Accumulation Of Solutes Research Articles

Increasing the Removal of Large Solutes by Kidney Replacement Therapy.

Solutes that accumulate when the kidneys fail range in size from about 40 to 40,000 Da. Their dialytic clearance tends to decrease as their size increases. Disproportionate accumulation of large solutes has therefore long been considered a potential contributor to residual illness in dialysis patients. Early efforts focused on the removal of "middle molecules" with mass from 300 to 2000 Da. The identification of amyloidosis caused by ß2 microglobulin (ß2M) with mass 12,000 Da shifted the focus to low molecular weight proteins. High-flux dialysis and hemodiafiltration increase the clearance of these larger solutes. However non-kidney clearance and solute compartmentalization limit the extent to which their plasma levels can be lowered by increasing their clearance during treatments of standard duration. Clinical benefits of high-volume hemodiafiltration thus cannot readily be accounted for by a reduction in the levels of known large solutes. The accumulation of peptides in the original middle molecular range and the clearance of larger solutes by peritoneal dialysis has been largely neglected. There is new interest in increasing the clearance of solutes even larger than ß2M by "extended dialysis." Ongoing clinical trials will extend our knowledge of the effects of extended dialysis and hemodiafiltration. In the future we might more effectively reduce plasma large solute levels by manipulating their non-kidney clearance, which is now poorly understood. ß2M is the only large solute whose accumulation in kidney failure has been shown to have specific ill effects. Identification of the ill effects of other large solutes might prompt the development of more targeted therapies.

Nanomolar PFOA Concentrations Affect Lipid Membrane Structure: Consequences for Bioconcentration Mechanisms.

Independent methods show that sub-microMolar concentrations of perfluorooctanoic acid (PFOA), a member of the PFAS family of "forever chemicals", change the properties of DPPC vesicle bilayers. Specifically, calorimetry measurements show that PFOA at concentrations as low as 0.1 nM lowers DPPC's gel-liquid crystalline transition enthalpy by several J/g without changing the transition temperature (Tgel-LC), and dynamic light scattering (DLS) data illustrate that PFOA markedly broadens the size distribution of DPPC vesicles. Furthermore, DLS results from PFOA-containing, DPPC vesicle solutions also contain smaller objects having diameters of 30-50 nm. Close inspection of cryo-EM images reveals that DPPC vesicles formed in the presence of PFOA are multilamellar and the smaller objects have a clear bilayer structure similar to niosomes. A consequence of these PFOA-induced changes to DPPC bilayer structure is that the bilayers themselves are more susceptible to secondary solute accumulation. Time resolved emission measurements of Coumarin 152 (C152) report that C152 is 3-fold more likely to partition into the bilayer's acyl chain, hydrophobic interior when PFOA is present, and fluorescence lifetimes from C152 partitioned into the polar region of the lipid bilayer show evidence of PFOA-induced membrane hydration below Tgel-LC.

Stard1 promotes cholestatic liver injury and disease progression by sensitizing to bile acid hepatotoxicity.

Cholestatic liver diseases (CLD) are often accompanied by hepatocellular injury, fibrosis, and cirrhosis due to the intracellular accumulation of solutes that cannot be excreted into bile, including bile acids (BAs). These are synthesized in hepatocytes from cholesterol mainly via the classic pathway and in a lower proportion through the mitochondrial acidic pathway. The latter requires STARD1-dependent cholesterol transport to the mitochondrial inner membrane for metabolism, whose contribution to BA-induced hepatotoxicity and CLD is unknown. Here we show that patients with primary biliary cholangitis exhibit increased expression of STARD1 compared to control subjects. Mice with hepatocyte-specific Stard1 deletion (Stard1Δhep) were more resistant to experimental models of complete (bile duct ligation, BDL) and chemical obstructive cholestasis-induced liver injury, inflammation and fibrosis than Stard1f/f mice. Stard1Δhep mice exhibited reduced hepatic BAs and mitochondrial cholesterol accumulation but increased mitochondrial GSH (mGSH) levels following BDL compared to Stard1f/f mice. Pharmacological mGSH depletion sensitized primary mouse hepatocytes to a mix of BAs mimicking the profile seen in Stard1f/f mice after BDL leading to increased inflammatory response and cytotoxicity. These findings highlight a role for STARD1 in cholestatic liver injury and suggest that its targeting may be of relevance for CLD.

Choroid plexus aging: structural and vascular insights from the HCP-aging dataset

BackgroundThe choroid plexus (ChP), a highly vascularized structure within the ventricles, is essential for cerebrospinal fluid (CSF) production and metabolic waste clearance, crucial for neurofluid homeostasis and cognitive function. ChP enlargement is seen in normal aging and neurodegenerative diseases like Alzheimer’s disease (AD). Despite its key role of in the blood-CSF barrier (BCSFB), detailed studies on age-related changes in its perfusion and microstructure remain limited.MethodsWe analyzed data from 641 healthy individuals aged between 36 and 90, using the Human Connectome Project Aging (HCP-A) dataset. Volumetric, perfusion, and diffusion metrics of the ChP were derived from structural MRI, arterial spin labeling (ASL), and diffusion-weighted imaging (DWI), respectively. Partial correlations were used to explore age-related ChP changes, and independent t-tests to examine sex differences across age decades. One-way ANOVA was employed to compare perfusion characteristics among ChP, gray matter (GM), and white matter (WM). Relationships between volume, perfusion, and diffusion were investigated, adjusting for age and sex. Additionally, the distribution of cyst-like structures within the ChP and their diffusion/perfusion MRI characteristics were analyzed across different age groups.ResultsThe ChP undergoes notable changes with age, including an increase in volume (r2 = 0.2, P < 0.001), a decrease in blood flow (r2 = 0.17, P < 0.001), and elevated mean diffusivity (MD) values (r2 = 0.16, P < 0.001). Perfusion characteristics showed significant differences between the ChP, GM, and WM (P < 0.001). Both the ChP and GM exhibited age-related declines in CBF, with a more pronounced decline in the ChP. A negative correlation was observed between the age-related increase in ChP volume and the decrease in CBF, suggesting compensatory dystrophic hyperplasia in response to perfusion decline. Cyst-like structures in ChP, characterized by lower MD and reduced CBF, were found to be more prevalent in older individuals.ConclusionsOur findings provide a detailed quantitative assessment of age-related changes in ChP perfusion and diffusion, which may affect CSF production and circulation, potentially leading to waste solute accumulation and cognitive impairment.Grant supportThis work was supported in part by the NIH U01AG052564, P30AG066512, P01AG060882, RF1 NS110041, R01 NS108491, U24 NS135568.

Mitigating salt stress in Zea mays: Harnessing Serratia nematodiphila-biochar-based seed coating for plant growth promotion and rhizosphere microecology regulation

Salt stress poses a significant challenge in contemporary agricultural practices. In response, using plant growth-promoting bacteria (PGPB) in conjunction with biochar coatings has emerged as an innovative biological strategy to mitigate salt stress in crops. Through a dual screening process based on gradient salt concentration and plant growth-promoting performance, a highly salt-tolerant PGPB, Serratia nematodiphila, was identified in this study. And a seed-coating formulation incorporating S. nematodiphila was developed using biochar as a carrier. With the help of potting experiments, this paper investigated the impact of this S. nematodiphila-biochar-based seed coating on Zea mays under salt stress, while also analyzing functional alterations in the core microbial community. These findings indicate that the S. nematodiphila-biochar-based seed coating selectively enriched beneficial microbial populations, such as Proteobacteria, Gammaproteobacteria, Verrucomicrobiae, and Bacteroidia, fostering a symbiotic association with the Z. mays root system. These beneficial consortia facilitated the accumulation of osmotic solutes, including soluble sugars, soluble proteins, and proline, thereby modulating leaf photosynthetic activity and alleviating salt stress (sodium and potassium homeostasis) in Z. mays. This investigation provides refined technical approaches for alleviating salt stress in Z. mays, contributing to developing sustainable agricultural practices.

Chitosan induced cold tolerance in Kobresia pygmaea by regulating photosynthesis, antioxidant performance, and chloroplast ultrastructure.

Cold stress is the primary factor that limits the growth and development of Kobresia pygmaea in the Tibetan Plateau, China. Chitosan (CTS) has been recognized for its ability to enhance agricultural production and tolerance to stress. This study examined the effect of treating seedlings under cold stress with chitosan. The results demonstrated that cold stress inhibited the growth of seedlings and adversely affected the photosynthetic capacity [net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), maximum efficiency of photosystem II (Fv/Fm), quantum yield of photosystem II (φ PSII ), electron transport rate (ETR), and non-light-induced non-photochemical fluorescence quenching Y(NPQ)] and destroyed PSII and the chloroplast structure. Under regular temperatures, low concentrations of CTS (0.005% and 0.01%) inhibited the soluble protein content, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) activity, and photosynthetic capacity. However, the application of 0.015% CTS increased the levels of soluble sugar, fructose, and protein, as well as those of the levels of ions, such as iron and magnesium, chlorophyll, photosynthetic capacity, and the activities of Rubisco, superoxide dismutase, and phenylalanine amino-lyase (PAL). Under cold stress, treatment with CTS decreased the contents of starch and sucrose; improved the contents of fructose, soluble protein, and antioxidants, such as ascorbic acid and glutathione; and enhanced the photosynthesis capacity and the activities of Rubisco, chitinase, and PAL. Exogenous CTS accelerated the development of the vascular bundle, mitigated the damage to chloroplast structure induced by cold, and promoted the formation of well-organized thylakoids and grana lamellae. Additionally, CTS upregulated the expression of genes related to cold tolerance in K. pygmaea, such as KpBSK2/KpERF/KpDRE326. These findings indicate that CTS enhances the cold tolerance in K. pygmaea by improving development of the vascular bundle, increasing the accumulation of solutes and antioxidants, regulating the transformation of carbohydrates, repairing the chloroplast structure, and maintaining the photosynthetic capacity and Rubisco activity.

Modulation of irrigation-induced microbial nitrogen‑iron redox to per- and polyfluoroalkyl substances' water-soil interface release in paddy fields: Activation or immobilization?

Understanding the modulation of paddy field irrigation to the migration of per- and polyfluoroalkyl substances (PFAS) at the water-soil interface is pivotal for the management of PFAS pollution in paddy soil and surrounding surface water environments. In flooded soils, soil organic matter was transformed into aromatic protein-like dissolved organic matter (DOM). Meanwhile, Na+, K+, and Mg2+ were translocated into extracellular polymeric substances (EPS) under the catalysis of cation channel enzymes (p < 0.05), provided ion bridging for the binding of DOM and PFAS, and accelerated the accumulation of C4–C9 PFAS in overlying water (41.79–99.14 %). Short-chain PFAS's accumulation in soil solution of drought soils was stimulated by microorganisms secreting soluble microbial by-product-like DOM (53.15–97.96 %). Furthermore, PFAS's distribution in flood soils was dominated by bacterial denitrification and iron-reduction, whereas iron-oxidation and ammoxidation controlled that in drought soils. The transformation of organic carbon including CO and COC caused by irrigation-induced redox modulated PFAS cross-media translocation. Iron‑nitrogen redox in flooded paddy soils immobilized the PFAS's migration into overlying water (p < 0.05). Our findings have profound implications for PFAS's pollution control, surface water environmental protection, and rice production security in paddy fields.

Growing Macrophages Regulate High Rates of Solute Flux by Pinocytosis.

Murine macrophages growing in response to colony-stimulating factor-1 (CSF1) require pinocytosis. High rates of solute influx and accumulation by pinocytosis are regulated by CSF1 and leucine. Low molecular weight products of protein hydrolysis in lysosomes recycle efficiently from the cells.

Thermodynamic behavior and microstructure evolution of Inconel 718 alloy by laser metal deposition

The temperature evolution, stress evolution, and dendrite growth during the laser metal deposition (LMD) process of Inconel 718 alloy were simulated using a multi-scale model that combines the finite element method and the Cellular Automata (CA) method. This model established the relationship between the thermal behavior of the molten pool and the solidification characteristics, and predicted the morphological size of the solidified structure. Research indicates that under conditions of higher cooling rate and lower shape control factor, equiaxed grains are prone to form, with a lower degree of elemental segregation in this region, which is conducive to the precipitation of granular Laves phase. Conversely, under conditions of lower cooling rate and higher shape control factor, columnar grains are more likely to form, with a higher degree of elemental segregation in this region, leading to the precipitation of chain-like Laves phase. The results of thermo-mechanical coupled simulation suggest that the maximum transient thermal stress is located at the overlap position, and when the component cools down to room temperature, the maximum normal stress along the scanning direction is observed. Dendritic growth results demonstrate that during the equiaxed grain growth process in the top region of the melt pool, the released solute is constrained by time and space, leading to the accumulation of solute and the formation of interdendritic segregation. In areas with a higher grain density, the solute accumulation zones overlap, resulting in an increase in solute concentration, which inhibits dendrite growth. In the middle region of the melt pool, during the columnar grain growth process, the solute concentration in the gaps between adjacent grains continuously increases, resulting in micro-segregation phenomena. Experimental measurements have shown that the temperature field's melt pool morphology, stress values along the scanning path, and dendritic morphology are in good agreement with the experimental outcomes.

Hybrid Protocells Based on Coacervate-Templated Fatty Acid Vesicles Combine Improved Membrane Stability with Functional Interior Protocytoplasm.

Prebiotically-plausible compartmentalization mechanisms include membrane vesicles formed by amphiphile self-assembly and coacervate droplets formed by liquid-liquid phase separation. Both types of structures form spontaneously and can be related to cellular compartmentalization motifs in today's living cells. As prebiotic compartments, they have complementary capabilities, with coacervates offering excellent solute accumulation and membranes providing superior boundaries. Herein, protocell models constructed by spontaneous encapsulation of coacervate droplets by mixed fatty acid/phospholipid and by purely fatty acid membranes are described. Coacervate-supported membranes form over a range of coacervate and lipid compositions, with membrane properties impacted by charge-charge interactions between coacervates and membranes. Vesicles formed by coacervate-templated membrane assembly exhibit profoundly different permeability than traditional fatty acid or blended fatty acid/phospholipid membranes without a coacervate interior, particularly in the presence of magnesium ions (Mg2+). While fatty acid and blended membrane vesicles are disrupted by the addition of Mg2+, the corresponding coacervate-supported membranes remain intact and impermeable to externally-added solutes. With the more robust membrane, fluorescein diacetate (FDA) hydrolysis, which is commonly used for cell viability assays, can be performed inside the protocell model due to the simple diffusion of FDA and then following with the coacervate-mediated abiotic hydrolysis to fluorescein.

Deciphering chemical and physical processes that give rise to natronization in a shallow aquifer in an arid zone

Groundwater provides a reliable and stable alternative to surface water resources in arid and semiarid regions to meet human and environmental needs. However, excessive exploitation in the last decades has led to significant salinization of groundwater and soils in many parts of the world. In the highlands of central-north Mexico, a number of agriculturally used aquifers show increasing salinization effects. Tierra Nueva is a case where salt precipitations in recent years have made land mostly unsuitable for agriculture. It is assumed that the intensive irrigation under dry climatic conditions, together with the presence of argillaceous horizons at shallow depth and the alteration of Na-rich volcanic rocks, determine the occurrence of specific salinization processes producing evaporite minerals in excess. This investigation provides physical and chemical evidence of groundwater processes explaining the accumulation of solutes in groundwater and soils. It shows that the principal evolutionary processes in the studied aquifer were water-rock interactions and evaporation, while ionic exchange processes dominated the water circulating through the clay-sandy materials of the valley. Geochemical models show that recharging water dissolved CO2 from the unsaturated zone, and reacted with silicates (i.e. hydrolysis of albite, K-feldspar, and biotite), underwent cation exchange, and precipitated kaolinite. In the discharge area, the mineral natron was dissolved, while thermonatrite, natrolite (Na-natrolite), nontronite (Ca-nontronite, K-nontronite, Mg-nontronite, Na-nontronite) were formed, among other reactions. This salinization process eventually leads to soils which are unsuitable for agricultural activities. The study of this phenomenon represents an important contribution to the understanding of the implications of the expansion of arid and semiarid lands.

Acumulación y degradación de solutos en bayas Vitis vinifera L. en climas contrastantes

Grape ripening is a complex process conditioned by climatic factors, which influence the evolution of solutes and define its composition. The objective of the study was to evaluate the behavior of the red Tannat variety in contracting climatic situations, considering the dynamics of berry growth, the rate of accumulation and reduction of solutes during ripening, and their composition at harvest. The trial was installed in two regions, warm and temperate climate, in rainfed commercial vineyards, during 2018 and 2019. Primary berry composition at ripening and secondary composition at harvest were determined. Multivariate analysis and comparison of means (Fisher’s LSD test) were performed. The climatic type (region) conditions the evolution of solutes at ripening, but their interaction with annual conditions determines berry composition. The annual variability is explained by rainfall, with a direct influence on the duration of the cycle and the ripening, size, and composition of the berry. In warm climates, there is greater sensitivity to the ripening year effect, with a strong influence on the rapid phase. In temperate climates, the greater stability between years results from a thermal condition more favorable to ripening processes.

New insights into the parameterization of the dry surface layer and its hydrogeochemical mechanism: An experimental study

Knowledge of the parameterization of the dry surface layer (DSL) is essential for evaluating near-surface water flow and water balance in arid and semi-arid areas. Existing studies have parameterized DSL thickness and vapor flow as functions of the soil moisture content (SMC) in the surface layer to predict soil evaporation. However, hydrochemical processes related to DSL development have been ignored, including changes in hydrochemistry, the underlying hydrochemical mechanism, and the role of dissolved substances in the DSL development. Herein, we performed a series of soil evaporation experiments for 260 days and explored the factors influencing DSL development (e.g., soil texture, atmospheric temperature, SMC, solutes). Evaporation experiments were performed using silty loess, sandy loess, and fine sand with a 60-cm water table. Results showed that the cumulative evaporation of silty loess, sandy loess, and fine sand over the experimental period were 1,391.52, 460.10, and 185.53 mm, respectively, which determined by the maximum height of liquid flow continuity. The content of total dissolved solids (TDS) and major ions at the surface soil were significantly higher than the values at deep depths of 5‒55 cm, which largely depend on evaporative water loss. Evolutionary trends of chemical facies in sand media along the liquid water migration were from HCO3-Ca type to SO4·Cl-Na type. This was attributed to mineral dissolution at a depth of 5–55 cm and their transport with liquid water, resulting in the precipitation of salt crystals at the surface soil. Furthermore, a consolidated DSL with a thickness of 3.0–3.5 cm in the sandy loess and a loose DSL with a thickness of 1.5–2.0 cm in fine sand were observed at the end of the experiments. The accumulation of solutes at the surface leads to a reduction in effective porosity and the aggregation of soil particles during continuous drying, which facilitates the consolidation of DSL in sandy loess. This overestimated the DSL thickness, resulting in a difference between the experimental and predicted evaporation rates by Fick's law. Overall, these results highlight the limitations of considering DSL thickness as a function of SMC only, providing new insights into hydrochemical processes and dissolved solutes involving DSL parameterization during continuous soil drying.

Sorghum drought tolerance is enhanced by cerium oxide nanoparticles via stomatal regulation and osmolyte accumulation

Sorghum [Sorghum bicolor (L.) Moench] yield is limited by the coincidence of drought during its sensitive stages. The use of cerium oxide nanoparticles in agriculture is minimal despite its antioxidant properties. We hypothesize that drought-induced decreases in photosynthetic rate in sorghum may be associated with decreased tissue water content and organelle membrane damage. We aimed to quantify the impact of foliar application of nanoceria on transpiration rate, accumulation of compatible solutes, photosynthetic rate and reproductive success under drought stress in sorghum. In order to ascertain the mechanism by which nanoceria mitigate drought-induced inhibition of photosynthesis and reproductive success, experiments were undertaken in a factorial completely randomized design or split-plot design. Foliar spray of nanoceria under progressive soil drying conserved soil moisture by restricting the transpiration rate than water spray, indicating that nanoceria exerted strong stomatal control. Under drought stress at the seed development stage, foliar application of nanoceria at 25 mg L−1 significantly improved the photosynthetic rate (19%) compared to control by maintaining a higher tissue water content (18%) achieved by accumulating compatible solutes. The nanoceria-sprayed plants exhibited intact chloroplast and thylakoid membranes because of increased heme enzymes [catalase (53%) and peroxidase (45%)] activity, which helped in the reduction of hydrogen peroxide content (74%). Under drought, compared to water spray, nanoceria improved the seed-set percentage (24%) and individual seed mass (27%), eventually causing a higher seed yield. Thus, foliar application of nanoceria at 25 mg L−1 under drought can increase grain yield through increased photosynthesis and reproductive traits.

An insight into the influence of precipitation phase on the surface quality in diamond turning of an Aluminium alloy

Diamond turning is an effective technology for processing metal mirrors used in photoelectric communications, radar, and other fields. In diamond turning, the precipitated phase is an essential factor that influences the surface quality of the metal mirrors. However, in previous studies, the precipitation phase has typically been handled as a random variable in a surface morphology model to evaluate its influence on the surface roughness, instead of determining the formation mechanism and proposing suppression solutions. In this study, a new phenomenon is observed in the diamond turning of metal mirrors, that is, the micro diamond tool can reduce the protrusion of the precipitated phase under a small feed rate and improve the surface quality. Investigating the turning process using diamond tools with varying tool nose radii at small feed rates (<1 μm/r), the underlying transformation mechanism of the precipitation phase is determined with the advanced material characterization technologies. The growth of the precipitated phase with an increase in the tool nose radius is explained using the energy gradient theory. The results showed that the increased material strain on the machined surface decreased the activation energy of solute diffusion in the material, causing solute accumulation and precipitate phase growth. With a further increase of tool nose radius to around 1000 μm, the β'' phase breaks and rotates. The representative volume element method shows that when undergoing severe plastic deformation, dislocations and grain boundaries quickly aggregate and slide on the precipitated phase, which will lead to the fracture and rotation of β'' phase. These findings provide a theoretical basis for the development of highly smooth mirrors.

Numerical study of concentration polarization of reverse osmosis film via the lattice Boltzmann method

The concentration polarization is the main factor affecting the water production rate of reverse osmosis. This article proposes a new numerical model based on the lattice Boltzmann method for simulating concentration polarization that can easily handle the computational instability caused by small diffusion coefficient. Based on this model, the concentration polarization in empty channel and unilateral spacer channel are simulated, respectively. The results show that the thickness of the CPL is generally about one tenth of the channel height. Increasing the Re can weaken concentration polarization, reduce the thickness of the CPL, and thereby increase permeate flux. Increasing the TMP can increase permeation flux, but it also accelerates the accumulation of solute increases the solute concentration within the CPL, and accelerates fouling. The spacer can effectively weaken the concentration polarization and increase permeate flux. But the unilateral spacer can cause uneven performance of the upper and bottom membranes.

Uniformity of microbial injection for reinforcing saturated calcareous sand: A multi-test approach

The mineralization process of microbial-induced calcium carbonate precipitation (MICP) is influenced by many factors, and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for MICP technology. In this study, the uniformity of the saturated calcareous sand treated with MICP was investigated through one-dimensional calcareous sand column tests and model tests. The coefficient of variation was employed in one-dimensional sand column tests to investigate the impact of injection rate, cementation solution concentration, and number of injection cycles on the uniformity of the MICP treatment. Additionally, model tests were conducted to investigate the impact of injection pressure and methods on the treatment range and uniformity under three-dimensional seepage conditions. Test results demonstrate that the reinforcement strength and uniformity are significantly influenced by the injection rate of the cementation solution, with a rate of 3 mL/min, yielding a favorable treatment effect. Excessive concentration of the cementation solution can lead to significant non-uniformity and a reduction in the compressive strength of MICP-treated samples. Conversely, excessively low concentrations may result in decreased bonding efficiency. Among the four considered concentrations, 0.5 mol/L and 1 mol/L exhibit superior reinforcing effects. The morphological development of calcareous sandy foundation reinforcement is associated with the spatial distribution pattern of the bacterial solution, exhibiting a relatively larger reinforcement area in proximity to the lower region of the model and a gradually decreasing range towards the upper part. Under three-dimensional seepage conditions, in addition to the non-uniform radial cementation along the injection pipe, there is also vertical heterogeneity of cementation along the length of the injection pipe due to gravitational effects, resulting in preferential deposition of calcium carbonate at the lower section. The application of injection pressure and a double-pipe circulation injection method can mitigate the accumulation of bacterial solution and cementation solution at the bottom, thereby improving the reinforcement range and uniformity.

Coping with salinity stress: segmental group 7 chromosome introgressions from halophytic Thinopyrum species greatly enhance tolerance of recipient durum wheat.

Increased soil salinization, tightly related to global warming and drought and exacerbated by intensified irrigation supply, implies highly detrimental effects on staple food crops such as wheat. The situation is particularly alarming for durum wheat (DW), better adapted to arid/semi-arid environments yet more sensitive to salt stress than bread wheat (BW). To enhance DW salinity tolerance, we resorted to chromosomally engineered materials with introgressions from allied halophytic Thinopyrum species. "Primary" recombinant lines (RLs), having portions of their 7AL arms distally replaced by 7el1L Th. ponticum segments, and "secondary" RLs, harboring Th. elongatum 7EL insertions "nested" into 7el1L segments, in addition to near-isogenic lines lacking any alien segment (CLs), cv. Om Rabia (OR) as salt tolerant control, and BW introgression lines with either most of 7el1 or the complete 7E chromosome substitution as additional CLs, were subjected to moderate (100 mM) and intense (200 mM) salt (NaCl) stress at early growth stages. The applied stress altered cell cycle progression, determining a general increase of cells in G1 and a reduction in S phase. Assessment of morpho-physiological and biochemical traits overall showed that the presence of Thinopyrum spp. segments was associated with considerably increased salinity tolerance versus its absence. For relative water content, Na+ accumulation and K+ retention in roots and leaves, oxidative stress indicators (malondialdehyde and hydrogen peroxide) and antioxidant enzyme activities, the observed differences between stressed and unstressed RLs versus CLs was of similar magnitude in "primary" and "secondary" types, suggesting that tolerance factors might reside in defined 7el1L shared portion(s). Nonetheless, the incremental contribution of 7EL segments emerged in various instances, greatly mitigating the effects of salt stress on root and leaf growth and on the quantity of photosynthetic pigments, boosting accumulation of compatible solutes and minimizing the decrease of a powerful antioxidant like ascorbate. The seemingly synergistic effect of 7el1L + 7EL segments/genes made "secondary" RLs able to often exceed cv. OR and equal or better perform than BW lines. Thus, transfer of a suite of genes from halophytic germplasm by use of fine chromosome engineering strategies may well be the way forward to enhance salinity tolerance of glycophytes, even the sensitive DW.

Reduction in Apparent Permeability Owing to Surface Precipitation of Solutes by Drying Process and Its Effect on Geological Disposal

Disposal tunnels in geological repositories are ventilated continuously for over 50 years until their closure. Under these conditions, an unsaturated zone of mixed liquid and gas phases forms around the tunnels. Moreover, drying is assumed to progress from the host rock to the tunnels. To understand these drying processes, this study investigated the migration and precipitation of solutes via capillary forces during drying in packed columns using silica sand or glass beads as packed layers and X-ray CT analysis. In addition, the apparent permeability of a column packed with silica sand containing precipitation was examined using a flow experiment. The results indicate that the precipitation and accumulation of solutes were significant near the drying surfaces of the columns. The apparent mass transfer coefficient at a relatively early stage of the drying process indicates that the migration rate of solutes depends strongly on the capillary forces during the drying process. Furthermore, the apparent permeability of the columns with precipitation decreased significantly. These indicate that the precipitation and accumulation of solutes with drying in the groundwater reduce the porosity and permeability, and the advection of groundwater around the repository may be suppressed.

Sustainable water solutions:a Six Sigma approach to membrane-based filtration system design

Water contamination is a major problem nowadays which can not only be solved through technological innovations but also requires educational innovation. The contamination of water is caused by discharging harmful pollutants into the water. These harmful contaminants cause different diseases. The significance of water filtration has grown in recent years. The quality of water is affected majorly by residual waste, bacteria, and so on. Based upon these issues, the Six Sigma methodology is used in this research for the design of a portable filtration system. This methodology is based on five steps that align with the computational competencies involving abstraction, decomposition of problem, and algorithmic thinking. Initially, a questionnaire approach is used to identify the need for a portable water filter for potential users. The Quality Function Development (QFD) matrix is used to measure the user’s needs. Based on the user’s information, a decision matrix tool is being used in the Analyze stage. After this theoretical concept is generated, and selection is made among various options. The complete drawing was made in the design stage after several stages of concept generation and selection. Then a prototype is developed to conduct proof of concept testing. The hollow fiber membrane (HFM) that is being used is manufactured usually by melt spinning, dry spinning, and wet spinning. But usually, a wet spinning method is predominantly used for manufacturing hollow fiber membranes. Polymer liquid like polyvinyl chloride (PVC) is used for the manufacturing of membranes with other liquids in different ratios. The size of pores varies from 0.01 to 0.1 microns. The flux rate usually depends upon the volume, length, and size of the cartridge. Backwashing at regular intervals is done for the presentation of fooling due to the accumulation of solutes. This filtration system is also proficient in rejecting bacteria that are being found in water and soil. This is done by a coliform test that is being performed for bacteria. The porosity of the membrane is also affected by the concertation of polyvinyl chloride (PVC) as the concentration of polyethylene glycol increases the porosity of the membrane decreases. A Chemical Oxygen Demand test is also performed to check the presence of organic matter in water. After filtration, no organic matter was manifested in the water. Design for Six Sigma in a portable filtration system that uses membrane for filtration is a good start in looking for a new alternative concept. The implication of this research presents a multifaceted solution to water contamination issues, offering educational outreach programs, STEM education integration, community engagement, and innovative competitions as integral components for fostering awareness, sustainable practices, and creative solutions in the pursuit of clean water.