Integrating Human and Nonhuman Primate Data to Estimate Human Tolerances for Traumatic Brain Injury.

Traumatic brain injury (TBI) contributes to a significant portion of the injuries resulting from motor vehicle crashes, falls, and sports collisions. The development of advanced countermeasures to mitigate these injuries requires a complete understanding of the tolerance of the human brain to injury. In this study, we developed a new method to establish human injury tolerance levels using an integrated database of reconstructed football impacts, subinjurious human volunteer data, and nonhuman primate data. The human tolerance levels were analyzed using tissue-level metrics determined using harmonized species-specific finite element (FE) brain models. Kinematics-based metrics involving complete characterization of angular motion (e.g., diffuse axonal multi-axial general evaluation (DAMAGE)) showed better power of predicting tissue-level deformation in a variety of impact conditions and were subsequently used to characterize injury tolerance. The proposed human brain tolerances for mild and severe TBI were estimated and presented in the form of injury risk curves based on selected tissue-level and kinematics-based injury metrics. The application of the estimated injury tolerances was finally demonstrated using real-world automotive crash data.

Glycolipid nanotube templates for the production of hydrophilic/hydrophobic and left/right-handed helical polydiacetylene nanotubes.

Encapsulation and preorganization of diacetylene monomers in glycolipid nanotubes allows for the production of polydiacetylene nanotubes with hydrophilic/hydrophobic surfaces and left/right-handed helicities.

Influences of Hydrogen Bonding-Based Stabilization of Bolaamphiphile Layers on Molecular Diffusion within Organic Nanotubes Having Inner Carboxyl Groups.

This paper reports molecular diffusion behavior in two bolaamphiphile-based organic nanotubes having inner carboxyl groups with different inner dimeters (10 and 20 nm) and wall structures, COOH-ONT10nm and COOH-ONT20nm, using imaging fluorescence correlation spectroscopy (imaging FCS). The results were compared to those previously obtained in a similar nanotube with inner amine groups (NH2-ONT10nm). COOH-ONT10nm, as with NH2-ONT10nm, were formed from a rolled bolaamphiphile layer incorporating triglycine moieties, whereas COOH-ONT20nm consisted of four stacks of triglycine-free bolaamphiphile layers. Imaging FCS measurements were carried out for anionic sulforhodamine B (SRB), zwitterionic/cationic rhodamine B (RB), and cationic rhodamine-123 (R123) diffusing within ONTs (1-9 µm long) at different pH (3.4-8.4) and ionic strengths (1.6-500 mM). Diffusion coefficients (D) of these dyes in the ONTs were very small (0.01-0.1 µm2/s), reflecting the significant contributions of molecule-nanotube interactions to diffusion. The D of SRB was larger at higher pH and ionic strength, indicating the essential role of electrostatic repulsion that was enhanced by the deprotonation of the inner carboxyl groups. Importantly, the D of SRB was virtually independent of nanotube inner diameter and wall structure, indicating the diffusion of the hydrophilic molecule was controlled by short time scale adsorption/desorption processes onto the inner surface. In contrast, pH effects on D were less clear for relatively hydrophobic R123 and RB, suggesting the significant contributions of non-Coulombic interactions. Interestingly, the diffusion of these molecules in COOH-ONT20nm was slower than in COOH-ONT10nm. Slower diffusion in COOH-ONT20nm was attributable to relatively efficient partitioning of the hydrophobic dyes into the bolaamphiphile layers, which was reduced in COOH-ONT10nm due to the stabilization of its layer by polyglycine-II-type hydrogen bonding networks. These results show that, by tuning the bolaamphiphile structures and their intermolecular interactions, unique environments can be created within the nanospaces for enhanced molecular separations and reactions.

Relationship between frontal car-to-car test result and vehicle crash compatibility evaluation in mobile progressive deformable barrier test.

Objective: In 2020, the world's first crash compatibility rating test will be introduced in the European mobile progressive deformable barrier (MPDB) test. In this research, the quantitative change in partner protection performance of large vehicles in car-to-car (C2C) impacts was studied if these large vehicles were designed in future based on MPDB tests addressing crash compatibility ratings. Methods: Representative vehicles of the European fleet were selected and a Computer Aided Engineering (CAE) parameter study was conducted. In particular, by changing an indicator of structural interaction performance (SD; i.e., the degree of uniformity of barrier deformation)/mass/stiffness of large vehicles systematically in a step-by-step approach, the compatibility evaluation results of large vehicles in MPDB and the occupant injury score of small vehicles in C2C impacts were compared. The CAE result was evaluated compared to that of C2C physical impact tests. Results: The CAE parameter study showed that in the C2C impact condition, the effects on occupant injury in a small vehicle due to changes in the large vehicle were as follows: (1) SD change: The effect was minor except for small overlap condition. (2) Mass and stiffness change: The effect was relatively major. On the other hand, compatibility evaluation in the MPDB showed a tendency to overestimate the effect of SD change in comparison with the above-mentioned C2C impact condition. In addition, physical impact tests showed that, based on SD evaluation, the large vehicle with a relatively inferior compatibility rating compared to those with superior compatibility ratings showed a contradicting trend of better compatibility performance in the C2C test. Conclusions: The currently proposed compatibility evaluation method of the MPDB test showed some tendency to overestimate the effect of SD change and resulted in quantitatively inconsistent outcomes regarding occupant injury in the partner car in C2C impact conditions.

Diffusion Behavior of Differently Charged Molecules in Self-Assembled Organic Nanotubes Studied Using Imaging Fluorescence Correlation Spectroscopy.

The diffusion behavior of fluorescent molecules within bolaamphiphile-based organic nanotubes (ONTs) was systematically investigated using imaging fluorescence correlation spectroscopy (imaging FCS). Anionic sulforhodamine B, zwitterionic/cationic rhodamine B, or cationic rhodamine 123 was loaded into ONTs having cylindrical hollow structures (ca. 10 nm in inner diameter) with amine and glucose groups on the inner and outer surfaces, respectively. Wide-field fluorescence video microscopy was used to acquire imaging FCS data for dye-doped ONTs in aqueous solutions of different ionic strengths (1-500 mM) at different pH (3.4-8.4). The diffusion behavior of these dyes was discussed on the basis of their apparent diffusion coefficients ( D) that were determined by autocorrelating the time transient of fluorescence intensity at each pixel on an ONT. Molecular diffusion in the ONTs was significantly slowed by the molecule-nanotube interactions, as shown by the very small D (10-1 to 10-2 µm2/s). The pH dependence of D revealed that dye diffusion was basically controlled by electrostatic interactions associated with the protonation of the amine groups on the ONT inner surface. The pH-dependent change in D was observed over a wide pH range, possibly because of electrostatically induced variations in the p Ka of the densely packed ammonium ions on the ONT inner surface. On the other hand, the influence of ionic strength on D was relatively unclear, suggesting the involvement of non-Coulombic interactions with the ONTs in molecular diffusion. Importantly, individual ONTs of different lengths (1-5 µm) afforded similar diffusion coefficients for each type of dye at each solution condition, implying that the properties of the ONTs were uniform in terms of solute loading and release. These results highlight the characteristics of the molecular diffusion behavior within the ONTs and will help in the design of ONTs better suited for use as drug vehicles and contaminant adsorbents.

Reference PMHS Sled Tests to Assess Submarining of the Small Female.

In the last decade, extensive efforts have been made to understand the physics of submarining and its consequences in terms of abdominal injuries. For that purpose, 27 Post Mortem Human Subject (PMHS) tests were performed in well controlled conditions on a sled and response corridors were provided to assess the biofidelity of dummies or human body models. All these efforts were based on the 50th percentile male. In parallel, efforts were initiated to transfer the understanding of submarining and the prediction criteria to the THOR dummies. Both the biofidelity targets and the criteria were scaled down from the 50th percentile male to the 5th percentile THOR female. The objective of this project was to run a set of reference PMHS tests in order to check the biofidelity of the THOR F05 in terms of submarining. Three series of tests were performed on nine PMHS, the first one was designed to avoid submarining, the second and third ones were designed to result in submarining. In the first configuration, no submarining was observed in 3 cases out of 4 and only one iliac wing fracture occurred in one subject. In the second and third configurations, all subjects but one sustained submarining. In addition, two subjects out of three in the third configuration sustained substantial iliac wing fractures. Nevertheless, all configurations can be represented by at least one or several cases without any pelvis fracture. Corridors were constructed for the external forces and the PMHS kinematics. They are provided in this paper as new experimental references to assess the biofidelity of small female human surrogates in different configurations where submarining did or did not occur.

Relation Between Sacroilium and Other Pelvic Fractures Based on Real-World Automotive Accidents.

The study firstly aimed at looking whether sacroilium (SI) fractures could be sustained as unique pelvic injuries in side impact real world automotive accidents. Secondarily, the sacroilium fractures observed in conjunction with other pelvic fractures were analyzed to investigate the existence of injury association patterns. Two real world accident databases were searched for SI fractures. The occupants selected were front car passengers older than 16, involved in side, oblique or frontal impact, with AIS2+ pelvic injuries. In frontal impact, only the belted occupants were selected. The cases were sorted by the principal direction of force (dof) and the type of pelvic injury, namely SI, pubic rami, iliac wing, acetabulum, pubic symphysis, and sacrum injuries. The relation between SI and pubic rami injuries were investigated first. The first database is an accident database composed of cases collected in France by car manufacturers over a period of approximately 40 years. In total it contains approximately 28 000 occupants involved in all types of accident configurations. The occupant injuries, as well as the vehicle deformations, are described in detail. The second database gathered accident cases from 7 zones monitored in Great Britain over a period ranging from 1998 to 2005. All the cases collected include at least one towed away vehicle with at least one injured occupant. In total the database contains approximately 15 000 occupants. The occupant injuries are described in details and autopsy reports were screened when available. Results - In the French database, 39 occupants sustained SI fractures. Out of 39 SI fractures, 32 were associated with pubic rami fractures and 5 additional were associated with other pelvis ring fractures. In the UK database, 46 occupants sustained SI fractures. Out of 46 SI fractures, 34 were associated with pubic rami fractures and 8 additional were associated with other pelvis ring fractures. In side impact (dof 2, 3, 4, 8, 9 or 10 o'clock), in the cases where the side is known for both the SI fractures and pelvic ring injuries, both injuries were on the same side in 70% of the cases. Overall, out of 85 SI fractures cases, only one was clearly identified as occurring with no other pelvic injury and 3 with pelvic injuries other than pelvic ring injury. Conclusions - Overall, from the real world automotive accidents selected at any dof, SI fractures were observed to be associated with other pelvic ring fractures in 96% of the cases. On the reverse, in side impact (dof 2, 3, 4, 8, 9 or 10 o'clock in the LAB database), 89% of the pubic rami fractures occurred without any SI fractures. From a mechanical standing point, it suggests that the SI fractures is a structure more resistant than the rest of the pelvic ring. Overall, 70% of SI fractures were observed in various types of side impacts and 30% in frontal impacts.

Preparation and Formation Process of Zn(II)-Coordinated Nanovesicles.

Mixing a glycylglycine lipid and zinc acetate has been reported to form novel supramolecular Zn(II)-coordinated nanovesicles in ethanol. In this study, we investigate in detail the formation of nanovesicles by using three lipids at different temperatures and discuss their formation process. The original lipids show extremely low solubilities and appear as plate structures in ethanol. Within a small window of lipid solubility, the formation of lipid-Zn(II) complexes occurs mainly on the solid surfaces of plate structures. Controlling of the lipid solubility by temperature affects the kinetics of complex formation and the subsequent transformation of the complexes into nanovesicles and nanotubes. An improved method of two-step control of temperature is developed for preparing all the three kinds of nanovesicles. We provide new insights into the formation process of nanovesicles based on several control experiments. A tetrahedral lipid-cobalt(II) complex similarly produces nanovesicles, whereas an octahedral complex gives sheet structures. Mixing of zinc acetate with a ß-alanyl-ß-alanine lipid can only give sheet structures, which lack a polyglycine II hydrogen-bond network and induce no morphological changes. We conclude that the formation of the lipid-Zn(II) complexes on solid plate structures, tetrahedral geometry, and polyglycine II hydrogen-bond network in the complexes shall work cooperatively for the formation of Zn(II)-coordinated nanovesicles.

Spectroscopic imaging studies of nanoscale polarity and mass transport phenomena in self-assembled organic nanotubes.

Synthetic organic nanotubes self-assembled from bolaamphiphile surfactants are now being explored for use as drug delivery vehicles. In this work, several factors important to their implementation in drug delivery are explored. All experiments are performed with the nanotubes immersed in ethanol. First, Nile Red (NR) and a hydroxylated Nile Red derivative (NR-OH) are loaded into the nanotubes and spectroscopic fluorescence imaging methods are used to determine the apparent dielectric constant of their local environment. Both are found in relatively nonpolar environments, with the NR-OH molecules preferring regions of relatively higher dielectric constant compared to NR. Unique two-color imaging fluorescence correlation spectroscopy (imaging FCS) measurements are then used along with the spectroscopic imaging results to deduce the dielectric properties of the environments sensed by mobile and immobile populations of probe molecules. The results reveal that mobile NR molecules pass through less polar regions, likely within the nanotube walls, while immobile NR molecules are found in more polar regions, possibly near the nanotube surfaces. In contrast, mobile and immobile NR-OH molecules are found to locate in environments of similar polarity. The imaging FCS results also provide quantitative data on the apparent diffusion coefficient for each dye. The mean diffusion coefficient for the NR dye was approximately two-fold larger than that of NR-OH. Slower diffusion by the latter could result from its additional hydrogen bonding interactions with polar triglycine, amine, and glucose moieties near the nanotube surfaces. The knowledge gained in these studies will allow for the development of nanotubes that are better engineered for applications in the controlled transport and release of uncharged, dipolar drug molecules.

Investigation of Pelvic Injuries on Eighteen Post Mortem Human Subjects Submitted to Oblique Lateral Impacts.

The aim of this study was to investigate the sacroiliac joint injury mechanism. Two test configurations were selected from full scale car crashes conducted with the WorldSID 50th dummy resulting in high sacroiliac joint loads and low pubic symphysis force, i.e. severe conditions for the sacroiliac joint. The two test conditions were reproduced in laboratory using a 150-155 kg guided probe propelled respectively at 8 m/s and 7.5 m/s and with different shapes and orientations for the plate impacting the pelvis. Nine Post Mortem Human Subject (PMHS) were tested in each of the two configurations (eighteen PMHS in total). In order to get information on the time of fracture, eleven strain gauges were glued on the pelvic bone of each PMHS. Results - In the first configuration, five PMHS out of nine sustained AIS2+ pelvic injuries. All five presented sacroiliac joint injuries associated with pubic area injuries. In the second configuration, four specimens out of nine sustained AIS2+ pelvic injuries. Two of them presented sacroiliac joint fractures associated with pubic area injuries. The other two presented injuries at the pubic area and acetabulum only. The strain gauges signals suggested that the pubic fractures occurred before the sacroiliac joint fractures in the great majority of the cases (five cases out of seven). Conclusions - Even in the oblique impact conditions of the present study, the pubic symphysis area was observed to be the weakest zone of the pelvis and its failure the predominant cause of sacroiliac joint injuries. It was hypothesized that the failure of the pubic rami allowed the hemi-pelvis to rotate inward, and that this closing-book motion induced the failure of the sacroiliac joint.

Zn-Coordinated Lipid Nanocapsules with High Physical Stability and Water-Responsive Morphological Change.

A novel lipid nanocapsule with high physical stability and the ability to undergo a water-responsive morphological change was prepared using a facile method from inexpensive and simple materials such as a glycylglycine-containing lipid and zinc acetate. The zinc-coordinated nanocapsule is comprised of solid bilayer membranes, which are stabilized by polyglycine-II type hydrogen-bond network and Zn-lipid coordination resulting in a high thermal stability in the dry state. The nanocapsules can easily encapsulate guest molecules such as methylene blue in the hollow space by dissolving the molecules in ethanol during preparation. When placed in an aqueous environment, the nanocapsules showed distinctive morphological changes and subsequent release of the methylene blue.

Imaging fluorescence correlation spectroscopy studies of dye diffusion in self-assembled organic nanotubes.

The rate and mechanism of diffusion by anionic sulforhodamine B (SRB) dye molecules within organic nanotubes self-assembled from bolaamphiphile surfactants were investigated by imaging fluorescence correlation spectroscopy (imaging-FCS). The inner and outer surfaces of the nanotubes are terminated with amine and glucose groups, respectively; the former allow for pH-dependent manipulation of nanotube surface charge while the latter enhance their biocompatibility. Wide-field fluorescence video microscopy was used to locate and image dye-doped nanotubes dispersed on a glass surface. Imaging-FCS was then used to spatially resolve the SRB transport dynamics. Mobilization of the dye molecules was achieved by immersion of the nanotubes in buffer solution. Experiments were performed in pH 6.4, 7.4 and 8.4 buffers, at ionic strengths ranging from 1.73 mM to 520 mM. The results show that coulombic interactions between cationic ammonium ions on the inner nanotube surface and the anionic SRB molecules play a critical role in governing mass transport of the dye. The apparent dye diffusion coefficient, D, was found to generally increase with increasing ionic strength and with increasing pH. The D values obtained were found to be invariant along the nanotube length. Mass transport of the SRB molecules within the nanotubes is concluded to occur by a desorption-mediated Fickian diffusion mechanism in which dye motion is slowed by its coulombic interactions with the inner surfaces of the nanotubes. The results of these studies afford information essential to the use of organic nanotubes in controlled drug release applications.

Supramolecular Self-Assembly into Biofunctional Soft Nanotubes: From Bilayers to Monolayers.

The inner and outer surfaces of bilayer-based lipid nanotubes can be hardly modified selectively by a favorite functional group. Monolayer-based nanotubes display a definitive difference in their inner and outer functionalities if bipolar wedge-shaped amphiphiles, so-called bolaamphiphiles, as a constituent of the monolayer membrane pack in a parallel fashion with a head-to-tail interface. To exclusively form unsymmetrical monolayer lipid membranes, we focus herein on the rational molecular design of bolaamphiphiles and a variety of self-assembly processes into tubular architectures. We first describe the importance of polymorph and polytype control and then discuss diverse methodologies utilizing a polymer template, multiple hydrogen bonds, binary and ternary coassembly, and two-step self-assembly. Novel biologically important functions of the obtained soft nanotubes, brought about only by completely unsymmetrical inner and outer surfaces, are discussed in terms of protein refolding, drug nanocarriers, lectin detection, a chiral inducer for achiral polymers, the tailored fabrication of polydopamine, and spontaneous nematic alignment.

Molecular-Level Understanding of the Encapsulation and Dissolution of Poorly Water-Soluble Ibuprofen by Functionalized Organic Nanotubes Using Solid-State NMR Spectroscopy.

A comprehensive study of the encapsulation and dissolution of the poorly water-soluble drug ibuprofen (IBU) using two types of organic nanotubes (ONT-1 and ONT-2) was conducted. ONT-1 and ONT-2 had similar inner and outer diameters, but these surfaces were functionalized with different groups. IBU was encapsulated by each ONT via solvent evaporation. The amount of IBU in the ONTs was 9.1 and 29.2 wt % for ONT-1 and ONT-2, respectively. Dissolution of IBU from ONT-1 was very rapid, while from ONT-2 it was slower after the initial burst release. One-dimensional (1D) (1)H, (13)C, and two-dimensional (2D) (1)H-(13)C solid-state NMR measurements using fast magic-angle spinning (MAS) at a rate of 40 kHz revealed the molecular state of the encapsulated IBU in each ONT. Extremely mobile IBU was observed inside the hollow nanosapce of both ONT-1 and ONT-2 using (13)C MAS NMR with a single pulse (SP) method. Interestingly, (13)C cross-polarization (CP) MAS NMR demonstrated that IBU also existed on the outer surface of both ONTs. The encapsulation ratios of IBU inside the hollow nanospaces versus on the outer surfaces were calculated by waveform separation to be approximately 1:1 for ONT-1 and 2:1 for ONT-2. Changes in (13)C chemical shifts showed the intermolecular interactions between the carboxyl group of IBU and the amino group on the ONT-2 inner surface. The cationic ONT-2 could form the stronger electrostatic interactions with IBU in the hollow nanosapce than anionic ONT-1. On the other hand, 2D (1)H-(13)C NMR indicated that the hydroxyl groups of the glucose unit on the outer surface of the ONTs interacted with the carboxyl group of IBU in both ONT-1 and ONT-2. The changes in peak shape and chemical shift of the ONT glucose group after IBU encapsulation were larger in ONT-2 than in ONT-1, indicating a stronger interaction between IBU and the outer surface of ONT-2. The smaller amount of IBU encapsulation and rapid IBU dissolution from ONT-1 could be due to the weak interactions both at the outer and inner surfaces. Meanwhile, the stronger interaction between IBU and the inner surface of ONT-2 could suppress IBU dissolution, although the IBU on the outer surface of ONT-2 was released soon after dispersal in water. This study demonstrates that the encapsulation amount and the dissolution rates of poorly water-soluble drugs, a class which makes up the majority of new drug candidates, can be controlled using the functional groups on the surfaces of ONTs by considering the host-guest interactions.

Effect of Photoinduced Size Changes on Protein Refolding and Transport Abilities of Soft Nanotubes.

Self-assembly of azobenzene-modified amphiphiles (Glyn Azo, n=1-3) in water at room temperature in the presence of a protein produced nanotubes with the protein encapsulated in the channels. The Gly2 Azo nanotubes (7 nm internal diameter [i.d.]) promoted refolding of some encapsulated proteins, whereas the Gly3 Azo nanotubes (13 nm i.d.) promoted protein aggregation. Although the 20 nm i.d. channels of the Gly1 Azo nanotubes were too large to influence the encapsulated proteins, narrowing of the i.d. to 1 nm by trans-to-cis photoisomerization of the azobenzene units of the Gly1 Azo monomers packed in the solid bilayer membranes led to a squeezing out of the proteins into the bulk solution and simultaneously enhanced their refolding ratios. In contrast, photoinduced transformation of the Gly2 Azo nanotubes to short nanorings (<40 nm) with a large i.d. (28 nm) provided no further refolding assistance. We thus demonstrate that pertubation by the solid bilayer membrane wall of the nanotubes is important to accelerate refolding of the denatured proteins during their transport in the narrow nanotube channels.

Lipid Nanotube Tailored Fabrication of Uniquely Shaped Polydopamine Nanofibers as Photothermal Converters.

Helically coiled and linear polydopamine (PDA) nanofibers were selectively fabricated with two different types of lipid nanotubes (LNTs) that acted as templates. The obtained coiled PDA-LNT hybrid showed morphological advantages such as higher light absorbance and photothermal conversion effect compared to a linear counterpart. Laser irradiation of the coiled PDA-LNT hybrid induced a morphological change and subsequent release of the encapsulated guest molecule. In cellular experiments, the coiled PDA-LNT efficiently eliminated HeLa cells because of its strong affinity with the tumor cells. This work illustrates the first approach to construct characteristic morphologies of PDA nanofibers using LNTs as simple templates, and the coiled PDA-LNT hybrid exhibits attractive photothermal features derived from its unique coiled shape.

Soft nanotubes acting as confinement effecters and chirality inducers for achiral polythiophenes.

Depending on their nanochannel sizes, soft nanotubes were able to not only control the conformation and aggregation state of encapsulated achiral polythiophene boronic acids but also induce chirality in the polythiophene chains that exhibit chiral recognition abilities for D, L-sugars.

A Comparison of Sacroiliac and Pubic Rami Fracture Occurrences in Oblique Side Impact Tests on Nine Post Mortem Human Subjects.

UNLABELLED: The WorldSID dummy can be equipped with both a pubic and a sacroiliac joint (S-I joint) loadcell. Although a pubic force criterion and the associated injury risk curve are currently available and used in regulation (ECE95, FMVSS214), as of today injury mechanisms, injury criteria, and injury assessment reference values are not available for the sacroiliac joint itself. The aim of this study was to investigate the sacroiliac joint injury mechanism. Three configurations were identified from full-scale car crashes conducted with the WorldSID 50th percentile male where the force passing through the pubis in all three tests was approximately 1500 N while the sacroiliac Fy/Mx peak values were 4500 N/50 Nm, 2400 N/130 Nm, and 5300 N/150 Nm, respectively. These tests were reproduced using a 150 kg guided probe impacting Post Mortem Human Subjects (PMHS) at 8 m/s, 5.4 m/s and 7.5 m/s. The shape and the orientation of the impacting face of the probe were selected to match the WorldSID pubic Fy and sacroiliac Fy/Mx loads of the three vehicle test configurations. Three PMHS were tested in each of the three configurations (nine PMHS in total). RESULTS: In the first PMHS configuration, one specimen sustained an AIS 3 injury and one sustained an AIS 4 injury (an unstable pelvis with complete disruption of the posterior arch, a sacroiliac joint disruption associated with an iliac fracture, and a pubic symphysis separation). In the second configuration, all specimens sustained a fracture of the superior lateral iliac wing (AIS 2). In the third configuration, one specimen sustained a partial disruption of the anterior arch (AIS 2). Based on the data from strain gauges located on the pubic rami and near the sacroiliac joint, the pubic rami fractures were identified as occurring prior to the sacroiliac fractures. CONCLUSIONS: Out of nine impactor tests performed, the PMHS S-I joint injuries were observed to consistently be associated with pelvic anterior arch fractures. In addition, from the injury sequences derived from strain gauges located on the specimen pelvises and on the injury assessments obtained by necropsy, the S-I joint fractures were observed to occur after the anterior arch fractures.

Reference PMHS Sled Tests to Assess Submarining.

Sled tests focused on pelvis behavior and submarining can be found in the literature. However, they were performed either with rigid seats or with commercial seats. The objective of this study was to get reference tests to assess the submarining ability of dummies in more realistic conditions than on rigid seat, but still in a repeatable and reproducible setup. For this purpose, a semi-rigid seat was developed, which mimics the behavior of real seats, although it is made of rigid plates and springs that are easy to reproduce and simulate with an FE model. In total, eight PMHS sled tests were performed on this semirigid seat to get data in two different configurations: first in a front seat configuration that was designed to prevent submarining, then in a rear seat configuration with adjusted spring stiffness to generate submarining. All subjects sustained extensive rib fractures from the shoulder belt loading. No pelvis fractures and no submarining were observed in the front seat configuration, but two subjects sustained lumbar vertebrae fractures. In the rear seat configuration, all subjects sustained pelvic fractures and demonstrated submarining. Corridors were constructed for the external forces and the PMHS kinematics. They are provided in this paper as new reference tests to assess the biofidelity of human surrogates in different configurations that either result in submarining or do not. In future, it is intended to analyze further seat and restraint system configurations to be able to define a submarining predictor.

Qualitative/chiral sensing of amino acids by naked-eye fluorescence change based on morphological transformation and hierarchizing in supramolecular assemblies of pyrene-conjugated glycolipids.

Supramolecular assemblies of fluorescent glycolipids exhibited molecular packing rearrangement as well as morphological transformation, in response to amino acid analytes. Naked-eye detectable fluorescence color changes and hydrogel formation as the result of the amplification of the molecular- and nanometer-scaled changes enabled not only qualitative analysis but also chiral sensing of a specific amino acid among 20 amino acids.