Deterministic multi-zone ice accretion modeling

The focus here is on a deterministic model of the surface roughness transition behavior of glaze ice. The initial smooth/rough transition location, bead formation, and the propagation of the transition location are analyzed. Based on the hypothesis that the smooth/rough transition location coincides with the laminar/turbulent boundary layer transition location, a multizone model is implemented in the LEWICE code. In order to verify the effectiveness of the model, ice accretion predictions for simple cylinders calculated by the multizone LEWICE are compared to experimental ice shapes. The glaze ice shapes are found to be sensitive to the laminar surface roughness and bead thickness parameters controlling the transition location, while the ice shapes are found to be insensitive to the turbulent surface roughness

The Role of Local Policies on Resource Utilization: Timber Harvesting in St. Tammany Parish, Louisiana

Seemingly unrelated regression was used to investigate if the passage of forestry-related ordinances has had an effect upon timber harvesting activities in St. Tammany Parish, Louisiana. Results indicate that a significant negative relationship exists between a $10,000 road bond ordinance and the level of timber harvest in the Parish.Resource /Energy Economics and Policy,

Combined statistical and hydrodynamic modelling of compound flooding in coastal areas - Methodology and application

This paper presents a robust cost-effective framework for assessment of coastal-fluvial flooding due to compound action of multivariate dependent drivers. The methodology is an 8-step process that links statistical and hydrodynamic models to determine probabilities of multiple-driver flood events and associated hazards. The method involves individual and combined extreme value analysis, assessment of dependencies and interactions between flood drivers, multivariate joint probability determination accounting for dependencies, high-resolution hydrodynamic modelling of flood scenarios derived from multivariate statistical analysis, and ultimately mapping of inundation. Using Cork City, on the south coast of Ireland, as a study case, the research shows that the interactions and dependencies between tides, surges and river flows affect flood severity when they occur jointly. Tide-surge interactions have a damping effect on the total water level, while dependence between the surge residual and river flow amplifies the risk of flooding. The multivariate joint exceedance probability occurrence of high discharges and water levels represents a more realistic representation of the spatially variable water surface profiles then the combined univariate marginal scenarios. Multivariate analysis allows also considering multiple combinations of joint probability solutions along RP iso-curves. The results show that the quantification of compound flood impacts must be performed along the entire RP probability curve. This is because the physical/hydrological impacts of multiple-driver same-RP flood events can be very different leading to substantially different characteristics of flooding. The multi-scale nested flood model (MSN_Flood) was used to simulate flood wave propagation over urban floodplains for an ensemble of statistically derived flood scenarios. The hydrodynamic runs provide inundation maps that can be used to draw inferences about flood mechanisms and impacts. Multivariate analysis allows also considering multiple combinations of joint probability solutions along a RP iso-curve. While the RPs iso-curve represents the joint events of the same exceedance probability, the physical/hydrological impact of such events can be very different leading to substantially different characteristics of flooding. For these reasons combining the statistical and hydrodynamic modelling is very important

Neuronal injury biomarkers for assessment of the individual cognitive reserve in clinically suspected Alzheimer's disease

Objectives: Many predictive or influencing factors have emerged in investigations of the cognitive reserve model of patients with Alzheimer's disease (AD). For example, neuronal injury, which correlates with cognitive decline in AD, can be assessed by [F-18]-fluorodeoxyglucose positron-emission-tomography (FDG-PET), structural magnetic resonance imaging (MRI) and total tau in cerebrospinal fluid (CSFt-tau), all according to the A/T/N-classification. The aim of this study was to calculate residual cognitive performance based on neuronal injury biomarkers as a surrogate of cognitive reserve, and to test the predictive value of this index for the individual clinical course. Methods: 110 initially mild cognitive impaired and demented subjects (age 71 +/- 8 years) with a final diagnosis of AD dementia were assessed at baseline by clinical mini-mental-state-examination (MMSE), FDG-PET, MRI and CSFt-tau. All neuronal injury markers were tested for an association with clinical MMSE and the resulting residuals were correlated with years of education. We used multiple regression analysis to calculate the expected MMSE score based on neuronal injury biomarkers and covariates. The residuals of the partial correlation for each biomarker and the predicted residualized memory function were correlated with individual cognitive changes measured during clinical follow-up (27 +/- 13 months). Results: FDG-PET correlated highly with clinical MMSE (R = - 0.49, p < .01), whereas hippocampal atrophy to MRI (R = -0.15, p = .14) and CSFt-tau, (R = -0.12, p = .22) showed only weak correlations. Residuals of all neuronal injury biomarker regressions correlated significantly with education level, indicating them to be surrogates of cognitive reserve. A positive residual was associated with faster cognitive deterioration at follow-up for the residuals of stand-alone FDG-PET (R = - 0.36, p = .01) and the combined residualized memory function model (R = - 0.35, p = .02). Conclusions: These findings suggest that subjects with higher cognitive reserve had accumulated more pathology, which subsequently caused a faster cognitive decline over time. Together with previous findings suggesting that higher reserve is associated with slower cognitive decline, we propose a biphasic reserve effect, with an initially protective phase followed by more rapid decompensation once the protection is overwhelmed

Correlation of Perfusion MRI and F-18-FDG PET Imaging Biomarkers for Monitoring Regorafenib Therapy in Experimental Colon Carcinomas with Immunohistochemical Validation

Objectives To investigate a multimodal, multiparametric perfusion MRI/F-18-fluoro-deoxyglucose (F-18-FDG)-PET imaging protocol for monitoring regorafenib therapy effects on experimental colorectal adenocarcinomas in rats with immunohistochemical validation. Materials and Methods Human colorectal adenocarcinoma xenografts (HT-29) were implanted subcutaneously in n = 17 (n = 10 therapy group;n = 7 control group) female athymic nude rats (Hsd: RH-Foxn1(mu)). Animals were imaged at baseline and after a one-week daily treatment protocol with regorafenib (10 mg/kg bodyweight) using a multimodal, multiparametric perfusion MRI/F-18-FDG-PET imaging protocol. In perfusion MRI, quantitative parameters of plasma flow (PF, mL/100 mL/min), plasma volume (PV,%) and endothelial permeability-surface area product (PS, mL/100 mL/min) were calculated. In F-18-FDG-PET, tumor-to-background-ratio (TTB) was calculated. Perfusion MRI parameters were correlated with TTB and immunohistochemical assessments of tumor microvascular density (CD-31) and cell proliferation (Ki-67). Results Regorafenib significantly (p<0.01) suppressed PF (81.1 +/- 7.5 to 50.6 +/- 16.0 mL/100mL/min), PV (12.1 +/- 3.6 to 7.5 +/- 1.6%) and PS (13.6 +/- 3.2 to 7.9 +/- 2.3 mL/100mL/min) as well as TTB (3.4 +/- 0.6 to 1.9 +/- 1.1) between baseline and day 7. Immunohistochemistry revealed significantly (p<0.03) lower tumor microvascular density (CD-31, 7.0 +/- 2.4 vs. 16.1 +/- 5.9) and tumor cell proliferation (Ki-67, 434.0 +/- 62.9 vs. 663.0 +/- 98.3) in the therapy group. Perfusion MRI parameters Delta PF, Delta PV and Delta PS showed strong and significant (r = 0.67-0.78;p<0.01) correlations to the PET parameter Delta TTB and significant correlations (r = 0.57-0.67;p<0.03) to immunohistochemical Ki-67 as well as to CD-31-stainings (r = 0.49-0.55;p<0.05). Conclusions A multimodal, multiparametric perfusion MRI/PET imaging protocol allowed for non-invasive monitoring of regorafenib therapy effects on experimental colorectal adenocarcinomas in vivo with significant correlations between perfusion MRI parameters and F-18-FDG-PET validated by immunohistochemistry

Structure and content of the EU-IVDR: current status and implications for pathology

Background Regulation (EU) 2017/746 on in vitro diagnostic medical devices (IVDR) was passed by the European Parliament and the Council of the European Union on 5 April 2017 and came into force on 26 May 2017. A new amending regulation, which introduces a phased implementation of the IVDR with new transitional provisions for certain in vitro diagnostic medical devices (IVDs) and a later date of application of some requirements for in-house devices for healthcare facilities, was adopted on 15 December 2021. The combined use of CE-certified IVDs (CE-IVDs), in-house IVDs (IH-IVDs), and research use only (RUO) devices are a cornerstone of diagnostics in pathology departments and crucial for optimal patient care. The IVDR not only regulates the manufacture and placement on the market of industrially manufactured IVDs, but also imposes conditions on the manufacture and use of IH-IVDs for internal use by healthcare facilities. Objectives Our work provides an overview of the background and structure of the IVDR and identifies core areas that need to be interpreted and fleshed out in the context of the legal framework as well as expert knowledge. Conclusions The gaps and ambiguities in the IVDR crucially require the expertise of professional societies, alliances, and individual stakeholders to successfully facilitate the implementation and use of the IVDR in pathology departments and to avoid aberrant developments

MicroRNA control of podosome formation in vascular smooth muscle cells in vivo and in vitro

PDGF enhances podosome formation and cell migration by regulating expression of the microRNAs miR-143 and -145, which target PDGF-R, PKC-ε, and fascin