293 research outputs found

    Mechanism of by product formation from different water matrices by chlorination and chloramination

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    Application of chlorine-based disinfection to drinking water and wastewater leads to the formation of disinfection by-products that are harmful to human health. This paper presents research performed on the formation mechanisms of trihalomethanes (THMs) and nitrosamines (specifically NDMA) from chlorine-based disinfection practices. The formation of THMs and nitrosamines was investigated under a range of water matrices and disinfection conditions by developing a set of laboratory prepared water matrices containing natural organic matter (NOM), bromide and ammonium. In addition, two pretreated surface waters and one secondary treated wastewater effluent were selected to link experimental results to practice. THMs and nitrosamines were measured under a range of chlorine doses along the chlorination breakpoint curve to investigate the effects of chlorine dose, NOM, bromide and ammonium on DBP formation. The formation of NDMA was mainly observed at chlorine doses causing the presence of dichloramine, suggesting that critical NDMA formation pathways involve dichloramine. The highest NDMA concentrations were measured in wastewater effluent, suggesting that the complex NOM composition from wastewater contains many NDMA precursors. THMs were primarily of concern during free chlorine disinfection. Results showed that complex organic matter, specifically humic substances, were primary THM precursors. Humic acids contained fast and slow reacting precursors that were reactive with bromide and chlorine resulting in high THM concentrations. Alternatively, fulvic acids contained slow reacting precursors that were reactive primarily with bromide, resulting in lower overall THM formation with higher bromine incorporation. The results of this research provide professionals in the water industry with a better understanding of THM and NDMA formation and the impact of chlorination practices and water quality on DBP formation

    Cerebrospinal fluid dynamics modulation by diet and cytokines in rats.

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    Background Idiopathic intracranial hypertension (IIH) is a neurological disorder characterised by raised cerebrospinal fluid (CSF) pressure in the absence of any intracranial pathology. IIH mainly affects women with obesity between the ages of 15 and 45. Two possible mechanisms that could explain the increased CSF pressure in IIH are excessive CSF production by the choroid plexus (CP) epithelium or impaired CSF drainage from the brain. However, the molecular mechanisms controlling these mechanisms in IIH remain to be determined. Methods In vivo ventriculo-cisternal perfusion (VCP) and variable rate infusion (VRI) techniques were used to assess changes in rates of CSF secretion and resistance to CSF drainage in female and male Wistar rats fed either a control (C) or high-fat (HF) diet (under anaesthesia with 20 μl/100 g medetomidine, 50 μl/100 g ketamine i.p). In addition, CSF secretion and drainage were assessed in female rats following treatment with inflammatory mediators known to be elevated in the CSF of IIH patients: C-C motif chemokine ligand 2 (CCL2), interleukin (IL)-17 (IL-17), IL-6, IL-1β, tumour necrosis factor-α (TNF-α), as well as glucocorticoid hydrocortisone (HC). Results Female rats fed the HF diet had greater CSF secretion compared to those on control diet (3.18 ± 0.12 μl/min HF, 1.49 ± 0.15 μl/min control). Increased CSF secretion was seen in both groups following HC treatment (by 132% in controls and 114% in HF) but only in control rats following TNF-α treatment (137% increase). The resistance to CSF drainage was not different between control and HF fed female rats (6.13 ± 0.44 mmH O min/μl controls, and 7.09 ± 0.26 mmH O min/μl HF). and when treated with CCL2, both groups displayed an increase in resistance to CSF drainage of 141% (controls) and 139% (HF) indicating lower levels of CSF drainage. Conclusions Weight loss and therapies targeting HC, TNF-α and CCL2, whether separately or in combination, may be beneficial to modulate rates of CSF secretion and/or resistance to CSF drainage pathways, both factors likely contributing to the raised intracranial pressure (ICP) observed in female IIH patients with obesity.</p

    Management of Chlamydia Cases in Australia (MoCCA): protocol for a non-randomised implementation and feasibility trial

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    INTRODUCTION: The sexually transmitted infection chlamydia can cause significant complications, particularly among people with female reproductive organs. Optimal management includes timely and appropriate treatment, notifying and treating sexual partners, timely retesting for reinfection and detecting complications including pelvic inflammatory disease (PID). In Australia, mainstream primary care (general practice) is where most chlamydia infections are diagnosed, making it a key setting for optimising chlamydia management. High reinfection and low retesting rates suggest partner notification and retesting are not uniformly provided. The Management of Chlamydia Cases in Australia (MoCCA) study seeks to address gaps in chlamydia management in Australian general practice through implementing interventions shown to improve chlamydia management in specialist services. MoCCA will focus on improving retesting, partner management (including patient-delivered partner therapy) and PID diagnosis. METHODS AND ANALYSIS: MoCCA is a non-randomised implementation and feasibility trial aiming to determine how best to implement interventions to support general practice in delivering best practice chlamydia management. Our method is guided by the Consolidated Framework for Implementation Research and the Normalisation Process Theory. MoCCA interventions include a website, flow charts, fact sheets, mailed specimen kits and autofills to streamline chlamydia consultation documentation. We aim to recruit 20 general practices across three Australian states (Victoria, New South Wales, Queensland) through which we will implement the interventions over 12–18 months. Mixed methods involving qualitative and quantitative data collection and analyses (observation, interviews, surveys) from staff and patients will be undertaken to explore our intervention implementation, acceptability and uptake. Deidentified general practice and laboratory data will be used to measure pre-post chlamydia testing, retesting, reinfection and PID rates, and to estimate MoCCA intervention costs. Our findings will guide scale-up plans for Australian general practice. ETHICS AND DISSEMINATION: Ethics approval was obtained from The University of Melbourne Human Research Ethics Committee (Ethics ID: 22665). Findings will be disseminated via conference presentations, peer-reviewed publications and study reports

    A fractional Hawkes process II: further characterization of the process

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    We characterize a Hawkes point process with kernel proportional to the probability density function of Mittag-Leffler random variables. This kernel decays as a power law with exponent β+1(1,2]\beta +1 \in (1,2]. Several analytical results can be proved, in particular for the expected intensity of the point process and for the expected number of events of the counting process. These analytical results are used to validate algorithms that numerically invert the Laplace transform of the expected intensity as well as Monte Carlo simulations of the process. Finally, Monte Carlo simulations are used to derive the full distribution of the number of events. The algorithms used for this paper are available at {\tt https://github.com/habyarimanacassien/Fractional-Hawkes}

    A cost-effectiveness analysis of provider and community interventions to improve the treatment of uncomplicated malaria in Nigeria: study protocol for a randomized controlled trial.

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    BACKGROUND: There is mounting evidence of poor adherence by health service personnel to clinical guidelines for malaria following a symptomatic diagnosis. In response to this, the World Health Organization (WHO) recommends that in all settings clinical suspicion of malaria should be confirmed by parasitological diagnosis using microscopy or Rapid Diagnostic Test (RDT). The Government of Nigeria plans to introduce RDTs in public health facilities over the coming year. In this context, we will evaluate the effectiveness and cost-effectiveness of two interventions designed to support the roll-out of RDTs and improve the rational use of ACTs. It is feared that without supporting interventions, non-adherence will remain a serious impediment to implementing malaria treatment guidelines. METHODS/DESIGN: A three-arm stratified cluster randomized trial is used to compare the effectiveness and cost-effectiveness of: (1) provider malaria training intervention versus expected standard practice in malaria diagnosis and treatment; (2) provider malaria training intervention plus school-based intervention versus expected standard practice; and (3) the combined provider plus school-based intervention versus provider intervention alone. RDTs will be introduced in all arms of the trial. The primary outcome is the proportion of patients attending facilities that report a fever or suspected malaria and receive treatment according to malaria guidelines. This will be measured by surveying patients (or caregivers) as they exit primary health centers, pharmacies, and patent medicine dealers. Cost-effectiveness will be presented in terms of the primary outcome and a range of secondary outcomes, including changes in provider and community knowledge. Costs will be estimated from both a societal and provider perspective using standard economic evaluation methodologies. TRIAL REGISTRATION: Clinicaltrials.gov NCT01350752

    Change and Exchange: Economies of Literature and Knowledge in Early Modern Europe

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    The introductory essay outlines the way in which Change and Exchange places literature, and, in a wider sense, imaginative practice, at the centre of early modern economic knowledge. Probing the affinity between economic and metaphorical experience in terms of the transactional processes of change and exchange, it sets up the parameters within which the essays in the volume collectively forge a language to grasp early modern economic phenomena and their epistemic dimensions. It prepares the reader for the stimulating combination of materials that the book presents: the range of generic contexts engendered by emergent economic practices, structures of feeling and modes of knowing made available by new economic relations, and economies of transformation in discursive domains that are distinct from ‘economics’ as we understand it but cognate in their intuition of change and exchange as shaping agents

    Using systems science to understand the determinants of inequities in healthy eating

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    Introduction: Systems thinking has emerged in recent years as a promising approach to understanding and acting on the prevention and amelioration of non-communicable disease. However, the evidence on inequities in non-communicable diseases and their risks factors, particularly diet, has not been examined from a systems perspective. We report on an approach to developing a system oriented policy actor perspective on the multiple causes of inequities in healthy eating. Methods: Collaborative conceptual modelling workshops were held in 2015 with an expert group of representatives from government, non-government health organisations and academia in Australia. The expert group built a systems model using a system dynamics theoretical perspective. The model developed from individual mind maps to pair blended maps, before being finalised as a causal loop diagram. Results: The work of the expert stakeholders generated a comprehensive causal loop diagram of the determinants of inequity in healthy eating (the HE2Diagram). This complex dynamic system has seven sub-systems: (1) food supply and environment; (2) transport; (3) housing and the built environment; (4) employment; (5) social protection; (6) health literacy; and (7) food preferences. Discussion: The HE2causal loop diagram illustrates the complexity of determinants of inequities in healthy eating. This approach, both the process of construction and the final visualisation, can provide the basis for planning the prevention and amelioration of inequities in healthy eating that engages with multiple levels of causes and existing policies and programs

    Social prescribing for people living with dementia (PLWD) and their carers: what works, for whom, under what circumstances and why – protocol for a complex intervention systematic review

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    Introduction: Dementia is a complex medical condition that poses significant challenges to healthcare systems and support services. People living with dementia (PLWD) and their carers experience complex needs often exacerbated by social isolation and challenges in accessing support. Social prescribing (SP) seeks to enable PLWD and their carers to access community and voluntary sector resources to support them address such needs. Existing research, however, does not describe what SP interventions are currently in place in dementia care. Little is known about the needs these interventions are designed to address, the reasons that lead PLWD and their carers to participate in them, their effectiveness and the extent to which they could increase positive health outcomes if adopted and how. Methods and analysis: A complex intervention systematic review of SP for PLWD and/or their carers will be conducted using an iterative logic model approach. Six electronic (MEDLINE, EMBASE, PsycINFO, CINAHL, Scopus and Cochrane/CENTRAL) and two grey literature databases (EThOS and CORE) were searched for publications between 1 January 2003 and June 2023, supplemented by handsearching of reference lists of included studies. Study selection, data extraction and risk of bias assessment, using Gough’s Weight of Evidence Framework, will be independently performed by two reviewers. A narrative approach will be employed to synthesise and report quantitative and qualitative data. Reporting will be informed by the Preferred Reporting Items for Systematic Review and Meta-Analysis Complex Interventions extension statement and checklist. Ethics and dissemination: No ethical approval is required due to this systematic review operating only with secondary sources. Findings will be disseminated through peer-reviewed publications, conference presentations and meetings with key stakeholders including healthcare professionals, patient and carer groups, community organisations (eg, the Social Prescribing Network and the Evidence Collaborative at the National Academy for Social Prescribing), policymakers and funding bodies

    An analysis of potential barriers and enablers to regulating the television marketing of unhealthy foods to children at the state government level in Australia

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    Background In Australia there have been many calls for government action to halt the effects of unhealthy food marketing on children\u27s health, yet implementation has not occurred. The attitudes of those involved in the policy-making process towards regulatory intervention governing unhealthy food marketing are not well understood. The objective of this research was to understand the perceptions of senior representatives from Australian state and territory governments, statutory authorities and non-government organisations regarding the feasibility of state-level government regulation of television marketing of unhealthy food to children in Australia.Method Data from in-depth semi-structured interviews with senior representatives from state and territory government departments, statutory authorities and non-government organisations (n=22) were analysed to determine participants\u27 views about regulation of television marketing of unhealthy food to children at the state government level. Data were analysed using content and thematic analyses.Results Regulation of television marketing of unhealthy food to children was supported as a strategy for obesity prevention. Barriers to implementing regulation at the state level were: the perception that regulation of television advertising is a Commonwealth, not state/territory, responsibility; the power of the food industry and; the need for clear evidence that demonstrates the effectiveness of regulation. Evidence of community support for regulation was also cited as an important factor in determining feasibility.Conclusions The regulation of unhealthy food marketing to children is perceived to be a feasible strategy for obesity prevention however barriers to implementation at the state level exist. Those involved in state-level policy making generally indicated a preference for Commonwealth-led regulation. This research suggests that implementation of regulation of the television marketing of unhealthy food to children should ideally occur under the direction of the Commonwealth government. However, given that regulation is technically feasible at the state level, in the absence of Commonwealth action, states/territories could act independently. The relevance of our findings is likely to extend beyond Australia as unhealthy food marketing to children is a global issue.<br /
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