Journey to the M_BH -sigma relation: the fate of low mass black holes in the Universe

In this paper, we explore the establishment and evolution of the empirical correlation between black hole mass and velocity dispersion with redshift. We track the growth and accretion history of massive black holes starting from high redshift using two seeding models:(i) Population III remnants, and (ii) massive seeds from direct gas collapse. Although the seeds do not initially satisfy the $M_{\rm BH} - \sigma$ relation, the correlation is established and maintained at all times if self-regulating accretion episodes are associated with major mergers. The massive end of the $M_{\rm BH} - \sigma$ relation is established early, and lower mass MBHs migrate over time. How MBHs migrate toward the relation, the slope and the scatter of the relation all depend critically on the seeding model as well as the adopted self-regulation prescription. We expect flux limited AGN surveys and LISA to select accreting and merging MBHs respectively that have already migrated onto the \msigma relation. This is a consequence of major mergers being more common at high redshift for the most massive, biased, galaxies that anchor the \msigma relation early. We also predict the existence of a large population of low mass `hidden' MBHs at high redshift which can easily escape detection. Additionally, we find that if MBH seeds are massive, $\sim 10^5 M_{\odot}$, the low-mass end of the \msigma flattens towards this asymptotic value, creating a characteristic `plume'.Comment: 8 pages, 5 figures, MNRAS in pres

Generation of Particles and Seeding

One of the most important elements in laser velocimetry, yet the most neglected, is the small particle embedded in the flow field that scatters the light necessary to make velocity measurements. An attempt to remove the confusion in choosing a seeding method by assessing many of the techniques currently used is presented. Their characteristics and typical limitations imposed by various applications are outlined. The ramifications of these methods on measurement accuracy are addressed

Effective information and the influence of an extension event on perceptions and adoption

Perceptions are known to play an important role in the innovation adoption decision. Once influential perceptions have been identified, there is the potential for information to influence adoption by changing these perceptions. In this paper, the influence of an extension workshop targeting grain growers’ perceptions known to be associated with the adoption of integrated weed management and herbicide resistance management has been measured using regression analysis. Consistent with a Bayesian learning framework, the greatest influence on grower perceptions and intended adoption behaviour was observed where information could be delivered with a high degree of certainty and validity.Crop Production/Industries, Farm Management,

Fuzzy Fibers: Uncertainty in dMRI Tractography

Fiber tracking based on diffusion weighted Magnetic Resonance Imaging (dMRI) allows for noninvasive reconstruction of fiber bundles in the human brain. In this chapter, we discuss sources of error and uncertainty in this technique, and review strategies that afford a more reliable interpretation of the results. This includes methods for computing and rendering probabilistic tractograms, which estimate precision in the face of measurement noise and artifacts. However, we also address aspects that have received less attention so far, such as model selection, partial voluming, and the impact of parameters, both in preprocessing and in fiber tracking itself. We conclude by giving impulses for future research

The Illusion of Sustainability

The history of foreign development assistance is one of movement away from addressing immediate needs and toward focusing on the underlying causes of poverty. A recent manifestation is the move towards sustainability,' which stresses community mobilization, education, and cost-recovery. This stands in contrast to the traditional economic analysis of development projects, with its focus on providing public goods and correcting externalities. We examine evidence from randomized evaluations on strategies for combating intestinal worms, which affect one in four people worldwide. Providing medicine to treat worms was extremely cost effective, although medicine must be provided twice per year indefinitely to keep children worm-free. An effort to promote sustainability by educating Kenyan schoolchildren on worm prevention was ineffective, and a mobilization' intervention from psychology failed to boost deworming drug take-up. Take-up was highly sensitive to drug cost: a small increase in cost led to an 80 percent reduction in take-up (relative to free treatment). The results suggest that, in the context we examine, the pursuit of sustainability may be an illusion, and that in the short-run, at least, external subsidies will remain necessary.

The influence of social pressure and nationality on individual decisions: evidence from the behaviour of referees

This study considers the influences on agents’ decisions in an international context. Using data from six seasons of European cup matches it is found that football referees favour home teams when awarding yellow and red cards. Previous research on referee decisions in national leagues has identified social pressure as a key reason for favouritism. While social pressure is also found to be an important influence in this study, the international context reveals that referee decisions are also influenced by the nationality of the referee and team, and the reputation of the league.

The importance of time in referee home bias due to social pressure. Evidence from Spanish football

This paper analyses referee home bias due to social pressure with data from the matches played in the First Division of the Spanish football league between the 2002/03 and 2009/10 seasons. Finally, our main conclusion is that the time the referee has to make a decision does affect the final outcome; while there is no referee home bias when a free kick is awarded, in the case of booking players, when the referee has more time to make a decision, social pressure can influence the final outcome in favour of the home team.Social pressure; crowd effect; referee home bias; sports economics.

The Influence of Social Pressure and Nationality on Individual Decisions: Evidence from the Behaviour of Referees

This study considers the influences on agents’ decisions in an international context. Using data from five seasons of European cup matches it is found that football referees favour home teams when awarding yellow and red cards. Previous research on referee decisions in national leagues has identified social pressure as a key reason for favouritism. While social pressure is also found to be an important influence in this study, the international context reveals that referee decisions are also influenced by the nationality of the referee and club, and the reputation of the league.social pressure, decision-making, referee behaviour, home bias, football