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This paper aims to develop a novel micro-ablation system to realise micrometric and well-defined hydrogel structures. To engineer a tissue it is necessary to evaluate several aspects, such as cell-cell and cell-substrate interactions, its micro-architecture and mechanical stimuli that act on it. For this reason, it is important to fabricate a substrate which presents a microtopology similar to natural tissue and has chemical and mechanical properties able to promote cell functions. In this paper, well-defined hydrogel structures embedding cells were microfabricated using a purposely developed technique, micro-laser ablation, based on a thulium laser. Its working parameters (laser power emission, stepper motor velocity) were optimised to produce shaded “serpentine” pattern on a hydrogel film.

In this study, initially, swelling/contraction tests on agarose and alginate hydrogel in different solutions of main components of cell culture medium were performed and were compared with the MECpH model. This comparison matched with good approximation experimental measurements. Once known how hydrogel changed its topology, microstructures with a well-defined topology were realised using a purposely developed micro-laser ablation system design. S5Y5 neuroblastoma cell lines were embedded in hydrogel matrix and the whole structure was ablated with a laser microfabrication system. The cells did not show damages due to mechanical stress present in the hydrogel matrix and to thermal increase induced by the laser beam.

The hydrogel structure is able to reproduce extracellular matrix. Initially, the hydrogel swelling/contraction in different solutions, containing the main components of the most common cell culture media, was analysed. This analysis is important to evaluate if cell culture environment could alter microtopology of realised structures. Then, the same topology was realised on hydrogel film embedding neuronal cells and the cells did not show damages due to mechanical stress present in the hydrogel matrix and to thermal increase induced by the laser beam. The interesting obtained results could be useful to realise well-defined microfabricated hydrogel structures embedding cells to guide tissue formation

The originality of this paper is the design and realisation of a 3D microfabrication system able to microfabricate hydrogel matrix embedding cells without inducing cell damage. The ease of use of this system and its potential modularity render this system a novel potential device for application in tissue engineering and regenerative medicine area.

The traditional tissue engineering approach employs rapid prototyping systems to realise microstructures (i.e. scaffolds) which recapitulate the function and organization of native tissues. The purpose of this paper is to describe a new rapid prototyping system (PAM‐modular micro‐fabrication system, PAM²) able to fabricate microstructures using materials with different properties in a controlled environment.

Computer‐aided technologies were used to design multi‐scale biological models. Scaffolds with specific features were then designed using custom software and manufactured using suitable modules. In particular, several manufacturing modules were realised to enlarge the PAM² processing material window, controlling physical parameters such as pressure, force, temperature and light. These modules were integrated in PAM², allowing a precise control of fabrication parameters through a modular approach and hardware configuration.

Synthetic and natural polymeric solutions, thermo‐sensitive and photo‐sensitive materials can be used to fabricate 3D scaffolds. Both simple and complex architectures with high fidelity and spatial resolution ranging from ±15 μm to ±200μm (according to ink properties and extrusion module used) were realised.

The PAM² system is a new rapid prototyping technique which operates in controlled conditions (for example temperature, pressure or light intensity) and integrates several manufacturing modules for the fabrication of complex or multimaterial microstructures. In this paper it is shown how the system can be configured and then used to fabricate scaffolds mimicking the extra‐cellular matrix, both in its properties (i.e. physic‐chemical and mechanical properties) and architecture.

The application of laser and optical technologies in the industry is wide and extensive; the development and application of laser and optical technologies have become a promising research domain. However, most existing studies have focused on the technical aspects or the application aspects; these studies have not highlighted the technology distribution and application development of laser and optical technologies from the big picture. Additionally, the manner in which the research and development (R&D) results of universities correspond to the needs of enterprises and industry has become a topic of concern for the public. Therefore, this study aims to adopt the academic patents as the basis for analysis and to construct a laser and optical technology network.

Therefore, in the current study, the researchers have analyzed relevant academic patent technology networks, using academic patents of laser and optical technologies as a basis of analysis.

The study results indicated that the key technologies mainly lie in nanostructures, metal-working, material analysis and semiconductor devices. Additionally, these technologies are mainly applied in industries, such as optics, medical technology, pharmaceuticals, biotechnology and organic fine chemistry; this indicated that a large proportion of academia’s R&D outcomes are applied in these industries.

In this study, the researchers have constructed a technology network model to explore the technical development direction of laser and optical technologies; the results of the current study could serve as a reference for universities and industry for allocation of R&D resources.

Trans-oral robotic surgery (TORS) is increasingly employed in obstructive sleep apnoea (OSA) management. Objective outcomes are generally assessed through polysomnography. Pre-operative magnetic resonance imaging (MRI) can be a useful adjunct in objective upper airway assessment, in particular the tongue base, providing useful information for surgical planning and outcome assessment, though care must be taken in patient positioning during surgery. The purpose of this paper is to identify pitfalls in this process and suggest a protocol for pre-operative MRI scanning in OSA.

This study is a four-patient prospective case-series and literature review. Outcome measures include pre- and post-operative volumetric changes in the pharynx as measured on MRI and apnoea–hypopnea indices (AHI), with cure being OSA resolution or a 50 per cent reduction in AHI.

All patients achieved AHI reduction and/or OSA cure following TORS, despite a decrease in pharyngeal volume measurements at the tongue base level. This study and others lacked standardisation in the MRI scanning protocol, which resulted in an inability to effectively compare pre- and post-operative scans. Pitfalls were related to variation in head/tongue position, soft-tissue marker usage and assessed area boundary limits.

TORS appears to be effective in OSA management. A new protocol for patient positioning and anatomical landmarks is suggested.

The findings could provide directly comparable data between scans and may allow correlation between tongue base volumetric changes and AHI through subsequent and historical study meta-analysis.

There are various temperature measuring systems presented in the literature and on the market today. Over the past number of years a range of luminescent‐based optical fibre sensors have been reported and developed which include fluorescence and optical scattering. These temperature sensors incorporate materials that emit wavelength shifted light when excited by an optical source. The majority of commercially available systems are based on fluorescent properties.Design/methodology/approach – Many published journal articles and conference papers were investigated and existing temperature sensors in the market were examined.Findings – In optical thermometry, the light is used to carry temperature information. In many cases optical fibres are used to transmit and receive this light. Optical fibres are immune to electromagnetic interference and are small in size, which allows them to make very localized measurements. A temperature sensitive material forms a sensor and the subsequent optical data are transmitted via optical fibres to electronic detection systems. Two keys areas were investigated namely fluorescence based temperature sensors and temperature sensors involving optical scattering.Originality/value – An overview of optical fibre temperature sensors based on luminescence is presented. This review provides a summary of optical temperature sensors, old and new which exist in today's world of sensing.

The purpose of this paper is to provide an update to the Supply Chain Volatility Index (SCVI), and expand on prior work by presenting a conceptual framework illustrating how firms can deal with persistent volatility, the ensuing risk and mitigate the cost implications for their supply chain operations.

The authors use long-term time series of secondary data to assemble a “basket” of key indicators that are relevant to the business context within which global supply chains operate. The authors also report on five years of feedback gained from presentations of the SCVI to scholars and practitioners.

Volatility has reduced from record levels experienced during the global financial crises, yet remains at levels considerably higher than prior to the crisis, with no sign of a return to the more stable conditions that prevailed when many current supply chain networks were designed.

The authors reaffirm that new mental models are needed which embrace volatility as a factor in supply chain design, rather than seek to eradicate it in supply chain operations. Traditional static “network optimisation” based on a simple definition of low unit cost seems no longer appropriate under conditions of persistent volatility.

The authors provide a conceptual link of volatility, risk and cost in the supply chain, and outline how firms can develop a supply chain strategy by managing their exposure to volatility.

The authors challenge the common assumption that volatility invariably leads to risk and higher cost in the supply chain. Instead the authors argue that the supply chain structure can mitigate the exposure to supply chain risk. The authors introduce the concepts of recovery and resilience cost within a framework designed to help firms manage volatility-induced risk by minimising the adverse cost implications of volatility in their supply chains.

Considers the role of a range of materials being used in advanced sensor technology, including diamond, fullerenes, silicon carbide, superconductors, rare earths and III‐V compounds. Sensors based on these materials are described and their applications discussed.

The purpose of this paper is to explore, for the first time, the relationship between the prices of rare earth materials and economic growth. Renewable technologies and many high-demanded technologies need significant supplies of such materials.

The paper uses a panel of the six most significant rare earth producers around the globe, as well as certain panel methodologies.

The empirical analysis indicates the presence of a positive impact of such minerals prices on economic growth. Causality methodologies also indicate unidirectional causality between GDP and the prices of rare earth materials, with the causality running from these prices to economic growth. The findings survive a number of robustness checks.

The claim that natural resources are a curse that makes the countries worse off is not supported for the case of rare earth materials. The results are expected to be of high importance, because these particular rare earth materials are extensively used in a huge list of technological products with high demand and low costs, while they are hard to be replaced.

The purpose of this paper is to consider a detailed investigation of transversal magnetic (TM) nonlinear magnetooptical integrated optical sensor. The sensitivities of two sensors are presented. The first sensor composed of a dielectric thin film surrounded by a lossless, nonmagnetic, isotropic cladding exhibiting a local Kerr‐like dielectric nonlinearity, and a magnetic substrate chosen to be an iron garnet. The second sensor is formed by exchanging the cladding and the substrate media of the first sensor. The homogenous sensitivities of both sensors are calculated as a function of the waveguide thickness and the effective refractive index. The effect of nonlinearity on the sensitivities for both sensors is investigated.

The homogenous sensitivities of both sensors are calculated as a function of the waveguide thickness and the effective refractive index. The effect of nonlinearity on the sensitivities for both sensors is investigated. Numerical calculations are performed using the Maple program.

It was found that the sensitivity for the first sensor sensitivity increases with nonlinearity. While the sensitivity for the second sensor is hardly affected by the change of nonlinearity. It was also found that the thickness of the guiding layer is a critical parameter for the sensitivity of the optical sensor with the optimum thickness being just above cut‐off in case of the first structure and at the cut‐off in the case of the second structure.

A detailed investigation of TM nonlinear magnetooptical integrated optical sensor is considered. The two proposed structures are used to investigate the parameters to get the optimal sensitivity, which is an important issue is the sensor design.