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Few studies have been conducted in the cooling systems of power plants; they have focused on Naegleria fowleri, leaving a gap in the knowledge of other pathogenic free-living amoebae in this environment. The objective of this study was to determine the occurrence of saline-tolerant pathogenic Acanthamoeba in a geothermal power plant. The identification of isolated amoebae at genus level was carried out, observing their morphological characteristics; the determination of genotype and species of Acanthamoeba was performed via molecular biology (PCR). Water temperature ranged from 18 to 43 °C and conductivity from 4.0 × 104 to 8.7 × 104 µS/cm; this last value was greater than the seawater value. Only five amoeba genera were found. Acanthamoeba was in all the sampling sites, showing high saline tolerance. The high temperature, but mainly high conductivity, were the environmental conditions that determined the presence of pathogenic free-living amoebae in the hot water. All the strains of Acanthamoeba culbertsoni killed the mice, having a mortality of 40 to 100%. Acanthamoeba genotypes T10 and T5 were identified, T10 is rarely isolated from the environment, while T5 is more frequent. This is the first time that genotypes T5 and T10 have been reported in the environment in Mexico.

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[This corrects the article DOI: 10.3389/fphys.2022.867362.].

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Purpose: To investigate the effect of different water immersion temperatures on the kinetics of blood markers of skeletal muscle damage and the main leukocyte subpopulations. Methods: Eleven recreationally trained young men participated in four experimental sessions consisting of unilateral eccentric knee flexion and 90 min of treadmill running at 70% of peak oxygen uptake, followed by 15 min of water immersion recovery at 15, 28 or 38°C. In the control condition participants remained seated at room temperature. Four hours after exercise recovery, participants completed a performance test. Blood samples were obtained before and immediately after exercise, after immersion, immediately before and after the performance test and 24 h after exercise. The number of leukocyte populations and the percentage of lymphocyte and monocytes subsets, as well as the serum activity of creatine kinase and aspartate aminotransferase were determined. Results: Leukocytosis and increase in blood markers of skeletal muscle damage were observed after the exercise. Magnitude effect analysis indicated that post-exercise hot-water immersion likely reduced the exercise-induced lymphocytosis and monocytosis. Despite reduced monocyte count, recovery by 38°C immersion, as well as 28°C, likely increased the percentage of non-classical monocytes in the blood. The percentage of CD25+ cells in the CD4 T cell subpopulation was possibly lower after immersion in water at 28 and 15°C. No effect of recovery by water immersion was observed for serum levels of creatine kinase and aspartate aminotransferase. Conclusions: Recovery by hot-water immersion likely attenuated the leukocytosis and increased the mobilization of non-classical monocytes induced by a single session of exercise combining resistance and endurance exercises, despite no effect of water immersion on markers of skeletal muscle damage. The monocyte response mediated by hot water immersion may lead to the improvement of the inflammatory response evoked by exercise in the skeletal muscle.

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Hot water treatment (HT) induces chilling injury (CI) tolerance in mango, but prolonged exposure to HT causes softening. In this sense, calcium salts stabilize the cell wall. Nevertheless, there is little information on the effect of HT combined with calcium salts (HT-Ca) on calcium absorption and cell wall stability during storage of mango at CI temperature. We evaluated the effect of quarantine HT in combination with calcium chloride (CaCl2 ), calcium citrate (CaCit), or calcium lactate (CaLac) on calcium absorption, CI tolerance, and cell wall stabilization. HT and HT-CaCl2 had the lowest CI development. HT increased firmness loss and electrolyte leakage, and HT-Ca counteracted this effect. Overall, HT-Ca treatments had a similar effect on the cell wall degrading enzymes. HT-CaCl2 was the best treatment and did not present alterations on the epicuticular wax as observed on HT. HT-CaCl2 is a useful technology to stabilize cell wall and preserve mango during chilling storage. PRACTICAL APPLICATIONS: The addition of calcium salts in an established hot water quarantine procedure for mango exportation represents a viable alternative to counteract the negative effects of this thermal treatment upon cell microstructure, maintaining its positive effect of tolerance to chilling injury. In this sense, mango producers and packers can use a HT-CaCl2 treatment to reduce the presence of chilling injury and extent the fruit shelf life and improve its commercialization. Furthermore, technical and infrastructure changes are not necessary for the packaging chain.

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The search of sustainable and environmentally friendly alternatives to obtain compounds for different industrial sectors has grown exponentially. Following the principles of biorefinery and circular bioeconomy, processes in which the use of natural resources such as macroalgae biomass is prioritized are required. This review focuses on a description of the relevance, application and engineering platforms of hydrothermal systems and the operational conditions depending on the target as an innovative technology and bio-based solution for macroalgae fractionation in order to recover profitable products for industries and investors. In this sense, hydrothermal treatments represent a promising alternative for obtaining different high value-added compounds from this biomass; since, the different variations in terms of operating conditions, gives great versatility to this technology compared to other types of processing, allowing it to be adapted depending on the objective, whether it is working under sub/super critical conditions, thus expanding its field of application.

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The hemicellulosic fraction recovery is of interest for integrated processes in biorefineries, considering the possibility of high economic value products produced from their structural compounds of this polysaccharide. However, to perform an efficient recovery, it is necessary to use biomass fractionation techniques, and hydrothermal pretreatment is highlighted as a valuable technique in the hemicellulose recovery by applying high temperatures and pressure, causing dissolution of the structure. Considering the possibility of this pretreatment technique for current approaches to hemicellulose recovery, this article aimed to explore the relevance of hydrothermal pretreatment techniques (sub and supercritical water) as a strategy for recovering the hemicellulosic fraction from lignocellulosic biomass. Discussions about potential products to be generated, current market profile, and perspectives and challenges of applying the technique are also addressed.

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Ultrasound-assisted extraction (UAE) and pressurized hot water extraction (PHWE) were tested as advanced clean methods to obtain polysaccharides from Phoma dimorpha mycelial biomass. These methods were compared to conventional extraction (hot water extraction, HWE) in terms of polysaccharides-enriched fractions (PEF) yield. A central composite rotational design was performed for each extraction method to investigate the influence of independent variables on the yield and to help the selection of the condition with the highest yield using water as an extraction solvent. The best extraction condition of PEF yielded 12.02 wt% and was achieved when using UAE with direct sonication for 30 min under the intensity of 75.11 W/cm2 and pulse factor of 0.57. In the kinetic profiles, the highest yield (15.28 wt%) was obtained at 50 °C under an ultrasound intensity of 75.11 W/cm2 and a pulse factor of 0.93. Structural analysis of extracted polysaccharide was performed using Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and thermal property. The water solubility index, water holding capacity, and emulsification index of PEF were 31.3 ± 1.5%, 138.1 ± 3.2%, and 62.9 ± 2.3%, respectively. The submerged fermentation demonstrates the huge potential of Phoma dimorpha to produce polysaccharides with bioemulsifying properties as a biotechnologically cleaner alternative if compared to commercial petroleum-derived compounds. Furthermore, UAE and PHWE are green technologies, which can be operated at an industrial scale for PEF extraction.

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La epilepsia refleja por agua caliente es un tipo de convulsión poco frecuente cuya fisiopatología se desconoce. Estas crisis reflejas suelen iniciarse pocos segundos tras el contacto con el agua y, comúnmente, a temperaturas de 37-48 ºC. Los automatismos y las crisis parciales complejas, con o sin generalización secundaria, son el modo de manifestación principal.La exploración neurológica y el electroencefalograma intercrítico no suelen presentar alteraciones, lo que puede condicionar un retraso en el diagnóstico, por lo que es fundamental la sospecha clínica.El tratamiento antiepiléptico se inicia cuando se asocia a otro tipo de epilepsia o cuando ciertas medidas sencillas, como el descenso de la temperatura del agua en el baño, no controlan las crisis. Es posible la desaparición espontánea. Cuando es necesaria la terapéutica farmacológica, existe, normalmente, buena respuesta.Se presenta el caso de un lactante con diagnóstico de epilepsia refleja por agua caliente.

Hot-water epilepsy is a rare type of seizure whose pathophysiology is unknown. These reflex seizures usually begin a few seconds after contact with water, commonly at temperatures between 37-48 ºC. Automations and complex partial crises, with or without secondary generalization, are the main manifestation mode of this type of reflex epilepsies.Neurological examination and intercritical electroencephalography are usually normal, which may condition a delay in diagnosis, and the clinical suspicion is fundamental.Antiepileptic treatment is initiated when associated with another type of epilepsy or when certain simple measures, such as lowering the water temperature in the bath, do not control crises. Spontaneous disappearance is possible; when pharmacological therapy is necessary, there is usually a good response.We present the case of an infant diagnosed with hot-water epilepsy.

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Pressurized hot water extraction (PHWE), known as a "green" extraction technique, was used to obtain polysaccharide from the pulp of gabiroba (Campomanesia xanthocarpa Berg) fruits. The effects of pressure, temperature, and flow rate on pectin yields were analyzed through a full factorial design experiment 23. The optimal extraction conditions to achieve maximum pectin yield (5.70 wt%) were pressure of 150 bar, temperature of 120 °C, and flow rate of 1.5 mL min-1. The high pressure (100 bar) promoted an increase in galacturonic acid content (36.0%) compared to conventional hot water extraction (CEGP) with 25.7%. Differences in the proportion of homogalacturonan (HG) and rhamnogalacturonan (RG-I) domains ranging from 16.3 to 35.4% and 61.7 to 80.1%, respectively, were observed for each pectin sample according to the extraction conditions. The mono-dimensional (13C-NMR) and bi-dimensional (1H/13C HSQC-NMR) analyses confirmed the presence of HG and RG-I regions and indicated the presence of arabinogalactans type I (AG-I) and arabinogalactans type II (AG-II) in the PHWE pectin samples, which was not found for pectins from gabiroba pulp obtained by CEGP. The results showed that PHWE proved to be a promising method for extracting pectins from gabiroba fruits.

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The data presented in this article are related to the research article entitled "Solar domestic hot water regulation in the Latin American residential sector with the implementation of the Energy Performance of Buildings Directive: The case of Chile" (López-Ochoa et al., 2019), which evaluates the possibility of adapting Spanish solar domestic hot water regulations in Chile, with the objective of presenting the potential impact of the Energy Performance of Buildings Directive in Latin America. This dataset was made publicly available to show the possible energy savings with the thermal solar systems proposed to enable the use of these data by other researchers as well as designers, installers and decision-makers.