Recruitment of a threatened foundation oyster species varies with large and small spatial scales.

Understanding how habitat attributes (e.g., patch area and sizes, connectivity) control recruitment and how this is modified by processes operating at larger spatial scales is fundamental to understanding population sustainability and developing successful long-term restoration strategies for marine foundation species-including for globally threatened reef-forming oysters. In two experiments, we assessed the recruitment and energy reserves of oyster recruits onto remnant reefs of the oyster Saccostrea glomerata in estuaries spanning 550 km of coastline in southeastern Australia. In the first experiment, we determined whether recruitment of oysters to settlement plates in three estuaries was correlated with reef attributes within patches (distances to patch edges and surface elevation), whole-patch attributes (shape and size of patches), and landscape attributes (connectivity). We also determined whether environmental factors (e.g., sedimentation and water temperature) explained the differences among recruitment plates. We also tested whether differences in energy reserves of recruits could explain the differences between two of the estuaries (one high- and one low-sedimentation estuary). In the second experiment, across six estuaries (three with nominally high and three with nominally low sedimentation rates), we tested the hypothesis that, at the estuary scale, recruitment and survival were negatively correlated to sedimentation. Overall, total oyster recruitment varied mostly at the scale of estuaries rather than with reef attributes and was negatively correlated with sedimentation. Percentage recruit survival was, however, similar among estuaries, although energy reserves and condition of recruits were lower at a high- compared to a low-sediment estuary. Within each estuary, total oyster recruitment increased with patch area and decreased with increasing tidal height. Our results showed that differences among estuaries have the largest influence on oyster recruitment and recruit health and this may be explained by environmental processes operating at the same scale. While survival was high across all estuaries, growth and reproduction of oysters on remnant reefs may be affected by sublethal effects on the health of recruits in high-sediment estuaries. Thus, restoration programs should consider lethal and sublethal effects of whole-estuary environmental processes when selecting sites and include environmental mitigation actions to maximize recruitment success.

Juvenile waiting stage crown-of-thorns sea stars are resilient in heatwave conditions that bleach and kill corals.

The juveniles of predatory sea stars can remain in their recruitment-nursery habitat for some time before their ontogenetic shift to the adult habitat and diet. These small juveniles are vulnerable to a range of factors with their sensitivity amplified by climate change-driven ocean warming. We investigate the thermal tolerance of the waiting stage herbivorous juveniles of the keystone coral predator, the crown-of-thorns sea star (COTS, Acanthaster sp.), in context with the degree heating weeks (DHW) model that predicts coral bleaching and mass mortality. In temperature treatments ranging from +1 to 3°C in prolonged heatwave acclimation conditions, the juveniles exhibited ~100% survival in DHW scenarios that trigger coral bleaching (4 DHW), resulting in mass mortality of corals (8 DHW) and extreme conditions well beyond those that kill corals (12 DHW). This indicates that herbivorous juvenile COTS are far more resistant to heatwave conditions than the coral prey of the adults. The juveniles exhibited higher activity (righting) and metabolic rate after weeks in increased temperature. In separate acute temperature experiments, the upper thermal limit of the juveniles was 34-36°C. In a warming world, juvenile COTS residing in their coral rubble nursery habitat will benefit from an increase in the extent of this habitat due to coral mortality. The juveniles have potential for long-term persistence as herbivores as they wait for live coral to recover before becoming coral predators, thereby serving as a proximate source of COTS outbreaks on reefs already in a tenuous state due to climate change.

Does a powerlifting inspired exercise programme better compliment pain education compared to bodyweight exercise for people with chronic low back pain? A multicentre, single-blind, randomised controlled trial.

BACKGROUND: Contemporary management of chronic low back pain involves combined exercise and pain education. Currently, there is a gap in the literature for whether any exercise mode better pairs with pain education. The purpose of this study was to compare general callisthenic exercise with a powerlifting style programme, both paired with consistent pain education, for chronic low back pain. We hypothesised powerlifting style training may better compliment the messages of pain education. METHODS: An 8-week single-blind randomised controlled trial was conducted comparing bodyweight exercise (n = 32) with powerlifting (n = 32) paired with the same education, for people with chronic low back pain. Exercise sessions were one-on-one and lasted 60-min, with the last 5-15 min comprising pain education. Pain, disability, fear, catastrophizing, self-efficacy, anxiety, and depression were measured at baseline, 8-weeks, 3-months, and 6-months. RESULTS: No significant between-group differences were observed for pain (p≥0.40), or disability (p≥0.45) at any time-point. Within-group differences were significantly improved for pain (p ≤ 0.04) and disability (p ≤ 0.04) at all time-points for both groups, except 6-month disability in the bodyweight group (p = 0.1). Behavioural measures explained 39-60% of the variance in changes in pain and disability at each time-point, with fear and self-efficacy emerging as significant in these models (p ≤ 0.001). CONCLUSIONS: Both powerlifting and bodyweight exercise were safe and beneficial when paired with pain education for chronic low back pain, with reductions in pain and disability associated with improved fear and self-efficacy. This study provides opportunity for practitioners to no longer be constrained by systematic approaches to chronic low back pain.

Ocean acidification but not warming alters sex determination in the Sydney rock oyster, Saccostrea glomerata.

Whether sex determination of marine organisms can be altered by ocean acidification and warming during this century remains a significant, unanswered question. Here, we show that exposure of the protandric hermaphrodite oyster, Saccostrea glomerata to ocean acidification, but not warming, alters sex determination resulting in changes in sex ratios. After just one reproductive cycle there were 16% more females than males. The rate of gametogenesis, gonad area, fecundity, shell length, extracellular pH and survival decreased in response to ocean acidification. Warming as a sole stressor slightly increased the rate of gametogenesis, gonad area and fecundity, but this increase was masked by the impact of ocean acidification at a level predicted for this century. Alterations to sex determination, sex ratios and reproductive capacity will have flow on effects to reduce larval supply and population size of oysters and potentially other marine organisms.

Adult exposure to ocean acidification is maladaptive for larvae of the Sydney rock oyster Saccostrea glomerata in the presence of multiple stressors.

Parental effects passed from adults to their offspring have been identified as a source of rapid acclimation that may allow marine populations to persist as our surface oceans continue to decrease in pH. Little is known, however, whether parental effects are beneficial for offspring in the presence of multiple stressors. We exposed adults of the oyster Saccostrea glomerata to elevated CO2 and examined the impacts of elevated CO2 (control = 392; 856 µatm) combined with elevated temperature (control = 24; 28°C), reduced salinity (control = 35; 25) and reduced food concentration (control = full; half diet) on their larvae. Adult exposure to elevated CO2 had a positive impact on larvae reared at elevated CO2 as a sole stressor, which were 8% larger and developed faster at elevated CO2 compared with larvae from adults exposed to ambient CO2 These larvae, however, had significantly reduced survival in all multistressor treatments. This was particularly evident for larvae reared at elevated CO2 combined with elevated temperature or reduced food concentration, with no larvae surviving in some treatment combinations. Larvae from CO2-exposed adults had a higher standard metabolic rate. Our results provide evidence that parental exposure to ocean acidification may be maladaptive when larvae experience multiple stressors.

Exercise Snacks and Other Forms of Intermittent Physical Activity for Improving Health in Adults and Older Adults: A Scoping Review of Epidemiological, Experimental and Qualitative Studies.

Exercise snacks, including other variants of brief intermittent bouts, are an emerging approach for increasing physical activity, although their operationalisation is unstandardised and their health benefits remain unclear. This scoping review aimed to explore characterisations of exercise snacks and summarise their effects on health in adults and older adults. Clinical trial registers (clinicaltrials.gov and ANZCTR) and electronic databases (PubMed, CINAHL, CENTRAL, PsycINFO) were searched from inception to 1 June 2023, for ongoing and published studies of exercise snacks. Backwards and forwards citation tracking was also conducted to identify additional eligible studies. Studies were included if they investigated exercise snacks-brief intermittent bouts of physical activity spread across the day-in adults or older adults. We included epidemiological, experimental, quasi-experimental and qualitative studies that examined the effect of exercise snacks on any health outcomes or described barriers to and enablers of these approaches. Thirty-two studies were included (7 trial registers, 1 published protocol, 3 epidemiological studies and 20 trials reported across 21 studies). Three main terms were used to describe exercise snacks: exercise snack(ing), snacktivity and vigorous intermittent lifestyle physical activity (VILPA). Participants were predominantly physically inactive but otherwise healthy adults or older adults. Exercise snacks were feasible and appeared safe. Epidemiological studies showed steep, near-linear associations of VILPA with reduced all-cause, cardiovascular and cancer mortality as well as reduced incidence of major adverse cardiovascular events and cancer. The limited trial evidence showed exercise snacks had modest effects on improving cardiorespiratory fitness, whereas effects on physical function, mood, quality of life and other health outcomes were equivocal. In conclusion, exercise snacks appear feasible and safe for adults and older adults and may have promising health benefits, but this is mostly based on findings from a limited number of small quasi-experimental studies, small randomised trials or qualitative studies. More studies are needed in individuals with chronic disease. This emerging physical activity approach may have appeal for individuals who find structured exercise unfeasible.Registration https://osf.io/qhu24/.

How and why do people with chronic low back pain modify their physical activity? A mixed-methods survey.

BACKGROUND: This study investigated the impact of Chronic Low Back Pain (CLBP) on individuals' physical activity (PA) behaviours, specifically, how they modify, cease, or continue PA when experiencing CLBP. The primary aim was to explore the relationship between CLBP and PA and how this is influenced in different contexts (e.g., necessity of a task). METHODS: A mixed-methods survey was administered to 220 participants, including self-reported outcomes, and capturing responses to three distinct questions related to PA and CLBP. The data was analysed via a content analysis. RESULTS: The findings revealed that individuals with CLBP are most likely to modify PA in work-related contexts and least likely to cease it in the same setting. Housework emerged as the most common domain for cessation of PA, while work/study activities were predominantly continued. Reasons for these trends were typically task-based rather than health or enjoyment based and influenced by the perceived necessity of the task in question. CONCLUSION: The study highlights the role of occupational and educational settings in individual responses to CLBP. The findings also highlight a gap in public awareness regarding effective CLBP management strategies, emphasising the need for increased education and awareness programs.

Barriers and enablers to exercise adherence in people with nonspecific chronic low back pain: a systematic review of qualitative evidence.

ABSTRACT: Exercise is a first-line treatment for chronic low back pain (CLBP), reducing pain and disability in the short term. However, exercise benefits decrease over time, with a lack of long-term exercise adherence a potential reason for this. This study aimed to synthesize the perceptions and beliefs of individuals with CLBP and identify their barriers and enablers to exercise adherence. We searched CENTRAL, Embase, CINAHL, SPORTDiscus, PubMed, PsycINFO, and Scopus databases from inception to February 28, 2023, for qualitative studies that explored the factors influencing exercise adherence for people with CLBP. A hybrid approach combining thematic synthesis with the Theoretical Domains Framework was used to analyze data. We assessed methodological quality using the Critical Appraisal Skills Programme checklist and the level of confidence of the themes generated using the Confidence in the Evidence from Reviews of Qualitative Studies. Twenty-three papers (n = 21 studies) were included (n = 677 participants). Four main themes affected exercise adherence: (1) exercise, pain, and the body, (2) psychological factors, (3) social factors, and (4) external factors. These themes contained 16 subthemes that were predominantly both barriers and enablers to exercise adherence. The individual's experiences of barriers and enablers were most appropriately represented across a spectrum, where influencing factors could be a barrier or enabler to exercise adherence, and these could be specific to pre-exercise, during-exercise, and post-exercise situations. These findings may be used to improve exercise adherence and ultimately treatment outcomes in people with CLBP.

Are Exercise Interventions in Clinical Trials for Chronic Low Back Pain Dosed Appropriately to Meet the World Health Organization's Physical Activity Guidelines?

OBJECTIVE: This study aimed to estimate the proportion of exercise interventions tested in clinical trials of people with chronic low back pain (CLBP) that meet the World Health Organization's (WHO) physical activity guidelines. METHODS: A secondary analysis of the 2021 Cochrane review of exercise therapy for CLBP was performed. Data from each study were extracted by 1 reviewer and were checked by a second reviewer. Data extracted related to the frequency, duration and intensity of each exercise intervention, and the proportion of exercise interventions that met the WHO's physical activity guidelines (aerobic, muscle strengthening, or both) were determined. RESULTS: The 249 included trials comprised 426 exercise interventions. Few interventions reported an exercise type and dose consistent with the WHO guidelines (aerobic: 1.6%, muscle strengthening: 5.6%, both: 1.6%). Poor reporting of exercise intensity limited our ability to determine whether interventions met the guidelines. CONCLUSION: Few interventions tested in clinical trials for people with CLBP prescribe an exercise type and dose consistent with the WHO guidelines. Therefore, they do not appear sufficiently dosed to achieve broader health outcomes. Future trials should investigate the effect of WHO guideline-recommended exercise interventions on patient-reported outcomes (pain and disability) as well as health-related outcomes in people with CLBP. IMPACT: This exploratory analysis showed the lack of exercise interventions in the CLBP literature that meet the WHO's physical activity guidelines. With people in chronic pain groups, such as people with CLBP, being at higher risk for noncommunicable disease, it appears this is a key consideration for exercise practitioners when designing interventions for people with CLBP.

Are the attitudes and beliefs of Australian exercise-based practitioners associated with their use of, and confidence in, treatment modalities for people with chronic low back pain?

BACKGROUND: Practitioners' attitudes and beliefs towards chronic low back pain (CLBP) influence their clinical decision making, but few studies have investigated decision making outside the context of patient vignettes for a range of first- and second-line treatment options for CLBP, or in accredited exercise physiologists (AEPs). METHODS: Using an online survey, Australian AEPs and physiotherapists rated their use of different treatments for CLBP (exercise, education, manual therapy, cognitive behavioural therapy) and their confidence in these treatments for reducing pain and disability. Their biomedical and biopsychosocial beliefs were also assessed using the Pain and Attitudes Beliefs Scale for Physiotherapists. Differences between disciplines in treatment use and confidence were analysed using Mann-Whitney U tests and independent t-tests, respectively. Multiple linear regression was used to explore factors associated with treatment choices. RESULTS: Two-hundred thirty-three practitioners (n = 143 physiotherapists, n = 90 AEPs) completed the survey. Most practitioners were confident in treating CLBP, had a moderate-high level of confidence in the different treatments, and regularly used them in practice. Practitioners with higher biomedical beliefs had greater use of, and confidence in, specific exercise, manual therapy, and combined exercise and manual therapy. Practitioners with higher biopsychosocial beliefs were more confident in general exercise, cognitive behavioural therapy, pain education and combined exercise and pain education. CONCLUSION: Practitioner beliefs influence their use of, and confidence in different treatments for CLBP. These findings suggest a need for strategies to enhance biopsychosocial beliefs/reduce biomedical beliefs in Australian exercise-based practitioners.

Reductions in movement-associated fear are dependent upon graded exposure in chronic low back pain: An exploratory analysis of a modified 3-item fear hierarchy.

OBJECTIVE: To explore the effectiveness of a modified fear hierarchy on measuring improvements in movement-associated fear in chronic low back pain. METHODS: A modified 3-item fear hierarchy was created and implemented based on principles of graded exposure. This study was an exploratory analysis of the modified 3-item fear hierarchy from a larger clinical trial data set. Both groups received pain education and exercise, either bodyweight or strength training. Both groups performed item one on the hierarchy, the squat. Only the strength training group performed item 2, the deadlift. Neither group performed item 3, the overhead press. Analysis of Covariance and stepwise linear regression were used to explore results. RESULTS: Improvement in movement-associated fear was conditional upon graded exposure. Both groups improved in the squat movement (p ≤ 0.05), which both performed. Only the strength training group improved in the deadlift (p ≤ 0.01), and neither improved in the overhead press (p ≥ 0.05). CONCLUSION: Reductions in movement-associated fear are conditional upon graded exposure, based on the use of a novel modified 3-item fear hierarchy. Further research is needed to understand the utility of this tool in a patient-led approach to co-designing a graded exposure-based intervention.

Higher intensity exercise reduces disability more than lower intensity exercise in adults with chronic low back pain: A systematic review and meta-analysis.

BACKGROUND: Intensity is an important determinant of physiological adaptations and health benefits of exercise, but the role of exercise intensity on improving outcomes in people with chronic low back pain (CLBP) is unclear. This systematic review aimed to determine the effect of higher versus lower intensity exercise intensity on pain, disability, quality of life and adverse events in people with CLBP. METHODS: Six databases and four clinical trial registries were searched from inception to 21 December 2022, for randomised controlled trials that compared two or more exercise intensities in adults with CLBP. Data were analysed using random-effects meta-analysis for disability and synthesised narratively for pain, quality of life and adverse events due to limited studies. Risk of bias was assessed using the Cochrane tool and certainty of evidence was evaluated using Grading of Recommendations, Assessment, Development and Evaluations framework. RESULTS: Four trials (n = 214 participants, 84% male) reported across five studies were included. Higher intensity exercise reduced disability more than lower intensity exercise at end-treatment (SMD [95% CI] = -0.39 [-0.56 to -0.22]; very low certainty) but not at 6-month follow-up (SMD [95% CI] = -0.20 [-0.53 to 0.13]; very low certainty). Higher intensity exercise did not reliably improve pain and quality of life more than lower intensity exercise. Adverse events did not differ between exercise intensities. All studies were at high risk of bias. CONCLUSION: Based on very low certainty evidence from a limited number of studies, exercise intensity does not appear to meaningfully influence clinical outcomes in people with CLBP.

Are Improvements in Pain Neurophysiology Knowledge Following Pain Science Education Associated With Improved Outcomes in People With Chronic Pain?: A Systematic Review and Meta-analysis.

OBJECTIVE: This systematic review and meta-analysis aimed to determine the association between changes in patients' pain knowledge after pain science education (PSE) with treatment outcomes in people with chronic pain. METHODS: Six electronic databases and 2 clinical trial registries were searched from inception to September 15, 2021 for studies where participants received PSE and had their pain knowledge and clinical outcomes assessed before and after PSE. Meta-analyses were performed for pain intensity, kinesiophobia, and pain catastrophizing. Physical function and quality of life outcomes were synthesized narratively. Risk of bias was assessed using the Cochrane tool for nonrandomized studies and the quality of evidence was assessed using GRADE. RESULTS: Fourteen studies (n=1500 participants) were included. Meta-analyses revealed no significant associations between short-term (<12 wk) changes in pain neurophysiology knowledge with changes in pain intensity (n=1075, r=-0.01, 95% CI =-0.14 to 0.13, very low certainty), kinesiophobia (n=152, r=0.02, 95% CI =-0.27 to 0.24, very low certainty) and pain catastrophizing (n=976, r=-0.03, 95% CI=-0.18 to 0.11, low certainty). No significant associations were found between short-term changes in pain neurophysiology knowledge and physical function or quality of life either. DISCUSSION: These findings do not support a short-term association between improvements in pain neurophysiology knowledge and better treatment outcomes in people with chronic pain. Increased understanding of how PSE works, as well as better ways to measure it, may help clinicians deliver more targeted education to help patients reconceptualize pain and promote engagement in active treatment strategies (eg, exercise).

Data Informing Governing Body Resistance-Training Guidelines Exhibit Sex Bias: An Audit-Based Review.

The objective of this review was to examine the ratio of female and male participants utilised in data informing consensus statements and position stands in the field of resistance training (RT). In order to achieve this objective, we conducted an 'audit' style review. We accessed three databases: SPORTDiscus, MEDLINE and Google Scholar utilising the following search terms: resistance or strength training AND consensus statements or position statements/stands. Eligibility criteria included consensus statements and position stands for RT in youth, adults and older adults. In this paper we have used the term 'female' to describe biological sex. Gender is a social construct and often describes roles and behaviours that society assigns to men or women. In this paper we have used the term 'women' to describe gender. Reference lists from each guideline were screened with the number of male and female participants extracted from each study. We also extracted data on the gender of the authors of the statements. We located 11 guidelines encompassing a total of 104,251,363 participants. Youth guidelines were comprised of 69% male participants. There were 287 studies that included both sexes, 205 male-only and 92 female-only studies. Adult guidelines were comprised of 70% male participants. There were 104 studies that included both sexes, 240 male-only and 44 female-only studies. Older adult guidelines were comprised of 54% female participants. There were 395 studies that included both sexes, 112 male-only and 83 female-only studies. Women authors comprised 13% of all authors of position stands and consensus statements. These results demonstrate an under-representation of females and women as both participants and as authors. It is imperative to ensure that data informing governing body guidelines and consensus statements are representative of the population they aim to inform. If this is not possible, guidelines should clearly state when their data and recommendations are based primarily upon one sex.

The effect of exercise engagement on low back disability at 12-months is mediated by pain and catastrophizing in a community sample of people with chronic low back pain.

Despite being a first-line treatment recommendation, there is uncertainly for how exercise helps people with chronic low back pain. We designed this study to examine how exercise might help people with chronic low back pain by following a large community sample for 1-year. Qualitative questionnaires and self-report measures were collected every 3-months for 1-year in 400 people with chronic low back pain. People were not provided any specific treatment advice as part of this study but were allowed to engage with any normal physical activity, treatment, or medication as part of their normal life. Exercise engagement was defined from inspection of participant qualitative responses, according to minimum acceptable levels of exercise that elicit symptom reduction. Multiple mediation analysis was performed to examine the effect of exercise engagement on disability through the proposed mediators (pain, fear, catastrophizing, depression, anxiety, self-efficacy). The significant effect of exercise engagement on reductions in disability at 6- and 12-months was explained through pain and catastrophizing. People with chronic low back pain who reported worsening of symptoms over the year had similar reporting of exercise throughout the 12-months to people who had improvements in disability. Exercise can reduce disability through the effect on pain and catastrophizing, but how this effect occurs (i.e., an active or passive component of exercise) is unclear.

Biomedical Beliefs Explain the Clinical Decisions Made by Exercise-Based Practitioners for People With Chronic Low Back Pain.

STUDY DESIGN: Cross-sectional survey. OBJECTIVE: This study surveyed the attitudes and beliefs of physiotherapists and accredited exercise physiologists (AEP) toward chronic low back pain (CLBP), in Australia. The objective of this study was to investigate the effect of biomedical and biopsychosocial attitudes and beliefs toward CLBP on clinical decision making in exercise-based practitioners. SUMMARY OF BACKGROUND DATA: The attitudes and beliefs of AEPs toward CLBP have not been studied. Literature regarding physiotherapists suggests a biomedical approach leading to more conservative treatment and on occasion, treatment going against practice guidelines. METHODS: Seventy five AEPs and 75 physiotherapists were surveyed using the pain attitudes and beliefs scale for physiotherapists, which consists of both a biomedical and biopsychosocial subscale. Clinical decision making was assessed using two patient vignettes. RESULTS: AEPs held higher biomedical beliefs compared with physiotherapists. No between-group differences were observed on the biopsychosocial subscale. Indeed, biomedical attitudes and beliefs did explain clinical decision making with higher scores reflecting a more conservative approach. However, biomedical beliefs influenced decision making regardless of profession. CONCLUSION: Biomedical attitudes and beliefs regarding CLBP influence clinical decision making in exercise-based practitioners, regardless of profession. AEPs reported higher biomedical scores, suggesting more frequent choice of conservative care. Thus, patients may receive inconsistent care and advice from practitioners within the same field. Based on clinical practice guidelines and the positive associations on clinical decision making of the biopsychosocial model, it is necessary to understand how best to provide exercise-based practitioners with education on how to apply a biopsychosocial approach to CLBP.Level of Evidence: 3.

The Moderating Effect of Treatment Engagement on Fear-avoidance Beliefs in People With Chronic Low Back Pain.

OBJECTIVES: The fear-avoidance model (FAM) is used to explain pain-related disability and design targeted interventions for people with chronic low back pain. While treatment engagement is critical, it is unknown how treatment moderates the FAM. METHODS: This study examined whether pathways within the FAM were moderated by treatment engagement in 508 people with chronic low back pain. Measures of disability, pain, fear, catastrophizing, anxiety, depression, and self-efficacy were collected through self-report, and descriptors of treatment engaged within the last month (physical activity type, medication, allied and medical health practitioner). Moderated mediation analyses were performed to examine the conditional effect of treatment engagement on fear-avoidance pathways. RESULTS: The conditional effect of anxiety on disability was only significant for people who did not report any treatment engagement in the last month (B=1.03, 95% confidence interval: 0.53-1.53, P<0.001). The effect of depression increased for people reporting more different types of treatment in the last month (1 level of treatment increase, B=0.27, 95% confidence interval: 0.05-0.50, P=0.019). Conversely, greater treatment engagement had a positive influence on the mediating effect of self-efficacy. That is, the effect of pain on efficacy reduced with greater treatment engagement, with a concomitant increased effect of self-efficacy on disability. DISCUSSION: Clinicians should explore the history and rationale behind patient treatment seeking behavior to ensure this is not reinforcing the negative effects of depressive symptoms on pain-related disability.

Energetic lipid responses of larval oysters to ocean acidification.

Climate change will increase energetic demands on marine invertebrate larvae and make planktonic food more unpredictable. This study determined the impact of ocean acidification on larval energetics of the oysters Saccostrea glomerata and Crassostrea gigas. Larvae of both oysters were reared until the 9-day-old, umbonate stage under orthogonal combinations of ambient and elevated p CO 2 (340 and 856 µatm) and food was limited. Elevated p CO 2 reduced the survival, size and larval energetics, larvae of C. gigas being more resilient than S. glomerata. When larvae were fed, elevated p CO 2 reduced lipid levels across all lipid classes. When larvae were unfed elevated p CO 2 resulted in increased lipid levels and mortality. Ocean acidification and food will interact to limit larval energetics. Larvae of S. glomerata will be more impacted than C. gigas and this is of concern given their aquacultural status and ecological function.

Can prior exposure to stress enhance resilience to ocean warming in two oyster species?

Securing economically and ecologically significant molluscs, as our oceans warm due to climate change, is a global priority. South eastern Australia receives warm water in a strengthening East Australia Current and so resident species are vulnerable to elevated temperature and marine heat waves. This study tested whether prior exposure to elevated temperature can enhance resilience of oysters to ocean warming. Two Australian species, the flat oyster, Ostrea angasi, and the Sydney rock oyster, Saccostrea glomerata, were obtained as adults and "heat shocked" by exposure to a dose of warm water in the laboratory. Oysters were then transferred to elevated seawater temperature conditions where the thermal outfall from power generation was used as a proxy to investigate the impacts of ocean warming. Shell growth, condition index, lipid content and survival of flat oysters and condition of Sydney rock oysters were all significantly reduced by elevated seawater temperature in the field. Flat oysters grew faster than Sydney rock oysters at ambient temperature, but their growth and survival was more sensitive to elevated temperature. "Stress inoculation" by heat shock did little to ameliorate the negative effects of increased temperature, although the survival of heat-shocked flat oysters was greater than non-heat shocked oysters. Further investigations are required to determine if early exposure to heat stress can enhance resilience of oysters to ocean warming.