnetic to low temperature antiferromagnetic) transitions are suppressed at a rate of roughly 15 K per percent Co. In addition, for x≄0.038x \ge 0.038 superconductivity is stabilized, rising to a maximum TcT_c of approximately 23 K for x≈0.07x \approx 0.07 and decreasing for higher xx values. The T−xT - x phase diagram for Ba(Fe1−x_{1-x}Cox_x)2_2As2_2 indicates that either superconductivity can exist in both low temperature crystallographic phases or that there is a structural phase separation. Anisotropic, superconducting, upper critical field data (Hc2(T)H_{c2}(T)) show a significant and clear change in anisotropy between samples that have higher temperature structural phase transitions and those that do not. These data show that the superconductivity is sensitive to the suppression of the higher temperature phase transition

    Der Einfluss des Medienwandels auf Jugendliche und ihre IdentitÀtskonstruktion im Internet

    Get PDF
    Im Zentrum der wissenschaftlichen Auseinandersetzung steht der Einfluss des Medienwandels und der Medienkommunikation auf die IdentitĂ€tskonstruktion von Jugendlichen im Internet, wobei der Fokus auf Social-Media-Plattformen wie Facebook liegt. DarĂŒber hinaus sollte erforscht werden, inwieweit sich Jugendliche der Wirkungen und Folgen ihrer Darstellungen und IdentitĂ€tskonstruktionen im Internet bewusst sind, und welche VerĂ€nderungen im NutzerInnenverhalten ĂŒber einen Zeitraum von zwei Jahren ausgemacht werden können. Als Stichprobe diente eine Gruppe von SchĂŒlerinnen im Alter von 14-16 beziehungsweise (zum Zeitpunkt der zweiten Gruppendiskussion) 16-18 Jahren. Theorie Die Magisterarbeit wurde in zwei Theorieblöcke gliedert. Der erste Theorieteil bildet einen theoretischer Rahmen zu den fĂŒr die Arbeit relevanten Themen Gesellschaft und Medienwandel, in dem sowohl auf die Konstruktion von Wirklichkeitskonstruktion nach Siegfried J. Schmidt eingegangen wird, als auch auf aktuelle Überlegungen zur Kommunikation und Gesellschaft von Thomas A. Bauer. Ein weiterer Teil dieses TheoriebĂŒndels beschĂ€ftigt sich mit den fĂŒr die Arbeit zentralen Begriffen Media Literacy und Beobachtung und Beobachtungskompetenz, als auch mit Medienkompetenz. Im Mittelpunkt des zweiten Blocks stehen die fĂŒr die Arbeit essentiellen kommunikationswissenschaftlichen Theorien, die sich mit der Selbstdarstellung im Netz auseinandersetzen. Zentrale Begriffe sind an dieser Stelle die Social Presence Theorie und der Uses and Gratification Approach. Der Fokus liegt hierbei vor allem auf den Nutzungsmotiven der UserInnen, die durch den Uses and Gratification Approach erschlossen werden sollen. Ziel / Fragestellungen Die empirische Grundlage der Arbeit bilden zwei von der Autorin geleitete Gruppendiskussionen die in einem Abstand von zwei Jahren mit der identen Stichprobe durchgefĂŒhrt wurden. Ziel der Arbeit ist ein Herausarbeitung der vermuteten VerĂ€nderungen beziehungsweise Weiterentwicklungen sowohl im qualitativen als auch quantitativen Umgang der Stichprobe mit der Social-Media-Plattform Facebook. Es sollte sowohl der Wissenstand der Jugendlichen ĂŒber Möglichkeiten zum Schutz ihrer PrivatsphĂ€re auf Facebook, als auch der Umgang mit dieser erhoben werden. Ein weiterer Schwerpunkt liegt auf der pĂ€dagogischen Komponente der Nutzung von Internetplattformen. Hierbei wird der Lernfortschritt im Umgang der MĂ€dchen mit persönlichen Daten und deren allgemeine Medienkompetenz untersucht und hinterfragt. Ein weiterer Fokus wurde auf die Rollenverteilung zwischen Jugendlichen und deren Eltern und LeherInnen gelegt. Treten die Erwachsenen als Experten im Umgang mit Social-Media-Plattformen auf, oder sind es die Jugendlichen selbst, die diese den Eltern und LehrerInnen zugedachte Rolle einnehmen? Unter welchen Aspekten prĂ€sentieren sich die Jugendlichen online und wodurch wird diese IdentitĂ€tskonstruktion beeinflusst? Forschungsdesign FĂŒr den empirischen Teil der Arbeit wurde im Abstand von zwei Jahren (2010 und 2012) eine Panelforschung durchgefĂŒhrt. Als qualitatives Erhebungsinstrument entschied sich die Autorin fĂŒr eine Gruppendiskussion. Als BegrĂŒndung fĂŒr die Methodenwahl ist anzufĂŒhren, dass es nur wenige empirischen Ergebnisse zum Thema der vorliegenden Arbeit gibt, wodurch sich einerseits ein möglichst offenes Verfahren angeboten hat, andererseits der Versuch unternommen werden sollte, mit dem Verfahren kollektive Orientierungsmuster in denen sich ErfahrungsrĂ€ume dokumentieren, darzustellen. Ergebnisse Bereits im Theoriestudium wurde deutlich, dass es von einem methodologischem Standpunkt aus gesehen beinahe unmöglich ist, in der Social-Network-Forschung allgemeingĂŒltige Aussagen ĂŒber die kausalen ZusammenhĂ€nge der Social-Network-Nutzung und deren Folgen und Auswirkungen anzustellen. WĂ€hrend sich im studieren des aktuellen Forschungsstandes gezeigt hat, dass ein Großteil der UserInnen eine Vielzahl an persönlichen Informationen auf diversen Plattformen preisgibt, ohne genau zu wissen, wie BetreiberInnen der Online Plattformen diese Daten fĂŒr eigen Zwecke verwenden können, konnte diese These in der von der Autorin durchgefĂŒhrten Gruppendiskussion nicht bestĂ€tigt werden, da sich die Stichprobe sowohl ĂŒber den zu veröffentlichten Inhalt, als auch ĂŒber Maßnahmen zum Schutz selbiger, Gedanken gemacht hat. Dies wurde vor allem in den BemĂŒhungen deutlich, ihre persönlichen Daten durch PrivatsphĂ€reeinstellungen optimal zu schĂŒtzen. Es wurde ein durchaus reflektierter Umgang der MĂ€dchen mit ihren persönlichen Daten erkennbar. Eine mögliche ErklĂ€rung fĂŒr die Tatsache, dass die fĂŒr die Gruppendiskussion ausgewĂ€hlten Stichprobe, im Gegensatz zu der in der Literatur verbreiteten Meinung eines sehr unreflektierten Umgangs im Social Web , ĂŒber einen durchaus kompetenten Umgang mit ihren persönlichen Daten im Internet verfĂŒgt, kann der Umstand sein, dass die SchĂŒler der Stichprobe in einer sogenannten Laptop Klasse unterrichtet werden, in der das Internet und ein kritischer Umgang, vor allem mit persönlichen Daten Teil des Unterrichts ist . Des Weiteren konnten VerĂ€nderungen sowhol in der quantitativen Nutzung von Facebook (diese war RĂŒcklĂ€ufig) als auch in der qualitativen Nutzung festgetellt werden

    Online Trust and Health Information Websites

    Get PDF
    This study develops and tests a model of online trust of a health care website. The model showed a statistically strong fit to the data (N=176). Trust was significantly explained by perceptions of credibility, ease of use, and risk. Perceived ease of use was a direct predictor of trust and an indirect predictor through credibility. Credibility was both a direct predictor of trust and an indirect predictor through risk
    • 

    corecore