Preoperative ketamine administration for prevention of postoperative neurocognitive disorders after major orthopedic surgery in elderly patients: A multicenter randomized blinded placebo-controlled trial.

Background: Preventive anesthetic impact on the high rates of postoperative neurocognitive disorders in elderly patients is debated. The Prevention of postOperative Cognitive dysfunction by Ketamine (POCK) study aimed to assess the effect of ketamine on this condition.

Methods: This is a multicenter, randomized, double-blind, interventional study.

The air conditioning in the nose of mammals depends on their mass and on their maximal running speed.

The nose of the mammals is responsible for filtering, humidifying, and heating the air before entering the lower respiratory tract. This conditioning avoids, notably, dehydration of the bronchial and alveolar mucosa. However, since this conditioning is not perfect, exercising in cold air can induce lung inflammation, both for human and non-human mammals.

What Are the Key Anatomical Features for the Success of Nose-to-Brain Delivery? A Study of Powder Deposition in 3D-Printed Nasal Casts.

Nose-to-brain delivery is a promising way to improve the treatment of central nervous system disorders, as it allows the bypassing of the blood-brain barrier. However, it is still largely unknown how the anatomy of the nose can influence the treatment outcome. In this work, we used 3D printing to produce nasal replicas based on 11 different CT scans presenting various anatomical features.

Instrumented Flexible Glass Structure: A Bragg Grating Inscribed with Femtosecond Laser Used as a Bending Sensor.

Fused silica glass is a material with outstanding mechanical, thermal and optical properties. Being a brittle material, it is challenging to shape. In the last decade, the manufacturing of monolithic flexible mechanisms in fused silica has evolved with the femtosecond-laser-assisted etching process.

Femtosecond pulse laser-engineered glass flexible structures instrumented with an in-built Bragg grating sensor.

The advent of near-infrared femtosecond pulse laser has enabled the highly-resolved manufacturing of micro/nano structures in various materials including glass. In this paper, we make use of an automated femtosecond laser system, so-called Femtoprint, to design a monolithic self-instrumented mechanism that we use for in-built strain sensing. To that aim, a flexible structure is designed and produced from a silica planar substrate.

Strategies to Assess Occupational Exposure to Airborne Nanoparticles: Systematic Review and Recommendations.

In many industrial sectors, workers are exposed to manufactured or unintentionally emitted airborne nanoparticles (NPs). To develop prevention and enhance knowledge surrounding exposure, it has become crucial to achieve a consensus on how to assess exposure to airborne NPs by inhalation in the workplace. Here, we review the literature presenting recommendations on assessing occupational exposure to NPs.

In vitro Evaluation of Paliperidone Palmitate Loaded Cubosomes Effective for Nasal-to-Brain Delivery.

Introduction: This work aimed to develop chitosan-coated cubosomal nanoparticles intended for nose-to-brain delivery of paliperidone palmitate. They were compared with standard and cationic cubosomal nanoparticles. This comparison relies on numerous classical in vitro tests and powder deposition within a 3D-printed nasal cast.

Controlled transitions between metastable states of 2D magnetocapillary crystals.

Magnetocapillary interactions between particles allow to self-assemble floating crystals along liquid interfaces. For a fixed number of particles, different states possessing different symmetrical features, known as metastable states, coexist. In this paper, we demonstrate how to trigger the transition from one state to another, either by rearranging the crystal, or by controlling its growth.

Validation and Sensitivity analysis for a nasal spray deposition computational model.

Validating numerical models against experimental models of nasal spray deposition is challenging since many aspects must be considered. That being said, it is a critical step in the product development process of nasal spray devices. This work presents the validation process of a nasal deposition model, which demonstrates a high degree of consistency of the numerical model with experimental data when the nasal cavity is segmented into two regions but not into three.

A Volume-Tuning Capillary Gripper That Enhances Handling Capabilities and Enables Testing of Micro-Components.

Capillary forces are shown to be extremely effective for micro-assembly and pick-and-place processes, especially for their ability to self-align the handled objects. However, in today's machines, micro-objects are submitted to high loads, such as compressions for the electrical testing of the micro-components, or inertial forces coming from the high accelerations of the machines. There, capillary grippers may show some limits.

Instillation of a Dry Powder in Nasal Casts: Parameters Influencing the Olfactory Deposition With Uni- and Bi-Directional Devices.

Nose-to-brain delivery is a promising way to reach the central nervous system with therapeutic drugs. However, the location of the olfactory region at the top of the nasal cavity complexifies this route of administration. In this study, we used a 3D-printed replica of a nasal cavity (a so-called "nasal cast") to reproduce the deposition of a solid powder.

A Soft Pneumatic Two-Degree-of-Freedom Actuator for Endoscopy.

The rise of soft robotics opens new opportunities in endoscopy and minimally invasive surgery. Pneumatic catheters offer a promising alternative to conventional steerable catheters for safe navigation through the natural pathways without tissue injury. In this work, we present an optimized 6 mm diameter two-degree-of-freedom pneumatic actuator, able to bend in every direction and incorporating a 1 mm working channel.

Optimization and assessment of a novel gastric electrode anchoring system designed to be implanted by minimally invasive surgery.

A novel electrode anchoring design and its implantation procedure, aiming for a minimally invasive solution for gastric electrical stimulation, are presented. The system comprises an anchor made of a flexible body embedding two needle-shaped electrodes. The electrodes can easily switch from a parallel position - to pierce the stomach - to a diverging position - enabling them to remain firmly anchored into the muscular layer of the stomach.

The importance of pre-formulation studies and of 3D-printed nasal casts in the success of a pharmaceutical product intended for nose-to-brain delivery.

This review aims to cement three hot topics in drug delivery: (a) the pre-formulation of new products intended for nose-to-brain delivery; (b) the development of nasal casts for studying the efficacy of potential new nose-to-brain delivery systems at the early of their development (pre-formulation); (c) the use of 3D printing based on a wide variety of materials (transparent, biocompatible, flexible) providing an unprecedented fabrication tool towards personalized medicine by printing nasal cast on-demand based on CT scans of patients. This review intends to show the links between these three subjects. Indeed, the pathway selected to administrate the drug to the brain not only influence the formulation strategies to implement but also the design of the cast, to get the most convincing measures from it.

Optimization of Phase-Change Material-Elastomer Composite and Integration in Kirigami-Inspired Voxel-Based Actuators.

Phase-change material-elastomer composite (PCMEC) actuators are composed of a soft elastomer matrix embedding a phase-change fluid, typically ethanol, in microbubbles. When increasing the temperature, the phase change in each bubble induces a macroscopic expansion of the matrix. This class of actuators is promising for soft robotic applications because of their high energy density and actuation strain, and their low cost and easy manufacturing.

A consensus research agenda for optimising nasal drug delivery.

Nasal drug delivery has specific challenges which are distinct from oral inhalation, alongside which it is often considered. The next generation of nasal products will be required to deliver new classes of molecule, e.g.

Pick up and release of micro-objects: a motion-free method to change the conformity of a capillary contact.

We propose a new 3D-printed capillary gripper equipped with a textured surface for motion-free release. The gripper classically picks up micro-objects thanks to the capillary forces induced by a liquid bridge. Micro-objects are released by decreasing the volume of this bridge through evaporation.

Design, characterization and optimization of a soft fluidic actuator for minimally invasive surgery.

Purpose: In minimally invasive surgery and endoscopy, the rise of soft robotics, using materials of similar softness as biological soft tissues, opens many new opportunities. Soft actuated catheters could become an alternative to current steerable catheters, by minimizing the risk of damage to surrounding tissues while enhancing the possibilities to navigate in confined space and to reach remote locations. Fluidic actuators present the advantage to be safe, since they do not require rigid parts nor voltage, to be lightweight, and to allow the reduction of the number of parts needed for a given movement.

Rupture of a Liquid Bridge between a Cone and a Plane.

In this work, a systematic experimental study of the rupture of an axially symmetric liquid bridge between a cone and a plane was performed, with focus on the volume distribution after break up. A model based on the Young-Laplace equation is presented, and its solutions are compared to experimental data. Cones and conical cavities with different aperture angles were used in our experiments.

Microscale Surface Tension and its Applications.

More than 200 years since the earliest scientific investigations by Young, Laplace and Plateau, liquid surface tension is still the object of thriving fundamental and applied research [...

Adhesive elastocapillary force on a cantilever beam.

This paper reports an experimental and theoretical investigation of a cantilever beam in contact with an underlying substrate, in the presence of an intervening liquid bridge. The beam is deflected in response to the adhesive capillary forces generated by the liquid. Three main regimes of contact are observed, similarly to other elastocapillary systems already reported in the literature.

Hybrid Two-Scale Fabrication of Sub-Millimetric Capillary Grippers.

Capillary gripping is a pick-and-place technique that is particularly well-suited for handling sub-millimetric components. Nevertheless, integrating a fluid supply and release mechanism becomes increasingly difficult to manufacture for these scales. In the present contribution, two hybrid manufacturing procedures are introduced in which the creation of the smallest features is decoupled from the macro-scale components.

In situ cancer diagnosis through online plasmonics.

Most cancer diagnoses rely on biomarkers detection. This could be improved if directly conducted in suspicious cancer spots, preventing the need for biopsy. Lung cancer remains a perfect study-case for such a development, as it is generally detected at advanced stage and is in the need for early diagnosis techniques.

Liquid secretion and setal compliance: the beetle's winning combination for a robust and reversible adhesion.

This paper is a brief review and discussion of the recent literature on the hairy adhesive pads of beetles, with the focus on two features of these pads, firstly, compliant setal tips and secondly, a liquid secretion, that together guarantee robust cycles of attachment/detachment on smooth and rough substrates. The compliance is required to ensure sufficient contact between the setal tips and the substrate with a minimum of elastically stored energy at the contact interface. The secretion fills potential gaps between both surfaces, generates capillary adhesive forces, and enhances self-cleaning of these microstructures.

Fast IR-Actuated Shape-Memory Polymers Using in Situ Silver Nanoparticle-Grafted Cellulose Nanocrystals.

In recent years, shape-memory polymers (SMPs) have gained a key position in the realm of actuating applications from daily life products to biomedical and aeronautic devices. Most of these SMPs rely mainly on shape changes upon direct heat exposure or after stimulus conversion (e.g.