Protecting the Privilege of Burning Sugarcane at Harvest

The South African sugar industry burns 90% of the crop at harvest while 10% is harvested green. The trend to burn cane at harvest has increased over the past twenty years, despite growing pressure from the public and environmental legislation. This paper explores the influence that public pressure and legislation are having on the practise of burning and examines the actions that the industry has implemented in order to protect the privilege of burning sugarcane at harvest. A communication model and case studies are used to illustrate the interaction between the sugar industry, government and public role players over cane burning. Communication has proved to be a key management tool that has had to be dynamic and on going in order to engage the various role players effectively. It is presumed that the advantages of burning outweigh those of trashing and it is for the nuisance rather than the health factor that the public want cane burning banned on farms adjacent to residential or tourist areas. The government, however, regards agricultural burning as a contributory factor to high air pollution levels during the winter months and expects these levels to be reduced. Will the public be able to force change to the current practice of burning cane at harvest in the South African sugar industry or will the steps taken by the industry provide adequate protection? Although favourable outcomes have been achieved, cane burning remains under pressure from the public and government.cane burning, communication, environment, legislation, Farm Management,

Effects of landmark distance and stability on accuracy of reward relocation

This work was supported by the University of St Andrews, the University of Lethbridge and the Natural Sciences and Engineering Council of Canada.Although small-scale navigation is well studied in a wide range of species, much of what is known about landmark use by vertebrates is based on laboratory experiments. To investigate how vertebrates in the wild use landmarks, we trained wild male rufous hummingbirds to feed from a flower that was placed in a constant spatial relationship with two artificial landmarks. In the first experiment, the landmarks and flower were 0.25, 0.5 or 1 m apart and we always moved them 3–4 m after each visit by the bird. In the second experiment, the landmarks and flower were always 0.25 m apart and we moved them either 1 or 0.25 m between trials. In tests, in which we removed the flower, the hummingbirds stopped closer to the predicted flower location when the landmarks had been closer to the flower during training. However, while the distance that the birds stopped from the landmarks and predicted flower location was unaffected by the distance that the landmarks moved between trials, the birds directed their search nearer to the predicted direction of the flower, relative to the landmarks, when the landmarks and flower were more stable in the environment. In the field, then, landmarks alone were sufficient for the birds to determine the distance of a reward but not its direction.PostprintPostprintPeer reviewe

The blue stragglers formed via mass transfer in old open clusters

In this paper, we present the simulations for the primordial blue stragglers in the old open cluster M67 based on detailed modelling of the evolutionary processes. The principal aim is to discuss the contribution of mass transfer between the components of close binaries to the blue straggler population in M67. First, we followed the evolution of a binary of 1.4M$_\odot$+0.9M$_\odot$. The synthetic evolutionary track of the binary system revealed that a primordial blue straggler had a long lifetime in the observed blue straggler region of color-magnitude diagram. Second, a grid of models for close binary systems experiencing mass exchange were computed from 1Gyr to 6Gyr in order to account for primordial blue-straggler formation in a time sequence. Based on such a grid, Monte-Carlo simulations were applied for the old open cluster M67. Adopting appropriate orbital parameters, 4 primordial blue stragglers were predicted by our simulations. This was consistent with the observational fact that only a few blue stragglers in M67 were binaries with short orbital periods. An upper boundary of the primordial blue stragglers in the color-magnitude diagram (CMD) was defined and could be used to distinguish blue stragglers that were not formed via mass exchange. Using the grid of binary models, the orbital periods of the primordial BSs could be predicted. Compared with the observations, it is clear that the mechanism discussed in this work alone cannot fully predict the blue straggler population in M67. There must be several other processes also involved in the formation of the observed blue stragglers in M67.Comment: 11 pages, 6 figures, A&A accepte

Wild rufous hummingbirds use local landmarks to return to rewarded locations

This work was supported by the University of St Andrews, the University of Lethbridge and the Natural Sciences and Engineering Council of Canada.Animals may remember an important location with reference to one or more visual landmarks. In the laboratory, birds and mammals often preferentially use landmarks near a goal (“local landmarks”) to return to that location at a later date. Although we know very little about how animals in the wild use landmarks to remember locations, mammals in the wild appear to prefer to use distant landmarks to return to rewarded locations. To examine what cues wild birds use when returning to a goal, we trained free-living hummingbirds to search for a reward at a location that was specified by three nearby visual landmarks. Following training we expanded the landmark array to test the extent that the birds relied on the local landmarks to return to the reward. During the test the hummingbirds' search was best explained by the birds having used the experimental landmarks to remember the reward location. How the birds used the landmarks was not clear and seemed to change over the course of each test. These wild hummingbirds, then, can learn locations in reference to nearby visual landmarks.PostprintPeer reviewe

Discovery of magnetic fields in three He variable Bp stars with He and Si spots

It is essential for the understanding of stellar structure models of high mass stars to explain why constant stars, non-pulsating chemically peculiar hot Bp stars and pulsating stars co-exist in the slowly pulsating B stars and beta Cephei instability strips. We have conducted a search for magnetic fields in the four Bp stars HD55522, HD105382, HD131120, and HD138769 which previously have been wrongly identified as slowly pulsating B stars. A recent study of these stars using the Doppler Imaging technique revealed that the elements He and Si are inhomogeneously distributed on the stellar surface, causing the periodic variability. Using FORS1 in spectropolarimetric mode at the VLT, we have acquired circular polarisation spectra to test the presence of a magnetic field in these stars. A variable magnetic field is clearly detected in HD55522 and HD105382, but no evidence for the existence of a magnetic field was found in HD131120. The presence of a magnetic field in HD138769 is suggested by one measurement at 3 sigma level. We discuss the occurence of magnetic B stars among the confirmed pulsating B stars and find strong magnetic fields of order kG and oscillations to be mutually exclusive.Comment: 5 pages, 3 figures, 2 tables, accepted for publication in A

Why study cognition in the wild (and how to test it)?

An animal's behavior is affected by its cognitive abilities, which are, in turn, a consequence of the environment in which an animal has evolved and developed. Although behavioral ecologists have been studying animals in their natural environment for several decades, over much the same period animal cognition has been studied almost exclusively in the laboratory. Traditionally, the study of animal cognition has been based on well-established paradigms used to investigate well-defined cognitive processes. This allows identification of what animals can do, but may not, however, always reflect what animals actually do in the wild. As both ecologists and some psychologists increasingly try to explain behaviors observable only in wild animals, we review the different motivations and methodologies used to study cognition in the wild and identify some of the challenges that accompany the combination of a naturalistic approach together with typical psychological testing paradigms. We think that studying animal cognition in the wild is likely to be most productive when the questions addressed correspond to the species’ ecology and when laboratory cognitive tests are appropriately adapted for use in the field. Furthermore, recent methodological and technological advances will likely allow significant expansion of the species and questions that can be addressed in the wild.PostprintPostprintPeer reviewe

Pulsational line profile variation of the roAp star HR 3831

We report the first comprehensive investigation of the line profile variation caused by non-radial pulsation in a magnetic oscillating chemically peculiar star. Spectrum variation of the well-known roAp star HR 3831 is detected using very high-resolution high signal-to-noise spectroscopic time-series observations and are followed through the whole rotation cycle of the star. We confirm outstanding diversity of pulsational behaviour of different lines in the HR 3831 spectrum and attribute this phenomenon to an interplay between extreme vertical chemical inhomogeneity of the HR 3831 atmosphere and a running pulsation wave, propagating towards the upper photospheric layers with increasing amplitude. Rapid profile variation of the NdIII 6145 A line is characterized by measuring changes of its equivalent width and the first three moments. We demonstrate that rotational modulation of the radial velocity oscillations cannot be fully explained by an oblique axisymmetric dipole (ell=1, m=0) mode, implied by the classical oblique pulsator model of roAp stars. Pulsational variation of the higher moments reveal substantial contribution of the high-order (ell=3) spherical harmonics which appear due to distortion of pulsations in HR 3831 by the global magnetic field. We interpret observations with a novel numerical model of the pulsational variation and rotational modulation of the line profile moments in roAp stars. The comparison between observed and computed amplitudes and phases of the radial velocity and line width variation is used to establish parameters of the oblique pulsator model of HR 3831. Furthermore, definite detection of pulsational variation in lines of light and iron-peak elements enables the first 3-D mapping of pulsations in non-radially oscillating star.Comment: 21 pages, 11 figures; accepted by A&

Assessment of health in human faces is context-dependent

This work was supported by the National Environment Research Council, UK (KM), Unilever Research & Development USA and the Economic and Social Research Council (RW, DP).When making decisions between options, humans are expected to choose the option that returns the highest benefit. In practice, however, adding inferior alternatives to the choice set can alter these decisions. Here we investigated whether decisions over the facial features that people find healthy looking can also be affected by the context in which they see those faces. To do this we examined the effect of choice set on the perception of health of images of faces of light-skinned Caucasian females. We manipulated apparent facial health by changing yellowness of the skin: the healthy faces were moderately yellow and the less healthy faces were either much more yellow or much less yellow. In each experiment, two healthy faces were presented along with a third, less healthy face. When the third face was much more yellow, participants chose the more yellow of the two healthy faces more often as the most healthy. However, when the third face was the least yellow, participants chose the less yellow of the two healthy faces more often. A further experiment confirmed that this result is not due to a generalised preference for an intermediate option. These results extend our understanding of context-dependent decision-making in humans, and suggest that comparative evaluation may be a common feature across many different kinds of choices that humans have to make.Peer reviewe

UBV photometry of close visual double stars using an area scanner

A computer-controlled area scanner designed for use on close visual double stars is described. Techniques used in making observations and in subsequent reduction of the data are given. Problems encountered are discussed. Magnitude differences and magnitudes and colours of components are given for 153 bright southern close visual doubles. Separations are given for some of the stars. Absolute magnitudes are calculated for the primaries by several methods. Individual stars are discussed where appropriate. The accuracy of the results is discussed. No significant systematic errors are evident in the results, but systematic errors are present in the results of other authors. Suggestions are made for the future use of conventional photometers, scanners and other techniques in the field of visual double star photometry and astrometry

Along Came a Virus: Leisure in a Dangerous Time Hermeneutic phenomenological explorations of the lifeworld experiences and meanings of leisure of African immigrant mothers and daughters, during the COVID-19 pandemic

The purpose of my hermeneutic phenomenological study was to explore the lived experiences of leisure of African immigrant mothers and daughters resettled in Canada during the COVID-19 pandemic. My research questions explored (a) how African immigrant mothers and daughters describe their lived experiences of leisure (both indoor and outdoor) during the COVID-19 pandemic, (b) the meanings African immigrant mothers and daughters ascribed to their leisure experiences during the COVID-19 pandemic, and (c) their relationships with each other, with friends or other leisure companions, during the COVID-19 pandemic. I conducted my research at a time in the pandemic before COVID-19 vaccines were widely available. Methodologically, my hermeneutic phenomenological study was underpinned by two philosophies: Aristotle’s philosophy of leisure (Hemingway, 1988; Owens, 1981) and Gadamer’s (2004) theory of hermeneutic experience. I engaged in philosophical hermeneutic interviews (Vandermause & Fleming, 2011), augmented by visual methods (Margolis & Zunjarwad, 2018), including drawings and auto-driven photo elicitation (Samuels, 2004), to gather stories of 14 participants’ lived experiences of leisure. Participants comprised four mothers (aged 29-36) and ten daughters (aged 13-24). I analysed the interviews in accordance with Hycner’s (1985) phenomenological interview procedures, combined with those of Finlay (2014) and Brinkmann and Kvale (2015) and turned to theory from fields within and beyond leisure to facilitate the interpretations of the findings. I generated themes from my data as follows: The crucible of cultural hearth, in which I described the experience of loss in terms of severed connections, leisure, and the faith sanctuary. In The cultural hearth warms I explored the ways in which leisure became possible and was often expressed through culture. In the theme My soul soothed in arts- and nature-based leisure I examined how creative leisure and leisure in nature soothed and brought pleasure. In Come together: The worldwide digital hearth I detailed how digital leisure allowed for connection with others, daily living tasks to go on, and became a fount of entertainment. Finally, in The friends at the hearth: Developing and deepening ties I considered the ways in which friendship comforted participants. The pandemic shocked participants as familiar gathering places, such as churches and restaurants, closed. Participants lost jobs and volunteer work. They decried being unable to have leisure, socialize with friends, or travel. Participants attended church services online or found different ways of expressing their faith that brought comfort and succour. Participants found leisure derived from their cultural heritage traditions especially satisfying. Leisure companionship within families strengthened participants’ appreciation for their loved ones and firmed their familial bonds. Family members became close companions; mothers and daughters took renewed interest in each other and sought each other for leisure of many different kinds. Mothers and daughters shared culinary traditions, heritage language learning, and played traditional African games. Embodying the African ethic of ubuntu mothers in healthcare found leisure in extending care and protectiveness to the vulnerable people they served in their work. Surprising friendships blossomed and participants expressed gladness at the unexpected deepening of their relationships with friends. Creative leisure such as painting, writing, dancing, and sewing, were cathartic for expressing political convictions, experiencing nostalgia, and evoking joy and happiness. Connection to the land, and cultivating, harvesting, and consuming plants native to their homelands gave comfort, satisfaction, and purpose to participants’ pandemic leisure. Equally important was digital leisure. The internet not only meant that life could go on: banking, studying, reading electronically, playing games, working from home, it afforded plenty of entertainment too—though it palled with a surfeit of it. Importantly, the pandemic revealed in stark relief, the leisures—and relationships—they had taken for granted that had been sidelined by pandemic health restrictions, and focused participants on what was important in their lives. Given the participants' experiences, they may have benefitted from the expansion of access to nature and community gardening, and the provision of affordable internet access and intuitive, user-friendly technologies to bolster online connectivity and prevent isolation during a crisis. These findings may resonate with other groups under similar social and health restrictions