Aquatic fauna and flora surveys at the Lennox Weir, Busselton

Water Corporation proposes to undertake infrastructure works on the Lennox Weir, near Busselton, Western Australia. Due to the potential impact on aquatic fauna and flora associated with the proposed works, the Water Corporation engaged the Harry Butler Institute (Murdoch University) to carry out a desktop review and field survey for flora and fauna upstream and downstream of the structure. The study aimed to provide an assessment of the likely impacts of the proposed works on prevailing native species, and develop recommendations to mitigate any potential identified impacts. A desktop assessment of the fauna and flora communities around Lennox Weir was initially conducted. Subsequently, standardised surveys were conducted for flora and fauna at Lennox Weir in August 2019, again in October 2019 for flora, and finally in January (into early February) 2020 for flora and fauna. The proposed replacement or removal of the Lennox Weir was found to have a moderate to high risk of localised impacts on freshwater fishes upstream; based on the four storm surge scenarios modelled by GHD (2018a). Contrary to recent impact assessment by GHD (2018b), high abundances of native fishes were found to be present upstream of the weir in summer, which could be impacted by sudden increases in salinity predicted by the storm surge modelling. The upstream spatial extent of this impact would depend on the storm surge scenario. However, under all scenarios freshwater fishes are likely to be impacted (including potential high levels of mortality) in zone 2 (from the weir to 500m upstream) and a proportion of zone 3 (between 500‐ 1100m upstream). However, while the known acute salinity tolerances of resident native fishes would be exceeded in those sections, the behavioural responses of the fishes may help to partially or totally) mitigate the impacts. This could include moving upstream away from the incoming saline water, or more likely, utilising a freshwater lens that may be present. However, the hydrological modelling by GHD (2018a) did not consider or model the potential for a freshwater surface layer to form. Additional modelling would be required to better predict whether these factors could occur to mitigate the impacts on freshwater fishes. The assessment also revealed that the Threatened (EPBC Act 1999) Carter’s Freshwater Mussel Westralunio carteri was present in the Lennox River from just upstream of the weir to at least the Vasse‐Yallingup Siding Rd. However, its relative abundance increased significantly with distance upstream of the weir and the lowest abundances were found in zones 2 and 3; the sites predicted to be most affected by increased salinity under the modelled storm surge scenarios. As concluded by the previous impact assessment (GHD 2018b), the risk to the species of the increase in salinity would be high to moderate in zones 2 and 3 with residual salinity after 24 hours under all four storm surge scenarios projected to exceed its known tolerances in zone 2 and a proportion of zone 3. However, there remains uncertainty of this impact owing to the fact that modelling of residual salinity was only undertaken for a 24 hour period. Previous acute salinity trials of the species revealed the initial deaths occurred after 10 days at 8 mg/l, highest salinity level tested. The impact on the species in terms of mortality would therefore likely depend on the longer‐term residual salinity levels following storm surges. The impact on the South‐west Snake Neck Turtle Chelodina colliei upstream of the Lennox Weir was assessed as low in the current study. While there may be a short‐term decline in abundances of salt‐intolerant freshwater fishes and invertebrates associated with the modelled storm surges, there were high abundances of alternative prey items present particularly the Blue‐spot Goby Pseodogobius olorum and South‐west Glass Shrimp Palaemon australis. While the Smooth Marron Cherax cainii was not detected during the current sampling in the impacted reach (only visually observed upstream at the Vasse‐Yallingup Siding Rd), additional anecdotal information from the landholder suggested they may be present in low abundances within zone 3. If present, those individuals would have a high risk of impact under all scenarios and would likely walk out of the river to avoid the salinity. The Lennox Weir survey area occurs within a Conservation Category Wetland area. Upstream and downstream vegetation differed in terms of community structure and condition. The upstream vegetation is an example of very old remnant riparian vegetation and included poorly represented community types. The vegetation provides habitat for the Critically Endangered Western Ringtail Possum, with extensive scat noted throughout the survey area. The P4 species Eucalyptus rudis subsp. cratyantha occurs in riparian vegetation upstream and downstream and on adjacent land north‐east of the weir. Changes to the salinity regime associated with altering the function of the weir are likely to impact this vegetation

The effect of carbohydrate dose and timing on timed effort and time to exhaustion within a simulated cycle race in male professional cyclists

A key performance limitation affecting professional endurance cycling is carbohydrate storage and utilisation (Pöchmüller, Schwingshack, Colombani & Hoffmann, 2016, Journal of the International Society of Sports Nutrition, 13). Muscle glycogen stores alone are inefficient at maintaining optimal blood glucose levels beyond two hours of exercise; consequently, exogenous CHO is commonly used to counteract this (Jeukendrup, 2011, Journal of Sports Sciences, 21, 91-99). High concentrations of CHO can cause drops in blood glucose, excessive glycogen utilisation and gastrointestinal discomfort (GID) (Jeukendrup, 2011). Therefore, the aim of this study was to determine if frequent, smaller CHO feedings would be preferable to large, bolus CHO feedings on time trial cycling performance. With institutional ethics approval, 5 professional cyclists completed a 4h simulated cycle ride with 3 timed efforts in a randomised, cross-over, double blind design study. Each timed effort occurred in the last 10 min of each hour (TE1, TE2, TE3); participants were asked to cycle with maximum effort for this time. There was also a final effort at the end of the 4th hour to replicate a sprint finish. This was measured as time to exhaustion (TTE). Two interventions were used; a frequent feed (F) where participants drank 20g maltodextrin in 300ml flavoured water solution 3 times per hour and a bolus feed (B) where participants drank 60g maltodextrin solution once per hour. Heart rate, power output, GID, perceived exertion (RPE), blood lactate and blood glucose were recorded before and after TE1, TE2, TE3 and TTE. Wilcoxen signed rank test and Cohen’s D was performed to study differences between interventions and effect sizes.In the F intervention, average watts were significantly higher at TE2 (P<0.05 d=0.75) and TE3 (P<0.05 d=1.21) and the RPE was lower TE1 (P≥0.05 d=1.12), TE2 (P<0.05, d=1.12) and TTE (P≥0.05 d=1.12) compared to B. There was no significant difference between any other variables. The results suggest that despite power output being higher, RPE was lower in the F intervention. Gut absorption of CHO is limited to 1g/h (Jeukendrup, 2011), which may help explain these findings. This is one of the first studies to look at concentration and timing of CHO consumption in endurance cycling. Regular feeds of 20g CHO may be more beneficial on power output and RPE in endurance cycling compared to hourly 60g feeds

Recovery following a marathon: a comparison of cold water immersion, whole body cryotherapy and a placebo control

Purpose: Cryotherapy is an increasingly popular recovery strategy used in an attempt to attenuate the negative impact of strenuous physical activity on subsequent exercise. Therefore, this study aimed to assess the effects of whole body cryotherapy (WBC) and cold water immersion (CWI) on markers of recovery following a marathon. Methods: Thirty-one endurance trained males completed a marathon. Participants were randomly assigned to a CWI, WBC or placebo group. Perceptions of muscle soreness, training stress and markers of muscle function were recorded before the marathon and at 24 and 48 h post exercise. Blood samples were taken at baseline, post intervention and 24 and 48 h post intervention to assess inflammation and muscle damage. Results: WBC had a harmful effect on muscle function compared to CWI post marathon. WBC positively influenced perceptions of training stress compared to CWI. With the exception of C-reactive protein (CRP) at 24 and 48 h, neither cryotherapy intervention positively influenced blood borne markers of inflammation or structural damage compared to placebo. Conclusion: The findings show WBC has a negative impact on muscle function, perceptions of soreness and a number of blood parameters compared to CWI, contradicting the suggestion that WBC may be a superior recovery strategy. Further, cryotherapy is no more effective than a placebo intervention at improving functional recovery or perceptions of training stress following a marathon. These findings lend further evidence to suggest that treatment belief and the placebo effect may be largely responsible for the beneficial effects of cryotherapy on recovery following a marathon

A combination of cherry juice and cold water immersion does not enhance marathon recovery compared to either treatment in isolation: a randomized placebo-controlled trial

Purpose: Cherry juice (CJ) and cold water immersion (CWI) are both effective recovery strategies following strenuous endurance exercise. However, athletes routinely combine recovery interventions and less is known about the impact of a combined CJ and CWI protocol. Therefore, this study investigated the effects of combining CWI and CJ (a “cocktail” (CT)) on inflammation and muscle damage following a marathon. Methods: A total 39 endurance trained males were randomly assigned to a placebo (PL), CWI, CJ, or CT group before completing a trail marathon run. Muscle damage (creatine kinase (CK)), muscle function (maximal voluntary isometric contraction (MVIC)), and inflammation (interleukin-6 (IL-6); C-reactive protein (CRP)) were measured at baseline, immediately after marathon (only IL-6), 24 h, and 48 h after marathon. Results: There were no statistically significant differences between groups and no group × time interaction effects for any of the dependent variables. Confidence intervals (CI) illustrated that CT had unclear effects on inflammation (IL-6; CRP) and MVIC, but may have increased CK to a greater extent than PL and CJ conditions. Conclusion: There is no evidence of an additive effect of CJ and CWI when the treatments are used in conjunction with each other. On the contrary, combining CJ and CWI may result in slightly increased circulating CK

The academic backbone: longitudinal continuities in educational achievement from secondary school and medical school to MRCP(UK) and the specialist register in UK medical students and doctors

Background: Selection of medical students in the UK is still largely based on prior academic achievement, although doubts have been expressed as to whether performance in earlier life is predictive of outcomes later in medical school or post-graduate education. This study analyses data from five longitudinal studies of UK medical students and doctors from the early 1970s until the early 2000s. Two of the studies used the AH5, a group test of general intelligence (that is, intellectual aptitude). Sex and ethnic differences were also analyzed in light of the changing demographics of medical students over the past decades. Methods: Data from five cohort studies were available: the Westminster Study (began clinical studies from 1975 to 1982), the 1980, 1985, and 1990 cohort studies (entered medical school in 1981, 1986, and 1991), and the University College London Medical School (UCLMS) Cohort Study (entered clinical studies in 2005 and 2006). Different studies had different outcome measures, but most had performance on basic medical sciences and clinical examinations at medical school, performance in Membership of the Royal Colleges of Physicians (MRCP(UK)) examinations, and being on the General Medical Council Specialist Register. Results: Correlation matrices and path analyses are presented. There were robust correlations across different years at medical school, and medical school performance also predicted MRCP(UK) performance and being on the GMC Specialist Register. A-levels correlated somewhat less with undergraduate and post-graduate performance, but there was restriction of range in entrants. General Certificate of Secondary Education (GCSE)/O-level results also predicted undergraduate and post-graduate outcomes, but less so than did A-level results, but there may be incremental validity for clinical and post-graduate performance. The AH5 had some significant correlations with outcome, but they were inconsistent. Sex and ethnicity also had predictive effects on measures of educational attainment, undergraduate, and post-graduate performance. Women performed better in assessments but were less likely to be on the Specialist Register. Non-white participants generally underperformed in undergraduate and post-graduate assessments, but were equally likely to be on the Specialist Register. There was a suggestion of smaller ethnicity effects in earlier studies. Conclusions: The existence of the Academic Backbone concept is strongly supported, with attainment at secondary school predicting performance in undergraduate and post-graduate medical assessments, and the effects spanning many years. The Academic Backbone is conceptualized in terms of the development of more sophisticated underlying structures of knowledge ('cognitive capital’ and 'medical capital’). The Academic Backbone provides strong support for using measures of educational attainment, particularly A-levels, in student selection

Evolution of spin in the intermediate polar CC sculptoris

We report on spin variations in the intermediate polar and cataclysmic variable CC Scl, as seen by the Transiting Exoplanet Survey Satellite (TESS). By studying both the spin period and its harmonic, we find that the spin has varied since it was first observed in 2011. We find the latest spin value for the source to be 389.473(6) s, equivalent to 0.00450779(7) d, 0.02 s shorter than the first value measured. A linear fit to these and intermediate data give a rate of change of spin (Ṗ) ∼ −4.26(2.66)× 10−11 and a characteristic time-scale τ ∼ 2.90 × 105 yr, in line with other known intermediate polars with varying spin. The spin profile of this source also matches theoretical spin profiles of high-inclination intermediate polars, and furthermore, appears to have changed in shape over a period of three years. Such ‘spin-up’ in an intermediate polar is considered to be from mass accretion on to the white dwarf (the primary), and we note the presence of dwarf nova eruptions in this source as being a possible catalyst of the variations

Well-being in residency training: a survey examining resident physician satisfaction both within and outside of residency training and mental health in Alberta

BACKGROUND: Despite the critical importance of well-being during residency training, only a few Canadian studies have examined stress in residency and none have examined well-being resources. No recent studies have reported any significant concerns with respect to perceived stress levels in residency. We investigated the level of perceived stress, mental health and understanding and need for well-being resources among resident physicians in training programs in Alberta, Canada. METHODS: A mail questionnaire was distributed to the entire resident membership of PARA during 2003 academic year. PARA represents each of the two medical schools in the province of Alberta. RESULTS: In total 415 (51 %) residents participated in the study. Thirty-four percent of residents who responded to the survey reported their life as being stressful. Females reported stress more frequently than males (40% vs. 27%, p < 0.02). Time pressure was reported as the number one factor contributing to stress (44% of males and 57% of females). A considerable proportion of residents would change their specialty program (14%) and even more would not pursue medicine (22%) if given the opportunity to relive their career. Up to 55% of residents reported experiencing intimidation and harassment. Intimidation and harassment was strongly related to gender (12% of males and 38% of females). Many residents (17%) rated their mental health as fair or poor. This was more than double the amount reported in the Canadian Community Health Survey from the province (8%) or the country (7%). Residents highly valued their colleagues (67%), program directors (60%) and external psychiatrist/psychologist (49%) as well-being resources. Over one third of residents wished to have a career counselor (39%) and financial counselor (38%). CONCLUSION: Many Albertan residents experience significant stressors and emotional and mental health problems. Some of which differ among genders. This study can serve as a basis for future resource application, research and advocacy for overall improvements to well-being during residency training

Accretion physics at high X-ray spectral resolution: New frontiers and game-changing science

Microcalorimeters have demonstrated success in delivering high spectral resolution, and have paved the path to revolutionary new science possibilities in the coming decade of X-ray astronomy. There are several research areas in compact object science that can only be addressed with energy resolution Delta(E)<~5 eV at photon energies of a few keV, corresponding to velocity resolution of <~a few hundred km/s, to be ushered in by microcalorimeters. Here, we review some of these outstanding questions, focusing on how the research landscape is set to be transformed (i) at the interface between accreting supermassive black holes and their host galaxies, (ii) in unravelling the structures of accretion environments, (iii) in resolving long-standing issues on the origins of energy and matter feedback, and (iv) to test mass-scaled unification of accretion and feedback. The need to learn lessons from Hitomi and to make improvements in laboratory atomic data precision as well as plasma modeling are highlighted.Comment: To appear in Nature Astronomy as a review. Author version, before final editorial and style revision