819 research outputs found

    6th–8th Grade: English Level 1, Learning Packet #2 • Theme: Migrations and Family [Students with Interrupted Formal Schooling]

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    Day 1 • Migration and geography vocabulary, What are verbs?, Numbers 1-10, Introduce someone else Day 2 • Family vocabulary, New vocabulary, Where are you from? Day 3 • Vocabulary review, What are pronouns?, Family relationships reading, Write about your family, My family compare and contrast, Compare and contrast Ahmed\u27s family, Compare and contrast your family Day 4 • , Ku Moo\u27s journey Day 5 • Where are you from? My Packet Journal Reference Sheet Answer Key

    Human-driven Machine-automation of Engineering Research

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    This paper presents a framework for efficiently producing engineering research in a global collaborative effort in a rigorous scientific manner. The proposed framework reduces subjective analysis, automates several mundane research tasks and provides a suitable formal structure for efficient information sharing and collaboration. The implementation of the framework involves multiple research groups setting up different web-servers that can perform the steps of the scientific method and automatically determine the quality and value of new research by directly communicating between servers via public and private Application Programming Interfaces (APIs) using a set of object-oriented protocols. The automation of many mundane research tasks (e.g. data manipulation), would allow researchers to focus more on the novel aspects of their research efforts. The increased clarity around the quality and value of research would allow the research efforts of individuals and available research funding to be better disbursed. The paper discusses the major aspects of the scientific method, object-orientated programming, the application of the proposed research framework for experimental/analytical/numerical engineering research, some of the potential benefits and drawbacks, as well as the current state of implementation

    Proof Theory, Transformations, and Logic Programming for Debugging Security Protocols

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    We define a sequent calculus to formally specify, simulate, debug and verify security protocols. In our sequents we distinguish between the current knowledge of principals and the current global state of the session. Hereby, we can describe the operational semantics of principals and of an intruder in a simple and modular way. Furthermore, using proof theoretic tools like the analysis of permutability of rules, we are able to find efficient proof strategies that we prove complete for special classes of security protocols including Needham-Schroeder. Based on the results of this preliminary analysis, we have implemented a Prolog meta-interpreter which allows for rapid prototyping and for checking safety properties of security protocols, and we have applied it for finding error traces and proving correctness of practical examples

    Deduction with XOR Constraints in Security API Modelling

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    We introduce XOR constraints, and show how they enable a theorem prover to reason effectively about security critical subsystems which employ bitwise XOR. Our primary case study is the API of the IBM 4758 hardware security module. We also show how our technique can be applied to standard security protocols

    Effects of an Unusual Poison Identify a Lifespan Role for Topoisomerase 2 in Saccharomyces Cerevisiae

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    A progressive loss of genome maintenance has been implicated as both a cause and consequence of aging. Here we present evidence supporting the hypothesis that an age-associated decay in genome maintenance promotes aging in Saccharomyces cerevisiae (yeast) due to an inability to sense or repair DNA damage by topoisomerase 2 (yTop2). We describe the characterization of LS1, identified in a high throughput screen for small molecules that shorten the replicative lifespan of yeast. LS1 accelerates aging without affecting proliferative growth or viability. Genetic and biochemical criteria reveal LS1 to be a weak Top2 poison. Top2 poisons induce the accumulation of covalent Top2-linked DNA double strand breaks that, if left unrepaired, lead to genome instability and death. LS1 is toxic to cells deficient in homologous recombination, suggesting that the damage it induces is normally mitigated by genome maintenance systems. The essential roles of yTop2 in proliferating cells may come with a fitness trade-off in older cells that are less able to sense or repair yTop2-mediated DNA damage. Consistent with this idea, cells live longer when yTop2 expression levels are reduced. These results identify intrinsic yTop2-mediated DNA damage as a potentially manageable cause of aging

    Potential relevance of differential settlements in earthquake-induced liquefaction damage assessment

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    The assessment of vulnerability of buildings subjected to earthquake-induced liquefaction requires the definition of an integrated damage scale accounting both for ground motion damage and ground permanent movements, which cause rigid-body settlement and tilt of the building but also flexural demand on members due to differential settlement of pad footings. Nevertheless, most of the existing procedures for the estimation of differential settlements rely only in soil characteristics, thus neglecting the influence of building stiffness on the soil-structure interaction. In the present work, based on simplified modelling of soil-structure variability and on preliminary assumption of force distributions, representative values of members' demand due to differential settlement are proposed. A simple approach relying on the structure-to-soil stiffness ratio and the equivalent soil degradation extent under pad footings is adopted. The methodology is calibrated by means of a parametric linear analysis for a set of planar frames. Relative flexural demand due to differential settlements normalised to the seismic flexural demand are obtained. Results show that their relevance may not be very severe, thus damage assessment of differential settlements could be likely accounted separately from flexural and rigid-body demand

    Multiple Tyrosine Residues Contribute to GABA Binding in the GABA_C Receptor Binding Pocket

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    The ligand binding site of Cys-loop receptors is dominated by aromatic amino acids. In GABA_C receptors, these are predominantly tyrosine residues, with a number of other aromatic residues located in or close to the binding pocket. Here we examine the roles of these residues using substitution with both natural and unnatural amino acids followed by functional characterization. Tyr198 (loop B) has previously been shown to form a cation−π interaction with GABA; the current data indicate that none of the other aromatic residues form such an interaction, although the data indicate that both Tyr102 and Phe138 may contribute to stabilization of the positively charged amine of GABA. Tyr247 (loop C) was very sensitive to substitution and, combined with data from a model of the receptor, suggest a π–π interaction with Tyr241 (loop C); here again functional data show aromaticity is important. In addition the hydroxyl group of Tyr241 is important, supporting the presence of a hydrogen bond with Arg104 suggested by the model. At position Tyr102 (loop D) size and aromaticity are important; this residue may play a role in receptor gating and/or ligand binding. The data also suggest that Tyr167, Tyr200, and Tyr208 have a structural role while Tyr106, Trp246, and Tyr251 are not critical. Comparison of the agonist binding site “aromatic box” across the superfamily of Cys-loop receptors reveals some interesting parallels and divergences

    Reflections on the role of the ‘users’: challenges in a multi-disciplinary context of learner-centred design for children on the autism spectrum

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    Technology design in the field of human–computer interaction has developed a continuum of participatory research methods, closely mirroring methodological approaches and epistemological discussions in other fields. This paper positions such approaches as examples of inclusive research (to varying degrees) within education, and illustrates the complexity of navigating and involving different user groups in the context of multi-disciplinary research projects. We illustrate this complexity with examples from our recent work, involving children on the autism spectrum and their teachers. Both groups were involved in learner-centred design processes to develop technologies to support social conversation and collaboration. We conceptualize this complexity as a triple-decker ‘sandwich’ representing Theory, Technologies and Thoughts and argue that all three layers need to be appropriately aligned for a good quality ‘product’ or outcome. However, the challenge lies in navigating and negotiating all three layers at the same time, including the views and experiences of the learners. We question the extent to which it may be possible to combine co-operative, empowering approaches to participatory design with an outcome-focused agenda that seeks to develop a robust learning technology for use in real classrooms

    Life in lockdown:A longitudinal study investigating the impact of the UK COVID-19 lockdown measures on lifestyle behaviours and mental health.

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    BACKGROUND: The COVID-19 pandemic led to the UK government enforcing lockdown restrictions to control virus transmission. Such restrictions present opportunities and barriers for physical activity and healthy eating. Emerging research suggests that in the early stages of the pandemic, physical activity levels decreased, consumption of unhealthy foods increased, while levels of mental distress increased. Our aims were to understand patterns of diet, physical activity, and mental health during the first lockdown, how these had changed twelve-months later, and the factors associated with change. METHODS: An online survey was conducted with UK adults (N = 636; 78% female) during the first national lockdown (May–June 2020). The survey collected information on demographics, physical activity, diet, mental health, and how participants perceived lifestyle behaviours had changed from before the pandemic. Participants who provided contact details were invited to complete a twelve-month follow-up survey (May–June 2021), 160 adults completed the survey at both time-points. Descriptive statistics, T-tests and McNemar Chi Square statistics were used to assess patterns of diet, physical activity, and mental health at baseline and change in behaviours between baseline and follow-up. Linear regression models were conducted to explore prospective associations between demographic and psycho-social variables at baseline with change in healthy eating habit, anxiety, and wellbeing respectively. RESULTS: Between baseline and follow-up, healthy eating habit strength, and the importance of and confidence in eating healthily reduced. Self-rated health (positively) and confidence in eating healthily (negatively) were associated with change in healthy eating habit. There were no differences between baseline and follow-up for depression or physical activity. Mean anxiety score reduced, and wellbeing increased, from baseline to follow-up. Living with children aged 12–17 (compared to living alone) was associated with an increase in anxiety, while perceiving mental health to have worsened during the first lockdown (compared to staying the same) was associated with reduced anxiety and an increase in mental wellbeing. CONCLUSIONS: While healthy eating habits worsened in the 12 months since the onset of the pandemic, anxiety and mental wellbeing improved. However, anxiety may have increased for parents of secondary school aged children. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-022-13888-1
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