Three-Pond Model with Fuzzy Inference System-Based Water Level Regulation Scheme for Run-of-River Hydropower Plant

Power generation from river hydropower plants depends mainly on river flow. Water fluctuations in the river make the yield process unpredictable. To reduce these fluctuations, building a small reservoir at the river flow of the hydropower plant is recommended. Conventionally, classic single-pond models are commonly used to design run-of-river hydropower plants. However, such models are associated with fluctuations, sagging, and irregular power fluctuations that lead to irregular water fluctuations. This research proposes a novel idea to replace the single-pond model with a three-pond model to increase the plant’s overall efficiency. The three-pond model is developed as a three-tank nonlinear hydraulic system that contains the same amount of water as a conventional single pond. It also has the advantage of minimizing the run-of-river power plant’s dependence on river flow and increasing efficiency by trapping swell and turbulence in the water. To further increase the efficiency, the developed model was tested for smooth and effective level control using fuzzy control.publishedVersionPeer reviewe

Sodium alginate-f-GO composite hydrogels for tissue regeneration and antitumor applications

Biopolymer-based composite hydrogels have attracted tremendous attention for tissue regeneration and antitumor applications. Since sodium alginate is a biopolymer, they offer excellent therapeutic options with long-term drug release and low side effects. To prepare multifunctional composite hydrogels with anticancer and tissue regeneration capabilities, sodium alginate (SA) and graphene oxide (GO) were covalently linked and crosslinked with tetraethyl orthosilicate (TEOS) by the solvothermal method. The structural and morphological results show that the hydrogels exhibit the desired functionality and porosity. The swelling of hydrogels in an aqueous and PBS medium was investigated. SGT-4 had the highest swelling in both aqueous and PBS media. Swelling and biodegradation of the hydrogel were inversely related. The drug release of SGT-4 was determined in different pH media (pH 6.4, 7.4, and 8.4) and the kinetics of drug release was determined according to the Higuchi model (R2 = 0.93587). Antibacterial activities were evaluated against severe infectious agents. Uppsala (U87) and osteoblast (MC3T3-E1) cell lines were used to determine the anticancer and biocompatibility of the composite hydrogels, respectively. These results suggest that the composite hydrogels could be used as potential biomaterials for tissue regeneration and antitumor applications

Antibacterial and hemocompatible pH-responsive hydrogel for skin wound healing application: in vitro drug release

The treatment of successive skin wounds necessitates meticulous medical procedures. In the care and treatment of skin wounds, hydrogels produced from natural polymers with controlled drug release play a crucial role. Arabinoxylan is a well-known and widely available biological macromolecule. We produced various formulations of blended composite hydrogels (BCHs) from arabinoxylan (ARX), carrageenan (CG), and reduced graphene oxide (rGO) using and cross-linked them with an optimal amount of tetraethyl orthosilicate (TEOS). The structural, morphological, and mechanical behavior of the BCHs samples were determined using Fourier-transform infrared spec-troscopy (FT-IR), Scanning electron microscope (SEM), mechanical testing, and wetting, respectively. The swelling and degradation assays were performed in phosphate-buffered saline (PBS) solution and aqueous media. Maximum swelling was observed at pH 7 and the least swelling in basic pH regions. All composite hydrogels were found to be hemocompatible. In vitro, silver sulfadiazine release profile in PBS solution was analyzed via the Franz diffusion method, and maximum drug release (87.9%) was observed in 48 h. The drug release kinetics was studied against different mathematical models (zero-order, first-order, Higuchi, Hixson–Crowell, Korsmeyer–Peppas, and Baker–Lonsdale models) and compared their regression coefficient (R2) values. It was observed that drug release follows the Baker–Lonsdale model, as it has the highest value (0.989) of R2. Hence, the obtained results indicated that, due to optimized swelling, wetting, and degradation, the blended composite hydrogel BCH-3 could be an essential wound dressing biomaterial for sustained drug release for skin wound care and treatment

Role of Graphene Oxide in Bacterial Cellulose−Gelatin Hydrogels for Wound Dressing Applications

Biopolymer-based hydrogels have several advantages, including robust mechanical, high biocompatibility, and excellent properties. These hydrogels can be ideal wound dressing materials and advantageous to repair and regenerate skin wounds. In this work, we have reported fabricated of composite hydrogels from gelatin and graphene oxide-functionalized-bacterial cellulose (synthesized by hydrothermal method) (GO-f-BC) and crosslinked with tetraethyl orthosilicate (TEOS). The hydrogels were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscopy, and water contact angle analyses to explore functional groups and their interactions, surface morphology, and wetting behavior, respectively. The swelling, biodegradation, and water retention were tested to respond to biofluid. Maximum swelling was exhibited by samle with maximum amount of GO (GBG-4) in all media (aqueous = 1902.83%, PBS = 1546.63%, and electrolyte = 1367.32%). The hemolysis of all hydrogel samples is less than 0.5%, and the blood coagulation time decreased as the hydrogel concentration increased. The composite hydrogels were found to be hemocompatible as they have less than 0.5% hemolysis for all hydrogel samples under in vitro standard conditions. These hydrogels performed unusual antimicrobial activities against Gram (positive and negative) bacterial strains. The cell viability and proliferation were increased with an increased GO amount, and maximum values were found for GBG-4 against fibroblast (3T3) cell lines. The mature and well-adhered cell morphology of 3T3 cells was found against all hydrogel samples. Hence, based on these results findings, these hydrogels would be potential wound dressing skin materials for wound healing applications.We are grateful to the European Union's Horizon to support the research project. This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement no. 951747 and acknowledge the NPRP award [NPRP 12S -0310-190276] from the Qatar National Research Fund (a member of The Qatar Foundation). The statements made herein are solely the responsibility of the authors.Scopu

Synthesis of silver-coated bioactive nanocomposite scaffolds based on grafted beta- glucan/hydroxyapatite via freeze-drying method: anti-microbial and biocompatibility evaluation for bone tissue engineering

Advancement and development in bone tissue engineering, particularly that of composite scaffolds, are of great importance for bone tissue engineering. We have synthesized polymeric matrix using biopolymer (β-glucan), acrylic acid, and nano-hydroxyapatite through free radical polymerization method. Bioactive nanocomposite scaffolds (BNSs) were fabricated using the freeze-drying method and Ag was coated by the dip-coating method. The scaffolds have been characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction analysis (XRD) to investigate their functional groups, surface morphology, and phase analysis, respectively. The pore size and porosity of all BNS samples were found to be dependent on silver concentration. Mechanical testing of all BNS samples have substantial compressive strength in dry form that is closer to cancellous bone. The samples of BNS showed substantial antibacterial effect against DH5 alpha E. coli. The biological studies conducted using the MC3T3-E1 cell line via neutral red dye assay on the scaffolds have found to be biocompatible and non-cytotoxic. These bioactive scaffolds can bring numerous applications for bone tissue repairs and regenerations

Underutilized Grasses Production: New Evolving Perspectives

Globally, over-reliance on major food crops (wheat, rice and maize) has led to food basket’s shrinking, while climate change, environmental pollution and deteriorating soil fertility demand the cultivation of less exhaustive but nutritious grasses. Unlike neglected grasses (grass species restricted to their centres of origin and only grown at the subsistence level), many underutilized grasses (grass species whose yield or usability potential remains unrealized) are resistant and resilient to abiotic stresses and have multiple uses including food (Coix lacryma-jobi), feed (Eragrostis amabilis and Cynodon dactylon), esthetic value (Miscanthus sinensis and Imperata cylindrica), renewable energy production (Spartina pectinata and Andropogon gerardii Vitman) and contribution to ecosystem services (Saccharum spontaneum). Lack of agricultural market globalization, urbanization and prevalence of large commercial enterprises that favor major grasses trade, improved communication means that promoted specialization in favor of established crops, scant planting material of underutilized grasses and fewer research on their production technology and products development are the prime challenges posed to underutilized grasses promotion. Integration of agronomic research with novel plant protection measures and plant breeding and molecular genetics approaches for developing biotic and abiotic stresses tolerant cultivars along with the development of commercially attractive food products hold the future key for promoting underutilized grasses for supplanting food security and sustainably multiplying economic outcomes

Chitosan/poly vinyl alcohol/graphene oxide based ph-responsive composite hydrogel films: drug release, anti-microbial and cell viability studies

The composite hydrogels were produced using the solution casting method due to the non-toxic and biocompatible nature of chitosan (CS)/polyvinyl alcohol (PVA). The best composition was chosen and crosslinked with tetraethyl orthosilicate (TEOS), after which different amounts of graphene oxide (GO) were added to develop composite hydrogels. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle was used to analyze the hydrogels. The samples were also evaluated for swelling abilities in various mediums. The drug release profile was studied in phosphate-buffered saline (PBS) at a pH of 7.4. To predict the mechanism of drug release, the data were fitted into kinetic models. Finally, antibacterial activity and cell viability data were obtained. FTIR studies revealed the successful synthesis of CS/PVA hydrogels and GO/CS/PVA in hydrogel composite. SEM showed no phase separation of the polymers, whereas AFM showed a decrease in surface roughness with an increase in GO content. 100 µL of crosslinker was the critical concentration at which the sample displayed excellent swelling and preserved its structure. Both the crosslinked and composite hydrogel showed good swelling. The most acceptable mechanism of drug release is diffusion-controlled, and it obeys Fick’s law of diffusion for drug released. The best fitting of the zero-order, Hixson-Crowell and Higuchi models supported our assumption. The GO/CS/PVA hydrogel composite showed better antibacterial and cell viability behaviors. They can be better biomaterials in biomedical applications

Characterization of titanium ceramic composite for bone implants applications

Bone implants are widely used to restore bone loss due to several factors including but not limited to osteoporosis, osteoarthritis and road injuries. Current bone implant materials restore mechanical stability but suffer from a lack of osteointegration and will need to be replaced after long term use. To circumvent this, tissue engineering which capitalizes on the use of cells, biochemical factors and biodegradable materials aim to develop a biological substitute that restores, maintain or improve tissue functions. Central to the improvement of the tissue function and its stability through the implant relies on its interaction with the host tissue. Hence, a bioactive implant that promotes osteointegration is more desirable than an inert implant. In this study, metal-ceramic composites are explored for their suitability to be used as bone implants in the future. Fabrication of the composite was optimized using hot press compression and vacuum sintering method. Data presented include physicochemical characteristics of titanium-hydroxyapatite and titanium-wollastonite analyzed via SEM, FTIR, XRD, 3D laser microscopy and mechanical test. Evidence of material biocompatibility with primary human osteoprogenitor cells is also provided. Both titanium hydroxyapatite and titanium wollastonite possess the potential as the future of metal-ceramic composites as they possess the bioactivity of ceramic while still maintaining its core titanium body as a source of strength

Development of antibacterial, degradable and pH-responsive chitosan/guar gum/polyvinyl alcohol blended hydrogels for wound dressing

The present research is based on the fabrication preparation of CS/PVA/GG blended hydrogel with nontoxic tetra orthosilicate (TEOS) for sustained paracetamol release. Different TEOS percentages were used because of their nontoxic behavior to study newly designed hydrogels’ crosslinking and physicochemical properties. These hydrogels were characterized using Fourier-transform infrared spec-troscopy (FTIR), scanning electron microscopy (SEM), and wetting to determine the functional, surface morphology, hydrophilic, or hydrophobic properties. The swelling analysis in different media, degradation in PBS, and drug release kinetics were conducted to observe their response against corresponding media. The FTIR analysis confirmed the components added and crosslinking between them, and surface morphology confirmed different surface and wetting behavior due to different crosslinking. In various solvents, including water, buffer, and electrolyte solutions, the swelling behaviour of hydrogel was investigated and observed that TEOS amount caused less hydrogel swelling. In acidic pH, hydrogels swell the most, while they swell the least at pH 7 or higher. These hydrogels are pH-sensitive and appropriate for controlled drug release. These hydrogels demonstrated that, as the ionic concentration was increased, swelling decreased due to decreased osmotic pressure in various electrolyte solutions. The antimicrobial analysis revealed that these hydrogels are highly antibacterial against Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram negative (Pseudomonas aeruginosa and Escherichia coli) bacterial strains. The drug release mechanism was 98% in phosphate buffer saline (PBS) media at pH 7.4 in 140 min. To analyze drug release behaviour, the drug release kinetics was assessed against different mathematical models (such as zero and first order, Higuchi, Baker–Lonsdale, Hixson, and Peppas). It was found that hydrogel (CPG2) follows the Peppas model with the highest value of regression (R2 = 0.98509). Hence, from the results, these hydrogels could be a potential biomaterial for wound dressing in biomedical applications