Variation in mortality following hip fracture across the Asia Pacific region: Systematic review and proportional meta-analysis.

OBJECTIVE: To determine country/region-specific mortality (in-hospital, 30-day and 1-year) following hip fracture across the Asia Pacific region. METHODS: Five databases MEDLINE, PUBMED, EMBASE, Web of Science and the Cochrane Library were searched to identify studies that reported mortality following hospitalisation for low-trauma hip fracture in adults aged ≥50 years with data from 2010 to 30 September 2021. There were no restrictions on study design or language. Pooled mortality estimates for countries/regions with ≥2 studies were calculated using random-effects models. RESULTS: In total 244 studies were included in the meta-analysis. 123 studies (1,382,810 patients, 13 countries/regions) reported in-hospital mortality which ranged from 1.4 % in Japan [95 %CI 1.2-1.7], Singapore [95 %CI 1.0-1.6], China [95 %CI 0.8-2.3] and Hong Kong SAR [95 %CI 0.8-2.6] to 5.5 % [95 %CI 4.1-7.2] in New Zealand. 92 studies (628,450 patients, 13 countries/regions) reported 30-day mortality which ranged from 1.2 % in Japan [95 %CI 0.9-1.5] and Thailand [95 %CI 0.7-2.0] to 7.4 % [95 %CI 7.0-7.8] in Australia. 142 studies (1,139,752 patients, 14 countries/regions) reported 1-year mortality which ranged from 10.8 % [95 %CI 9.6-12.1] in Singapore to 23.3 % [95 %CI 22.3-24.5] in Australia and 23.8 % in New Zealand. CONCLUSION: There is substantial variation in mortality across the Asia Pacific region. Short-term mortality rates in Asian countries, notably Japan and Singapore, are up to four-fold lower than for Australia and New Zealand. This difference, although less marked, is sustained at 1-year with a two-fold lower mortality rate in Asia. This meta-analysis is the first to delineate these differences, further studies are required to understand the reasons for this variation.

A general swimming response in exhausted obligate swimming fish.

Marine organisms normally swim at elevated speeds relative to cruising speeds only during strenuous activity, such as predation or escape. We measured swimming speeds of 29 ram ventilating sharks from 10 species and of three Atlantic bluefin tunas immediately after exhaustive exercise (fighting a capture by hook-and-line) and unexpectedly found all individuals exhibited a uniform mechanical response, with swimming speed initially two times higher than the cruising speeds reached approximately 6 h later. We hypothesized that elevated swimming behaviour is a means to increase energetic demand and drive the removal of lactate accumulated during capture via oxidation. To explore this hypothesis, we estimated the mechanical work that must have been spent by an animal to elevate its swim speed and then showed that the amount of lactate that could have been oxidized to fuel it comprises a significant portion of the amount of lactate normally observed in fishes after exhaustive exercise. An estimate for the full energetic cost of the catch-and-release event ensued.

The utility of bioenergetics modelling in quantifying predation rates of marine apex predators: Ecological and fisheries implications.

Predators play a crucial role in the structure and function of ecosystems. However, the magnitude of this role is often unclear, particularly for large marine predators, as predation rates are difficult to measure directly. If relevant biotic and abiotic parameters can be obtained, then bioenergetics modelling offers an alternative approach to estimating predation rates, and can provide new insights into ecological processes. We integrate demographic and ecological data for a marine apex predator, the broadnose sevengill shark Notorynchus cepedianus, with energetics data from the literature, to construct a bioenergetics model to quantify predation rates on key fisheries species in Norfolk Bay, Australia. We account for the uncertainty in model parameters by incorporating parameter confidence through Monte Carlo simulations and running alternative variants of the model. Model and parameter variants provide alternative estimates of predation rates. Our simplest model estimates that ca. 1130 ± 137 N. cepedianus individuals consume 11,379 (95% CI: 11,111-11,648) gummy sharks Mustelus antarcticus (~21 tonnes) over a 36-week period in Norfolk Bay, which represents a considerable contribution to total predation mortality on this key fishery species. This study demonstrates how the integration of ecology and fisheries science can provide information for ecosystem and fisheries management.

Feeding requirements of white sharks may be higher than originally thought.

Quantifying the energy requirements of animals in nature is critical for understanding physiological, behavioural, and ecosystem ecology; however, for difficult-to-study species such as large sharks, prey intake rates are largely unknown. Here, we use metabolic rates derived from swimming speed estimates to suggest that feeding requirements of the world's largest predatory fish, the white shark (Carcharodon carcharias), are several times higher than previously proposed. Further, our estimates of feeding frequency identify a clear benefit in seasonal selection of pinniped colonies - a white shark foraging strategy seen across much of their range.