31 research outputs found

    Improving Mastery of Science Concepts Using Problem Based Learning Models in Class V in Elementary School

    Get PDF
    The background of this study is the low mastery of science concepts by fifth grade students at SDN 008 Salo Timur. This study aims to improve the mastery of science concepts using the problem-based learning model for class V in elementary schools. This research is a class follow-up research, which was carried out in two cycles and each cycle consisted of two meetings. The subjects in this study consisted of 1 teacher and 29 students, while the object was to use a problem-based learning model to improve students' mastery of science concepts. The research instrument consisted of teacher activity observation sheets and student activity observation sheets, test sheets and documentation sheets during the learning process using the problem based learning model. While the data analysis technique used is descriptive qualitative and quantitative analysis. Based on the results of research that has been carried out through 2 cycles, at the second meeting of cycle I mastery of classical mastery of science concepts students only 24.13% in the low category and the average learning value is only 67.03 in the medium category. It is known that there was an increase in students' mastery of science concepts after improvements were made in the second cycle of meeting 2, the classical mastery of students' science concepts was 86.20% in the very high category and the average student learning score was 80.55 in the high category. Based on the results of the study, it can be concluded that if the problem-based learning model is used , it can improve students' mastery of science concepts in class V 008 Salo Timur.   Keywords: Mastery of Science Concepts, problem based learning (PBL

    Central retinal vein occlusion revealing celiac disease

    Get PDF
    Introduction: Thrombosis has been widely reported in coeliac disease (CD) but central retinal vein occlusion (CRVO) is rarely described. Case presentation: A 27-year-old woman presented with acute visual loss and was diagnosed with CRVO. Her protein S and protein C levels were low and CD was diagnosed on the basis of endoscopic, immunological and histological results. A gluten-free diet resulted in favourable evolution. Conclusion: CD should be considered in young patients with thrombosis, especially if in an unusual location. Treatment is based on a gluten-free diet

    (Un)informed Consent: Studying GDPR Consent Notices in the Field

    Full text link
    Since the adoption of the General Data Protection Regulation (GDPR) in May 2018 more than 60 % of popular websites in Europe display cookie consent notices to their visitors. This has quickly led to users becoming fatigued with privacy notifications and contributed to the rise of both browser extensions that block these banners and demands for a solution that bundles consent across multiple websites or in the browser. In this work, we identify common properties of the graphical user interface of consent notices and conduct three experiments with more than 80,000 unique users on a German website to investigate the influence of notice position, type of choice, and content framing on consent. We find that users are more likely to interact with a notice shown in the lower (left) part of the screen. Given a binary choice, more users are willing to accept tracking compared to mechanisms that require them to allow cookie use for each category or company individually. We also show that the wide-spread practice of nudging has a large effect on the choices users make. Our experiments show that seemingly small implementation decisions can substantially impact whether and how people interact with consent notices. Our findings demonstrate the importance for regulation to not just require consent, but also provide clear requirements or guidance for how this consent has to be obtained in order to ensure that users can make free and informed choices.Comment: 18 pages, 6 figures, 2019 ACM SIGSAC Conference on Computer and Communications Security (CCS '19), November 11-15, 2019, London, United Kingdo

    Evaluating the End-User Experience of Private Browsing Mode

    Get PDF
    Nowadays, all major web browsers have a private browsing mode. However, the mode's benefits and limitations are not particularly understood. Through the use of survey studies, prior work has found that most users are either unaware of private browsing or do not use it. Further, those who do use private browsing generally have misconceptions about what protection it provides. However, prior work has not investigated \emph{why} users misunderstand the benefits and limitations of private browsing. In this work, we do so by designing and conducting a three-part study: (1) an analytical approach combining cognitive walkthrough and heuristic evaluation to inspect the user interface of private mode in different browsers; (2) a qualitative, interview-based study to explore users' mental models of private browsing and its security goals; (3) a participatory design study to investigate why existing browser disclosures, the in-browser explanations of private browsing mode, do not communicate the security goals of private browsing to users. Participants critiqued the browser disclosures of three web browsers: Brave, Firefox, and Google Chrome, and then designed new ones. We find that the user interface of private mode in different web browsers violates several well-established design guidelines and heuristics. Further, most participants had incorrect mental models of private browsing, influencing their understanding and usage of private mode. Additionally, we find that existing browser disclosures are not only vague, but also misleading. None of the three studied browser disclosures communicates or explains the primary security goal of private browsing. Drawing from the results of our user study, we extract a set of design recommendations that we encourage browser designers to validate, in order to design more effective and informative browser disclosures related to private mode

    Empirical Research Methods in Usable Privacy and Security

    Get PDF
    Researchers in the usable privacy and security (UPS) field study privacy- and security-relevant perceptions and behaviors and aim to design systems that simul- taneously address requirements for usability/user experience, security, and privacy. Human-computer interaction (HCI) and social science research methods are well-suited to study many of the types of questions that are relevant in UPS, which often involve concepts such as subjective experience, attitudes, understanding, behavior and behavior change. However, there are many challenges specific to UPS that are not usually described in more generic methods textbooks. We highlight techniques for risk representation, options for participant recruitment, ethics-related topics in study design, and biases that may play a role in UPS studies with human participants

    Novel Slippery Liquid-Infused Porous Surfaces (SLIPS) based on electrospun polydimethylsiloxane/polystyrene fibrous structures infused with natural blackseed oil

    Get PDF
    Hydrophobic fibrous slippery liquid-infused porous surfaces (SLIPS) were fabricated by electrospinning polydimethylsiloxane (PDMS) and polystyrene (PS) as a carrier polymer on plasma-treated polyethylene (PE) and polyurethane (PU) substrates. Subsequent infusion of blackseed oil (BSO) into the porous structures was applied for the preparation of the SLIPS. SLIPS with infused lubricants can act as a repellency layer and play an important role in the prevention of biofilm formation. The effect of polymer solutions used in the electrospinning process was investigated to obtain well-defined hydrophobic fibrous structures. The surface properties were analyzed through various optical, macroscopic and spectroscopic techniques. A comprehensive investigation of the surface chemistry, surface morphology/topography, and mechanical properties was carried out on selected samples at optimized conditions. The electrospun fibers prepared using a mixture of PDMS/PS in the ratio of 1:1:10 (g/g/mL) using tetrahydrofuran (THF) solvent showed the best results in terms of fiber uniformity. The subsequent infusion of BSO into the fabricated PDMS/PS fiber mats exhibited slippery behavior regarding water droplets. Moreover, prepared SLIPS exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli bacterium strains.RP/CPS/2022/001, RP/CPS/2022/002; Qatar National Research Fund, QNRFQatar National Research Fund (a member of The Qatar Foundation) [NPRP13S-0123-200153, JSREP 07-022-3-010]; Ministry of Education, Youth and Sports of the Czech Republic DKRVO [RP/CPS/2022/001, RP/CPS/2022/002

    Mapping national information and communication technology (ICT) infrastructure to the requirements of potential digital health interventions in low- and middle-income countries

    Get PDF
    Background Digital health can support health care in low- and middle-income countries (LMICs) by overcoming problems of distance, poor infrastructure and the need to provide community practitioners with specialist support. We used five RESPIRE countries as exemplars (Bangladesh, India, Indonesia, Malaysia, Pakistan) to identify the digital health solutions that are valuable in their local setting, worked together with local clinicians and researchers to explore digital health policy, electricity/ICT infrastructure, and socio-cultural factors influencing users’ ability to access, adopt and utilise digital health. Methods We adopted the Joanna Briggs Institute’s scoping review protocol and followed the Cochrane Rapid Review method to accelerate the review process, using the Implementation and Operation of Mobile Health projects framework and The Extended Technology Acceptance Model of Mobile Telephony to categorise the results. We conducted the review in four stages: (1) establishing value, (2) identifying digital health policy, (3) searching for evidence of infrastructure, design, and end-user adoption, (4) local input to interpret relevance and adoption factors. We used open-source national/international statistics such as the World Health Organization, International Telecommunication Union, Groupe Speciale Mobile, and local news/articles/government statistics to scope the current status, and systematically searched five databases for locally relevant exemplars. Results We found 118 studies (2015-2021) and 114 supplementary online news articles and national statistics. Digital health policy was available in all countries, but scarce skilled labour, lack of legislation/interoperability support, and interrupted electricity and internet services were limitations. Older patients, women and those living in rural areas were least likely to have access to ICT infrastructure. Renewable energy has potential in enabling digital health care. Low usage mobile data and voice service packages are relatively affordable options for mHealth in the five countries. Conclusions Effective implementation of digital health technologies requires a supportive policy, stable electricity infrastructures, affordable mobile internet service, and good understanding of the socio-economic context in order to tailor the intervention such that it functional, accessible, feasible, user-friendly and trusted by the target users. We suggest a checklist of contextual factors that developers of digital health initiatives in LMICs should consider at an early stage in the development process

    On a Clique-Based Integer Programming Formulation of Vertex Colouring with Applications in Course Timetabling

    Full text link
    Vertex colouring is a well-known problem in combinatorial optimisation, whose alternative integer programming formulations have recently attracted considerable attention. This paper briefly surveys seven known formulations of vertex colouring and introduces a formulation of vertex colouring using a suitable clique partition of the graph. This formulation is applicable in timetabling applications, where such a clique partition of the conflict graph is given implicitly. In contrast with some alternatives, the presented formulation can also be easily extended to accommodate complex performance indicators (``soft constraints'') imposed in a number of real-life course timetabling applications. Its performance depends on the quality of the clique partition, but encouraging empirical results for the Udine Course Timetabling problem are reported
    corecore