Mortality following hip arthroplasty—inappropriate use of National Joint Registry (NJR) data

Mortality following hip arthroplasty is affected by a large number of confounding variables each of which must be considered to enable valid interpretation. Relevant variables available from the 2011 NJR data set were included in the Cox model. Mortality rates in hip arthroplasty patients were lower than in the age-matched population across all hip types. Age at surgery, ASA grade, diagnosis, gender, provider type, hip type and lead surgeon grade all had a significant effect on mortality. Schemper's statistic showed that only 18.98% of the variation in mortality was explained by the variables available in the NJR data set. It is inappropriate to use NJR data to study an outcome affected by a multitude of confounding variables when these cannot be adequately accounted for in the available data set.

Calculate excess mortality during heatwaves using Hilbert-Huang transform algorithm

Background Heatwaves could cause the population excess death numbers to be ranged from tens to thousands within a couple of weeks in a local area. An excess mortality due to a special event (e.g., a heatwave or an epidemic outbreak) is estimated by subtracting the mortality figure under ‘normal’ conditions from the historical daily mortality records. The calculation of the excess mortality is a scientific challenge because of the stochastic temporal pattern of the daily mortality data which is characterised by (a) the long-term changing mean levels (i.e., non-stationarity); (b) the non-linear temperature-mortality association. The Hilbert-Huang Transform (HHT) algorithm is a novel method originally developed for analysing the non-linear and non-stationary time series data in the field of signal processing, however, it has not been applied in public health research. This paper aimed to demonstrate the applicability and strength of the HHT algorithm in analysing health data. Methods Special R functions were developed to implement the HHT algorithm to decompose the daily mortality time series into trend and non-trend components in terms of the underlying physical mechanism. The excess mortality is calculated directly from the resulting non-trend component series. Results The Brisbane (Queensland, Australia) and the Chicago (United States) daily mortality time series data were utilized for calculating the excess mortality associated with heatwaves. The HHT algorithm estimated 62 excess deaths related to the February 2004 Brisbane heatwave. To calculate the excess mortality associated with the July 1995 Chicago heatwave, the HHT algorithm needed to handle the mode mixing issue. The HHT algorithm estimated 510 excess deaths for the 1995 Chicago heatwave event. To exemplify potential applications, the HHT decomposition results were used as the input data for a subsequent regression analysis, using the Brisbane data, to investigate the association between excess mortality and different risk factors. Conclusions The HHT algorithm is a novel and powerful analytical tool in time series data analysis. It has a real potential to have a wide range of applications in public health research because of its ability to decompose a nonlinear and non-stationary time series into trend and non-trend components consistently and efficiently.

Discerning the timing and cause of historical mortality events in modern Porites from the Great Barrier Reef

The life history strategies of massive Porites corals make them a valuable resource not only as key providers of reef structure, but also as recorders of past environmental change. Yet recent documented evidence of an unprecedented increase in the frequency of mortality in Porites warrants investigation into the history of mortality and associated drivers. To achieve this, both an accurate chronology and an understanding of the life history strategies of Porites are necessary. Sixty-two individual Uranium–Thorium (U–Th) dates from 50 dead massive Porites colonies from the central inshore region of the Great Barrier Reef (GBR) revealed the timing of mortality to have occurred predominantly over two main periods from 1989.2 ± 4.1 to 2001.4 ± 4.1, and from 2006.4 ± 1.8 to 2008.4 ± 2.2 A.D., with a small number of colonies dating earlier. Overall, the peak ages of mortality are significantly correlated with maximum sea-surface temperature anomalies. Despite potential sampling bias, the frequency of mortality increased dramatically post-1980. These observations are similar to the results reported for the Southern South China Sea. High resolution measurements of Sr/Ca and Mg/Ca obtained from a well preserved sample that died in 1994.6 ± 2.3 revealed that the time of death occurred at the peak of sea surface temperatures (SST) during the austral summer. In contrast, Sr/Ca and Mg/Ca analysis in two colonies dated to 2006.9 ± 3.0 and 2008.3 ± 2.0, suggest that both died after the austral winter. An increase in Sr/Ca ratios and the presence of low Mg-calcite cements (as determined by SEM and elemental ratio analysis) in one of the colonies was attributed to stressful conditions that may have persisted for some time prior to mortality. For both colonies, however, the timing of mortality coincides with the 4th and 6th largest flood events reported for the Burdekin River in the past 60 years, implying that factors associated with terrestrial runoff may have been responsible for mortality. Our results show that a combination of U–Th and elemental ratio geochemistry can potentially be used to precisely and accurately determine the timing and season of mortality in modern massive Porites corals. For reefs where long-term monitoring data are absent, the ability to reconstruct historical events in coral communities may prove useful to reef managers by providing some baseline knowledge on disturbance history and associated drivers.

Engendering the responsibility to protect : women and the prevention of mass atrocities

This article explores the relationship between the Responsibility to Protect (R2P) and the pursuit of the so-called ‘Women, Peace and Security’ (WPS) agenda at the UN. We ask whether the two agendas should continue to be pursued separately or whether each can make a useful contribution to the other. We argue that while the history of R2P has not included language that deliberately evokes the protection of women and the promotion of gender in preventing genocide and mass atrocities, this does not preclude the R2P and WPS agendas becoming mutually reinforcing. The article identifies cross-cutting areas where the two agendas may be leveraged for the UN and member states to address the concerns of women as both actors in need of protection and active agents in preventing and responding to genocide and mass atrocities, namely in the areas of early warning.

Advanced mass spectrometry-based multi-omics technologies for exploring the pathogenesis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the primary hepatic malignancies and is the third most common cause of cancer related death worldwide. Although a wealth of knowledge has been gained concerning the initiation and progression of HCC over the last half century, efforts to improve our understanding of its pathogenesis at a molecular level are still greatly needed, to enable clinicians to enhance the standards of the current diagnosis and treatment of HCC. In the post-genome era, advanced mass spectrometry driven multi-omics technologies (e.g., profiling of DNA damage adducts, RNA modification profiling, proteomics, and metabolomics) stand at the interface between chemistry and biology, and have yielded valuable outcomes from the study of a diversity of complicated diseases. Particularly, these technologies are being broadly used to dissect various biological aspects of HCC with the purpose of biomarker discovery, interrogating pathogenesis as well as for therapeutic discovery. This proof of knowledge-based critical review aims at exploring the selected applications of those defined omics technologies in the HCC niche with an emphasis on translational applications driven by advanced mass spectrometry, toward the specific clinical use for HCC patients. This approach will enable the biomedical community, through both basic research and the clinical sciences, to enhance the applicability of mass spectrometry-based omics technologies in dissecting the pathogenesis of HCC and could lead to novel therapeutic discoveries for HCC.

The importance of science fiction and other STEM-related mass media in young people’s decisions to enrol in university STEM courses

This paper presents Australian results from the Interests and Recruitment in Science (IRIS) study with respect to the influence of STEM-related mass media, including science fiction, on students’ decisions to enrol in university STEM courses. The study found that across the full cohort (N=2999), students tended to attribute far greater influence to science-related documentaries/channels such as Life on Earth and the Discovery Channel, etc. than to science-fiction movies or STEM-related TV dramas. Males were more inclined than females to consider science fiction/fantasy books and films and popular science books/magazines as having been important in their decisions. Students taking physics/astronomy tended to rate the importance of science fiction/fantasy books and films higher than students in other courses. The implications of these results for our understanding of influences on STEM enrolments are discussed.

Determinants and measurement of lean body mass in Indian adults

Indians tend to have lower lean body mass than other ethnic groups which increases the risk of chronic diseases. Three complementary studies included in this thesis advanced knowledge on determinants of lean body mass in Indians and the techniques to measure it. The first study examined the determinants of lean body mass in young Indian adults and highlighted the importance of diet and physical activity for development of lean body mass. This study has important implications for policy on prevention of chronic diseases in India. The other two studies helped refinement of the techniques of lean body mass measurement and are expected to facilitate future research in this area. The thesis is presented in the form of publications in high ranking journals.

Parent's socio-economic status and social support as risks for child mortality : consideration of health equity in The Gambia

A matched case-control study of mortality to children under age five was conducted to consider associations with parents' socio-economic status and social support in the Farafenni Demographic Surveillance Site (DSS). Cases and controls were selected from Farafenni DSS, matched on date of birth, and parents were interviewed about personal resources and social networks. Parents with the lowest personal socio-economic status and social support were identified. Multivariate multinomial regression was used to consider whether the children of these parents were at increased risk of either infant or 1-4 mortality, in separate models using either parents' characteristics. There was no benefit found for higher SES or better social support with respect to child mortality. Children of fathers who had the poorest social support had lower 1-4 mortality risk (OR=0.52, p=0.037). Given that socio-economic status was not associated with child mortality, it seems unlikely that the explanation for the link between father's social support and mortality is linked to resource availability. Explanations for the risk effect of father's social ties may lie in decision-making around health maintenance and health care for children.

In-hospital mortality rates after a cemented femoral component for displaced neck of femur fractures

Aim This prospective cohort study investigated whether the use of preoperative anticoagulants is an independent risk factor for the outcomes of surgical treatment of patients with a neck of femur fracture. Methods Data was obtained from a prospectively collected database. All patients admitted for a neck of femur fracture between Nov 2010 and Oct 2011 were included. This resulted in three hundred twenty-eight patients with 330 neck of femur fractures. Four groups were defined; patients preoperatively (i) on aspirin (n = 105); (ii) on clopidogrel (n = 28); (iii) on warfarin (n = 30), and; (iv) without any anticoagulation history (n = 167, the control group). The non-warfarin group included the aspirin group, clopidogrel group and the control group. Primary outcome was the in-hospital mortality. Secondary outcomes were the postoperative complications, return to theatre and length of stay. Results Thirteen in-hospital deaths were identified, 4 deaths in the aspirin group, 1 death in the clopidogrel group, 2 deaths in the warfarin group and 6 deaths in the control group. No significant difference in the mortality rates was found between the different groups. Also in the secondary outcomes, no significant difference was found between the four groups. A trend to a higher wound complication rate for the warfarin group was detected. Conclusion The use of clopidrogel or aspirin pre operatively is not an influence on short term patient outcome for patients with a neck of femur fracture. Surgical procedures should not be delayed to reverse their influence.

Assessment of the mortality displacement in temperature-related deaths in Brisbane, Australia

This thesis is a population-based ecological study designed to investigate the issue of mortality displacement (or "harvesting" effect) in the assessment of temperature-related deaths in Brisbane, Australia. It examines the temperature impacts on mortality, and assesses the harvesting effects on the temperature–related deaths. This study contributes to the knowledge base of understanding the temperature-mortality relationship and assists in formulating and evaluating public health intervention strategies within the context of climate change.