Using systems thinking-based risk assessment methods to assess hazardous manual tasks: a comparison of Net-HARMS, EAST-BL, FRAM and STPA

Formal risk assessment is a component of safety management relating to hazardous manual tasks (HMT). Systems thinking approaches are currently gaining interest for supporting safety management. Existing HMT risk assessment methods have been found to be limited in their ability to identify risks across the whole work system; however, systems thinking-based risk assessment (STBRA) methods were not designed for the HMT context and have not been tested in this area. The aim of this study was to compare the performance of four state-of-the-art STBRA methods: Net-HARMS, EAST-BL, FRAM and STPA to determine which would be most useful for identifying HMT risks. Each method was independently applied by one of four analysts to assess the risks associated with a hypothetical HMT system. The outcomes were assessed for alignment with a benchmark analysis. Using signal detection theory (SDT), overall STPA was found to be the best performing method having the highest hit rate, second lowest false alarm rate and highest Matthews Correlation Coefficient of the four methods.Practitioner summary: A comparison of four systems thinking risk assessment methods found that STPA had the highest level of agreement with the benchmark analysis and is the most suitable for practitioners to use to identify the risks associated with HMT systems.

Does body appreciation or satisfaction buffer against idealised functionality-focused images of models?

Research suggests that greater levels of body appreciation and body satisfaction may protect women from negative outcomes when viewing media images of the thin-ideal. In this study, we compared the effectiveness of body appreciation and body satisfaction in ameliorating negative effects from viewing images of the traditional thin-ideal and the newer functional-ideal (i.e., models presented in active stances with a focus on the function of their body). A sample of 122 women (M_age = 24.43 years) from a regional university and the general community was recruited to complete an online study. Participants were randomly allocated to view images of models presented in either an active or posed stance, or images of scenery. Participants completed pre- and post-test measures of appearance and functionality satisfaction, as well as trait measures of body appreciation and satisfaction. Results showed that women had poorer outcomes after viewing the active but not the posed or scenery images. Neither body appreciation nor body satisfaction moderated effects. Active, functional images may be particularly insidious and further research is needed to identify effective protective strategies.

A Randomised Controlled Trial Examining the Effects of Self-Compassion Meditations on Women's Body Image

Although research has suggested that body image improves following self-compassion meditation training, studies have been limited due to the use of a wait-list control group. This study therefore compared the effects of self-compassion meditations to an active control group. Seventy young adult women (17-35 years) were randomly assigned to receive either self-compassion or nature-focused guided imagery meditations. Over one week, participants engaged in two meditations and completed pre- and post-test measures of trait self-compassion, body appreciation, body shame, and appearance-contingent self-worth. A mixed design analysis of variance revealed a main effect of time; women in both meditation groups demonstrated significant increases in self-compassion and body appreciation, and significant reductions in body shame. No effect was found for appearance-contingent self-worth. There were no interactions or main effects for group. Self-compassion may improve body image in women, although there was no evidence for an advantage of self-compassion over guided imagery meditations. Common elements between self-compassion and guided imagery may be a mechanism for improving body image. However, further research is warranted to isolate the effects of these meditations from other specific and non-specific treatment effects. (This study was pre-registered with the Australian New Zealand Clinical Trials Registry, ACTRN12618001814268).

Out of control? Using STAMP to model the control and feedback mechanisms surrounding identity crime in darknet marketplaces

Darknet marketplaces have emerged as a facilitator of identity crime and trading. This study aimed to (1) understand the entities and control and feedback mechanisms that influence identity crime prevention and occurrence on the darknet in the Australian system and to (2) comprehensively identify the implications of control failures across all system levels. The Systems-Theoretic Accident Model and Processes (STAMP) was used to develop an identity crime control structure in consultation with subject matter experts and then the Systems-Theoretic Process Analysis (STPA) was applied. The STPA identified 310 risk states, resulting from control failures and which were associated with the range of agencies, organisations, and individuals present across system levels. As darknet marketplaces rapidly evolve, alignment between these entities is necessary to enable agile system responses. STAMP and STPA have promise in understanding the potential for intervention across all system levels in preventing societal issues such as identity crime.

Who is to blame for crashes involving autonomous vehicles? Exploring blame attribution across the road transport system

The introduction of fully autonomous vehicles is approaching. This warrants a re-consideration of road crash liability, given drivers will have diminished control. This study, underpinned by attribution theory, investigated blame attribution to different road transport system actors following crashes involving manually driven, semi-autonomous and fully autonomous vehicles. It also examined whether outcome severity alters blame ratings. 396 participants attributed blame to five actors (vehicle driver/user, pedestrian, vehicle, manufacturer, government) in vehicle-pedestrian crash scenarios. Different and unique patterns of blame were found across actors, according to the three vehicle types. In crashes involving fully autonomous vehicles, vehicle users received low blame, while vehicle manufacturers and government were highly blamed. There was no difference in the level of blame attributed between high and low severity crashes regarding vehicle type. However, the government received more blame in high severity crashes. The findings have implications for policy and legislation surrounding crash liability. Practitioner summary: Public views relating to blame and liability in transport accidents is a vital consideration for the introduction of new technologies such as autonomous vehicles. This study demonstrates how a systems ergonomics framework can assist to identify the implications of changing public opinion on blame for future road transport systems. Abbreviation: ANOVA: analysis of variance; DAT: defensive attribution theory; IV: independent variable.

A systems thinking perspective on the barriers to treatment access for people with eating disorders

Treatment access remains low for people with eating disorders. In addressing the complexity inherent in this challenge, this article introduces systems thinking and argues that it could provide new insights. Systems thinking views behavior as an emergent property of a system and considers the relationships between technical, organizational, and social components. Several methods used in safety science incorporate this thinking. For example, AcciMap draws focus to the influence of decisions and actions made across hierarchical levels of a system, including those by government, regulatory bodies, management, services, and individuals. By examining the findings of the existing literature on barriers to eating disorder treatment access according to these levels, it is evident that most identified barriers relate to individuals and that further research is needed to consider the influence of high-level stakeholders. Research using systems thinking should consider the causal networks of influence from government, regulatory, and organizational decisions and actions through to outcomes for clinicians and individuals. The understanding of how barriers operate within specific healthcare systems also warrants investigation. Systems thinking is yet to be formally applied in the area of eating disorders and thus represents an opportunity to inform the development and implementation of more effective, system wide interventions.

Using the Event Analysis of Systemic Teamwork (EAST) broken-links approach to understand vulnerabilities to disruption in a darknet market

Darknet markets provide an anonymous, online platform for users to trade illicit drugs, fraudulent identity data, and other commodities. Although law enforcement agencies have been successful in seising many markets, the Darknet is an agile and dynamic environment and market activities often persist and emerge in a new form. Given this constantly changing environment, new ways of disrupting darknet markets are required. This study used Event Analysis of Systemic Teamwork (EAST) to analyse market activity and understand vulnerabilities to disruption. This involved using the EAST broken-links approach to assess the effects of compromising the transmission of information between tasks and between agents. The analysis identified critical vulnerabilities in the system, which included information involved in registering, depositing funds, communicating listing details to buyers, and communicating dispute resolution messages. This study indicates that systems ergonomics methods-in particular, EAST-can provide insight into system vulnerabilities that might be targeted for disruption. Practitioner summary This study provides a conceptualisation of the processes, people, structures, and information involved in the buying and selling of goods on a darknet market. Law enforcement agencies may use broken-links analyses to systematically consider the effects of their interventions.

Consumer and carer perspectives in the development of a mental health research, treatment and teaching facility: A thematic analysis

WHAT IS KNOWN ON THE SUBJECT?: Around the world, recovery has become a focus in mental health policy. The participation of people accessing mental health services (consumers) and carers of such individuals in decision-making related to services forms part of this recovery orientation and studies suggest positive outcomes following such participation. However, little is known about consumer and carer desires at the earliest stages of development of new services. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: Consumers and carers desire changes to how mental health services are provided. Many factors affect consumer and carer experiences, including language use, physical design of spaces, accessibility, consideration of individual needs, practical help and how well care is continued from hospital to community settings. Carers may feel sidelined in treatment and be distressed as a result. They wish to be respected and involved in recovery. Consumers and carers wish for focus on broader health, with care taken to address physical health, psychological needs, social needs and treatment of the whole person rather than just an illness. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Consumers and carers desire partnership with professionals in recovery. Tokenistic participation should be avoided. Flexibility in how services are provided and less formality may help engage consumers and carers. Specifically, professionals may help by linking consumers and carers to services that address practical needs. Professionals should communicate with carers to draw on their expertise about the individual accessing the mental health service and help carers understand how they can assist the individual's recovery.

ABSTRACT

Introduction Recovery-oriented mental health policies recognize consumer and carer participation in service decision-making as essential, but little is known about the views of these individuals in the earliest stages of service development. Aim This study sought consumer and carer perspectives addressing the establishment of a mental health research, treatment and teaching facility in their region. Methods Two 2-hr focus groups were conducted, with separate groups held for mental health consumers (n = 9) and carers (n = 9), respectively. Discussions pertained to mental health literacy, gaps in current services, desires for an ideal facility (in terms of physical design and services offered) and what would help in recovery. Results Inductive thematic analysis was used to generate three themes: care outside of consultations, carer involvement in recovery and holistic approaches to mental health care. Consumers desired a facility that could cater to individual needs. Carers felt excluded in recovery and unable to provide effective support. Both groups preferred holistic approaches to mental health, expressing ambivalence towards medication and hospitalization. Discussion Consumers and carers have many needs that conventional practices may not meet. Implications for practice They have clear desires for equal partnership in recovery and for transformation of conventional treatment methods.

The effects of priming in a cued dot-probe task on appearance-related attentional biases in women

The dot-probe task (DPT) is a reaction time measure of attentional bias. Research using this task has found inconsistent patterns of appearance-related attentional biases in women. This study examined the effects of a novel priming variation of the DPT, which incorporated additional cues into each trial of the task, on measurement of such biases. The study also examined associations between these biases and body image, a component of eating disorder symptomatology. A convenience sample of women from the general community (N = 103) completed body image measures online and attended a laboratory session to complete one of four DPTs: (1) an appearance-cued DPT containing images of thin-ideal models between each trial; (2) neutral-cued DPT containing images of forests; (3) time-delayed DPT controlling for time in place of an image; or (4) typical DPT containing only word stimuli. Women who completed the appearance-cued DPT demonstrated a stronger attentional bias for positive, but not negative, appearance words than women who completed the other DPT versions. Furthermore, for the appearance-cued and time-delayed DPTs, this bias correlated with poorer body image across several indicators (appearance evaluation, body dissatisfaction, self-evaluative salience of appearance, and state body satisfaction). Although it was unexpected that no attentional bias for negative-appearance words was found, the attentional bias for positive-appearance words may suggest that effects were driven by the ego-threat of positive-appearance words. Further research is warranted to determine whether such biases contribute to and maintain body image disturbance and disordered eating.

Attention bias modification produces no changes to appearance-related bias, state or trait body dissatisfaction in nonclinical women

The potential of attention bias modification to reduce appearance-related attentional biases and female body dissatisfaction has not been investigated. Immediate and short-term effects were therefore examined across attentional biases, state and trait body dissatisfaction in a randomised controlled trial consisting of 62 female participants aged 18–35 years. The results show no changes to attentional bias across either the experimental or control condition and no significant changes in body dissatisfaction immediately post-training or at 1–2 weeks follow-up. Single-session attention bias modification protocols may therefore not be sufficient in modifying appearance-based biases and associated disordered body schemas within a nonclinical sample.

A cross-sectional investigation of depressive, anxiety, and stress symptoms and health-behavior participation in Australian university students

Transitioning to university involves a major life change that can have implications for physical and mental health. This study had three objectives: first, assess the mental health and health-behavior participation of Australian university students; second, evaluate clustering of health behaviors; and third, examine how mental health relates to health behaviors. University students (n = 751) enrolled at an Australian regional university completed an online survey containing the Depression, Anxiety, and Stress Scales and a health-behavior questionnaire. Over one-third of students reported mild or higher mental illness symptoms and most reported engaging in multiple unhealthy behaviors. Furthermore, mental health was associated with unhealthy behaviors. For males, depressive symptoms were associated with skipping breakfast and poor sleep quality. For females, depressive symptoms were associated with skipping breakfast, inadequate vigorous physical activity, and short or long sleep hours. Stress symptoms in females were associated with healthy sleep hours, but poor sleep quality. Future research may consider whether an intervention targeting one or two key health behaviors has utility in improving participation in other health behaviors and mental health.

Interleukin-8 stimulates human immunodeficiency virus type 1 replication and is a potential new target for antiretroviral therapy

Production of the C-X-C chemokines interleukin-8 (IL-8) and growth-regulated oncogene alpha (GRO-alpha) in macrophages is stimulated by exposure to human immunodeficiency virus type 1 (HIV-1). We have demonstrated previously that GRO-alpha then stimulates HIV-1 replication in both T lymphocytes and macrophages. Here we demonstrate that IL-8 also stimulates HIV-1 replication in macrophages and T lymphocytes. We further show that increased levels of IL-8 are present in the lymphoid tissue of patients with AIDS. In addition, we demonstrate that compounds which inhibit the actions of IL-8 and GRO-alpha via their receptors, CXCR1 and CXCR2, also inhibit HIV-1 replication in both T lymphocytes and macrophages, indicating potential therapeutic uses for these compounds in HIV-1 infection and AIDS.

Human immunodeficiency virus type 1 (HIV-1)-induced GRO-alpha production stimulates HIV-1 replication in macrophages and T lymphocytes

We examined the early effects of infection by CCR5-using (R5 human immunodeficiency virus [HIV]) and CXCR4-using (X4 HIV) strains of HIV type 1 (HIV-1) on chemokine production by primary human monocyte-derived macrophages (MDM). While R5 HIV, but not X4 HIV, replicated in MDM, we found that the production of the C-X-C chemokine growth-regulated oncogene alpha (GRO-alpha) was markedly stimulated by X4 HIV and, to a much lesser extent, by R5 HIV. HIV-1 gp120 engagement of CXCR4 initiated the stimulation of GRO-alpha production, an effect blocked by antibodies to CXCR4. GRO-alpha then fed back and stimulated HIV-1 replication in both MDM and lymphocytes, and antibodies that neutralize GRO-alpha or CXCR2 (the receptor for GRO-alpha) markedly reduced viral replication in MDM and peripheral blood mononuclear cells. Therefore, activation of MDM by HIV-1 gp120 engagement of CXCR4 initiates an autocrine-paracrine loop that may be important in disease progression after the emergence of X4 HIV.

GLI-2 modulates retroviral gene expression

GLI proteins are involved in the development of mice, humans, zebrafish, Caenorhabditis elegans, Xenopus, and Drosophila. While these zinc finger-containing proteins bind to TG-rich promoter elements and are known to regulate gene expression in C. elegans and Drosophila, mechanistic understanding of how regulation is mediated through naturally occurring transcriptional promoters is lacking. One isoform of human GLI-2 appears to be identical to a factor previously called Tax helper protein (THP), thus named due to its ability to interact with a TG-rich element in the human T-lymphotropic virus type 1 (HTLV-1) enhancer thought to mediate transcriptional stimulation by the Tax protein of HTLV-1. We now demonstrate that, working through its TG-rich binding site and adjacent elements, GLI-2/THP actually suppresses gene expression driven by the HTLV-1 promoter. GLI-2/THP has no effect on the HTLV-2 promoter, activates expression from the promoters of human immunodeficiency virus types 1 and (HIV-1 and -2), and stimulates HIV-1 replication. Both effective suppression and activation of gene expression and viral replication require the first of the five zinc fingers, which is not necessary for DNA binding, to be intact. Thus, not only can GLI-2/THP either activate or suppress gene expression, depending on the promoter, but the same domain (first zinc finger) mediates both effects. These findings suggest a role for GLI-2 in retroviral gene regulation and shed further light on the mechanisms by which GLI proteins regulate naturally occurring promoters.

Human GLI-2 is a tat activation response element-independent Tat cofactor

Zinc finger-containing GLI proteins are involved in the development of Caenorhabditis elegans, Xenopus, Drosophila, zebrafish, mice, and humans. In this study, we show that an isoform of human GLI-2 strongly synergizes with the Tat transactivating proteins of human immunodeficiency virus types 1 and 2 (HIV-1 and -2) and markedly stimulates viral replication. GLI-2 also synergizes with the previously described Tat cofactor cyclin T1 to stimulate Tat function. Surprisingly, GLI-2/Tat synergy is not dependent on either a typical GLI DNA binding site or an intact Tat activation response element but does require an intact TATA box. Thus, GLI-2/Tat synergy results from a mechanism of action which is novel both for a GLI protein and for a Tat cofactor. These findings link the GLI family of transcriptional and developmental regulatory proteins to Tat function and HIV replication.

TNF-alpha inhibits HIV-1 replication in peripheral blood monocytes and alveolar macrophages by inducing the production of RANTES and decreasing C-C chemokine receptor 5 (CCR5) expression

The pathogenesis of HIV-1 infection is influenced by the immunoregulatory responses of the host. Macrophages present in the lymphoid tissue are susceptible to infection with HIV-1, but are relatively resistant to its cytopathic effects and serve as a reservoir for the virus during the course of disease. Previous investigators have demonstrated that increased serum levels of TNF-alpha contribute to the clinical symptoms of AIDS and that TNF-alpha stimulates the production of HIV-1 in chronically infected lymphocytic and monocytic cell lines by increasing HIV-1 gene expression. Although previous studies have suggested that TNF-alpha may increase HIV-1 infection of primary human mononuclear cells, some recent studies have indicated that TNF-alpha suppresses HIV-1 infection of macrophages. We now demonstrate that TNF-alpha suppresses HIV-1 replication in freshly infected peripheral blood monocytes (PBM) and alveolar macrophages (AM) in a dose-dependent manner. As TNF-alpha has been shown to increase the production of C-C chemokine receptor (CCR5)-binding chemokines under certain circumstances, we hypothesized that TNF-alpha inhibits HIV-1 replication by increasing the expression of these HIV-suppressive factors. We now show that TNF-alpha treatment of PBM and AM increases the production of the C-C chemokine, RANTES. Immunodepletion of RANTES alone or in combination with macrophage inflammatory protein-1alpha and -1beta block the ability of TNF-alpha to suppress viral replication in PBM and AM. In addition, we found that TNF-alpha treatment reduces CCR5 expression on PBM and AM. These findings suggest that TNF-alpha plays a significant role in inhibiting monocytotropic strains of HIV-1 by two distinct, but complementary, mechanisms.

Pneumocystis carinii mutations associated with sulfa and sulfone prophylaxis failures in AIDS patients

BACKGROUND

Failures of prophylaxis against Pneumocystis carinii pneumonia (PCP) in AIDS patients do occur, but no evidence for drug resistance has yet been presented.

OBJECTIVE

To determine whether mutations in the sulfa and sulfone drug target are associated with failure of prophylaxis using a sulfa-containing agent.

METHODS

Portions of the gene for P. carinii dihydropteroate synthase (DHPS), the sulfa and sulfone target, from 27 patients (20 of whom had AIDS) diagnosed with PCP between 1976 and 1997 were amplified using polymerase chain reaction and sequenced. Seven of the 27 patients (all of whom had AIDS) were receiving sulfa or sulfone drugs as prophylaxis for PCP.

RESULTS

Mutations were found at only two amino-acid positions and were significantly more common in patients who received sulfa/sulfone prophylaxis. Mutations were observed in five (71%) out of seven isolates from AIDS patients receiving sulfa/sulfone as prophylaxis compared with only two (15%) out of 13 specimens from AIDS patients who did not (P = 0.022). No mutations were seen in isolates from seven non-HIV-infected patients, none of whom were on prophylaxis. Mutations were only observed in specimens obtained in 1995-1997.

CONCLUSIONS

Mutations in two amino-acid positions were significantly more common in AIDS patients with PCP who failed sulfa/sulfone prophylaxis. These amino acids appeared to be directly involved in both substrate and sulfa binding, based on homology to the Escherichia coli DHPS crystal structure. Thus, the results were consistent with the possibility that mutations in the P. carinii DHPS are responsible for some of the failures of sulfa/sulfone prophylaxis in AIDS patients.

Interaction of CED-4 with CED-3 and CED-9: a molecular framework for cell death

Previous genetic studies of the nematode Caenorhabditis elegans identified three important components of the cell death machinery. CED-3 and CED-4 function to kill cells, whereas CED-9 protects cells from death. Here CED-9 and its mammalian homolog Bcl-xL (a member of the Bcl-2 family of cell death regulators) were both found to interact with and inhibit the function of CED-4. In addition, analysis revealed that CED-4 can simultaneously interact with CED-3 and its mammalian counterparts interleukin-1beta-converting enzyme (ICE) and FLICE. Thus, CED-4 plays a central role in the cell death pathway, biochemically linking CED-9 and the Bcl-2 family to CED-3 and the ICE family of pro-apoptotic cysteine proteases.

Dihydropteroate synthase polymorphisms in Pneumocystis carinii

Sulfa drugs are widely used in the treatment and prophylaxis of Pneumocystis carinii pneumonia. The nucleotide sequences of the sulfa target enzyme, dihydropteroate synthase (DHPS), differed substantially in human-, rat-, and mouse-derived P. carinii. Sequence variation also existed in the DHPSs from human-derived isolates. Six nucleotide changes were found in 6 human isolates; each was nonsynonymous and resulted in an amino acid change. Several of these changes were in highly conserved regions and are similar to those that cause sulfa resistance in other organisms. These data suggest that the human-derived P. carinii DHPS may be evolving under positive selective pressure from sulfa drugs.