141 research outputs found

    A taxonomy for Massive Open Online Courses

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    Teaching and Teacher Learning (ICLON

    MOOCs: Innovation or stagnation?

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    Issues of the phenomenon of Massive Open Online Course (MOOC) and its integration into current online and campus education to enhance higher education quality in universities is gaining importance. This large scale form of online education has the potential to escalate the reputations of universities and increase the global access to their institutions. However, the design and implementation of MOOCs is not easy. Thus, many higher education institutions take time for careful consideration before running them. Otherwise, this new online learning phenomenon, which is also called disruptive innovation, might cause some unintended negative economical and reputational results. This study aimed to examine the strengths and weaknesses as well as opportunities and threats of MOOCs in higher education. The data from the document analysis was examined by SWOT method to put insights on MOOCs internal and external standing. The electronic data including books, research reports, conference papers, journal articles, blog posts, discussion boards, and web forms were considered as a sample of the study. The findings show that accessibility, lifelong learning and brand extensions are some of the strengths of MOOCs, whereas dropout rates, poor pedagogy and low-quality assessments are major barriers for their effectiveness. Alternative education and collaborative learning are some of the outstanding opportunities MOOCs present, which worth the efforts to create more democratic and innovative higher education. Results indicated that it is worth to explore the ways to improve the completion rates, weak pedagogical structure, degree provision, quality insurance and assessment as well as to discover the needs of new generation in online learning.Teaching and Teacher Learning (ICLON

    Structural Integrity of Single Shell Tanks at Hanford -9491

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    ABSTRACT The 149 Single Shell Tanks at the Hanford Site were constructed between the 1940's and the 1960's. Many of the tanks are either known or suspected to have leaked in the past. While the free liquids have been removed from the tanks, they still contain significant waste volumes. Recently, the tank farm operations contractor established a Single Shell Tank Integrity Program. Structural integrity is one aspect of the program. The structural analysis of the Single Shell Tanks has several challenging factors. There are several tank sizes and configurations that need to be analyzed. Tank capacities range from fifty-five thousand gallons to one million gallons. The smallest tank type is approximately twenty feet in diameter, and the three other tank types are all seventy-five feet in diameter. Within each tank type there are varying concrete strengths, types of steel, tank floor arrangements, in-tank hardware, riser sizes and locations, and other appurtenances that need to be addressed. Furthermore, soil properties vary throughout the tank farms. The Pacific Northwest National Laboratory has been conducting preliminary structural analyses of the various single shell tank types to address these parameters. The preliminary analyses will assess which aspects of the tanks will require further detailed analysis. Evaluation criteria to which the tanks will be analyzed are also being developed for the Single Shell Tank Integrity Program. This information will be reviewed by the Single Shell Tank Integrity Expert Panel that has been formed to issue recommendations to the DOE and to the tank farm operations contractor regarding Single Shell Tank Integrity. This paper provides a summary of the preliminary analysis of the single shell tanks, a summary of the recommendations for the detailed analyses, and the proposed evaluation criteria by which the tanks will be judged

    Multifocal electroretinogram and Optical Coherence tomography spectral-domain in arc welding macular injury: a case report

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    <p>Abstract</p> <p>Background</p> <p>the purpose of this study was to report a binocular photic retinal injury induced by plasma arc welding and the follow-up after treatment with vitamin supplements for a month. In our study, we used different diagnostic tools such as fluorescein angiography (FA), optical coherence tomography (OCT) and multifocal electroretinogram (mfERG).</p> <p>Case presentation</p> <p>in the first visit after five days from arc welding injury in the left eye (LE) the visual acuity was 0.9 and 1.0 in the right eye (RE). FA was normal in both eyes. OCT in the left eye showed normal profile and normal reflectivity and one month later, a hyperreflectivity appeared in the external limiting membrane (ELM). The mfERG signal in the LE was 102.30 nV/deg2 five days after the injury and 112.62 nV/deg2 after one month and in the RE respectively 142.70 nV/deg2 and 159.46 nV/deg2.</p> <p>Conclusions</p> <p>in cases of retinal photo injury it is important for the ophthalmologist to evaluate tests such as OCT and the mfERG in the diagnosis and follow-up of the patient because the recovery of visual acuity cannot exclude the persistence of phototoxic damage charged to the complex inner-outer segment of photoreceptors.</p

    SARS-CoV-2 neutralizing antibodies: Longevity, breadth, and evasion by emerging viral variants.

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    The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) antibody neutralization response and its evasion by emerging viral variants and variant of concern (VOC) are unknown, but critical to understand reinfection risk and breakthrough infection following vaccination. Antibody immunoreactivity against SARS-CoV-2 antigens and Spike variants, inhibition of Spike-driven virus-cell fusion, and infectious SARS-CoV-2 neutralization were characterized in 807 serial samples from 233 reverse transcription polymerase chain reaction (RT-PCR)-confirmed Coronavirus Disease 2019 (COVID-19) individuals with detailed demographics and followed up to 7 months. A broad and sustained polyantigenic immunoreactivity against SARS-CoV-2 Spike, Membrane, and Nucleocapsid proteins, along with high viral neutralization, was associated with COVID-19 severity. A subgroup of "high responders" maintained high neutralizing responses over time, representing ideal convalescent plasma donors. Antibodies generated against SARS-CoV-2 during the first COVID-19 wave had reduced immunoreactivity and neutralization potency to emerging Spike variants and VOC. Accurate monitoring of SARS-CoV-2 antibody responses would be essential for selection of optimal responders and vaccine monitoring and design

    SARS-CoV-2 neutralizing antibodies : longevity, breadth, and evasion by emerging viral variants

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    The Severe Acute Respiratory Syndrome Coronavirus 2 (SAU ARS-CoV-2) antibody neutralization response and its evasion by emerging viral variants and variant of concern (VOC) are unknown, but critical to understand reinfection risk and breakthrough infection following vaccination. Antibody immunoreactivity against SARS-CoV-2 antigens and Spike variants, inhibition of Spike-driven virus–cell fusion, and infectious SARS-CoV-2 neutralization were characterized in 807 serial samples from 233 reverse transcription polymerase chain reaction (RT-PCR)–confirmed Coronavirus Disease 2019 (COVID-19) individuals with detailed demographics and followed up to 7 months. A broad and sustained polyantigenic immunoreactivity against SARS-CoV-2 Spike, Membrane, and Nucleocapsid proteins, along with high viral neutralization, was associated with COVID-19 severity. A subgroup of “high responders” maintained high neutralizing responses over time, representing ideal convalescent plasma donors. Antibodies generated against SARS-CoV-2 during the first COVID-19 wave had reduced immunoreactivity and neutralization potency to emerging Spike variants and VOC. Accurate monitoring of SARS-CoV-2 antibody responses would be essential for selection of optimal responders and vaccine monitoring and design

    Revising mtDNA haplotypes of the ancient Hungarian conquerors with next generation sequencing

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    As part of the effort to create a high resolution representative sequence database of the medieval Hungarian conquerors we have resequenced the entire mtDNA genome of 24 published ancient samples with Next Generation Sequencing, whose haplotypes had been previously determined with traditional PCR based methods. We show that PCR based methods are prone to erroneous haplotype or haplogroup determination due to ambiguous sequence reads, and many of the resequenced samples had been classified inaccurately. The SNaPshot method applied with published ancient DNA authenticity criteria is the most straightforward and cheapest PCR based approach for testing a large number of coding region SNP-s, which greatly facilitates correct haplogroup determination

    TBK1: a new player in ALS linking autophagy and neuroinflammation.

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    Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disorder affecting motor neurons, resulting in progressive muscle weakness and death by respiratory failure. Protein and RNA aggregates are a hallmark of ALS pathology and are thought to contribute to ALS by impairing axonal transport. Mutations in several genes known to contribute to ALS result in deposition of their protein products as aggregates; these include TARDBP, C9ORF72, and SOD1. In motor neurons, this can disrupt transport of mitochondria to areas of metabolic need, resulting in damage to cells and can elicit a neuroinflammatory response leading to further neuronal damage. Recently, eight independent human genetics studies have uncovered a link between TANK-binding kinase 1 (TBK1) mutations and ALS. TBK1 belongs to the IKK-kinase family of kinases that are involved in innate immunity signaling pathways; specifically, TBK1 is an inducer of type-1 interferons. TBK1 also has a major role in autophagy and mitophagy, chiefly the phosphorylation of autophagy adaptors. Several other ALS genes are also involved in autophagy, including p62 and OPTN. TBK1 is required for efficient cargo recruitment in autophagy; mutations in TBK1 may result in impaired autophagy and contribute to the accumulation of protein aggregates and ALS pathology. In this review, we focus on the role of TBK1 in autophagy and the contributions of this process to the pathophysiology of ALS
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