883 resultados para leadership in STEM


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Wood production represents a large but variable fraction of gross primary production (GPP) in highly productive Eucalyptus plantations. Assessing patterns of carbon (C) partitioning (C flux as a fraction of GPP) between above- and belowground components is essential to understand mechanisms driving the C budget of these plantations. Better knowledge of fluxes and partitioning to woody and non-woody tissues in response to site characteristics and resource availability could provide opportunities to increase forest productivity. Our study aimed at investigating how C allocation varied within one apparently homogeneous 90 ha stand of Eucalyptus grandis (W. Hill ex Maiden) in Southeastern Brazil. We assessed annual above-ground net primary production (ANPP: stem, leaf, and branch production) and total belowground C flux (TBCF: the sum of root production and respiration and mycorrhizal production and respiration), GPP (computed as the sum of ANPP, TBCF and estimated aboveground respiration) on 12 plots representing the gradient of productivity found within the stand. The spatial heterogeneity of topography and associated soil attributes across the stand likely explained this fertility gradient. Component fluxes of GPP and C partitioning were found to vary among plots. Stem NPP ranged from 554 g C m(-2) year(-1) on the plot with lowest GPP to 923 g C m(-2) year(-1) on the plot with highest GPP. Total belowground carbon flux ranged from 497 to 1235 g C m(-2) year(-1) and showed no relationship with ANPP or GPP. Carbon partitioning to stem NPP increased from 0.19 to 0.23, showing a positive trend of increase with GPP (R-2 = 0.29, P = 0.07). Variations in stem wood production across the gradient of productivity observed at our experimental site were a result of the variability in C partitioning to different forest system components.

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Isolation of mesenchymal stem cells (MSCs) from umbilical cord blood (UCB) from full-term deliveries is a laborious, time-consuming process that results in a low yield of cells. In this study we identified parameters that can be helpful for a successful isolation of UCB-MSCs. According to our findings, chances for a well succeeded isolation of these cells are higher when MSCs were isolated from UCB collected from normal full-term pregnancies that did not last over 37 weeks. Besides the duration of pregnancy, blood volume and storage period of the UCB should also be considered for a successful isolation of these cells. Here, we found that the ideal blood volume collected should be above 80 mL and the period of storage should not exceed 6 h. We characterized UCB-MSCs by morphologic, immunophenotypic, protein/gene expression and by adipogenic differentiation potential. Isolated UCB-MSCs showed fibroblast-like morphology and the capacity of differentiating into adipocyte-like cells. Looking for markers of the undifferentiated status of UCB-MSCs, we analyzed the UCB-MSCs' protein expression profile along different time periods of the differentiation process into adipocyte-like cells. Our results showed that there is a decrease in the expression of the markers CD73, CD90, and CD105 that correlates to the degree of differentiation of UCB-MSCs We suggest that CD90 can be used as a mark to follow the differentiation commitment degree of MSCs. Microarray results showed an up-regulation of genes related to the adipogenesis process and to redox metabolism in the adipocyte-like differentiated MSCs. Our study provides information on a group of parameters that may help with successful isolation and consequently with characterization of the differentiated/undifferentiated status of UCB-MSCs, which will be useful to monitor the differentiation commitment of UCB-MSC and further facilitate the application of those cells in stem-cell therapy.

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There have been almost fifty years since Harry Eckstein' s classic monograph, A Theory of Stable Democracy (Princeton, 1961), where he sketched out the basic tenets of the “congruence theory”, which was to become one of the most important and innovative contributions to understanding democratic rule. His next work, Division and Cohesion in Democracy, (Princeton University Press: 1966) is designed to serve as a plausibility probe for this 'theory' (ftn.) and is a case study of a Northern democratic system, Norway. What is more, this line of his work best exemplifies the contribution Eckstein brought to the methodology of comparative politics through his seminal article, “ “Case Study and Theory in Political Science” ” (in Greenstein and Polsby, eds., Handbook of Political Science, 1975), on the importance of the case study as an approach to empirical theory. This article demonstrates the special utility of “crucial case studies” in testing theory, thereby undermining the accepted wisdom in comparative research that the larger the number of cases the better. Although not along the same lines, but shifting the case study unit of research, I intend to take up here the challenge and build upon an equally unique political system, the Swedish one. Bearing in mind the peculiarities of the Swedish political system, my unit of analysis is going to be further restricted to the Swedish Social Democratic Party, the Svenska Arbetare Partiet. However, my research stays within the methodological framework of the case study theory inasmuch as it focuses on a single political system and party. The Swedish SAP endurance in government office and its electoral success throughout half a century (ftn. As of the 1991 election, there were about 56 years - more than half century - of interrupted social democratic "reign" in Sweden.) are undeniably a performance no other Social Democrat party has yet achieved in democratic conditions. Therefore, it is legitimate to inquire about the exceptionality of this unique political power combination. Which were the different components of this dominance power position, which made possible for SAP's governmental office stamina? I will argue here that it was the end-product of a combination of multifarious factors such as a key position in the party system, strong party leadership and organization, a carefully designed strategy regarding class politics and welfare policy. My research is divided into three main parts, the historical incursion, the 'welfare' part and the 'environment' part. The first part is a historical account of the main political events and issues, which are relevant for my case study. Chapter 2 is devoted to the historical events unfolding in the 1920-1960 period: the Saltsjoebaden Agreement, the series of workers' strikes in the 1920s and SAP's inception. It exposes SAP's ascent to power in the mid 1930s and the party's ensuing strategies for winning and keeping political office, that is its economic program and key economic goals. The following chapter - chapter 3 - explores the next period, i.e. the period from 1960s to 1990s and covers the party's troubled political times, its peak and the beginnings of the decline. The 1960s are relevant for SAP's planning of a long term economic strategy - the Rehn Meidner model, a new way of macroeconomic steering, based on the Keynesian model, but adapted to the new economic realities of welfare capitalist societies. The second and third parts of this study develop several hypotheses related to SAP's 'dominant position' (endurance in politics and in office) and test them afterwards. Mainly, the twin issues of economics and environment are raised and their political relevance for the party analyzed. On one hand, globalization and its spillover effects over the Swedish welfare system are important causal factors in explaining the transformative social-economic challenges the party had to put up with. On the other hand, Europeanization and environmental change influenced to a great deal SAP's foreign policy choices and its domestic electoral strategies. The implications of globalization on the Swedish welfare system will make the subject of two chapters - chapters four and five, respectively, whereupon the Europeanization consequences will be treated at length in the third part of this work - chapters six and seven, respectively. Apparently, at first sight, the link between foreign policy and electoral strategy is difficult to prove and uncanny, in the least. However, in the SAP's case there is a bulk of literature and public opinion statistical data able to show that governmental domestic policy and party politics are in a tight dependence to foreign policy decisions and sovereignty issues. Again, these country characteristics and peculiar causal relationships are outlined in the first chapters and explained in the second and third parts. The sixth chapter explores the presupposed relationship between Europeanization and environmental policy, on one hand, and SAP's environmental policy formulation and simultaneous agenda-setting at the international level, on the other hand. This chapter describes Swedish leadership in environmental policy formulation on two simultaneous fronts and across two different time spans. The last chapter, chapter eight - while trying to develop a conclusion, explores the alternative theories plausible in explaining the outlined hypotheses and points out the reasons why these theories do not fit as valid alternative explanation to my systemic corporatism thesis as the main causal factor determining SAP's 'dominant position'. Among the alternative theories, I would consider Traedgaardh L. and Bo Rothstein's historical exceptionalism thesis and the public opinion thesis, which alone are not able to explain the half century social democratic endurance in government in the Swedish case.

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Mesenchymale Stamzellen (MSC) sind Vertreter der adulten Stammzellen. Sie bergen durch ihre große Plastizität ein immenses Potential für die klinische Nutzung in Form von Stammzelltherapien. Zellen dieses Typs kommen vornehmlich im Knochenmark der großen Röhrenknochen vor und können zu Knochen, Knorpel und Fettzellen differenzieren. MSC leisten einen wichtigen Beitrag im Rahmen regenerativer Prozesse, beispielsweise zur Heilung von Frakturen. Breite Studien demonstrieren bereits jetzt auch bei komplexeren Erkrankungen (z.B. Osteoporose) therapeutisch vielversprechende Einsatzmöglichkeiten. Oft kommen hierbei aus MSC gezielt differenzierte Folgelinien aus Zellkulturen zum Einsatz. Dies bedingt eine kontrollierte Steuerung der Differenzierungsprozesse in vitro. Der Differenzierung einer Stammzelle liegt eine komplexe Veränderung ihrer Genexpression zugrunde. Genexpressionsmuster zur Erhaltung und Proliferation der Stammzellen müssen durch solche, die der linienspezifischen Differenzierung dienen, ersetzt werden. Die mit der Differenzierung einhergehende, transkriptomische Neuausrichtung ist für das Verständnis der Prozesse grundlegend und wurde bislang nur unzureichend untersucht. Ziel der vorliegenden Arbeit ist eine transkriptomweite und vergleichende Genexpressionsanalyse Mesenchymaler Stammzellen und deren in vitro differenzierten Folgelinien mittels Plasmid - DNA Microarrays und Sequenziertechniken der nächsten Generation (RNA-Seq, Illumina Plattform). In dieser Arbeit diente das Hausrind (Bos taurus) als Modellorganismus, da es genetisch betrachtet eine hohe Ähnlichkeit zum Menschen aufweist und Knochenmark als Quelle von MSC gut verfügbar ist. Primärkulturen Mesenchymaler Stammzellen konnten aus dem Knochenmark von Rindern erfolgreich isoliert werden. Es wurden in vitro Zellkultur - Versuche durchgeführt, um die Zellen zu Osteoblasten, Chondrozyten und Adipozyten zu differenzieren. Zur Genexpressionsanalyse wurde RNA aus jungen MSC und einer MSC Langzeitkultur („alte MSC“), sowie aus den differenzierten Zelllinien isoliert und für nachfolgende Experimente wo nötig amplifiziert. Der Erfolg der Differenzierungen konnte anhand der Genexpression von spezifischen Markergenen und mittels histologischer Färbungen belegt werden. Hierbei zeigte sich die Differenzierung zu Osteoblasten und Adipozyten erfolgreich, während die Differenzierung zu Chondrozyten trotz diverser Modifikationen am Protokoll nicht erfolgreich durchgeführt werden konnte. Eine vergleichende Hybridisierung zur Bestimmung differentieller Genexpression (MSC vs. Differenzierung) mittels selbst hergestellter Plasmid - DNA Microarrays ergab für die Osteogenese mit Genen wie destrin und enpp1, für die undifferenzierten MSC mit dem Gen sema3c neue Kandidatengene, deren biologische Funktion aufzuklären in zukünftigen Experimenten vielversprechende Ergebnisse liefern sollte. Die Analyse der transkriptomweiten Genexpression mittels NGS lieferte einen noch umfangreicheren Einblick ins Differenzierungsgeschehen. Es zeigte sich eine hohe Ähnlichkeit im Expressionsprofil von jungen MSC und Adipozyten, sowie zwischen den Profilen der alten MSC (eine Langzeitkultur) und Osteoblasten. Die alten MSC wiesen deutliche Anzeichen für eine spontane Differenzierung in die osteogene Richtung auf. Durch Analyse der 100 am stärksten exprimierten Gene jeder Zelllinie ließen sich für junge MSC und Adipozyten besonders Gene der extrazellulären Matrix (z.B col1a1,6 ; fn1 uvm.) auffinden. Sowohl Osteoblasten, als auch die alten MSC exprimieren hingegen verstärkt Gene mit Bezug zur oxidativen Phosphorylierung, sowie ribosomale Proteine. Eine Betrachtung der differentiellen Genexpression (junge MSC vs. Differenzierung) mit anschließender Pathway Analyse und Genontologie Anreicherungsstatistik unterstützt diese Ergebnisse vor allem bei Osteoblasten, wo nun jedoch zusätzlich auch Gene zur Regulation der Knochenentwicklung und Mineralisierung in den Vordergrund treten. Für Adipozyten konnte mit Genen des „Jak-STAT signaling pathway“, der Fokalen Adhäsion, sowie Genen des „Cytokine-cytokine receptor interaction pathway“ sehr spannende Einsichten in die Biologie dieses Zelltyps erlangt werden, die sicher weiterer Untersuchungen bedürfen. In undifferenzierten MSC konnte durch differentielle Genexpressionsanalyse die Rolle des nicht kanonischen Teils des WNT Signalweges als für die Aufrechterhaltung des Stammzellstatus potentiell äußerst einflussreich ermittelt werden. Die hier diskutierten Ergebnisse zeigen beispielhaft, dass besonders mittels Genexpressionsanalyse im Hochdurchsatzverfahren wertvolle Einblicke in die komplexe Biologie der Stammzelldifferenzierung möglich sind. Als Grundlage für nachfolgende Arbeiten konnten interessante Gene ermittelt und Hypothesen zu deren Einfluss auf Stammzelleigenschaften und Differenzierungsprozesse aufgestellt werden. Um einen besseren Einblick in den Differenzierungsverlauf zu ermöglichen, könnten künftig NGS Analysen zu unterschiedlichen Differenzierungszeitpunkten durchgeführt werden. Zudem wären weitere Anstrengungen zur erfolgreichen Etablierung der chondrogenen Differenzierung zur vollständigen Analyse der Genexpression des trilinearen Differenzierungspotentials von MSC wünschenswert.

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Background Increasing attention is being paid to improvement in undergraduate science, technology, engineering, and mathematics (STEM) education through increased adoption of research-based instructional strategies (RBIS), but high-quality measures of faculty instructional practice do not exist to monitor progress. Purpose/Hypothesis The measure of how well an implemented intervention follows the original is called fidelity of implementation. This theory was used to address the research questions: What is the fidelity of implementation of selected RBIS in engineering science courses? That is, how closely does engineering science classroom practice reflect the intentions of the original developers? Do the critical components that characterize an RBIS discriminate between engineering science faculty members who claimed use of the RBIS and those who did not? Design/Method A survey of 387 U.S. faculty teaching engineering science courses (e.g., statics, circuits, thermodynamics) included questions about class time spent on 16 critical components and use of 11 corresponding RBIS. Fidelity was quantified as the percentage of RBIS users who also spent time on corresponding critical components. Discrimination between users and nonusers was tested using chi square. Results Overall fidelity of the 11 RBIS ranged from 11% to 80% of users spending time on all required components. Fidelity was highest for RBIS with one required component: case-based teaching, just-in-time teaching, and inquiry learning. Thirteen of 16 critical components discriminated between users and nonusers for all RBIS to which they were mapped. Conclusions Results were consistent with initial mapping of critical components to RBIS. Fidelity of implementation is a potentially useful framework for future work in STEM undergraduate education.

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An international graduate teaching assistant‘s way of speaking may pose a challenge for college students enrolled in STEM courses at American universities. Students commonly complain that unfamiliar accents interfere with their ability to comprehend the IGTA or that they have difficulty making sense of the IGTA‘s use of words or phrasing. These frustrations are echoed by parents who pay tuition bills. The issue has provoked state and national legislative debates over universities‘ use of IGTAs. However, potentially productive debates and interventions have been stalemated due to the failure to confront deeply embedded myths and cultural models that devalue otherness and privilege dominant peoples, processes, and knowledge. My research implements a method of inquiry designed to identify and challenge these cultural frameworks in order to create an ideological/cultural context that will facilitate rather than impede the valuable efforts that are already in place. Discourse theorist Paul Gee‘s concepts of master myth, cultural models, and meta-knowledge offer analytical tools that I have adapted in a unique research approach emphasizing triangulation of both analytic methods and data sites. I examine debates over IGTA‘s use of language in the classroom among policy-makers, parents of college students, and scholars and teachers. First, the article "Teach Impediment" provides a particularly lucid account of the public debate over IGTAs. My analysis evidences the cultural hold of the master myth of monolingualism in public policy-making. Second, Michigan Technological University‘s email listserve Parentnet is analyzed to identify cultural models supporting monolingualism implicit in everyday conversation. Third, a Chronicle of Higher Education colloquy forum is analyzed to explore whether scholars and teachers who draw on communication and linguistic research overcome the ideological biases identified in earlier chapters. My analysis indicates that a persistent ideological bias plays out in these data sites, despite explicit claims by invested speakers to the contrary. This bias is a key reason why monolingualism remains so tenaciously a part of educational practice. Because irrational expectations and derogatory assumptions have gone unchallenged, little progress has been made despite decades of earnest work and good intentions. Therefore, my recommendations focus on what we say not what we intend.

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Fehlende Grundkenntnisse in der Mathematik zählen zu den größten Hindernissen für einen erfolgreichen Start in ein Hochschulstudium. Studienanfänger in einem MINT-Studium bringen inzwischen deutlich unterschiedliche Vorrausetzungen mit: „Mathe-Angst“ gilt als typisches Phänomen und der Übergang in ein selbstbestimmtes Lernverhalten stellt eine große Herausforderung dar. Diese Fall-Studie beschreibt, wie mit Hilfe einer Mathe-App bereits zu Beginn des Studiums aktives Lernen unterstützt und selbstbestimmtes Lernen eingeübt werden kann. Das neue Kurskonzept mit App-Unterstützung stößt an der Hochschule Offenburg auf breite Akzeptanz. Der mobile BYOD-Ansatz ermöglicht Lern-Szenarien, die über PC- bzw.- Laptop-gebundene eLearning-Lösungen nicht realisierbar sind. Der Inhalt des MassMatics-Vorbereitungskurs orientiert sich am Mindestanforderungskatalog des cosh-Arbeitskreises für den Übergang Schule-Hochschule. In der Zwischenzeit wurde der App-gestützte Kurs mit seinen über 500 Aufgaben von mehr als 1000 Studierenden besucht.

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Today, Digital Systems and Services for Technology Supported Learning and Education are recognized as the key drivers to transform the way that individuals, groups and organizations “learn” and the way to “assess learning” in 21st Century. These transformations influence: Objectives - moving from acquiring new “knowledge” to developing new and relevant “competences”; Methods – moving from “classroom” based teaching to “context-aware” personalized learning; and Assessment – moving from “life-long” degrees and certifications to “on-demand” and “in-context” accreditation of qualifications. Within this context, promoting Open Access to Formal and Informal Learning, is currently a key issue in the public discourse and the global dialogue on Education, including Massive Open Online Courses (MOOCs) and Flipped School Classrooms. This volume on Digital Systems for Open Access to Formal and Informal Learning contributes to the international dialogue between researchers, technologists, practitioners and policy makers in Technology Supported Education and Learning. It addresses emerging issues related with both theory and practice, as well as, methods and technologies that can support Open Access to Formal and Informal Learning. In the twenty chapters contributed by international experts who are actively shaping the future of Educational Technology around the world, topics such as: - The evolution of University Open Courses in Transforming Learning - Supporting Open Access to Teaching and Learning of People with Disabilities - Assessing Student Learning in Online Courses - Digital Game-based Learning for School Education - Open Access to Virtual and Remote Labs for STEM Education - Teachers’ and Schools’ ICT Competence Profiling - Web-Based Education and Innovative Leadership in a K-12 International School Setting are presented. An in-depth blueprint of the promise, potential, and imminent future of the field, Digital Systems for Open Access to Formal and Informal Learning is necessary reading for researchers and practitioners, as well as, undergraduate and postgraduate students, in educational technology.

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Im Jahr 1866 verfasste der damals in Breslau lehrende römisch-katholische Kirchenhistoriker Joseph Hubert Reinkens eine der ersten historisch-kritischen Studien in deutscher Sprache über Martin von Tours, in der er sich u.a. mit Martins bischöflichem Leitungsdienst befasste. Nach dem Ersten Vatikanischen Konzil (1870) wurde Reinkens 1873 der erste Bischof für die Alt-Katholiken im Deutschen Reich. Der Beitrag beschreibt den Einfluss, den Reinkens' Martin-Rezeption auf sein theologisches und praktisches Verständnis des Bischofsamts hatte.

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One of the major challenges in treating mental illness in Nigeria is that the health care facilities and mental health care professionals are not enough in number or well equipped to handle the burden of mental illness. There are several barriers to treatment for individual Nigerians which include the following: such as the lack of understanding of the root causes of mental illness, lack of financial support to get mental treatment, lack of social support (family, friends, neighbors), the fear of stigmatization concerning being labeled as mentally ill or being in association with the mentally ill, and the consultation of traditional native healers who may be unknowingly prolonging illness, rather than addressing and treating them due to lack of formal education and standardization of their treatments. Another barrier is the non-health nature of the mental health services in Nigeria. Traditional healers are essentially the mental health system. The elderly, women, and children are the most vulnerable groups in times of strife and hardships. Their mental well-being must be taken into account as well as their special needs in times of personal or societal crisis. ^ Nigerian mental health policy is geared toward forming a mental health system, but in actuality only a mental illness care system is the observed result of the policy. The government of Nigeria has drafted a mental health policy, yet its actual implementation into the Nigerian health infrastructure and society waits to be materialized. The limited health legislation or policy implementations tend to favor those who have access to these urban areas and the facilities' health services. Nigerians living in rural areas are at a disadvantage; many of them may not even be aware of services available to help them understand and treat mental illness. Perhaps, government driven health interventions geared toward mental illness in rural areas would reach an underserved Nigerians and Africans in general. Issues with political instability and limited infrastructure often hinder crucial financial resources and legislation from reaching the people that are truly in need of governmental leadership in regards to mental health policy.^ Traditional healers are a severely untapped resource in the treatment of mental illness within the Nigerian population. They are abundant within Nigerian communities and are meeting a real need for the mentally ill. However, much can be done to remove the barriers that prevent the integration of traditional healers within the mental health system and improve the quality of care they administer within the population. Mental illness is almost exclusively coped with through traditional medicine practices. Mobilization and education from each strata of Nigerian society and government as well as input from the medical community can improve how traditional medicine is utilized as a treatment for clinical illness and help alleviate the heavy burden of mental illness in Nigeria. Currently, there is no existing policy making structure for a working mental health system in Nigeria, and traditional healers are not taken into account in any formulation of mental health policy. Advocacy for mental illness is severely inadequate due to fear of stigmatization, with no formally recognized national of regional mental health association.^

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Kelly and Halverson are to be congratulated on their contribution to the field of education. Their efforts in designing The Comprehensive Assessment of Leadership forLearning (CALL) represents a step forward inm the fomative assessment of distributed leadership in schools and their work is noteworthy in its rapid linking of survey assessment data to specific feedback and recommendations for users. Issues relevant to evidence-based practices, implementation, and professional common language are addressed in this commentary.