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In August 2021, the Mar Menor, a saltwater lagoon located in the Region of Murcia (Spain), suffered a tragic environmental episode of dystrophic crisis and anoxia. The appearance of numerous dead fish in different areas of the lagoon over the course of days put all the authorities and the population of the area on alert. This paper shows a case study of what happened in the lagoon in terms of the presence of the most common inorganic pollutants. Measurements of the concentration of nitrogen species, phosphates and main heavy metals were carried out at different sampling sites in the Mar Menor from May 2021 to November 2022. Chemical analyses were carried out for each of the species under study. These analyses provide valuable information about the dystrophic crisis caused by a classic eutrophication process that began with the excessive nutrient input into the Mar Menor. Ion chromatography and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) were used as instrumentation for the quantification of these samples. The species whose values were greatly increased after the tragic episode described above were nitrates. The concentration varied significantly at the different sampling sites throughout the study. On the last sampling date, decreased concentrations of all the species were measured at each of the sampling sites, coinciding with the apparent good state of the lagoon. [ABSTRACT FROM AUTHOR]

Divalent mercury (Hg (II)) is the predominant mercury species in aquatic environments. Hg (II) combines easily with human enzymes, thus causing acute diseases, even at very low concentrations. Among existing procedures to remove Hg (II) from water, adsorption is widely used, achieving high removal efficiencies. However, most actual adsorption techniques require high temperatures, long times or tedious procedures. Here we present a novel, simple and fast method to remove Hg (II) from wastewater by using magnetic-core nanoparticles coated with metallic silver and functionalized with sodium 2-mercaptoethane sulfonate. This adsorbent was characterized by field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy and Brunauer–Emmett–Teller analysis, which showed a contact surface area of the adsorbent equal to 116.476 m2/g. The equilibrium isotherm is characterized by the Langmuir model. Results show that 100% adsorption efficiency is achieved in 30 seconds of contact time, at pH 6.2 and room temperature, employing a low dose of adsorbent. The adsorbent can be recovered and recycled, keeping 100% adsorption efficiency for two additional cycles. The presence of other ions commonly found in aqueous media does not interfere with Hg (II) adsorption. [ABSTRACT FROM AUTHOR]

Although all authors report beneficial health changes following training based on the Pilates method, no explicit analysis has been performed of its cardiorespiratory effects. The objective of this study was to evaluate possible changes in cardiorespiratory parameters with the Pilates method. A total of 45 university students aged 18–35 years (77.8% female and 22.2% male), who did not routinely practice physical exercise or sports, volunteered for the study and signed informed consent. The Pilates training was conducted over 10 weeks, with three 1-hour sessions per week. Physiological cardiorespiratory responses were assessed using a MasterScreen CPX apparatus. After the 10-week training, statistically significant improvements were observed in mean heart rate (135.4–124.2 beats/min), respiratory exchange ratio (1.1–0.9) and oxygen equivalent (30.7–27.6) values, among other spirometric parameters, in submaximal aerobic testing. These findings indicate that practice of the Pilates method has a positive influence on cardiorespiratory parameters in healthy adults who do not routinely practice physical exercise activities. [ABSTRACT FROM AUTHOR]