On properties of Karlsson Hadamards and sets of Mutually Unbiased Bases in dimension six

The complete classification of all 6x6 complex Hadamard matrices is an open problem. The 3-parameter Karlsson family encapsulates all Hadamards that have been parametrised explicitly. We prove that such matrices satisfy a non-trivial constraint conjectured to hold for (almost) all 6x6 Hadamard matrices. Our result imposes additional conditions in the linear programming approach to the mutually unbiased bases problem recently proposed by Matolcsi et al. Unfortunately running the linear programs we were unable to conclude that a complete set of mutually unbiased bases cannot be constructed from Karlsson Hadamards alone.Comment: As published versio

Holocene Environmental Change in Mainland Southeast Asia: Pollen and Charcoal Records From Cambodia.

Major Holocene environmental changes in continental Southeast Asia are reconstructed using proxy data derived from analysis of 14C-dated changes in pollen, microscopic charcoal, and organic/inorganic carbon in sediment cores taken from permanent, closed-basin, volcanic lakes in Ratanakiri Province, northeastern Cambodia. Analysis focuses on the history of monsoon climate and land use, inferred from changes in vegetation, fire regime, and lake conditions. These data provide the first well dated palynological record, covering most of the Holocene and continuous up to the present, from an upland site in mainland Southeast Asia. The record from a 15-meter core retrieved from Yeak Kara Lake, representing the last 9300 years, shows that the Late Glacial period ended about 8500 BP, more than 1000 years later than sites in southwest China. Maximum summer monsoon intensity occurred ca. 8000--5400 BP, similar to most other sites in the Asian monsoon region. A subsequent increase in burning caused expansion of secondary forests at the expense of dense semi-evergreen forests. After ca. 3500 BP fire frequency may have increased further, leading to expansion of dry deciduous forests. From ca. 2500 BP up to the present, dense forest has recovered in a mosaic with annually-burned dry forest, due either to a Late Holocene strengthening of the monsoon or to more pervasive control of the fire regime by indigenous populations. The pattern of burning for the last 2500 years, corroborated by charcoal records from two other nearby lakes, shows lowest burning intensity perhaps coinciding with the development and demise of major civilizations (Funan, Chenla, Angkor) in the region

Bio-Inspired Information Extraction In 3-D Environments Using Wide-Field Integration Of Optic Flow

A control theoretic framework is introduced to analyze an information extraction approach from patterns of optic flow based on analogues to wide-field motion-sensitive interneurons in the insect visuomotor system. An algebraic model of optic flow is developed, based on a parameterization of simple 3-D environments. It is shown that estimates of proximity and speed, relative to these environments, can be extracted using weighted summations of the instantaneous patterns of optic flow. Small perturbation techniques are utilized to link weighting patterns to outputs, which are applied as feedback to facilitate stability augmentation and perform local obstacle avoidance and terrain following. Weighting patterns that provide direct linear mappings between the sensor array and actuator commands can be derived by casting the problem as a combined static state estimation and linear feedback control problem. Additive noise and environment uncertainties are incorporated into an offline procedure for determination of optimal weighting patterns. Several applications of the method are provided, with differing spatial measurement domains. Non-linear stability analysis and experimental demonstration is presented for a wheeled robot measuring optic flow in a planar ring. Local stability analysis and simulation is used to show robustness over a range of urban-like environments for a fixed-wing UAV measuring in orthogonal rings and a micro helicopter measuring over the full spherical viewing arena. Finally, the framework is used to analyze insect tangential cells with respect to the information they encode and to demonstrate how cell outputs can be appropriately amplified and combined to generate motor commands to achieve reflexive navigation behavior

Multidisciplinary Viewpoints on Global River Systems

In January 2014, 27 scholars from across the disciplines met at Indiana University Purdue University Indianapolis for the Rivers of the Anthropocene conference to present their research on global river systems. While they were here, we interviewed eleven of them about the methodological and conceptual challenges of transdisciplinary approaches to environmental research. In our paper, we synthesize those interviews into an accessible report detailing the presenters’ responses. The sources of information that we use are the interviews themselves, which we cross-reference with the recorded presentations from the Rivers conference, as well as published work on transdisciplinarity. This research is important because it shows how studying the effects humans have had on global river systems from a multidisciplinary angle gives us, as a society, a better idea of how to address the problems caused by human alterations to the natural environment

Supporting and inhibiting the well-being of early career secondary school teachers: extending self-determination theory

This article reports an original examination of the well-being of early career secondary school teachers in England, which extends the evidence bases relating to early career teachers’ working lives, teacher well-being, self-determination theory (Ryan & Deci, 2000), and performativity (Ball, 2003), respectively. Drawing on a secondary analysis of qualitative data generated for four separate empirical studies between 2005 and 2013, in a context in which teachers’ work was subject to unparalleled external regulation, the authors examine the extent to which the well-being of early career teachers can be explained by self-determination theory, which posits that well-being is enhanced when innate psychological needs for competence, relatedness and autonomy are satisfied. The findings suggest that satisfaction of these three basic psychological needs is a necessary but not sufficient condition for optimising the well-being of early career teachers, which is dependent upon the interaction of a wider range of individual, relational and micro-, meso- and macro-environmental factors. Amongst the recommendations for policy and practice, policymakers and school leaders are urged to uphold their duty of care to newly and recently qualified teachers by doing their utmost to create conditions for the optimisation of their well-being. Several specific means of bringing this about are proposed, together with a checklist for those concerned to support early career teachers’ well-being. Keywords: teacher well-being; early career teachers; self-determination theory; performativit

Case Study: Effects of COVID-19 on a Mid-Size San Francisco Commercial General Construction Company

The Covid-19 pandemic has had an adverse effect on the commercial construction industry. New safety procedures and regulations set by local government and health officials have made it difficult for construction to proceed at the efficiency level it had prior to the pandemic. The San Francisco Bay Area was subject to strict protocols starting in March of 2020 that vastly limited the capability of construction companies to perform work. This case study looks into the ways in which a mid sized commercial general construction contractor from the San Francisco Bay Area was impacted by Covid-19 and the methods they used to handle the associated challenges. While initially being closed completely from a statewide shelter in place order, the company eventually was permitted to return to work, and was tasked with developing ways to mitigate the transmission of the virus on their job sites to keep employees safe and projects open. Additionally, the company had to make adjustments from a business standpoint to keep itself profitable in the present and the future. The company’s position in a region heavily impacted by the Covid-19 Pandemic makes them a good candidate for conducting a study in this area

Understanding the needs of vulnerable prisoners: the role of social and emotional wellbeing

Purpose: Social and emotional wellbeing (SEWB) is a term used to refer to the state of an individual's overall wellbeing. This review aims to consider the importance of understanding and assessing SEWB in prisoner populations, and identify potentially important differences between groups of prisoners, including those who identify as from minority cultural backgrounds (Aboriginal and Torres Strait Islander in Australia), protective custody prisoners, remand prisoners, prisoners identified with an intellectual disability, and prisoners with an acquired brain injury. Design/methodology/approach: The paper is a general review of the published literature, with a specific focus on work conducted with Aboriginal and Torres Strait Islander communities in Australia. Findings: Eight domains of SEWB are identified across which Aboriginal and Torres Strait Islander prisoners, along with those in protection units, remandees, and prisoners with intellectual disabilities or acquired brain injuries are likely to experience particularly low levels of functioning. Few programs have been developed to address these needs, although attending to low levels of SEWB has the potential to make a positive contribution to prisoner health, prison management, and offender rehabilitation. Originality/value: Relatively little literature has considered this topic previously and, as a result, the paper is necessarily descriptive. Nonetheless, issues of SEWB appear to warrant further consideration, particularly in relation to those prisoners who identify with minority cultural groups

The survival of witchcraft prosecutions and witch belief in South West Scotland

During the era of the Scottish witch-hunts, Dumfries and Galloway was one of the last regions to initiate witch prosecutions, but it was also one of the most reluctant to completely surrender all belief in witches until a comparatively late date. In the late seventeeth and early eighteenth centuries south-west Scotland, better known for the persecution of covenanters, took the practice of witchcraft and charming very seriously indeed, and for perhaps longer than other parts of Scotland, though the area has received surprisingly little scholarly investigation. The trial evidence is not incompatible with that found elsewhere though there is less demonic content. Accusations of witchcraft in this region were mostly concerned with the troubles of everyday life, agricultural problems, family tensions and disagreements between neighbours. From 1670 to about 1740, the very decades that were giving birth to the Scottish Enlightenment, learned interest in the supernatural was actually on the increase and the topic received an unprecedented level of questioning, investigation, and scrutiny. Ironically, the ‘superstitions’ that both church and state had been attempting to eradicate for some two hundred years were now being used to defend religion against the growing threat of atheism. The zeal of the ministers does seem to have contributed to the endurance of witch beliefs in the South West, as elsewhere. Against this backdrop, the survival of witch belief and the continued prosecution of witches in southwest Scotland is examined, thus contributing to our understanding of the individualistic nature of witch persecution and the various dynamics at play within the Scottish witch-hunting experience