Simulation of Blood Flow and Nanoparticle Transport in a Stenosed Carotid Bifurcation and Pseudo-Arteriole

Numerical simulation of flow through a realistic bifurcated carotid artery geometry with a stenosis has been conducted for comparison to experimental measurements. The behaviour of simplified therapeutic nanoparticles in relatively low concentration was observed using a discrete particle approach. The role of size (diameters from 500 nm to 50 nm) in determining particle residence time and the potential for both desirable and undesirable wall interactions was investigated. It was found that mean particle residence time reduced with decreasing particle diameter, and the percentage of particles experiencing one or more wall interactions increased simultaneously. Further simulations were conducted on a scaled-down version of the geometry which approximated the size and flow conditions of an arteriole with capillary branches, and in this instance the mean residence time increased with decreasing particle diameter, owing largely to the greater influence of Brownian motion. 33% of all 50 nm particles were involved in wall interactions, indicating that smaller particles would have a greater ability to target, for instance, cancerous tumours in such regions

Durvalumab Plus Carboplatin/Paclitaxel Followed by Maintenance Durvalumab With or Without Olaparib as First-Line Treatment for Advanced Endometrial Cancer: The Phase III DUO-E Trial

PURPOSE Immunotherapy and chemotherapy combinations have shown activity in endometrial cancer, with greater benefit in mismatch repair (MMR)-deficient (dMMR) than MMR-proficient (pMMR) disease. Adding a poly(ADP-ribose) polymerase inhibitor may improve outcomes, especially in pMMR disease. METHODS This phase III, global, double-blind, placebo-controlled trial randomly assigned eligible patients with newly diagnosed advanced or recurrent endometrial cancer 1:1:1 to: carboplatin/paclitaxel plus durvalumab placebo followed by placebo maintenance (control arm); carboplatin/paclitaxel plus durvalumab followed by maintenance durvalumab plus olaparib placebo (durvalumab arm); or carboplatin/paclitaxel plus durvalumab followed by maintenance durvalumab plus olaparib (durvalumab + olaparib arm). The primary end points were progression-free survival (PFS) in the durvalumab arm versus control and the durvalumab + olaparib arm versus control. RESULTS Seven hundred eighteen patients were randomly assigned. In the intention-to-treat population, statistically significant PFS benefit was observed in the durvalumab (hazard ratio [HR], 0.71 [95% CI, 0.57 to 0.89]; P = .003) and durvalumab + olaparib arms (HR, 0.55 [95% CI, 0.43 to 0.69]; P < .0001) versus control. Prespecified, exploratory subgroup analyses showed PFS benefit in dMMR (HR [durvalumab v control], 0.42 [95% CI, 0.22 to 0.80]; HR [durvalumab + olaparib v control], 0.41 [95% CI, 0.21 to 0.75]) and pMMR subgroups (HR [durvalumab v control], 0.77 [95% CI, 0.60 to 0.97]; HR [durvalumab + olaparib v control] 0.57; [95% CI, 0.44 to 0.73]); and in PD-L1-positive subgroups (HR [durvalumab v control], 0.63 [95% CI, 0.48 to 0.83]; HR [durvalumab + olaparib v control], 0.42 [95% CI, 0.31 to 0.57]). Interim overall survival results (maturity approximately 28%) were supportive of the primary outcomes (durvalumab v control: HR, 0.77 [95% CI, 0.56 to 1.07]; P = .120; durvalumab + olaparib v control: HR, 0.59 [95% CI, 0.42 to 0.83]; P = .003). The safety profiles of the experimental arms were generally consistent with individual agents. CONCLUSION Carboplatin/paclitaxel plus durvalumab followed by maintenance durvalumab with or without olaparib demonstrated a statistically significant and clinically meaningful PFS benefit in patients with advanced or recurrent endometrial cancer

Can We Learn From Nature to Design Membranes? The Intricate Pore Structure of the Diatom

Membranes are ubiquitous functional elements used in separation processes. An ideal membrane will stop certain species penetrating it while having excellent transport properties for others. Membranes are used in synthetic systems such as fuel cells and desalination plants, but are also formed naturally in biological systems. For example all cells use a membrane to contain the cellular contents, while allowing transport of nutrients though the cell wall. I will present our recent work on examining diatoms, which are unicellular algae that grow in water. They have a self assembled silica membrane wall with a regular array of nanopores whose function is very poorly understood. I will outline the unique structure of the pores and our experimental work on understanding their structure to help develop membranes with better performance.</jats:p

Effect of Superhydrophobicity on Impinging Droplet Heat Transfer

In this study we present a preliminary investigation into the effect of hydrophobicity on the heat transfer rate due to the impingement of cold water droplets on heated flat surfaces. Two extreme contact angles were compared; hydrophilic (∼20°) and superhydrophobic (∼160°) using different surface coatings on a thin metal substrates. Images of the droplet impingement were simultaneously recorded by a high speed camera and a high speed, high resolution infrared camera so we could correlate droplet shape and dynamics to the heat transfer rate. There is a large effect on both the droplet fluid dynamics and heat transfer between hydrophilic and superhydrophobic surfaces. The heat transfer difference between the superhydrophobic and hydrophilic cases is a complex interplay between the increased droplet contact line velocity due to induced slip and the insulating properties of the air gap. Overall we have shown significant reductions in both the instantaneous heat transfer rates and the overall cooling effect of droplets impinging on superhydrophobic surfaces relative to those for hydrophilic surfaces. In the range of droplet velocities varied (We = 50 to 190) there was little dependency of the heat transfer or fluid flow with impact velocity, due to the dominance of inertial forces.</jats:p

Spectral light management for solar energy conversion systems

Due to the inherent broadband nature of the solar radiation, combined with the narrow spectral sensitivity range of direct solar to electricity devices, there is a massive opportunity to manipulate the solar spectrum to increase the functionality and efficiency of solar energy conversion devices. Spectral splitting or manipulation facilitates the efficient combination of both high-temperature solar thermal systems, which can absorb over the entire solar spectrum to create heat, and photovoltaic cells, which only convert a range of wavelengths to electricity. It has only recently been possible, with the development of nanofabrication techniques, to integrate micro- and nano-photonic structures as spectrum splitters/manipulators into solar energy conversion devices. In this paper, we summarize the recent developments in beam splitting techniques, and highlight some relevant applications including combined PV-thermal collectors and efficient algae production, and suggest paths for future development in this field

Spectrally Splitting Hybrid Photovoltaic/thermal Receiver Design for a Linear Concentrator

AbstractA new spectrally splitting photovoltaic-thermal hybrid receiver has been proposed and optimised for use in a linear concentrator with 10 to 20 suns concentration level. This hybrid system can produce high temperature thermal energy along with electrical output. Since photovoltaic cells cannot operate efficiently at high temperatures, they have been thermally decoupled from the thermal sub-module through spectral beam splitting, to avoid excessive heating of the cells. The proposed configuration incorporates a combination of dichroic filtering and selective volumetric absorption to divide the spectrum between the cells and the thermal sub-modules. The optics of the system has been studied using ray tracing and its performance has been compared against an ideal spectrally splitting system showing promising results

A Novel Hexagonal Beam Steering Electrowetting Device for Solar Energy Concentration

Traditional tracking devices for solar energy applications have several disadvantages, such as bulky mechanical structure, large wind loads, and ease of misalignment. This study aims to design a flat, thin, and adaptive beam steering device to eliminate these drawbacks. A proof of concept device was fabricated to demonstrate this design. The novelty of the proof of concept device is the hexagonal structure of the electrowetting cell design. The hexagonal cell was dosed with two immiscible liquids with different refractive indices. The hypothesis of this design is that by deforming the liquid shape with the application of voltage, light can be steered and concentrated for solar energy applications. A maximum contact angle change of 44&deg; was observed with the application of 26 V to one of the electrodes of the hexagonal cell. The device demonstrated a 4.5&deg; change of laser beam path with only a 0.2 refractive index difference of the liquids. The 3D simulation model developed in this study shows that a tilted and flat interface can be achieved using higher dielectric constant dielectric materials. The device can facilitate the planer steering and concentration of sunlight for rooftop applications without moving mechanical parts