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The exceptional viscosity-modifying and yield stress properties of Carbopol are crucial in various industrial applications, from pharmaceuticals and personal care products to textile and paper. However, Carbopol aqueous solutions, especially in dilute conditions, lack elongational properties, which are essential for numerous applications, such as adhesives and sealants. The combination of different polymers allows for tuning both shear and elongational properties of a solution. This optimization is key to improving product performance and stability, and meeting the specific requirements of a desired application. In this study, we enhance the elongational properties of low concentration Carbopol aqueous solutions by adding polyethylene oxide (PEO) and characterize the resulting solutions using the filament stretching technique in transparent cross-shaped microchannels, where both continuous and dispersed phases are involved. The elongational viscosity is estimated by analyzing the filament thinning of the dispersed phase over time. Our findings indicate that the thinning process becomes more pronounced the more the continuous phase viscosity matches that of the dispersed one. Moreover, adding PEO to a Carbopol solution significantly impacts its elongational behavior, even at low concentrations of both polymers, indicating a synergistic effect between the polymers in modulating the elongational properties. [ABSTRACT FROM AUTHOR]

Ovine pulmonary adenocarcinoma (OPA) is an infectious, neoplastic lung disease of sheep that causes significant animal welfare and economic issues throughout the world. Understanding OPA pathogenesis is key to developing tools to control its impact. Central to this need is the availability of model systems that can monitor and track events after Jaagsiekte sheep retrovirus (JSRV) infection. Here, we report the development of an experimentally induced OPA model intended for this purpose. Using three different viral dose groups (low, intermediate and high), localised OPA tumour development was induced by bronchoscopic JSRV instillation into the segmental bronchus of the right cardiac lung lobe. Pre-clinical OPA diagnosis and tumour progression were monitored by monthly computed tomography (CT) imaging and trans-thoracic ultrasound scanning. Post mortem examination and immunohistochemistry confirmed OPA development in 89% of the JSRV-instilled animals. All three viral doses produced a range of OPA lesion types, including microscopic disease and gross tumours; however, larger lesions were more frequently identified in the low and intermediate viral groups. Overall, 31% of JSRV-infected sheep developed localised advanced lesions. Of the sheep that developed localised advanced lesions, tumour volume doubling times (calculated using thoracic CT 3D reconstructions) were 14.8 ± 2.1 days. The ability of ultrasound to track tumour development was compared against CT; the results indicated a strong significant association between paired CT and ultrasound measurements at each time point (R2 = 0.799, p < 0.0001). We believe that the range of OPA lesion types induced by this model replicates aspects of naturally occurring disease and will improve OPA research by providing novel insights into JSRV infectivity and OPA disease progression. [ABSTRACT FROM AUTHOR]

Inertial effects on sheared emulsion droplets are a topic of scientific and industrial interest for several applications from processing to microfluidics. Most of the literature have addressed so far the role of inertia of the continuous phase, which is known to affect shear-induced droplet deformation and migration at values of the Reynolds number of the external fluid Rec > 1. However, less attention has been paid to the case of inertial effects inside the droplets, corresponding to values of the Reynolds number of the droplet fluid Red > 1. Such a case is especially relevant when the viscosity ratio λ between the droplet and the external fluid is ≪ 1, which is typical of water-in-oil emulsions where the low values of droplet viscosity can result in Red > 1, while Rec < 1 due to the larger oil viscosity. Here, we focus on the effect of droplet inertia under shear flow at λ ≪ 1 by high-speed video microscopy experiments in a microcapillary and by numerical simulations based on a front-tracking finite-difference method. The results unveil the droplet's three-dimensional shape under shear flow at low viscosity ratios and show that droplet inertia tends to increase droplet deformation and orientation along the flow direction and to form two vortices inside the droplets even at small Rec. The latter findings are at variance with the case of external fluid inertia, where droplets become more aligned with the velocity gradient direction. [ABSTRACT FROM AUTHOR]

CLN1 disease, also called infantile neuronal ceroid lipofuscinosis (NCL) or infantile Batten disease, is a fatal neurodegenerative lysosomal storage disorder resulting from mutations in the CLN1 gene encoding the soluble lysosomal enzyme palmitoylprotein thioesterase 1 (PPT1). Therapies for CLN1 disease have proven challenging because of the aggressive disease course and the need to treat widespread areas of the brain and spinal cord. Indeed, gene therapy has proven less effective for CLN1 disease than for other similar lysosomal enzyme deficiencies. We therefore tested the efficacy of enzyme replacement therapy (ERT) by administering monthly infusions of recombinant human PPT1 (rhPPT1) to PPT1-deficient mice ([Cln1.sup.-/-]) and CLN1rr15x sheep to assess how to potentially scale up for translation. In [Cln1.sup.-/-]mice, intracerebrovascular (i.c.v.) rhPPT1 delivery was the most effective route of administration, resulting in therapeutically relevant CNS levels of PPT1 activity. rhPPT1treated mice had improved motor function, reduced disease-associated pathology, and diminished neuronal loss. In [CLN1.sup.R151X] sheep, i.c.v. infusions resulted in widespread rhPPT1 distribution and positive treatment effects measured by quantitative structural MRI and neuropathology. This study demonstrates the feasibility and therapeutic efficacy of i.c.v. rhPPT1 ERT. These findings represent a key step toward clinical testing of ERT in children with CLN1 disease and highlight the importance of a cross-species approach to developing a successful treatment strategy., Introduction In contrast to other monogenic causes of neurodegeneration such as mitochondrial and peroxisomal disease (1, 2), the majority of fatal lysosomal storage disorders (LSDs) are caused by a deficiency [...]

The measurement of the stress state of rock, carried out insitu using the overcoring CSIRO HI Cell technique, provides valuable information about the rock mass geo-structural and stress conditions. This is particularly useful for calibrating the numerical model of natural slopes and excavations fronts and for assessing their static conditions. Thus, it allows to improve workplace safety conditions in both open-pit and underground quarries. During an in-situ CSIRO test, the stress release strains are measured by 12 strain gauges differently oriented in the space and the stress tensor and the material elastic parameters are then computed. The classic interpretative procedure of stress release test refers to analytical formulations that assume an extracted sample of regular cylindrical shape. However, during overcoring, it may happen that a discontinuity is intercepted, causing the extracted core to break and to assume an irregular shape. To address this challenge, in this work, a Finite Element numerical simulation of stress release was conducted basing on a 3D digital model of the irregular sample resulting from a Photogrammetric Survey. This allowed for the computation of the stress tensor for both irregularly shaped and ideal cylindrical samples. The research proceeded as it follows: i) three-dimensional modelling of the irregularly shaped core using Photogrammetric Techniques and Mesh Editing, which enabled the accurate representation of complex geometries; ii) numerical Modelling of the irregularly shaped core containing the CSIRO HI Cell through Finite Element Analysis, providing insights about stress and deformation distributions; iii) stress State of the rock calculation using a Multiple Linear Regression Procedure by using the coefficient matrix as determined by the core numerical modelling. The implementation of this procedure may facilitate the determination of stress state for irregularly shaped cores, and it enhances to understand how shape and rock elastic properties may influence the stress release behaviour. This comprehensive approach could allow to address challenges associated to stress assessment for irregular shaped rock cores and to improve the accuracy and applicability of geotechnical engineering methods. [ABSTRACT FROM AUTHOR]