Numerical Investigation of the Performance of Kenics Static Mixers for the Agitation of Shear Thinning Fluids

The laminar flow of non-Newtonian fluids through a Kenics static mixer is investigated by using the CFD (Computational Fluid Dynamics) tool. The working fluids have a shear thinning behavior modeled by the Ostwald De Waele law. We focus on the effect of Reynolds number, fluid properties, twist angle and blade pitch on the flow characteristics and energy cost. The pressure drop information obtained from the simulations was compared to several experimental correlations and data available in the literature. The numerical results were found in good agreement with the experimental values. From the obtained results, the twist technique is confirmed to be very useful to enhance the mixing with less power consumption and at low Reynolds numbers. A faster axial mixing has been achieved with increased blade length and decreased twist angle. However, the good mixing near the tube walls was obtained with increased twist angle. The power consumption expressed in power drop was found to be increase with increased CMC concentrations, Reynolds number, twist angle and decreased blade length

A systematic review of risk assessment tools for contaminated sites – Current perspectives and future prospects

© 2020 Elsevier Inc. Health and safety hazards associated with the redevelopment of contaminated sites can be complex and pose considerable risks. A systematic literature review was conducted on risk assessment tools for contaminated sites. These tools have been identified from searching through leading academic databases and other professional sources. For each of the identified tools the relevant risk assessment stages, harm type, hazard category, receptor type and pathways are reported. Findings reveal that despite growing interest in the development of risk assessment tools, there are persistent knowledge gaps identified in this study, which serve as a basis for future research direction to where more advanced practical tools could be invented. For instance, it is evidenced there is a shortfall in practical tools available to contaminated site assessors conducting investigations at the preliminary risk assessment stage. Addressing this opening can benefit the planning process, coordinated between relevant stakeholders and, moreover, reduce uncertainty in the decision-making of contaminated site developers

Epigenetic modulators as therapeutic targets in prostate cancer

Prostate cancer is one of the most common non-cutaneous malignancies among men worldwide. Epigenetic aberrations, including changes in DNA methylation patterns and/or histone modifications, are key drivers of prostate carcinogenesis. These epigenetic defects might be due to deregulated function and/or expression of the epigenetic machinery, affecting the expression of several important genes. Remarkably, epigenetic modifications are reversible and numerous compounds that target the epigenetic enzymes and regulatory proteins were reported to be effective in cancer growth control. In fact, some of these drugs are already being tested in clinical trials. This review discusses the most important epigenetic alterations in prostate cancer, highlighting the role of epigenetic modulating compounds in pre-clinical and clinical trials as potential therapeutic agents for prostate cancer management.info:eu-repo/semantics/publishedVersio

Direct bandgap silicon through strain engineering of type-VIII silicon clathrate Si46: A first-principles study

2-s2.0-85083164243In this work, we suggest a way to achieve a direct bandgap silicon clathrate by means of first-principles calculations. Effects of biaxial-strain on physical properties of type-VIII silicon clathrate Si46 are investigated. For that purpose, biaxial strain tensors (?4%<? <+6%) have been exerted along the <100> and <010> in-plane directions, while the out-of-plane <001> axis is strain-free. Under normal conditions, type-VIII Si46 is indirect bandgap semiconductor with magnitude of about 1.152eV (GGA-PBE). For sake of comparison, the band structure was as well calculated by means of the hybrid PBE0 functional, in that case its allure and nature were not affected, whereas the bandgap's magnitude was increased to 2.62eV (Hybrid PBE0). It was observed that a tensile strain of +4% and above will induce a bandgap alteration from indirect to direct where both the conduction band minimum CBM and the valence band maximum VBM are located at the same point within the ?(0,0,0)–H(1/2,1/2,-1/2) symmetry segment (?). Optical properties revealed better spectrums for the +4% strained material with direct bandgap as the optical light absorption was increased by about 12%. These findings play in favor for this material as a candidate for future “all-Si” photonic and photovoltaic devices. © 2020 Elsevier B.V

Intérêt de l’acquisition précoce lors d’un examen TEP-PSMA marqué au gallium 68 dans le cadre du bilan de récidive biochimique d’un cancer de prostate

International audienc

Complications in COVID-19 patients: Characteristics of pulmonary embolism

Objective: The purpose of this study is to evaluate chest CT imaging features, clinical characteristics, laboratory values of COVID-19 patients who underwent CTA for suspected pulmonary embolism. We also examined whether clinical, laboratory or radiological characteristics could be associated with a higher rate of PE. Materials and methods: This retrospective study included 84 consecutive patients with laboratory-confirmed SARS-CoV-2 who underwent CTA for suspected PE. The presence and localization of PE as well as the type and extent of pulmonary opacities on chest CT exams were examined and correlated with the information on comorbidities and laboratory values for all patients. Results: Of the 84 patients, pulmonary embolism was discovered in 24 patients. We observed that 87% of PE was found to be in lung parenchyma affected by COVID-19 pneumonia. Compared with no-PE patients, PE patients showed an overall greater lung involvement by consolidation (p = 0.02) and GGO (p < 0.01) and a higher level of D-Dimer (p < 0,01). Moreover, the PE group showed a lower level of saturation (p = 0,01) and required more hospitalization (p < 0,01). Conclusion: Our study showed a high incidence of PE in COVID-19 pneumonia. In 87% of patients, PE was found in lung parenchyma affected by COVID-19 pneumonia with a worse CT severity score and a greater number of lung lobar involvement compared with non-PE patients. CT severity, lower level of saturation, and a rise in D-dimer levels could be an indication for a CTPA. Advances in knowledge: Certain findings of non-contrast chest CT could be an indication for a CTPA

Ipilimumab versus placebo after radiotherapy in patients with metastatic castration-resistant prostate cancer that had progressed after docetaxel chemotherapy (CA184-043): A multicentre, randomised, double-blind, phase 3 trial

Background Ipilimumab is a fully human monoclonal antibody that binds cytotoxic T-lymphocyte antigen 4 to enhance antitumour immunity. Our aim was to assess the use of ipilimumab after radiotherapy in patients with metastatic castration-resistant prostate cancer that progressed after docetaxel chemotherapy.Methods We did a multicentre, randomised, double-blind, phase 3 trial in which men with at least one bone metastasis from castration-resistant prostate cancer that had progressed after docetaxel treatment were randomly assigned in a 1: 1 ratio to receive bone-directed radiotherapy (8 Gy in one fraction) followed by either ipilimumab 10 mg/kg or placebo every 3 weeks for up to four doses. Non-progressing patients could continue to receive ipilimumab at 10 mg/kg or placebo as maintenance therapy every 3 months until disease progression, unacceptable toxic effect, or death. Patients were randomly assigned to either treatment group via a minimisation algorithm, and stratified by Eastern Cooperative Oncology Group performance status, alkaline phosphatase concentration, haemoglobin concentration, and investigator site. Patients and investigators were masked to treatment allocation. The primary endpoint was overall survival, assessed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT00861614.Findings From May 26, 2009, to Feb 15, 2012, 799 patients were randomly assigned (399 to ipilimumab and 400 to placebo), all of whom were included in the intention-to-treat analysis. Median overall survival was 11.2 months (95% CI 9.5-12.7) with ipilimumab and 10.0 months (8.3-11.0) with placebo (hazard ratio [HR] 0.85, 0.72-1.00; p=0.053). However, the assessment of the proportional hazards assumption showed that it was violated (p=0.0031). A piecewise hazard model showed that the HR changed over time: the HR for 0-5 months was 1.46 (95% CI 1.10-1.95), for 5-12 months was 0.65 (0.50-0.85), and beyond 12 months was 0.60 (0.43-0.86). The most common grade 3-4 adverse events were immune-related, occurring in 101 (26%) patients in the ipilimumab group and 11 (3%) of patients in the placebo group. The most frequent grade 3-4 adverse events included diarrhoea (64 [16%] of 393 patients in the ipilimumab group vs seven [2%] of 396 in the placebo group), fatigue (40 [11%] vs 35 [9%]), anaemia (40 [10%] vs 43 [11%]), and colitis (18 [5%] vs 0). Four (1%) deaths occurred because of toxic effects of the study drug, all in the ipilimumab group.Interpretation Although there was no significant difference between the ipilimumab group and the placebo group in terms of overall survival in the primary analysis, there were signs of activity with the drug that warrant further investigation. Funding: Bristol-Myers Squibb. © 2014 Elsevier Ltd

Random expert sampling for deep learning segmentation of acute ischemic stroke on non-contrast CT.

Outlining acutely infarcted tissue on non-contrast CT is a challenging task for which human inter-reader agreement is limited. We explored two different methods for training a supervised deep learning algorithm: one that used a segmentation defined by majority vote among experts and another that trained randomly on separate individual expert segmentations. The data set consisted of 260 non-contrast CT studies in 233 patients with acute ischemic stroke recruited from the multicenter DEFUSE 3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3) trial. Additional external validation was performed using 33 patients with matched stroke onset times from the University Hospital Lausanne. A benchmark U-Net was trained on the reference annotations of three experienced neuroradiologists to segment ischemic brain tissue using majority vote and random expert sampling training schemes. The median of volume, overlap, and distance segmentation metrics were determined for agreement in lesion segmentations between (1) three experts, (2) the majority model and each expert, and (3) the random model and each expert. The two sided Wilcoxon signed rank test was used to compare performances (1) to 2) and (1) to (3). We further compared volumes with the 24 hour follow-up diffusion weighted imaging (DWI, final infarct core) and correlations with clinical outcome (modified Rankin Scale (mRS) at 90 days) with the Spearman method. The random model outperformed the inter-expert agreement ((1) to (2)) and the majority model ((1) to (3)) (dice 0.51±0.04 vs 0.36±0.05 (P<0.0001) vs 0.45±0.05 (P<0.0001)). The random model predicted volume correlated with clinical outcome (0.19, P<0.05), whereas the median expert volume and majority model volume did not. There was no significant difference when comparing the volume correlations between random model, median expert volume, and majority model to 24 hour follow-up DWI volume (P>0.05, n=51). The random model for ischemic injury delineation on non-contrast CT surpassed the inter-expert agreement ((1) to (2)) and the performance of the majority model ((1) to (3)). We showed that the random model volumetric measures of the model were consistent with 24 hour follow-up DWI