MXene-Based Flexible Electrodes for Electrophysiological Monitoring.

The advancement of flexible electrodes triggered research on wearables and health monitoring applications. Metal-based bioelectrodes encounter low mechanical strength and skin discomfort at the electrode-skin interface. Thus, recent research has focused on the development of flexible surface electrodes with low electrochemical resistance and high conductivity. This study investigated the development of a novel, flexible, surface electrode based on a MXene/polydimethylsiloxane (PDMS)/glycerol composite. MXenes offer the benefit of featuring highly conductive transition metals with metallic properties, including a group of carbides, nitrides, and carbonitrides, while PDMS exhibits inherent biostability, flexibility, and biocompatibility. Among the various MXene-based electrode compositions prepared in this work, those composed of 15% and 20% MXene content were further evaluated for their potential in electrophysiological sensing applications. The samples underwent a range of characterization techniques, including electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), as well as mechanical and bio-signal sensing from the skin. The experimental findings indicated that the compositions demonstrated favorable bulk impedances of 280 and 111 Ω, along with conductivities of 0.462 and 1.533 mS/cm, respectively. Additionally, they displayed promising electrochemical stability, featuring charge storage densities of 0.665 mC/cm2 and 1.99 mC/cm2, respectively. By conducting mechanical tests, Young's moduli were determined to be 2.61 MPa and 2.18 MPa, respectively. The composite samples exhibited elongation of 139% and 144%, respectively. Thus, MXene-based bioelectrodes show promising potential for flexible and wearable electronics and bio-signal sensing applications.

MXenes and MXene-based materials for removal of pharmaceutical compounds from wastewater: Critical review.

The rapid increase in the global population and its ever-rising standards of living are imposing a huge burden on global resources. Apart from the rising energy needs, the demand for freshwater is correspondingly increasing. A population of around 3.8 billion people will face water scarcity by 2030, as per the reports of the World Water Council. This may be due to global climate change and the deficiency in the treatment of wastewater. Conventional wastewater treatment technologies fail to completely remove several emerging contaminants, especially those containing pharmaceutical compounds. Hence, leading to an increase in the concentration of harmful chemicals in the human food chain and the proliferation of several diseases. MXenes are transition metal carbide/nitride ceramics that primarily structure the leading 2D material group. MXenes act as novel nanomaterials for wastewater treatment due to their high surface area, excellent adsorption properties, and unique physicochemical properties, such as high electrical conductivity and hydrophilicity. MXenes are highly hydrophilic and covered with active functional groups (i.e., hydroxyl, oxygen, fluorine, etc.), which makes them efficient adsorbents for a wide range of species and promising candidates for environmental remediation and water treatment. This work concludes that the scaling up process of MXene-based materials for water treatment is currently of high cost. The up-to-date applications are still limited because MXenes are currently produced mainly in the laboratory with limited yield. It is recommended to direct research efforts towards lower synthesis cost procedures coupled with the use of more environmentally friendly materials to avoid secondary contamination.

Removal of ciprofloxacin antibiotic pollutants from wastewater using nano-composite adsorptive membranes.

The emergence of antibiotics in water has been globally recognized as a critical pollution issue. Antibiotics (such as Ciprofloxacin (CPFX) pose a serious threat to humans and to the ecosystem due to its accumulation in water sources which can lead to chronic health problems and endanger aquatic life. It is therefore crucial to properly remove them from water. In this work, a nano-composite adsorptive membrane based on Zirconium Phosphate (ZrP) adsorbent supported on Polyethersulfone (PES) was synthesized and evaluated for the removal of CPFX from synthetic aqueous solutions. The membranes described here showed a very high antibiotic removal rate. The effect of various parameters such as the initial concentration of the antibiotic, the adsorbent dosage, contact time, pH, and temperature was studied. The equilibrium data were found to reasonably best fit with the Temkin isotherm model. The membranes showed a high ciprofloxacin removal (99.7%) as opposed to (68%) when PES membrane alone was used. Moreover, a significant improvement in the membrane's water flux (100.84 L/m2.h) and permeability (97.62 L/m2.hr.bar) were noticed as opposed to pure PES membrane's flux and permeability. The adsorptive membranes were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET). The results confirmed the successful formation of ZrP nanoparticles adsorbent within the membrane matrix, and with enhanced hydrophilic properties. The membrane was successfully regenerated and reused up to 5 times. The results of this work showed the potential of such membranes for the removal of ciprofloxacin and at a high efficiency.

The surfactant-ionic liquid bi-functionalization of chitosan beads for their adsorption performance improvement toward Tartrazine.

In this study, the ionic liquid (Aliquat-336) and anionic surfactant (cetyltrimethylammonium bromide, CTAB) bi-functionalized chitosan beads were prepared and characterised using different techniques, including FTIR, XRD, SEM, EDS and BET surface area analysis. The characteristic analysis confirmed the successful conjugation of chitosan beads with both surfactant and ionic liquid. The novel fabricated beads (CS-CTAB-AL) were efficiently employed, as a high-performance adsorbent, for the removal of Tartrazine (TZ), an anionic food dye, from polluted water. The optimum adsorption of TZ onto the CS-CTAB-AL was found at 2 g L-1 of adsorbent in the wide pH range of 4-11, whereas just 45 min was required to reach more than 90% adsorption efficiency in the studied conditions. Also, the adsorption and kinetic studies showed that the experimental data well fitted the pseudo-first-order kinetic model and the Langmuir isotherm model. The maximum adsorption capacity of prepared beads was found to be 45.95 mg g-1 at 45 °C. The adsorption properties of enabling CS-CTAB-AL conjugation introduced a new type of adsorbents, exploited the combination of ionic liquid and surfactant capabilities for wastewater treatment.

Biodegradable polymers and their nano-composites for the removal of endocrine-disrupting chemicals (EDCs) from wastewater: A review.

Endocrine-disrupting chemicals (EDCs) target the endocrine system by interfering with the natural hormones in the body leading to adverse effects on human and animal health. These chemicals have been identified as major polluting agents in wastewater effluents. Pharmaceuticals, personal care products, industrial compounds, pesticides, dyes, and heavy metals are examples of substances that could be considered endocrine active chemicals. In humans, these chemicals could cause obesity, cancer, Alzheimer's disease, autism, reproductive abnormalities, and thyroid problems. While in wildlife, dysfunctional gene expression could lead to the feminization of some aquatic organisms, metabolic diseases, cardiovascular risk, and problems in the reproductive system as well as its levels of hatchability and vitellogenin. EDCs could be effectively removed from wastewater using advanced technologies such as reverse osmosis, membrane treatment, ozonation, advanced oxidation, filtration, and biodegradation. However, adsorption has been proposed as a more promising and sustainable method for water treatment than any other reported technique. Increased attention has been paid to biodegradable polymers and their nano-composites as promising adsorbents for the removal of EDCs from wastewater. These polymers could be either natural, synthetic, or a combination of both. This review presents a summary of the most relevant cases where natural and synthetic biodegradable polymers have been used for the successful removal of EDCs from wastewater. It demonstrates the effectiveness of these polymers as favorable adsorbents for novel wastewater treatment technologies. Hitherto, very limited work has been published on the use of both natural and synthetic biodegradable polymers to remove EDCs from wastewater, as most of the studies focused on the utilization of only one type, either natural or synthetic. Therefore, this review could pave the way for future exploration of biodegradable polymers as promising and sustainable adsorbents for the removal of various types of pollutants from wastewater.

A critical review on metal-based catalysts used in the pyrolysis of lignocellulosic biomass materials.

This review discusses the technical aspects of improving the efficiency of the pyrolysis of lignocellulosic materials to increase the yield of the main products, which are bio-oil, biochar, and syngas. The latest aspects of catalyst development in the biomass pyrolysis process are presented focusing on the various catalyst structures, the physical and chemical performance of the catalysts, and the mode of the catalytic reaction. In bio-oil upgrading, atmospheric catalytic cracking is shown to be more economical than catalytic hydrotreating. Catalysts help in the upgrading process by facilitating several reaction pathways such as polymerization, aromatization, and alkyl condensation. However, the grade of bio-oil must be similar to that of diesel fuel. Hence, the properties of the pyrolysis liquid such as viscosity, kinematic viscosity, density, and boiling point are important and have been highlighted. Switching between types of catalysts has a significant influence on the final product yields and exhibits different levels of durability. Various catalysts have been shown to enhance gas yield at the expense of the yields of bio-oil and biochar that shift the overall purpose of pyrolysis. Therefore, the catalytic activity as a function of temperature, pressure, and catalyst biomass ratio is discussed in detail. These operational parameters are crucial because they determine the overall yield as well as the ratio of the oil, char, and gas products. Although significant progress has been made in catalytic pyrolysis, the economic feasibility of the process and the catalyst cost remain the major obstacles. This review concludes that the catalytic process would be feasible when the fuel selling price is reduced to less than US $ 4 per gallon of gasoline-equivalent, and when the selectivity of catalysts is further enhanced.

A Comparative Assessment of Arsenic Risks and the Nutritional Benefits of Fish Consumption in Kuwait: Arsenic Versus Omega 3-Fatty Acids.

Inorganic and organic forms of arsenic (As), as well as omega-3 fatty acids were measured in 578 fish/seafood samples that belong to 15 species of commonly consumed seafood in Kuwait. Arsenic speciation data, with the toxicological profile of inorganic arsenic (iAs) and fish consumption rates were applied in a probabilistic risk assessment to estimate the risk from exposure to iAs. The nutritional benefits of omega-3-fatty acid levels in various species of fish were taken into consideration. Results showed that the mean daily intake of iAs through fish consumption among the Kuwaiti population was 0.058 µg/kg/day, and the 95th percentile was 0.15 µg/kg/day. Although the mean intake level did not exceed the incremental lifetime cancer risk (ILCR) at 1 × 10-4, the 95th percentile of iAs intake showed an ILCR of 2.7 × 10-4. Kuwaiti children (aged 6-12 years) were found to have a higher mean intake of iAs at 0.10 µg/kg/day with 68% of children in this category, exceeding the risk specific dose associated with an ILCR of 1 × 10-4. The fish species, hammor (grouper; Epinephelus coioides), is the top contributor to iAs intake, and tuna is the major source of omega 3-fatty acids for the Kuwaiti population.

Total body water measurement using the 2H dilution technique for the assessment of body composition of Kuwaiti children.

OBJECTIVE: The 2H dilution technique is the reference method to estimate total body water for body composition assessment. The aims of the present study were to establish the total body water technique at the Kuwait Institute for Scientific Research and assess body composition of Kuwaiti children. DESIGN: The isotope ratio mass spectrometer was calibrated with defined international reference water standards. A non-random sampling approach was used to recruit a convenience sample of Kuwaiti children. A dose of 2H2O, 1-3 g, was consumed after an overnight fast and 2H enrichment in baseline and post-dose urine samples was measured. Total body water was calculated and used to estimate fat-free mass. Fat mass was estimated as body weight minus fat-free mass. SETTING: The total body water study was implemented in primary schools. SUBJECTS: Seventy-five boys and eighty-three girls (7-9 years). RESULTS: Measurements of the isotope ratio mass spectrometer were confirmed to be accurate and precise. Children were classified as normal weight, overweight or obese according to the WHO based on BMI-for-age Z-scores. Normal-weight and overweight girls had significantly higher percentage body fat (median (range): 32·4 % (24·7-39·3 %) and 38·3 % (29·3-44·2 %), respectively) compared with boys (median (range): 26·5 % (14·2-37·1 %) and 34·6 % (29·9-40·2 %), respectively). No gender difference was found in obese children (median 46·5 % v. 45·6 %). CONCLUSIONS: The establishment of a state-of-the-art stable isotope laboratory for assessment of body composition provides an opportunity to explore a wide range of applications to better understand the relationship between body size, body composition and risk of developing non-communicable diseases in Kuwait.

Nanogel-based composites for bacterial antibiofilm activity: advances, challenges, and prospects.

Nano-based approaches, particularly nanogels, have recently emerged as a potential strategy for combating biofilm-related infections. Their exceptional characteristics including biocompatibility, biodegradability, stability, high water content, stimuli-responsiveness, and their nano size (which enables their penetration into biofilms) make nanogels a promising technology in the biomedical field. However, exploring nanogels for biofilm treatment remains in its early stages. This review examined the status of nanogels application for the treatment of bacterial biofilms. Recent investigations studied nanogels derived from natural polymers like chitosan (CS), hyaluronic acid (HA), and alginate, among others, for eliminating and inhibiting biofilms. These nanogels were utilized as carriers for diverse antibiofilm agents, encompassing antibiotics, antimicrobial peptides, natural extracts, and nanoparticles. Utilizing mechanisms like conventional antibody-mediated pathways, photodynamic therapy, photothermal therapy, chemodynamic therapy, and EPS degradation, these nanogels effectively administered antibiofilm drugs, exhibiting efficacy across several bacterial strains, notably Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), and Escherichia coli (E. coli), among others. Despite showing promise, nanogels remain relatively underexplored in biofilm treatment. This review concludes that research gaps are still present in biofilm treatment processes including (i) a better understanding of the stimuli-responsive behaviors of nanogels, (ii) active targeting strategies, and (iii) the narrow spectrum of antibiofilm agents loaded into nanogels. Hence, future studies could be directed towards the following elements: the exploration of multi-strain biofilms rather than single-strain biofilms, other endogenous and exogenous stimuli to trigger drug release, active targeting mechanisms, a broader range of antibiofilm agents when employing nanogels, and fostering more comprehensive and reliable biofilm treatment strategies. This review found that there are currently several research gaps as well in the use of nanogels for biofilm therapy, and these include: (i) very limited exogenous and endogenous stimuli were explored to trigger drug release from nanogels, (ii) the active targeting strategies were not explored, (iii) a very narrow spectrum of antibiofilm agents was loaded into nanogels, and (iv) only biofilms of single strains were investigated.

Evidence for nutrition transition in Kuwait: over-consumption of macronutrients and obesity.

OBJECTIVES: To describe nutrient intakes and prevalence of overweight and obesity in a nationally representative sample of Kuwaitis and to compare intakes with reference values. DESIGN: Cross-sectional, multistage stratified, cluster sample. Settings National nutrition survey covering all geographical areas of the country. SUBJECTS: Kuwaitis (n 1704) between 3 and 86 years of age. RESULTS: Obesity was more prevalent among women than men (50 % and 70 % for females aged 19-50 years and ≥51 years, respectively, v. 29 % and 42 % for their male counterparts). Boys were more obese than girls, with the highest obesity rate among those aged 9-13 years (37 % and 24 % of males and females, respectively). Energy intake was higher than the estimated energy requirements for almost half of Kuwaiti children and one-third of adults. The Estimated Average Requirement was exceeded by 78-100 % of the recommendation for protein and carbohydrates. More than two-thirds of males aged ≥4 years exceeded the Tolerable Upper Intake Level for Na. Conversely, less than 20 % of Kuwaitis, regardless of age, consumed 100 % or more of the Estimated Average Requirement for vitamin D, vitamin E, Ca, n-3 and n-6 fatty acids. Less than 20 % of children met the recommended level for fibre. CONCLUSIONS: Nutrition transition among Kuwaitis was demonstrated by the increased prevalence of obesity and overweight, increased intakes of energy and macronutrients and decreased intakes of fibre and micronutrients. Interventions to increase awareness about healthy foods combined with modifications in subsidy policies are clearly warranted to increase consumption of low-energy, nutrient-dense foods.

A Flexible Conductive Electrode Using Boronic-Acid Modified Carbon Dots.

Flexible electrodes are becoming a topic of interest for a range of applications including implantation. They can be used for neural signal recording and for electrical stimulation of atrophying muscles. Unlike the traditionally used metal electrodes that are harsh to the body's tissues, flexible electrodes conduct electricity while preserving the delicate tissues. Polydimethylsiloxane (PDMS), a non-conductive synthetic polymer characterized by its flexibility, low cost, biocompatibility, and durability during implantation, has been explored as a matrix for flexible electrodes. This study reports the synthesis of composite boronic acid-modified carbon dots (BA-CDs)/PDMS electrode materials. The performance of the composite electrode is evaluated electrochemically (for its conductivity and charge storage capacity) and mechanically (Young's modulus). Furthermore, the effect of increasing the PDMS crosslinking density on the electrode's performance is studied based on the hypothesis that a higher crosslinking will bring the BA-CDs closer together, thereby facilitating the movement of electrons. Results of this study showed that incorporating 10% BA-CDs dispersed with 16% glycerol in 74% PDMS with a higher crosslinking density resulted in a bulk impedance of 47.7 Ω and a conductivity of 2.68×10-3 S/cm, both of which surpassed that of the same composition with lower crosslinking. The synthesized flexible electrode material was capable of charge storage although the charge storage capacity (0.00365 mC/cm2) was lower than the safe limit for some tissue activation. Furthermore, the electrode maintained a modulus of elasticity (0.2322 MPa) that is compatible with biological soft tissues.Clinical Relevance- This study reports a conductive electrode that has a flexibility compatible with that of biological tissues for future purposes such as neural signal recording and tissue electrical stimulation (e.g. atrophying muscles). The reported BA-CD/PDMS electrode overcomes the limitations of the harsh metals previously used as implantable electrodes that harm the biological tissues due to their high rigidity.

Desulfurization of Diesel Using Ionic Liquids: Process Design and Optimization Using COSMO-Based Models and Aspen Plus.

Sulfur dioxide emissions from fossil fuel combustion have been known to cause detrimental health and environmental effects. The currently used hydrodesulfurization (HDS) method employed by refineries has several drawbacks, such as excessive hydrogen consumption, high energy demand, and inability to remove complex organosulfur compounds, which have limited its ability to produce ultralow sulfur diesel (ULSD) at reasonable operating and capital costs. Ionic liquids (ILs) have been widely studied for their potential to replace conventional HDS. However, while their success has been demonstrated at the laboratory level, studies on industrial-scale feasibility and their integration into process simulators such as Aspen Plus are limited. In this work, 26 commercially available ILs have been screened using COSMO-based models and Aspen Plus for the desulfurization of diesel fuel and several possible process configurations have been examined. In particular, the challenge of ionic liquid regeneration, which has largely been ignored in the literature, has also been addressed and several potential regeneration methods have been proposed including extractive regeneration (E-RE) and stripping regeneration using nitrogen and air as stripping media (S-RE). The results indicate that, among the 26 ILs studied, 1-butyl-3-methylimidazolium thiocyanate is the most promising as a solvent for extractive desulfurization (EDS), E-RE, and S-RE. E-RE was found to be more effective for the removal of dibenzothiophene (DBT), while S-RE is more suited to the removal of thiophene and benzothiophene (BT). As a result, an optimized diesel desulfurization process using 1-butyl-3-methylimidazolium thiocyanate has been proposed that achieves ULSD with <10 ppm total sulfur in simulation studies, with complete recycling of the IL and minimal loss of the model diesel.

A Critical Review on the Use of Ionic Liquids in Proton Exchange Membrane Fuel Cells.

This work provides a comprehensive review on the incorporation of ionic liquid (ILs) into polymer blends and their utilization as proton exchanges membranes (PEM). Various conventional polymers that incorporate ILs are discussed, such as Nafion, poly (vinylidene fluoride), polybenzimidazole, sulfonated poly (ether ether ketone), and sulfonated polyimide. The methods of synthesis of IL/polymer composite membranes are summarized and the role of ionic liquids as electrolytes and structure directing agents in PEM fuel cells (PEMFCs) is presented. In addition, the obstacles that are reported to impede the development of commercial polymerized IL membranes are highlighted in this work. The paper concludes that the presence of certain ILs can increase the conductivity of the PEM, and consequently, enhance the performance of PEMFCs. Nevertheless, the leakage of ILs from composite membranes as well as the limited long-term thermal and mechanical stability are considered as the main challenges that limit the employment of IL/polymer composite membranes in PEMFCs, especially for high-temperature applications.

Multifunctional stimuli-responsive hybrid nanogels for cancer therapy: Current status and challenges.

With cancer research shifting focus to achieving multifunctionality in cancer treatment strategies, hybrid nanogels are making a rapid rise to the spotlight as novel, multifunctional, stimuli-responsive, and biocompatible cancer therapeutic strategies. They can possess cancer cell-specific cytotoxic effects themselves, carry drugs or enzymes that can produce cytotoxic effects, improve imaging modalities, and target tumor cells over normal cells. Hybrid nanogels bring together a wide range of desirable properties for cancer treatment such as stimuli-responsiveness, efficient loading and protection of molecules such as drugs or enzymes, and effective crossing of cellular barriers among other properties. Despite their promising abilities, hybrid nanogels are still far from being used in the clinic, and their available data remains relatively limited. However, many studies can be done to facilitate this clinical transition. This review is critically summarizing and analyzing the recent information and progress on the use of hybrid nanogels particularly inorganic nanoparticle-based and organic nanoparticle-based hybrid nanogels in the field of oncology and future directions to aid in transferring those results to the clinic. This work concludes that the future of hybrid nanogels is greatly impacted by therapeutic and non-therapeutic factors. Therapeutic factors include the lack of hemocompatibility studies, acute and chronic toxicological studies, and information on agglomeration capability and extent, tumor heterogeneity, interaction with proteins in physiological fluids, endocytosis-exocytosis, and toxicity of the nanogels' breakdown products. Non-therapeutic factors include the lack of clear regulatory guidelines and standardized assays, limitations of animal models, and difficulties associated with good manufacture practices (GMP).

Novel enzymatic graphene oxide based biosensor for the detection of glutathione in biological body fluids.

In this work, we report a novel enzymatic biosensor based on glutathione peroxidase (GSH-Px), graphene oxide (GO) and nafion for the electrochemical sensing of glutathione (GSH) in body fluids. GSH-Px was immobilized covalently via 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) onto modified glassy carbon electrode (GCE) decorated with GO and nafion and successfully used for sensing of GSH in the presence of H2O2 as catalyst with Michaelis-Menten constant about 0.131 mmol/L. The active surface are of GCE improve from 0.183 cm2 to 0.225 cm2 after modification with GO. The introduced biosensor (GSH-Px/GO/nafion/GCE) was used for monitoring of GSH over the range 0.003-370.0 µM, with a detection limit of 1.5 nM using differential pulse voltammetric (DPV) method. The GSH-Px/GO/nafion/GCE was successfully applied to the determination of GSH in real samples.

Rheological characteristics of wheat-chickpea composite flour doughs and effect of Amla powder (Phyllanthus emblica L.) addition on the functional properties of bread.

Bread is a staple food for majority of the people worldwide, but it has a high glycemic effect. Substituting wheat flour partly with chickpea flour and the presence of bran is suggested to improve the glycemic effect of bread; however, the non-gluten substances in wheat flour adversely affect dough rheology. The addition of amla powder was tested on the rheological properties of wheat-chickpea flour composite doughs; also, the physical and sensory qualities of bread made thereof. The results showed that when the level of replacement of refined white flour (WF) or whole wheat flour (WWF) with chickpea flour was increased from 0 to 40%, it significantly affected the rheological properties and functionality of dough. A decreased farinograph water absorption, higher mixing tolerance index (i.e., weakening of dough), decreased resistance to extension, and lower ratio numbers were obtained with some differences between WF and WWF at the higher level of chickpea flour substitution. The addition of amla powder to WF: chickpea flour (60:40) blends reduced the angle of ascending (from 7.0 ± 0.7 to 6.0 ± 0.7) and angel of descending (from 3.2 ± 0.21 to 2.4 ± 0.2), indicating the slight tightening of gluten leading to dough breakdown. The addition of amla powder improved the mixing characteristics of the composite flour doughs, as well as the physical and sensory qualities of the bread. In conclusion, amla powder can help overcome the deleterious impact of adding chickpea flour to WF or WWF for producing good quality pan bread for people with type-2 diabetes.

Fabrication of titanium dioxide nanomaterial for implantable highly flexible composite bioelectrode for biosensing applications.

Implantable and stretchable electrodes have managed to progress the medical field from a medical diagnosis aspect to a patient treatment level. They offer the ability to detect biosignals and conduct electrical current to tissues that aid in muscle stimulation and axon regeneration. Current conventional electrodes are fabricated from stiff and very expensive, precious metals such as platinum. In this work, novel, low cost, and highly flexible electrode materials were fabricated based on titanium dioxide (TiO2) and polymethyl methacrylate (PMMA) supported by a silicone polymer matrix. The electrode materials were characterized by their electrochemical, mechanical, and surface properties. The electrodes possessed high flexibility with Young's modulus of 235 kPa, revealing highly stretchable characteristics. The impedance at 1 kHz was around 114.6 kΩ, and the charge capacity was 1.23 mC/cm2. The fabricated electrodes appeared to have a smooth surface, as seen in the scanning electron microscope micrographs, compared with electrodes in the literature. Long-time stability tests revealed an overall decrease in impedance and an increase in the charge capacity up to 475% of the initial value within three weeks.

Environmental impacts of solar photovoltaic systems: A critical review of recent progress and future outlook.

Photovoltaic (PV) systems are regarded as clean and sustainable sources of energy. Although the operation of PV systems exhibits minimal pollution during their lifetime, the probable environmental impacts of such systems from manufacturing until disposal cannot be ignored. The production of hazardous contaminates, water resources pollution, and emissions of air pollutants during the manufacturing process as well as the impact of PV installations on land use are important environmental factors to consider. The present study aims at developing a comprehensive analysis of all possible environmental challenges as well as presenting novel design proposals to mitigate and solve the aforementioned environmental problems. The emissions of greenhouse gas (GHG) from various PV systems were also explored and compared with fossil fuel energy resources. The results revealed that the negative environmental impacts of PV systems could be substantially mitigated using optimized design, development of novel materials, minimize the use of hazardous materials, recycling whenever possible, and careful site selection. Such mitigation actions will reduce the emissions of GHG to the environment, decrease the accumulation of solid wastes, and preserve valuable water resources. The carbon footprint emission from PV systems was found to be in the range of 14-73 g CO2-eq/kWh, which is 10 to 53 orders of magnitude lower than emission reported from the burning of oil (742 g CO2-eq/kWh from oil). It was concluded that the carbon footprint of the PV system could be decreased further by one order of magnitude using novel manufacturing materials. Recycling solar cell materials can also contribute up to a 42% reduction in GHG emissions. The present study offers a valuable management strategy that can be used to improve the sustainability of PV manufacturing processes, improve its economic value, and mitigate its negative impacts on the environment.

Pilot scale production of functional foods using red palm olein: Antioxidant, vitamins' stability and sensory quality during storage.

The objective of this research work was to produce acceptable quality functional foods, namely, extruded snacks, digestive biscuits and pan bread, on a pilot scale, using vitamin E and ß-carotene-rich red palm olein (RPOL) and red palm shortening (RPS). These products were evaluated for their chemical composition and sensory quality along with the antioxidants and vitamin contents during the six months of storage at room temperature (22 ±â€¯1 °C). Extruded snacks and digestive biscuits prepared with RPOL and RPS were found to be good sources of these antioxidant vitamins. The average ß-carotene content of the control and test snacks at the end of six months of storage ranged from 26.8 to 56.1 mg/kg fat, and from 430.9 to 468.9 mg/kg fat, respectively. The total vitamin E content in control and test snacks made in Plant No. 1 decreased after six months of storage from 786.1 to 704.4 mg/kg fat, and from 765.1 to 695.4 mg/kg fat, respectively. As expected, the total tocotrienol content was four to five times higher than the total tocopherols in control biscuits. The RPOL containing 600-750 ppm of carotenes (mainly α- and ß-carotenes), 710-774 ppm of vitamin E, was found to be suitable for industrial application in producing acceptable quality pan bread, digestive biscuits and snacks. These functional foods contained significant amounts of ß-carotene and total vitamin E, indicating the possibility of producing such foods rich in these two of the important antioxidant vitamins coming from a natural source. The research findings strongly indicate that good-quality pan bread, extruded snacks and digestive biscuits can successfully be produced to offer healthier eating choices to the consumers of this region, thereby promoting better health and productivity among the population.

Emerging contaminants in the water bodies of the Middle East and North Africa (MENA): A critical review.

Many emerging contaminants (ECs) are not currently removed by conventional water treatment methods and consequently, often reach the aquatic environment. In the absence of proper management strategies, ECs can accumulate in water bodies, which poses potential environmental and health risks. This paper critically reviews, for the first time, the reported occurrence and treatment of ECs in the Middle Eastern and North Africa (MENA) region. The paper also provides recommendations to properly manage EC risks. In the MENA region, pharmaceuticals and personal care products (PPCPs) have been detected in surface water, seawater, groundwater, and wastewater treatment plants. A focus on surface water in the published literature suggests that studies are skewed towards worldwide trends, whereas studies on ECs in seawater are of great importance in the study region. The types of PPCPs detected in the MENA region vary, but anti-inflammatories and antibiotics dominate. In comparison, microplastics have mainly been studied in surface waters and seawater with much less focus on drinking water. The majority of microplastics in the region are secondary types resulting from the degradation of larger plastic debris; polyethylene (PE) and polypropylene (PP) fibers are the most frequently detected polymers, which are indicative of local anthropogenic sources. Research progress on ECs varies between countries, having received more attention in Iran and Tunisia. Most MENA countries have now begun monitoring water bodies for ECs; however, studies are still lacking in some countries including Sudan, Djibouti, Syria, Ethiopia, and Bahrain. Based on this review, critical knowledge gaps and research needs are identified. Countries in the MENA region require further research on a broader range of EC types. Overall, water pollution due to the use and release of ECs can be tackled by improving public awareness, public campaigns, government intervention, and advanced monitoring and treatment methods.