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In recent years, a number of alternatives for service differentiation and QoS provision have been proposed and standardized in communication networks. In the case of back‐bone networks the DiffServ architecture has prevailed, due to its scalability and deployment feasibility. The provisioning of differentiated services has raised the requirements for interdependent controlled resource allocation and service pricing, with particular needs for pricing mechanisms that preserve the potential and flexibility of the DiffServ framework. At the same time, such mechanisms should reflect resource usage, allocate resources efficiently, reimburse costs or maximize service provision profits and lead customers to requesting services that will maximize their revenue. Presents the key issues involved in the area of pricing DiffServ‐based services and the research work carried out in this field, while at the same time outlining the basic principles that such a pricing infrastructure should obey with respect to the particularities that apply to the case of DiffServ services provision.

The determination of mode-I fracture toughness of brittle structural materials by means of the notched Brazilian disc configuration is studied. Advantage is taken of a recently introduced analytical solution and, also, of data provided by an experimental protocol with notched marble specimens under diametral compression using the loading device suggested by International Society for Rock Mechanics (ISRM) and also the three-dimensional digital image correlation (3D-DIC) technique.

The analytical solution highlighted the role of geometrical factors, like, for example, the width of the notch, which are usually disregarded. The data of the experimental protocol were comparatively considered with those concerning the response of the specific material under uniaxial tensile load.

This combined study provided interesting data concerning some open issues, as it is the exact crack initiation point and the level of the critical load causing crack initiation. It was definitely indicated that the crack initiation point is not a priori known (even for notched specimens) and, also, that the maximum recorded load does not correspond by default to the critical load responsible for the onset of catastrophic macroscopic fracture.

It was suggested that the load considered critical one for the determination of mode-I fracture toughness K_IC is erroneous. At a load equal to about 70% of the maximum one, a process zone is formed (zone of non-reversible phenomena) around the notch's crown, designating termination of the validity of any linear elastic solution used to determine the normalized stress intensity factors (SIFs). Moreover, at a load level equal to about 95% of the macroscopically observed fracture load, crack propagation has already begun. Therefore, the experimental procedure must be monitored with additional equipment, providing an overview of the displacement field developed during loading.

No current psychotherapeutic intervention is designed to enhance job retention in employees with moderate–severe recurrent depression. The aim of this study is to test the feasibility of a new, interdisciplinary work-focused relational group cognitive behavioural therapy (CBT) treatment programme for moderate–severe depression.

The programme was based on a theoretical integration of occupational stress, psychological, social/interpersonal and bio-medical theories. It consisted of up to four 1:1 psychotherapy sessions; 12 work-focused, full-day, weekly CBT sessions facilitated by a cognitive behavioural therapist and occupational therapist; and up to four optional 1:1 sessions with an occupational therapist. Depression severity (primary outcome) and a range of secondary outcomes were assessed before (first CBT session) and after (twelfth CBT session) therapy using validated instruments.

Eight women (26–49 years) with moderate–severe depression participated. Five were on antidepressant medication. While there was no statistically significant change in Hamilton Depression Rating Scale depression scores after therapy (n = 5; p = 0.313), Beck Depression Inventory-II depression scores significantly decreased after therapy (n = 8; –20.0 median change, p = 0.016; 6/8 responses, 7/8 minimal clinically important differences, two remissions). There were significant improvements in the secondary outcomes of overall psychological distress, coping self-efficacy, health-related quality of life and interpersonal difficulties after therapy. All clients in work at the start of therapy remained in work at the end of therapy. The intervention was safe and had 100% retention.

A major limitation was recruitment shortfall, resulting in a small sample of middle-aged women, which reduces representativeness and increases the possibility of methodological weaknesses in terms of the statistical analysis. A definitive trial would need much larger samples to improve statistical power and increase confidence in the findings. Another major limitation was that two of the authors were involved in delivering the intervention such that its generalisability is uncertain.

This novel programme was evaluated and implemented in the real world of clinical practice. It showed promising immediate positive outcomes in terms of depressive symptoms, interpersonal difficulties and job retention that warrant further exploration in a longer-term definitive study.

Empirical studies focused on enhancing job retention in employees with moderate–severe recurrent depression are lacking, so this study was highly relevant to a potentially marginalised community.

While limited by a recruitment shortfall, missing data and client heterogeneity, this study showed promising immediate positive outcomes for the new programme in terms of depressive symptoms, interpersonal difficulties and job retention that warrant exploration in a definitive study.