Coastal vegetated habitats can be important sinks of organic carbon (Corg) and mitigate global warming by sequestering significant quantities of atmospheric CO2 and storing sedimentary Corg for long ...periods, although their Corg burial and storage capacity may be affected by on-going sea level rise and human intervention. Geochemical data from published 210Pb-dated sediment cores, collected from low-energy microtidal coastal wetlands in El Salvador (Jiquilisco Bay) and in Mexico (Salada Lagoon; Estero de Urias Lagoon; Sian Ka'an Biosphere Reserve) were revisited to assess temporal changes (within the last 100years) of Corg concentrations, storage and burial rates in tropical salt marshes under the influence of sea level rise and contrasting anthropization degree. Grain size distribution was used to identify hydrodynamic changes, and δ13C to distinguish terrigenous sediments from those accumulated under the influence of marine transgression. Although the accretion rate ranges in all sediment records were comparable, Corg concentrations (0.2–30%), stocks (30–465Mgha−1, by extrapolation to 1m depth), and burial rates (3–378gm−2year−1) varied widely within and among the study areas. However, in most sites sea level rise decreased Corg concentrations and stocks in sediments, but increased Corg burial rates. Lower Corg concentrations were attributed to the input of reworked marine particles, which contribute with a lower amount of Corg than terrigenous sediments; whereas higher Corg burial rates were driven by higher mass accumulation rates, influenced by increased flooding and human interventions in the surroundings. Corg accumulation and long-term preservation in tropical salt marshes can be as high as in mangrove or temperate salt marsh areas and, besides the reduction of Corg stocks by ongoing sea level rise, the disturbance of the long-term buried Corg inventories might cause high CO2 releases, for which they must be protected as a part of climate change mitigation efforts.
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•210Pb-dated sediment cores from tropical saltmarshes showed marine transgression.•Corg concentration, stock and burial varied widely within and among study sites.•Corg stocks in tropical saltmarshes are as high as in other blue carbon ecosystems.•Marine transgression caused lower Corg sediment concentrations and stocks.•Sea level rise effects on Corg burial rates are masked by other global change impacts.
Continuous renal replacement techniques (CRRT) can induce complications and monitoring is crucial to ensure patient safety. We designed a prospective multicenter observational and descriptive study ...using the DIALYREG registry, an online database located on a REDCap web-based platform that allows real-time data analysis. Our main objective was to identify CRRT-related complications in our intensive care units (ICUs) and implement security measures accordingly. From January 2019 to December 2020, we included 323 patients with admission diagnoses of medical illness (54%), sepsis (24%), postoperative care (20%), and trauma (2%). CRRT indications were homeostasis (42%), oliguria (26%), fluid overload (15%), and hemodynamic optimization (13%). The median initial therapy dose was 30 ml/kg/h (IQR 25-40), and dynamic adjustment was performed in 61% of the treatments. Sets were anticoagulated with heparin (40%), citrate (38%) or no anticoagulation (22%). Citrate anticoagulation had several advantages: more frequent dynamic CRRT dose adjustment (77% vs. 58% with heparin and 56% without anticoagulation, p < 0.05), longer duration of set (median of 55 h, IQR 24-72 vs. 23 h, IQR 12-48 with heparin and 12 h, IQR 12-31 without anticoagulation, p < 0.05), less clotting of the set (26% vs. 46.7% with heparin, p < 0.05), and lower incidence of hypophosphatemia (1% citrate vs. 6% with heparin and 5% without anticoagulation). It was also safe and effective in subgroup analysis of patients with liver disease or sepsis. The main global complications were hypothermia (16%), hypophosphatemia (13%) and metabolic acidosis (10%). Weaning of the therapy was achieved through early discontinuation (56%), nocturnal therapy transition (26%) and progressive SLED (18%). 52% of the patients were discharged from the hospital, while 43% died in the ICU and 5% died during hospitalization. We can conclude that the DIALYREG registry is a feasible tool for real-time control of CRRT in our ICU.
Spatial and temporal variability of mercury concentrations in sediments was evaluated in 210Pb-dated sediment cores from offshore and intertidal areas in the southern Gulf of Mexico. In offshore ...cores, mercury concentrations were comparable (11.2–69.2 ng g−1), and intermediate between concentrations in intertidal cores from the eastern (6.0–34.4 ng g−1) and the western (34.9–137.7 ng g−1) inlets of Términos Lagoon. The enrichment factor (EF) indicated minimal contamination (EF < 2) in most offshore cores, whereas in some intertidal cores steadily increasing mercury enrichment and fluxes were observed along the past century. No evidence of oil industry related mercury contamination was found, as the minor but increasing enrichment in intertidal cores is most likely related to land-derived sources such as catchment eroded soils and waste water runoff. Results highlight the importance to control catchment erosion and untreated sewage releases to reduce mercury loadings to the coastal zone.
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•Hg contamination trends were studied in sediment cores of southern Gulf of Mexico.•Null to minor Hg enrichment was observed during the past 100 years in the area.•Recent Hg concentrations in most offshore cores were close to preindustrial levels.•Minor Hg contamination in intertidal areas is likely associated to surface runoff.•Hg concentrations are not a risk to benthic biota in the region.
River Atoyac is considered to be one of the most polluted rivers in Mexico due to the discharges of untreated or partially treated wastewater from industrial and municipal activities. In order to ...improve the river water quality, it is obligatory to identify the possible contaminant sources for upholding a well-balanced ecosystem. Henceforth, the present study incorporates the application of a continuous real-time monitoring system to identify the provenance of pollutants of the river mainly from anomaly events. Four monitoring stations were installed all along the River Atoyac in the State of Puebla, Central Mexico. The real-time monitoring systems have an ability to measure various water quality parameters for every 15 minutes such as Temperature (T), pH, Conductivity (EC), turbidity (TURB), Dissolved Oxygen (DO), Oxidation Reduction Potential (ORP) and Spectral Absorption Coefficient (SAC). In total, eight water samples of anomaly events (i.e.) 2 per monitoring station during rainy (August–September) and winter seasons (November–December), that were detected using the parameters previously mentioned were procured and also analyzed in the laboratory for evaluating almost 54 physicochemical, inorganic and organic characteristics. Statistical results of factorial analysis explained that 30% of the total variance corresponded to textile effluents, 23% related to discharges produced by automobile and petrochemical industries, and 18% of the total variance defined the agricultural activities. Additionally, indices like Overall Index Pollution, Heavy Metal Evaluation Index, Screening Quick Reference Table and Molecular ratios of hydrocarbons for PAH sources was also calculated to estimate the grade of pollution and associated ecotoxicological risks. The present study also enlightens the fact that the assessed results will definitely provide valuable information for the management of river water quality by developing stringent public policies by governmental agencies for the sustainable conservation of Atoyac River.
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•Real time monitoring is regarded to be a fundamental tool for wastewater management.•Identification of pollutant sources is vital to improve river water quality.•River Atoyac is highly impacted by industrial and agricultural effluents.•Pb, Hg and Cd reflect acute toxicity.
The objective of this study was to evaluate performance of a co-treatment method of industrial acid mine drainage (I-AMD) and municipal wastewater (MWW) by dual-chamber microbial fuel cells (DC-MFC). ...Sewage sludge and MWW were used as inoculum-fuel in anodic chamber. I-AMD was fed to the cathode side of the chamber. A 100 Ω resistor was used to externally connect the anode to the cathode (DC-MFC-A). A second cell was operated at the open circuit potential (DC-MFC-B). In both cells, the efficiency of organic matter removal was ~15% and the wastewater alkalinity was reduced by more than 50% in both cells. On the other hand, the physicochemical characteristics and composition of I-AMD were modified. The pH increased from 2.50 to 4.12 ± 0.6. The SO42− concentration was reduced ca. 20 and 8% for the DC-MFC-A and DC-MFC-B, respectively. NO3− Concentration decreased in both cells by >90%. Different heavy metals (HMs) and metalloid removal values were observed in the cells: 42, 84, 71, 77, 55 and 42% for Cd, Cu, Fe, Al, Pb and As, respectively. Finally, a maximum volumetric power of 14,000 mW/m3 was reached by DC-MFC-A. The DC-MFCs achieved simultaneous treatment of MWW, partial neutralization of I-AMD, HMs removal, and bioelectricity generation. Hence, DC-MFCs seem to be an encouraging alternative for bioremediation of both MWW and I-AMD.
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•Actual acid mine drainage and wastewater were co-treated by microbial fuel cells.•After 120 h, the pH of actual acid mine drainage increased from 2.50 up to 4.12.•High nitrates removal was observed (>90%) from actual acid mine drainage.•A maximum volumetric power of 14,000 mW/m3 was harvested using a hazardous effluent.•Cd, Cu, Fe, Al, Pb and As were removed by 42, 84, 71, 77, 55 and 42%, respectively.
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•Optimal conditions of oil extraction by thermosonication were found by RSM.•Thermosonication extraction improved oil yield and its quality was preserved.•Amplitude increase cause ...microstructural changes and reduce the crystallinity index•Structural changes in the residual cake caused by thermosonication were evidenced.
The seed of Ricinus communis L. is a source of oil that can be used to produce biodiesel. In this study, the thermosonication (TS) extraction of castor oil is proposed and is compared with Soxhlet (S) extraction as the conventional method. The optimum conditions for the TS extraction of castor oil were determined by response surface methodology (RSM). The time at 25, 35, and 45 min and amplitudes of 25, 50, and 75% were independent variables, while the dependent variables were the oil yield, iodine index, peroxide index, saponification index, unsaponifiable matter, acidity index, and refraction index. The optimal conditions for the oil yield were an amplitude of 50%, 35 min, and a solid/liquid ratio of 1/10 g/mL; a yield of 61.12% was reached under these conditions; by S extraction, the yield was 57.3% after 8 h of extraction. The microstructure of the residual cake before and after extraction was evaluated by scanning electron microscopy and the cellulosic compounds, proteins, and lipids in the residual cake were identified and their distribution observed by means of confocal laser scanning microscopy. Microscopy techniques and image analysis were helpful in evaluating the changes in the microstructure that occur on the residual cake during the TS and S extraction and to understand the extraction mechanisms. The crystallinity index was calculated from X-ray diffraction spectra to interpret changes in the structure of the residual cake before and after use of the extraction methods. Therefore, the TS extraction improved the oil yield in shorter extraction time. Characterization of the residual cake opens the way to study a potentially usable material as a source of cellulosic compounds.
•Agave leaves were fractionated by the Acetosolv method.•Microstructural changes during Acetosolv delignification were monitored by microscopy.•Cellulose crystallinity increased with the severity of ...the treatment operating conditions.•Phenomena occurring in the delignification of agave fibers are described.•Paper with a whiteness similar to commercial Bond paper was obtained.
The Acetosolv process is an organosolv treatment that has been used to separate cellulose, hemicellulose and lignin from lignocellulosic material by taking advantage of the higher affinity for the lignin oligomers to dissolve in organic solvents. However, the process conditions depend on the material used, thus the influence of process variables (time process, acetic acid concentration and hydrochloric acid concentration) on the Acetosolv delignification of agave leaves to obtain cellulose was evaluated. Using a face-centered factorial design, it was possible to obtain high quality pulp by the Acetosolv pulping process with the following results: pulp yield 24.5%; 8.2kappa number and a pulp viscosity of 571mL/g. The low kappa number values obtained indicate a high degree of whiteness and a low content of lignin cellulose; this has been confirmed by confocal and scanning electron microscopy while Raman spectroscopy and X-ray diffraction analyses indicate that the type of cellulose remaining in pulp is cellulose I. Paper with a similar or higher quality than commercial Bond paper in terms of whiteness could was obtained from Acetosolv pulp. A comprehensive and quantitative view of the phenomena occurring in the delignification of agave fibers using different characterization techniques is demonstrated.
•Microstructure of nopal spines was characterized by microscopy techniques.•Distribution of cellulose and lignin in nopal spines was evidenced by microscopy.•Micromechanical properties are influenced ...by the structural arrangement of spines.•Nopal spines are harder than wood materials.•Nopal spines could be an alternative source of cellulose and lignin.
The aim of this work was to study the microstructure and micromechanical properties of spines obtained from nopal waste. Spines were obtained by drying at 40 °C then sieving. Physical and chemical assays and microscopy techniques were used to determine the role of microstructural arrangement in local micromechanical properties. Transversal (TS) and longitudinal sections (LS) of the spines were studied by indentation and microscopy. Environmental scanning electron microscopy was helpful for characterizing the overall structure of spines. Confocal laser scanning microscopy was used for determining the distribution of cellulose and lignin in spines, which was associated with their micromechanical properties. Atomic force microscopy showed that TS is less rough (Ra = 3.08 ± 0.75 nm) and more hard (0.57 ± 0.31 GPa) than LS (Ra = 24.56 ± 1.60 nm, 0.57 ± 0.31 GPa). In accordance with these results, the elastic modulus of LS (8.65 ± 3.18 GPa) is lower than that of TS (14.94 ± 7.09 GPa). The hardness and elastic modulus of libriform fibers and sclerified epidermis are influenced by their microstructures and as well as the distribution of cellulose and lignin in the spines. The microstructural arrangement and the distribution of cellulose and lignin in the TS provide greater hardness values than those of woods. The current study presents a novel structural characterization of nopal spines and their local micromechanical properties. This waste product could be a cheap and non-wood alternative resource of cellulose with good mechanical properties useful for designing novel biomaterials with applications in the agricultural sector.
The kidney undergoes structural and physiological changes with age, predominantly studied in glomeruli and proximal tubules. However, limited knowledge is available about the impact of aging and ...anti-aging interventions on distal tubules. In this study, we investigated the effects of cytochrome b5 reductase 3 (CYB5R3) overexpression and/or dietary nicotinamide riboside (NR) supplementation on distal tubule mitochondria. Initially, transcriptomic data were analyzed to evaluate key genes related with distal tubules, CYB5R3, and NAD+ metabolism, showing significant differences between males and females in adult and old mice. Subsequently, our emphasis focused on assessing how these interventions, that have demonstrated the anti-aging potential, influenced structural parameters of distal tubule mitochondria, such as morphology and mass, as well as abundance, distance, and length of mitochondria-endoplasmic reticulum contact sites, employing an electron microscopy approach. Our findings indicate that both interventions have differential effects depending on the age and sex of the mice. Aging resulted in an increase in mitochondrial size and a decrease in mitochondrial abundance in males, while a reduction in abundance, size, and mitochondrial mass was observed in old females when compared with their adult counterparts. Combining both the interventions, CYB5R3 overexpression and dietary NR supplementation mitigated age-related changes; however, these effects were mainly accounted by NR in males and by transgenesis in females. In conclusion, the influence of CYB5R3 overexpression and dietary NR supplementation on distal tubule mitochondria depends on sex, genotype, and diet. This underscores the importance of incorporating these variables in subsequent studies to comprehensively address the multifaceted aspects of aging.The kidney undergoes structural and physiological changes with age, predominantly studied in glomeruli and proximal tubules. However, limited knowledge is available about the impact of aging and anti-aging interventions on distal tubules. In this study, we investigated the effects of cytochrome b5 reductase 3 (CYB5R3) overexpression and/or dietary nicotinamide riboside (NR) supplementation on distal tubule mitochondria. Initially, transcriptomic data were analyzed to evaluate key genes related with distal tubules, CYB5R3, and NAD+ metabolism, showing significant differences between males and females in adult and old mice. Subsequently, our emphasis focused on assessing how these interventions, that have demonstrated the anti-aging potential, influenced structural parameters of distal tubule mitochondria, such as morphology and mass, as well as abundance, distance, and length of mitochondria-endoplasmic reticulum contact sites, employing an electron microscopy approach. Our findings indicate that both interventions have differential effects depending on the age and sex of the mice. Aging resulted in an increase in mitochondrial size and a decrease in mitochondrial abundance in males, while a reduction in abundance, size, and mitochondrial mass was observed in old females when compared with their adult counterparts. Combining both the interventions, CYB5R3 overexpression and dietary NR supplementation mitigated age-related changes; however, these effects were mainly accounted by NR in males and by transgenesis in females. In conclusion, the influence of CYB5R3 overexpression and dietary NR supplementation on distal tubule mitochondria depends on sex, genotype, and diet. This underscores the importance of incorporating these variables in subsequent studies to comprehensively address the multifaceted aspects of aging.
► Chemical, physical and morphological properties of
R. communis were evaluated by microscopy and image analysis. ► Size and shape descriptors allow characterize endosperm, embryo cells and lipid ...bodies of seeds. ► Numerical data integrate information useful for thermal and mechanical processing of
R. communis seed. ► Microscopy and images analysis were efficient for the characterization of macro and microstructure of seeds and understanding of their relationships properties–structure.
Ricinus communis seed is a source of protein and oil with a high potential to use as animal's feedstock and biodiesel production. However, the oil yield and the extraction efficiency depend on the process conditions applied, as well as on the physical, chemical and structural properties of the seed, which have not been fully investigated. Hence, the objective of this study was to evaluate some chemical and physical properties of
R. communis seed as well as to describe and quantify the macro and microstructure of this raw material by microscopy techniques and image analysis. Chemical analysis confirmed the seeds’ high contents of protein (28.48
±
0.25%) and fat (51
±
0.31%). On the other hand, the values of geometric mean diameter (8.95
±
0.05
mm), bulk density (538
±
11
kg/m
3), and true density (1458
±
27
kg/m
3), among others, were higher than the ones reported about similar oils seeds. Microstructural studies showed that the endosperm cells presented an ovoid shape, as obtained from the aspect ratio results (AR
=
1.28
±
0.17), and a cell density of 570
±
10
cell/mm
2, resulting in a porous structure, while the embryo cells had a cell density of 4903
±
2
cell/mm
2, and an AR of 2.41
±
0.48, related to a more compact structure (rectangular form) in this part of the seed. Regarding to lipids bodies (lb), they were only visible in the endosperm cells, showing a circular shape (AR
=
1.16
±
0.1), and a mean cell density of 9.57
±
2.40
lipid
bodies/μm
2, associated to protein as observed by the mineral presence (K, P, Mg and S) as determined by the energy dispersive X-ray analysis. Microscopy techniques and images analysis were efficient tools for the characterization of macro and microstructure of seeds and the data obtained integrate numerical information that could be useful for thermal and mechanical processing of
R. communis seed, as well as for the design process equipment.
