Increase In Na Research Articles

Thermophysical Insights into the Anti-Inflammatory Potential of Magnetic Fields

Background: Inflammation is caused by an excess of Sodium ions inside the cell. This generates a variation in the cell’s membrane electric potential, becoming a steady state from a thermodynamic viewpoint. Methods: This paper introduces a thermodynamic approach to inflammation based on the fundamental role of the electric potential of the cell membrane, introducing an analysis of the effect of heat transfer related to the inflammation condition. Results: The direct proportionality between the reduction in temperature and the increase of Na+ outflow may ameliorate the inflammation cascade. Conclusions: Based on these ion fluxes, we suggest the consideration of a ‘companion’ electromagnetic therapeutic wave concept in support of the present anti-inflammatory treatment.

The Utilization of Vegetable Powders for Bread Enrichment—The Effect on the Content of Selected Minerals, Total Phenolic and Flavonoid Content, and the Coverage of Daily Requirements in the Human Diet

The aim of this study was to evaluate the content of selected minerals and total phenolic and flavonoid content of wheat bread and bread enriched with varying amounts of carrot powder (CP) and pumpkin powder (PP). In addition, the coverage of daily requirements of selected minerals was evaluated after the consumption of 100 g of each type of bread. The research included seven types of bread: wheat bread (WB) and bread enriched with 10%, 20%, and 30% CP and PP. The vegetable powders were obtained by freeze-drying. The concentrations of minerals—sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn)—were determined by atomic absorption spectroscopy (AAS) method. Coverage of daily requirements after consumption of a serving of bread was determined based on Recommended Daily Allowance (RDA) and Adequate Intake (AI) ratios for minerals, according to the nutritional standards for the Polish population. The addition of 10% PP led to a greater increase in Na, K, Mg, and Cu in the bread compared to CP, while for Ca, Fe, Zn, and Mn a greater increase was observed with the addition of 10% CP than PP. Among macronutrients, the greatest changes in content were recorded for Ca—the addition of 10 and 20% CP and PP resulted in increases of 66, 113, 51 and 59%. Among micronutrients, the addition of CP and PP to wheat bread caused the largest changes in Cu (46–150% increase) and Mn (25–99% increase) content. Additionally, there was a tenfold increase in total phenolic content (TPC) when 30% CP was added to the bread. Consuming 100 g of bread with CP and PP provided the greatest coverage of K (41–60%), Cu (8–17.5%), and Mn (6–17%). These findings suggest that fortification of bread with vegetable powders has the potential to be a useful method of enriching the mineral composition and increasing the proportion of selected minerals in the human diet.

Age-related increase in the excitability of mouse layer V pyramidal neurons in the primary motor cortex is accompanied by an increased persistent inward current.

Sarcopenia, or pathological age-related loss of muscle strength and mass, contributes to physical function impairment in older adults. While current understanding of sarcopenia is centered mostly on neuromuscular mechanisms, mounting evidence supports that deficits at the level of the primary motor cortex (PMC) play a significant role. Despite the importance of the PMC to initiate movement, understanding of how age affects the excitability of layer V pyramidal neurons (LVPNs) of the PMC is limited. To address this, we used the whole-cell patch clamp technique to measure the excitability of LVPNs of the PMC in young, late adulthood, and old mice. Old LVPNs had increased firing frequency and membrane input resistance, but no differences in action potential kinetics versus young and late adulthood mice. Since changes in the persistent inward current (PIC) are known to contribute to changes in motor neuron excitability, we measured LVPN PICs as a putative contributor to LVPN excitability. The PIC amplitude was increased in old LVPN via increases in Na+ and Ca2+ PICs, in addition to being active across a wider voltage range. Given that LVPN function is integral to initiation of voluntary muscle contraction, altered LVPN excitability likely contributes to age-related impairment of physical function.

Enhancing selective NH4+ recovery from wastewater using modified zeolite-based flow electrode capacitive deionization

Despite flow-electrode capacitive deionization (FCDI) is an emerging technology for desalination, contaminant removal, and resource recovery, the application of conventional FCDI in wastewater treatment is hindered by the electrode selectivity and material costs. In this study, we synthesized a low-cost ammonium (NH4+) adsorption electrode material by modifying zeolite using ethylenediaminetetraacetic acid disodium salt (EDTA-2Na). The flow electrode prepared by the mixture of EDTA-zeolite and carbon black exhibits a high selectivity and adsorption capacity for the recovery of NH4+ from wastewater. The NH4+ in wastewater passes through the ion exchange membrane and is rapidly adsorbed by the modified zeolite through ion exchange, while Na+ is retained in the electrolyte. The decrease in NH4+ concentration and the increase in Na+ concentration in the catholyte lead to a significant change in ion concentration gradient across the membrane. Consequently, the transmembrane selectivity between NH4+ and Na+ reached 3.46. We validated the feasibility of NH4+ recovery using FCDI with food waste fermentation supernatant. Under optimal operating conditions, 99.15 % of the NH4+ in the fermentation supernatant was removed, and 95.92 % of the NH4+ in the electrolyte was stored in the EDTA-zeolite. By gravitational settling, the NH4+-rich modified zeolite was separated from carbon black and could be utilized as nitrogen fertilizer. Meanwhile, the mixture of carbon black and brine was used to prepare a fresh electrode suspension. In brief, the FCDI system exhibits a satisfying NH4+ recovery performance and demonstrates a sustainable wastewater resource recovery strategy.

Water quality and dissolved load in the Chirchik and Akhangaran river basins (Uzbekistan, Central Asia)

Uzbekistan (Central Asia) is experiencing serious water stress as a consequence of altered climate regime, past over-exploitation, and dependence from neighboring countries for water supply. The Chirchik–Akhangaran drainage basin, in the Tashkent province of Uzbekistan, includes watersheds from the Middle Tien Shan Mountains escarpments and the downstream floodplain of the Chirchik and Akhangaran rivers, major tributaries of the Syrdarya river. Water in the Chirchik–Akhangaran basin is facing potential anthropogenic pressure from different sources at the scale of river reaches, from both industrial and agricultural activities. In this study, the major and trace element chemistry of surface water and groundwater from the Chirchik–Akhangaran basin were investigated, with the aim of addressing the geogenic and anthropogenic contributions to the dissolved load. The results indicate that the geochemistry of water from the upstream catchments reflects the weathering of exposed lithologies. A significant increase in Na+, K+, SO42−, Cl−, and NO3− was observed downstream, indicating loadings from fertilizers used in croplands. However, quality parameters suggest that waters are generally suitable for irrigation purposes, even if the total dissolved solid indicates a possible salinity hazard. The concentration of trace elements (including potentially toxic elements) was lower than the thresholds set for water quality by different regulations. However, an exceedingly high concentration of Zn, Mo, Sb, Pb, Ni, U, As, and B compared with the average river water worldwide was observed. Water in a coal fly-ash large pond related to the Angren coal-fired power plants stands out for the high As, Al, B, Mo, and Sb concentration, having a groundwater contamination potential during infiltration. Spring waters used for drinking purposes meet the World Health Organization and the Republic of Uzbekistan quality standards. However, a surveillance of such drinking-water supplies is suggested. The obtained results are indicators for an improved water resource management.

On the sensitivity of aerosol–cloud interactions to changes in sea surface temperature in radiative–convective equilibrium

Abstract. Clouds play a vital role in regulating Earth's energy balance and are impacted by anthropogenic aerosol concentration (Na) and sea surface temperature (SST) alterations. Traditionally, these factors, aerosols and SST, are investigated independently. This study employs cloud-resolving, radiative–convective-equilibrium (RCE) simulations to explore aerosol–cloud interactions (ACIs) under varying SSTs. ACIs are found to be SST-dependent even under RCE conditions. Notably, changes in cloud radiative effects for both longwave radiation and shortwave radiation lead to a decrease in top-of-atmosphere (TOA) energy gain with increasing Na. The changes in TOA shortwave flux exhibit greater sensitivity to underlying SST conditions compared to longwave radiation. To comprehend these trends, we perform a linear decomposition, analyzing the responses of different cloud regimes and contributions from changes in the cloud's opacity and occurrence. This breakdown reveals that ice and shallow clouds predominantly contribute to the radiative effect, mostly due to changes in the cloud's opacity and due to the Twomey effect, which is proportional to the baseline cloud fraction. Moreover, with an increase in Na, we observe an increase in latent heat release at the upper troposphere associated with heightened production of snow and graupel. We show that this trend, consistently across all SSTs, affects the anvil cloud cover by affecting the static stability at the upper troposphere via a similar mechanism to the stability iris effect, resulting in an increase in outgoing longwave radiation. In conclusion, under the ongoing climate change, studying the sensitivity of clouds to aerosols and SST should be conducted concomitantly as mutual effects are expected.

Microstructure evolution, dielectric properties, and nonlinear response of Na+-doped CdCu3Ti4O12 ceramics.

In this study, Cd1-x Na x Cu3Ti4O12 (x = 0, 0.02, 0.04, 0.06, and 0.08) ceramics were prepared via a solid-state method. The phase composition, microstructure, and defect characteristics as well as optical, dielectric, and nonlinear properties of the ceramics were systematically studied. A CuO second phase was detected in doped samples. Grain boundary precipitates, Na with a low melting point, and oxygen and cation vacancies together caused the grain size to first increase and then decrease with an increase in the Na+ doping amount. The abundant emerging cation vacancies with an increase in Na+ content led to a decrease in the optical energy band. The sample with x = 0.04 exhibited the highest ε' value (∼35 800) due to its largest grain size. Moreover, it possessed a lower tan δ (∼0.053) at 10 kHz, which was attributed to the multiplication of insulating grain boundaries. The huge dielectric constant originated from Maxwell-Wagner polarization at low frequencies and followed the internal barrier effect model. The lowest tan δ (∼0.037) and optimal nonlinear properties (α = 3.66 and E b = 3.82 kV cm-1) were obtained in the sample with x = 0.08, which were associated with its highest grain boundary resistance and barrier height. Electric modulus data proved that dielectric relaxation at low frequencies was associated with grain boundaries. Dielectric anomalies in the high temperature range were attributed to oxygen vacancies.

Independent variables of pH: Ten Knights of the Hydrogen Ion Kingdom-Part I. A prospective observational study.

CO2, HCO3, SID, and total weak acids have been defined as pH's independent variables. However, according to Gamble, HCO3 should be equal to the difference between the sum of cations and the sum of anions besides HCO3. Therefore, if this mathematical expression is substituted for HCO3 in the Henderson-Hasselbalch equation, all independent variables of pH can be demonstrated. Our aim is to test this theory in this study. This prospective observational study was conducted between 2019 and 2020. All admitted patients to the intensive care unit who were >18 years old were included. Demographic data, blood gas parameters, albumin, magnesium, and inorganic phosphorus levels, and outcomes were recorded twice (at admission and at the 24th hour). The multivariate linear regression model was used to determine pH's independent variables. In the multivariate linear regression model, pH was significantly increased by each unit increase in Na, K, Ca, and Mg (mmol L-1). In contrast, pH was significantly decreased by each unit increase in CO2, Cl, lactate, albumin (g dL-1), inorganic phosphorus (mg dL-1), and the strong ion gap. Ten independent variables can accurately predict the changes in pH. For this reason, all ten independent variables should be separately evaluated when interpreting the acid-base status. With this understanding, all algorithms regarding acid-base evaluation may become unnecessary.

Cellulose-Encapsulated Composite Electrolyte Design: Toward Chemically and Mechanically Enhanced Solid-Sodium Batteries.

Sulfide- and halide-based ceramic ionic conductors exhibit comparable ionic conductivity with liquid electrolytes and are candidates for high-energy- and high-power-density all-solid-state batteries. These materials, however, are inherently brittle, making them unfavorable for applications. Here, we report a mechanically enhanced composite Na+ conductor that contains 92.5 wt % of sodium thioantimonate (Na3SbS4, NSS) and 7.5 wt % of sodium carboxymethyl cellulose (CMC); the latter serves as the binder and an electrochemically inert encapsulation layer. The ceramic and binder constituents were integrated at the particle level, providing ceramic NSS-level Na+ conductivity in the NSS-CMC composite. The more than 5-fold decrease of electrolyte thickness obtained in NSS-CMC composite provided a 5-fold increase in Na+ conductance compared to NSS ceramic pellets. As a result of the CMC encapsulation, this NSS-CMC composite shows increased moisture resistivity and electrochemical stability, which significantly promotes the cycling performance of NSS-based solid-state batteries. This work demonstrates a well-controlled, orthogonal process of ceramic-rich, composite electrolyte processing: independent streams for ceramic particle formation along with binder encapsulation in a solvent-assisted environment. This work also provides insights into the interplay among the solvent, the polymeric binder, and the ceramic particles in composite electrolyte synthesis and implies the critical importance of identifying the appropriate solvent/binder system for precise control of this complicated process.

Physiological and Cellular Ultrastructural Responses of Isatis indigotica Fort. under Salt Stress

This study aimed to analyze the effects of salt stress on the growth physiology and plant-cell ultrastructure of Isatis indigotica Fort. (I. indigotica) to evaluate its adaptability under salt stress. The effects of different concentrations of salt (NaCl; 0, 25, and 300 mmol·L−1) on the agronomic traits, activities of related enzymes, ion balance, and mesophyll-cell ultrastructure of I. indigotica were studied in a controlled pot experiment. Results showed that compared with those of the control group, the aerial-part fresh weight, underground fresh weight, tiller number, root length, root diameter, plant height, and leaf area of salt-stressed I. indigotica increased at 25 mmol·L−1 and then decreased at 300 mmol·L−1. The changes in levels of superoxide dismutase, peroxidase, ascorbate peroxidase, and catalase showed a similar trend, with significant differences compared with control group. Salt stress altered the ion balance of I. indigotica, resulting in a significant increase in Na+ content and a significant decrease in K+ content. The contents of Ca2+ and Mg2+ changed to varying degrees. The analysis of the microstructure of the root showed that under salt treatment, the epidermal cells of the root significantly thickened and the diameter of the xylem decreased. The results of ultrastructural analysis of mesophylls showed that salt stress can cause cell-membrane contraction, cell-gap enlargement, disorder in the structures of chloroplasts and mitochondria, and an increase in the number of osmiophilic particles. These changes were aggravated by the increase in NaCl concentration. This study reveals the response of I. indigotica to salt stress and provides a basis for further study on the salt-tolerance mechanism of I. indigotica.

The effect of using jug-type water filters on selected metals concentration in tap water – a case study

ABSTRACT In this study, the effect of the filtration process on Na, K, Mg, Ca, Fe and Zn concentration in water, using filters from one of the leading European manufacturers, was investigated. The increase in Na (up to 300%) and K concentration (up to 320%) at the beginning of jug filter usage was reported. A decrease in Ca, Fe and Zn concentration was observed. Standard filters remove 80–90% of Mg from tap water at the beginning of the usage, while magnesium-enriching ones slightly increase its concentration – from around 8 to 12–25 mg/L. Significant changes in the filter's operating characteristics were also observed for other studied elements as they wore out. Using Mg-enriching filters can increase magnesium intake from 4–5 to 6–15% of the recommended daily dose from water consumption. The results were also discussed regarding the amounts of macroelements found in commercially available bottled water. The magnesium concentration in tap water after filtration through magnesium-enriching filters was lower compared to bottled mineral waters. The authors note a scope for the development of water filter production technology, in particular, the need to develop filters that more efficiently enrich water with magnesium and do not increase sodium concentration.

Age and composition of perovskite in ultramafic lamprophyres from the Zima alkaline-ultramafic carbonatite complex, the southern margin of the Siberian craton: Petrogenetic implications

This paper presents data on the age and trace element composition of perovskites from dykes of ultramafic lamprophyres (aillikites) of the Zima alkaline-ultramafic carbonatite complex (Bolshaya Tagna and Bushkanay) located within the Urik-Iya graben, Eastern Sayan region, southern margin of the Siberian craton. The studied samples exhibit similar textural and structural features but differ slightly in the mineral composition of the groundmass. They have a porphyritic structure, a massive texture, and consist of olivine macrocrystals embedded in a fully crystallized groundmass composed of perovskite, apatite, spinel, phlogopite, garnet, carbonates, clinopyroxene and other minerals. The macrocrystals quantity varies between 40 and 50 vol%. With the exception of a single sample from the Bushkanay dyke, olivine is entirely replaced by serpentine and/or talc.Perovskites from aillikites of the Bolshaya Tagna intrusion exhibit crystals with normal zoning showing a decrease in Na, REE, and Nb contents with center-to-rim increasing Ca content. In contrast, minerals from the aillikites of the Bushkanay dyke demonstrate reverse zoning, with an increase in Na, REE, and Sr and decrease in Ca contents from the center to the rim. We suggest that during crystallization of perovskites, the magma parental to the aillikites of the Bolshaya Tagna intrusion and the Bushkanay dyke had nearly similar trace element composition, but after crystallization of the cores of perovskite crystals each melt portion evolved independently. The samples from the Bushkanay dyke show an increase in fO2 and the residual magma enrichment in REE, Na, and Sr as evidenced by their elevated contents at the rims of perovskite grains. In the Bolshaya Tagna aillikites after crystallization of perovskite cores, the melt was depleted in REE, Na, and Nb.Based on U-Pb dating of perovskites, the age of aillikites from the Bolshaya Tagna intrusion is 583–654 Ma. Perovskite from aillikites of the Bushkanay dyke is relatively young, with an age of 575 ± 39 Ma. The obtained ages are consistent with the age of formation of Neoproterozoic alkaline-ultramafic carbonatite complexes of the Siberian craton and other occurrences of aillikites in a response to extension of the Rodinia lithosphere.

Similar and divergent responses to salinity stress of jamun (Syzygium cumini L. Skeels) genotypes.

Genetic variation for salt tolerance remains elusive in jamun (Syzygium cumini). Effects of gradually increased salinity (2.0-12.0 dS/m) were examined in 20 monoembryonic and 28 polyembryonic genotypes of jamun. Six genotypes were additionally assessed for understanding salt-induced changes in gas exchange attributes and antioxidant enzymes. Salt-induced reductions in leaf, stem, root and plant dry mass (PDM) were relatively greater in mono- than in poly-embryonic types. Reductions in PDM relative to control implied more adverse impacts of salinity on genotypes CSJ-28, CSJ-31, CSJ-43 and CSJ-47 (mono) and CSJ-1, CSJ-24, CSJ-26 and CSJ-27 (poly). Comparably, some mono- (CSJ-5, CSJ-18) and poly-embryonic (CSJ-7, CSJ-8, CSJ-14, CSJ-19) genotypes exhibited least reductions in PDM following salt treatment. Most polyembryonic genotypes showed lower reductions in root than in shoot mass, indicating that they may be more adept at absorbing water and nutrients when exposed to salt. The majority of genotypes did not exhibit leaf tip burn and marginal scorch despite significant increases in Na+ and Cl-, suggesting that tissue tolerance existed for storing excess Na+ and Cl- in vacuoles. Jamun genotypes were likely more efficient in Cl- exclusion because leaf, stem and root Cl- levels were consistently lower than those of Na+ under salt treatment. Leaf K+ was particularly little affected in genotypes with high leaf Na+. Lack of discernible differences in leaf, stem and root Ca2+ and Mg2+ contents between control and salt treatments was likely due to their preferential uptake. Correlation analysis suggested that Na+ probably had a greater inhibitory effect on biomass in both mono- and poly-embryonic types. Discriminant analysis revealed that while stem and root Cl- probably accounted for shared responses, root Na+, leaf K+ and leaf Cl- explained divergent responses to salt stress of mono- and poly-embryonic types. Genotypes CSJ-18 and CSJ-19 seemed efficient in fending off oxidative damage caused by salt because of their stronger antioxidant defences. Polyembryonic genotypes CSJ-7, CSJ-8, CSJ-14 and CSJ-19, which showed least reductions in biomass even after prolonged exposure to salinity stress, may be used as salt-tolerant rootstocks. The biochemical and molecular underpinnings of tissue tolerance to excess Na+ and Cl- as well as preferential uptake of K+, Ca2+, and Mg2+ need to be elucidated.

MTORc2 in the distal convoluted tubule (DCT) stimulates renal K+ excretion by inhibiting basolateral Kir4.1/Kir5.1 and Na-Cl−cotransporter (NCC) during increasing dietary K+ intake

Background: The mTORc2 is a multiprotein complex and the core components of mTORc2 contain mTOR (a serine/threonine protein kinase) and RICTOR (rapamycin insensitive companion of mTOR). Previous studies have strongly suggested the role of mTORc2 in the regulation of renal K+ excretion by stimulating epithelial Na+ channels (ENaC) and ROMK (Kir1.1) in the aldosterone-sensitive distal nephron (ASDN). The mice with deletion of RICTOR in the distal nephron or in the renal tubules are hyperkalemic during increasing dietary K+ intake. A large body of evidence has demonstrated that HK-induced inhibition of NCC is essential for stimulating renal K+ excretion and this is achieved by inhibiting the basolateral Kir4.1/Kir5.1 heterotetramer in the DCT. However, the role of mTORc2 in the regulation of basolateral Kir4.1/Kir5.1 heterotetramer in the DCT and NCC is not explored. Thus, the aim of the present study is to explore whether mTORc2 in the DCT regulates the basolateral Kir4.1/Kir5.1 of the DCT, NCC activity and renal K+ excretion. Method: We have generated DCT-specific RICTOR KO mice (DCT-RICTOR-KO) with C57BL6/J background by crossing the mice expressing Slc12a3-Cre-ERT2 with Rictorflox/flox mice. We used patch-clamp-technique to examine basolateral Kir4.1/Kir5.1 in early-DCT, immunoblotting and immunofluorescence to examine NCC expression and in vivo measurement of urinary K+-excretion to determine baseline renal K+-excretion (EK). We also used metabolic cage to examine the body weight (BW), food/water intakes, urinary Na+ (UNa) /K+ (UK) excretion rate, and plasma Na+ and K+ concentrations in male(m)/female(f) DCT-RICTOR KO mice and Slc12a3-Cre-ERT2 -Rictorflox/flox mice (control). Results: Overnight-HK intake stimulates RICTOR expression in the kidney and increases Rictor mRNA in the DCT. The deletion of RICTOR in the DCT was confirmed by immunofluorescence staining showing that RICTOR is expressed in parvalbumin-positive tubule (DCT) of control mice but is almost absent in DCT-RICTOR-KO mice. Deletion of RICTOR in the DCT increased the Kir4.1/Kir5.1-mediated K+-currents, hyperpolarized DCT membrane and increased the expression of pWNK4 and pNCC. While the two genotypes did not have significant difference regarding BW, food/water intakes, UNa and plasma Na+ concentrations, m/f DCT-RICTOR KO mice had a significantly lower UK and higher plasma K+ concentrations than their corresponding control. In vivo measurement of baseline renal K+ excretion (EK) also shows that renal-EK was lower and plasma K+ was higher in DCT-RICTOR-KO mice than corresponding control mice. Also, overnight-HK did not inhibit Kir4.1/Kir5.1 activity in the DCT and failed to inhibit the expression of pNCC in DCT-RICTOR-KO mice. Overnight-HK stimulated renal-EK in control mice, but this effect was attenuated in DCT-RICTOR-KO mice. Thus, overnight-HK induced hyperkalemia in DCT-RICTOR-KO mice but not in control mice. Conclusion: The mTORc2 of the DCT plays a significant role in mediating the effect of HK intake on Kir4.1/Kir5.1 activity and NCC expression. Since mTORC2 also stimulates ENaC and ROMK in the ASDN, an increase in Na+-delivery is expected to stimulate ENaC-ROMK-dependent K+-excretion and flow-stimulated renal K+-excretion. The work is supported by NIH Grants DK136491 (LDH) and DK133220 (WHW). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Salinity influence on adsorption of lipid molecules in clay minerals: Results from experiments and calculations

Model compounds, such as 12-Aminohexadecanoic acid and kaolinite, mare utilized to simulate adsorption under different salinities. The experiments showed that the total organic carbon content adsorbed to kaolinite is 0.166% and 0.082% under high and low salinity conditions, respectively. The kaolinite (001) adsorption behavior of organic matter was simulated by molecular dynamics (MD) technology in the presence of Na+. In addition, the adsorption process was not only statistically analysed but the adsorption energy of state organic matter at the clay surface and the sources of adsorption energy are calculated. It is shown that the increase of Na+ is conducive to the adsorption of the organic matter, which is also supported by the experimental results. The adsorption of organic matter is mainly controlled by functional groups of -CH2 on the kaolinite surface. Density functional theory (DFT) calculations further indicate that the 2 s orbital of Na+ is hybridized with -OH of kaolinite and the 2p orbital of -COO- of 12-Aminohexadecanoic acid under bridging action. Thus, the electron compensation mechanism of Na+ was clarified. This study provides a molecular perspective on the interaction mechanisms between organic matter and kaolinite, which is beneficial to the field of biogeochemistry and environmental effects.

Impact of brining and drying processes on the nutritive value of tambaqui fish (Colossoma macropomum).

Preservation of fish as diet ingredient is challenging in many tropical regions due to poor socioeconomic conditions and lack of freezing facilities. So, alternative preservation techniques could be viable to address the issue. The present study evaluated the effect of brine salting (15% w/v) prior to drying at different temperatures on the nutrient profiles of tambaqui fish (Colossoma macropomum). Whole fish samples (n = 48; 792 ± 16 g; 8 months old) were grouped into two as brine-salted and non-salted, and treated at seven different drying temperatures of 30, 35, 40, 45, 50, 55 and 60°C for a period of 23 h each. To evaluate the impact of Maillard reaction, reactive lysine was also quantified. Drying temperature had no effect on the evaluated macro- and micro-nutrients of tambaqui fish (P > 0.05) while brining reduced the overall protein concentration by 6% (58.8 to 55.4 g/100 g DM; P = 0.004). Brining significantly reduced many amino acids: taurine by 56% (7.1 to 3.1 g/kg; P < 0.001), methionine 17% (14.7 to 12.1 g/kg; P < 0.001), cysteine 11% (5.1 to 4.4 g/kg, P = 0.016), and reactive lysine 11% (52.0 to 46.4 g/kg; P = 0.004). However, alanine, arginine, and serine were not affected by brining (P > 0.05). Brining also reduced the concentrations of Se by 14% (149 to 128 μg/kg DM; P = 0.020), iodine 38% (604 to 373 μg/kg DM; P = 0.020), K 42% (9.71 to 5.61 g/kg DM; P < 0.001) and Mg 18% (1.32 to 1.10 g/kg DM; P = < 0.001) versus an anticipated vast increase in Na by 744% (2.70 to 22.90 g/kg DM; P < 0.001) and ash 28% (12.4 to 16.0 g/100g DM; P < 0.001) concentration. Neither brining nor drying temperature induced changes in % lysine reactivity and fat content of tambaqui fish (P > 0.05). Agreeably, results of multivariate analysis showed a negative association between brining, Na, and ash on one side of the component and most other nutrients on the other component. In conclusion, drying without brining may better preserve the nutritive value of tambaqui fish. However, as a practical remark to the industry sector, it is recommended that the final product may further evaluated for any pathogen of economic or public health importance.

Growth, Physiological, and Biochemical Responses of a Medicinal Plant Launaea sarmentosa to Salinity

Launaea sarmentosa is a valuable medicinal plant with adaptability in saline areas, but it is still unclear how it responds to salinity. For the first time, the present study examined the plant’s changes under different soil salinities generated by 50, 100, 200, and 400 mM NaCl in order to elucidate its responses in terms of growth, photosynthesis, water uptake, osmotic adjustment, ion homeostasis, and oxidative stress defense to salinity. The results showed that the plant’s growth was enhanced by 50 mM NaCl with an 18.07% increase in dry biomass compared to the control, whereas higher salinity levels reduced its growth with a 6.39–54.85% decrease in dry biomass. The plant’s growth response indicates that it had tolerance to salinity levels up to 400 mM NaCl. The accumulation of photosynthetic pigments, including chlorophylls (a + b) and carotenoids, was enhanced under salinity, except for a reduced accumulation under 400 mM NaCl. Relative water content decreased while proline content increased in the salt-stressed plants. Moreover, the salt-stressed plants reduced their K+ and NO3− content along with increases in Na+ and Cl− content. The high salt stress level also caused oxidative stress in the plants, which was revealed through the accumulation of malondialdehyde and hydrogen peroxide content. In addition, the salt-stressed plants had increased total phenolic content and the activities of antioxidant enzymes such as catalase, peroxidase, and superoxide dismutase. These physiological and biochemical changes suggest that L. sarmentosa evolved adaptive mechanisms in photosynthesis, osmotic adjustment, ion homeostasis, and antioxidant defense for growing under salt stress.

Exogenous ascorbic acid as a potent regulator of antioxidants, osmo-protectants, and lipid peroxidation in pea under salt stress

Pea (Pisum sativum L.), a globally cultivated leguminous crop valued for its nutritional and economic significance, faces a critical challenge of soil salinity, which significantly hampers crop growth and production worldwide. A pot experiment was carried out in the Botanical Garden, The Islamia University of Bahawalpur to alleviate the negative impacts of sodium chloride (NaCl) on pea through foliar application of ascorbic acid (AsA). Two pea varieties Meteor (V1) and Sarsabz (V2) were tested against salinity, i.e. 0 mM NaCl (Control) and 100 mM NaCl. Three levels of ascorbic acid 0 (Control), 5 and 10 mM were applied through foliar spray. The experimental design was completely randomized (CRD) with three replicates. Salt stress resulted in the suppression of growth, photosynthetic activity, and yield attributes in pea plants. However, the application of AsA treatments effectively alleviated these inhibitory effects. Under stress conditions, the application of AsA treatment led to a substantial increase in chlorophyll a (41.1%), chl. b (56.1%), total chl. contents (44.6%) and carotenoids (58.4%). Under salt stress, there was an increase in Na+ accumulation, lipid peroxidation, and the generation of reactive oxygen species (ROS). However, the application of AsA increased the contents of proline (26.9%), endogenous AsA (23.1%), total soluble sugars (17.1%), total phenolics (29.7%), and enzymatic antioxidants i.e. SOD (22.3%), POD (34.1%) and CAT (39%) in both varieties under stress. Salinity reduced the yield attributes while foliarly applied AsA increased the pod length (38.7%), number of pods per plant (40%) and 100 seed weight (45.2%). To sum up, the application of AsA alleviated salt-induced damage in pea plants by enhancing photosynthetic pigments, both enzymatic and non-enzymatic activities, maintaining ion homeostasis, and reducing excessive ROS accumulation through the limitation of lipid peroxidation. Overall, V2 (Sarsabz) performed better as compared to the V1 (Meteor).

Evidence from experiments, modeling, and field observations for effects of increased salinization on re-distribution of sediment base cations in Taihu Lake, China.

Taihu Lake, the third largest freshwater lake in China, has experienced rapid salinization in the past decades; however, little is known about the impact of sodium (Na) on ion exchange in the lake environment. To explore the potential effect of increased Na on the migration of base cations (Ca and Mg) and resulting redistribution between the water and sediment, we used the adsorption-exchange experiment, MINTEQ modeling to explore the cation exchange induced by high Na input, and its impact on the redistribution of Ca and Mg in Taihu different media. The results indicated that exchanged quantity of Ca and Mg increased with time, and the exchange process reached 90% during 0-4h and reached equilibrium after 24h under 100mg/L Na (the maximum Na concentration in Taihu sediment pore water). Our MINTEQ modeled result indicated that the exchanged quantity of Ca and Mg increased with the increasing Na concentration, with Ca being preferably exchanged over Mg at the same Na concentration. The MINTEQ model further predicted that, in the Taihu lake environment, the exchange adsorption would reach the equilibrium at the concentration of 6000mg/L Na, with exchanged Ca2+ and Mg2+ accounting for 47% and 55% of the total exchangeable Ca and Mg in the sediment, respectively. Although current Na-induced exchange in the Taihu lake has been far from the equilibrium, the MINTEQ result confirmed the existence of this reaction and predicted the potential redistribution of base cations or Ca/Mg ratio in the lake sediment and water phase with further Na increase. Furthermore, our field observations not only confirmed the existence of Na-induced cation exchange in this lake environment but also were generally in agreement with our experimental and modeled results. The increased salinization-induced ion exchange would alter the re-distribution of base cations and the resulting potential ecosystem consequences should be given close attention in this large freshwater lake.

S-ABA Enhances Rice Salt Tolerance by Regulating Na+/K+ Balance and Hormone Homeostasis.

In order to explore the regulating role and the physiological and biochemical mechanisms of trans-abscisic acid (hereinafter referred as S-ABA) in the process of rice growth and development under salt stress, we took Chaoyou 1000 and Yuxiangyouzhan as materials and set up three salt concentration treatments, CK0 (Control treatment), N1 (50 mmol L-1 NaCl), and N2 (100 mmol L-1 NaCl), in potted trials; we aimed to study the mechanism of rice's response to salt stress from the perspective of agricultural traits and physiological biochemicals and to improve rice's resistance to salt stress through exogenously applying the regulating technology of S-ABA. The following results were obtained: Under salt stress, the growth of rice was significantly suppressed compared to CK0, exhibiting notable increases in agricultural indicators, photosynthesis efficiency, and the NA+ content of leaves. However, we noted a significant decrease in the K+ content in the leaves, alongside a prominent increase in NA+/K+ and a big increase in MDA (malondialdehyde), H2O2 (hydrogen peroxide), and O2- (superoxide anion). This caused the cytomembrane permeability to deteriorate. By applying S-ABA under salt stress (in comparison with salt treatment), we promoted improvements in agronomic traits, enhanced photosynthesis, reduced the accumulation of NA+ in leaves, increased the K+ content and the activity of antioxidant enzymes, and reduced the active oxygen content, resulting in a sharp decrease in the impact of salt stress on rice's development. The application of S-ABA decreased the endogenous ABA (abscisic acid) content under salt stress treatment but increased the endogenous GA (gibberellin) and IAA (indole acetic acid) contents and maintained the hormonal homeostasis in rice plants. To summarize, salt stress causes damage to rice growth, and the exogenous application of S-ABA can activate the pouring system mechanism of rice, suppress the outbreak of active oxygen, and regulate NA+/K+ balance and hormone homeostasis in the blades, thus relieving the salt stress.