416 research outputs found

    Assessment, technology and democratic education in the age of data

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    This paper contends that powerful techniques to manipulate data, enabled by technological and economic developments, can be easily co-opted to serve the restrictive frameworks of hyper-controlling, managerial accountability that characterise current cultures of summative assessment in education. In response to these challenges, research is urgently needed to increase our understanding of the impact that assessments have on individuals and society. The paper concludes that social research ought to contribute to the identification of responses – educational, technological and political – that can minimise inequalities and potential abuses through the encouragement of data literacy across society

    Crowdsourcing malaria parasite quantification: an online game for analyzing images of infected thick blood smears

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    Background: There are 600,000 new malaria cases daily worldwide. The gold standard for estimating the parasite burden and the corresponding severity of the disease consists in manually counting the number of parasites in blood smears through a microscope, a process that can take more than 20 minutes of an expert microscopist’s time. Objective: This research tests the feasibility of a crowdsourced approach to malaria image analysis. In particular, we investigated whether anonymous volunteers with no prior experience would be able to count malaria parasites in digitized images of thick blood smears by playing a Web-based game. Methods: The experimental system consisted of a Web-based game where online volunteers were tasked with detecting parasites in digitized blood sample images coupled with a decision algorithm that combined the analyses from several players to produce an improved collective detection outcome. Data were collected through the MalariaSpot website. Random images of thick blood films containing Plasmodium falciparum at medium to low parasitemias, acquired by conventional optical microscopy, were presented to players. In the game, players had to find and tag as many parasites as possible in 1 minute. In the event that players found all the parasites present in the image, they were presented with a new image. In order to combine the choices of different players into a single crowd decision, we implemented an image processing pipeline and a quorum algorithm that judged a parasite tagged when a group of players agreed on its position. Results: Over 1 month, anonymous players from 95 countries played more than 12,000 games and generated a database of more than 270,000 clicks on the test images. Results revealed that combining 22 games from nonexpert players achieved a parasite counting accuracy higher than 99%. This performance could be obtained also by combining 13 games from players trained for 1 minute. Exhaustive computations measured the parasite counting accuracy for all players as a function of the number of games considered and the experience of the players. In addition, we propose a mathematical equation that accurately models the collective parasite counting performance. Conclusions: This research validates the online gaming approach for crowdsourced counting of malaria parasites in images of thick blood films. The findings support the conclusion that nonexperts are able to rapidly learn how to identify the typical features of malaria parasites in digitized thick blood samples and that combining the analyses of several users provides similar parasite counting accuracy rates as those of expert microscopists. This experiment illustrates the potential of the crowdsourced gaming approach for performing routine malaria parasite quantification, and more generally for solving biomedical image analysis problems, with future potential for telediagnosis related to global health challenges

    Cessation of mass drug administration for lymphatic filariasis in Zanzibar in 2006: was transmission interrupted?

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    BACKGROUND: Lymphatic filariasis (LF) is targeted for elimination through annual mass drug administration (MDA) for 4-6 years. In 2006, Zanzibar stopped MDA against LF after five rounds of MDA revealed no microfilaraemic individuals during surveys at selected sentinel sites. We asked the question if LF transmission was truly interrupted in 2006 when MDA was stopped. METHODOLOGY/PRINCIPAL FINDINGS: In line with ongoing efforts to shrink the LF map, we performed the WHO recommended transmission assessment surveys (TAS) in January 2012 to verify the absence of LF transmission on the main Zanzibar islands of Unguja and Pemba. Altogether, 3275 children were tested on both islands and 89 were found to be CFA positive; 70 in Pemba and 19 in Unguja. The distribution of schools with positive children was heterogeneous with pronounced spatial variation on both islands. Based on the calculated TAS cut-offs of 18 and 20 CFA positive children for Pemba and Unguja respectively, we demonstrated that transmission was still ongoing in Pemba where the cut-off was exceeded. CONCLUSIONS: Our findings indicated ongoing transmission of LF on Pemba in 2012. Moreover, we presented evidence from previous studies that LF transmission was also active on Unguja shortly after stopping MDA in 2006. Based on these observations the government of Zanzibar decided to resume MDA against LF on both islands in 2013

    Deep Hole States in Medium Mass Nuclei

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    Supported by the National Science Foundation and Indiana Universit

    Limitations of Student Control: Do Students Know when They Need Help?

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    The changing role of pre-admission work experience (clinical visits) in Therapeutic Radiography, Diagnostic Radiography and Operating Department Practice: Student perspectives (Part 1)

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    Introduction Clinical visits (work experience opportunities) are a recommended part of admissions processes for many diagnostic and therapeutic radiography courses but not for operating department practice (ODP) where observational visits are challenging for applicants to obtain. The Covid-19 pandemic interrupted access to visits for all prospective students; this study presents a review of the value of clinical visits and alternatives. Methods This article reports the initial qualitative phase of a three-phase mixed methods study. Using a critical realist approach, focus groups explored first year student experiences of the ‘ideal’ pre-admission clinical visit and alternative resources. A structured review of Online Prospectus (OLP) entries was undertaken by two student researchers to ascertain the requirements for clinical visits for the three professions. Results Four focus groups included 25 first year students interviewed prior to their first clinical placement (14 therapeutic radiography, 5 diagnostic radiography and 6 ODP students). Three themes were constructed, namely: informing career choices, the clinical visit experience, and the value of clinical visits. Clinical visits affirmed rather than inspired career choices. The best timing for a visit was before admission interviews and optimal duration was a full day. Interacting with current students was the most valued aspect. Videos and simulations provided in-depth information about the professional role and allowed replay, but some participants found the videos uninspiring. OLP entries present a confusing picture for applicants who may be researching several Universities and professions. Conclusion Clinical visits were deemed ‘vital’ to radiography student career choices, yet ODPs who could not access visits were comfortable with videos. Simulated visits are a safe option amidst the pandemic but must capture the dynamic and patient-centred nature of practice to accurately inform career choices

    Effects of acute hypoglycemia on working memory and language processing in adults with and without type 1 diabetes

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    OBJECTIVE To examine the effects of hypoglycemia on language processing in adults with and without type 1 diabetes. RESEARCH DESIGN AND METHODS Forty adults were studied (20 with type 1 diabetes and 20 healthy volunteers) using a hyperinsulinemic glucose clamp to lower blood glucose to 2.5 mmol/L (45 mg/dL) (for 60 min, or to maintain blood glucose at 4.5 mmol/L (81 mg/dL) (euglycemia), on separate occasions. Language tests were applied to assess the effects of hypoglycemia on the relationship between working memory and language (reading span), grammatical decoding (self-paced reading), and grammatical encoding (subject-verb agreement). RESULTS Hypoglycemia caused a significant deterioration in reading span (P < 0.001; eta(2) = 0.37; Cohen d = 0.65) and a fall in correct responses (P = 0.005; eta(2) = 0.19; Cohen d = 0.41). On the self-paced reading test, the reading time for the first sentence fragment increased during hypoglycemia (P = 0.039; eta(2) = 0.11; Cohen d = 0.25). For the reading of the next fragment, hypoglycemia affected the healthy volunteer groupmore than the adults with type 1 diabetes (P = 0.03; eta(2) = 0.12; Cohen d = 0.25). However, hypoglycemia did not significantly affect the number of errors in sentence comprehension or the time taken to answer questions. Hypoglycemia caused a deterioration of subject-verb agreement (correct responses: P = 0.011; eta(2) = 0.159; Cohen d = 0.31). CONCLUSIONS Hypoglycemia caused a significant deterioration in reading span and in the accuracy of subject-verb agreement, both of which are practical aspects of language involved in its everyday use. Language processing is therefore impaired during moderate hypoglycemia

    Permanent magnet array for the magnetic refrigerator

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    Recent research into the development of magnetic refrigeration (MR) operating at room temperature has shown that it can provide a reliable, energy-efficient cooling system. To enhance the cooling power of the magnetic refrigerator, it is required to use a magnetic refrigerant material with large magnetocaloric effect (MCE) at the appropriate temperature. Most advanced magnetic refrigerant materials show largest MCE at high applied magnetic fields generated by a superconducting magnet. For application of MCE to air conditioners or household refrigerators, it is essential to develop a permanent magnet array to form a compact, strong, and energy-efficient magnetic field generator. Generating a magnetic field well above the remanence of a permanent magnetmaterial is hard to achieve through conventional designs. A permanent magnet array based on a hollow cylindrical flux source is found to provide an appropriate geometry and magnetic field strength for MR applications.The following article is from Journal of Applied Physics 91 (2002): 8894 and may be found at http://dx.doi.org/10.1063/1.1451906.</p
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