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Rhabdomyosarcoma (RMS) is a pediatric malignancy of the muscle with characteristics of cells blocked in differentiation. NOTCH1 is an oncogene that promotes self-renewal and blocks differentiation in the fusion negative-RMS sub-type. However, how NOTCH1 expression is transcriptionally maintained in tumors is unknown. Analyses of SNAI2 and CTCF chromatin binding and HiC analyses revealed a conserved SNAI2/CTCF overlapping peak downstream of the NOTCH1 locus marking a sub-topologically associating domain (TAD) boundary. Deletion of the SNAI2-CTCF peak showed that it is essential for NOTCH1 expression and viability of FN-RMS cells. Reintroducing constitutively activated NOTCH1-ΔE in cells with the SNAI2-CTCF peak deleted restored cell-viability. Ablation of SNAI2 using CRISPR/Cas9 reagents resulted in the loss of majority of RD and SMS-CTR FN-RMS cells. However, the few surviving clones that repopulate cultures have recovered NOTCH1. Cells that re-establish NOTCH1 expression after SNAI2 ablation are unable to differentiate robustly as SNAI2 shRNA knockdown cells; yet, SNAI2-ablated cells continued to be exquisitely sensitive to ionizing radiation. Thus, we have uncovered a novel mechanism by which SNAI2 and CTCF maintenance of a sub-TAD boundary promotes rather than represses NOTCH1 expression. Further, we demonstrate that SNAI2 suppression of apoptosis post-radiation is independent of SNAI2/NOTCH1 effects on self-renewal and differentiation. [ABSTRACT FROM AUTHOR]

Pedestrians suffer significant injuries from ground contact, but attempts to reduce them have been limited. A recent study using multi-body simulations showed ground contact injury may be improved by controlling vehicle braking. The aim of the study is to assesses whether controlled braking would be beneficial in real-world collisions. PC-Crash was used to reconstruct 150 freely available real-world vehicle pedestrian video collisions. Pairwise comparison of actual versus controlled braking was then performed for each case. Pedestrian injury evaluation metrics included head injury criterion HIC15 and pelvis contact force, and another metric named separation distance between the vehicle and pedestrian at the instant of ground contact was used to test the feasibility of external airbags for mitigating ground contact. Substantial head and pelvis injury reductions may be possible through the application of controlled braking. Full vehicle braking after first vehicle-pedestrian contact has little influence on overall pedestrian injury outcome. In controlled braking, an external semi-elliptic airbag with a range 2 m can prevent 83.1% ground contact (only 46.6% in actual cases) and there is a high probability (50%) that the available space to control braking is limited if the vehicle deviates from its original lane. Various kinematic explanations are presented, consistent with the principle that the vertical component of the impact on the ground can be reduced by controlling the vehicle braking. Despite the variation in real-world pedestrian collisions, controlled braking may generally provide a benefit for ground contact injuries. [ABSTRACT FROM AUTHOR]

In order to focus on the injury mechanism of electric cyclists in the collision accident between right turn of truck and electric bicycle, Pc-Crash is used to value the injury of the electric cyclist in this paper. Through repeated tests in Pc-Crash, it was found that two dynamic response process were existed. The electric bicycle and cyclist collided with truck, and the electric bicycle and cyclist were thrown to the ground due to the impact force. Finally, they were crushed under certain conditions. The multi-rigid-body truck model is built on the theories of multi-rigid-body modeling and multi-rigid-body collision to get the value of the crushed part which the single rigid model can't calculate. After that, we analyze HIC, continuous 3 ms resultant acceleration of chest, the shear force of femur and leg, based on the electric bicycle speed, the mass of electric bicycle and cyclist, the height of cyclist's seat. We found that when the electric cyclist is not crushed by the truck, the value of each damage index is below the threshold. But when the cyclist is crushed by the truck, the damage index of the part where the cyclist is crushed exceeds the threshold, and causes fatal injury to the cyclist. So, reducing the possibility of crushing can improve the safety level of electric cyclists. [ABSTRACT FROM AUTHOR]

This research analyzes the head and chest injuries with a finite element model of Hybrid III six years old during the vehicle rollover, using a passive safety Child restraint system (CRS). Vehicle seats and passive safety systems were modeled in CAD software. Subsequently, all elements were analyzed using the finite element method in the LS-DYNA® software. The border conditions were established for each study, in accordance with the Federal Motor Vehicle Safety Standard (FMVSS), following the FMVSS 213 standard for the mounting and fastening of the infant, the FMVSS 208 for the dolly rollover test methodology with which the vehicle rollover was performed. The vehicle Toyota Yaris 2010 was considered in all the analyzes. The numerical simulations were performed during an interval of 1 s, and there were obtained values every 2 ms to analyze the efficiency of the system and the restriction performance of the CRS system. It was compared the behavior when the chair uses a 5-point seatbelt, with respect to using the 3-point seatbelt, and what happens when holding the chair with the single seatbelt and with the ISOFIX anchorage. Three cases of studies were analyzed: Study I; CRS Study II; CRS with ISOFIX anchorage; and Study III; CRS with a seatbelt of 5-points. The outcome shows that the best restriction efficiency is that of the CRS 5 points seatbelt because it presents the lowest level of chest injury. In conclusion, the main factor to reduce injuries during a rollover accident is the correct anchoring of CRS, this is achieved with ISOFIX system, on the other hand, a good quality of material and a correct thickness used for the headrest could reduce the risk of a head injury. [ABSTRACT FROM AUTHOR]

Objective: The objective was to quantify head injury metric sensitivity of the 50th percentile male Hybrid III, THOR, and Global Human Body Models Consortium simplified occupant (GHBMC M50-OS) to changes in loading conditions in loading regimes that may be experienced by occupants of spaceflight vehicles or highly autonomous vehicles (HAVs) with nontraditional seating configurations. Methods: A Latin hypercube (LHD) design of experiments (DOE) was employed to develop boundary conditions for 455 unique acceleration profiles. Three previously validated finite element (FE) models of the Hybrid III anthropomorphic test device (ATD), THOR ATD, and GHBMC M50-OS were positioned in an upright 90°-90°-90° seat and with a 5-point belt. Acceleration pulses were applied to each of the three occupants in the ± X, +Y, and ± Z directions, with peak resultant acceleration magnitudes ranging from 5 to 20 G and times to peak ranging from 32.5 to 120.8 ms with duration 250 ms, resulting in 1,248 simulations. Head injury metrics included peak linear head acceleration, peak rotational head acceleration, head injury criteria (HIC15), and brain injury criteria (BrIC). Injury metrics were regressed against boundary condition parameters using 2nd order multiple polynomial regression, and compared between occupants using matched pairs Wilcoxon signed rank analysis. Results: Across the 416 matched-simulations that reached normal termination with all three models, HIC15 values ranged from 1.0–396.5 (Hybrid III), 1.2–327.9 (THOR), and 0.6–585.6 (GHBMC). BrIC ranged from 0.03–0.95 (Hybrid III), 0.03–1.21 (THOR), and 0.04–0.84 (GHBMC). Wilcoxon signed rank analysis demonstrated significant pairwise differences between each of the three occupant models for head injury metrics. For HIC15, the largest divergence between GHBMC and the ATDs was observed in simulations with components of combined underbody and rear impact loading. The three models performed most similarly with respect to BrIC output when loaded in a frontal direction. Both the GHBMC and the Hybrid III produced lower values of BrIC than the THOR on average, with the differences most pronounced in rear impact loading. Conclusion: In conclusion, observed differences between the occupant models' head injury metric output were quantified. Loading direction had a large effect on metric outcome and metric comparability across models, with frontal and rear impacts with low vertical acceleration tending to be the most similar. One explanation for these differences could be the differences in neck stiffness between the models that allowed more rotation in the GHBMC and THOR. Care should be taken when using ATDs as human volunteer surrogates in these low energy events. [ABSTRACT FROM AUTHOR]

An investigation was conducted in terms of the variation of particle size distribution, removing hydrophilic groups from coal surface, reagent dispersion, and formation of particles-bubbles aggregates resulted from the HIC to elucidate the mechanisms responsible for improvement in flotation performance. Results showed that the amount of <0.074 mm size fraction increased after HIC. It would have a negative effect on flotation performance, although the variation was not significant. Reagant dispersion had a marginal effect on flotation performance. The contact angle measurements indicated that HIC improved particle surface hydrophobicity, and the effect was most significant when agitation speed of the HIC was 2000 rpm, but the flotation performance was not as significant as expected. When HIC agitation speed was 1500 rpm, particles-bubbles aggregates were formed; however, the aggregates were destroyed as agitation speed increased to 2000 rpm. This fact was consistent with the experimental results that the flotation performance was optimal with the HIC speed of 1500 rpm and it deteriorated as agitation speed increased to 2000 rpm. It was deduced that the size and structure stability of particles-bubbles aggregates played a dominant role in the improvement in flotation performance. [ABSTRACT FROM AUTHOR]

MPS (Motorcyclists´ protection systems) play an essential role in the reduction of fatalities and morbidity involved in motorbike and moped accidents, since they offer protection from impact against road elements such as guardrail posts and nearby elements such as traffic signs, trees, etc. For the standardisation of such elements, different regulations have been developed which, by means of experimental tests, allow the simulation of those accidents through tests at a specific velocity and angle. Nevertheless, there is the possibility that, under different angles and velocity, those systems fail to be safe. To assess this, a series of accidents involving diverse angles and velocities have been studied through virtual tests by using numerical models and the finite elements method with a view to obtaining data on head acceleration and neural damage sustained in the event of collision against MPS. In addition, the accidentology for this type of vehicles has been studied in order to break accidents down according to impact angle and velocity impact range as well as age category and gender of those sustaining injuries. To that aim, homologated commercial MPS have been analysed in order to get the variation of the main biomechanical indexes depending on the impact angle and velocity; the results thus obtained have allowed us to determine the real security level of the MPS studied. This information has been extrapolated to determine the level of security provided by MPS. Finally some modifications in the homologation regulations to improve safety of MPS have been suggested. [ABSTRACT FROM AUTHOR]

There is a rare group of HIV-1-infected individuals who show permanent control of clinical progression for over 10 years, maintain CD4+ cells >500 μl and have undetectable viral loads; they are designated long-term non-progressors elite controllers (LTNPs ECs). Multiple studies have demonstrated the necessary contribution of at least two of host, immune and viral factors to the LTNP phenotype. This group of individuals is not homogenous because of the different involvement of these factors. We will review the role of each of these and their combinations to the LTNP EC phenotype. LTNP EC individuals offer an opportunity for the investigation into the mechanisms for the spontaneous control of HIV infection. [ABSTRACT FROM AUTHOR]

This study concerns the development of an experimental method intended to estimate the effectiveness of restraint systems for forklift truck drivers during a lateral tip-over. Tests performed on human subjects placed in situations of partial lateral tip-over were used to modify a HYBRID III dummy and to validate its performance. Another more realistic test setup was used to simulate a 90° lateral tip-over and assess the effectiveness of market restraint systems. The results show that systems that kept the dummy inside the cab (door-bar systems, seat-belt, etc.) would considerably increase the driver's chances of survival. Conversely, other poorly dimensioned equipment might not block the dummy's movement or might break. Head injury criteria (HIC15) calculation gave values lower than the threshold of 560 that was set in our approach for impacts inside the cab, whereas our assessments showed that impacts with the ground could be very serious or fatal. [ABSTRACT FROM AUTHOR]

The image of the Israeli soldier has transmuted over time. This is particularly true when examining this image in Israeli media. As media reflects social changes, understanding the development of the image of the Israeli soldier in Israeli media may be indicative of wider transformations. During the 1982 Lebanon War the Israeli soldier was identified chiefly as a tough, masculine figure; a warrior. In the 1990s, there was a gradual transformation into a more vulnerable image: a scared, fragile survivor, who wants to return home in one piece. Conversely, during the first decade of the twenty-first century, the framing of the Israeli soldier becomes more complex, with both images present in the media. However, despite the fact both images appear, during this final period the ‘warrior’ image receives more visibility. Using theoretical literature from the fields of communications and civil–military–media relations, and covering two major Israeli news publications –Yediot AharonotandHaaretz– this article traces the image of the Israeli soldier from the 1982 Lebanon War (1982) to Operation Cast Lead (2008–9). [ABSTRACT FROM AUTHOR]

Pedestrian headform impact tests are generally carried out at a fixed impact speed, which varies depending on the test protocol in use. Thus, it may be desirable to extrapolate a single test result to higher and lower test speeds. This paper investigates the influence of impact speed on the Head Injury Criterion (HIC) and the peak dynamic displacement. The relationship between impact speed and these test measurements is first considered analytically using a linear spring model, and then empirically using the results of 29 headform tests on seven different locations. The results indicate that power functions can be used to predict the effect of impact speed, with exponents of approximately 2.5 for HIC and 0.8 for peak displacement. These relationships might be used for assessing head impact performance over a wider range of speeds than are presently tested. [ABSTRACT FROM PUBLISHER]

Objective: To compare the predictions of the head injury criterion (HIC), currently used to predict the risk of traumatic brain injury in frontal vehicle impact and pedestrian impact tests, with the predictions of other empirical and analytical injury metrics. Methods: The appropriateness of different criteria relative to injury metrics derived from a head finite element (FE) model is investigated for different deceleration pulses in this research. Empirical injury metrics are computed by direct calculation for different analyzed pulses. In addition, for each pulse full FE model simulations of a complete human head were performed by means of the SIMon model. The computations are used to calculate the analytical injury metrics. Results: This article shows that an optimal head deceleration curve based on HIC does not minimize other analytical injury metrics. The results obtained in this study suggest that the HIC criterion does not necessarily provide the same severity ranking for different external loadings to the head as the injury metrics derived from the FE models. Conclusion: Countermeasures designed based only on HIC could differ significantly from those based on analytical injury measures computed by FE models. The use of multiple injury metrics is recommended given that no scalar measure seems to be positively and strongly correlated with relevant injury metrics. [ABSTRACT FROM AUTHOR]

This paper evaluates the consequences of the impact of an unrestrained object against the head of vehicle occupant during a frontal crash by means of a computational head-neck biomechanical model. The correct positioning of head restraints can partially protect the rear side of the head, but there is still a significant probability of being injured. However, because head restraints are typically not properly adjusted as whiplash studies have shown, the probability of being impacted by an unrestrained object during a frontal crash is noticeably high and hence the risk of being injured is also high. In this work, head injury risk is evaluated through the Head Injury Criterion (HIC), by simulating a complete head-neck biomechanical model with realistic motion under frontal crash condition. The model developed includes all cervical vertebrae, intervertebral discs, ligaments and muscles. The model was validated against experimental data. Results have shown that the risk of severe head injury in frontal collision due to unrestrained objects cannot be neglected. The risk is directly related to the mass of the impact object, the relative velocity between the object and the head and the incorrect use of the head restraint. [ABSTRACT FROM AUTHOR]

Roadside barriers are homologated in Europe to EN1317, which includes tests for containment (resistance to penetration by an impacting vehicle), and accident severity, measured by acceleration severity index (ASI) and theoretical head impact velocity (THIV). Barriers are classed according to ASI measurement. There has been debate as to whether class C barriers (ASI 1.5 to 1.9) should be considered acceptable from an injury risk point of view, but the debate has been hampered by lack of quantitative correlation between accident severity level and injury risk. This study presents data from three physical crash tests and 50 computer simulations. A small car equipped with crash dummy was impacted into a barrier at a range of speeds and angles, and with variations to the vehicle conditions and occupant positions. Measurements from the crash dummy in the tests and simulations were compared with published injury limits derived from volunteer and cadaver tests and plotted against ASI and THIV. Results showed that, although ASI did show a correlation with injury risk, the level chosen for the boundary between class B and C barriers in EN1317 does not provide significant discrimination between higher and lower risk of injury. However, the EN1317 limit for THIV, which applies to all barrier classes, was found to be a reliable discriminator between acceptable and unacceptable injury risk. [ABSTRACT FROM AUTHOR]

This paper presents an approach to analyze drivers' behaviours during critical events using a driving simulator and to estimate the dynamic responses of drivers by means of numerical simulation. The first part of this work is to present the experimental results obtained from 35 subject responses. A scenario of an unavoidable crash is created in the simulator-based experiment. All drivers swerved away in order to avoid the truck heading straight towards them. It was observed that 30% of the subjects placed their left hand at the right side of the steering wheel. In the second part, five classes of driver pre-crash behaviours are defined and then analyzed with Madymo®. The load applied to the virtual dummy corresponded to the deceleration undergone by a car during a head-on collision at 50 km/h. The results of the simulation emphasized a critical situation which could lead to a mortal traumatism. [ABSTRACT FROM AUTHOR]