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In this article, a dielectric-only reflectarray (RA) with a wideband behavior is proposed as an alternative to conventional metallo-dielectric configurations. The introduced unit-cell (UC) consists of a single dielectric layer perforated with a square hole located at the center, whose size is used to control the phase of the reflection coefficient. For such a dielectric element, an accurate equivalent circuit model for predicting the reflection coefficient is derived by combining two different concepts: the effective medium theory used to characterize the effective permittivity and the Floquet modal expansion to describe the wave propagation in terms of Floquet modes. The UC geometrical parameters are then optimized to maximize the RA performance, taking also into account the limitations introduced by the additive manufacturing (AM) process adopted for the realization of a prototype. Its experimental characterization confirms the effectiveness of the UC, of the design and manufacturing procedures: in fact, the measurements, in very good agreement with the results of the simulations, prove the significantly low sidelobe levels, the good aperture efficiency, and the excellent 1-dB bandwidth (BW), larger than 24%.

As the impacts of climate change intensify, potential relocation is becoming more of a reality for coastal communities throughout the world. This is furthering the demand for the implementation of governance relocation frameworks. In order to stay true to the principles of environmental justice while at the same time ensuring an effective policy that meets the needs and wants of affected communities, an adaptive relocation framework requires collaboration between state and non-state actors. It is thus important to pay attention to how non-state actors are incorporated into public participatory climate change adaptation efforts. In order to affectively address previous limitations of public participation, stakeholders must pay attention to already existing power systems. Through a case study approach of a village relocation project in Fiji, I examine the role of power in a climate change adaptation plan that involved the community of Vunidogoloa, local government, and national government stakeholders. I employ Steven Lukes’s three-dimensional framework of power to the case of Vunidogoloa, a Fijian village that relocated inland due to coastal erosion and shoreline flooding, to illustrate how the political arrangement of participation reinforced existing hierarchies between the village and the government.

By building on the existing literature of social capital and ethics in economics, we present a stylised theoretical framework of civil society and solidarity economy that is based on three main assumptions: 1) agents voluntary engage in civil (economic) activities that maximise the community welfare (we-rationality); 2) the higher the engagement of initial pioneers, the more cooperation is likely to spread in the society (social reciprocity); 3) wide-spread trust is a co-product of the virtuous diffusion of cooperative behaviours and its existence represents an important factor of economic growth. The second part of the paper focuses on the innovative project of solidarity economy in Latin America as a valid empirical application of the distinguished characteristics of the concept of civil society in the economic sphere.

Until the eighties chemiolysis represented the only alternative to surgery in the treatment of reno-ureteral stones. Nowadays it successfully used as debulking pre ESWL or to eliminate residual or ureteral fragments, even after unsuccessful percutaneous or ureteroscopic treatments. We report our experience on instrumental chemiolysis as elective procedure in selected patients.

Our experience over the last 5 years has been reviewed to assess the therapeutic choices in relation to the age of patients with bladder tumour. The results of TURB, partial cystectomy + radiotherapy (RV) and radical cystectomy (CX) were compared. Patients subjected to RV were on average older (69.9 years) than those treated by TURB and CX (67.6 and 65.3 years).

We report a case of incomplete retention of urine, with normal cystometric reports but with cervical obstruction. The reason for obstruction was identified in a circular, concentric flap of mucosa sliding into the urethra from the bladder neck causing an occlusion of the urethra. The pathology was resolved by the endoscopical resection of the mucosa.