Tension Cranes, A Close Collaboration of Architects and Engineers

This set of images and studies proves to show that architects and engineers can indeed work closely to produce amazing and beautiful results. This result came in the form of a project proposal for a high – rise residential tower located in the heart of San Francisco. The team elected to utilize a highly efficient system of cables in order to cantilever over the edges of the site and optimize the air space, make powerful vistas to increase residential value, and to form an elegant structural system holding everything together. In this paper, the design process is explained into engineering, architecture and then how the two have come together to make a compelling project

An investigation of thresholds in air pollution-mortality effects

In this paper we introduce and implement new techniques to investigate threshold effects in air pollution-mortality relationships. Our key interest is in measuring the dose-response relationship above and below a given threshold level where we allow for a large number of potential explanatory variables to trigger the threshold effect. This is in contrast to existing approaches that usually focus on a single threshold trigger. We allow for a myriad of threshold effects within a Bayesian statistical framework that accounts for model uncertainty (i.e. uncertainty about which threshold trigger and explanatory variables are appropriate). We apply these techniques in an empirical exercise using daily data from Toronto for 1992-1997. We investigate the existence and nature of threshold effects in the relationship between mortality and ozone (O3), total particulate matter (PM) and an index of other conventionally occurring air pollutants. In general, we find the effects of the pollutants we consider on mortality to be statistically indistinguishable from zero with no evidence of thresholds. The one exception is ozone, for which results present an ambiguous picture. Ozone has no significant effect on mortality when we exclude threshold effects from the analysis. Allowing for thresholds we find a positive and significant effect for this pollutant when the threshold trigger is the average change in ozone two days ago. However, this significant effect is not observed after controlling for PM

Measuring the health effects of air pollution : to what extent can we really say people are dying from bad air?

Estimation of the effects of environmental impacts is a major focus of current theoretical and policy research in environmental economics. Such estimates are used to set regulatory standards for pollution exposure; design appropriate environmental protection and damage mitigation strategies; guide the assessment of environmental impacts; and measure public willingness to pay for environmental amenities. It is a truism that the effectiveness of such strategies depends crucially on the quality of the estimates used to inform them. However, this paper argues that in respect to at least one area of the empirical literature - the estimation of the health impacts of air pollution using daily time series data - existing estimates are questionable and thus have limited relevance for environmental decision-making. By neglecting the issue of model uncertainty - or which models, among the myriad of possible models researchers should choose from to estimate health effects - most studies overstate confidence in their chosen model and underestimate the evidence from other models, thereby greatly enhancing the risk of obtaining uncertain and inaccurate results. This paper discusses the importance of model uncertainty for accurate estimation of the health effects of air pollution and demonstrates its implications in an exercise that models pollution-mortality impacts using a new and comprehensive data set for Toronto, Canada. The main empirical finding of the paper is that standard deviations for air pollution-mortality impacts become very large when model uncertainty is incorporated into the analysis. Indeed they become so large as to question the plausibility of previously measured links between air pollution and mortality. Although applied to the estimation of the effects of air pollution, the general message of this paper - that proper treatment of model uncertainty critically determines the accuracy of the resulting estimates - applies to many studies that seek to estimate environmental effects

Heterogeneity in the Effect of Common Shocks on Healthcare Expenditure Growth

Health care expenditure growth is affected by important unobserved common shocks such as technological innovation, changes in sociological factors, shifts in preferences and the epidemiology of diseases. While common factors impact in principle all countries, their effect is likely to differ across countries. To allow for unobserved heterogeneity in the effects of common shocks, we estimate a panel data model of health care expenditure growth in 34 OECD countries over the years 1980 to 2012 where the usual fixed or random effects are replaced by a multifactor error structure. We address model uncertainty with Bayesian Model Averaging, to identify a small set of important expenditure drivers from 43 potential candidates. We establish 16 significant drivers of healthcare expenditure growth, including growth in GDP per capita and in insurance premiums, changes in financing arrangements and some institutional characteristics, expenditures on pharmaceuticals, population aging, costs of health administration, and inpatient care. Our approach allows us to derive estimates that are less subject to bias than in previous analyses, and provide robust evidence to policy makers on the drivers that were most strongly associated with the growth in health care expenditures over the past 32 years

Perfectionism worksheets

A series of worksheets on perfectionism

Structure-guided evolution of antigenically distinct adeno-associated virus variants for immune evasion

Preexisting neutralizing antibodies (NAbs) against adeno-associated viruses (AAVs) pose a major, unresolved challenge that restricts patient enrollment in gene therapy clinical trials using recombinant AAV vectors. To tackle this problem, we developed a structure-guided approach to evolve AAV variants with altered antigenic footprints that cannot be recognized by preexisting antibodies. These proof-of-principle studies demonstrate that synthetic AAV variants can be evolved to evade neutralizing sera from different species—mice, nonhuman primates, and humans—without compromising yield and transduction efficiency or altering tropism. Our approach provides a roadmap for engineering any AAV strain to evade NAbs in prospective patients for human gene therapy

Noise-driven oscillations in microbial population dynamics

Microbial populations in the natural environment are likely to experience growth conditions very different from those of a typical laboratory xperiment. In particular, removal rates of biomass and substrate are unlikely to be balanced under realistic environmental conditions. Here, we consider a single population growing on a substrate under conditions where the removal rates of substrate and biomass are not necessarily equal. For a large population, with deterministic growth dynamics, our model predicts that this system can show transient (damped) oscillations. For a small population, demographic noise causes these oscillations to be sustained indefinitely. These oscillations arise when the dynamics of changes in biomass are faster than the dynamics of the substrate, for example, due to a high microbial death rate and/or low substrate flow rates. We show that the same mechanism can produce sustained stochastic oscillations in a two-species, nutrient-cycling microbial ecosystem. Our results suggest that oscillatory population dynamics may be a common feature of small microbial populations in the natural environment, even in the absence of complex interspecies interactions.Comment: 25 pages, 11 figure

Five unsolved issues concerning burnout in athletes: An expert perspective

Introduction: Concern about mental health is an increasingly relevant topic in high-performance sport. In this regard, because burnout can be harmful to both the health and performance of athletes, it is of particular importance. Although a great deal of time and effort has been dedicated to the study of athlete burnout, there are still issues that require further work. Therefore, in the present paper, we aim to highlight what, in our perspective, are the most important unsolved issues regarding burnout in athletes. Methods: We brought together expert athlete burnout scholars to offer their perspectives on five unresolved issues in this research area. Results: We describe the following five issues that require further research attention: (i) burnout as a syndrome, (ii) the negative consequences of burnout, (iii) the role of recovery in burnout, (iv) the importance of the social environment, and (v) developing effective interventions to reduce/prevent burnout. Conclusion: Our commentary provides suggestions for future research to help solve these problems, advance our understanding of athlete burnout, and ultimately safeguard the mental health of athletes

Q methodology and a Delphi poll: a useful approach to researching a narrative approach to therapy

Q methodology and a Delphi poll combined qualitative and quantitative methods to explore definitions of White and Epston's (1990) narrative approach to therapy among a group of UK practitioners. A Delphi poll was used to generate statements about narrative therapy. The piloting of statements by the Delphi panel identified agreement about theoretical ideas underpinning narrative therapy and certain key practices. A wider group of practitioners ranked the statements in a Q sort and made qualitative comments about their sorting. Quantitative methods (principal components analysis) were used to extract eight accounts of narrative therapy, five of which are qualitatively analysed in this paper. Agreement and differences were identified across a range of issues, including the social construction of narratives, privileging a political stance or narrative techniques and the relationship with other therapies, specifically systemic psychotherapy. Q methodology, combined with the Delphi poll, was a unique and innovative feature of this study