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Quambalaria shoot blight resistance in marri (Corymbia calophylla): Genetic parameters and correlations between growth rate and blight resistance
No full textQuambalaria shoot blight (QSB) has emerged recently as a severe disease of Corymbia calophylla (marri). In this study, QSB damage and growth were assessed in Corymbia calophylla trees at 4 and 6 years of age in two common gardens consisting of 165 and 170 open-pollinated families representing 18 provenances across the species’ natural distribution. There were significant differences between provenances for all traits. The narrow-sense heritability for growth traits and QSB damage at both sites were low to moderate. The genetic correlation between QSB damage and growth traits was negative; fast-growing families were less damaged by QSB disease. Age-age genetic correlations for individual traits at four and six years were very strong, and the type-B (site–site) correlations were strongly positive for all traits. Provenances from cooler wetter regions showed higher resistance to QSB. The QSB incidence at 6 years was significantly correlated with environmental factors of the provenance’s origin. The QSB incidence at years four and six was not correlated with the QSB expression in 3-month-old seedlings. Based on these results, selection for resistance could be undertaken using 4-year-old trees. There is potential for a resistance breeding program to develop populations of marri genetically diverse and resistant to QSB
International human rights law – lessons in the era of COVID-19
No full textThe COVID-19 pandemic has brought the connections between law and public health into stark relief. The pandemic has demonstrated both the essential nature of global cooperation and international regulation to promote universal rights to life and health, and the potentially harmful impacts of limitations imposed on human rights in time of emergency. It has also tested the international human rights framework, which allows for permissible limitations on human rights where required, but which remains subject to widely varying domestic implementation. In this paper, we explore the relationship between international human rights law and the COVID-19 pandemic, including a focus on the rights of vulnerable individuals and communities who have experienced disproportionate impacts from both the pandemic itself and from measures that constrain the exercise of human rights. We propose that the inquiry and monitoring mechanisms of the UN human rights bodies provide important avenues for addressing the human rights implications of COVID-19 and Government responses to the pandemic. We also review Australia’s domestic implementation of international human rights law and its relevance in the era of COVID-19, noting the piecemeal approach to human rights protection under Australian law. We conclude that this time of emergency provides an opportunity for the progressive development of international human rights law, via principles of reciprocity, social protection, human rights preparedness and comprehensive normative protection for a right to public health
Addition of iron to agricultural topsoil and subsoil is not an effective C sequestration strategy
No full textThe interaction of soil organic matter (SOM) with Fe-containing minerals represents a key mechanism that promotes carbon (C) stabilisation in soil. The addition of Fe-rich industrial by-products to soil may therefore help accelerate C storage. Our understanding of the effects of exogenous Fe addition (Fe (oxy)hydroxide vs. Fe chloride) on SOM dynamics and C dynamics in agricultural soils, especially in subsoils, however, remains poor. Here, we simulate the addition of Fe in an arable soil context and assess its effectiveness based on CO2 emissions and soil chemistry. We hypothesised that insoluble and soluble Fe would reduce the mineralization of newly added unprotected organic materials more than native SOM and that soluble Fe would cause mineralisation of native SOM. To investigate this, insoluble Fe(OH)3 or soluble FeCl2 (0–5 g kg−1) were added to arable top- (0–10 cm) or subsoils (50–60 cm) and CO2 emissions, pH and nutrient dynamics (e.g. P, N) measured in a laboratory incubation over a 45 d period. We also compared the effect of Fe on the turnover of native SOM and newly added C (i.e. 14C-labelled glucose, citrate and crop residues) which was pre-mixed with exogenous Fe. We found that: (1) despite a reduction in P and DOC, Fe(OH)3 did not suppress total CO2 efflux; (2) high FeCl2 rates induced a rapid and significant release of CO2, which we attribute almost entirely to FeCl2-induced soil acidification increasing DOC availability and carbonate dissolution; (3) 14C-substrate mineralisation was weakly suppressed by Fe(OH)3 but strongly by FeCl2 following the series: citrate < glucose < crop residues; and (4) Fe addition to subsoils induced a stronger C mineralisation response but weaker effect on soil solution chemistry compared to topsoil, possibly due to subsoils having a lower buffering ability and less microbial biomass. We conclude that addition of extra Fe was not effective in promoting greater C sequestration in the arable soil we tested
A global analysis of the break-even prices to reduce atmospheric carbon dioxide via forest plantation and avoided deforestation
Get PDFA cross-country assessment of the cost of carbon sequestration in the forest sector is needed for planning and achieving climate commitments, such as the Paris Agreement, at global, regional, national, or sectoral scales. We provide a global and bottom-up assessment of the break-even carbon price to undertake forest plantation and forest conservation at a country level for 166 nations. We construct a global dataset of key cost factors, examine their global distributions, and undertake a cross-country assessment of cost differences with alternative forest programs (plantation and conservation). Our bottom-up approach is also calibrated to sub-national case studies to investigate the average cost of forest carbon in Australian states and Canadian provinces. We find that the break-even carbon price varies by countries, locations within a country, forest programs and co-benefits. Our estimates provide an approximation of the cost-effectiveness of forest carbon sequestration relative to non-forest climate mitigation approaches
Antimicrobial-resistant Bacteroides fragilis in Thailand and their inhibitory effect in vitro on the growth of Clostridioides difficile
No full textObjectives
The aim of this study was to investigate antimicrobial-resistant Bacteroides fragilis in Thailand and possible effects of such strains on human health and disease.
Methods
Phenotypic antimicrobial susceptibility testing was performed on 17 clinical B. fragilis isolates. The genome of one isolate was sequenced and analysed to explore its resistance genotype. An in vitro growth assay was conducted to evaluate the inhibitory effect of B. fragilis on Clostridioides difficile.
Results
There was a high prevalence of clindamycin (71%), meropenem (47%) and moxifloxacin (29%) resistance. Most strains remained susceptible to metronidazole, but one had high-level metronidazole resistance conferred by a nimD-containing plasmid. B. fragilis displayed an in vitro inhibitory effect on the growth of C. difficile and a drug-resistant strain retained this inhibition in the presence of clindamycin.
Conclusions
Antimicrobial resistance was seen in Thai B. fragils isolates, which may help protect the host against C. difficile infection
Why is alexithymia a risk factor for affective disorder symptoms? The role of emotion regulation
No full textBackground
Ever since alexithymia was defined in the 1970s, robust associations have been observed between alexithymia and a variety of symptoms of psychopathology. Alexithymia is now widely regarded as an important transdiagnostic risk factor, and it is frequently assessed in clinical and research settings. However, despite this strong interest, it remains unclear exactly why (i.e., by which mechanisms) alexithymia is linked to psychopathology. In this paper, we hypothesise that alexithymia is linked to affective disorder symptoms because alexithymia impairs people's ability to regulate their emotions, and we empirically test this hypothesis.
Method
We administered a battery of psychometric measures to 501 adults in the United States, and examined the direct and indirect effects between alexithymia (Perth Alexithymia Questionnaire), emotion regulation ability (Perth Emotion Regulation Competency Inventory), and affective disorder symptoms (Depression Anxiety Stress Scales-21).
Results
In the Pearson bivariate correlation matrix, alexithymia, emotion regulation difficulties, and affective disorder symptoms were all significantly correlated. In the modelling of direct and indirect effects, alexithymia was indirectly associated with affective disorder symptoms through emotion regulation difficulties (no significant direct effect).
Limitations
Our online survey data were all self-report data and cross-sectional. Future longitudinal work would be beneficial.
Conclusions
Our findings support contemporary theorising that alexithymia is linked to affective disorder symptoms via emotion regulation difficulties. These results help to clarify the mechanisms by which alexithymia may predispose people to affective disorder symptoms, and highlight the importance of considering the roles of alexithymia and emotion regulation in case conceptualisations and treatment planning
Vegetation structure and fuel dynamics in fire-prone, Mediterranean-type Banksia woodlands
No full textIncreasing extreme wildfire occurrence globally is boosting demand to understand the fuel dynamics and fire risk of fire-prone areas. This is particularly pressing in fire-prone, Mediterranean climate-type vegetation, such as the Banksia woodlands surrounding metropolitan Perth, southwestern Australia. Despite an extensive wildland-urban interface and frequent fire occurrence, fuel accumulation and the spatial variation in fuel risk is not well quantified across the broad extent of this ecosystem. Using a space for time sampling approach to generate a chronosequence of time since fire, we selected sites that spanned across two distinct sandy soil types (Spearwood and Bassendean sands) and a rainfall gradient (550 to 750 mm north–south). We examined 82 sites in Banksia woodlands, southwestern Australia. Of the 82 sites, 44 burnt during the measurement period (2016 to 2021), which provided the opportunity for fuel measurements following fire (resulting in total N = 126). We wanted to answer two key questions: 1) How do measures of fuel load (mass) and arrangement (structure and continuity) vary across space and time, particularly with respect to time since the last fire? 2) How do biophysical drivers, such as soil type and rainfall, influence fuel accumulation and arrangement, and do these covariates improve litter fuel modelling beyond traditional asymptotic models? We found that fine surface fuel loads (litter and small twigs) differed between sand types, accumulating faster and reaching a higher peak on Spearwood sands (7–9 Mg ha−1) compared to Bassendean sands (6–7 Mg ha−1). Shrub layer fuel loads also accumulated faster on Spearwood sands than on Bassendean sands. While shrub layer fuels on Spearwood sands peaked at 14 years and declined thereafter, those on Bassendean sand did not decline over time but have lower overall connectivity. Total fine fuels (fine surface plus fine shrub layer fuels) had no significant decline over the same time period, on either sand type. Total fine fuel loads reached a peak of 9–10 Mg ha−1 between 13- and 20-years following fire, depending on the underlying sand type. Our quantitative fuel accumulation models confirmed the strength of time since fire as a predictor of hazard, but nonetheless included up to 40% unexplained variance. Importantly, while components fluctuated over time, the combined total of fine fuels did not decline with the long absence of fire, suggesting fire risk does not necessarily decrease in long unburned vegetation
Exploring the mental health of circus artists: Circus factors, psychological resilience, and demographics predict disordered eating and exercise addictions
No full textThere are similarities in the performance demands of circus and other performance domains such as leanness sports and dance, yet little is known about the mental health of circus artists. We explored self-reported disordered eating and exercise addictions in a sample of 500 circus artists. The sample consisted of aerial acrobats (71%), floor acrobats (13%), object manipulators (9%), and equilibrists (6%) who participate in circus at a range of performance levels (amateur 50%, part/full-time professional 41%, student 6%, retired 3%). Similar to elite athletes in leanness sports, approximately 36% of the circus artists in our sample were classified as ‘at risk’ of an eating disorder. A binomial logistic regression model suggested that being ‘at risk’ of an eating disorder was negatively related to participants’ age and trait resilience, positively related to exercise addictions, and differences among circus categories were found (i.e., higher among equilibrium and aerial acrobatics). Using a Bayesian estimation procedure, a linear regression model suggested that exercise addiction scores were positively related to participants’ weekly training time and being ‘at risk’ for an eating disorder, negatively associated with their years of experience in circus, and differences between circus categories (high levels in equilibrium) and modality of engagement in circus (higher levels among amateurs) were identified. Consequently, these exploratory study findings indicate that a complex interaction of factors might impact the development of disordered eating and exercise addictions among circus artists. Implications for discipline-specific and experience-specific interventions to address these maladaptive behaviours are discussed
Entitlement mediates the relationship between dark triad traits and academic misconduct
No full textThe Dark Triad personality traits of psychopathy, Machiavellianism, and narcissism are positively related to engagement in academic misconduct (e.g., plagiarism and cheating) by higher education students. This study examined whether feelings of entitlement in an academic context mediated the relationship between Dark Triad personality traits and academic misconduct. Students from three universities (N = 387) completed measures of the Dark Triad, academic entitlement (entitled expectations and externalized responsibilities), and academic misconduct behaviors. One of the two facets of academic entitlement, externalized responsibilities, mediated the relationship between all three dark triad traits and academic misconduct. These results suggest that academic misconduct may be reduced by modifying academic entitlement beliefs among students
Balancing the Equation: A Natural History of Trimethylamine and Trimethylamine-N-oxide
Get PDFTrimethylamine (TMA) and its N-oxide (TMAO) are ubiquitous in prokaryote and eukaryote organisms as well as in the environment, reflecting their fundamental importance in evolutionary biology, and their diverse biochemical functions. Both metabolites have multiple biological roles including cell-signaling. Much attention has focused on the significance of serum and urinary TMAO in cardiovascular disease risk, yet this is only one of the many facets of a deeper TMA–TMAO partnership that reflects the significance of these metabolites in multiple biological processes spanning animals, plants, bacteria, and fungi. We report on analytical methods for measuring TMA and TMAO and attempt to critically synthesize and map the global functions of TMA and TMAO in a systems biology framework