scholarly journals Potential of Soft-Shelled Rugby Headgear to Reduce Linear Impact Accelerations

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Nick Draper ◽  
Natalia Kabaliuk ◽  
Danyon Stitt ◽  
Keith Alexander
Keyword(s):  
Linear Acceleration ◽  
Side Impact ◽  
Drop Height ◽  
Test Rig ◽  
Head Injury Criterion ◽  
Side Impacts ◽  
Hybrid Iii ◽  
Impact Attenuation ◽  
Post Hoc ◽  
Better Than

The purpose of this study was to examine the potential of soft-shelled rugby headgear to reduce linear impact accelerations. A hybrid III head form instrumented with a 3-axis accelerometer was used to assess headgear performance on a drop test rig. Six headgear units were examined in this study: Canterbury Clothing Company (CCC) Ventilator, Kukri, 2nd Skull, N-Pro, and two Gamebreaker headgear units of different sizes (headgears 1–6, respectively). Drop heights were 238, 300, 610, and 912 mm with 5 orientations at each height (forehead, front boss, rear, rear boss, and side). Impact severity was quantified using peak linear acceleration (PLA) and head injury criterion (HIC). All headgear was tested in comparison to a no headgear condition (for all heights). Compared to the no headgear condition, all headgear significantly reduced PLA and HIC at 238 mm (16.2–45.3% PLA and 29.2–62.7% HIC reduction; P < 0.0005 , ηp2 = 0.987–0.991). Headgear impact attenuation lowered significantly as the drop height increased (32.4–5.6% PLA and 50.9–11.7% HIC reduction at 912 mm). There were no significant differences in PLA or HIC reduction between headgear units 1–3. Post hoc testing indicated that headgear units 4–6 significantly outperformed headgear units 1–3 and additionally headgear units 5 and 6 significantly outperformed headgear 4 ( P < 0.05 ). The lowest reduction PLA and HIC was for impacts rear orientation for headgear units 1–4 (3.3 ± 3.6%–11 ± 5.8%). In contrast, headgear units 5 and 6 significantly outperformed all other headgear in this orientation ( P < 0.0005 , ηp2 = 0.982–0.990). Side impacts showed the greatest reduction in PLA and HIC for all headgear. All headgear units tested demonstrated some degree of reduction in PLA and HIC from a linear impact; however, units 4–6 performed significantly better than headgear units 1–3.

scholarly journals Forensic Engineering Analysis Of Head Impacts Within A Vehicle Subject To Side Impact

2005 ◽  
Vol 22 (1) ◽  
Author(s):  
Laura L. Liptai
Keyword(s):  
Motor Vehicle ◽  
Side Impact ◽  
Engineering Analysis ◽  
Motor Vehicle Collisions ◽  
Vehicle Interior ◽  
Vehicle Collisions ◽  
Head Impacts ◽  
Head Injury Criterion ◽  
Side Impacts ◽  
Forensic Engineering

Asymmetric Design Of Seatbelts Does Not Limit Potentially Injurious Contact With Vehicle Interior In Opposite Side Motor Vehicle Collisions. In Opposite Side Impacts, Of Approximately 65 To 70 Degrees, The Lap And Shoulder Restraint Functions Less Effectively. At These Angles, With A Change In Velocity Of Greater Than Or Equal To 20 Mph, The Head Injury Criterion (Hic) May Exceed Tolerance When The Occupants Head Impacts Unyielding Structural Surfaces Within The Vehicle. Biomedical Engineering Analysis Should Be Conducted To Determine The Likelihood Of Sustaining Brain Trauma Even When Using A Seatbelt In These Scenarios.

Translational and Rotational Head Kinematics in Side Impact

2009 ◽  
Author(s):  
Jiangyue Zhang ◽  
Narayan Yoganandan ◽  
Frank A. Pintar
Keyword(s):  
Brain Injuries ◽  
Motor Vehicle ◽  
Skull Fracture ◽  
Diffuse Axonal Injury ◽  
Side Impact ◽  
Head Acceleration ◽  
Head Kinematics ◽  
Head Injury Criterion ◽  
Side Impacts ◽  
Standard Sets

Regulatory tests use translational head accelerations and its derived variable HIC (head injury criterion) as the criteria for automotive vehicle crashworthiness evaluation. The FMVSS standard sets HIC36 of 1000 as the threshold for frontal impact protection. On the other hand, rotational head kinematics, such as rotational accelerations and velocities, has been attributed to brain injury in the motor vehicle environment for more than six decades [1–5]. As documented in recent real-world case studies, severe brain injuries without skull fracture, such as diffuse axonal injury, can result from rotational head motions in side impacts even at low change in impact velocity [6, 7]. Because the HIC only accounts for the translational head accelerations, there is no clear evidence showing there is a direct correlation between translational and rotational head acceleration. Therefore, it is important to quantify the correlation between head translational and rotational accelerations and HIC, in side impacts. Consequently, the current research was designed with this purpose.

scholarly journals Distress disclosure and psychological Distress among men: the role of feeling understood and loneliness

2021 ◽  
Author(s):  
Brian TaeHyuk Keum ◽  
John L. Oliffe ◽  
Simon M. Rice ◽  
David Kealy ◽  
Zac E. Seidler ◽  
...  
Keyword(s):  
Psychological Distress ◽  
Group Analysis ◽  
Mediation Model ◽  
Adult Men ◽  
Path Analyses ◽  
Asian Men ◽  
Race Ethnicity ◽  
Post Hoc ◽  
Distress Disclosure ◽  
Better Than

AbstractWe examined whether men’s distress disclosure would be indirectly associated with psychological distress through feeling understood by others and loneliness as serial or parallel mediators. We conducted path analyses (N = 1827 adult men; mean 37.53 years, SD = 14.14) to test the mediators while controlling for race/ethnicity. Post-hoc multi-group analysis was conducted to examine differences across White and Asian men. The serial mediation model fit the data better than the parallel mediation model. Controlling for race/ethnicity, a significant partial indirect association was found between greater distress disclosure and lower psychological distress through greater feelings of being understood and lower feelings of loneliness. Post-hoc multi-group analysis suggested that the hypothesized paths fit equivalently across White and Asian men, and the direct effect was not significant for Asian men. Our hypothesized serial model also fit the data significantly better than alternative models with distress and the mediators predicting disclosure. Distress disclosure may be a socially conducive strategy for men to feel understood and socially connected, a process that may be associated with lower psychological distress.

scholarly journals Comparison of branded rugby headguards on their effectiveness in reducing impact on the head

2018 ◽  
Vol 4 (1) ◽  
pp. e000361 ◽  
Author(s):  
Erin R A Frizzell ◽  
Graham P Arnold ◽  
Weijie Wang ◽  
Rami J Abboud ◽  
Tim S Drew
Keyword(s):  
Impact Force ◽  
Linear Acceleration ◽  
Baseline Measurement ◽  
Peak Acceleration ◽  
Impact Forces ◽  
Impact Attenuation ◽  
The Mean ◽  
Force Reduction ◽  
The Right ◽  
The Impact

AimTo compare the available brands of rugby headguards and evaluate their impact attenuation properties at various locations on the cranium, with regard to concussion prevention.MethodsSeven different branded headguards were fitted onto a rigid headform and drop-tested in three different positions. An accelerometer measured the linear acceleration the headform experienced on impact with the ground. Each test involved dropping the headform from a height that generated 103.8 g on average when bare, which is the closest acceleration to the upper limit of the concussion threshold of 100 g. A mean peak acceleration for each drop position was calculated and compared with the bare baseline measurement.ResultsEach headguard demonstrated a significant decrease in the mean peak acceleration from the baseline value (all p≤0.01). Overall the Canterbury Ventilator was the most effective headguard, decreasing the impact force on average by 47%. The least effective was the XBlades Elite headguard, averaging a force reduction of 27%. In five of the seven headguards, the right side of the headwear was the most effective at reducing impact force.ConclusionOverall, the results indicate that it would be beneficial to wear a headguard during rugby in order to reduce the impact forces involved in head collisions. There was also a clear difference in performance between the tested brands, establishing the Canterbury headguard as the most effective. However, only one model of headguard from each brand was tested, so further research evaluating all other models should be considered.

scholarly journals Which Test of Divergent Thinking Is Best?

2016 ◽  
Vol 3 (1) ◽  
pp. 4-18 ◽  
Author(s):  
Mark A. Runco ◽  
Ahmed M. Abdulla ◽  
Sue Hyeon Paek ◽  
Fatima A. Al-Jasim ◽  
Hanadi N. Alsuwaidi
Keyword(s):  
Divergent Thinking ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Mixed Model Analysis ◽  
Demographic Questionnaire ◽  
Problem Generation ◽  
Behavior Scale ◽  
Realistic Problem ◽  
Post Hoc ◽  
Better Than

AbstractDivergent thinking (DT) tests are probably the most commonly used measures of creative potential. Several extensive batteries are available but most research relies on one or two specific tests rather than a complete battery. This may limit generalizations because tests of DT are not equivalent. They are not always highly inter-correlated. Additionally, some DT tests appear to be better than others at eliciting originality. This is critical because originality is vital for creativity. The primary purpose of the present study was to determine which test of DT elicits the most originality. Seven measures of DTwere administered on a sample of 611 participants in eight Arabic countries. The tests were Figural, Titles, Realistic Presented Problems, Realistic Problem Generation, Instances, Uses, and Similarities. The Quick Test of Convergent Thinking, Runco’s Ideational Behavior Scale, and a demographic questionnaire were also administered. A linear mixed model analysis confirmed that the originality scores in the DT tests differed by test. Post-hoc tests indicated that the Titles and Realistic Problem Generation tests produced the highest mean originality scores, whereas the Realistic Presented Problems test produced the lowest mean originality scores. These differences confirm that research using only one DT test will not provide generalizable results.

The range of bicycle helmet performance at real world impact locations

2021 ◽  
pp. 175433712110577
Author(s):  
Ann R Harlos ◽  
Steven Rowson
Keyword(s):  
Real World ◽  
Test Line ◽  
Linear Acceleration ◽  
The United States ◽  
Consumer Product Safety Commission ◽  
Bicycle Helmets ◽  
Impact Location ◽  
Increased Risk ◽  
Post Hoc ◽  
The Impact

In the United States, all bicycle helmets must comply with the standard created by the Consumer Product Safety Commission (CPSC). In this standard, bike helmets are only required to by tested above an established test line. Unregulated helmet performance below the test line could pose an increased risk of head injury to riders. This study quantified the impact locations of damaged bike helmets from real-world accidents and tested the most commonly impacted locations under CPSC bike helmet testing protocol. Ninety-five real-world impact locations were quantified. The most common impact locations were side-middle (31.6%), rear boss-rim (13.7%), front boss-rim (9.5%), front boss-middle (9.5%), and rear boss-middle (9.5%). The side-middle, rear boss-rim, and front boss (front boss-middle and front boss-rim regions combined) were used for testing. Two of the most commonly impacted regions were below the test line (front boss-rim and rear boss-rim). Twelve purchased helmet models were tested under CPSC protocol at each location for a total of 36 impacts. An ANOVA test showed that impact location had a strong influence on the variance of peak linear acceleration (PLA) ( p = 0.002). A Tukey HSD post hoc test determined that PLA at the side-middle (214.9 ± 20.8 g) and front boss (228.0 ± 39.6 g) locations were significantly higher than the PLA at the rear boss-rim (191.5 ± 24.2 g) location. The highest recorded PLA (318.8 g) was at the front boss-rim region. This was the only test that exceeded the 300 g threshold. This study presented a method for quantifying real-world impact locations of damaged bike helmets. Higher variance in helmet performance was found at the regions on or below the test line than at the region above the test line.

scholarly journals Thermal Comfort Evaluation of Rooms Installed with STPV Windows

Energies ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 808 ◽  
Author(s):  
Hao Tian ◽  
Wei Zhang ◽  
Lingzhi Xie ◽  
Zhichun Ni ◽  
Qingzhu Wei ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Indoor Environment ◽  
Thermal Sensation ◽  
Test Results ◽  
Test Unit ◽  
Maximum Difference ◽  
Test Rig ◽  
Comfort Evaluation ◽  
The Difference ◽  
Better Than

Thermal comfort is an important aspect to take into consideration for the indoor environment of a building integrated with a semi-transparent Photovoltaics (STPV) system. The thermal comfort of units with photovoltaic windows and that of conventional windows, which is an ordinary without PV, were evaluated via on-site tests and questionnaires. Using the thermal comfort investigation of the test rig, the maximum difference in air temperature was found to be around 5 °C between test unit and comparison unit. The predicted mean vote (PMV)–predicted percentage dissatisfied (PPD) value of the test unit was better than that of the comparison unit. It was observed that on sunny days, the PMV value ranged from 0.2 (nature) to 1.3 (slightly warm) in the test unit, and that of the comparison unit was 0.7 (slightly warm) to 2.0 (warm), thereby providing better thermal comfort, especially during mornings. The maximum difference in PPD values was found to reach 27% between the two units at noon. On cloudy days, the difference was negligible, and the thermal sensation between the foot and the head were almost the same. Fifty respondents were asked to complete a carefully designed questionnaire. The thermal sensation of the test unit was better than that of comparison unit, which corresponded with the test results. Thermal, lighting, acoustic, and other environment comfort scores were combined, and the acceptance of the test unit with the STPV windows was found to be 73.8%. The thermal sensation difference between men and women was around 5%. Thus, during summer, STPV windows can improve the thermal comfort and potentially reduce the air-conditioning load.

scholarly journals Warning ‘Don't spread’ versus ‘Don't be a spreader’ to prevent the COVID-19 pandemic

2020 ◽  
Vol 7 (9) ◽  
pp. 200793
Author(s):  
Fumiya Yonemitsu ◽  
Ayumi Ikeda ◽  
Naoto Yoshimura ◽  
Kaito Takashima ◽  
Yuki Mori ◽  
...  
Keyword(s):  
Social Cognition ◽  
Data Collection ◽  
Effect Size ◽  
Infection Prevention ◽  
Ministry Of Health ◽  
Self Identity ◽  
Data Collection And Analysis ◽  
Stage 1 ◽  
Post Hoc ◽  
Better Than

The coronavirus disease 2019 (COVID-19) outbreak is threatening not only health but also life worldwide. It is important to encourage citizens to voluntarily practise infection-prevention (IP) behaviours such as social distancing and self-restraint. Previous research on social cognition suggested that emphasizing self-identity is key to changing a person's behaviour. The present study investigated whether reminders that highlight self-identity would be effective in changing intention and behaviour related to the COVID-19 outbreak, and hypothesized that those who read reminders highlighting self-identity (Don't be a spreader) would change IP intention and behaviour better than those who read ‘Don't spread’ or no reminder. We conducted a two-wave survey of the same participants with a one-week interval, during which we assigned one of three reminder conditions to the participants: ‘Don't spread’ (spreading condition), ‘Don't be a spreader’ (spreader condition) and no reminder (control condition). Participants marked their responses to IP intentions and actual behaviours each week based on the Japanese Ministry of Health, Labour and Welfare guidelines. While the results did not show significant differences between the conditions, the post hoc analyses showed significant equivalence in either IP intentions or behavioural scores. We discussed the results from the perspective of the effect size, ceiling effects and ways of manipulation checks as future methods with more effective persuasive messaging. Following in-principle acceptance, the approved Stage 1 version of this manuscript was pre-registered on the OSF at https://doi.org/10.17605/OSF.IO/KZ5Y4. This pre-registration was performed prior to data collection and analysis.

scholarly journals Biomechanical head impact characteristics during sparring practice sessions in high school taekwondo athletes

2017 ◽  
Vol 19 (6) ◽  
pp. 662-667 ◽  
Author(s):  
David M. O'Sullivan ◽  
Gabriel P. Fife
Keyword(s):  
High School ◽  
Rotational Velocity ◽  
Linear Acceleration ◽  
Head Impact ◽  
Rotational Acceleration ◽  
Head Impacts ◽  
Head Injury Criterion ◽  
Impact Location ◽  
Male High School ◽  
Impact Characteristics

OBJECTIVEThe purpose of this study was to monitor head impact magnitude and characteristics, such as impact location and frequency, at high school taekwondo sparring sessions.METHODSEight male high school taekwondo athletes participated in this study. The head impact characteristics were recorded by X-Patch, a wireless accelerometer and gyroscope, during 6 taekwondo sparring sessions. The outcome measures were the peak linear acceleration (g = 9.81 msec2), peak rotational acceleration, rotational velocity, and Head Injury Criterion.RESULTSA total of 689 impacts occurred over 6 sessions involving the 8 athletes. There was an average of 24 impacts per 100 minutes, and there were significant differences in the frequency of impacts among both the sessions and individual athletes. In order of frequency, the most commonly hit locations were the side (38.2%), back (35.7%), and front (23.8%) of the head.CONCLUSIONSThe data indicate that there is a relatively high number of head impacts experienced by taekwondo athletes during sparring practice. According to the rotational acceleration predicting impact severity published in previous research, 17.1% of the impacts were deemed to be a moderate and 15.5% were deemed to be severe.

Kinderliteratuur als Knooppunt

1998 ◽  
Vol 59 ◽  
pp. 57-65
Author(s):  
Marianne Hermans
Keyword(s):  
Reading Skills ◽  
Peer Group ◽  
Basic Research ◽  
Schema Theory ◽  
Word Knowledge ◽  
Stepping Stones ◽  
Domain Specific ◽  
New Information ◽  
Post Hoc ◽  
Better Than

The results of the pilot study reported on in this article indicate that the combination of children's books supplementary to the biology lessons does not diminish reading-achieve-ment test scores, and that there seems to be an advantage in domain-specific word knowledge. For 14 weeks, the time normally spent on unsustained silent reading in class was filled in by reading on particular subjects that were being discussed in biology lessons. The basic research assumption was that reading various texts on the same subject would not only positively affect the children's knowledge about this subject but would also improve their reading skills and their attitudes towards reading. The experimental group scored significandy better than their peer group on a domain-specific vocabulary test. This indicates that the books were used as stepping stones for building mental knowledge structures. Tests with respect to the other variables such as reading skills yielded no significant differences between the groups. However, post-hoc analysis showed an advantage for pupils from the lower social groups. Their attitude towards reading impro-ved considerably, in which respect they differed significandy from their peers. The results seem to confirm the ideas expressed in the international literature about content area reading and in aspects of schema theory. By reading the books in combination with the biology lessons, certain schemata could be activated which enable the pupils better to understand the new information and store it firmly in their memory. The redundancy of important words appearing in various contexts is a determinant of word knowledge.

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