Propagating Stress-Strain Curve Variability in Multi-Material Problems: Temperature-Dependent Material Tests to Plasticity Models to Structural Failure Predictions

This chapter presents a practical methodology for characterizing and propagating the effects of temperature-dependent material strength and failure-criteria variability to structural model predictions. The application involves a cylindrical canister (“can”) heated and pressurized to failure. Temperature dependence and material sample-to-sample stochastic variability are inferred from very limited experimental data of a few replicate uniaxial tension tests at each of seven temperatures spanning the 800°C temperature excursion experienced by the can, for each of several stainless steel alloys that make up the can. The load-displacement curves from the material tests are used to determine effective temperature-dependent stress-strain relationships in ductile-metal plasticity models used in can-level model predictions. Particularly challenging aspects of the problem are the appropriate inference, representation, and propagation of temperature dependence and material stochastic variability from just a few experimental data curves at a few temperatures (as sparse discrete realizations or samples from a random field of temperature-dependent stress-strain behavior), for multiple such materials involved in the problem. Currently unique methods are demonstrated that are relatively simple and effective

Period, Theme, Event: Locating Information History in History

Explores 'information history', or the study of information and its practices, as a way to arrange investigations of past and present. An invited contribution for the volume, "Information and Power in History: Towards a Global Approach," edited by Ida Nijenhuis, Marijke van Faassen, Joris Gijsenbergh, Wim de Jong, and Ronald Sluijter (London: Routledge, forthcoming). A submitted manuscript under review

Foundations of the DEFT Project: tertiary educators Developing Expertise Fostering Thinking

We describe the rationale, creation, and activity of a long-term co-constructed voluntary professional development initiative for tertiary educators. This is a Community of Practice (CoP) formed to investigate “thinking” as a topic which may be explicitly taught. The aim of this paper is to share the value of this CoP in one context and insights into how similar approaches may be useful to other tertiary educators. The project has run for a year to date, involving a small but growing collective of tertiary educators, with members from one Canadian and several Australian Universities. Our methodology is participatory: we regularly meet, reflect, and record our reflections. Our records contain data relating to our motivation, our insights, and the impact of these upon our choices in our teaching practices. In particular, our rationale includes the mutual desire to invest in developing understanding of our teaching challenges, to enable us to create thoughtful teaching approaches fit for our purposes and contexts. Hence, the central focus of our CoP is the Development of our Expertise in Fostering Thinking (DEFT). This focus has illuminated gaps in existing scholarly literature pertaining to communal development of theory, personal development of schemata, capacity for reflexivity, and instantiation in our disciplines. Opportunities and risks associated with our other sources of professional learning are identified and discussed. We elaborate on a double-layered approach, in which we explore the construction of our own schemata as a precursor to helping students build their schemata as a foundation for their own understanding, and the role of flexible, critical, and creative thinking on our part. We utilise the scholarship of expertise, frequently returning to such questions as “How do we know what our students are thinking?” Insights gleaned from our reflections are shared, and recommendations are presented on the formation of similar projects

Analysis of host responses to Mycobacterium tuberculosis antigens in a multi-site study of subjects with different TB and HIV infection states in sub-Saharan Africa.

BACKGROUND: Tuberculosis (TB) remains a global health threat with 9 million new cases and 1.4 million deaths per year. In order to develop a protective vaccine, we need to define the antigens expressed by Mycobacterium tuberculosis (Mtb), which are relevant to protective immunity in high-endemic areas. METHODS: We analysed responses to 23 Mtb antigens in a total of 1247 subjects with different HIV and TB status across 5 geographically diverse sites in Africa (South Africa, The Gambia, Ethiopia, Malawi and Uganda). We used a 7-day whole blood assay followed by IFN-γ ELISA on the supernatants. Antigens included PPD, ESAT-6 and Ag85B (dominant antigens) together with novel resuscitation-promoting factors (rpf), reactivation proteins, latency (Mtb DosR regulon-encoded) antigens, starvation-induced antigens and secreted antigens. RESULTS: There was variation between sites in responses to the antigens, presumably due to underlying genetic and environmental differences. When results from all sites were combined, HIV- subjects with active TB showed significantly lower responses compared to both TST(-) and TST(+) contacts to latency antigens (Rv0569, Rv1733, Rv1735, Rv1737) and the rpf Rv0867; whilst responses to ESAT-6/CFP-10 fusion protein (EC), PPD, Rv2029, TB10.3, and TB10.4 were significantly higher in TST(+) contacts (LTBI) compared to TB and TST(-) contacts fewer differences were seen in subjects with HIV co-infection, with responses to the mitogen PHA significantly lower in subjects with active TB compared to those with LTBI and no difference with any antigen. CONCLUSIONS: Our multi-site study design for testing novel Mtb antigens revealed promising antigens for future vaccine development. The IFN-γ ELISA is a cheap and useful tool for screening potential antigenicity in subjects with different ethnic backgrounds and across a spectrum of TB and HIV infection states. Analysis of cytokines other than IFN-γ is currently on-going to determine correlates of protection, which may be useful for vaccine efficacy trials

Trial Protocol: Randomised controlled trial of the effects of very low calorie diet, modest dietary restriction, and sequential behavioural programme on hunger, urges to smoke, abstinence and weight gain in overweight smokers stopping smoking

Background\ud Weight gain accompanies smoking cessation, but dieting during quitting is controversial as hunger may increase urges to smoke. This is a feasibility trial for the investigation of a very low calorie diet (VLCD), individual modest energy restriction, and usual advice on hunger, ketosis, urges to smoke, abstinence and weight gain in overweight smokers trying to quit. \ud \ud Methods\ud This is a 3 armed, unblinded, randomized controlled trial in overweight (BMI > 25 kg/$m^2$), daily smokers (CO > 10 ppm); with at least 30 participants in each group. Each group receives identical behavioural support and NRT patches (25 mg(8 weeks),15 mg(2 weeks),10 mg(2 weeks)). The VLCD group receive a 429-559 kcal/day liquid formula beginning 1 week before quitting and continuing for 4 weeks afterwards. The modest energy restricted group (termed individual dietary and activity planning(IDAP)) engage in goal-setting and receive an energy prescription based on individual basal metabolic rate(BMR) aiming for daily reduction of 600 kcal. The control group receive usual dietary advice that accompanies smoking cessation i.e. avoiding feeling hungry but eating healthy snacks. After this, the VLCD participants receive IDAP to provide support for changing eating habits in the longer term; the IDAP group continues receiving this support. The control group receive IDAP 8 weeks after quitting. This allows us to compare IDAP following a successful quit attempt with dieting concurrently during quitting. It also aims to prevent attrition in the unblinded, control group by meeting their need for weight management. Follow-up occurs at 6 and 12 months. \ud \ud Outcome measures include participant acceptability, measured qualitatively by semi-structured interviewing and quantitatively by recruitment and attrition rates. Feasibility of running the trial within primary care is measured by interview and questionnaire of the treatment providers. Adherence to the VLCD is verified by the presence of urinary ketones measured weekly. Daily urges to smoke, hunger and withdrawal are measured using the Mood and Physical Symptoms Scale-Combined (MPSS-C) and a Hunger Craving Score (HCS). 24 hour, 7 day point prevalence and 4-week prolonged abstinence (Russell Standard) is confirmed by CO < 10 ppm. Weight, waist and hip circumference and percentage body fat are measured at each visit. \ud \ud Trial Registration\ud Current controlled trials ISRCTN83865809\ud \u

The Vehicle, 1967, Vol. 9 no. 2

Table of Contents Commentarypage 3 SketchAnn Butlerpage 4 I Take A Long-Out-of-Use BookAnthony Griggspage 5 The Leaf StemDianne Cochranpage 6 The Four MusketeersJim Courterpage 7 Status QuoAdrian Beardpage 7 SketchAnn Butlerpage 8 NocturneMike Baldwinpage 9 Oh Impatient HeartK. H. Shariffpage 9 Letter to a FianceeMaurice Snivelypage 10 Listen!Bonnie Blackpage 11 The Water\u27s EdgeStephen W. Gibbspage 12 TogetherDavid Reifpage 13 SketchAnn Butlerpage 14 Evening TimeSharon Nelsonpage 15 Japanese HaikuBev Hensonpage 15 Of Love and WarBruce Czeluscinskipage 16 Always AloneKib Voorheespage 17 the end of loveJackie Bratcherpage 18 1-20-66Sharon Nelsonpage 19 Blessed Are WeBonnie Marie Beckpage 19 The Time To LiveNeil Tracypage 20 Imminent AwakeningHelen Coxpage 21 The Dead Panther LairMolly J. Evanspage 21 Good SheepMike Tilfordpage 22 The Flame of LifeJacki Jacquespage 23 Then Arrives The Day Of DarkMolly J. Evanspage 23 Sketch: To love is to rememberAnn Butlerpage 24 Hidden RiversCharles J. Mertzpage 25 SilenceLinda G. Phillipspage 26 December - 1964Bonnie Blackpage 26 LoveHazel Thomaspage 27 To Praise A Good Man Neil Tracypage 28 Definitions \u2767Sharon Nelsonpage 29 To Wish Is a CrimeBonnie Marie Beckpage 30 College MadhatterMaurice Snivelypage 31 No. 8Sharon Nelsonpage 32 The Open FireSusan Williamspage 32https://thekeep.eiu.edu/vehicle/1017/thumbnail.jp

Canada-Africa Relations in Changing Core-Periphery Dynamics: A Chance to "Come Back" Differently

The Department of Foreign Affairs Canada sees the dynamism at play across the African continent as calling out for Canadian engagement. Africa in the twenty-first century is no longer the continent emerging from colonial rule; it seeks new forms of relationships with international partners. The African Development Bank, for instance, has identified five priorities for inclusive growth on the continent. The challenges are huge, as is the potential for transformative change. But the conditions for international collaboration in achieving these goals have changed; African leaders are seeking new forms of associations and teamwork. Canada has an opportunity to "come back" differently if it can look beyond its narrow mining interests and become an active partner working with public authorities in need of new and bold international partnerships. Unfortunately, Trudeau's "Canada is back" campaign does not look set to change the status quo. And, in a world where the political economic power is moving east, African countries do not have much reason to listen to Canada

Regulation by interdomain communication of a headful packaging nuclease from bacteriophage T4

In genome packaging by tailed bacteriophages and herpesviruses, a concatemeric DNA is cut and inserted into an empty procapsid. A series of cuts follow the encapsidation of each unit-length ‘headful’ genome, but the mechanisms by which cutting is coupled to packaging are not understood. Here we report the first biochemical characterization of a headful nuclease from bacteriophage T4. Our results show that the T4 nuclease, which resides in the C-terminal domain of large ‘terminase’ gp17, is a weak endonuclease and regulated by a variety of factors; Mg, NaCl, ATP, small terminase gp16 and N-terminal ATPase domain. The small terminase, which stimulates gp17-ATPase, also stimulates nuclease in the presence of ATP but inhibits in the absence of ATP suggesting interdomain crosstalk. Comparison of the ‘relaxed’ and ‘tensed’ states of the motor show that a number of basic residues lining the nuclease groove are positioned to interact with DNA in the tensed state but change their positions in the relaxed state. These results suggest that conformational changes in the ATPase center remodel the nuclease center via an interdomain ‘communication track’. This might be a common regulatory mechanism for coupling DNA cutting to DNA packaging among the headful packaging nucleases from dsDNA viruses