Responses of Vascular Endothelial Cells to Photoembossed Topographies on Poly(Methyl Methacrylate) Films.

Failures of vascular grafts are normally caused by the lack of a durable and adherent endothelium covering the graft which leads to thrombus and neointima formation. A promising approach to overcome these issues is to create a functional, quiescent monolayer of endothelial cells on the surface of implants. The present study reports for the first time on the use of photoembossing as a technique to create polymer films with different topographical features for improved cell interaction in biomedical applications. For this, a photopolymer is created by mixing poly(methyl methacrylate) (PMMA) and trimethylolpropane ethoxylate triacrylate (TPETA) at a 1:1 ratio. This photopolymer demonstrated an improvement in biocompatibility over PMMA which is already known to be biocompatible and has been extensively used in the biomedical field. Additionally, photoembossed films showed significantly improved cell attachment and proliferation compared to their non-embossed counterparts. Surface texturing consisted of grooves of different pitches (6, 10, and 20 µm) and heights (1 µm and 2.5 µm). The 20 µm pitch photoembossed films significantly accelerated cell migration in a wound-healing assay, while films with a 6 µm pitch inhibited cells from detaching. Additionally, the relief structure obtained by photoembossing also changed the surface wettability of the substrates. Photoembossed PMMA-TPETA systems benefited from this change as it improved their water contact angle to around 70°, making it well suited for cell adhesion.This project was supported in part by MRC/EPSRC grant G0502256-77947. Lin Qiu was supported by a joint PhD studentship from Queen Mary University of London and the China Scholarship Council (CSC) between 2010 and 2014

Smart Specification Setting for Dry Powder Inhalation Carriers

The specifications of excipients are important to pharmaceutical manufacturers to ensure that the final product can be manufactured robustly over the entire lifecycle of a drug product. Particle size specifications are key for dry powder inhalation excipients and they should be agreed between users and suppliers. The current paper evaluates two development strategies to set particle size specifications. It is shown that the application of quality-by-design principles to specification setting could result in broader specifications, while it guarantees that efficacy, safety and manufacturing of the medication is not affected. A multitude of reasons exist to keep specifications broader than the production capability range, including improved risk-mitigation and potentially reduced regulatory challenges during and after registration

Smart Specification Setting for Dry Powder Inhalation Carriers

The specifications of excipients are important to pharmaceutical manufacturers to ensure that the final product can be manufactured robustly over the entire lifecycle of a drug product. Particle size specifications are key for dry powder inhalation excipients and they should be agreed between users and suppliers. The current paper evaluates two development strategies to set particle size specifications. It is shown that the application of quality-by-design principles to specification setting could result in broader specifications, while it guarantees that efficacy, safety and manufacturing of the medication is not affected. A multitude of reasons exist to keep specifications broader than the production capability range, including improved risk-mitigation and potentially reduced regulatory challenges during and after registration

Correlated percolation and the correlated resistor network

We present some exact results on percolation properties of the Ising model, when the range of the percolating bonds is larger than nearest-neighbors. We show that for a percolation range to next-nearest neighbors the percolation threshold Tp is still equal to the Ising critical temperature Tc, and present the phase diagram for this type of percolation. In addition, we present Monte Carlo calculations of the finite size behavior of the correlated resistor network defined on the Ising model. The thermal exponent t of the conductivity that follows from it is found to be t = 0.2000 +- 0.0007. We observe no corrections to scaling in its finite size behavior.Comment: 16 pages, REVTeX, 6 figures include

Gender differences in the mitigating effect of co-parenting on parental burnout:The gender dimension applied to COVID-19 restrictions and parental burnout levels

Parenting is recognized as a complex and stressful activity, which in recent years has been linked to the potential development of parental burnout among mothers and fathers. With the spread of COVID-19 around the globe, not only have situations of health emergency and economic difficulty emerged, but also tremendous impacts on individual lives and family role divisions, which continue to be experienced today. As lockdown measures have affected unemployment rates, financial insecurity levels, social support, amount of leisure time, and the number of caring responsibilities, parents are expected to be at higher risk for developing parental burnout. Co-parenting is presented as a factor which can mitigate the effect between COVID-19 lockdown measures and the levels of experienced parental burnout. Nevertheless, we argue that the role of co-parenting in association with the implications of COVID-19 on parental stress differs between men and women. As parenthood remains an activity that is largely gender-based, co-parenting is hypothesized to be of more crucial importance in attenuating the effect between COVID-19 lockdown measures and parental burnout for fathers in comparison to mothers. Our results confirm previous findings that COVID-19 has increased levels of parental burnout. The relationship between state-imposed COVID-19 lockdown measures and levels of parental burnout was not found to be significantly affected by co-parenting. However, when assessing this two-way interaction separately for men and women, we saw that this mitigating effect was significant for fathers and non-significant for mothers

Artificial intelligence for automated Carnegie staging of the human embryo in three-dimensional ultrasound:the Rotterdam periconception cohort

Since automatic Carnegie staging using AI is real-time and does not require a VR set-up adoption in clinical practice becomes feasible. In future work, we aim to enhance interpretability by analysing the specific morphological aspects in ultrasound scans utilised by the algorithm to assign the Carnegie stage. Understanding the morphological aspects linked to the Carnegie stage by the algorithm might lead to more in-depth insight into the patterns of normal and abnormal morphological development across pregnancie

Increased efficiency of luminescent solar concentrators after application of organic wavelength selective mirrors

Organic wavelength-selective mirrors are used to reduce the loss of emitted photons through the surface of a luminescent solar concentrator (LSC). A theoretical calculation suggests that application of a 400 nm broad reflector on top of an LSC containing BASF Lumogen Red 305 as a luminophore can reflect 91% of all surface emitted photons back into the device. Used in this way, such broad reflectors could increase the edge-emission efficiency of the LSC by up to 66%. Similarly, 175 nm broad reflectors could increase efficiency up to 45%. Measurements demonstrate more limited effectiveness and dependency on the peak absorbance of the LSC. At higher absorbance, the increased number of internal re-absorption events reduces the effectiveness of the reflectors, leading to a maximum increase in LSC efficiency of ~5% for an LSC with a peak absorbance of 1. Reducing re-absorption by reducing dye concentration or the coverage of the luminophore coating results in an increase in LSC efficiency of up to 30% and 27%, respectively

Viscoelastic liquid crystal colloids for the continuous processing of twisted nematic electro-optical cells

Liquid crystal colloid materials are described based on the liquid crystal (LC) E7 and submicron sized poly(methyl methacrylate-co-divinylbenzene) particles. Application of a thermal treatment to the composite material produces a finely dispersed network of the internally crosslinked polymeric inclusions in the LC-E7. Dynamic rheological measurements on the LC colloids show that the presence of this network imposes pronounced viscoelastic behavior on the material, which may be exploited in the manufacturing of large-area twisted nematic (TN) electro-optical cells via continuous methods as an alternative to the currently available batchwise routes. The electro-optical characteristics of TN cells based on the composite material are approximately comparable to the electro-optical characteristics of a reference cell filled with pure LC E7, which ensures that the largely increased viscoelasticity of the composite does not lead to a degradation of electro-optical propertie

Glass-like transparent high strength polyethylene films by tuning drawing temperature

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service toour customers we are providing this early version of the manuscript. The manuscript will undergocopyediting, typesetting, and review of the resulting proof before it is published in its final formY. Lin greatly acknowledges financial support by the China Scholarship Council (CSC)