The Place of the Hoplocarida in the Malacostracan Pantheon

The stomatopod body plan is highly specialized for predation, yet the Superorder Hoplocarida originated from something other than the lean, mean, killing machine seen today. The fossil record of the group indicates that it originated early on from a non-raptorial ancestor, with the specialized predatory morphology developing much later. The Recent Hoplocarida have been variously positioned within the Malacostraca, from a Subclass equal in rank to the Eumalacostraca (= Caridoida) to being placed as a Superorder within the Eumalacostraca. Consideration of the early fossil morphology, especially of the form of the carapace, of the position and functioning of the articles in the last three pairs of thoracopods, and of other features, suggests that hoplocarids are early derivatives of a basal eumalacostracan stock that was shrimp-like in form. The enhancement of an abdominal respiratory system most likely allowed the development of the anterior thorax into the specialized raptorial system present today

Global Kinetic Model of a Three-Way-Catalyst-Coated Gasoline Particulate Filter: Catalytic Effects of Soot Accumulation

In the present study, a global kinetic model of three-way-catalyst-coated gasoline particulate filters was developed to understand the relevant kinetic mechanisms taking place both in clean and real soot-loaded filters. The model involves reaction rate expressions for CO, C2H4, and C7H8 conversion over a model Pd/CeZr/Al2O3 catalyst, hydrothermally treated at 650 \ub0C. Particularly, a new rate expression was proposed for ethylene based on the distinctive experimental trends observed for this hydrocarbon. The model predicted satisfactorily the conversion of all three reductants under different experimental conditions. The soot inhibition effect was also modeled by the reduction of the number of active sites. Interestingly, ethylene was less affected compared to other reductants by the presence of soot due to the formation of less stable and more reactive species on the catalyst surface

Recentering open for those at the margins: three lenses on lurking

The group presenting this session was formed through a serendipitous participation in a ‘slow chat’ (#HEdigID) on the topic of OEP. The chat went on long beyond its official end, and we realized that the #HEdigID network was larger than we had observed. It included ‘invisible’ participants who were simply listening, or tuning in once in a while. We began to discuss the practice of ‘lurking’ and the idea of ‘the lurker’. The group conversation which followed revealed some of the complexities of lurking behaviours. What (or who) is a “lurker”? Do we need to rethink what participation means? Why some learners are visible, and others less visible or maybe invisible, remaining on the margins of online and networked learning? Do we need to recenter participation in open spaces – to bring in those who appear to choose to stay on the periphery? It seems there is a need to turn a critical lens onto our assumptions, and think about how ‘privileging the visible’ may constrain and exclude more invisible learners equally interested in learning (Honeychurch et al., 2017; Popovac, M., & Fullwood, C., 2018). Against a prior emphasis on transmission of knowledge, designing for learning in today’s open environments is often ‘designing for participation’. Has the pendulum now swung too far in this direction, such that those who are said to ‘lurk’ are dismissed, derided, or at best, understood through a deficit model? Our proposed lenses on lurking as troublesome, political and ordinary, suggest alternative ways of understanding lurking behaviours, but do not provide an obvious answer to the question of how to engage the lurking learner – or whether the lurker must be engaged. What does learner agency look like in this context? Can we truly design for all? Or should we design for participation – and let lurkers lurk? We are seeking input from participants in online learning spaces – current students or teachers or people who have other roles or with an interest in learning in open environments. Through the discussion/activity, further insights into both the ‘lurker experience’ and inclusive learning design will emerge

Leaching of a low-grade, copper-nickel sulfide ore. 1. Key parameters impacting on Cu recovery during column bioleaching

This study was prompted by the disparate recoveries of nickel (>70%) and copper (<20%) from a test heap of copper-nickel sulfide ore after about 200 days of leaching. Variables tested in bioleaching columns charged with a pyrrhotite-rich, chalcopyrite and pentlandite ore were acid pre-conditioning, inoculation and aeration. The results indicated that the rapid reaction of pyrrhotite with acid created conditions that impacted directly and/or indirectly on copper recovery. Important reactions were hydrogen sulfide formation, high soluble iron concentrations and the formation of large amounts of elemental sulfur. It was hypothesized that copper loss, evidenced by copper re-distribution during passage through the ore, was mainly the result of reaction with hydrogen sulfide to form covellite, although this could not be confirmed by XRD analysis of leached residues. A layer of iron-oxy-hydroxy-sulfate 'scale' on particle surfaces encapsulated sulfide grains as well as elemental sulfur formed by the oxidation of pyrrhotite and was of sufficient depth and integrity to have hindered but not prevented leaching and bioleaching. Lack of aeration (oxygen, carbon dioxide) impacted on ferrous ion biooxidation and probably sulfur biooxidation. More extensive sulfur biooxidation to form acid might have lowered the solution pH and reduced the amount of scale formation, resulting in higher ferric ion concentrations and better chalcopyrite oxidation

VelociWatch: Designing and evaluating a virtual keyboard for the input of challenging text

© 2019 Association for Computing Machinery. Virtual keyboard typing is typically aided by an auto-correct method that decodes a user’s noisy taps into their intended text. This decoding process can reduce error rates and possibly increase entry rates by allowing users to type faster but less precisely. However, virtual keyboard decoders sometimes make mistakes that change a user’s desired word into another. This is particularly problematic for challenging text such as proper names. We investigate whether users can guess words that are likely to cause auto-correct problems and whether users can adjust their behavior to assist the decoder. We conduct computational experiments to decide what predictions to ofer in a virtual keyboard and design a smartwatch keyboard named VelociWatch. Novice users were able to use the features of VelociWatch to enter challenging text at 17 words-per-minute with a corrected error rate of 3%. Interestingly, they wrote slightly faster and just as accurately on a simpler keyboard with limited correction options. Our fnding suggest users may be able to type dif-fcult words on a smartwatch simply by tapping precisely without the use of auto-correct

Exploring perceived legitimacy of traffic law enforcement

The purpose of traffic law enforcement is to encourage compliant driver behaviour. That is, the threat of an undesirable sanction encourages drivers to comply with traffic laws. However, not all traffic law violations are considered equal. For example, while drink driving is generally seen as socially unacceptable, behaviours such as speeding are arguably less so, and speed enforcement is often portrayed in the popular media as a means of “revenue raising”. The perceived legitimacy of traffic law enforcement has received limited research attention to date. Perceived legitimacy of traffic law enforcement may influence (or be influenced by) attitudes toward illegal driving behaviours, and both of these factors are likely to influence on-road driving behaviour. This study aimed to explore attitudes toward a number of illegal driving behaviours and traffic law enforcement approaches that typically target these behaviours using self-reported data from a large sample of drivers. The results of this research can be used to inform further research in this area, as well as the content of public education and advertising campaigns designed to influence attitudes toward illegal driving behaviours and perceived legitimacy of traffic law enforcement

In the blink of an eye: The circadian effects on ocular and subjective indices of driver sleepiness

Driver sleepiness contributes substantially to fatal and severe crashes and the contribution it makes to less serious crashes is likely to as great or greater. Currently, drivers’ awareness of sleepiness (subjective sleepiness) remains a critical component for the mitigation of sleep-related crashes. Nonetheless, numerous calls have been made for technological monitors of drivers’ physiological sleepiness levels so drivers can be ‘alerted’ when approaching high levels of sleepiness. Several physiological indices of sleepiness show potential as a reliable metric to monitor drivers’ sleepiness levels, with eye blink indices being a promising candidate. However, extensive evaluations of eye blink measures are lacking including the effects that the endogenous circadian rhythm can have on eye blinks. To examine the utility of ocular measures, 26 participants completed a simulated driving task while physiological measures of blink rate and duration were recorded after partial sleep restriction. To examine the circadian effects participants were randomly assigned to complete either a morning or an afternoon session of the driving task. The results show subjective sleepiness levels increased over the duration of the task. The blink duration index was sensitive to increases in sleepiness during morning testing, but was not sensitive during afternoon testing. This finding suggests that the utility of blink indices as a reliable metric for sleepiness are still far from specific. The subjective measures had the largest effect size when compared to the blink measures. Therefore, awareness of sleepiness still remains a critical factor for driver sleepiness and the mitigation of sleep-related crashes