Long-Term Performance of a Hybrid-Flow Constructed Wetlands System for Urban Wastewater Treatment in Caldera de Tirajana (Santa Lucía, Gran Canaria, Spain).

This paper describes the results that have been obtained in a real case study of a hybrid constructed wetlands system, which has been in continuous operation for over 11 years. The main aim of the study was to understand the long-term operation and efficiency of the system (which is situated in the municipality of Santa Lucía, Gran Canaria, Spain), which comprises two vertical-flow and one horizontal-flow constructed wetlands for the treatment of urban wastewater. The system, which was originally designed to treat a flow rate of 12.5 m3/day, with a load of 100 equivalent inhabitants, has been operating since its inauguration (July 2008), with a flow rate of almost 35 m3/day and a load of 400 equivalent inhabitants. Despite this, the mean total removal efficiencies during the study period (2014-2019) are optimal for a system of these characteristics, as follows: 92% for 5-day biochemical oxygen demand (BOD5), 89% for the chemical oxygen demand (COD), and 97% for the total suspended solids (TSS). The system efficiency, with respect to nutrient removal, was somewhat lower, resulting in 48% for total N and 35% for NH4. It has been confirmed with this study that this type of system is an appropriate, robust, resilient nature-based solution for the treatment of the wastewater that is generated in small communities, especially in zones with a warm climate, stable mean temperatures, and mild winters.

Schwannoma: Differential diagnosis of a subepithelial gastric lesion. Two case report.

The pre-operative differential diagnosis of gastric subepithelial lesions is complex. We can find pathologies with a very different behavior. Some of them, like gastrointestinal (GI) stromal tumors, can present a malignant behavior, and others like schwannomas are practically benign. Schwannomas of the GI tract originate from the Schwann cells of the Auerbach plexus and their most frequent location is the stomach. The definitive diagnosis is made by immunohistochemical analysis of the surgical specimen and its resection is curative. We report two cases of gastric subepithelial lesions with a definitive diagnosis of schwannoma.

El diagnóstico diferencial preoperatorio de las lesiones subepiteliales gástricas es complejo. Podemos encontrar patologías con un comportamiento muy diferente. Algunas de ellas, como los GIST (gastrointestinal stromal tumours), pueden presentar un comportamiento maligno, y otras, como los schwannomas, son prácticamente benignas. Los schwannomas del tracto gastrointestinal se originan de las células de Schwann del plexo de Auerbach y su localización más frecuente es el estómago. El diagnóstico definitivo se realiza mediante el análisis inmunohistoquímico de la pieza quirúrgica, y su resección es curativa. Reportamos dos casos de lesiones subepiteliales gástricas con diagnóstico definitivo de schwannoma.