4,540 research outputs found

    Brief Announcement: A Tight Lower Bound for Clock Synchronization in Odd-Ary M-Toroids

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    In this paper we show a tight closed-form expression for the optimal clock synchronization in k-ary m-cubes with wraparound, where k is odd. This is done by proving a lower bound of 1/4um (k-1/k), where k is the (odd) number of processes in each of the m dimensions, and u is the uncertainty in delay on every link. Our lower bound matches the previously known upper bound

    Protein Secondary Structure Prediction using Parallelized Rule Induction from Coverings

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    Protein 3D structure prediction has always been an important research area in bioinformatics. In particular, the prediction of secondary structure has been a well-studied research topic. Despite the recent breakthrough of combining multiple sequence alignment information and artificial intelligence algorithms to predict protein secondary structure, the Q3 accuracy of various computational prediction algorithms rarely has exceeded 75%. In a previous paper [1], this research team presented a rule-based method called RT-RICO (Relaxed Threshold Rule Induction from Coverings) to predict protein secondary structure. The average Q3 accuracy on the sample datasets using RT-RICO was 80.3%, an improvement over comparable computational methods. Although this demonstrated that RT-RICO might be a promising approach for predicting secondary structure, the algorithm\u27s computational complexity and program running time limited its use. Herein a parallelized implementation of a slightly modified RT-RICO approach is presented. This new version of the algorithm facilitated the testing of a much larger dataset of 396 protein domains [2]. Parallelized RTRICO achieved a Q3 score of 74.6%, which is higher than the consensus prediction accuracy of 72.9% that was achieved for the same test dataset by a combination of four secondary structure prediction methods [2]

    Using Peer Discussion Facilitated by Clicker Questions in an Informal Education Setting : Enhancing Farmer Learning of Science

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    PLoS ONE, Vol. 7, No. 10Blueberry growers in Maine attend annual Cooperative Extension presentations given by university faculty members. These presentations cover topics, such as, how to prevent plant disease and monitor for insect pests. In 2012, in order to make the sessions more interactive and promote learning, clicker questions and peer discussion were incorporated into the presentations. Similar to what has been shown at the undergraduate level, after peer discussion, more blueberry growers gave correct answers to multiple-choice questions than when answering independently. Furthermore, because blueberry growers are characterized by diverse levels of education, experience in the field etc., we were able to determine whether demographic factors were associated with changes in performance after peer discussion. Taken together, our results suggest that clicker questions and peer discussion work equally well with adults from a variety of demographic backgrounds without disadvantaging a subset of the population and provide an important learning opportunity to the least formally educated members. Our results also indicate that clicker questions with peer discussion were viewed as a positive addition to university-related informal science education sessions

    Three-Year Longitudinal Service-Learning Research Study: Preliminary Findings

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    Using an experimental design, this study examines the contributions of service-learning to decreased at-risk behaviors, student cognitive, social, and personal development, and academic achievement over a three-year period. During the pilot phase and Years One and Two, teachers and students from eleven different Ohio schools have been surveyed. Preliminary findings are presented

    Identifying Senescence as a Mode of Chemo Resistance in Ovarian Cancer

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    Current treatments of ovarian and breast cancer result in chemo resistance all too often. It has been hypothesized that senescence-a dormant condition associated with increased age and apoptosis- may play a role in the development of chemo resistance. We performed an in-vitro study with HOSE (carboplatin-sensitive), SKOV3 (chemo resistant ovarian cancer), and CAMA1 (chemo resistant breast cancer) cell lines, which were exposed to a variety of platinum-based treatments meant to model current cover clinically relevant scenarios in terms of tumor hypoxia. They were then stained for senescence in-vitro using B-gal, and analyzed for proliferation using the Cell Counting Kit 8, trypan blue dye exclusion, and survival plating, among other methods. Real-time quantitative PCR was used to determine relative levels of gene expression for classical apoptotic and senescent markers. Our results indicate that proliferation was temporarily halted in SKOV3 and CAMA1 after treatment. Cell proliferation later resumed in these cell lines while HOSE cell underwent apoptosis. Analysis of genetic tests (such as qPCR) also revealed that SKOV3 and CAMA1 had decreased gene expression of key genes that regulate apoptosis and senescence (such as p53 and CDK2). It can be concluded from this data that senescence was in fact a mode of chemoresistance and that future treatments may want to focus on disabling cancerous cells’ senescent stage

    Pilot In-Trail Procedure Validation Simulation Study

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    A Human-In-The-Loop experiment was conducted at the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) to investigate the viability of the In-Trail Procedure (ITP) concept from a flight crew perspective, by placing participating airline pilots in a simulated oceanic flight environment. The test subject pilots used new onboard avionics equipment that provided improved information about nearby traffic and enabled them, when specific criteria were met, to request an ITP flight level change referencing one or two nearby aircraft that might otherwise block the flight level change. The subject pilots subjective assessments of ITP validity and acceptability were measured via questionnaires and discussions, and their objective performance in appropriately selecting, requesting, and performing ITP flight level changes was evaluated for each simulated flight scenario. Objective performance and subjective workload assessment data from the experiment s test conditions were analyzed for statistical and operational significance and are reported in the paper. Based on these results, suggestions are made to further improve the ITP

    Operational Improvements From the In-Trail Procedure in the North Atlantic Organized Track System

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    This paper explains the computerized batch processing experiment examining the operational impacts of the introduction of Automatic Dependent Surveillance-Broadcast (ADS-B) equipment and the In-Trail Procedure (ITP) to the North Atlantic Organized Track System (NATOTS). This experiment was conducted using the Traffic Manager (TMX), a desktop simulation capable of simulating airspace environments and aircraft operations. ADS-B equipment can enable the use of new ground and airborne procedures, such as the ITP. The ITP is among the first of these new procedures, which will make use of improved situation awareness in the local surrounding airspace of ADS-B equipped aircraft to enable more efficient oceanic flight level changes. The data collected were analyzed with respect to multiple operationally relevant parameters including fuel burn, request approval rates, and the distribution of fuel savings. This experiment showed that through the use of ADS-B or ADS-B and the ITP that operational improvements and benefits could be achieved
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