Potential use of thermally desorbed soil as a partial cement replacement

The industrial heritage of the UK has given rise to around 100,000 sites, being classified as contaminated. There are many different techniques that have recently been developed to remediate land. Thermal desorption is one of these techniques. Contaminants in the soil are volatilised, which are then removed by a thermal or catalytic oxidiser. The chemical and physical properties of the ‘burnt’ soil’, termed thermally desorbed soil (TDS), have significantly changed but is typically still disposed of to landfill. The use of supplementary cementing materials has become a central aspect of construction economics and environmental preservation. This study therefore investigated the potential use of TDS as a partial cement replacement material. Cement was replaced from 0% (as the control) to 30% TDS in 10% increments. The compressive strength of the mortar cubes was then determined at intervals of 7, 28 and 91 days. For a direct comparison, a well-established pozzolanic material, fly ash (FA) was tested throughout the programme. Strength was indirectly related to replacement level, with the control initially (up to 7 days) gaining, and thereafter retaining, the highest degree of strength. However, after 7 days the rate of gain in strength was higher for the replacement mixes (FA and TDS) than the control. There was no significant strength difference between the FA and TDS mixes up to 20% replacement. Hence, based on these initial strength results, the performance of TDS as a partial cement replacement (up to 20%) was directly equivalent to that of FA. Environmental benefits for the use of TDS as a partial cement replacement would be twofold; firstly, by using a waste material rather than disposing to landfill; and secondly by using less cement. This would result in less carbon dioxide (CO2) being released into the atmosphere during the cement manufacturing process, which is currently responsible for 7–10% of the global CO2 emissions

It's Good to Be First: Order Bias in Reading and Citing NBER Working Papers

When choices are made from ordered lists, individuals can exhibit biases toward selecting certain options as a result of the ordering. We examine this phenomenon in the context of consumer response to the ordering of economics papers in an e-mail announcement issued by the NBER. We show that despite the effectively random list placement, papers listed first each week are about 30% more likely to be viewed, downloaded, and subsequently cited. We suggest that a model of “skimming” behavior, where individuals focus on the first few papers in the list due to time constraints, would be most consistent with our findings

Motor contributions to the perception of relative phase

The extent to which different stimulus elements move together, namely their relative phase, is a central visual feature of many social and physical systems; characterizing everything from the oscillations of a walker's limbs to the alternating lights at pedestrian crossings. The experiments described here provide the first evidence of a motor contribution to the representation of relative phase. Using an interference paradigm, we demonstrate that a motor load dramatically impairs discrimination of relative phase. Comparable interference effects were observed for biological and mechanical stimuli, indicative of a domain-general mechanism. In addition, we show that the same motor load has little effect on a similar static-angle matching task, and that an auditory rhythmic load did not interfere with phase discriminations in the same way as the motor load. These results suggest that the motor system contributes to the perception of relative phase; information crucial for interpreting our social and physical environments. (PsycINFO Database Record (c) 2014 APA, all rights reserved)

Colocation and Scientific Collaboration: Evidence from a Field Experiment

We present the results of a field experiment conducted within the Harvard Medical School system of hospitals and research centers to understand how colocation impacts the likelihood of scientific collaboration. We introduce exogenous colocation and face-to-face interactions for a random subset of biomedical researchers responding to an opportunity to apply for a research grant. While the overall baseline likelihood of any two researchers collaborating is small, we find that random colocation significantly increases the likelihood of pair-level co-application by almost 70%. The effect of exogenous colocation on subsequent collaboration was greater for previous coauthors, pairs including a woman, and pairs researching similar clinical areas. Our results suggest that matching between scientists may be subject to considerable frictions—even among those in relatively close geographic proximity and in the same organizational system. At the same time, even a brief and focused intervention facilitating face-to-face interactions can provide information that impacts the formation of scientific collaborations

The Acute Effects of a Dopamine D3 Receptor Preferring Agonist on Motivation for Cigarettes in Dependent and Occasional Cigarette Smokers

Background: Dopaminergic functioning is thought to play critical roles in both motivation and addiction. There is preliminary evidence that dopamine agonists reduce the motivation for cigarettes in smokers. However, the effects of pramipexole, a dopamine D3 receptor preferring agonist, have not been investigated. The aim of this study was to examine the effects of an acute dose of pramipexole on the motivation to earn cigarettes and nondrug rewards. Methods: Twenty dependent and 20 occasional smokers received 0.5 mg pramipexole using a double-blind, placebo-controlled crossover design. Motivation for cigarettes and consummatory nondrug rewards was measured using the DReaM-Choice task, in which participants earned, and later "consumed," cigarettes, music, and chocolate. Demand for cigarettes was measured using the Cigarette Purchase Task (CPT). Self-reported craving, withdrawal, and drug effects were also recorded. Results: Dependent smokers chose (p < .001) and button-pressed for (p < .001) cigarettes more, and chose chocolate less (p < .001), than occasional smokers. Pramipexole did not affect the number of choices for or amount of button-pressing for any reward including cigarettes, which was supported by a Bayesian analysis. The dependent smokers had greater demand for cigarettes than occasional smokers across all CPT outcomes (ps < .021), apart from elasticity. Pramipexole did not affect demand for cigarettes, and this was supported by Bayesian analyses. Pramipexole produced greater subjective "feel drug" and "dislike drug" effects than placebo. Conclusions: Dependent and occasional cigarette smokers differed in their motivation for cigarettes but not for the nondrug rewards. Pramipexole did not acutely alter motivation for cigarettes. These findings question the role of dopamine D3 receptors in cigarette-seeking behavior in dependent and occasional smokers. Implications: This study adds to the growing literature about cigarette versus nondrug reward processing in nicotine dependence and the role of dopamine in cigarette-seeking behavior. Our results suggest nicotine dependence is associated with a hypersensitivity to cigarette rewards but not a hyposensitivity to nondrug rewards. Furthermore, our results question the importance of dopamine D3 receptors in motivational processing of cigarettes in occasional and dependent smokers

From Crowds to Collaborators: Initiating Effort & Catalyzing Interactions Among Online Creative Workers

Online collaborative platforms have emerged as a complementary approach to traditional organizations for coordinating the collective efforts of creative workers. However, it is surprising that they result in any productive output as individuals often work without direct monetary incentives while collaborating with unknown others. In this paper, we distinguish the conditions necessary for eliciting effort from those affecting the quality of interdependent teamwork. We consider the role of incentives versus social processes in catalyzing collaboration. We test our hypotheses using a unique data set of 260 individuals randomly assigned to 52 teams tasked with developing working solutions to a complex innovation problem over 10 days, with varying monetary incentives. We find that levels of effort are driven by cash incentives and the presence of other interacting teammates. The level of collaboration, by contrast, was not sensitive to cash incentives. Instead, individuals increased their communication if teammates were also actively participating. Additionally, team performance is uniquely driven by the level of emergent interdependence, as indexed by the diversity of topics discussed and the temporal coordination of activity in short focused time periods. Our results contribute to the literature on how alternative organizational forms can be designed to solve complex innovation tasks

A comparison of approaches to documentary photography of 1930s America and contemporary South Africa.

A dissertation submitted to the Faculty of Arts, University of the Witwatersrand, Johannesburg, in partlal fulfilment of the requirements for the degree of Master of Arts in Fine Arts.The research for this degree comprises a theoretical dissertation and a practical component of photographs. The theoretical research investigates the practice of documentary photography in America and South Africa. The photographs of Walker Evans, Robert Frank, David Goldblatt and Bob Gosanl are examined against the background of two organisations, the Farm Security Administration and Drum. These organisations influenced the documentary genre in their respective countries because of their socio-polltical concerns: their choice and presentation of subject matter for publication influenced both the photographar and the viewer. Documentary photographs appear, because of their seemingly candid and unmediated nature, to present historically factual images. Examples from the work of the four photographers reveal their distinction from, continuity with the confines of the documentary genre. Their respective approaches reveal the role of perception as it manifests itself in their work. Subjugation, attltudes towards subject matter, and the pictorial construction of images are analysed in relation to each photographer's work. The relationship of image and text in documentary photography is seen as an element of intervention by the photographer. The selection of these photographers was motivated for their partinance to the subject matter and to the pictorial considerations of the candidate. These issues are therefore examined in relation to the candidate's approach to photography.Andrew Chakane 201

How Do Travel Costs Shape Collaboration?

We develop a simple theoretical framework for thinking about how geographicfrictions, and in particular travel costs, shape scientists’collaboration decisions and thetypes of projects that are developed locally versus over distance. We then take advantageof a quasi-experiment—the introduction of new routes by a low-cost airline—to test thepredictions of the theory. Results show that travel costs constitute an important friction tocollaboration: after a low-cost airline enters, the number of collaborations increases be-tween 0.3 and 1.1 times, a result that is robust to multiple falsification tests and causal innature. The reduction in geographic frictions is particularly beneficial for high-qualityscientists that are otherwise embedded in worse local environments. Consistent with thetheory, lower travel costs also endogenously change the types of projects scientists engagein at different levels of distance. After the shock, we observe an increase in higher-qualityand novel projects, as well as projects that take advantage of complementary knowledgeand skills between subfields, and that rely on specialized equipment. We test the gen-eralizability of ourfindings from chemistry to a broader data set of scientific publicationsand to a differentfield where specialized equipment is less likely to be relevant, mathe-matics. Last, we discuss implications for the formation of collaborative research and de-velopment teams over distance

You Can\u27t Hide Your Lyin\u27 Eyes: The Uses Of Deception In Romantic Relationships

A purpose of this study was to further the literature regarding the use of deceptive affection in romantic relationships. This study picks up where previous research left off in that it aimed to identify relational outcomes that may be associated with the use of deceptive affection. This study sought to identify deceptive affectionate behaviors and their role in romantic relationships. Two measures were created; a scale to measure DAMs and a scale to measure WAs, both proved to be reliable. Results from the study provided additional items to be included in the measures going forward. The study did add to the existing literature for use of DAMs and WAs, though the results were not consistent with previous research and the hypothesis. However, the results indicated that deceptive affection is negatively associated with relational outcomes. These results provide an opportunity to further explore the purpose of deceptive affection in romantic relationships