183 research outputs found

    The Star : A Fragment From Plato

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    https://digitalcommons.library.umaine.edu/mmb-vp/6046/thumbnail.jp

    PNL20 UTILIZATION OF IMMUNOMODULATORY DRUG THERAPIES IN MULTIPLE SCLEROSIS (MS) IN NOVA SCOTIA, CANADA 1998—2003

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    Digital storytelling as a disciplinary literacy enhancement tool for EFL students

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    This research compared the process of disciplinary literacy acquisition of students who experienced two different pedagogical approaches to learning science, technology, engineering and mathematics through astronomy (STEM-A). The objective of this study was to explore the impact of a digital storytelling (DST) educational technology intervention in a STEM-A context on the process of disciplinary literacy acquisition of students who were learning English as a foreign language (EFL). The research was designed as a type IV case study with a sample of 30 students from Kyrgyzstan aged between 12 and 16 years. Data were collected from written responses to the astronomy diagnostic tests (ADT), which were coded against the structure of the observed learning outcomes (SOLO) and analysed using the analysis of variance (ANOVA) with repeated measures on the occasion of testing. Data from the Australian sample, native speakers of English, (N = 328) were used as a baseline. The results showed a positive effect of the DST intervention on EFL students’ astronomy disciplinary literacy acquisition. The research contributes to the body of knowledge on educational technology by exemplifying how the DST teaching intervention could bridge the gap between EFL and non-EFL students’ disciplinary literacy acquisition in STEM areas

    Engaging adolescent Kyrgyzstani EFL students in digital storytelling projects about astronomy

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    This research is based on the Journey through Space and Time (JTST) educational astronomy project for primary and junior high school science curricula in Australia, which seeks to improve students\u27 astronomy content knowledge through science inquiry. The focus of the current project is on the learning needs of students for whom the language of instruction is a foreign or second language (EFL/ESL). This article reports the results of a pilot case study conducted in Bishkek, Kyrgyzstan in December 2017. The research employed a Type II Case Study design. Data were collected through video and audio recordings of classroom interactions. The Astronomy Diagnostic Test measured changes in content knowledge and written feedback at the end of the course and helped to understand students\u27 overall impression from the course. The study revealed that engaging Kyrgyzstani EFL students aged between 12 and 15 years in making videos about their learning of astronomy significantly facilitated their content knowledge acquisition. This research contributes to the existing knowledge about the use of technology in students\u27 science education, and specifically as a tool to enhance EFL students\u27 understanding of the integrated science, technology engineering and mathematics (STEM) curriculum. The results of the shared knowledge construction stimulated by the collaboration in video production create a case for further research in EFL students\u27 disciplinary literacy development

    Photo-antagonism of the GABAA receptor

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    Neurotransmitter receptor trafficking is fundamentally important for synaptic transmission and neural network activity. GABAA receptors and inhibitory synapses are vital components of brain function, yet much of our knowledge regarding receptor mobility and function at inhibitory synapses is derived indirectly from using recombinant receptors, antibody-tagged native receptors and pharmacological treatments. Here we describe the use of a set of research tools that can irreversibly bind to and affect the function of recombinant and neuronal GABAA receptors following ultraviolet photoactivation. These compounds are based on the competitive antagonist gabazine and incorporate a variety of photoactive groups. By using site-directed mutagenesis and ligand-docking studies, they reveal new areas of the GABA binding site at the interface between receptor β and α subunits. These compounds enable the selected inactivation of native GABAA receptor populations providing new insight into the function of inhibitory synapses and extrasynaptic receptors in controlling neuronal excitation

    Trans−cis Switching Mechanisms in Proline Analogues and Their Relevance for the Gating of the 5-HT3 Receptor

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    Trans-cis isomerization of a proline peptide bond is a potential mechanism to open the channel of the 5-HT3 receptor. Here, we have used the metadynamics method to theoretically explore such a mechanism. We have determined the free energy surfaces in aqueous solution of a series of dipeptides of proline analogues and evaluated the free energy difference between the cis and trans isomers. These theoretical results were then compared with data from mutagenesis experiments, in which the response of the 5-HT3 receptor was measured when the proline at the apex of the M2-M3 transmembrane domain loop was mutated. The strong correlation between the experimental and the theoretical data supports the existence of a trans-cis proline switch for opening the 5-HT3 receptor ion channel

    Resilience of marine ecosystems to climatic disturbances

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    The intensity and frequency of climate-driven disturbances are increasing in coastal marine ecosystems. Understanding the factors that enhance or inhibit ecosystem resilience to climatic disturbance is essential. We surveyed 97 experts in six major coastal biogenic ecosystem types to identify “bright spots” of resilience in the face of climate change. We also evaluated literature that was recommended by the experts that addresses the responses of habitat-forming species to climatic disturbance. Resilience was commonly reported in the expert surveys (80% of experts). Resilience was observed in all ecosystem types and at multiple locations worldwide. The experts and literature cited remaining biogenic habitat, recruitment/connectivity, physical setting, and management of local-scale stressors as most important for resilience. These findings suggest that coastal ecosystems may still hold great potential to persist in the face of climate change and that local- to regional-scale management can help buffer global climatic impacts

    Anaesthetic Impairment of Immune Function Is Mediated via GABAA Receptors

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    GABA(A) receptors are members of the Cys-loop family of neurotransmitter receptors, proteins which are responsible for fast synaptic transmission, and are the site of action of wide range of drugs. Recent work has shown that Cys-loop receptors are present on immune cells, but their physiological roles and the effects of drugs that modify their function in the innate immune system are currently unclear. We are interested in how and why anaesthetics increase infections in intensive care patients; a serious problem as more than 50% of patients with severe sepsis will die. As many anaesthetics act via GABA(A) receptors, the aim of this study was to determine if these receptors are present on immune cells, and could play a role in immunocompromising patients.We demonstrate, using RT-PCR, that monocytes express GABA(A) receptors constructed of α1, α4, β2, γ1 and/or δ subunits. Whole cell patch clamp electrophysiological studies show that GABA can activate these receptors, resulting in the opening of a chloride-selective channel; activation is inhibited by the GABA(A) receptor antagonists bicuculline and picrotoxin, but not enhanced by the positive modulator diazepam. The anaesthetic drugs propofol and thiopental, which can act via GABA(A) receptors, impaired monocyte function in classic immunological chemotaxis and phagocytosis assays, an effect reversed by bicuculline and picrotoxin.Our results show that functional GABA(A) receptors are present on monocytes with properties similar to CNS GABA(A) receptors. The functional data provide a possible explanation as to why chronic propofol and thiopental administration can increase the risk of infection in critically ill patients: their action on GABA(A) receptors inhibits normal monocyte behaviour. The data also suggest a potential solution: monocyte GABA(A) receptors are insensitive to diazepam, thus the use of benzodiazepines as an alternative anesthetising agent may be advantageous where infection is a life threatening problem

    Ligand Activation of the Prokaryotic Pentameric Ligand-Gated Ion Channel ELIC

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    While the pentameric ligand-gated ion channel ELIC has recently provided first insight into the architecture of the family at high resolution, its detailed investigation was so far prevented by the fact that activating ligands were unknown. Here we describe a study on the functional characterization of ELIC by electrophysiology and X-ray crystallography. ELIC is activated by a class of primary amines that include the neurotransmitter GABA at high micro- to millimolar concentrations. The ligands bind to a conserved site and evoke currents that slowly desensitize over time. The protein forms cation selective channels with properties that resemble the nicotinic acetylcholine receptor. The high single channel conductance and the comparably simple functional behavior make ELIC an attractive model system to study general mechanisms of ion conduction and gating in this important family of neurotransmitter receptors
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