Salt Leaching Research Articles

Comparison of the Influence of 45S5 and Cu-Containing 45S5 Bioactive Glass (BG) on the Biological Properties of Novel Polyhydroxyalkanoate (PHA)/BG Composites.

Polyhydroxyalkanoates (PHAs), due to their biodegradable and biocompatible nature and their ability to be formed in complex structures, are excellent candidates for fabricating scaffolds used in tissue engineering. By introducing inorganic compounds, such as bioactive glasses (BGs), the bioactive properties of PHAs can be further improved. In addition to their outstanding bioactivity, BGs can be additionally doped with biological ions, which in turn extend the functionality of the BG-PHA composite. Here, different PHAs were combined with 45S5 BG, which was additionally doped with copper in order to introduce antibacterial and angiogenic properties. The resulting composite was used to produce scaffolds by the salt leaching technique. By performing indirect cell biology tests using stromal cells, a dose-depending effect of the dissolution products released from the BG-PHA scaffolds could be found. In low concentrations, no toxic effect was found. Moreover, in higher concentrations, a minor reduction of cell viability combined with a major increase in VEGF release was measured. This result indicates that the fabricated composite scaffolds are suitable candidates for applications in soft and hard tissue engineering. However, more in-depth studies are necessary to fully understand the release kinetics and the resulting long-term effects of the BG-PHA composites.

THE MAIN ELEMENTS OF THE TECHNOLOGY OF SOYBEAN VARIETIES CULTIVATION ON LOW SALINE SOILS IN KHOREZM REGION, UZBEKISTAN

The optimal timing of sowing soybean varieties on low saline soils of the Khorezm region is one of the most important agricultural practices. The material presented indicates that the land and water resources and thermal regime of the region are sufficient to ensure the growth and development and complete ripening of all soybean varieties with the highest possible efficiency. Analyzing the data obtained, it is necessary to indicate that in low saline soils of Khorazm region the best sowing dates for varieties Dustlik, Eureka 357 and Orzu are in the second decade of May. The use of rizotorphin while sowing soybean seeds leads to increased yields. Cultivated soybean varieties using rizotorphin leave on the field more crop residues, rich in nitrogen, and therefore are excellent forecrops for other agricultural plants. Preliminary salt leaching and land reclamation measures to combat negative impact of soil salinization are absolutely necessary before sowing soy.

Porous Architecture Evaluation of Silk Fibroin Scaffold from Direct Dissolution Salt Leaching Method

AbstractTissue engineering scaffold is used to facilitate and support cell/tissue growth. Fabrication of silk fibroin scaffold using newly developed direct dissolution salt leaching method is successfully done. This method significantly reduces the processing time compared to the traditional method. Cells attachment, cells growth, cells migration, and diffusion of nutrients and waste are affected by the architecture scaffold. In this study, 3D analysis on porous architecture evaluation of direct dissolution salt leaching scaffolds is conducted. Scaffolds are fabricated from different NaCl particle sizes of 158, 250, 378, and 503 μm at 12% w/v silk fibroin concentration. Scaffold architecture is evaluated using microcomputed tomography (micro‐CT) method. Evaluation of scaffold architecture shows that the use of larger NaCl particle size increases the scaffold pore size. The relationship between scaffold pore size and scaffold porosity, scaffold wall thickness, pore interconnectivity, scaffold specific surface area is established, which is important for tissue formation.

Effects of water application intensity of micro-sprinkler irrigation and soil salinity on environment of coastal saline soils

To achieve the greatest leaching efficiency, water movement must occur under unsaturated flow conditions. Accordingly, the water application intensity of irrigation must be chosen carefully. The aim of this study was to evaluate the impact of the water application intensity of micro-sprinkler irrigation on coastal saline soil with different salt contents. To achieve this objective, a laboratory experiment was conducted with three soil salinity treatments (2.26, 10.13, and 22.29 dS/m) and three water application intensity treatments (3.05, 5.19, and 7.23 mm/h). The results showed that the effect of soil salinity on soil water content, electrical conductivity, and pH was significant, and the effect of the water application intensity was insignificant. High soil water content was present in the 40–60 cm profile in all soil salinity treatments, and the content was higher in the medium and high water application intensity treatments than in the low-intensity treatment. Significant salt leaching occurred in all treatments, and the effect was stronger in the high soil salinity treatment and medium water application intensity treatment. In the medium and high soil salinity treatments, pH exhibited a decreasing trend, with no trend change in the low soil salinity treatment, and the pH value was higher in the medium water application intensity treatment than in the other two treatments. These results indicated that the three intensities evaluated had no statistically different effect on the electrical conductivity of saturated soil-paste extracts (EC) in the upper 20 cm of the soil profile, and it would be better to maintain a lower value of the water application intensity.

The extraction of Ta, Nb and rare earths from fergusonite by using KOH sub-molten salt leaching

It is very important to efficiently extract Ta, Nb and rare earths from polymetallic ore such as fergusonite. A new method combining an alkaline leaching of sub-molten salt (SMS) and an acid leaching is recommended for extracting Ta, Nb and rare earths from fergusonite concentrate using an environmentally friendly process.The leaching yields of Ta and Nb from the concentrate reached to 98% and 99%, respectively under the most suitable KOH SMS leaching conditions, KOH concentration 80 wt%, leaching temperature 300C, KOH to concentrate mass ratio 3, stirring speed 800 rpm, leaching time 1 h. The overall recovery of Ta and Nb were 96% and 97%, respectively, and the total content of Ta and Nb in the crude Ta-Nb product was 98.6% (45.1%-Ta2O5, 53.5%-Nb2O5) when the solid to liquid mass ratio in the diluting stage was 1:2 and KOH concentration in the evaporating concentration stage was 30 wt%. The recovery yield of rare earths (96.5%-RE2O3) reached to 92% when the KOH SMS leach residue was leached with 15 wt% HCl solution.

Salt leaching using powder (SLUP) process for glass/chitosan scaffold elaboration for biomaterial applications

Tissue engineering has emerged as an alternative approach to create bone tissue by growing cells on 3D scaffolding. The aim of this study was to synthesize a composite glass/chitosan (BG-CH) by using new salt leaching using powder (SLUP) process in order to control the porosity rate and then the chemical reactivity of the final product. SLUP process consists on the cavity creation with desired pore sizes. It does not require heat treatment. This process is based on washing out the NaCl particles used for that. It is due to its high solubility in aqueous media. This work focuses on the elaboration, physicochemical, and chemical reactivity studies of pure bioactive glass and bioactive glass associated with chitosan. A range of composite scaffolds with different bioactive glass/chitosan contents has been synthesized. NaCl with a distinct range size was used with the aim of optimizing the pore network. Obtained results show that the specific surface area and pore volume increase with increasing of chitosan and porogen content. The same observations for pore volume were registered. The obtained scaffolds had high porosity (90%) with good pore connectivity. SEM images revealed strong dependence of sizes and shapes of pores on the salt/composite ratios.

Reconstruction of Climate and Landscapes of the Medieval Period on the Basis of Palynological Study of Paleosols Buried under Kurgans and Dendrochronological Data from Altai (South of Western Siberia)

Light loamy ordinary chernozems buried under two kurgans of a large Early Medieval necropolis Srostki-1 constructed in 890 ± 105…975 ± 85 AD (calibration by 1δ) were compared with the chernozem of the background territory in Biysk district of Altai. The analysis of pedological and 20 geochemical indices characterizing weathering, biological activity, and salt leaching demonstrated that the paleosols of the Medieval period in the phase before the construction of the kurgans had been formed in a somewhat drier climate compared to the modern conditions, and then the humidization of the paleoclimate began. According to palynological data, the considered period was characterized by a decrease in the area of pine stands, which could be due to colder winters. The areas of birch and riverine willow forests also decreased in comparison with the modern period because of the active cutting by humans of the Srostki ethnos. In the Medieval period, mesophytic rich forb communities occupied larger areas and predominated over dry-steppe communities. The growth of sedges was active on expanding marshes that appeared after drying of shallow water bodies upon the decrease in the water-protective role of forest vegetation. At the same time, a slight increase in the amount of pollen of xerophytic herbs, including representatives of Chenopodiaceae and Poaceae families and Artemisia genus took place. This could be related to the increased anthropogenic load, including soil disturbance upon the construction of 61 kurgans of the Srostki culture. Dendrochronological method was applied to reconstruct average summer temperatures over the past two thousand years. It was found that the heat supply of summer seasons in the Srostki period (8th–12th centuries AD) generally corresponded to that at present. However, the years of 850–870 and 930–950 AD were marked by summer cooling, and the years of 876–882 and 982 AD were marked by summer warming with average summer temperatures 1.5°C higher than the reference values of 1961–1990. The climatic variability of the Medieval period in different regions of the south of Western Siberia attests to the metachronous dynamics of the climate specified by the local conditions against the background of general climatic trends typical of Central Asia.

Mechanical Properties of Porous Polylactic Acid (PLA) Via Salt Leaching Method

The purpose of this research is to evaluate the properties and characterization of porous polylactic acid (PLA). The porous PLA was fabricated via salt leaching method whereas PLA was first dissolved in chloroform under mechanical stirring for 7 minutes. Then, sodium chloride (NaCl) was added into the dissolved PLA. The mixture of PLA and NaCl was then left at room temperature for 24 hours for the chloroform to be evaporated. The solidified films was then been washed under tab water to remove the NaCl content. The removal of NaCl content will lead to porous PLA. The effect of NaCl content on the mechanical and morphological properties of PLA was been studied. The increased of NaCl content shown a reduction trend for tensile properties and elongation at break. Meanwhile, the Young’s modulus had been found to increase with increasing NaCl content. The micrograph of the neat PLA showed a smooth surface at the tensile fractured surface. However, the effect of salt leaching method lead to a porous PLA as the NaCl content increased, the pores observed in the micrographs also increased. The higher the content of NaCl increashe amount of pores on the PLA and the number of interconnected pores with uniform pores morphology and well distributed pores.

Salt Tolerance and Na Allocation in Sorghum bicolor under Variable Soil and Water Salinity.

Salinity is a major constraint for plant growth in world areas exposed to salinization. Sorghum bicolor (L.) Moench is a species that has received attention for biomass production in saline areas thanks to drought and salinity tolerance. To improve the knowledge in the mechanisms of salt tolerance and sodium allocation to plant organs, a pot experiment was set up. The experimental design combined three levels of soil salinity (0, 3, and 6 dS m−1) with three levels of water salinity (0, 2–4, and 4–8 dS m−1) and two water regimes: no salt leaching (No SL) and salt leaching (SL). This latter regime was carried out with the same three water salinity levels and resulted in average +81% water supply. High soil salinity associated with high water salinity (HSS-HWS) affected plant growth and final dry weight (DW) to a greater extent in No SL (−87% DW) than SL (−42% DW). Additionally, HSS-HWS determined a stronger decrease in leaf water potential and relative water content under No SL than SL. HSS-HWS with No SL resulted in a higher Na bioaccumulation from soil to plant and in translocation from roots to stem and, finally, leaves, which are the most sensitive organ. Higher water availability (SL), although determining higher salt input when associated with HWS, limited Na bioaccumulation, prevented Na translocation to leaves, and enhanced selective absorption of Ca vs. Na. At plant level, higher Na accumulation was associated with lower Ca and Mg accumulation, especially in No SL. This indicates altered ion homeostasis and cation unbalance.

Poly(3-hydroxybutyrate)/hydroxyapatite/alginate scaffolds seeded with mesenchymal stem cells enhance the regeneration of critical-sized bone defect.

A critical-sized calvarial defect in rats is employed to reveal the osteoinductive properties of biomaterials. In this study, we investigate the osteogenic efficiency of hybrid scaffolds based on composites of a biodegradable and biocompatible polymer, poly(3-hydroxybutyrate) (PHB) with hydroxyapatite (HA) filled with alginate (ALG) hydrogel containing mesenchymal stem cells (MSCs) on the regeneration of the critical-sized radial defect of the parietal bone in rats. The scaffolds based on PHB and PHB/HA with desired shapes were prepared by two-stage salt leaching technique using a mold obtained by three-dimensional printing. To obtain PHB/HA/ALG/MSC scaffolds seeded with MSCs, the scaffolds were filled with ALG hydrogel containing MSCs; acellular PHB/ALG and PHB/ALG filled with empty ALG hydrogel were prepared for comparison. The produced scaffolds have high porosity and irregular interconnected pore structure. PHB/HA scaffolds supported MSC growth and induced cell osteogenic differentiation in a regular medium in vitro that was manifested by an increase in ALP activity and expression of the CD45 phenotype marker. The data of computed tomography and histological studies showed 94% and 92%, respectively, regeneration of critical-sized calvarial bone defect in vivo at 28th day after implantation of MSC-seeded PHB/HA/ALG/MSC scaffolds with 3.6 times higher formation of the main amount of bone tissue at 22-28days in comparison with acellular PHB/HA/ALG scaffolds that was shown at the first time by fluorescent microscopy using the original technique of intraperitoneal administration of fluorescent dyes to living postoperative rats. The obtained in vivo results can be associated with the MSC-friendly microstructure and in vitro osteogenic properties of PHB/HA base-scaffolds. Thus, the obtained data demonstrate the potential of MSCs encapsulated in the bioactive biopolymer/mineral/hydrogel scaffold to improve the bone regeneration process in critical-sized bone defects.

Assessing the role of rainfall redirection techniques for arresting the land degradation under drip irrigated grapevines

Altering the soil surface features can potentially regulate water and solute movement processes in the soils, and reduce the accumulation of salts in the plant root zone. In this study, HYDRUS-2D was used consecutively for three years (2011–2014) to evaluate the potential impact of different rainfall redirection and water harvesting techniques such as no mounding or control (A), mid-row mounding (B), mid-row mounding covered with plastic (C), and plastic buried in the soil in mid-row (D) on water balance, root zone salinity dynamics, and salt balance in the soil in three grapevine producing regions (Loxton, McLaren Vale, and Padthaway) in South Australia. Simulations covered varied soil, climate, irrigation quality (0.3, 1.2, and 2.2 dS/m), and vine management conditions typical of each region. Seasonal transpiration (Tp), evaporation (Es), and drainage (Dr) accounted for 39–49, 26–44, and 17–25%, respectively, of the total drip irrigation applied to the vineyards across the three locations. Relative to the control, mounding mid-row soils (B) did not significantly alter the water balance at any site; adding an impermeable plastic layer to that mound (C) reduced Es (48–54%), and increased Dr (by two thirds) and Tp (1–16%). A tremendous ameliorative impact of mid-row mounding with plastic (C) was observed in the spatiotemporal salinity dynamics in the soils at all three locations (salt removal efficiency LEs > 1). An increased leaching fraction under the mid-row mounding with plastic (C) led to considerable (up to 14.6 t/ha) salts leaching from the crop root zone, which was double the other treatments. Buried plastic (D) showed slightly better outcomes than the control or mid-row mounding, particularly for seasonal salt leaching in heavy textured soils. Salt removal efficiency (LEs) > 1 in light- and medium-textured soils as compared to heavy-textured soils indicates better salt removal in the former soils. The results demonstrated that the mid-row mounding with plastic is an effective technique to reduce root zone salinity in the drip-irrigated horticultural crops.

Assessment of Water Quality and Soil Salinity in the Agricultural Coastal Plain (Ravenna, North Italy)

To improve knowledge on salt leaching suitability on different soils, in Arenosols and Cambisols croplands in the coastal area of Ravenna (Italy), soil samples were collected in the non-irrigation winter period and irrigation summer period. Concurrently, waters of the canal network were also investigated. Soil samples were analyzed for pH, carbonate, total organic carbon (TOC), particle size distribution, electrical conductivity (EC), bulk density (BD) and water content at field capacity (FC). Water samples were investigated for pH, EC, biological and chemical oxygen demand, sodium adsorption ratio, phosphorus, nitrogen, sulfates and chlorides. All soils had low TOC concentrations and Arenosols showed the lowest clay content, BD and FC. Soils had similar EC values in winter, but in summer the lowest ones were observed in Arenosols, suggesting that irrigation mitigated salinization in Arenosols, while the high clay content, BD and FC prevented or limited the salt leaching in Cambisols. In summer, the increase of total nitrogen and biological oxygen demand, especially in drainage channels, might suggest the leaching of soluble nutrients and organic matter from soils due to the high irrigation water volumes. Finally, our findings stress the need to consider soil type and properties to contrast soil salinization without negative effects on soil C leaching caused by salt leaching practice.

Coupled effects of biochar use and farming practice on physical properties of a salt-affected soil with wheat–maize rotation

Being carbon-rich and porous, biochar has the potential to improve soil physical properties, so does conventional farming practice. Here, a field trial was conducted to investigate the combined effects of biochar use and farming practice on the physical properties of a salt-affected compact soil for wheat–maize rotation in the Yellow River Delta region. Salix fragilis L. was used as feedstock to produce biochar in the field via aerobic carbonization at an average temperature of 502 °C, terminated by a water mist spray, for use as a soil amendment at 0, 1, 2, and 4 g kg−1 doses (CK, T1, T2, and T3, respectively). Farming practices included rotary tillage/straw returning for wheat sowing, spring irrigation, no-tillage seeding of maize, and autumn irrigation. Both cutting ring and composite samples of the soil were collected at four stages of wheat–maize rotation (22, 238, 321, and 382 d after the benchmark date of land preparation for wheat sowing) for the determination of soil properties by established methods. Rotary tillage/straw returning reduced soil bulk density (BD) from 1.48 to 1.27 g cm−3 (CK) and 1.14 g cm−3 (T3) and increased saturated hydraulic conductivity (Ks) from 0.05 × 10−5 to 0.75 × 10−5 cm s−1 (CK) and 1.25 × 10−5 cm s−1 (T3). This tillage effect on BD and Ks gradually disappeared due to the disturbance from the subsequent farming practice. Biochar use lessened the disturbance. At maize harvest, BD was 1.47 (CK) vs. 1.34 g cm−3 (T3), and Ks was 0.06 × 10−5 (CK) vs. 0.28 × 10−5 cm s−1(T3); in comparison with CK, T3 increased Na+ leaching by 65%, Cl− leaching by 98%, organic carbon content by 40.3%, and water-stable aggregates (0.25–2 mm) by 38%, indicating an improvement in soil properties. Biochar use and rotary tillage improved soil physical properties (BD, Ks) and favored soil aeration, water filtration, and salt leaching, which further helped the accumulation of soil organic carbon, the formation of water-stable aggregates, and the amelioration of salt-affected compact soil.

Changes in Soil Salinity at the Chervlenoe Irrigation Massive (Volgograd Oblast) in a Quarter of Century

Maps of soil salinity and toxic alkalinity in 2017–2018 were developed for the Chervlenoe irrigation massive of Svetloyarsk irrigation system. These maps were compared with the maps of soils in the virgin state and under irrigation in 1992 and 2006. The massive is located close to the Volga–Don Canal on the northern slopes of the Ergeni Upland (Volgograd oblast). Before irrigation, the soil cover was composed of associations (complexes) of loamy solonetzic light chestnut soils (Sodic Cambisols (Loamic, Ochric, Magnezic, Bathyprotosalilic)) and steppe solonetzes (Endosalic Solonetz (Albic, Loamic, Columnic, Cutanic, Differentic, Ochric, Magnezic)) developed from loesslike loam. The soil cover was strongly transformed by surface leveling during the irrigation system construction, and underwent secondary salinization in the 1970s–1990s because of excessive irrigation water supply. Changes in the soil salinity in the past 20–25 years are discussed. Both favorable (partial salt leaching) and negative (alkalization of topsoil horizons) processes are revealed.

Soil hydraulic model parameters and methodology as affected by sodium salt solutions

AbstractSoil salinization from shallow ground waters is problematic in numerous regions of the world. These ground waters can degrade soil physical properties and require special land management to maintain soil salinity levels ideal for crop and rangeland production. The objectives of this study were to evaluate how saline and sodic solutions changed soil hydrologic properties and how hydrologic parameters change with solution composition. Four soils ranging in texture from sandy loam to silty clay, were saturated with solutions ranging in electrical conductivities (EC) of 0.5 to 8 dS m−1 and sodium adsorption ratios (SAR) of 0 to 20. The hydraulic conductivity and water retention were measured using pressure plates, HYPROP evaporation method, and a dewpoint potentiometer. Data was fit with the van Genuchten and dual porosity models and the model parameters were evaluated. There was an increase in water retention and decrease in hydraulic conductivity when soils were near saturation as solution SAR increased and EC decreased at potentials near saturation. Water retention method combinations agreed well for low salinity treatments, but fitting parameters did not agree well for the higher salinity treatments. The coarser textured soil had a stronger disagreement in fitting parameters for the different water retention method combinations and greater salt build up near soil surface. Capillary rise of salt bearing waters of low EC and high SAR increases soil water retention and decreases hydraulic conductivity near saturation which will slow rates of downward water movement and salt leaching.

Water and salt exchange flux and mechanism in a dry saline soil amended with buried straw of varying thicknesses

Salt stress severely constrains crop productivity in arid lands of the world. Burying straw at the 40 cm soil depth plus plastic film mulching could mitigate root zone salinity, but little is known about how the thickness of buried straw affects soil water and salt transport. Therefore, a three-year field experiment was conducted from 2010 to 2013 to address this issue, with treatments including: compacted straw thickness of 3 cm (T3), 5 cm (T5), or 7 cm (T7) (corresponding to straw application at rates of 6, 12 and 18 t ha−1, respectively). In addition, a supplementary experiment, which included treatments of no buried straw layer (CK) and 5 cm of compacted straw layer thickness (t5) in the same micro-plot experiment, was carried out from 2014 to 2016 to identify soil pore structure and hydraulic parameters after three years of deep straw burial. Results showed that the initial soil water content increased with increasing thickness but significantly (P < 0.05) decreased in later periods. Soil salinity consistently decreased with increasing straw thickness, and T7 was most effective for improving salt leaching. However, the water and salt regulation under T5 gradually decreased mainly due to the change in saturated water conductivity and porosity among layers. After irrigation, the flux of salt leaching (FL) increased with straw thickness, and the FL under T7 significantly exceeded that under T3 by 105, 89 and 33% and that under T5 by 84, 66 and 33% in 2011, 2012 and 2013, respectively. The salt flux during evaporation under T7 was much higher (P < 0.05) than that under T3 and T5 by 92 and 10% in 2012 and 38, 44% in 2013. At harvest, salt storage within the soil consistently ranked as T3 > T5 > T7. Although T7 had the most pronounced effect on salt mitigation, it was difficult to implement under normal field conditions. Thus, for relatively good water infiltration, salt leaching and inhibition of salt return, straw buried to a thickness of 5 cm is recommended.

Small diameter blood vessels with controllable micropore structure induced by centrifugal force for improved endothelialization.

The micropore structure is prerequisite for fast and durable endothelialization of artificial small diameter blood vessels (ASDBVs). Although some methods, such as salt leaching, coagulation, and electrospinning, have been developed to construct micropores for ASDBVs, the uncontrollability of the structure and the complicated procedures of the process are still the issues to be concerned about. In this study, a compact device based on the principle of centrifugal force is established and used to prepare polyurethane (PU) ASDBVs with micropore structures by blasting different porogens. It is found that the glass beads could construct micropores with regular round shape, uniform distribution, and controllable size (60–350 µm), which significantly improves the endothelialization of PU‐based ASDBVs, especially when the pore size is about 60 µm. This method is easy‐accessible and wide‐applicable, which provides a new pathway for the research and development of ASDBVs.

Advances in the scaffolds fabrication techniques using biocompatible polymers and their biomedical application: A technical and statistical review

With the advancement in tissue engineering, researchers are working hard on new techniques to fabricate more advanced scaffolds from biocompatible polymers with enhanced porosity, appropriate mechanical strength, diverse shapes and sizes for potential applications in biomedical field in general and tissue engineering in particular. These techniques include electrospinning, solution blow spinning, centrifugal spinning, particulate leaching (salt leaching), freeze-drying, lithography, self-assembly, phase separation, gas foaming, melt molding, 3-D printing, fiber mesh and solvent casting. In this article we have summarized the scaffold’s fabrication techniques from biocompatible polymers that are reported so far, the recent advances in these techniques, characterization of the physicochemical properties of scaffolds and their potential applications in the biomedical field and tissue engineering. The article will help both newcomers and experts working in the biomedical implant fabrication to not only find their desired information in one document but also understand the fabrication techniques and the parameters that control the success of biocompatible polymeric scaffolds. Furthermore, a static analysis of the work published in all forms on the most innovative techniques is also presented. The data is taken from Scopus, restricting the search to biomedical fields and tissue engineering.

3D-composite scaffolds from radiation-induced chitosan grafted poly(3-hydroxybutyrate) polyurethane

Both chitosan (CS) and poly(3-hydroxybutyrate) (P(3HB)) are two good options for use in tissue engineering. Some of the advantages of these polymers are biodegradability and non-toxicity. However, the inadequate mechanical properties and hydrophobicity (P3HB) and the low porosity (CS) are examples of shortcomings that restrict its applications. The polysaccharide was grafted onto P(3HB) in a previous work for removing these disadvantages. As of yet, it is still unknown whether our P(3HB)-g-CS has potential as an interface with biological systems. This work aimed to use the gamma radiation-induced grafted CS to prepare a polyurethane composite scaffold with silica nanoparticles obtained from vermicomposting and porosity induced by salt leaching. The obtained structural and morphological characterization, interconnectivity, degree of porosity and swelling, mechanical and morphometrical properties (μ-CT) showed that the new poly(saccharide-ester-urethane) composite properties are suitable for cell culture. The poly(urethane-urea) composites did not induce cytotoxic effects. Viability assays proved that it efficiently allows the three-dimensional culturing of pancreatic islet cells.

Simulation of the Effect of Climate Variability on Reclamation Success of Brine-Affected Soil in Semi-Arid Environments

Soils in arid and semi-arid environments are threatened by salinization. A cost-effective and efficient way to reclaim saline land is through leaching. This will be most effective in situations where direct human impact is the cause for salinity, e.g., in environments affected by industrial use or land rehabilitation following mining. Irrigation, which is the most common means of achieving salt leaching, is not feasible for the reclamation of mine sites’ salt-affected soils located in remote areas, and thus, land reclamation largely relies on natural climatic conditions. This study was conducted to assess the effect of different climatic conditions of semi-arid environments on spatio-temporal salt leaching from brine-affected soil, and investigate the efficacy of the reduction of soil bulk density as a reclamation technique for saline land experiencing water scarcity. Three regions (represented by the Australian cities of Roma, Mount Isa, and Quilpie) representing semi-arid environments of Australia were selected, and their climatic scenarios (23 years) were applied to a validated HYDRUS-1D model. A brine-affected soil typical to Queensland, Australia, was chosen for this study. The investigations established that a greater number of individual high rainfall events resulted in a greater reduction of salinity in Roma (96%) and Mount Isa (93.31%) compared with Quilpie (58.75%), in which the soil salinity approached a level (&lt;2 dS m−1) that was suitable for sustaining plant growth. Soil salinity reduced to 8 dS m−1 under the climatic conditions of the Quilpie region. This study also demonstrated that the success of salt leaching from a brine-affected soil is a consequence of a sensitive response to the depth of individual rainfall events rather than rainfall distribution and the total amount of rainfall, and is controlled by the physical properties of the soil. Where climatic conditions cannot solely assist with salt leaching, reclamation may be successful by reducing soil bulk density.