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Abstract  

Bench scale experiments were conducted to determine the dissolution characteristics of UO2, U3O8, and UO3 in aqueous peroxide-containing carbonate solutions. The experimental parameters investigated included carbonate countercation (NH4 +, Na+, K+, and Rb+) and H2O2 concentration. The carbonate countercation had a dramatic influence on the dissolution behavior of UO2 in 1 M carbonate solutions containing 0.1 M H2O2, with the most rapid dissolution occurring in (NH4)2CO3 solution. The initial dissolution rate (y) of UO2 in 1 M (NH4)2CO3 increased linearly with peroxide concentration (x) ranging from 0.05 to 2 M according to: y = 2.41x + 1.14. The trend in initial dissolution rates for the three U oxides under study was UO3 ≫ U3O8 > UO2.

Restricted access
European Journal of Microbiology and Immunology
Authors:
Sai Duraisingham
,
Steven Hanson
,
Matthew Buckland
,
Sofia Grigoriadou
, and
Hilary Longhurst

Pseudomonas aeruginosa (PA) is commonly isolated from the respiratory secretions of antibody deficiency patients, but the significance of this has not been well studied. We have reviewed our adult antibody deficiency cohort of 179 patients and assessed the prevalence and characteristics of PA infection and the effects of early antibiotic eradication treatments. Of the 34 patients with PA, 55.9% (19) underwent successful eradication and were infection-free, 38.2% (13) had intermittent infection, and 5.9% (2) had chronic PA. PA infection was significantly associated with bronchiectasis (p < 0.0001), with 36.1% (22 out of 61) of patients with bronchiectasis developing a PA infection. Infection status was also significantly associated with chronic sinusitis (p < 0.0001). Most treated PA exacerbations were symptomatic and with colony counts of ≥1000 cfu/ml. Current eradication protocols used at our center involve early treatment at first positive isolate with ciprofloxacin for 3 weeks and nebulized colomycin for 3 months, and if eradication fails, intravenous ceftazidime and gentamycin or colomycin is administered for 2 weeks. Continued sputum surveillance and early eradication treatments upon positive PA culture may help to limit chronic PA infection in antibody deficiency patients.

Open access
Journal of Behavioral Addictions
Authors:
Matthew Browne
,
Paul Delfabbro
,
Hannah B. Thorne
,
Catherine Tulloch
,
Matthew J. Rockloff
,
Nerilee Hing
,
Nicki A Dowling
, and
Matthew Stevens

Abstract

Background and aims

It is well understood that engagement with some forms of gambling, like EGMs, is riskier than other forms. However, while reports of associations are common, few studies have attempted to evaluate and compare the relative risk of all available forms, and none have estimated the relative contribution of each form to the total burden of gambling problems (GP) in a population.

Methods

Using an aggregated dataset of national and state-based prevalence studies in Australia (N = 71,103), we estimated prevalence and unique effects of frequency of engagement on each form on GP. Two alternative numerical methods were then applied to infer the relative contribution of each form to the total amount of GP.

Results

EGMs are responsible for 51%–57% of gambling problems in Australia, and 90% of gambling problems are attributable to EGMs, casino, race, and sports betting. Casino table games and EGMs are equally risky at the individual level, but the former contribute far less to problems due to low participation. Bingo and lottery play show no statistically detectable risk for GP.

Discussion and conclusion

The results illustrate which forms present the greatest population burden and illuminate the reasons why. EGMs have an outsized impact. EGM uniquely combines high risk conditional on play, with a high participation rate and a high frequency of play among participants. This is in contrast to risky but less commonly played casino games, and prevalent but non-risky forms like lotteries. We conclude that EGM regulation should be a primary focus of policy action in Australia. More innovative policy ideas relating to EGMs should be tested due to the disproportionate impact of this product type.

Open access
Journal of Behavioral Addictions
Authors:
Alex M.T. Russell
,
Matthew Browne
,
Nerilee Hing
,
Matthew Rockloff
,
Philip Newall
,
Nicki A. Dowling
,
Stephanie Merkouris
,
Daniel L. King
,
Matthew Stevens
,
Anne H. Salonen
,
Helen Breen
,
Nancy Greer
,
Hannah B. Thorne
,
Tess Visintin
,
Vijay Rawat
, and
Linda Woo

Abstract

Background

Electronic gaming machines (EGMs) are one of the most harmful forms of gambling at an individual level. It is unclear whether restriction of EGM functions and accessibility results in meaningful reductions in population-level gambling harm.

Methods

A natural policy experiment using a large (N = 15,000) national dataset weighted to standard population variables was employed to compare estimates of gambling problems between Australian residents in Western Australia (WA), where EGMs are restricted to one venue and have different structural features, to residents in other Australian jurisdictions where EGMs are widely accessible in casinos, hotels and clubs. Accessibility of other gambling forms is similar across jurisdictions.

Results

Gambling participation was higher in WA, but EGM participation was approximately half that of the rest of Australia. Aggregate gambling problems and harm were about one-third lower in WA, and self-reported attribution of harm from EGMs by gamblers and affected others was 2.7× and 4× lower, respectively. Mediation analyses found that less frequent EGM use in WA accounted for the vast majority of the discrepancy in gambling problems (indirect path = −0.055, 95% CI −0.071; −0.038). Moderation analyses found that EGMs are the form most strongly associated with problems, and the strength of this relationship did not differ significantly across jurisdictions.

Discussion

Lower harm from gambling in WA is attributable to restricted accessibility of EGMs, rather than different structural features. There appears to be little transfer of problems to other gambling forms. These results suggest that restricting the accessibility of EGMs substantially reduces gambling harm.

Open access
Journal of Behavioral Addictions
Authors:
Nerilee Hing
,
Alex M. T. Russell
,
Matthew Browne
,
Matthew Rockloff
,
Catherine Tulloch
,
Vijay Rawat
,
Nancy Greer
,
Nicki A. Dowling
,
Stephanie S. Merkouris
,
Daniel L. King
,
Matthew Stevens
,
Anne H. Salonen
,
Helen Breen
, and
Linda Woo

Abstract

Background and aims

Gambling-related harm to concerned significant others (CSOs) is an important public health issue since it reduces CSOs' health and wellbeing in numerous life domains. This study aimed to 1) estimate the first national prevalence of CSOs harmed by gambling in Australia; 2) identify the characteristics of CSOs most at risk of harm from another person's gambling; 3) compare the types and number of harms experienced by CSOs based on their relationship to the person who gambles; and 4) compare the number of harms experienced by CSOs by self-identified gender.

Methods

Based on a national CATI survey weighted to population norms, 11,560 respondents reported whether they had been personally and negatively affected by another person's gambling in the past 12 months; and if so, answered detailed questions about the harms experienced from the person's gambling who had harmed them the most.

Results

Past-year prevalence of gambling-related harm to adult Australian CSOs was (6.0%; 95% CI 5.6%–6.5%). CSOs most commonly reported emotional harms, followed by relationship, financial, health and vocational harms, respectively. Former partners reported the most harm, followed by current partners, other family members and non-family members, respectively. Female CSOs were more likely to report more harm and being harmed by a partner or other family member, and male CSOs from a non-family member.

Discussion and conclusions

The findings provide new insights into the wider societal burden of gambling and inform measures aimed at reducing harm to CSOs from gambling and supporting them to seek help.

Open access
Journal of Behavioral Addictions
Authors:
Nerilee Hing
,
Alex M.T. Russell
,
Vijay Rawat
,
Gabrielle M. Bryden
,
Matthew Browne
,
Matthew Rockloff
,
Hannah B. Thorne
,
Philip Newall
,
Nicki A. Dowling
,
Stephanie S. Merkouris
, and
Matthew Stevens

Abstract

Background and aims

COVID-19 lockdowns limited access to gambling but simultaneously elevated psychosocial stressors. This study assessed the relative effects of these changes on gambling risk status during and after the Australian COVID-19 lockdown from late-March to late-May 2020.

Methods

The study administered three surveys to people who had gambled within the past year at T1. Wave 1 asked about before (T1, N = 2,125) and during lockdown (T2, N = 2,125). Subsequent surveys focused on one year (T3; N = 649) and two years after lockdown (T4, N = 458). The dependent variable was changes in reporting any problem gambling symptoms (PGSI 0 vs 1+). Bivariate analyses and multinomial logistic regression tested for significant associations with: demographics, psychosocial stressors (perceived stress, psychological distress, loneliness, health anxiety about COVID, financial hardship, stressful life events), gambling participation and gambling frequency.

Results

Gambling participation and at-risk gambling decreased between T1 and T2, increased at T3, with little further change at T4. When gambling availability was curtailed, decreased gambling frequency on EGMs, casino games, sports betting or race betting, and lower psychosocial stress, were associated with transitions from at-risk to non-problem gambling. When gambling availability resumed, increased EGM gambling frequency, decreased online gambling frequency, and higher psychosocial stress were associated with transitions from non-problem to at-risk gambling.

Discussion and conclusions

Gambling availability appears a stronger influence on gambling problems, at the population level, than psychosocial risk factors. Reducing the supply of high-risk gambling products, particularly EGMs, is likely to reduce gambling harm.

Open access