Integration of psychological models in the design of artificial creatures

Artificial creatures form an increasingly important component of interactive computer games. Examples of such creatures exist which can interact with each other and the game player and learn from their experiences. However, we argue, the design of the underlying architecture and algorithms has to a large extent overlooked knowledge from psychology and cognitive sciences. We explore the integration of observations from studies of motivational systems and emotional behaviour into the design of artificial creatures. An initial implementation of our ideas using the “sim agent” toolkit illustrates that physiological models can be used as the basis for creatures with animal like behaviour attributes. The current aim of this research is to increase the “realism” of artificial creatures in interactive game-play, but it may have wider implications for the development of AI

Deep-water seagrasses in the tropics: resilience, recovery and establishing thresholds and drivers of change

Global seagrass research and assessment efforts have focused on shallow coastal and estuarine seagrass populations. Comparatively little is known about the dynamics of deep-water (>10m) seagrasses despite evidence they form extensive meadows in some parts of the world and may be highly productive compared with their shallow counterparts. Deep-water seagrasses are subject to a similar range of anthropogenic threats as shallow meadows particularly along the Great Barrier Reef (GBR) in Queensland, where they occur close to major population centres and adjacent to the coast. We examine the dynamics of deep-water seagrass populations in the GBR through a range of research studies including long term (>8 years) assessments of change; impacts of major dredging programs; resilience and recovery from severe tropical storms and; targeted research investigating the drivers, thresholds and tolerances behind seasonal and inter-annual change. Collectively these re- search programs have provided new insight into deep-water seagrass dynamics. Despite considerable inter-annual variability deep-water seagrasses had a regular annual pattern of occurrence at some locations, a low level of resilience to reduced water quality, but a high capacity for recolonisation on the cessation of impacts. While susceptible to large scale loss from severe storms these meadows were quick to re-establish compared with nearby shallow coastal seagrasses. The results of the work are establishing a series of key management thresholds and stress indictors that can be applied to ensure greater protection of these seagrasses

The influence of light and tidal exposure on primary production in the tropical seagrass Zostera capricorni and Halophila ovalis

The growth, survival and depth penetration of seagrass is directly related to light availability, which drives photosynthesis. The amount of light reaching seagrass beds is highly variable and can be easily disrupted by human activities, such as dredging. Dredging results in increased turbidity and decreased light penetration to the seagrass beds, invariably influencing overall productivity and seagrass health. To better understand seagrass light requirements and resilience to environmental stressors such as dredging requires knowledge on seagrass photophysiology and the impact air exposure during a tidal cycle has on photosynthesis. Oxygen, fluorescence and bio-optical properties were measured over a tidal cycle in seagrass beds of Zostera capricorni and Halophila ovalis in Gladstone Harbour to provide insight into the variability in carbon production in intertidal seagrass meadows. Both species showed an increase in photosynthetic activity with increased irradiance as the tide receded. However, sensitivity to desiccation was observed during air-exposure with a significant decline in photosynthesis irrespective of increased light availability. Understanding the complex dynamics of seagrass photosynthesis over a tidal cycle will help in the mitigation of dredging-related light loss to Gladstone seagrass meadows

Identification of key residues that confer Rhodobacter sphaeroides LPS activity at horse TLR4/MD-2.

The molecular determinants underpinning how hexaacylated lipid A and tetraacylated precursor lipid IVa activate Toll-like receptor 4 (TLR4) are well understood, but how activation is induced by other lipid A species is less clear. Species specificity studies have clarified how TLR4/MD-2 recognises different lipid A structures, for example tetraacylated lipid IVa requires direct electrostatic interactions for agonism. In this study, we examine how pentaacylated lipopolysaccharide from Rhodobacter sphaeroides (RSLPS) antagonises human TLR4/MD-2 and activates the horse receptor complex using a computational approach and cross-species mutagenesis. At a functional level, we show that RSLPS is a partial agonist at horse TLR4/MD-2 with greater efficacy than lipid IVa. These data suggest the importance of the additional acyl chain in RSLPS signalling. Based on docking analysis, we propose a model for positioning of the RSLPS lipid A moiety (RSLA) within the MD-2 cavity at the TLR4 dimer interface, which allows activity at the horse receptor complex. As for lipid IVa, RSLPS agonism requires species-specific contacts with MD-2 and TLR4, but the R2 chain of RSLA protrudes from the MD-2 pocket to contact the TLR4 dimer in the vicinity of proline 442. Our model explains why RSLPS is only partially dependent on horse TLR4 residue R385, unlike lipid IVa. Mutagenesis of proline 442 into a serine residue, as found in human TLR4, uncovers the importance of this site in RSLPS signalling; horse TLR4 R385G/P442S double mutation completely abolishes RSLPS activity without its counterpart, human TLR4 G384R/S441P, being able to restore it. Our data highlight the importance of subtle changes in ligand positioning, and suggest that TLR4 and MD-2 residues that may not participate directly in ligand binding can determine the signalling outcome of a given ligand. This indicates a cooperative binding mechanism within the receptor complex, which is becoming increasingly important in TLR signalling.This work was supported by a project grant from the Horserace Betting Levy Board to CEB and a Horserace Betting Levy Board Veterinary Research Training Scholarship to KLI. This work was also supported by a Wellcome Trust program grant to NJG and CEB. CEB is a BBSRC Research Development Fellow.This is the final version of the article. It first appeared from PLOS at http://dx.doi.org/10.1371/journal.pone.0098776

A report card approach to describe temporal and spatial trends in parameters for coastal seagrass habitats

Report cards that are designed to monitor environmental trends have the potential to provide a powerful communication tool because they are easy to understand and accessible to the general public, scientists, managers and policy makers. Given this functionality, they are increasingly popular in marine ecosystem reporting. We describe a report card method for seagrass that incorporates spatial and temporal variability in three metrics—meadow area, species and biomass—developed using long-term (greater than 10 years) monitoring data. This framework summarises large amounts of spatially and temporally complex data to give a numeric score that provides reliable comparisons of seagrass condition in both persistent and naturally variable meadows. We provide an example of how this is applied to seagrass meadows in an industrial port in the Great Barrier Reef World Heritage Area of north-eastern Australia

High variability of Blue Carbon storage in seagrass meadows at the estuary scale

Seagrass meadows are considered important natural carbon sinks due to their capacity to store organic carbon (Corg) in sediments. However, the spatial heterogeneity of carbon storage in seagrass sediments needs to be better understood to improve accuracy of blue carbon assessments, particularly when strong gradients are present. We performed an intensive coring study within a sub-tropical estuary to assess the spatial variability in sedimentary Corg associated with seagrasses, and to identify the key factors promoting this variability. We found a strong spatial pattern within the estuary, from 52.16 mg Corg cm-3 in seagrass meadows in the upper parts, declining to 1.06 mg Corg cm-3 in seagrass meadows at the estuary mouth, despite a general gradient of increasing seagrass cover and seagrass habitat extent in the opposite direction. The sedimentary Corg underneath seagrass meadows came principally from allochthonous (non-seagrass) sources (~70-90%), while the contribution of seagrasses was low (~10-30%) throughout the entire estuary. Our results showed that Corg stored in sediments of seagrass meadows can be highly variable within an estuary, attributed largely to accumulation of fine sediments and inputs of allochthonous sources. Local features and the existence of spatial gradients must be considered in blue carbon estimates in coastal ecosystems

A Case of Infectious Purpura Fulminans: An Unusual Organism and Method of Diagnosis

Infectious purpura fulminans is a rapidly progressive skin necrosis that carries a mortality rate of 30%. Here, we described a case of infectious purpura fulminans caused by Capnocytophaga diagnosed by a blood film

Comparing socially disadvantaged smokers who agree and decline to participate in a randomised smoking cessation trial

Objectives: This study examined sociodemographic, smoking and psychosocial characteristics associated with consent to participate in a smoking cessation trial for socially disadvantaged smokers. Design: Baseline data were collected prior to seeking consent for the Call it Quits, a randomised controlled trial. Setting: An Australian social and community service organisation. Sociodemographic, smoking and psychosocial characteristics were compared between smokers who agreed or declined to participate. Participants: Of the 584 smokers invited to participate, 431 (74%) consented and 153 (26%) declined. Results: Logistic regression modelling indicates the ORs of participation were twice as high for those reporting 'high' motivation to quit compared to the 'moderate' motivation group, and five times higher than the 'low' motivation group ( p=0.007). The ORs of consenting were higher for those with a preference for gradual reduction in cigarettes in quit attempts compared with 'no preference'. The ORs were lower for those reporting 'don't know' regarding their enjoyment of smoking compared to 'not at all' enjoying smoking, and reporting that fewer of their family or friends smoked compared to 'most or all'. Conclusions: This study is the first to examine the characteristics of socially disadvantaged smokers who consent or decline to participate in a smoking cessation trial. Low-income smokers who are motivated to quit, are not enjoying smoking, had family or friends who smoked, and who are interested in gradual cessation approaches may be more likely to participate in a smoking cessation trial

Protocol of a multi-centre randomised controlled trial of a web-based information intervention with nurse-delivered telephone support for haematological cancer patients and their support persons

BACKGROUND: High rates of anxiety, depression and unmet needs are evident amongst haematological cancer patients undergoing treatment and their Support Persons. Psychosocial distress may be minimised by ensuring that patients are sufficiently involved in decision making, provided with tailored information and adequate preparation for potentially threatening procedures. To date, there are no published studies evaluating interventions designed to reduce psychosocial distress and unmet needs specifically in patients with haematological cancers and their Support Persons. This study will examine whether access to a web-based information tool and nurse-delivered telephone support reduces depression, anxiety and unmet information needs for haematological cancer patients and their Support Persons. METHODS/DESIGN: A non-blinded, parallel-group, multi-centre randomised controlled trial will be conducted to compare the effectiveness of a web-based information tool and nurse-delivered telephone support with usual care. Participants will be recruited from the haematology inpatient wards of five hospitals in New South Wales, Australia. Patients diagnosed with acute myeloid leukaemia, acute lymphoblastic leukaemia, Burkitt’s lymphoma, Lymphoblastic lymphoma (B or T cell), or Diffuse Large B-Cell lymphoma and their Support Persons will be eligible to participate. Patients and their Support Persons will be randomised as dyads. Participants allocated to the intervention will receive access to a tailored web-based tool that provides accurate, up-to-date and personalised information about: cancer and its causes; treatment options including treatment procedures information; complementary and alternative medicine; and available support. Patients and Support Persons will complete self-report measures of anxiety, depression and unmet needs at 2, 4, 8 and 12 weeks post-recruitment. Patient and Support Person outcomes will be assessed independently. DISCUSSION: This study will assess whether providing information and support using web-based and telephone support address the major psychosocial challenges faced by haematological patients and their Support Persons. The approach, if found to be effective, has potential to improve psychosocial outcomes for haematological and other cancer patients, reduce the complexity and burden of meeting patients’ psychosocial needs for health care providers with high potential for translation into clinical practice. .The study is funded by Cancer Institute New South Wales (10/THS/2-14). This research was also supported by a Strategic Research Partnership grant provided by Cancer Council New South Wales to the Newcastle Cancer Control Collaborative, and infrastructure funding from the Hunter Medical Research Institute. Dr. Jamie Bryant is supported by an Australian Research Council Post-Doctoral Industry Fellowship. A/Prof Christine Paul is supported by an NHMRC Career Development Fellowship. Dr. Flora Tzelepis was supported by a Leukaemia Foundation of Australia and Cure Cancer Australia Foundation Post-Doctoral Research Fellowship

Treatments for hyperemesis gravidarum and nausea and vomiting in pregnancy:A systematic review and economic assessment

Background: Nausea and vomiting in pregnancy (NVP) affects up to 85% of all women during pregnancy, but for the majority self-management suffices. For the remainder, symptoms are more severe and the most severe form of NVP – hyperemesis gravidarum (HG) – affects 0.3–1.0% of pregnant women. There is no widely accepted point at which NVP becomes HG. Objectives: This study aimed to determine the relative clinical effectiveness and cost-effectiveness of treatments for NVP and HG. Data sources: MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, PsycINFO, Commonwealth Agricultural Bureaux (CAB) Abstracts, Latin American and Caribbean Health Sciences Literature, Allied and Complementary Medicine Database, British Nursing Index, Science Citation Index, Social Sciences Citation Index, Scopus, Conference Proceedings Index, NHS Economic Evaluation Database, Health Economic Evaluations Database, China National Knowledge Infrastructure, Cochrane Database of Systematic Reviews and Database of Abstracts of Reviews of Effects were searched from inception to September 2014. References from studies and literature reviews identified were also examined. Obstetric Medicine was hand-searched, as were websites of relevant organisations. Costs came from NHS sources. Review methods: A systematic review of randomised and non-randomised controlled trials (RCTs) for effectiveness, and population-based case series for adverse events and fetal outcomes. Treatments: vitamins B6 and B12, ginger, acupressure/acupuncture, hypnotherapy, antiemetics, dopamine antagonists, 5-hydroxytryptamine receptor antagonists, intravenous (i.v.) fluids, corticosteroids, enteral and parenteral feeding or other novel treatment. Two reviewers extracted data and quality assessed studies. Results were narratively synthesised; planned meta-analysis was not possible due to heterogeneity and incomplete reporting. A simple economic evaluation considered the implied values of treatments. Results: Seventy-three studies (75 reports) met the inclusion criteria. For RCTs, 33 and 11 studies had a low and high risk of bias respectively. For the remainder (n = 20) it was unclear. The non-randomised studies (n = 9) were low quality. There were 33 separate comparators. The most common were acupressure versus placebo (n = 12); steroid versus usual treatment (n = 7); ginger versus placebo (n = 6); ginger versus vitamin B6 (n = 6); and vitamin B6 versus placebo (n = 4). There was evidence that ginger, antihistamines, metoclopramide (mild disease) and vitamin B6 (mild to severe disease) are better than placebo. Diclectin® [Duchesnay Inc.; doxylamine succinate (10 mg) plus pyridoxine hydrochloride (10 mg) slow release tablet] is more effective than placebo and ondansetron is more effective at reducing nausea than pyridoxine plus doxylamine. Diclectin before symptoms of NVP begin for women at high risk of severe NVP recurrence reduces risk of moderate/severe NVP compared with taking Diclectin once symptoms begin. Promethazine is as, and ondansetron is more, effective than metoclopramide for severe NVP/HG. I.v. fluids help correct dehydration and improve symptoms. Dextrose saline may be more effective at reducing nausea than normal saline. Transdermal clonidine patches may be effective for severe HG. Enteral feeding is effective but extreme method treatment for very severe symptoms. Day case management for moderate/severe symptoms is feasible, acceptable and as effective as inpatient care. For all other interventions and comparisons, evidence is unclear. The economic analysis was limited by lack of effectiveness data, but comparison of costs between treatments highlights the implications of different choices. Limitations: The main limitations were the quantity and quality of the data available. Conclusion: There was evidence of some improvement in symptoms for some treatments, but these data may not be transferable across disease severities. Methodologically sound and larger trials of the main therapies considered within the UK NHS are needed. Study registration: This study is registered as PROSPERO CRD42013006642. Funding: The National Institute for Health Research Health Technology Assessment programme