Assessment of temperature dynamics during methane oxidation in a pilot scale compost biofilter.

Biological methane oxidation can sustain high temperatures in organic matrices, such as landfill covers and compost biofilters. This study investigates the temperature dynamics, methane removal efficiency, and microbial community responses in a pilot scale compost biofilter under three methane concentrations (2, 4, and 8 % v v in air) with a 23-minute empty bed residence time. Complete methane removal was achieved at 2 %, with compost bed temperatures reaching 51 °C.

Traditional and new trend strategies to enhance pigment contents in microalgae.

Microalgae are a source of a wide variety of commodities, including particularly valuable pigments. The typical pigments present in microalgae are the chlorophylls, carotenoids, and phycobiliproteins. However, other types of pigments, of the family of water-soluble polyphenols, usually encountered in terrestrial plants, have been recently reported in microalgae.

Follow-up of telemedicine mental health interventions amid COVID-19 pandemic.

The initiation of the program Mental Health Support Program for Coronavirus Infection addressed the increased demand for mental health services in the province of Salamanca, resulting from the COVID-19 pandemic. The psychiatry service provided care for COVID-19 patients, their families, and healthcare workers who treated them, as these groups were identified as being at risk. This study aims to describe the assistance provided, including personnel and resources utilized, types of interventions carried out, and to assess the demand for mental health care and predominant symptoms and emotions experienced by patients.

Biogas Purification through the use of a Microalgae-Bacterial System in Semi-Industrial High Rate Algal Ponds.

In recent years, a number of technologies have emerged to purify biogas into biomethane. This purification entails a reduction in the concentration of polluting gases such as carbon dioxide and hydrogen sulfide to increase the content of methane. In this study, we used a microalgal cultivation technology to treat and purify biogas produced from organic waste from the swine industry to obtain ready-to-use biomethane.

[Cognitive, Emotional and Dependency Level on Institutionalized Older Adults].

Introduction: It is necessary to analyze the aging process in institutionalized older people. For this purpose, a descriptive and analytical epidemiological study was carried out in nursing homes for older adults before the COVID-19 pandemic.

Objective: Provide an in-depth insight into cognitive (MEC), emotional (Geriatric Depression Scale), and functional (Barthel Scale) status within the older adult participants.

New cut-off points of PHQ-9 and its variants, in Costa Rica: a nationwide observational study.

The PHQ-9 questionnaire is a screening test worldwide used to measure depression. But it cannot be used in Costa Rica, due to the fact that it has not previously been validated for its population. The present study aims to show the validation of the PHQ-9 questionnaire and its variants (PHQ-2, PHQ-4, PHQ-8) in a population sample of adults residing in Costa Rica.

Short-term tuning of microalgal composition by exposition to different irradiance and small doses of sulfide.

Suitability of microalgae valorization mainly depends on its biochemical composition. Overall, among all microalgal derivatives, pigments currently stand out as the major added-value component. While it is well recognized that microalgal growth conditions strongly affect biomass composition, final tuning of already grown microalgae has been scarcely studied.

The challenge of community mental health interventions with patients, relatives, and health professionals during the COVID-19 pandemic: a real-world 9-month follow-up study.

Since the beginning of the COVID-19 pandemic, the need to implement protocols that respond to the mental health demands of the population has been demonstrated. The PASMICOR programme started in March 2020, involving a total of 210 requests for treatment. Out of those subjects, the intervention was performed in 53 patients with COVID-19 without history of past psychiatric illness, 57 relatives and 60 health professionals, all of them within the area of Salamanca (Spain).

Impact on Sleep Quality, Mood, Anxiety, and Personal Satisfaction of Doctors Assigned to COVID-19 Units.

The SARS-CoV-2 health emergency has led to a restructuring of health care systems and the reassignment of medical specialists from their usual duties to attend COVID-19 patients. The aim of this paper is to describe the levels of insomnia, anxiety, depression, and the impact on quality of life of doctors who were on the frontline of COVID-19 during the first two waves of the pandemic. Self-report surveys were conducted on said physicians during both waves, with 83 and 61 responses in the first and second waves, respectively.

Microalgae Biomass as a New Potential Source of Sustainable Green Lubricants.

Lubricants are materials able to reduce friction and/or wear of any type of moving surfaces facilitating smooth operations, maintaining reliable machine functions, and reducing risks of failures while contributing to energy savings. At present, most worldwide used lubricants are derived from crude oil. However, production, usage and disposal of these lubricants have significant impact on environment and health.

Strategies for decreasing the O content in the upgraded biogas purified via microalgae-based technology.

Microalgae-bacteria consortium based technology using a High Rate Algal Pond (HRAP) interconnected to an Absorption Bubble Column (ABC) has emerged as an environmentally friendly promising option to upgrade biogas. However, the oxygenic photosynthesis of microalgae induces oxygen contamination in upgraded biogas, which could limit its further applications. Several strategies were proposed to favor the oxygen desorption and oxygen uptake in parts and accessories of the upgrading system.

Photorespiration in an outdoor alkaline open-photobioreactor used for biogas upgrading.

The rates of oxygenic and carbon fixation photosynthetic processes of a microalgae consortium were simultaneously evaluated under steady-state performance in an bench scale alkaline open-system exposed to outdoor conditions in Mexico City. A synthetic methane-free gaseous stream (SMGS) similar to biogas was used as inorganic carbon source and model of biogas upgrading. The microalgae CO fixation rates were calculated through a novel methodology based on an inorganic carbon mass balance under continuous scrubbing of a SMGS similar to biogas, where the influence of pH and temperature time-depended oscillations were successfully incorporated into the mass balances.

Evaluation of a hybrid physicochemical/biological technology to remove toxic HS from air with elemental sulfur recovery.

The removal of toxic hydrogen sulfide (HS) from the air at pilot-scale with elemental sulfur recovery was evaluated using Fe-EDTA chelate as a single treatment at a pH of about 8.5. This was later combined with a compost biofiltration process for polishing the pre-treated air.

A study of photosynthetic biogas upgrading based on a high rate algal pond under alkaline conditions: Influence of the illumination regime.

Microalgal-bacterial processes have emerged as environmental friendly systems for the cost-effective treatment of anaerobic effluents such as biogas and nutrients-laden digestates. Environmental parameters such as temperature, irradiation, nutrient concentration and pH effect the performance of the systems. In this paper, the potential of a microalgal-bacterial photobioreactor operated under high pH (≈9.

Fate of HS during the cultivation of Chlorella sp. deployed for biogas upgrading.

The HS may play a key role in the sulfur cycle among the biogas production by the anaerobic digestion of wastes and the biogas upgrading by a microalgae based technology. The biogas is upgraded by contacting with slightly alkaline aqueous microalgae culture, then CO and HS are absorbed. The dissolved HS could limit or inhibit the microalgae growth.

Effect of microalgae inoculation on the start-up of microalgae-bacteria systems treating municipal, piggery and digestate wastewaters.

The effect of the inoculation of a microalgae-bacteria system on the removal of nutrients and organic matter using municipal, piggery and digestate wastewaters was evaluated. Three conditions for each substrate were evaluated: (1) inoculation with activated sludge and illumination, (2) inoculation with activated sludge without illumination, and (3) inoculation with activated sludge plus a native microalgae consortium under illumination. The illuminated reactors that were inoculated only with activated sludge developed microalgae after 12 operation days.

Microalgal-biotechnology as a platform for an integral biogas upgrading and nutrient removal from anaerobic effluents.

The potential of a pilot high rate algal pond (HRAP) interconnected via liquid recirculation with an external absorption column for the simultaneous removal of H2S and CO2 from biogas using an alkaliphilic microalgal-bacterial consortium was evaluated. A bubble column was preferred as external absorption unit to a packed bed column based on its ease of operation, despite showing a comparable CO2 mass transfer capacity. When the combined HRAP-bubble column system was operated under continuous mode with mineral salt medium at a biogas residence time of 30 min in the absorption column, the system removed 100% of the H2S (up to 5000 ppmv) and 90% of the CO2 supplied, with O2 concentrations in the upgraded biogas below 0.

Development of a kinetic model for elemental sulfur and sulfate formation from the autotrophic sulfide oxidation using respirometric techniques.

A kinetic model for the elemental sulfur and sulfate production from the autotrophic sulfide oxidation has been proposed. It is based on two kinetic equations able to describe the simultaneous microbial consumption of oxygen and sulfide (OUR and SUR) as a function of a particular sulfide-oxidizing microorganism or its physiological state, these can be characterized by the assessment of their kinetic constants. The respirometric technique allowed to estimate the dynamic experimental OUR and SUR profiles, which were used to calibrate the kinetic model.

Alkaline biofiltration of H2S odors.

Hydrogen sulfide (H2S) is a very common odor nuisance which is best controlled by chemical or biological scrubbing. Under alkaline pH, the amount of H2S that can be solubilized in a scrubbing liquid increases significantly, and therefore, gas-liquid mass transfer limitations can be reduced. To date, biological scrubbing of H2S has been limited to neutral or acidic pH, despite the potential benefit of reduced mass transfer limitations at alkaline pH.

Evaluation of feed COD/sulfate ratio as a control criterion for the biological hydrogen sulfide production and lead precipitation.

The ability of sulfate-reducing bacteria to produce hydrogen sulfide and the high affinity of sulfide to react with divalent metallic cations represent an excellent option to remove heavy metals from wastewater. Different parameters have been proposed to control the hydrogen sulfide production by anaerobic bacteria, such as the organic and sulfate loading rates and the feed COD/SO4(2-) ratio. This work relates the feed COD/SO4(2-) ratio with the hydrogen sulfide production and dissolved lead precipitation, using ethanol as carbon and energy source in an up-flow anaerobic sludge blanket reactor.