Transport properties of dense fluid argon

We calculate using molecular dynamics simulations the transport properties of realistically modeled fluid argon at pressures up to $\simeq 50GPa$ and temperatures up to $3000K$. In this context we provide a critique of some newer theoretical predictions for the diffusion coefficients of liquids and a discussion of the Enskog theory relevance under two different adaptations: modified Enskog theory (MET) and effective diameter Enskog theory. We also analyze a number of experimental data for the thermal conductivity of monoatomic and small diatomic dense fluids.Comment: 8 pages, 6 figure

Impact of Software Modeling on the Accuracy of Perfusion MRI in Glioma

PURPOSE: To determine whether differences in modeling implementation will impact the correction of leakage effects (from blood brain barrier disruption) and relative cerebral blood volume (rCBV) calculations as measured on T2*-weighted dynamic susceptibility-weighted contrast-enhanced (DSC)-MRI at 3T field strength. MATERIALS AND METHODS: This HIPAA-compliant study included 52 glioma patients undergoing DSC-MRI. Thirty-six patients underwent both non Preload Dose (PLD) and PLD-corrected DSC acquisitions, with sixteen patients undergoing PLD-corrected acquisitions only. For each acquisition, we generated two sets of rCBV metrics using two separate, widely published, FDA-approved commercial software packages: IB Neuro (IBN) and NordicICE (NICE). We calculated 4 rCBV metrics within tumor volumes: mean rCBV, mode rCBV, percentage of voxels with rCBV > 1.75 (%>1.75), and percentage of voxels with rCBV > 1.0 (Fractional Tumor Burden or FTB). We determined Pearson (r) and Spearman (ρ) correlations between non-PLD- and PLD-corrected metrics. In a subset of recurrent glioblastoma patients (n=25), we determined Receiver Operator Characteristic (ROC) Areas-Under-Curve (AUC) for FTB accuracy to predict the tissue diagnosis of tumor recurrence versus post-treatment effect (PTRE). We also determined correlations between rCBV and microvessel area (MVA) from stereotactic biopsies (n=29) in twelve patients. RESULTS: Using IBN, rCBV metrics correlated highly between non-PLD- and PLD-corrected conditions for FTB (r=0.96, ρ=0.94), %>1.75 (r=0.93, ρ=0.91), mean (r=0.87, ρ=0.86) and mode (r=0.78, ρ=0.76). These correlations dropped substantially with NICE. Using FTB, IBN was more accurate than NICE in diagnosing tumor vs PTRE (AUC=0.85 vs 0.67) (p<0.01). The highest rCBV-MVA correlations required PLD and IBN (r=0.64, ρ=0.58, p=0.001). CONCLUSIONS: Different implementations of perfusion MRI software modeling can impact the accuracy of leakage correction, rCBV calculation, and correlations with histologic benchmarks

Changes in five-year survival for people with acute leukaemia in South Australia, 1980-2016

First published: 16 February 2022Objectives: To examine population changes in 5-year survival for people in South Australia diagnosed with acute leukaemia during 1980–2016, by socio-demographic characteristics. Design, setting: Retrospective analysis of South Australian Cancer Registry data for the period 1980–2016. Participants: All South Australian residents diagnosed with primary acute lymphoblastic leukaemia (ALL) or acute myeloid leukaemia (AML) during 1980–2016. Main outcome measures: 5-year disease-specific survival and disease-specific mortality. Results: Crude 5-year disease-specific survival was 58% (95% CI, 54–61%) for the 1035 people diagnosed with ALL during 1980–2016, and 18% (95% CI, 17–20%) for the 2814 people diagnosed with AML. Survival improved steadily across the study period: from 44% (95% CI, 35–52%) for people with ALL diagnosed during 1980–1984 to 69% (95% CI, 63–75%) for those diagnosed during 2010–2016; and from 9% (95% CI, 5–15%) to 23% (95% CI, 20–26%) for people diagnosed with AML. Disease-specific mortality increased with age, but was not influenced by socio-economic status or remoteness of residence. After adjusting for other factors, rates of change in risk of leukaemia-related death were greater for younger than older patients with ALL (for interaction: P = 0.004) or AML (P = 0.005), but were not significantly influenced by socio-economic status or remoteness. Conclusion: Five-year survival for people with acute leukaemia in South Australia continuously improved during 1980–2016, and socio-economic status and remoteness did not influence survival. It improved markedly for younger patients (under 50 years of age). However, survival is still relatively poor, especially for people over 50 years with AML.Kerri Beckmann, Brendon J Kearney, David Yeung, Devendra Hiwase, Ming Li, David M Rode