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The e-commerce boom presents new challenges for last-mile delivery (LMD), which may be mitigated by new delivery technologies. This paper evaluates the impact of mobile parcel lockers (MPL) on costs and CO₂ equivalent (CO₂e) emissions in existing LMD networks, which include home delivery and shipments to stationary parcel lockers.

To describe customers’ preferences, we design a multinomial logit model based on recipients’ travel distance to pick-up locations and availability at home. Based on route cost estimation, we define the operating costs for MPLs. We devise a mathematical model with binary decision variables to optimize the location of MPLs.

Our study demonstrates that integrating MPLs leads to additional cost savings of 8.7% and extra CO₂e emissions savings of up to 5.4%. Our analysis of several regional clusters suggests that MPLs yield benefits in highly populous cities but may result in additional emissions in more rural areas where recipients drive longer distances to pick-ups.

This paper designs a suitable operating model for MPLs and demonstrates environmental and economic savings. Moreover, it adds recipients’ availability at home to receive parcels improving the accuracy of stochastic demand. In addition, MPLs are evaluated in the context of several regional clusters ranging from large cities to rural areas. Thus, we provide managerial guidance to logistics service providers how and where to deploy MPLs.

The present study aims to bring out the impact of consanguinity on spontaneous pregnancy loss (SPL) and on descendants’ health, among the population of north Morocco.

Convenience sampling was used for collecting data. A questionnaire was randomly administered to 385 couples represented by either the husband, the wife or both. The study lasted for three months, from January to March 2015.

In total, 238 valid questionnaires were analysed. The results showed that the consanguinity rate was 45.23% and that most consanguineous unions were between first cousins (91%). Data analysis revealed that SPL risk was similar in consanguineous and non-consanguineous couples (OR = 1.6; IC95% = 0.9–2.9). Also, no significant difference was observed in terms of SPL type (OR = 1.6; IC95% = 0.7–3.9) and frequency (p = 0.81). However, late SPL frequency was significantly lower in consanguineous couples (p < 0.001), whereas no significant difference was registered in terms of early SPL frequency (p = 0.73). On the other hand, consanguineous couples displayed a significantly higher risk of descendants’ health disorders in comparison with non-consanguineous ones. Moreover, the consanguineous couples had a significantly higher number of children with health disorders (p < 0.001). The risk analysis also showed that consanguineous couples displayed a significantly higher risk of congenital malformations (OR = 7.23; IC95% = 3.52–14.84) and multifactorial diseases (OR = 3.72; IC95% = 1.46–9.49), but no significant difference was observed in terms of behavioural disorders risk.

The population awareness regarding the negative effects of consanguinity should be raised through education programmes and premarital, prenatal and genetic counselling services.

This study aims to analyse the non-linear losses of a porous media (stack) composed by parallel plates and inserted in a resonator tube in oscillatory flows by proposing numerical correlations between pressure gradient and velocity.

The numerical correlations origin from computational fluid dynamics simulations, conducted at the microscopic scale, in which three fluid channels representing the porous media are taken into account. More specifically, for a specific frequency and stack porosity, the oscillating pressure input is varied, and the velocity and the pressure-drop are post-processed in the frequency domain (Fast Fourier Transform analysis).

It emerges that the viscous component of pressure drop follows a quadratic trend with respect to velocity inside the stack, while the inertial component is linear also at high-velocity regimes. Furthermore, the non-linear coefficient b of the correlation ax + bx² (related to the Forchheimer coefficient) is discovered to be dependent on frequency. The largest value of the b is found at low frequencies as the fluid particle displacement is comparable to the stack length. Furthermore, the lower the porosity the higher the Forchheimer term because the velocity gradients at the stack geometrical discontinuities are more pronounced.

The main novelty of this work is that, for the first time, non-linear losses of a parallel plate stack are investigated from a macroscopic point of view and summarised into a non-linear correlation, similar to the steady-state and well-known Darcy–Forchheimer law. The main difference is that it considers the frequency dependence of both Darcy and Forchheimer terms. The results can be used to enhance the analysis and design of thermoacoustic devices, which use the kind of stacks studied in the present work.