149 research outputs found

    Exploring Teacher Perceptions of Influential Facilitators of Elementary Mathematics Professional Development: A Mixed Methods Investigation

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    This dissertation examines the role of the facilitator in elementary mathematics professional development. An exploratory sequential mixed methods design was utilized to answer the central research question: How do United States elementary school teachers perceive an influential facilitator of elementary mathematics professional development (EMPD)? Phase one of this study explored teacher perceptions through a phenomenological design, which informed the second phase of the study, the implementation of a survey instrument to elementary school mathematics teachers on a larger scale. This dissertation is divided into six chapters. Chapter One presents a rationale for examining the role of the facilitator in professional development. Chapter Two builds on this rationale by synthesizing and discussing the current literature relating to professional development. Chapter Three examines the procedures used in each phase of the mixed methods research design. Within this examination are the specific sampling, data collection, and data analysis procedures that were used to investigate the central research question. Chapters Four and Five present the results of each phase of the research design and Chapter Six provides a discussion of these results with implications for future research

    A Play Bag Intervention: Bridging Home and School

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    With family involvement in early childhood education threatened by time constraints, the authors offer a dynamic solution for building relationships and fostering communication through take-home play bags

    HyFlex pedagogy: six strategies supported by design-based research

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    Purpose–This study investigates the following research question: What pedagogical strategies are necessary for the success of the project? The findings to this question are based in new media literacies and help to further pedagogy in an emerging HyFlex model while also grounding in needed theorization. Design/methodology/approach–This study uses design-based research(DBR) across two iterations and four doctoral, higher education courses, using mixed methods of data collection and analysis. Findings–Six pedagogical strategies influential for HyFlex research are presented, each grounded in a new media literacy skill. Originality/value–These six pedagogical strategies help practitioners grappling with the HyFlex or blended learning model merge traditional pedagogy with how this might be tailored for students entrenched in a participatory culture

    Development of a Moving Bed Reactor for Thermochemical Heat Storage Based on Granulated Ca(OH)2

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    Calcium hydroxide is promising for thermal energy storage due to its low cost and high energy density. Nevertheless, the powdered material is cohesive and has low thermal conductivity which is a major challenge for the operation of moving bed reactors. One approach to facilitate the movement of the reaction bed is the stabilisation of the particles through the coating of Ca(OH)2 granules with Al2O3 particles. In this work, a newly designed reactor concept was specifically developed for testing coated Ca(OH)2 granules. The design allows for the movement of the reaction bed by gravity assistance and direct heating of the particles by a counter current gas flow. The operation was successfully demonstrated and proved to achieve high heat transfer between gas and granules. Furthermore, the movement of the reaction bed was achieved after the discharging phase. Two batches of uncoated and coated Ca(OH)2 granules were subject of 10 thermochemical cycles in this reactor. The cycling stability, structural integrity, mechanical stability, morphology and phase composition of the granules were analysed. Full conversion of both samples was demonstrated for the entire experimental series. It was found that the alumina coating enhances the mechanical stability of the granules under reaction conditions

    Bildnachweis

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    Die Ausstellung „Osmanen in Hamburg – eine Beziehungsgeschichte zur Zeit des Ersten Weltkrieges“, die vom 6. November 2014 bis zum 4. Januar 2015 in der Staats- und UniversitĂ€tsbibliothek Carl von Ossietzky gezeigt wurde, widmete sich anlĂ€sslich des 100. Jahrestages der „Urkatastrophe“ den deutsch-osmanischen Beziehungen aus Hamburger Sicht und nahm vor allem die Zeit zwischen 1914 und 1918 in den Blick. Die erstmals gezeigten Archivmaterialien veranschaulichen dabei nicht nur die wirtschaftlichen, diplomatischen und kulturellen Kontakte. Sie vermitteln vor allem einen Eindruck von der PrĂ€senz und vom Leben der ethnisch wie religiös heterogenen Gruppe der Osmanen (u. a. Armenier, Griechen, sephardische Juden, muslimische TĂŒrken) in Hamburg, deren Spuren sich bis ins 19. Jahrhundert zurĂŒckverfolgen lassen. Der vorliegende Katalog möchte aber nicht nur die in acht Sektionen unterteilte Ausstellung dokumentieren. Er liefert mit zusĂ€tzlichen acht BeitrĂ€gen einen weiterfĂŒhrenden Einblick in die komplexe und ambivalente osmanisch-deutsche bzw. hamburgisch-osmanische Beziehungsgeschichte. In drei Kapiteln werden neben den transkulturellen Begegnungen wie Kulturdifferenzen der Zeit von etwa 1850 bis 1909, die kolonialen Ambitionen und orientalistischen Embleme des Deutschen Reiches, aber auch die Rolle deutscher Frauen im Osmanischen Reich zwischen 1914 und 1918 beleuchtet.The exhibition "Osmanen in Hamburg - a relationship history during the First World War" which was shown in the Hambrug State and University Library from November 6th, 2014 to January 4th, 2015, devoted itself to the 100th anniversary of the "Urkatastrophe" (the Great War) to he German-Ottoman relations from the perspective of Hamburg, and focused on the years between 1914 and 1918. The archival objects were presented for the first time and are documented in this publication. They illustrate not only economic, diplomatic and cultural contacts., but also give an impression of the presence and the life of the ethnically and religiously heterogeneous group of the Ottomans (e.g. Armenians, Greeks, Sephardic Jews, Muslim Turks) in Hamburg who can be traced back to the 19th century. This catalog, however, does not only want to document the exhibition which was divided into eight sections. With an additional eight contributions, it provides a deeper insight into the complex and ambivalent Ottoman-German and/ or Hamburg-Ottoman relations. In addition to transcultural encounters such as cultural differences between the time of 1850 and 1909 the colonial ambitions and oriental emblems of the German Reich, as well as the role of German women in the Ottoman Empire between 1914 and 1918, are illuminated in three chapters

    Technology-assisted stroke rehabilitation in Mexico: a pilot randomized trial comparing traditional therapy to circuit training in a Robot/technology-assisted therapy gym

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    Background Stroke rehabilitation in low- and middle-income countries, such as Mexico, is often hampered by lack of clinical resources and funding. To provide a cost-effective solution for comprehensive post-stroke rehabilitation that can alleviate the need for one-on-one physical or occupational therapy, in lower and upper extremities, we proposed and implemented a technology-assisted rehabilitation gymnasium in Chihuahua, Mexico. The Gymnasium for Robotic Rehabilitation (Robot Gym) consisted of low- and high-tech systems for upper and lower limb rehabilitation. Our hypothesis is that the Robot Gym can provide a cost- and labor-efficient alternative for post-stroke rehabilitation, while being more or as effective as traditional physical and occupational therapy approaches. Methods A typical group of stroke patients was randomly allocated to an intervention (n = 10) or a control group (n = 10). The intervention group received rehabilitation using the devices in the Robot Gym, whereas the control group (n = 10) received time-matched standard care. All of the study subjects were subjected to 24 two-hour therapy sessions over a period of 6 to 8 weeks. Several clinical assessments tests for upper and lower extremities were used to evaluate motor function pre- and post-intervention. A cost analysis was done to compare the cost effectiveness for both therapies. Results No significant differences were observed when comparing the results of the pre-intervention Mini-mental, Brunnstrom Test, and Geriatric Depression Scale Test, showing that both groups were functionally similar prior to the intervention. Although, both training groups were functionally equivalent, they had a significant age difference. The results of all of the upper extremity tests showed an improvement in function in both groups with no statistically significant differences between the groups. The Fugl-Meyer and the 10 Meters Walk lower extremity tests showed greater improvement in the intervention group compared to the control group. On the Time Up and Go Test, no statistically significant differences were observed pre- and post-intervention when comparing the control and the intervention groups. For the 6 Minute Walk Test, both groups presented a statistically significant difference pre- and post-intervention, showing progress in their performance. The robot gym therapy was more cost-effective than the traditional one-to-one therapy used during this study in that it enabled therapist to train up to 1.5 to 6 times more patients for the approximately same cost in the long term. Conclusions The results of this study showed that the patients that received therapy using the Robot Gym had enhanced functionality in the upper extremity tests similar to patients in the control group. In the lower extremity tests, the intervention patients showed more improvement than those subjected to traditional therapy. These results support that the Robot Gym can be as effective as traditional therapy for stroke patients, presenting a more cost- and labor-efficient option for countries with scarce clinical resources and funding. Trial registration ISRCTN98578807

    A Motif Unique to the Human Dead-Box Protein DDX3 Is Important for Nucleic Acid Binding, ATP Hydrolysis, RNA/DNA Unwinding and HIV-1 Replication

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    DEAD-box proteins are enzymes endowed with nucleic acid-dependent ATPase, RNA translocase and unwinding activities. The human DEAD-box protein DDX3 has been shown to play important roles in tumor proliferation and viral infections. In particular, DDX3 has been identified as an essential cofactor for HIV-1 replication. Here we characterized a set of DDX3 mutants biochemically with respect to nucleic acid binding, ATPase and helicase activity. In particular, we addressed the functional role of a unique insertion between motifs I and Ia of DDX3 and provide evidence for its implication in nucleic acid binding and HIV-1 replication. We show that human DDX3 lacking this domain binds HIV-1 RNA with lower affinity. Furthermore, a specific peptide ligand for this insertion selected by phage display interferes with HIV-1 replication after transduction into HelaP4 cells. Besides broadening our understanding of the structure-function relationships of this important protein, our results identify a specific domain of DDX3 which may be suited as target for antiviral drugs designed to inhibit cellular cofactors for HIV-1 replication

    The DEAD-box helicase DDX3X is a critical component of the TANK-binding kinase 1-dependent innate immune response

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    TANK-binding kinase 1 (TBK1) is of central importance for the induction of type-I interferon (IFN) in response to pathogens. We identified the DEAD-box helicase DDX3X as an interaction partner of TBK1. TBK1 and DDX3X acted synergistically in their ability to stimulate the IFN promoter, whereas RNAi-mediated reduction of DDX3X expression led to an impairment of IFN production. Chromatin immunoprecipitation indicated that DDX3X is recruited to the IFN promoter upon infection with Listeria monocytogenes, suggesting a transcriptional mechanism of action. DDX3X was found to be a TBK1 substrate in vitro and in vivo. Phosphorylation-deficient mutants of DDX3X failed to synergize with TBK1 in their ability to stimulate the IFN promoter. Overall, our data imply that DDX3X is a critical effector of TBK1 that is necessary for type I IFN induction
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