Herbicide impacts on exotic grasses and a population of the critically endangered herb "Calystegia affinis" (Convolvulaceae) on Lord Howe Island

Introduced perennial grasses are capable of altering the habitat of native species, causing reductions in population size and vigour, and potentially affecting life-history processes such as survival, pollination and seedling recruitment. We examined the utility of herbicide treatment on two exotic grasses, Pennisetum clandestinum (Kikuyu) and Stenotaphrum secundatum (Buffalo grass) to restore the habitat of Calystegia affinis, a critically endangered species endemic to Lord Howe and Norfolk Islands. Using two herbicides, Asset (designed to affect only grasses) and Glyphosate (a general herbicide), we compared effectiveness in reducing grass cover on a population of Calystegia affinis. We protected Calystegia plants from the herbicides by ensuring their leaves were covered by plastic bags during herbicide application. Both herbicides were similarly effective in reducing grass cover after four weeks and had no noticeable adverse affect on Calystegia (suggesting the plastic bag protection was effective). After 26 weeks, Glyphosate was more effective in maintaining a reduced grass cover. Plots treated with either herbicide had a greater relative increase in abundance of Calystegia stems compared to untreated controls. The Glyphosate treatment resulted in the greatest relative increase in stem abundance, but this was not significantly greater than in the Asset treatment. We consider that spraying with Glyphosate treatment, with follow-up monitoring and spot-spraying, will assist the recovery of the Calystegia affinis population. Ultimately, the maintenance of a weed-free zone at the forest edge will provide suitable habitat for additional recruitment of this and other native species

Building young children’s emotional competence and self- regulation from birth : the begin to... ECSEL approach

Neuroscientific advances and child development studies show 0-6 years represents a sensitive period for the development of emotional competence—the ability to identify, understand, express and regulate emotion, all foundational to self-regulation. Research suggests optimum teaching of emotional competence and self-regulation skills from birth is through interventions emphasizing co-regulation. This study aimed to examine begin to...ECSEL, an emotional cognitive and social early learning approach that promotes emotional competence and self-regulation by teaching emotion knowledge and emotion regulation through causal talk and causal talk in the emotional experience. The study collected data over three years from 100 students, aged 2-6, receiving begin to...ECSEL. Study goals were to: (1) examine growth over one academic year among students receiving begin to...ECSEL on measures of attachment/relationship, initiative, self- regulation, emotion knowledge, emotion regulation, and related constructs involving empathy, prosocial skills, positive reactions to frustration, negative emotions and aggressive behaviours; (2) examine differences between these students and national normative samples on measures of attachment/relationship, initiative, and self- regulation; and (3) explore differences between these students and normative samples on all the aforementioned constructs. Results demonstrated students significantly improved over time in these constructs and outperformed normative samples on emotionally regulated/prosocial skills, empathy, self-regulation, attachment and initiative.peer-reviewe

BIOGEOCHEMICAL GRADIENTS AS A FRAMEWORK FOR UNDERSTANDING WASTE SITE EVOLUTION

The migration of biogeochemical gradients is a useful framework for understanding the evolution of biogeochemical conditions in groundwater at waste sites contaminated with metals and radionuclides. This understanding is critical to selecting sustainable remedies and evaluating sites for monitored natural attenuation, because most attenuation mechanisms are sensitive to geochemical conditions such as pH and redox potential. Knowledge of how gradients in these parameters evolve provides insights into the behavior of contaminants with time and guides characterization, remedy selection, and monitoring efforts. An example is a seepage basin site at the Savannah River Site in South Carolina where low-level acidic waste has seeped into groundwater. The remediation of this site relies, in part, on restoring the natural pH of the aquifer by injecting alkaline solutions. The remediation will continue until the pH up-flow of the treatment zone increases to an acceptable value. The time required to achieve this objective depends on the time it takes the trailing pH gradient, the gradient separating the plume from influxing natural groundwater, to reach the treatment zone. Predictions of this length of time will strongly influence long-term remedial decisions

THE SCENARIOS APPROACH TO ATTENUATION-BASED REMEDIES FOR INORGANIC AND RADIONUCLIDE CONTAMINANTS

Guidance materials based on use of conceptual model scenarios were developed to assist evaluation and implementation of attenuation-based remedies for groundwater and vadose zones contaminated with inorganic and radionuclide contaminants. The Scenarios approach is intended to complement the comprehensive information provided in the US EPA's Technical Protocol for Monitored Natural Attenuation (MNA) of Inorganic Contaminants by providing additional information on site conceptual models and extending the evaluation to consideration of Enhanced Attenuation approaches. The conceptual models incorporate the notion of reactive facies, defined as units with hydrogeochemical properties that are different from surrounding units and that react with contaminants in distinct ways. The conceptual models also incorporate consideration of biogeochemical gradients, defined as boundaries between different geochemical conditions that have been induced by waste disposal or other natural phenomena. Gradients can change over time when geochemical conditions from one area migrate into another, potentially affecting contaminant mobility. A recognition of gradients allows the attenuation-affecting conditions of a site to be projected into the future. The Scenarios approach provides a stepwise process to identify an appropriate category of conceptual model and refine it for a specific site. Scenario materials provide links to pertinent sections in the EPA technical protocol and present information about contaminant mobility and important controlling mechanism for attenuation-based remedies based on the categories of conceptual models

Chamber basis of the Orlik-Solomon algebra and Aomoto complex

We introduce a basis of the Orlik-Solomon algebra labeled by chambers, so called chamber basis. We consider structure constants of the Orlik-Solomon algebra with respect to the chamber basis and prove that these structure constants recover D. Cohen's minimal complex from the Aomoto complex.Comment: 16 page

Incident HIV infection has fallen rapidly in men who have sex with men in Melbourne, Australia (2013-2017) but not in the newly-arrived Asian-born.

BACKGROUND: We examined differences in incident HIV infection between newly-arrived Asian-born and other men who have sex with men (MSM) after the introduction of universal HIV treatment guidelines in 2015 and pre-exposure prophylaxis in 2016. METHODS: Clinical, demographic, laboratory and behavioural data on MSM presenting for HIV testing at the Melbourne Sexual Health Centre from July 2013 to June 2017 were extracted. We compared the proportion of newly-arrived (four years or less in Australia), Asian-born and other MSM tested each year who were diagnosed with incident HIV infection (negative test within one year or diagnosis with indeterminate or negative Western Blot). RESULTS: We analysed 35,743 testing episodes in 12,180 MSM, including 2781 testing episodes in 1047 newly-arrived Asian-born MSM. The proportion of other MSM tested each year who were diagnosed with incident HIV infection fell from 0.83% in 2014 to 0.38% in 2017 (p = .001), but did not fall in newly-arrived Asian-born MSM (from 1.18% in 2014 to 1.56% in 2017, p = .76). In the multivariate logistic regression, in 2016/2017 but not in 2014/2015, being newly-arrived Asian-born was associated with an increased odds of diagnosis of incident HIV infection (aOR 3.29, 95%CI 1.82-5.94, p < .001). CONCLUSIONS: The epidemiology of HIV in Melbourne Australia has changed dramatically. While there has been an overall reduction amongst MSM, the incidence of HIV in newly-arrived Asian-born MSM remains high. Failing to address these new inequalities leaves individuals at risk and may offset the population benefit of biomedical HIV prevention

Choosing party leaders: Anglophone democracies, British parties and the limits of comparative politics

Since 1965, Britain’s major political parties have radically, and repeatedly, changed the ways in which they choose their leaders. Building on a recent comparative study of party leadership selection in the five principal Anglophone (‘Westminster’) parliamentary democracies (Cross and Blais, 2012a), this article first outlines a theoretical framework that purports to explain why the major parties in three of those countries, including Britain, have adopted such reform. It then examines why five major British parties have done so since 1965. It argues that, while Cross and Blais’ study makes a significant contribution to our knowledge and understanding of processes of party leadership selection reform in Anglophone parliamentary democracies, it has limited explanatory power when applied to changes enacted by the major parties in modern and contemporary Britain. Instead, the adoption of such reform in the British context is ultimately best understood and explained by examining both the internal politics and external circumstances of individual parties

Characterizing normal crossing hypersurfaces

The objective of this article is to give an effective algebraic characterization of normal crossing hypersurfaces in complex manifolds. It is shown that a hypersurface has normal crossings if and only if it is a free divisor, has a radical Jacobian ideal and a smooth normalization. Using K. Saito's theory of free divisors, also a characterization in terms of logarithmic differential forms and vector fields is found and and finally another one in terms of the logarithmic residue using recent results of M. Granger and M. Schulze.Comment: v2: typos fixed, final version to appear in Math. Ann.; 24 pages, 2 figure

Metabolic, health and lifestyle profiling of breast cancer radiotherapy patients and the risk of developing fatigue

Background: Fatigue is commonly reported by cancer patients. In some instances it can persist after treatment is com-pleted. In order to develop effective treatment strategies it is important to understand the mechanisms underlying the development of fatigue and to be able to predict those that may be at greatest risk of experiencing fatigue during and following treatment. The current paper examines predisposing factors for fatigue including altered fatty acid homeosta-sis in a cohort of breast cancer radiotherapy patients. Methodology: Patients had undergone breast-conserving surgery and adjuvant breast irradiation. Prior to radiotherapy the patients were free from significant fatigue. Levels of fatigue were determined prior to and following radiotherapy using the Functional Assessment of Cancer Therapy fatigue sub-scale. Plasma fatty acid levels, urinary and plasma amino acid levels, blood biochemistry factors and general health and lifestyle characteristics were assessed. Results: Following radiotherapy, significant fatigue affected approximately one third of the 26 patients and these subjects were then assigned to the fatigued cohort. Univariate analysis revealed that higher levels of the fatty acids myristic acid and eicosadienoic acid were present for the fatigued cohort prior to radio-therapy. Multivariate analysis also revealed that fatty acid homeostasis was altered between the fatigued and non-fatigued groups at baseline. Orthogonal partial least squares discriminant analysis of the general health, lifestyle and metabolic data revealed that the fatigued and non-fatigued patients could be clustered into two clearly separate groups. Conclusions: The results supported the proposition that the fatigued patients had an underlying metabolic ho-meostasis which may predispose them to the development of fatigue. Biochemical and general health profiling of breast cancer patients has the potential to identify those at most risk of developing significant fatigue following radiotherapy