Total Anion Research Articles

Polystyrene microplastics exposition on human placental explants induces time-dependent cytotoxicity, oxidative stress and metabolic alterations.

Microplastics (MPs) are environmental pollutants that pose potential risks to living organisms. MPs have been shown to accumulate in human organs, including the placenta. In this study, we investigated the biochemical impact of 5 μm polystyrene microplastics (PS-MPs) on term placental chorionic villi explants, focusing on cytotoxicity, oxidative stress, metabolic changes, and the potential for MPs to cross the placental barrier. Term placental chorionic explants were cultured for 24 hours with varying concentrations of PS-MPs, with MTT assays used to determine the appropriate concentration for further analysis. Cytotoxicity was assessed using the lactate dehydrogenase (LDH) release assay over a period of up to 72 hours. Reactive oxygen species formation and antioxidant activity were evaluated using biochemical assays. Metabolomic profiling was performed using proton nuclear magnetic resonance (1H NMR). Placental explants exposed to 100 μg/mL of PS-MPs showed a significant increase in cytotoxicity over time (p < 0.01). Levels of mitochondrial and total superoxide anion (p < 0.01 and p < 0.05, respectively) and hydrogen peroxide (p < 0.001) were significantly elevated. PS-MP exposure resulted in a reduction in total sulfhydryl content (p < 0.05) and the activities of antioxidant enzymes superoxide dismutase (p < 0.01) and catalase (p < 0.05), while glutathione peroxidase activity increased (p < 0.05), and the oxidized/reduced glutathione ratio decreased (p < 0.05). Markers of oxidative damage, such as malondialdehyde and carbonylated proteins, also increased significantly (p < 0.001 and p < 0.01, respectively), confirming oxidative stress. Metabolomic analysis revealed significant differences between control and PS-MP-exposed groups, with reduced levels of alanine, formate, glutaric acid, and maltotriose after PS-MP exposure. This study demonstrates that high concentrations of PS-MPs induce time-dependent cytotoxicity, oxidative stress, and alterations in the TCA cycle, as well as in folate, amino acid, and energy metabolism. These findings highlight the need for further research to clarify the full impact of MP contamination on pregnancy and its implications for future generations.

Composition and Effects of Aerosol Particles Deposited on Urban Plant Leaves in Terrestrial and Aquatic Habitats.

Plants play a vital role in mitigating aerosol particles and improving air quality. This study investigated the composition characteristics and potential effects of particles retained on the leaf surfaces of two amphibious plants (i.e., Alternanthera philoxeroides and Hydrocotyle vulgaris) in both terrestrial and aquatic habitats. The results show that plant habitats influenced the composition of aerosol particles retained on leaf surfaces. Specifically, plants in terrestrial habitats retained a higher mass concentration of coarse and large particles rich in inorganic Ca2+, accounting for over 70% of total ions, whereas plants in aquatic habitats retained a greater abundance of fine and secondary particles with high fractions of water-soluble NO3- and SO42-, taking up over 65% of total anions. Secondary particles deposited on the surfaces of plants in aquatic habitats tend to deliquesce and transform from the particle phase to the liquid phase. Terrestrial habitats facilitate the deposition of large particles. Additionally, particle accumulation on leaf surfaces adversely affected the stomatal conductance of plant leaves, leading to reductions in both the transpiration and photosynthetic rates. This study provides insights into the impact and role of plants from different habitats in mitigating urban particulate pollution.

Chemical Spatiotemporal Characteristics and Environmental Driving Factors of Groundwater in Hetao Irrigation Area

To explore the chemical characteristics and environmental factors of groundwater in the Hetao Irrigation Area of Inner Mongolia, five irrigation fields, including UulanBuh, Jiefangzha, Yongji, Yichang, and Wulat, were selected as the research area. From 72 groundwater observation wells, a total of 216 groundwater samples were collected throughout three typical periods： the end of freeze-thaw （March）, the middle of irrigation （July）, and the end of autumn watering （November）. Comprehensive methods were utilized, such as statistical analysis, Piper three-line diagram, Gibbs diagram, ion ratio, and principal component analysis, to explore the changes in the groundwater chemical environment and the environmental driving factors of groundwater component formation. The groundwater drinking suitability was evaluated using the water quality index （WQI）, and the irrigation suitability was analyzed using the USSL and Wilcox plots. The results indicated that the groundwater in the research areas was generally saline, and the total anion and cation concentrations in each period in ascending order were as follows： late freeze-thaw stage, late autumn irrigation stage, and mid-irrigation stage, with Na+ and Cl- being the major contributing ions. The chemical type of groundwater was dominated by Cl-Na, followed by Cl·SO4-Ca·Mg and a coexistence with SO4-Ca·Mg, HCO3·Cl-Na, HCO3-Na, and HCO3-Ca·Mg. Based on WQI values, the shallow groundwater in Hetao Irrigation District was mainly classified as Class IV and Class V, and the quality was poor in general. According to the USSL diagram and Wilcox diagram, the comprehensive evaluation results showed that the salinity and sodium concentration of shallow groundwater in the irrigation area were generally high. A total of 80.6% of the water samples during the late freeze-thaw period, 76.1% during the mid-irrigation period, and 77.6% during the late autumn irrigation period lacked irrigation suitability. Two major controlling factors of groundwater chemical characteristics were present in the study area, namely, evaporation and rock weathering, and Na+ and Cl- mainly came from the dissolution and cation exchange of salt rocks. Agricultural irrigation and drought were the chief driving factors of groundwater chemical evolution in the Hetao Irrigation Area. The study provides technical support for optimizing agricultural management measures and a theoretical reference for rational utilization of groundwater resources in the Yellow River irrigation area of Inner Mongolia.

Gelsemium low doses protect against serum deprivation-induced stress on mitochondria in neuronal cells

Gelsemium dynamized dilutions (GDD) are known as a remedy for a wide range of behavioral and psychological symptoms of depression and anxiety at ultra-low doses, yet the underlying mechanisms of the mode of action of G. sempervirens itself are not well understood. The present study was designed to examine the neuroprotective effects of Gelsemium preparations in counteracting stress-related mitochondrial dysfunctions in neuronal cells. We started by studying how serum deprivation affects the mitochondrial functions of human neuroblastoma (SH-SY5Y) cells. Next, we looked into the potential of various Gelsemium dilutions to improve cell survival and ATP levels. After identifying the most effective dilutions, 3C and 5C, we tested their ability to protect SH-SY5Y cells from stress-induced mitochondrial deficits. We measured total and mitochondrial superoxide anion radicals using fluorescent dyes dihydroethidium (DHE) and the red mitochondrial superoxide indicator (MitoSOX). Additionally, we assessed total nitric oxide levels with 4,5-diaminofluorescein diacetate (DAF-2DA), examined the redox state using pRA305cells stably transfected with a plasmid encoding a redox-sensitive green fluorescent protein, and analyzed mitochondrial network morphology using an automated high-content analysis device, Cytation3. Furthermore, we investigated bioenergetics by measuring ATP production with a bioluminescence assay (ViaLighTM HT) and evaluated mitochondrial respiration (OCR) and glycolysis (ECAR) using the Seahorse Bioscience XF24 Analyzer. Finally, we determined cell survival using an MTT reduction assay. Our research indicates that Gelsemium dilutions (3C and 5C) exhibited neuroprotective effects by: - Normalizing total and mitochondrial superoxide anion radicals and total nitric oxide levels. - Regulating the mitochondrial redox environment and mitochondrial networks morphology. - Increasing ATP generation as well as OCR and ECAR levels, thereby reducing the viability loss induced by serum withdrawal stress. These findings highlight that dynamized Gelsemium preparations may have neuroprotective effects against stress-induced cellular changes in the brain by regulating mitochondrial functions, essential for the survival, plasticity, and function of neurons in depression.

High-accuracy quantitative model for phosphate anions in solution based on absorption spectroscopy and machine learning algorithms

The eutrophication pollution caused by excessive phosphorus seriously affects production and daily life of the people. Accurate and rapid detection of phosphate is crucial for water quality management and cleaner production. Currently, most analytical methods for phosphates involve the addition of multiple chemical reagents and are incapable of simultaneous quantification of total phosphorus (TP) and phosphate anions. The environmental friendliness and analytical performance of the methods need to be improved. Here, we established a green and high-accuracy quantitative model based on absorption spectroscopy and machine learning algorithms, which achieved the analysis of TP, H2PO4− and HPO42−. Based on the pH and absorption spectra of phosphate anions, classification and regression tree (CART), random forest (RF), and extreme gradient boosting (XGBoost) algorithms were used to train the original absorption spectra data, first-order derivative spectra data, and multiple feature parameter data of phosphate solutions with pH 4.7–10.0. By comparing the R2, root mean square error (RMSE) and mean absolute error (MAE) evaluation indicators, it was found that the phosphate anions quantitative model established using the CART based on the feature parameters of 187 nm performed the best, R2 > 0.9999, RMSE <3.4 × 10−6, MAE <8.1 × 10−7. The quantitative ranges of TP, H2PO4−, and HPO42− were 3.98 × 10−4—9.33 × 10−4 mol/L, 5.98 × 10−6—4.20 × 10−4 mol/L and 1.53 × 10−6—7.43 × 10−4 mol/L, respectively. Moreover, the quantitative model was optimized based on the spectral characteristics of 14 interfering ions, to improve the model analytical performance for unknown samples. The quantitative model developed in the study achieves accurate analysis of TP, H2PO4− and HPO42−, which is in line with green chemistry concept, and has the potential for prediction and early warning of water environment quality.

Investigation of radiogeology and environmental geochemistry of quarry ponds in post-tin mining areas of Phuket Island, southern Thailand

Increasing demand for water supply on Phuket Island for both the local consumption and hotel industry has led to overexploitation of ground- and surface water bodies; hence, it is unremittingly important to monitor the local hydrologic regime. Radiogeological and hydrogeochemical environments are investigated by representative water and surface sediment samples collected from the different quarry ponds located in post-tin mining areas on Phuket Island. The study assessed water quality, analyze the relationship between bedrock weathering and water quality, and identify radiogeological factors and natural radon concentrations, with insights into the local geology of the study areas. The representative quarry ponds of Phuket Island consist of a granite quarry pond (PKW1), a Quaternary sediment quarry pond (PKW2), a granitic-metamorphic quarry pond (PKW3), and the perturbation pond (PKW4), with the formation of a variety of geologic features. All collected water samples show total cation concentrations with Ca2+ > Na+ > K+ > Mg2+ and total anion concentrations with HCO3− > Cl− > NO3− > SO42−. However, Gibbs diagrams suggest that rock–water interactions and precipitation are major factors in geochemical processes controlling the water quality. Radon enrichments in the water samples are involved in the local geological structures and hydrogeological environments, as follows: PKW1 > PKW3 > PKW2 > PKW4. No significant correlation between the radon activity concentrations and major/minor ions is shown. Surface sediment samples are reported, and the activity concentrations of radium-228 and thorium-228 (radioactive decay series of thorium-232) are relatively higher than those of radium-226 (radioactive decay series of uranium-238). Therefore, the activity concentrations of natural radionuclides in the surface sediments could be directly influenced by physical weathering, particularly the depositional environments of granitic bedrock around the quarry ponds. Long-term monitoring is necessary to consider the behavior of quarry ponds, which is related to tourism planning and the overall development of Phuket Island.

Capillary electrophoresis using triple layer modified capillary facilitating salivary ion analyses: Application to search for potential stress markers induced by cold pressure test

In this study, we introduce a novel approach for the analysis of salivary ions using capillary electrophoresis (CE) with a triple-layer coated capillary. The capillary is sequentially coated with cationic silylating reagents, poly(vinylsulfonate), and polybrene to form a custom designed surface that effectively inhibits adsorption of protein matrix on the capillary inner wall and allows for reproducible ion analysis. For the CE with capacitively coupled contactless conductivity detection, we used suitable background electrolytes (BGEs) for salivary ion analysis. Anions were separated using a mixture of 2-(N-morpholino)ethanesulfonic acid and l-arginine, and cations were separated using that with 18-crown-6. This setup enabled rapid separation, within 4 min, together with sensitive detection. We quantified nine common anions and five cations typically found in saliva samples using this CE method, both before and after a cold pressure test (CPT, a standard stress test). The CE system demonstrated consistent ion separation across 30 consecutive measurements without requiring capillary replacement. Notably, the salivary ion balance remained predominantly anion-rich, regardless of the CPT. Cold water exposure induced greater variation in the total anion concentration than in the total cation concentration. Further analysis using multiple regression analysis revealed strong relationships between nitrate and nitrite, formate and phosphate, and potassium and nitrate, before and after the CPT. Notably, potassium and nitrate ions exhibited variations in response to stress. These results provided a method for assessing salivary ion composition and insights into the potential of salivary ions as biomarkers for stress.

River Sediments Downstream of Villages in a Karstic Watershed Exhibited Increased Numbers and Higher Diversity of Nontuberculous Mycobacteria

The impact of residential villages on the nontuberculous mycobacteria (NTM) in streams flowing through them has not been studied in detail. Water and sediments of streams are highly susceptible to anthropogenic inputs such as surface water flows. This study investigated the impact of seven residential villages in a karst watershed on the prevalence and species spectrum of NTM in water and sediments. Higher NTM species diversity (i.e., 19 out of 28 detected) was recorded downstream of the villages and wastewater treatment plants (WWTPs) compared to sampling sites upstream (i.e., 5). Significantly, higher Zn and lower silicon concentrations were detected in sediments inside the village and downstream of the WWTP’s effluents. Higher phosphorus concentration in sediment was downstream of WWTPs compared to other sampling sites. The effluent from the WWTPs had a substantial impact on water quality parameters with significant increases in total phosphorus, anions (Cl–and N-NH3–), and cations (Na+ and K+). The results provide insights into NTM numbers and species diversity distribution in a karst watershed and the impact of urban areas. Although in this report the focus is on the NTM, it is likely that other water and sediment microbes will be influenced as well.Graphical

Removal of Per- and Polyfluoroalkyl substances by anion exchange resins: Scale-up of rapid small-scale column test data

Anion exchange (IX) is a readily implementable water treatment method that can effectively remove per- and polyfluoroalkyl substances (PFAS). The overarching objective of this research was to predict PFAS removal in full- or pilot-scale packed-bed IX resin contactors from rapid small-scale column test (RSSCT) data. Specific objectives were to (1) assess the effects of IX resin crushing on total anion exchange capacity and packed bed density, (2) determine the effects of initial PFAS concentration on PFAS uptake capacity, (3) determine the rate-limiting step controlling PFAS uptake kinetics, (4) determine the effects of hydraulic loading rate on PFAS uptake capacity, and (5) link constant diffusivity RSSCT data to pilot test data to develop a scale-up protocol. Experiments were conducted with two single-use IX resins and three water matrices, including coagulated surface water and groundwater.Crushing IX resin did not substantially change the bed density and total anion exchange capacity, but the morphology of particles changed from almost perfectly spherical to irregularly shaped. PFAS uptake capacity was independent of influent PFAS concentrations in the 30–300 ng/L range. This finding facilitated the development of an RSSCT scale-up approach because influent PFAS concentrations in RSSCTs and corresponding pilot tests often differ. Biot number values and data from interrupted RSSCTs demonstrated that film diffusion or a combination of film diffusion and intraparticle diffusion controls the rate of PFAS uptake by IX resins. From RSSCTs with identical empty bed contact times but different hydraulic loading rates (vf), PFAS uptake capacity was found to be a function of the square root of the product of Sherwood number and particle shape factor (Sh×ϕ). Using a constant diffusivity RSSCT design with a reduced vf, full- or pilot-scale PFAS breakthrough data can therefore be predicted by multiplying the bed volumes of water treated in the RSSCT by a factor of (Shpilot×ϕpilot)/(ShRSSCT×ϕRSSCT) . This research will support the design of future IX treatment processes in the context of PFAS remediation and drinking water treatment.

The mitochondrial-related effect of the 905 nm photobiomodulation therapy on 50B11 sensory neurons.

Photobiomodulation therapy (PBMT) is known as a complementary tool to alleviate pain sensation in patients, nevertheless, there is still a gap of knowledge on its mechanism of action, thus limiting its clinical employment. In this study, a possible molecular mechanism of the 905 nm PBMT (0.25 W/cm2 ; 3, 6, 12, and 18 J/cm2 , 5 Hz) analgesic effect was tested on 50B11 cells, by investigating its impact on mitochondria. A decrement of adenosine triphosphate was detected, moreover, an increment of total reactive oxygen species and mitochondrial superoxide anion was found after PBMT with all protocols tested. PBMT at 18 J diminished the mitochondrial membrane potential, and influenced mitochondrial respiration, decreasing the oxygen consumption rate. Finally, a decrement of extracellular signal-regulated kinase 1/2 phosphorylation was observed with the protocol using 12 J. Taken together these findings highlighted the intracellular effects, mainly correlated to mitochondrial, induced by 905 nm PBMT in sensory neurons, indicating the central role of this organelle in the cellular response to 905 nm near-infrared laser light.

Hydrochemical Characteristics and Human Health Risk Assessment of Surface Water in the Danjiang River Source Basin of the Middle Route of China’s South-to-North Water Transfer Project

The Danjiang River basin is an important water source for the Middle Route of the South-to-North Water Diversion Project. With the shortage of water resources and the increase in pollution pressure, it is of great significance to study the hydrochemical characteristics of surface water in the Danjiang River basin and the risk to human health posed by polluted water bodies for the protection and utilization of water resources. In this paper, 40 surface water samples were collected and analyzed by innovatively adopting the sampling principle of “geological structure unit + landform unit + small watershed unit”. Comprehensive mathematical statistical analysis, Piper trilinear diagrams, Gibbs diagrams, and ion ratio coefficients were used to analyze the hydrochemical composition, spatial distribution characteristics and influencing factors of surface water in the Danjiang River. The entropy weight comprehensive index method (EWQI) and the health risk assessment model recommended by the United States Environmental Protection Agency (HHRA model) were used to evaluate the water quality and potential non-carcinogenic risk of surface water in the Danjiang River source basin. The results showed that the pH of surface water in the study area was 7.02~8.77, with an average value of 8.26; and the TDS was ranged from 134 to 388 mg/L, with an average value of 252.75 mg/L. The main cations in the surface water were Ca2+ and Mg2+, accounting for 71% and 20% of the total cations, respectively, while the main anions were HCO3− and SO42−, accounting for 74% and 19% of the total anions, respectively. The hydrochemical type was HCO3− Ca·Mg. The hydrochemical genesis was mainly controlled by the weathering of carbonate rocks, while some ions were influenced by the weathering of silicate rocks, and human activities were also an important factor affecting the chemical characteristics of the water. The EWQI of surface water in the whole region was 8.95~25.69, and the health risk index (HI) of nitrate pollution ranged from 0.0122 to 0.2118, in which the HI ranges for children and adults were 0.0217~0.2118 and 0.0122~0.1333, respectively, indicating that the water quality of the entire study area met the Class I water standards, and the potential non-carcinogenic risk of nitrate was low. However, its impact on children was significantly higher than on adults, so it is recommended to monitor the water quality downstream of urban areas in the study area to reduce agricultural non-point source pollution and urban domestic sewage discharge and thereby reduce the potential health risks for young populations.

Oxidative assessment of thawed donkey semen with seminal plasma, permeable and non-permeable cryoprotectants

During cryopreservation, donkey semen is exposed to oxidative and osmotic damage that alters the plasma membrane and causes alteration of sperm metabolism. In equids, the elimination of seminal plasma (SP) is a necessary process for the conservation of sperm in artificial conditions such as freezing, however, it is known that SP has an important role in physiological processes for sperm functions such as protection, transport, antioxidant defense, regulation of the inflammatory response in the uterus and interaction with the oocyte. The objective of this study was to evaluate total antioxidant capacity (TAC), reactive oxygen species (ROS) production and mitochondrial membrane potential of sperm, with different alternatives for donkey semen cryopreservation with permeable, non-permeable cryoprotectants and SP. Samples of semen were collected from ten Colombian Creole donkeys (Equus asinus), three ejaculates were collected from each donkey, for a total of 30 ejaculates. Eight treatments (T) were used with different combinations of 5% of dimethylformamide (DMF), 200 mM of sucrose (SUC), 1% of bovine serum albumin (BSA) and 10% of homologous seminal plasma (SP), as following: T1: DMF, T2: DMF/SP, T3: SAC/BSA, T4: SAC/BSA/SP, T5: DMF/SAC/BSA, T6: DMF/SAC/BSA/SP, T7: DMF/BSA, T8: DMF/BSA/SP. Besides the treatment, sperm was extended in EquiPlus® and 5% of clarified egg yolk, until a sperm concentration of 100 × 106 spermatozoa/mL. Posthawing, TAC was evaluated by the cationic radicalmethod (ABTS) and by the method of oxygen trapping capacity (ORAC) methodologies, total reactive oxygen species (ROS) production, superoxide anion (O2-) and hydroxyl radical (OH-) content were evaluated by spectrofluorimetry; sperm viability and mitochondrial membrane potential (ΔΨM) were measured by flow cytometry. For statistical analysis, a general linear model was fitted for each dependent variable. Normal distribution of variables was validated with the Kolmogorov–Smirnov test. Means were compared by the Tukey's test. Treatments T3 and T4 presented higher TAC (p<0.05) (ABTS and ORAC) compared to T1. For ΔψM, the lowest mean value was 9.1% for T4 (p<0.05), corresponding to one of the treatments without permeable cryoprotectant and SP. For sperm viability, the lowest values were found in both treatments with non-permeable cryoprotectant. Moreover, the treatments that were supplemented with SP showed higher production of ROS (p<0.05). In conclusion, supplementation of donkey semen with seminal plasma for cryopreservation does not alter the total antioxidant capacity; additionally, freezing semen with non-permeable cryoprotectants generates low sperm viability, low mitochondrial membrane potential and a high amount of reactive oxygen species and the composition of the freezing extender for donkey semen with seminal plasma influences the generation of total reactive oxygen species.

Soil Nutrient, Salinity, and Alkalinity Responses of Dendrocalamopsis oldhami in High-Latitude Greenhouses Depending on Planting Year and Nitrogen Application

This study explored the viability of greenhouse cultivation of Dendrocalamopsis oldhami under the “South Bamboo North Transplanting” initiative. In this study, the effects of planting year and nitrogen application on changes in soil nutrient levels, salinity, and alkalinity over the plant growth period were explored. After the introduction and planting of bamboo in 2017, a soil layer with a thickness of 0–40 cm was sampled at the end of the shooting stage in the greenhouse between 2017 and 2019 (late August), and the bamboo shoot yield and standing culm density were measured. Following the application of nitrogen to the bamboo groves in 2019, three nitrogen levels were established: no nitrogen (N1:0 g grove−1), medium nitrogen (N2:540 g grove−1), and high nitrogen (N3:1080 g grove−1). Soil layers at depths of 0–20 and 20–40 cm were sampled during the shoot elongation stage (late May) and at the end of the shooting stage (late August). The yield and nutrient content of bamboo shoots under different nitrogen treatments were also investigated. The results showed that Ca2+ and HCO3− were the main salt ions in greenhouse soil. With later planting years, the total number of cations (Ca2+, Na+, Mg2+, and K+) decreased, whereas the total number of anions (HCO3−, SO42−, NO3−, and Cl−) increased, resulting in a decrease in the percentage of exchangeable sodium (ESP), pH, and electrical conductivity (EC). The diameter at breast height, individual weight, and quantity of bamboo shoots increased annually, and the standing culm density increased by 1.4 times. Each year, the total nitrogen content decreased, whereas the alkali-hydrolyzed nitrogen, available phosphorus, and available potassium contents increased. Nitrogen application resulted in a significant decrease in ESP and pH and an increase in the total anion, cation, and EC values. It also reduced soil organic carbon, total nitrogen, total phosphorus, total potassium, available phosphorus, and available potassium. Nitrogen application increased the number of bamboo shoots, total yield, and accumulation of N and P; however, there was no significant difference between N2 and N3. In conclusion, the salinization of calcareous soil was alleviated, and the available nutrients were activated following the introduction of D. oldhami from south to north. The mineralization rates of organic matter and soil fertility increased. Soil acidification and EC decreased at the end of the shoot stage. Nitrogen application acidified the soil, and the yield and soil salt accumulation increased with increasing nitrogen levels. The nutrient uptake efficiencies of nutrients at high nitrogen levels were lower than those at medium nitrogen levels. Therefore, soil salt concentrations with values 0.26 &lt; EC &lt; 0.42 hindered the nutrient uptake of D. oldhami.

Potential functional differentiation from microbial perspective under dryland-paddy conversion in black soils

Improving soil carbon sequestration and reducing greenhouse gas emissions in farmland require understanding how the microbial communities that control the agroecosystem function. Here, we surveyed the soil microbial communities in neighboring pairs of dryland and paddy fields in the black soils of northeastern China. Soil moisture, mean weight diameter of aggregates, fluorescence index and biological index of dissolvable organic matter, total anion concentration, and prokaryotic community α-diversity were higher in paddy soils than in dryland soils, while soil saturated hydraulic conductivity (SHC), dissolvable total nitrogen, and fungal community α-diversity were lower in paddy soils than in dryland soils. Moreover, soil moisture (P < 0.01) and SHC (P < 0.05) had significantly positive correlations with the α-diversity of prokaryotic and fungal communities, respectively. The co-occurrence network complexity of microbial communities was lower in paddy fields than in dryland fields, while the co-occurrence network tightness and cooperation of microbial communities were higher in paddy fields than in dryland fields, which may help paddy microbiome resist environmental disturbances. Taken together, both dryland and paddy fields had their own advantages in evaluating soil biological health from microbial community diversity and network stability. Additionally, the differential groups of CH4 production, S cycle, and Fe cycle (e.g., Bathyarchaeota, Bacteroidetes, and Geobacter) increased, while those of environmental remediation and biological control (e.g., Blastococcus and Roseiflexus) decreased after the change from dryland to paddy fields. Further combined with metagenomic analysis, the functions of CH4 production, CO2 fixation, N fixation, and sulfur reduction were enhanced in paddy soils, while those of CH4 oxidation, nitrification, and N2O production were reduced. In conclusion, the ecological functioning of the differential groups may lead to the increase of CH4 emission and CO2 fixation, and the decrease of N2O emission in paddy fields of black soil, even in non-flooding period.

Variation characteristics of acid rain in Zhuzhou, Central China over the period 2011-2020

Zhuzhou was one of the most polluted cities in China with the serious acid rain. Due to the implementation of air pollution control measures from 2016 to 2018, the acid rain pollution in this city has reduced. In order to understand the recent situation, a comprehensive study on the acid rain was carried out from January 2011 to December 2020. The pH values during the study period varied from 3.3 to 7.5, with a volume-weighted mean value of 4.7. The predominant acidic components of the precipitation were SO42− and NO3−, accounting for 89.3% of the total anions. The ratio of non-sea-salt SO42− to NO3− showed a decreasing trend, revealing that the pollution type of acid rain changed from sulfuric acid type to sulfuric acid and nitric acid compound type. The correlation analysis (p < 0.05) showed that SO42− was positively correlated with NH4+, Ca2+, and Mg2+; hence, it predominated in precipitation as (NH4)2SO4, NH4HSO4, CaSO4, and MgSO4. Significant positive correlation of Ca2+ with Mg2+ shows that they may originated mainly from crust. Significant positive correlation between SO42− and F− and Cl− indicate that their source may be related to the non-ferrous metal smelting industry in Zhuzhou. Further correlation analysis shows that emissions from the non-ferrous metal smelting industry in the area have a large significant on SO42− and F− in precipitation, while Cl− may still be emitted from other anthropogenic sources.

Blood Gas, Acid-Base and Electrolyte Analysis in Healthy Dromedary Camel Calves up to 21 Days of Life.

The importance of prompt evaluation and care of the newborn is essential for reducing neonatal mortality, which represents a major cause of loss in camelids. This study investigated the blood gases, acid-base and electrolyte profiles in healthy dromedary calves during the first 3 weeks of life, assessing possible associations with age. Twenty-one dromedary camel calves aged 1 to 21 days were sampled, and venous whole blood analyzed through a VETSTAT® analyzer. The following parameters were measured: sodium (Na+), potassium (K+), chloride (Cl-), hydrogen ion concentration (pH), partial pressure carbon dioxide (pCO2), partial pressure oxygen (pO2), total hemoglobin concentration (tHb), hemoglobin oxygen saturation (sO2), total carbon dioxide (tCO2), bicarbonate (HCO3-), base excess (BE) and anion gap (AG). Calves were divided in two groups; younger calves (1-10 d), and older calves (11-21 d). Statistical analysis showed an effect of age, with lower K+ (p < 0.001) and higher Na+ and Cl- (p < 0.05) mean concentrations in the younger calves compared to the older ones, and higher pCO2 and lower sO2 mean concentrations in the older group. These preliminary results firstly described the blood gas, acid-base and electrolyte profiles in the healthy dromedary calf during the first 3 weeks of age, suggesting an effect of age on some parameters.

Hydrochemical Characteristics and Ion Source Analysis of the Yarlung Tsangpo River Basin

In order to investigate the hydrochemical characteristics and their controlling factors, 212 water samples from the Yarlung Tsangpo River and its tributaries were collected over three precipitation periods in 2018 and analyzed using mathematical statistics, the Gibbs and ion ratio methods, and principal component analysis. The results showed the following: (1) The cations in the water were mainly Ca2+, Na+ and Mg2+, and the anions HCO3− and SO42− were predominant, accounting for more than 97% of the total anion concentrations. The concentration of total dissolved solids (TDS) was 204.51 mg/L. The water chemistry type was SO4·(HCO3)−Ca·(Mg) water. (2) The concentrations of major ions in the Yarlung Tsangpo River fluctuate, but in general, the vast majority of the major ions in the water follow the trend of both first increasing and then decreasing in the three precipitation periods. The hydrochemical features of the Yarlung Tsangpo Basin have seasonal differences. (3) The Gibbs model and the PCA analyses showed that the Yarlung Tsangpo River water chemical components are mainly affected by rock weathering. In addition, the influence of the mining industry also plays an important role. The heavy metal concentrations in the three precipitation periods of the Yarlung Tsangpo River could reach the standard of first-class surface water quality.

Comparative Analysis of Bioactive Components of Enzymatically and Fermentatively Produced Fish Sauce from Sardine

Fish sauce, a flavored condiment produced by traditional fermentation of low-value fish. The time of fermentation and biochemical safety of sauce are the major concern in traditional fermentation. The enzymatic and fermentative methods were employed to produce Sardine (Sardinella longiceps) sauce under optimized conditions using response surface method. Salt (20%, w/w) and papain (3%, w/w) were used for enzymatic production; while, salt (25%, w/w), sugar (7.5%, w/w) and lactic culture (10%, w/v; Pediococcus pentosaceus FSBP4-40) were employed in fermentative production. Significant change in bioactive components such as pH, non-enzymatic browning, non-protein nitrogen, degree of hydrolysis, titratable acidity, total soluble nitrogen, and total volatile base nitrogen was observed in treated samples compared to the control. Total antioxidant activity (as ascorbic acid, μg/ml), percent DPPH, ABTS, and superoxide anion scavenging activities of fermented sauce were higher at 3976±90, 53.11±0.5, 99.6±0.3, 67.7±0.5 respectively; as compared to enzyme-treated samples which showed 952±70, 31.46±0.5, 76.5±1.0, 61.8±1.4 for the respective parameters, after 180 days storage. Reducing potential was found significantly higher (P&lt;0.05) in treated sauces compared to the control and fatty acid profile showed different changes. The study emphasizes the role of accelerating fermentation, either enzymatically or fermentatively, to produce biochemically and biofunctional superior Sardine sauce.

SOURCE IDENTIFICATION AND VARIATION IN THE CHEMICAL COMPOSITION OF RAINWATER IN THE COASTAL AND INDUSTRIAL AREAS: A CASE STUDY OF IKOT ABASI, SOUTH-EASTERN NIGERIA

Studies on precipitation Chemistry were carried out with the aim to understand the nature and sources of rainwater at Utaewa (Location 1), a coastal village and Ikpetim, near Ibom Power Station (Location 2), all in Ikot Abasi Local Government Area, southern, Nigeria. These locations respectively represent the coastal and industrial regions. The rainwater samples, collected at these locations, were analyzed for major cations, anions, electrical conductivity and pH with the aim of identification of variation in the physiochemical compositions of the rainwater samples. The analysis of the rainwater samples gave a pH at locations 1 and 2 as 5.62 ± 0.26 and 5.77± 0.25 respectively during the wet season, while the pH of the rainwater at locations 1 and 2 during dry season were 5.41 ± 0.14 and 5.84 ± 0.21 respectively. The pH values indicated acidic water and were below the World Health Organisation (WHO) Standard of 6.5 to 8.5, but close to the World Meteorological Organisation (WMO) optimum pH value of 5.6 for rainwater from unpolluted continental areas. The predominance of 𝐶𝑙−and𝑁𝑎+ were observed in the coastal environment whereas, calcium, sulphate, nitrate and ammonium ions predominate in industrial environment where there are power generating plants, Aluminium smelting company and gas station. The total anion (37.9%) at Utaewa is less influenced by anthropogenic activities whereas total anion (72.5%) at Ikpetim, near Power Plant is influenced by pollutants emitted by anthropogenic activities. The ratio:𝐻+/(NO3- + SO42-) was observed as 0.04 and 0.008 for Utaewa and Ikpetim respectively, which are close to zero, indicating that 99 % of acidity in the rainwater is neutralized in the study area with no consequence of acidity impact on the soil, surface waters and groundwater in the study area. Ca2+ , K+ and Na+ play important roles in neutralization of acidic ions in rainwater. For source identification, correlation matrix analysis was established, which showed that at locations 1 and 2,strong correlation exists between the acidic ions SO42- and NO3-, indicating their origin from anthropogenic activities. This is viewed to be attributed to the similarity in their behaviour in precipitation and the co-emissions of their precursors, which are SO2 and NO2. The major ion enrichment factors (EF) followed the order at location 1 during the dry season;𝐶𝑎2+𝑁𝑎+⁄ (8.58) &gt;𝐾+𝑁𝑎+⁄ (4.32) &gt;𝑆𝑂42−𝑁𝑎+⁄ (0.68) &gt;𝐶𝑙−𝑁𝑎+⁄ (0.11), while the enrichment factor (EF ) during the wet season at location 1 followed the order , 𝐶𝑎2+𝑁𝑎+⁄ (11.92 )&gt;𝐾+𝑁𝑎+⁄ (3.78) &gt;𝑆𝑂42−𝑁𝑎+⁄ (0.88) &gt;𝐶𝑙−𝑁𝑎+⁄ (0.11).

Impacts of Melatonin on Functionalities of Constructed Wetlands for Wastewater Treatment

Constructed wetlands (CWs) are effective wastewater treatment systems, relying on plant and substrate uptake and microbial depletion to remove pollutants. It has been reported that melatonin can promote plant growth and change the structure of microbial communities. The effects of melatonin on stress tolerance of plants have been extensively studied, while the effects of melatonin on the efficiency of wastewater treatment in constructed wetlands are rarely known. In the current study, 1 mM melatonin was added to the constructed wetland systems to determine physiological characteristics of Phragmites australis, microbial enzyme activity, and microbial community structure of CWs. Under melatonin treatment, the An and gs of Phragmites australis plants were significantly improved compared with the control. In addition, the contents of phosphate and total anion in the xylem sap of Phragmites australis significantly increased. However, the concentration of total phosphorus in the effluent did change significantly. Melatonin treatment improved the dehydrogenase activity and significantly improved the removal efficiency of NH4+-N in CWs. Furthermore, melatonin reduced the richness of the microbial community in CWs, while it increased the diversity of bacterial community and altered microbial composition. FARPROTAX analysis showed that melatonin increased the abundance of bacteria involved in nitrogen fixation and ureolysis, which may be related to the improvement of plant photosynthetic performance and improved rhizosphere oxygen environment. These results suggested that melatonin may affect plant performance and microbial composition and functions to improve the purification effect of constructed wetland.