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Electron beam is a way of radiation that can induce different reactions on polymers. The purpose of this work is to analyze the effect that the electron beam can produce on polyester fabrics.

Poly(ethylene terephthalate) (PET) fibres were treated at 0, 50, 100, 150, and 200 KGy. Later on surface modification was analyzed by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). Colorimetric and thermal measurements were studied too, as well as traction resistance.

Traction resistance showed no significant variations. As a result the authors could observe some changes in fabric witnesses and cristallinity increase, but no changes in traction resistance were observed. Moreover, when surface was studied, roughness was increased as oligomers moved towards fibre surface because of radiation dose.

The authors could appreciate roughness increased with radiation dose as well as yellowness and crystallinity.

This paper aims to discuss the effectiveness of the European Union (EU) at World Radiocommunication Conferences (WRCs) by comparing EU objectives prior to and outcomes of recent WRCs.

A thematic analysis of qualitative data extracted from documents is conducted. The effectiveness of the EU is discussed by using the concepts of agenda-setting and coalition-building, borrowed from international relations literature.

A clear conclusion on EU effectiveness could not be drawn based on the degree of match between EU objectives and WRC outcomes. Other factors need to be included in the analysis, such as relevance of the EU’s participation at WRCs to the EU member states and availability and allocation of EU resources to the various stages of the WRC process.

Further research is encouraged to investigate the role of the EU at WRCs. In particular, interviews with experts involved in the WRC process may help gather relevant information on EU relevance and EU resource availability and allocation.

This paper contributes to existing research on international radio spectrum regulation by drawing attention to the role of the EU as an international actor.

This paper describes the use of the incremental flow formulation for the numerical analysis of forming processes. This formulation is based on the approximation of the flow type of constitutive equations by means of an algorithmic equation based on geometry changes over a timestep. The resulting equilibrium equations are functions of nodal positions. Hence geometrical constraints such as contact and incompressibility can be enforced in an exact manner. Two types of incremental equations leading to first and second order time approximations are presented. The more accurate case is based on the incremental logarithmic stretches. Several examples will be used to demonstrate the validity of the method.

The authors provide a comprehensive review of existing turnover studies in Spain. The literature review reveals that research on voluntary turnover is scarce, while other types of mobility, such as involuntary separations, downsizing, and planned turnover through contract date expiration, have received substantial attention. The authors identify the main institutional characteristics of Spain and explain why these may contribute to the low incidence of voluntary turnover. Specifically, the authors note that employment protection legislation, high unemployment, high unemployment insurance, centralized collective bargaining, the composition of the sector, high power distance, and in-group collectivism are important drivers of the patterns observed in existing turnover studies. The authors also explore how some of the mechanisms and processes exposed by key turnover theories may be applicable to the Spanish context. This chapter highlights the importance of paying attention to the role of the institutional and cultural context to understand different mobility patterns in the labor market. The authors also suggest several avenues for future research including the study of different turnover types, employer and employee outcomes, cultural variations, and employment practices.

To maximise acoustic comfort in a classroom, the acoustic conditions of the space should be variable. So, the optimal acoustic state also changes when the classroom changes from a study environment into a lecture environment. Passive Variable Acoustic Technology (PVAT) alters a room’s Reverberation Time (RT) by changing the total sound absorption in a room. The purpose of this paper is to evaluate the improvements to classroom acoustic comfort when using PVAT.

The study is conducted in an existing tertiary classroom at Auckland University of Technology, New Zealand. The PVAT is prototyped, and the RTs are measured according to international standards before and after classroom installation. The acoustic measurement method used is a cost-effective application tool where pre- and post-conditions are of primary concern.

PVAT is found to offer statistically significant improvements in RT, but the key benefits are realised in its’ ability to vary RT for different classroom situations. It is predicted that the RT recommendations for two room types outlined in the acoustic standard AS/NZS 2107:2016 are satisfied when using PVAT in a single classroom space. By optimising RT, the acoustic comfort during both study and lecture is significantly improved.

When PVAT is combined with an intelligent system – Intelligent Passive Room Acoustic Technology (IPRAT) – it can detect sound waves in real time to identify the optimal RT. This paper details a pilot case study that works towards quantifying the benefits of IPRAT, by prototyping and testing the PVAT component of the system.

1. A pilot case study outlines the development and test of a variable acoustic prototype in a tertiary classroom

2. A method is adopted to measure acoustic conditions, using three under-researched Android applications

3. The benefits of PVAT are realised in its ability to vary RT by adjusting the prototypes’ sound absorption

4. By using PVAT in a single space, the recommended RTs for two room types outlined in the acoustic standard AS/NZS 2107:2016 can be satisfied

5. The improvements in acoustic comfort due to PVAT are statistically significant

A pilot case study outlines the development and test of a variable acoustic prototype in a tertiary classroom

A method is adopted to measure acoustic conditions, using three under-researched Android applications

The benefits of PVAT are realised in its ability to vary RT by adjusting the prototypes’ sound absorption

By using PVAT in a single space, the recommended RTs for two room types outlined in the acoustic standard AS/NZS 2107:2016 can be satisfied

The improvements in acoustic comfort due to PVAT are statistically significant

The authors performed a systematic review and meta-analysis of all published randomized controlled trials with the aim to determine and quantify the anti-hyperglycemic effects of glutamine (Gln) in acute and chronic clinical settings.

The authors conducted a comprehensive search of all randomized clinical trials performed up to December 2018, to identify those investigating the impact of Gln supplementation on fasting blood sugar (FBS), insulin levels and homeostatic model assessment-insulin resistance (HOMA-IR) via ISI Web of Science, Cochrane library PubMed and SCOPUS databases. A meta-analysis of eligible studies was conducted using random effects model to estimate the pooled effect size. Fractional polynomial modeling was used to explore the dose–response relationships between Gln supplementation and diabetic indices.

The results of the present meta-analysis suggest that of Gln supplementation had a significant effect on FBS (weighted mean difference (WMD): –2.868 mg/dl, 95 per cent CI: –5.467, –0.269, p = 0.031). However, the authors failed to observe that Gln supplementation affected insulin levels (WMD: 1.06 units, 95 per cent CI: –1.13, 3.26, p = 0.34) and HOMA-IR (WMD: 0.001 units, 95 per cent CI: –2.031, 2.029, p = 0.999). Subgroup analyses showed that the highest decrease in FBS levels was observed when the duration of intervention was less than two weeks (WMD: –4.064 mg/dl, 95 per cent CI: –7.428, –0.700, p = 0.01) and when Gln was applied via infusion (WMD: –5.334 mg/dl, 95 per cent CI: –10.48, 0.17, p = 0.04).

The results from this meta-analysis show that Gln supplementation did not have a significant effect on insulin levels and HOMA-IR. However, it did significantly reduce the levels of FBS, obtaining a higher effect when the duration of the intervention period was less than two weeks.

In sharp contrast to television, various sources of market failure currently prevent market forces fulfilling the promise of digital switchover in radio markets. The purpose of this paper is to review the strengths and weaknesses, business models and market deployment of the two main platforms, with a view to establishing the economic case for higher regulatory involvement in digital radio markets.

The paper analyses the relevant broadcaster, engineering and regulatory literature, with particular emphasis on technical compatibilities among terrestrial radio broadcast technologies, and the technological and economic difficulties they face. The exercise is the first of its kind to scope and bring together these multidisciplinary contributions.

The highly uncoordinated development and deployment of terrestrial digital radio platforms is leading this new digital industry to an impasse. There is a legacy of uncertainty and scepticism amongst market players. Furthermore, prevailing technology and business models have marginalised community radio services and regional audiences.

The analysis does not cover the demand side (contents, culture) nor developments in non‐terrestrial digital platforms, nor in the US‐based IBOC standard.

There is considerable scope, particularly in large, sparsely inhabited countries with sizeable rural audiences to remedy the failings of the current fragmented approach through regulatory intervention through platform integration.

There is a lack of coherent information published on the potential benefits that the new digital platforms are bringing to the audio broadcasting market, and on the current market difficulties they face. The article remedies this gap.

The extent to which research into the design and development of environmental health indicators (EHIs) has translated into operational programmes is unclear. The purpose of this paper is to identify EHI initiatives worldwide, distil the EHIs and draw lessons from the experience.

A systematic internet-based review was undertaken. Programmes were selected for inclusion if they: first, had the ability to monitor both the physical environment and associated health outcomes; and second, the parent agency had the ability to influence policies related to the environment and health.

The small number of eligible programmes indicates EHI initiatives are not yet well established, especially in developing countries. The use of indicators was also limited by uncertainties in the exposure-response relationships that they implied, and the consequent inability to translate the indicators into a common measure of health impact. In addition, there is no information on the extent to which the indicators have been applied in decision making, nor on the policy implications of using indicators.

More effort is needed to encourage the development and use of more balanced and informative sets of indicators, and to evaluate their use and outcomes in terms of health benefits.

The time is right for a substantial review paper on EHIs as they are now being used by a number of organisations and to the knowledge this is the first review of operational EHI programmes worldwide.