5,640 research outputs found

    6-Uniform Maker-Breaker Game Is PSPACE-Complete

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    In a STOC 1976 paper, Schaefer proved that it is PSPACE-complete to determine the winner of the so-called Maker-Breaker game on a given set system, even when every set has size at most 11. Since then, there has been no improvement on this result. We prove that the game remains PSPACE-complete even when every set has size 6

    Complexity of Unordered CNF Games

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    The classic TQBF problem is to determine who has a winning strategy in a game played on a given CNF formula, where the two players alternate turns picking truth values for the variables in a given order, and the winner is determined by whether the CNF gets satisfied. We study variants of this game in which the variables may be played in any order, and each turn consists of picking a remaining variable and a truth value for it. - For the version where the set of variables is partitioned into two halves and each player may only pick variables from his/her half, we prove that the problem is PSPACE-complete for 5-CNFs and in P for 2-CNFs. Previously, it was known to be PSPACE-complete for unbounded-width CNFs (Schaefer, STOC 1976). - For the general unordered version (where each variable can be picked by either player), we also prove that the problem is PSPACE-complete for 5-CNFs and in P for 2-CNFs. Previously, it was known to be PSPACE-complete for 6-CNFs (Ahlroth and Orponen, MFCS 2012) and PSPACE-complete for positive 11-CNFs (Schaefer, STOC 1976)

    How Do Surgeon Preferences and Technique Variances Affect Outcome?

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    The goal of the research project is to create a blue-print of a robot-assisted hysterectomy procedure to support design and evaluation of technology to enhance system performance. To create this blue-print, we will conduct a task analysis, model the cognitive task flow and decision making, and develop a simulation of the hysterectomy procedure. The surgical simulation will be used as a platform to train surgeons on robotic-assisted hysterectomies, as well as to assess learning and performance. Additionally, it will be used to design and develop techniques and novel technology to support surgeons in their performance of the surgery. Current research efforts are focused on the task analysis step. Data collection included observations in the hospital operating room, interviews with surgeons and nurses, analysis of surgery instructional videos and textbooks. A hierarchical task decomposition has been conducted. Thus far, results of the task analysis reveal several different types of hysterectomies and large variance in surgical techniques based on each surgeon’s preference. These findings will be validated by expert surgeons, and supplemented with a cognitive task analysis. In the next phase of the research project, we will identify several critical decision points within the surgical procedure that include variations in the use of surgical tools or variations in the sequence of actions. For example, the use of a uterine manipulator during the hysterectomy procedure seems to have an impact on the surgeon’s ease, speed, and accuracy while performing the procedure. These variations will be modeled and incorporated into the surgical simulation during development. Ultimately, the simulator will be used to train and assess the physician’s performance. It will also allow us to analyze the difference in techniques and how that affects patient outcome. A surgical simulation that has been designed and developed based on a systematic task analysis and cognitive model will allow us to more accurately study the requirements and constraints of the surgical environment, and support future innovate to enhance surgical performance and patient safety.https://corescholar.libraries.wright.edu/urop_celebration/1142/thumbnail.jp

    User Testing to Improve Retrieval and Comprehension of Information in Guidelines to Improve Medicines Safety

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    Objective: The aim of the study was to investigate the effectiveness of user testing for improving healthcare professionals’ retrieval and comprehension of information in medicines guidelines. Methods: The United Kingdom’s Injectable Medicines Guide was selected as a case study. This gives guidance to nurses on preparing and administering intravenous medicines on hospital wards, in line with standard UK practice. Three rounds of user testing were completed with 10 hospital nurses per round, using the Injectable Medicines Guide for voriconazole and aminophylline. Participants used the guidelines to answer 17 questions related to the administration of these medicines. Answers were scored for “finding” and “understanding” the required information. Semistructured interviews explored participants’ opinions of guideline content, design, and wording, with responses analyzed thematically. The guidelines were revised between rounds. Results: In round 1, 8 of 17 questions were answered correctly by all participants. Participants had difficulty with dose, dilution, administration rate, and adverse effects questions. Revisions included new subsections and increased calculation support. In round 2, 14 of 17 questions were answered correctly by all participants. Difficulty persisted with dose and administration rate questions and further revisions made. In round 3, 15 of 17 questions were answered correctly by all participants. Across all rounds, participants considered appropriate subheadings and information order as important for fast location of information. Specific, detailed, and practical instructions were perceived as important to improve understandability and usefulness. Conclusions: Key information in medicines guidelines may not be found and/or understood by healthcare professionals. User testing increased information retrieval and comprehension and could have an important role in improving the safety of medicines use

    User-testing guidelines to improve the safety of intravenous medicines administration: a randomised in situ simulation study

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    Background: User-testing and subsequent modification of clinical guidelines increases health professionals’ information retrieval and comprehension. No study has investigated whether this results in safer care. Objective: To compare the frequency of medication errors when administering an intravenous medicine using the current National Health Service Injectable Medicines Guide (IMG) versus an IMG version revised with user-testing. Method: Single-blind, randomised parallel group in situ simulation. Participants were on-duty nurses/midwives who regularly prepared intravenous medicines. Using a training manikin in their clinical area, participants administered a voriconazole infusion, a high-risk medicine requiring several steps to prepare. They were randomised to use current IMG guidelines or IMG guidelines revised with user-testing. Direct observation was used to time the simulation and identify errors. Participant confidence was measured using a validated instrument. The primary outcome was the percentage of simulations with at least one moderate-severe IMG-related error, with error severity classified by an expert panel. Results: In total, 133 participants were randomised to current guidelines and 140 to user-tested guidelines. Fewer moderate-severe IMG-related errors occurred with the user-tested guidelines (n=68, 49%) compared with current guidelines (n=79, 59%), but this difference was not statistically significant (risk ratio: 0.82; 95% CI 0.66 to 1.02). Significantly more simulations were completed without any IMG-related errors with the user-tested guidelines (n=67, 48%) compared with current guidelines (n=26, 20%) (risk ratio: 2.46; 95% CI 1.68 to 3.60). Median simulation completion time was 1.6 min (95% CI 0.2 to 3.0) less with the user-tested guidelines. Participants who used user-tested guidelines reported greater confidence. Conclusion: User-testing injectable medicines guidelines reduces the number of errors and the time taken to prepare and administer intravenous medicines, while increasing staff confidence. Trial registration number: researchregistry5275

    Development of a single nucleotide polymorphism (SNP) marker for detection of the low phytic acid (lpa1-1) gene used during maize breeding

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    Breeding for low phytic acid (LPA) in maize is hampered by a tedious and destructive colorimetric assay in mature dry grain. There are no molecular markers available for the single recessive gene of lpa1-1, restricting breeding programmes. The aim of this study is to develop a molecular marker to identify the lpa1-1 gene at the early vegetative plant stage. The parental lines are temperate LPA line (CM 32) and tropical line (P 16). The lpa1-1 allele is due to a single amino acid change from alanine to valine. The nature of the single nucleotide polymorphism (SNP) marker was validated by DNA sequencing of the parental PCR products. Using high resolution melt (HRM) profiles and normalised difference plots, we successfully differentiated the homozygous dominant (wild type), homozygous recessive (LPA) and heterozygous genotypes. The reduced phytate content of the LPA parental line was confirmed. The profiles from low cost crude and high quality DNA extraction were comparable when distinguishing between the parental lines. The cost of HRM analysis was 8% of the cost of PCR amplification and DNA sequencing. The development of the marker will make maize breeding for LPA efficient and fast, and it will enable the earlier release of lpa1-1 varieties.Keywords: High resolution melt (HRM) analysis, low phytic acid, maize, single nucleotide polymorphism (SNP) markerAfrican Journal of Biotechnology Vol. 12(9), pp. 892-90

    User-testing guidelines to improve the safety of intravenous medicines administration: a randomised in situ simulation study

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    Background: User-testing and subsequent modification of clinical guidelines increases health professionals’ information retrieval and comprehension. No study has investigated whether this results in safer care. Objective: To compare the frequency of medication errors when administering an intravenous medicine using the current National Health Service Injectable Medicines Guide (IMG) versus an IMG version revised with user-testing. Method: Single-blind, randomised parallel group in situ simulation. Participants were on-duty nurses/midwives who regularly prepared intravenous medicines. Using a training manikin in their clinical area, participants administered a voriconazole infusion, a high-risk medicine requiring several steps to prepare. They were randomised to use current IMG guidelines or IMG guidelines revised with user-testing. Direct observation was used to time the simulation and identify errors. Participant confidence was measured using a validated instrument. The primary outcome was the percentage of simulations with at least one moderatesevere IMG-related error, with error severity classified by an expert panel. Results: In total, 133 participants were randomised to current guidelines and 140 to user-tested guidelines. Fewer moderate-severe IMG-related errors occurred with the user-tested guidelines (n=68, 49%) compared with current guidelines (n=79, 59%), but this difference was not statistically significant (risk ratio: 0.82; 95% CI 0.66 to 1.02). Significantly more simulations were completed without any IMG-related errors with the usertested guidelines (n=67, 48%) compared with current guidelines (n=26, 20%) (risk ratio: 2.46; 95% CI 1.68 to 3.60). Median simulation completion time was 1.6min (95% CI 0.2 to 3.0) less with the user-tested guidelines. Participants who used user-tested guidelines reported greater confidence. Conclusion: User-testing injectable medicines guidelines reduces the number of errors and the time taken to prepare and administer intravenous medicines, while increasing staff confidence. Trial registration: number researchregistry5275
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