Injury severity of pedestrian crashes in Singapore

Singapore is a highly urbanized city-state country where walking is an important mode of travel. Pedestrians form about 25% of road fatalities every year, making them one of the most vulnerable road user groups in Singapore. Engineering measures like provision of overhead pedestrian crossings and raised zebra crossings tend to address pedestrian safety in general, but there may be occasions where pedestrians are particularly vulnerable so that targeted interventions are more appropriate. The objective of this study is to identify factors and situations that affect the injury severity of pedestrians involved in traffic crashes. Six years of crash data from 2003 to 2008 containing around four thousands pedestrian crashes at roadway segments were analyzed. Injury severity of pedestrians—recorded as slight injury, major injury and fatal—were modeled as a function of roadway characteristics, traffic features, environmental factors and pedestrian demographics by an ordered probit model. Results suggest that the injury severity of pedestrians involved in crashes during night time is higher indicating that pedestrian visibility during night is a key issue in pedestrian safety. The likelihood of fatal or serious injuries is higher for crashes on roads with high speed limit, center and median lane of multi-lane roads, school zones, roads with two-way divided traffic type, and when pedestrians cross the roads. Elderly pedestrians appear to be involved in fatal and serious injury crashes more when they attempt to cross the road without using nearby crossing facilities. Specific countermeasures are recommended based on the findings of this study.

The increased risks of death and extra lengths of hospital and ICU stay from hospital-acquired bloodstream infections : a case-control study

Objectives Hospital-acquired bloodstream infections are known to increase the risk of death and prolong hospital stay, but precise estimates of these two important outcomes from well-designed studies are rare, particularly for non-intensive care unit (ICU) patients. We aimed to calculate accurate estimates, which are vital for estimating the economic costs of hospital-acquired bloodstream infections.

Acute hamstring strain injury in track and field athletes : a 3-year observational study at the Penn Relay Carnival

Purpose To observe the incidence rates of hamstring strain injuries (HSIs) across different competition levels and ages during the Penn Relays Carnival. Methods Over a 3-year period all injuries treated by the medical staff were recorded. The type of injury, anatomic location, event in which the injury occurred, competition level and demographic data were documented. Absolute and relative HSI (per 1000 participants) were determined and odds ratios (OR) were calculated between genders, competition levels and events. Results Throughout the study period 48,473 athletes registered to participate in the Penn Relays Carnival, with 118 HSIs treated by the medical team. High school females displayed lesser risk of HSI than high school males (OR = 0.55, p = 0.021), and masters athletes were more likely than high school (OR = 4.26, p < 0.001) and college (OR = 3.55, p = 0.001) level athletes to suffer a HSI. The 4x400m relay displayed a greater likelihood of HSI compared to the 4x100m relay (OR = 1.77, p = 0.008). Conclusions High school males and masters levels athletes are most likely to suffer HSI, and there is higher risk in 400m events compared to 100m events.

Neuromuscular hamstring function in response to intermittent running and previous injury

This thesis examined the impact of previous hamstring injury and fatigue on the function of the hamstring muscles and their neural control. The work established the role of neuromuscular inhibition after hamstring injury and involved the development of a new field testing device for eccentric hamstring strength, which is now in high demand in elite sport worldwide. David has four peer-reviewed publications from this doctoral work.

Comparative study on the protective effects of Yinchenhao Decoction against liver injury induced by alpha-naphthylisothiocyanate and carbon tetrachloride

OBJECTIVE: To optimize the animal model of liver injury that can properly represent the pathological characteristics of dampness-heat jaundice syndrome of traditional Chinese medicine. METHODS: The liver injury in the model rat was induced by alpha-naphthylisothiocyanate (ANIT) and carbon tetrachloride (CCl(4) ) respectively, and the effects of Yinchenhao Decoction (, YCHD), a proved effective Chinese medical formula for treating the dampness-heat jaundice syndrome in clinic, on the two liver injury models were evaluated by analyzing the serum level of alanine aminotransferase (ALT), asparate aminotransferase (AST), alkaline phosphatase (ALP), malondialchehyche (MDA), total bilirubin (T-BIL), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) as well as the ratio of liver weight to body weight. The experimental data were analyzed by principal component analytical method of pattern recognition. RESULTS: The ratio of liver weight to body weight was significantly elevated in the ANIT and CCl(4) groups when compared with that in the normal control (P<0.01). The contents of ALT and T-BIL were significantly higher in the ANIT group than in the normal control (P<0.05,P<0.01), and the levels of AST, ALT and ALP were significantly elevated in CCl(4) group relative to those in the normal control P<0.01). In the YCHD group, the increase in AST, ALT and ALP levels was significantly reduced (P<0.05, P<0.01), but with no significant increase in serum T-BIL. In the CCl(4) intoxicated group, the MDA content was significantly increased and SOD, GSH-PX activities decreased significantly compared with those in the normal control group, respectively (P<0.01). The increase in MDA induced by CCl(4) was significantly reduced by YCHD P<0.05). CONCLUSION: YCHD showed significant effects on preventing liver injury progression induced by CCl(4), and the closest or most suitable animal model for damp-heat jaundice syndrome may be the one induced by CCl(4).

Comparison between electrically-evoked and voluntary wrist movements on sensorimotor and prefrontal cortical activation : A multi-channel time domain fNIRS study

Neuromuscular electrical stimulation (NMES) has been consistently demonstrated to improve skeletal muscle function in neurological populations with movement disorders, such as poststroke and incomplete spinal cord injury (Vanderthommen and Duchateau, 2007). Recent research has documented that rapid, supraspinal central nervous system reorganisation/neuroplastic mechanisms are also implicated during NMES (Chipchase et al., 2011). Functional neuroimaging studies have shown NMES to activate a network of sub-cortical and cortical brain regions, including the sensorimotor (SMC) and prefrontal (PFC) cortex (Blickenstorfer et al., 2009; Han et al., 2003; Muthalib et al., 2012). A relationship between increase in SMC activation with increasing NMES current intensity up to motor threshold has been previously reported using functional MRI (Smith et al., 2003). However, since clinical neurorehabilitation programmes commonly utilise NMES current intensities above the motor threshold and up to the maximum tolerated current intensity (MTI), limited research has determined the cortical correlates of increasing NMES current intensity at or above MTI (Muthalib et al., 2012). In our previous study (Muthalib et al., 2012), we assessed contralateral PFC activation using 1-channel functional near infrared spectroscopy (fNIRS) during NMES of the elbow flexors by increasing current intensity from motor threshold to greater than MTI and showed a linear relationship between NMES current intensity and the level of PFC activation. However, the relationship between NMES current intensity and activation of the motor cortical network, including SMC and PFC, has not been clarified. Moreover, it is of scientific and clinical relevance to know how NMES affects the central nervous system, especially in comparison to voluntary (VOL) muscle activation. Therefore, the aim of this study was to utilise multi-channel time domain fNIRS to compare SMC and PFC activation between VOL and NMESevoked wrist extension movements.

Surveillance report on injury deaths in Shouguang, 1993-1997 [寿光市疾病监测点1993～1997年意外死亡报告]

In this rural population, injuries claimed 9% of all deaths and was the 4th cause of death. Injury mortality was much higher among men than that for women. The major injury causes were traffic accidents (39%) and suicide (38%). Traffic accidents were the first injury cause for men but suicide the first cause for women. Abstract in Chinese 为查明我市农村居民意外死亡情况，为制定相应控制措施提供参考，我们对寿光市疾病监测点１９９３～１９９７年的居民意外死亡资料进行了分析。死因分类按国际疾病分类（ＩＣＤ－９）标准，标化死亡率采用１９９０年全国标准人口构成计算。１９９３～１９９７年寿光市疾病...

Comparing outcomes of a school based injury prevention intervention for low-medium risk adolescents with high-risk adoelscents

High-risk adolescents are shown to jeopardise their future social and health functioning as well as placing themselves and others at immediate risk of harm. The challenge of “reaching” high-risk adolescents, who are often marginalised, is considerable. There is a positive relationship between age and risk taking behaviors during adolescence. This study examines outcomes (alcohol use, transport risk behaviors, violence) of a school based intervention (SPIY) by comparing low-medium risk adolescents with high-risk adolescents over a six month period.

An extracellular signal-regulated kinase 2 survival pathway mediates resistance of human mesothelioma cells to asbestos-induced injury

We hypothesized that normal human mesothelial cells acquire resistance to asbestos-induced toxicity via induction of one or more epidermal growth factor receptor (EGFR) - linked survival pathways (phosphoinositol-3-kinase/AKT/ mammalian target of rapamycin and extracellular signal - regulated kinase [ERK] 1/2) during simian virus 40 (SV40) transformation and carcinogenesis. Both isolated HKNM-2 mesothelial cells and a telomerase-immortalized mesothelial line (LP9/TERT-1) were more sensitive to crocidolite asbestos toxicity than an SV40 Tag-immortalized mesothelial line (MET5A) and malignant mesothelioma cell lines (HMESO and PPM Mill). Whereas increases in phosphorylation of AKT (pAKT) were observed in MET5A cells in response to asbestos, LP9/TERT-1 cells exhibited dose-related decreases in pAKT levels. Pretreatment with an EGFR phosphorylation or mitogen-activated protein kinase kinase 1/2 inhibitor abrogated asbestos-induced phosphorylated ERK (pERK) 1/2 levels in both LP9/TERT-1 and MET5A cells as well as increases in pAKT levels in MET5A cells. Transient transfection of small interfering RNAs targeting ERK1, ERK2, or AKT revealed that ERK1/2 pathways were involved in cell death by asbestos in both cell lines. Asbestos-resistant HMESO or PPM Mill cells with high endogenous levels of ERKs or AKT did not show dose-responsive increases in pERK1/ERK1, pERK2/ERK2, or pAKT/AKT levels by asbestos. However, small hairpin ERK2 stable cell lines created from both malignant mesothelioma lines were more sensitive to asbestos toxicity than shERK1 and shControl lines, and exhibited unique, tumor-specific changes in endogenous cell death - related gene expression. Our results suggest that EGFR phosphorylation is causally linkedto pERK and pAKT activation by asbestos in normal and SV40 Tag - immortalized human mesothelial cells. They also indicate that ERK2 plays a role in modulating asbestos toxicity by regulating genes critical to cell injury and survival that are differentially expressed in human mesotheliomas.

Development of an evidence-based framework to guide injury prevention interventions for off-road motorcyclists

There is little research on off-road motorcycle and all-terrain vehicle riders though injury levels are high. This thesis identified formal responsibility for monitoring injuries, targeting young male and recreational riders, promotion of family members as models, and controlled and accessible riding locations as ways to increase safety. These recommendations were based on analysis of Queensland hospitalisation records, rider personal reports and survey responses.

Brain-inspired sensor fusion for navigating robots

Current state of the art robot mapping and navigation systems produce impressive performance under a narrow range of robot platform, sensor and environmental conditions, in contrast to animals such as rats that produce “good enough” maps that enable them to function under an incredible range of situations. In this paper we present a rat-inspired featureless sensor-fusion system that assesses the usefulness of multiple sensor modalities based on their utility and coherence for place recognition, without knowledge as to the type of sensor. We demonstrate the system on a Pioneer robot in indoor and outdoor environments with abrupt lighting changes. Through dynamic weighting of the sensors, the system is able to perform correct place recognition and mapping where the static sensor weighting approach fails.

Development of a new signal processing diagnostic tool for vibration signals acquired in transient conditions

The diagnostics of mechanical components operating in transient conditions is still an open issue, in both research and industrial field. Indeed, the signal processing techniques developed to analyse stationary data are not applicable or are affected by a loss of effectiveness when applied to signal acquired in transient conditions. In this paper, a suitable and original signal processing tool (named EEMED), which can be used for mechanical component diagnostics in whatever operating condition and noise level, is developed exploiting some data-adaptive techniques such as Empirical Mode Decomposition (EMD), Minimum Entropy Deconvolution (MED) and the analytical approach of the Hilbert transform. The proposed tool is able to supply diagnostic information on the basis of experimental vibrations measured in transient conditions. The tool has been originally developed in order to detect localized faults on bearings installed in high speed train traction equipments and it is more effective to detect a fault in non-stationary conditions than signal processing tools based on spectral kurtosis or envelope analysis, which represent until now the landmark for bearings diagnostics.

Neutrophil oxidative burst is primed by supernatant from stored red cells : implications for Transfusion-Related Acute Lung Injury (TRALI)

Aim/Background: Transfusion-related acute lung injury (TRALI) is a potentially fatal adverse transfusion reaction. It is hypothesised to occur via a two-insult mechanism: the recipient’s underlying co-morbidity in addition to the transfusion of blood products activate neutrophils in the lung resulting in damaged endothelium and capillary leakage. Neutrophil activation may occur by antibody or non-antibody related mechanisms, with the length of storage of cellular blood products implicated in the latter. This study investigated non-antibody mediated priming and/or activation of neutrophil oxidative burst. Methods: A cytochrome C reduction assay was used to assess priming and activation of neutrophil oxidative burst by pooled supernatant (SN) from day 1 (D1; n=75) and day 42 (D42; n=113) packed red blood cells (PRBC). Pooled PRBC-SN were assessed in parallel with PAF (priming), fMLP (activating), PAF + fMLP (priming + activating) and buffer only (negative) controls. Cytochrome C reduction was measured over 30min at 37oC (inclusive of 10min priming). Neutrophil activation by PRBC-SN was assessed cf. buffer only and neutrophil priming by PRBC-SN was assessed by co-incubation with fMLP cf. fMLP alone. One-way ANOVA; Newman-Keuls post-test; p<0.05; n=10 independent assays. Results: Neither D1- nor D42- PRBC-SN alone activated neutrophil oxidative burst. In addition, D1-PRBC-SN did not prime fMLP-activated neutrophil oxidative burst. D42-PRBC-SN did, however, prime neutrophils for subsequent activation of oxidative burst by fMLP, the magnitude of response being similar to PAF (a known neutrophil priming agonist). Conclusion: These findings are consistent with the two-insult mechanism of TRALI. Factors released into the SN during PRBC storage contributed to neutrophil priming synergistically with other neutrophil stimulating agonists. This implicates PRBC storage duration as a key factor contributing to non-immune neutrophil activation in the development of TRALI in patients with pre-disposing inflammatory conditions.