Performance of bull bars in pedestrian impact tests

Thirteen bull bars and the five models of vehicle were tested to measure their performance in pedestrian impact tests. Three tests were used in the assessment: two tests using an impactor representing the upper leg of an adult pedestrian, and a test with an impactor representing the head of a child. The headform impact and one of the upper legform impacts were with the top rail of the bull bar, and the second upper legform impact was with the bumper section of the bull bar. Equivalent locations on the vehicle that the bull bars were attached to were also tested. The tests were conducted at 30 km/h. Two rating systems were developed to summarise the results. The first rates the performance of the bull bars and the fronts of the vehicles according to the New Car Assessment Program consumer rating system used in Europe and Australia. The second system rates the performance of the bull bars relative to the front of the vehicle to which they are attached. Overall, steel bull bars are significantly more hazardous for a pedestrian in the event of a collision than the front of the vehicle, as are the aluminium/alloy bull bars, but to a lesser extent than the steel bull bars. Overall, the polymer bull bars slightly improve the safety of the front of the vehicle.. This study demonstrates the practicability of reporting the performance of bull bars in pedestrian impact tests. The system developed herein could form the basis of a consumer-oriented bull bar testing program.R.W.G. Anderson, A.L. van den Berg, G. Ponte, L.D. Streeter and A.J. McLeanhttp://casr.adelaide.edu.au/publications/researchreports

Magnetic Flux Density Sensor Analysis

Undergraduate Basi

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Plasma-based positron sources at EuPRAXIA

Abstract Plasma-based positron sources are attracting significant attention from the research community, thanks to their rather unique characteristics, which include broad energy tuneability and ultra-short duration, obtainable in a compact and relatively inexpensive setup. Here, we show a detailed numerical study of the positron beam characteristics obtainable at the dedicated user target areas proposed for the EuPRAXIA facility, the first plasma-based particle accelerator to be built as a user facility for applications. It will be shown that MeV-scale positron beams with unique properties for industrial and material science applications can be produced, alongside with GeV-scale positron beams suitable for fundamental science and accelerator physics.</jats:p

Plasma-based positron sources at EuPRAXIA

Plasma-based positron sources are attracting significant attention from the research community, thanks to their rather unique characteristics, which include broad energy tuneability and ultra-short duration, obtainable in a compact and relatively inexpensive setup. Here, we show a detailed numerical study of the positron beam characteristics obtainable at the dedicated user target areas proposed for the EuPRAXIA facility, the first plasma-based particle accelerator to be built as a user facility for applications. It will be shown that MeV-scale positron beams with unique properties for industrial and material science applications can be produced, alongside with GeV-scale positron beams suitable for fundamental science and accelerator physics. </p

Development and testing of production prototypes of a protective headband for car occupants

This report details the results of tests made on a headband designed to protect car occupants in a crash. The tests were performed in a manner such that the headband’s effectiveness could be compared with the requirements of the United States Federal Motor Vehicle Safety Standard 201. That standard requires a certain level of head protection for the occupants of the vehicle from the upper interior of the car. The standard stipulates that a free motion headform be fired against the interior components of the car at a speed of up to 24 km/h. The requirement is that a modified value of the Head Injury Criterion, HIC(d), be less than 1000. In these tests a free motion headform was launched at a beam that simulated a structure of a car’s interior. The stiffness of the beam was varied, and the headform was fired, first, without any protection, and second, with prototype headbands made of either 70 g/l EPP or 50 g/l EPP. By comparing the impacts in these configurations we found that the headband absorbed significant amounts of energy, reduced peak loads and kept the impact within acceptably safe limits as measured by the Head Injury Criterion. This study showed that the headband similar to that tested would offer significant head protection in frontal impacts. This could offer safety advantages to occupants of older vehicles who otherwise would not benefit from recent advances in occupant protection and also to occupants of more recent vehicles who might be seeking supplementary safety devices.Giulio Ponte, Robert Anderson, Jack McLean, Luke Streeter, Robert Tiller and Steve Hil

Visual Fatigue as a Predictor of Exercise Tolerance in Pediatric Athletes with Concussion

Background: Concussion patients may manifest changes in exercise tolerance (ET). Since the visual system is affected as well, investigating the relationship between ET and vision could prove useful in developing better rehabilitation strategies. Hypothesis/Purpose: To explore trends between ET and visual fatigue in pediatric concussion patients. Methods: A Retrospective chart review of 63 pediatric concussion patients ages 12-21 was collected from 11/05/21 to 6/10/21. Each patient completed a validated symptom-related questionnaire resulting in quantitative clinical profile (CP) score (0-89) and ocular profile subtype (OPS) score (0-3) with higher scores indicating worse symptoms. The OPS score is a weighted score based off of 5 vision focused questions regarding visual symptoms and visual fatigue. Each patient was also evaluated by a physician and classified into an active rehabilitation (AR) step (Step 1-5) based on exertional testing results using heart rate to establish exertional threshold at the visit. Patients were split up into low ET level (n=10) who could not exceed HR&lt;140bpm and high ET level (n=53) who exhibited vigorous to maximal intensities all tolerating HR&gt;140bpm. Near point convergence (NPC) and other objective exam markers were also evaluated at each patient visit. A paired two sample t-test compared the differences in their OPS and objective clinical data. Results: The low ET group averaged an OPS score of 1.84, CP score of 43.20, and a physician measured average NPC of 9.96 cm, while the high ET group averaged an OPS score of 0.68, CP score of 13.87, and a physician measured NPC of 9.06 cm (Table 1). T-test for the OPS and CP score revealed statistically significant differences (p value of 4.04E-05 and 3.49E-06 respectively) while the t-test for NPC had a p-value of 0.491. Conclusion: Visual fatigue as endorsed by the OPS score may be a critical subjective marker in predicting ET in pediatric athletes after concussion. Those tolerating vigorous or maximal exertion generally had significantly lower OPS scores, despite similar NPC findings in this small sample. Further studies are required to confirm this trend and how it may affect exertional rehabilitation strategies. [Table: see text] </jats:sec

Concussion Profile Screen Ocular Subtype Score and Objective Findings of Oculomotor Dysfunction in Pediatric Concussion Patients

Background: Visual abnormalities and oculomotor dysfunction are common findings in pediatric concussion patients. Not only are these symptoms reported by patients subjectively, but they can be measured objectively using clinical tools including oculomotor tracking (OMT) devices. Purpose: To identify trends between levels of subjective visual symptoms and objective oculomotor findings on OMT. Methods: Retrospective cohort of 65 patients (12-21 years old) from 11/05/20 to 6/10/21. Each visit, the concussion clinical profile (CP) screen was completed, which has a total score (0-89) and a weighted ocular subtype score (0-3) based on five vision focused questions in the screen. At the same visit, the OMT device (250 Hz video-eye tracker inside a headset) measured various biodata including microsaccade (MS) magnitude, vertical and horizontal saccadic latency. Near point convergence (NPC) was measured by a physician. Patients were classified into low grade (n=48) or high grade (n=17) using an ocular subtype score threshold of 1.5. A paired two sample t-test was used to compare both groups objective OMT data. Results: The low grade group had an average MS magnitude of 1.06 degrees, an average vertical saccadic latency of 217.49 ms, an average horizontal saccadic latency of 198.16 ms, and a physician measured NPC of 8.75 cm. The high grade group had an average MS magnitude of 1.21 degrees, an average vertical saccadic latency of 234.37 ms, an average horizontal saccadic latency of 202.24 ms, and a physician measured NPC of 13.82 cm ( Table 1 ). T-tests for MS magnitude and NPC revealed statistically significant differences between the two groups for both variables (p= 0.02 and p=0.003, respectively). The t-test for vertical latency had a p-value of 0.06. The low grade group had an average CP score of 9.3 while the high grade group had an average CP score of 43.7 with a statistically significant difference. Conclusion: Patients who report high grade visual symptoms on CP screen ocular subtype score show trends of higher MS magnitudes and saccadic latencies on OMT and higher NPC on exam. Furthermore, low grade patients report significantly lower CP scores compared to high grade patients suggesting visual abnormalities play a central role in overall symptom burden. Further studies are needed to confirm this trend and to evaluate the role of vision on the overall clinical picture of pediatric concussion patients. [Table: see text] </jats:sec