New Bounds for Edge-Cover by Random Walk

We show that the expected time for a random walk on a (multi-)graph $G$ to traverse all $m$ edges of $G$, and return to its starting point, is at most $2m^2$; if each edge must be traversed in both directions, the bound is $3m^2$. Both bounds are tight and may be applied to graphs with arbitrary edge lengths, with implications for Brownian motion on a finite or infinite network of total edge-length $m$

Why Machiavellianism Matters in Childhood: The Relationship Between Children's Machiavellian Traits and Their Peer Interactions in a Natural Setting

The current study investigated the association between Machiavellianism and children’s peer interactions in the playground using observational methods. Primary school children (N = 34; 17 female), aged 9 to 11 years, completed the Kiddie Mach scale and were observed in natural play during 39 recesses (average observed time = 11.70 hours) over a full school year. Correlations for boys revealed that Machiavellianism was related to more time engaging in direct and indirect aggression, being accepted into other peer groups, and accepting peers into their own social group. Correlations revealed that for girls, Machiavellianism was associated with lower levels of indirect aggression, less time being accepted into other groups and less time accepting and rejecting other children into their own group. This preliminary pilot study indicates that Machiavellianism is associated with children’s observed social behaviour and aims to promote future observational research in this area

Spectral asymptotics of the Laplacian on supercritical bond-percolation graphs

We investigate Laplacians on supercritical bond-percolation graphs with different boundary conditions at cluster borders. The integrated density of states of the Dirichlet Laplacian is found to exhibit a Lifshits tail at the lower spectral edge, while that of the Neumann Laplacian shows a van Hove asymptotics, which results from the percolating cluster. At the upper spectral edge, the behaviour is reversed.Comment: 16 pages, typos corrected, to appear in J. Funct. Ana

Systematic review of interventions for the secondary prevention and treatment of emotional abuse of children by primary carers

Background Emotional abuse (or psychological maltreatment, as it is more commonly called in the US) is an inadequately researched and poorly understood concept, despite increasing awareness about the harm it can cause to children‟s lives. Although it unifies and underpins all types of maltreatment it also occurs alone and when it does, tends to elude detection and intervention. There have to date been no systematic reviews of the literature on the secondary prevention and treatment involving the parents or primary carers of emotionally abused children. Objective The objective of the review was to identify studies that evaluate the effectiveness of interventions in the secondary prevention and treatment of child emotional abuse involving the parents or primary carers of children aged 0 – 19 years. Methods Studies were included if they involved any intervention which was directed at emotionally abusive parenting and that measured change in (i) emotional unavailability (ii) negative attributions (i.e. that involve the parent attributing negative intentions, beliefs or attitudes toward the child); (iii) developmentally inappropriate interactions; (iv) lack of recognition of children‟s boundaries; (v) inconsistency of parenting role; (vi) missocialisation or consistent failure to promote the child‟s social adaptation. The primary outcomes evaluated involved proxy measures of a range of parent, family and child outcomes including parental psychopathology, parenting attitudes and practices, family functioning and/or child behaviour and the child‟s development and adaptation. . A broad search strategy was developed in order to identify as many relevant studies as possible. An electronic search of a wide range of databases was carried about. No study type was excluded. The search was augmented by direct contact with academics and practitioners known in this field. The search included studies written in English, Spanish, French and German. Studies were included if the intervention was described, and the impact on at least one indicator of emotional abuse was assessed. Included studies were critically appraised by two reviewers using standard criteria. Data were extracted using a standard proforma, and a qualitative synthesis of results was carried out. Results The initial search yielded 4248 publications of potential interest. Of these, 175 were obtained for possible inclusion or as background material. A total of 21 studies of 18 interventions, met all the inclusion criteria. A further 43 studies were relevant, but did not meet all of the inclusion criteria. Studies were organised according to the type of emotional abuse targeted: emotionally abusive parenting; parents of infants with faltering growth; missocialisation: parenting interventions with substance-abusing mothers. Twelve included studies had quantitative designs. Of these, 6 comprised randomised controlled trials; 1 comprised a follow-up of a randomised controlled trial; 2 were controlled studies; and 3 had one-group pre- and post-designs. The remaining 9 were case studies. Included studies involved a wide range of interventions. The 8 studies for parents which address emotionally abusive parenting (rejection, misattribution, parent-child role reversal and anger management) involved evaluations of cognitive-behavioural training (CBT), behavioural training and parent-infant psychotherapy. Two further case studies involved cognitive-behavioural training, mentalisation and family-based therapy. The 9 interventions with parents of infants with faltering growth evaluated CBT, behavioural training, parent infant psychotherapy and interaction guidance; lay home visitors, and a range of therapeutic options based on the diagnostic condition of the parents. The 3 studies of interventions for substance abusing mothers evaluated a relational psychotherapy group for mothers, and a residential treatment for substance abuse with a parenting component. The sample sizes for quantitative studies were small and ranged from 17 to 98 participants. Ten interventions involved mothers alone, while a further 11 included fathers, either at the outset or at a later stage, and in 3 cases extended family members. Interventions for emotionally abusing parents The findings from the 8 included studies evaluating CBT, psychotherapy, and behavioural approaches suggest that group-based CBT may be an effective means of intervening with this group of parents, although it cannot currently be recommended with parents experiencing symptoms of severe psychopathology. While one comparative study showed a psychotherapeutic intervention to be more effective than a CBT focused intervention, the outcomes measured in this study (i.e. parent and child representations) favoured the former. Behavioural case work involving the use of problem-solving techniques may also have a role to play with some parents, although further research is still needed. Interventions to enhance parental sensitivity The findings from a systematic review of 81 interventions that aimed at enhancing parental sensitivity and / or infant attachment found strong evidence that short term (less than 16 sessions) interventions, with a behavioural focus and aimed exclusively at enhancing maternal sensitivity were also most effective in enhancing infant attachment security. This supports the notion of a causal role of sensitivity in shaping attachment. Interventions that included fathers as well as mothers showed higher effect sizes but results are tentative since they are based on a small number of small scale trials. Parental behaviours associated with faltering growth Nine studies evaluated a range of interventions with parents of babies with faltering growth including interaction guidance, home visiting; parent-child psychotherapy, behavioural casework and multi-component interventions. The findings show that interaction guidance and parent-infant psychotherapy may be potentially effective means of working with this group of clients along with behavioural casework, but that further research is needed before these can be recommended. Missocialisation: Parenting interventions for substance-abusing parents 5 studies (one of which was a 6-month follow-up) evaluated interventions for substance abusing mothers, including a relational psychotherapy group and a residential treatment for substance abusing adults with a parenting component. The findings show that initial gains made in the former were not sustained at 6-months and few benefits from residential intervention. Conclusions Emotional abuse is a complex issue resulting in part from learned behaviours, psychopathology and/or unmet emotional needs in the parents, and often compounded by factors in the families‟ immediate and wider social environment. As such, a „one-approach-fits-all‟ is unlikely to lead to sustained change. The evidence base is weak, but suggests that some caregivers respond well to cognitive behavioural therapy. However, the characteristics that define these parents are not clear. There is currently no evidence to support the use of this intervention alone in the treatment of severely emotionally abusive parents. Some of the evidence suggests that a certain form of emotional abuse (for example, highly negative parent affect, which may be expressed as frightened and frightening behaviours in the parent) stemming from unresolved trauma and loss, is less amenable to CBT. There is some evidence that interaction guidance and psychotherapeutic approaches can generate change in parents with more severe psychopathology. Further research is urgently needed to evaluate the benefits of both psychotherapeutic and cognitive behavioural interventions, including those which take the form of family therapy, with parents at the more severe end of the spectrum, with fathers, and with older children. There is also a need to gain further understanding about which forms of emotional abuse respond best to different treatments

Mapping lessons from ants to free flight: An ant-based weather aviodance algorithm in free flight airspace

The continuing growth of air traffic worldwide motivates the need for new approaches to air traffic management that are more flexible both in terms of traffic volume and weather. Free Flight is one such approach seriously considered by the aviation community. However the benefits of Free Flight are severely curtailed in the convective weather season when weather is highly active, leading aircrafts to deviate from their optimal trajectories. This paper investigates the use of ant colony optimization in generating optimal weather avoidance trajectories in Free Flight airspace. The problem is motivated by the need to take full advantage of the airspace capacity in a Free Flight environment, while maintaining safe separation between aircrafts and hazardous weather. The experiments described herein were run on a high fidelity Free Flight air traffic simulation system which allows for a variety of constraints on the computed routes and accurate measurement of environments dynamics. This permits us to estimate the desired behavior of an aircraft, including avoidance of changing hazardous weather patterns, turn and curvature constraints, and the horizontal separation standard and required time of arrival at a pre determined point, and to analyze the performance of our algorithm in various weather scenarios. The proposed Ant Colony Optimization based weather avoidance algorithm was able to find optimum weather free routes every time if they exist. In case of highly complex scenarios the algorithm comes out with the route which requires the aircraft to fly through the weather cells with least disturbances. All the solutions generated were within flight parameters and upon integration with the flight management system of the aircraft in a Free Flight air traffic simulator, successfully negotiated the bad weather

The Extreme Hosts of Extreme Supernovae

We use GALEX ultraviolet (UV) and optical integrated photometry of the hosts of 17 luminous supernovae (LSNe, having peak M_V 100 M_☉), by appearing in low-SFR hosts, are potential tests for theories of the initial mass function that limit the maximum mass of a star based on the SFR

Waste in the tropics: Urban environments and (post) colonial infrastructure in Kochi, India

n 2015, the Kochi government—the Cochin Corporation—announced it was planning to replace a controversial landfill on the outskirts of the city with a waste-to-energy incinerator. This incinerator was to stop unscientific landfill practices from leaching into nearby waterways and to solve the issue of plastic waste accumulating in Kochi’s famous backwaters—a series of brackish canals and lakes that the city rests within. These plans coincided with a national agenda of waste reform promoted by the Prime Minister Narendra Modi during his successful election campaign in 2014. However, when I arrived in Kochi in January 2018 the waste-to-energy incinerator was still yet to be installed, caught between a dilapidated landfill, a national policy promoting waste-to-energy infrastructure, and a wet tropical environment that made this infrastructure illogical and unviable. In this thesis I critique the claim to the universality of infrastructures to solve waste management crises and suggest that situated environmental conditions need to be front and centre of discussions about urban governance. Through an ethnographic study of this controversy, I draw on scholarship in environmental anthropology, science and technology studies, and the burgeoning field of discard studies to explain why Kochi continues to attempt to adopt incineration infrastructure to solve a waste crisis despite its ill-suitedness to the tropical conditions of coastal South India. I expand on discussions within these fields by drawing together the (post)colonial history of infrastructure in Kochi and the specific material and capitalist histories of plastics. I also work with the situated concepts of wet and dry—as the categories of both tropical weather and waste systems—to extend ethnographic attention to tropical environments that includes the affective atmospheres and experiences of those environments. I argue that there is a need to expand what is relevant to discussions about urban governance to include specific (post)colonial histories of environmental change, the capitalist and material history of disposable plastics, and the ideological functioning of infrastructure. Part of this reckoning with colonial and material histories requires reimagining relationships between environment and infrastructure. This reimagining involves an unworking of the colonial inheritances of speed and convenience associated with infrastructural development that promotes capitalist growth. Informed by 16 months in India, and 10 months of ethnographic fieldwork in Kochi between January 2018 and April 2019, my observations are drawn primarily from participant observation with waste activists in their advocacy throughout the city. I also draw on over 100 semi-structured interviews with environmental activists, waste workers, architects, academics, politicians, artists, and everyday citizens. Together these methods help to tell the story of a city grappling at once with the toxicity of a plastic waste crisis, the inheritances of large-scale environmental change from British rule in the early 20th century, and decades of postcolonial urban development based on extractive and polluting industries. Ultimately, the thesis provides a timely contribution to the pressing issue of plastic waste management in (post)colonial cities, while also extending recent debates on the intersection of environment and infrastructure.Thesis (Ph.D.) -- University of Adelaide, School of Social Sciences, 202

Distribution of some pectic and arabinogalactan protein epitopes during Solanum lycopersicum (L.) adventitious root development

Background: The adventitious roots (AR) of plants share the same function as primary and lateral roots (LR), although their development is mainly an adaptive reaction to stress conditions. Regeneration of grafted plants is often accompanied by AR formation thus making the grafting technique a good model for studying AR initiation and development and their means of emergence. Pectins and arabinogalactan proteins (AGP) are helpful markers of particular cellular events, such as programmed cell death (PCD), elongation, proliferation or other differentiation events that accompany AR development. However, little is known about the distribution of pectins and AGPs during AR ontogeny, either in the primordium or stem tissues from which AR arise or their correspondence with these events during LR formation. Results: AR were developed from different stem tissues such as parenchyma, xylem rays and the cambium, depending on the stem age and treatment (grafting versus cutting) of the parental tissue. Immunochemical analysis of the presence of pectic (LM8, LM19, LM20) and AGP (JIM8, JIM13, JIM16) epitopes in AR and AR-associated tissues showed differential, tissue-specific distributions of these epitopes. Two pectic epitopes (LM19, LM20) were developmentally regulated and the occurrence of the LM8 xylogalacturonan epitope in the root cap of the AR differed from other species described so far. AGP epitopes were abundantly present in the cytoplasmic compartments (mainly the tonoplast) and were correlated with the degree of cell vacuolisation. JIM8 and JIM13 epitopes were detected in the more advanced stages of primordium development, whereas the JIM16 epitope was present from the earliest division events of the initial AR cells. The comparison between AR and LR showed quantitative (AGP,) and qualitative (pectins) differences. Conclusion: The chemical compositions of adventitious and lateral root cells show differences that correlate with the different origins of these cells. In AR, developmental changes in the distribution of pectins and AGP suggest the turnover of wall compounds. Our data extend the knowledge about the distribution of pectin and AGP during non-embryogenic root development in a species that is important from an agronomic point of view

Trust, inflammatory biomarkers and adversity: a novel investigation and clinical implications

Survivors of adversity and trauma experience high levels of distress, interpersonal challenges and poor physical health. We investigated the role of trust in trauma-related psychological and physiological responses. Serum concentrations of C-reactive protein, cortisol, tumour necrosis factor-alpha and interleukin-8 from 25 participants in Scotland were measured. Trauma history and experience were assessed using the Childhood Trauma Questionnaire and Life Events Checklist. Trauma symptomatology was measured by the Impact of Event Scale. Interpersonal trust was measured using the Trust Scale. Trauma history and inflammatory biomarker concentrations were significant predictors of trauma symptomatology with trust as a covariate. Psychological and physiological responses after trauma seem strongly linked. Trust can mediate distress and physiology in adversity