Nottingham Trent University

About: Nottingham Trent University is a education organization based out in Nottingham, United Kingdom. It is known for research contribution in the topics: Population & Addiction. The organization has 4702 authors who have published 12862 publications receiving 307430 citations. The organization is also known as: NTU & Trent Polytechnic.

Wetting considerations in capillary rise and imbibition in closed square tubes and open rectangular cross-section channels

Abstract: The spontaneous capillary-driven filling of microchannels is important for a wide range of applications. These channels are often rectangular in cross-section, can be closed or open, and horizontal or vertically orientated. In this work, we develop the theory for capillary imbibition and rise in channels of rectangular cross-section, taking into account rigidified and non-rigidified boundary conditions for the liquid–air interfaces and the effects of surface topography assuming Wenzel or Cassie-Baxter states. We provide simple interpolation formulae for the viscous friction associated with flow through rectangular cross-section channels as a function of aspect ratio. We derive a dimensionless cross-over time, T c, below which the exact numerical solution can be approximated by the Bousanquet solution and above which by the visco-gravitational solution. For capillary rise heights significantly below the equilibrium height, this cross-over time is T c ≈ (3X e/2)2/3 and has an associated dimensionless cross-over rise height X c ≈ (3X e/2)1/3, where X e = 1/G is the dimensionless equilibrium rise height and G is a dimensionless form of the acceleration due to gravity. We also show from wetting considerations that for rectangular channels, fingers of a wetting liquid can be expected to imbibe in advance of the main meniscus along the corners of the channel walls. We test the theory via capillary rise experiments using polydimethylsiloxane oils of viscosity 96.0, 48.0, 19.2 and 4.8 mPa s within a range of closed square tubes and open rectangular cross-section channels with SU-8 walls. We show that the capillary rise heights can be fitted using the exact numerical solution and that these are similar to fits using the analytical visco-gravitational solution. The viscous friction contribution was found to be slightly higher than predicted by theory assuming a non-rigidified liquid–air boundary, but far below that for a rigidified boundary, which was recently reported for imbibition into horizontally mounted open microchannels. In these experiments we also observed fingers of liquid spreading along the internal edges of the channels in advance of the main body of liquid consistent with wetting expectations. We briefly discuss the implications of these observations for the design of microfluidic systems.

Arthrogenic muscle inhibition after ACL reconstruction: a scoping review of the efficacy of interventions

Abstract: Objective To determine whether reported therapeutic interventions for arthrogenic muscle inhibition (AMI) in patients with ACL injuries, following ACL reconstruction, or in laboratory studies of AMI, are effective in improving quadriceps activation failure when compared with standard therapy in control groups Design A scoping review of the efficacy of interventions was conducted in accordance with the methodological framework of Arksey and O’Malley and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines Search terms included ‘arthrogenic muscle inhibition’, ‘quadriceps activation following knee injuries’, ‘anterior cruciate’ or ‘knee’ combined with ‘quadriceps activation’, ‘quadriceps inhibition’, ‘corticomotor’, ‘arthrogenic’, ‘brain activation’ and ‘neuroplasticity’ Articles were evaluated for risk of bias using the PEDro (Physiotherapy Evidence Database) criteria The overall quality of evidence for each intervention was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) Data sources PubMed, EMBASE and Cumulative Index to Nursing and Allied Health Literature databases Eligibility criteria for selecting studies Isolated case reports and articles reporting outcomes in patients with chronic disease or major trauma were excluded All other original research articles were included Results 780 potential articles were identified 20 met the inclusion criteria These studies provided a moderate quality of evidence to support the efficacy of cryotherapy and physical exercises in the management of AMI There was low-quality evidence for efficacy of neuromuscular electrical stimulation and transcutaneous electrical nerve stimulation, and very low-quality evidence for efficacy of ultrasound and vibration Conclusions This scoping review demonstrated moderate-quality evidence for the efficacy of cryotherapy and physical exercises in improving quadriceps activation failure after ACL injury and reconstruction These therapeutic modalities are therefore recommended in the management of AMI