A Unified Theoretical Description of the Thermodynamical Properties of Spin Crossover with Magnetic Interactions

After the discovery of the phenomena of light-induced excited spin state trapping (LIESST), the functional properties of metal complexes have been studied intensively. Among them, cooperative phenomena involving low spin-high spin (spin-crossover) transition and magnetic ordering have attracted interests, and it has become necessary to formulate a unified description of both phenomena. In this work, we propose a model in which they can be treated simultaneously by extending the Wajnflasz-Pick model including a magnetic interaction. We found that this new model is equivalent to Blume-Emery-Griffiths (BEG) Hamiltonian with degenerate levels. This model provides a unified description of the thermodynamic properties associated with various types of systems, such as spin-crossover (SC) solids and Prussian blue analogues (PBA). Here, the high spin fraction and the magnetization are the order parameters describing the cooperative phenomena of the model. We present several typical temperature dependences of the order parameters and we determine the phase diagram of the system using the mean-field theory and Monte Carlo simulations. We found that the magnetic interaction drives the SC transition leading to re-entrant magnetic and first-order SC transitions.Comment: 30pages, 11figure

Differences in risk factors between early and late trauma death after road traffic accidents

We aimed to determine the differences in risk factors between early and late trauma death after road traffic accidents. We identified road traffic accident victims from our trauma registry. We defined death that occurred within five days after an accident and death that occurred between 6 and 30 days as early and late trauma death, respectively. We derived two logistic regression models by using early or late trauma death as an outcome measure. We considered a variable significant at the 5% level; significant variables were considered risk factors for early and/or late trauma death. Overall, there were 1,201 victims; 134 and 29 patients experienced early and late trauma death, respectively. The common risk factors for both early and late trauma death included age, Glasgow Coma Scale and systolic blood pressure. We found that the NISS was not a risk factor for late trauma death, although the NISS was a risk factor for early trauma death. Road traffic accident victims aged 65 years or older and/or with a depressed level of consciousness were at increased risk of late trauma death, even if the victims had a low anatomical severity level and survived their first five days after an accident

Comparisons of the outcome prediction performance of injury severity scoring tools using the abbreviated injury scale 90 update 98 (AIS 98) and 2005 update 2008 (AIS 2008)

The Abbreviated Injury Scale (AIS) was revised in 2005 and updated in 2008 (AIS 2008). We aimed to compare the outcome prediction performance of AIS-based injury severity scoring tools by using AIS 2008 and AIS 98. We used all major trauma patients hospitalized to the Royal Perth Hospital between 1994 and 2008. We selected five AIS-based injury severity scoring tools, including Injury Severity Score (ISS), New Injury Severity Score (NISS), modified Anatomic Profile (mAP), Trauma and Injury Severity Score (TRISS) and A Severity Characterization of Trauma (ASCOT). We selected survival after injury as a target outcome. We used the area under the Receiver Operating Characteristic curve (AUROC) as a performance measure. First, we compared the five tools using all cases whose records included all variables for the TRISS (complete dataset) using a 10-fold cross-validation. Second, we compared the ISS and NISS for AIS 98 and AIS 2008 using all subjects (whole dataset). We identified 1,269 and 4,174 cases for a complete dataset and a whole dataset, respectively. With the 10-fold cross-validation, there were no clear differences in the AUROCs between the AIS 98- and AIS 2008-based scores. With the second comparison, the AIS 98-based ISS performed significantly worse than the AIS 2008-based ISS (p<0.0001), while there was no significant difference between the AIS 98- and AIS 2008-based NISSs. Researchers should be aware of these findings when they select an injury severity scoring tool for their studies. ©Annals of Advances in Automotive Medicine

Trends in traumatic out-of-hospital cardiac arrest in Perth, Western Australia from 1997 to 2014

Aim: This study aims to describe and compare traumatic and medical out-of-hospital cardiac arrest (OHCA) occurring in Perth, Western Australia, between 1997 and 2014. Methods: The St John Ambulance Western Australia (SJA-WA) OHCA Database was used to identify all adult (≥16 years) cases. We calculated annual crude and age-sex standardised incidence rates (ASIRs) for traumatic and medical OHCA and investigated trends over time. Results: Over the study period, SJA-WA attended 1,354 traumatic OHCA and 16,076 medical OHCA cases. The mean annual crude incidence rate of traumatic OHCA in adults attended by SJA-WA was 6.0 per 100,000 (73.9 per 100,000 for medical cases), with the majority resulting from motor vehicle collisions (56.7%). We noted no change to either incidence or mechanism of injury over the study period (p > 0.05). Compared to medical OHCA, traumatic OHCA cases were less likely to receive bystander cardiopulmonary resuscitation (CPR) (20.4% vs. 24.5%, p = 0.001) or have resuscitation commenced by paramedics (38.9% vs. 44.8%, p < 0.001). However, rates of bystander CPR and resuscitation commenced by paramedics increased significantly over time in traumatic OHCA (p < 0.001). In cases where resuscitation was commenced by paramedics there was no difference in the proportion who died at the scene (37.2% traumatic vs. 34.3% medical, p = 0.17), however, fewer traumatic OHCAs survived to hospital discharge (1.7% vs. 8.7%, p < 0.001). Conclusions: Despite temporal increases in rates of bystander CPR and paramedic resuscitation, traumatic OHCA survival remains poor with only nine patients surviving from traumatic OHCA over the 18-year period