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Oil spills causes severe degradation to marine ecosystems and poses long term health effects on many animals on the food chain, including humans. A potential viable eco-friendly solution to oil spill clean-ups is the utilization of wool waste fibers as sorbent material, due to is naturally oleophilic nature and abundance as a waste. Repurposing wool waste also allow us to tackle another issue this waste poses: decreasing landfill spaces. This study aims to develop wool aerogels using wool waste fibers and polyvinyl alcohol (PVA) as a cross-linking binder. The synthesized aerogels exhibit high porosity (97.73–99.63%) and low densities (0.004–0.023 g/cm3). After being coated with methyltriethoxysilane (MTEOS), the aerogels exhibit great hydrophobicity with contact angles up to 138°. Using pseudo-first and pseudo-second order models to study the kinetics of the aerogels’ oil absorption performance, it is found that the oil absorption kinetics is better modelled after the pseudo-second order model. The best performing wool-based aerogel recorded an oil absorption capacity of 136.2 g/g, an estimated 9.1 and 15.3 times better than commercial counterparts, polypropylene mat and nonwoven polypropylene respectively. The aerogel fabrication technique (freeze–drying) employed in this study is also 2.5 times faster than the conventional solgel method. The promising results obtained demonstrate that the wool fiber as a great material capable of generating high engineering value and provides a novel alternative in solving environmental impacts plagued by oil spills and landfill-demanding wool waste. more...

PURPOSE: Skin and soft tissue infections are increasingly prevalent and often complicated by potentially fatal therapeutic hurdles, such as poor drug perfusion and antibiotic resistance. Delivery vehicles capable of versatile loading may improve local bioavailability and minimize systemic toxicities yet such vehicles are not clinically available. Therefore, we aimed to expand upon the use of glutathione-conjugated poly(ethylene glycol) GSH-PEG hydrogels beyond protein delivery and evaluate the ability to deliver traditional therapeutic molecules. METHODS: PEG and GSH-PEG hydrogels were prepared using ultraviolet light (UV)-polymerization. Hydrogel loading and release of selected drug candidates was examined using UV-visible spectrometry. Therapeutic molecules and GST-fusion protein loading was examined using UV-visible and fluorescent spectrometry. Efficacy of released meropenem was assessed against meropenem-sensitive and -resistant P. aeruginosa in an agar diffusion bioassay. RESULTS: For all tested agents, GSH-PEG hydrogels demonstrated time-dependent loading whereas PEG hydrogels did not. GSH-PEG hydrogels released meropenem over 24 hours. Co-loading of biologic and traditional therapeutics into a single vehicle was successfully demonstrated. Meropenem-loaded GSH-PEG hydrogels inhibited the growth of meropenem-sensitive and resistant P. aeruginosa isolates. CONCLUSION: GSH ligands within GSH-PEG hydrogels allow loading and effective delivery of charged therapeutic agents, in addition to biologic therapeutics. more...

A novel and efficient protocol for oxidation of cumene to cumene hydroperoxide was presented using ambient O2 catalyzed by very simple metalloporphyrins. The selectivity toward cumene hydroperoxide reached 98.3% in the cumene conversion of 28.1% with T(4-COOH)PPCu as a catalyst at 80[Formula: see text]C. The origin of the higher performance of T(4-COOH)PPCu was mainly ascribed to the low catalytic performance of copper(II) in the cumene hydroperoxide decomposition, and the ability of T(4-COOH)PP in stabilizing cumene hydroperoxide through hydrogen-bond interactions between them. Compared with current industrial processes and academic research in oxidation of cumene to cumene hydroperoxide with O2, the main superiorities of this protocol were the high selectivity, high conversion, simple catalysts, solvent-free, additive-free and mild conditions which made this work an appealing reference for the industrial oxidation of cumene to cumene hydroperoxide, as well as the oxidative functionalization of other C-H bonds in various hydrocarbons. more...

Over 60 million tons of aluminium are produced annually, requiring sustainable and eco-friendly recycling methods of aluminium waste. In this work, aluminium metal waste is utilized in the fabrication of aluminium hydroxide aerogels using a cost-effective and environmental-friendly process. The developed aerogels with varying contents of aluminium and poly(vinyl alcohol) as a binder exhibit a low density (0.060–0.108 g/cm3), a high porosity (92.3–95.5%) and a low electrical conductivity ([1.8–5.2] × 10–8 S/m). The results indicated that aluminium hydroxide aerogels have an ultra-low thermal conductivity of 0.028–0.032 W/m K and are able to withstand high temperature of 800 °C with less than 50% decomposition. It is suggested that the synthesized aerogels can be a promising candidate for high-value engineering applications such as thermal insulation of pipes and buildings to expand the usage of recycled aluminium. more...

Carbon nanotube (CNT) fibers are currently seen as very promising candidates for many applications within the area of smart textiles and e-textiles. However, up to now many of the practical aspects of their implementation in textiles have received little attention, these including the everyday treatments of textiles (i.e., washing) as well as the industrial processes of coloring or texturing. The following paper shows that these integration issues may be overcome by coating the nanotube fibers with a thin uniform sheath of textile polymer. Such a coating will enable repeated washing, dyeing and texturing of the fibers, whilst simultaneously providing very effective electrical insulation and separation from the human body. From the user’s perspective, the hybrid fibers will appear similar to traditional textile threads, while maintaining the original light weight, electrical conductivity and mechanical strength of the bare nanotube fibers. The work presents methods that can be utilized in the preparation of hybrid CNT fibers. These methods have been tested on both dry- and wet-spun nanotube fibers. The work includes extensive mechanical, electrical and laundry tests as well as the scanning electron microscopy characterization of bare, straight hybrid and textured fibers. Finally, examples of applications for coated fibers are presented. more...

For the first time, hydrophobic polymer-based aerogels have been developed from polypropylene fibers for heat insulation and oil spill treatments. By physically cross-linking polypropylene fibers with non-toxic polyvinyl alcohol and carboxymethyl cellulose, followed by eco-friendly freeze–drying method, the fabricated aerogels exhibit an extremely low density of 0.024–0.054 g/cm3 and a high porosity of 94.71–97.82%. The developed polypropylene aerogels express excellent flexibility and good heat insulation with remarkably low compressive modulus and thermal conductivity of 27.54–58.58 kPa and 0.036–0.039 W/m.K, respectively. Experimental results have demonstrated that methyltrimethoxysilane-coated PP aerogels have great water repellency with a water contact angle of 123.5–133.8°. Therefore, they show a good maximum absorption capacity of 12.9–27.3 g/g for fuel oil, 10.2–24.5 g/g for 5w30 motor oil, and 10.2–23.5 g/g for diesel oil; these good characteristics are attributed to their porous hollow structure. Moreover, the oil absorption of polypropylene aerogels in this work is 5 times better than that of the previous one and equivalent to that of commercial absorbents and other polymer aerogels from plastics. more...

Pineapple leaf and cotton waste fibers known as abundant by-products in the agriculture and textile industry are combined for the first time to produce thermal insulating and flexible cellulose-based aerogel composites via an environmentally friendly and cost-effective freeze-drying process. The effect of total fiber content and the ratio of pineapple leaf fibers (PF) to cotton waste fibers (CF) on the density, porosity, morphology, durability, and thermal properties of aerogel composites are comprehensively investigated. The as-fabricated aerogel composites show an exceedingly low density of 0.019–0.046 g cm−3 with high porosity of more than 96%. Because of the porous structure inside, our aerogel composites exhibit outstanding heat insulation with extraordinarily low thermal conductivity of 0.039–0.043 W m−1 K−1 that is comparable to commercial insulation materials (mineral wool, fiberglass, polystyrene) and previous cellulose-based aerogels from recycled cellulose fibers, sugarcane bagasse, and rice straw. Interestingly, the combination of those fibers has remarkably improved the flexibility of our previous aerogels from pineapple leaf fibers only, in particular, the compressive modulus of aerogel composites (11.33–44.63 kPa) is 6 times higher than that of PF aerogels (5.73 kPa). The sheet of aerogel composite with a dimension of 28 × 28 cm which is rolled up shows no crack on its surface, demonstrating its excellent mechanical strength. The research results increase the possibility of applying the developed aerogel composites from biomass into practical insulation. more...

The catalytic oxidation of cycloalkanes using molecular oxygen employing porphyrin cobalt(II) as catalyst was enhanced through use of cycloalkyl hydroperoxides, which are the primary intermediates in oxidation of cycloalkanes, as additional oxidants to further oxidize cycloalkanes in the presence of porphyrin copper(II), especially for cyclohexane, for which the selectivity was enhanced from 88.6 to 97.2% to the KA oil; at the same time, the conversion of cyclohexane was enhanced from 3.88 to 4.41%. The enhanced efficiency and selectivity were mainly attributed to the avoided autoxidation of cycloalkanes and efficient utilization of oxidation intermediate cycloalkyl hydroperoxides as additional oxidants instead of conventional thermal decomposition. In addition to cyclohexane, the protocol presented in this research is also very applicable in the oxidation of other cycloalkanes such as cyclooctane, cycloheptane and cyclopentane, and can serve as a applicable and efficient strategy to boost the conversion and selectivity simultaneously in oxidation of alkanes. This work also is a very important reference for the extensive application of metalloporphyrins in catalysis chemistry. more...

Millions of tons of plastic are produced annually, but less than 10% are reported to be recycled. This work sets out to transform environmental plastic (polyethylene terephthalate – PET) waste into aerogels for high-value engineering applications, primarily to enhance the monetary incentive in recycling plastics. Coating techniques, using silicone ceramic (SCC) and (3-aminopropyl)triethoxysilane (APS, or APTES) solutions, are successfully devised to enhance the thermal stability and CO2 adsorption capability of rPET aerogel. The rPET/SCC aerogel exhibits improved thermal stability (up to 600 °C), enhanced thermal insulation (thermal conductivity Kavg = [31.8–34.9] mW/m·K), hydrophobic characteristics (up to 144.7° in contact angle) and enhanced rigidity (Young modulus Eavg = [4.5–124.8] kPa), while maintaining an ultra-low density (ρa = [14–62] g/cm3) and a high porosity (Φavg = [95.6–99.0]%). Moreover, the amine-functionalised rPET aerogel achieves a CO2 adsorption capacity of up to 0.44 mmol CO2/g, superior to several commercial physio-sorbents. These promising results obtained demonstrate that the rPET aerogel is a versatile material suitable for a wide variety of high-value engineering applications, including thermal insulation and direct CO2 capture applications. more...

Kv1.3 potassium channels, expressed by proinflammatory central nervous system mononuclear phagocytes (CNS-MPs), are promising therapeutic targets for modulating neuroinflammation in Alzheimer’s disease (AD). The molecular characteristics of Kv1.3-high CNS-MPs and their cellular origin from microglia or CNS-infiltrating monocytes are unclear. While Kv1.3 blockade reduces amyloid beta (Aβ) burden in mouse models, the downstream immune effects on molecular profiles of CNS-MPs remain unknown. We show that functional Kv1.3 channels are selectively expressed by a subset of CD11b(+)CD45(+) CNS-MPs acutely isolated from an Aβ mouse model (5xFAD) as well as fresh postmortem human AD brain. Transcriptomic profiling of purified CD11b(+)Kv1.3(+) CNS-MPs, CD11b(+)CD45(int) Kv1.3(neg) microglia, and peripheral monocytes from 5xFAD mice revealed that Kv1.3-high CNS-MPs highly express canonical microglial markers (Tmem119, P2ry12) and are distinct from peripheral Ly6c(high)/Ly6c(low) monocytes. Unlike homeostatic microglia, Kv1.3-high CNS-MPs express relatively lower levels of homeostatic genes, higher levels of CD11c, and increased levels of glutamatergic transcripts, potentially representing phagocytic uptake of neuronal elements. Using irradiation bone marrow CD45.1/CD45.2 chimerism in 5xFAD mice, we show that Kv1.3(+) CNS-MPs originate from microglia and not blood-derived monocytes. We show that Kv1.3 channels regulate membrane potential and early signaling events in microglia. Finally, in vivo blockade of Kv1.3 channels in 5xFAD mice by ShK-223 reduced Aβ burden, increased CD11c(+) CNS-MPs, and expression of phagocytic genes while suppressing proinflammatory genes (IL1b). Our results confirm the microglial origin and identify unique molecular features of Kv1.3-expressing CNS-MPs. In addition, we provide evidence for CNS immunomodulation by Kv1.3 blockers in AD mouse models resulting in a prophagocytic phenotype. more...

In the last 5 years inhibitors of the potassium channel KV1.3 have been shown to reduce neuroinflammation in rodent models of ischemic stroke, Alzheimer’s disease, Parkinson’s disease and traumatic brain injury. At the systemic level these beneficial actions are mediated by a reduction in microglia activation and a suppression of pro-inflammatory cytokine and nitric oxide production. However, the molecular mechanisms for the suppressive action of KV1.3 blockers on pro-inflammatory microglia functions was not known until our group recently demonstrated that KV1.3 channels not only regulate membrane potential, as would be expected of a voltage-gated potassium channel, but also play a crucial role in enabling microglia to resist depolarizations produced by the danger signal ATP thus regulating calcium influx through P2X4 receptors. We here review the role of KV1.3 in microglial signaling and show that, similarly to their role in T cells, KV1.3 channels also regulated store-operated calcium influx in microglia. more...

Microglia‐mediated inflammation exerts adverse effects in ischemic stroke and in neurodegenerative disorders such as Alzheimer's disease (AD). Expression of the voltage‐gated potassium channel Kv1.3 is required for microglia activation. Both genetic deletion and pharmacological inhibition of Kv1.3 are effective in reducing microglia activation and the associated inflammatory responses, as well as in improving neurological outcomes in animal models of AD and ischemic stroke. Here we sought to elucidate the molecular mechanisms underlying the therapeutic effects of Kv1.3 inhibition, which remain incompletely understood. Using a combination of whole‐cell voltage‐clamp electrophysiology and quantitative PCR (qPCR), we first characterized a stimulus‐dependent differential expression pattern for Kv1.3 and P2X4, a major ATP‐gated cationic channel, both in vitro and in vivo. We then demonstrated by whole‐cell current‐clamp experiments that Kv1.3 channels contribute not only to setting the resting membrane potential but also play an important role in counteracting excessive membrane potential changes evoked by depolarizing current injections. Similarly, the presence of Kv1.3 channels renders microglia more resistant to depolarization produced by ATP‐mediated P2X4 receptor activation. Inhibiting Kv1.3 channels with ShK‐223 completely nullified the ability of Kv1.3 to normalize membrane potential changes, resulting in excessive depolarization and reduced calcium transients through P2X4 receptors. Our report thus links Kv1.3 function to P2X4 receptor‐mediated signaling as one of the underlying mechanisms by which Kv1.3 blockade reduces microglia‐mediated inflammation. While we could confirm previously reported differences between males and females in microglial P2X4 expression, microglial Kv1.3 expression exhibited no gender differences in vitro or in vivo. Main Points The voltage‐gated K+ channel Kv1.3 regulates microglial membrane potential.Inhibition of Kv1.3 depolarizes microglia and reduces calcium entry mediated by P2X4 receptors by dissipating the electrochemical driving force for calcium., Main Points The voltage‐gated K+ channel Kv1.3 regulates microglial membrane potential.Inhibition of Kv1.3 depolarizes microglia and reduces calcium entry mediated by P2X4 receptors by dissipating the electrochemical driving force for calcium. more...

[Image: see text] We describe a cysteine-rich, membrane-penetrating, joint-targeting, and remarkably stable peptide, EgK5, that modulates voltage-gated K(V)1.3 potassium channels in T lymphocytes by a distinctive mechanism. EgK5 enters plasma membranes and binds to K(V)1.3, causing current run-down by a phosphatidylinositol 4,5-bisphosphate-dependent mechanism. EgK5 exhibits selectivity for K(V)1.3 over other channels, receptors, transporters, and enzymes. EgK5 suppresses antigen-triggered proliferation of effector memory T cells, a subset enriched among pathogenic autoreactive T cells in autoimmune disease. PET-CT imaging with (18)F-labeled EgK5 shows accumulation of the peptide in large and small joints of rodents. In keeping with its arthrotropism, EgK5 treats disease in a rat model of rheumatoid arthritis. It was also effective in treating disease in a rat model of atopic dermatitis. No signs of toxicity are observed at 10–100 times the in vivo dose. EgK5 shows promise for clinical development as a therapeutic for autoimmune diseases. more...

Recycled polyethylene tetraphalate (rPET) fiber–silica aerogels are successfully developed from rPET fibers obtained from PET plastic bottle waste and tetraethoxysilane (TEOS). The rPET – silica aerogels are prepared through a direct gelation of silica on PET. rPET fibers are treated with dichloromethane to partially dissolve the fibers. The fibers are then dipped and allow to swell in TEOS/ethanol mixture, with the pH controlled to 2.5 using HCl to promote hydrolysis. After the acid hydrolysis, the pH was controlled to 7 with an ammonium hydroxide solution (NH4OH) to promote condensation. The surface modification is carried out in a trimethylchlorosilane (TMCS)/n-hexane solution and washed with n-hexane to dry at room temperature to prevent shrinkage. The developed rPET – silica aerogels exhibit super-hydrophobicity with an average water contact angle of 149.9°. Their thermal conductivity is approximately 0.037 W/m K. They have a very low compressive Young’s Modulus (0.95–4.19 kPa) and hence very soft. By utilizing rPET fibers, this work provides an alternative method of recycling PET plastic wastes which ultimately helps in reducing its detrimental impact to the environment. The developed aerogels can be used in several industrial applications such as heat insulation, filtering, sound insulation and absorption. more...

Recycling agricultural and aquacultural by-products into high-value engineering aerogels is a sustainable solution to minimize the negative impacts of these wastes on the environment in case of improper treatment. For the first time, discarded pineapple leaves are processed by a novel two-step procedure involving strong alkali and alkali/hydrogen peroxide treatments to generate cellulose-rich pulp containing 91.66 wt% cellulose. The mediated oxidation catalyzed by 2,2,6,6-tetramethylpiperidinyloxy is performed to introduce more carboxylate groups in the pulp for further physically interacting with amino groups on shrimp-based chitosan to synthesize unique composite aerogels without consuming any crosslinkers. The composite aerogels are ultra-lightweight and exhibit a significant rise in their compressive modulus from 2.46 to 27.25 kPa due to the chitosan addition. At the same initial dye concentration of 300 mg/L, the composite aerogels composed of 0.6 wt% chitosan achieve the equilibrium methyl orange adsorption capacity of 136.64 mg/g in only 6 min, while the highest equilibrium methylene blue adsorption uptake of 31.56 mg/g is witnessed in the samples having the lowest chitosan content (0.2 wt%). The developed composite aerogels display the notable porous structure, remarkable mechanical properties, and high removal efficiency for the two typical dyes, demonstrating the effectiveness of combining the world’s two largest natural sources by a simple and green fabrication. The approach in this study is directed towards multiple goals such as addressing the accumulation and underutilization of solid waste, dealing with water pollution caused by harmful dyes in many developing countries, and providing another solution for the cleaner production of renewable materials. more...

Haemostatic devices can exert internal pressure to promote blood clotting and reduce blood flow, potentially reducing mortality rates of gunshot wounds or other deeply penetrating wounds. For the first time, cotton aerogels have been successfully developed from commercial cotton fibers. The developed cotton aerogels can be compressed to form aerogel pallets which can be used for haemostatic devices. The effects of various cotton fiber concentrations, their morphology and chitosan concentrations on volume expansion ratio, expansion time and hydrostatic pressure of the hybrid cotton aerogels are investigated comprehensively. The chitosan-coated cellulose-cotton aerogel pallets having 0.7 wt% of the fibers, with cellulose-cotton ratio of 1:2 and 0.5 wt% of the coated chitosan showed excellent haemostatic performance. The volume expansion ratio of 16.0, expansion time of 4.5 s and hydrostatic pressure of 11.5 mmHg of each aerogel pallet are much better than those of commercial haemostatic sponges. The developed cotton-based aerogels have several potential applications such as haemostatic devices, stopping serious liquid leakage, oil-spill cleaning, personal care and heat and sound insulation applications. more...

Fly ash is waste from thermal power plants that not only has a serious impact on soil and water but also accumulates in landfills and must be treated properly. In addition, plastic waste, especially polyethylene terephthalate bottles, deteriorates for a long time, so there is an urgent need to recycle them into valuable products. To solve the environmental pollution mentioned above, a feasible zero-waste method has been developed that converts 100% of fly ash into a lightweight composite aerogel reinforced with recycled polyethylene terephthalate fiber. In this study, raw fly ash is bound to the skeleton of the fibers by a non-toxic, biodegradable xanthan gum solution as a binder, which is then lyophilized, leaving a hollow porous structure. The obtained composite aerogels display extremely low density of 0.026–0.062 g/cm3, high porosity of 96.59–98.42%, low thermal conductivity of 34–39 mW/(m·K), flexibility with Young's modulus of 3.98–20.61 kPa, and noise reduction coefficient of 0.18–0.31. Adding fly ash to the fiber framework results in a lightweight composite aerogel with higher porosity, heat, and acoustic insulation, as well as impressive compressive modulus, compared to the fly ash-free aerogels. This study provides a safe, environmentally friendly, and cost-effective solution for recycling fly ash into high-value engineering materials. more...

For the first time, successful fabrication of the cotton aerogels and cotton-cellulose aerogels is achieved using recycled fibers from environmental waste for oil absorption. The pure cotton and cotton-cellulose aerogels are obtained using a cost-effective mixing-blending method with polyamide-epichlorohydrin as strengthening additives. The obtained aerogels are silanized using methyltrimethoxysilane via a facile chemical vapor deposition to endow aerogels with hydrophobic surface. Effects of fiber concentrations and cotton-to-cellulose mass ratio on oil absorption performance in various solvents are also investigated. The cotton aerogel with an initial concentration of 0.25wt% presents the highest oil absorption capacity over 100gg−1. Besides, the cotton/cellulose aerogels also demonstrate good absorption capacity in different pollutant organics. The absorption kinetics of the aerogels with different cotton concentrations are also investigated using pseudo first-order model. Both equilibrium absorption and absorption kinetics demonstrate cotton/cellulose aerogels as promising materials for oil absorption and environmental pollution treatment. Keywords: Cotton fibers, Cellulose fibers, Aerogel, Oil absorption, Environmental waste more...

Carbon-based aerogel is a lightweight porous material with many advanced properties related to its microstructure, such as ultrahigh porosity, large surface area, and low thermal conductivity. With the extreme properties, aerogels are a potential material that can be applied to many applications as insulation and absorption. In this chapter, we briefly review the fabrication and thermal properties of carbon-based aerogels including graphene aerogels, carbon nanotube aerogels, and other aerogels. Several developed methods for fabricating and thermal properties of aerogels have been reported. The chapter is mostly based on our original and review papers dedicated to various aspects of synthesis and applications of aerogels. more...

Exercising in a tropical climate with constant high temperatures and high humidity increases the risk of heatstroke for active people who frequently train outdoors. For these active persons, a cooling source of water nearby can be essential, and this is usually carried in canteen bottles. However, commercially available water canteen bottles have limited thermal insulation capability to keep the liquid content cooled for the required period. This work proposed an engineering solution to enhance the heat insulation performance of water canteen bottles, using recycled cellulose aerogels made from paper waste for the first time as an insulating layer. Recycled cellulose aerogels wrapped around the water canteen bottle provides excellent thermal insulation performance, while not adding significant weight to the bottle. The temperature of the ice slurry in the canteen bottle was measured periodically over four hours with a mercury thermometer. The effects of the static and dynamic conditions on the temperature rate were also quantified. A 1.5 cm thickness of 1.0 wt.% recycled cellulose aerogel wrapped around the canteen bottle can provide an excellent thermal insulation performance with the lowest rise in temperature, achieving a low final temperature of the ice slurry content of 3.5 &deg, C after 4 h. This result is much better than that provided by available commercial bottles under the same conditions. more...

A promising and economic material for various applications, such as thermal insulation in construction building and oil clean-up in marine ecosystems, is successfully developed from the by-product of the sugarcane industry. Biodegradable sugarcane bagasse aerogels are produced using polyvinyl alcohol (PVA) binder, followed by a freeze-drying method. This environmental-friendly recycled aerogel has an ultra-low density ([0.016-0.112] g/cm3), a high porosity ([91.9–98.9]%), and a very low thermal conductivity ([0.031-0.042] W/mK). Its superhydrophobicity properties and its maximum oil absorption capacity (up to 25 g/g) are measured after coating aerogel samples with methyltrimethoxysilane (MTMS). The biodegradable aerogel has a Young's modulus of 88 K Pa and can be bent without breaking, demonstrating its high flexibility. more...

Utilizing the superior properties of individual carbon nanotubes (CNTs), the production of continuous CNT fibers has paved the way for novel CNT macroscale applications. However, it is still a great challenge to create highly electrically-conductive CNT fibers due to the poor transfer of electrical property from nanoscale individual CNTs to macroscale CNT fibers. Here, we report a fast and effective post treatment method consisting of mechanical condensation and acid treatment to enhance the electrical conductivity of the CNT fiber by a factor of 9. Such great enhancement is attributed to the surface modification effects during the post treatments, resulting in the lower contact resistance and stronger inter-CNT interactions. Moreover, the maximum current density of the acid-treated CNT fiber is up to 66000 A/cm2, competitive to the conventional copper wires. The promising results in this study enable the CNT fibers novel materials for electrical wiring applications. more...

Microglia are highly plastic cells that can assume different phenotypes in response to microenvironmental signals. Lipopolysaccharide (LPS) and interferon-γ (IFN-γ) promote differentiation into classically activated M1-like microglia, which produce high levels of pro-inflammatory cytokines and nitric oxide and are thought to contribute to neurological damage in ischemic stroke and Alzheimer's disease. IL-4 in contrast induces a phenotype associated with anti-inflammatory effects and tissue repair. We here investigated whether these microglia subsets vary in their K+ channel expression by differentiating neonatal mouse microglia into M(LPS) and M(IL-4) microglia and studying their K+ channel expression by whole-cell patch-clamp, quantitative PCR and immunohistochemistry. We identified three major types of K+ channels based on their biophysical and pharmacological fingerprints: a use-dependent, outwardly rectifying current sensitive to the KV 1.3 blockers PAP-1 and ShK-186, an inwardly rectifying Ba2+ -sensitive Kir 2.1 current, and a Ca2+ -activated, TRAM-34-sensitive KCa 3.1 current. Both KV 1.3 and KCa 3.1 blockers inhibited pro-inflammatory cytokine production and iNOS and COX2 expression demonstrating that KV 1.3 and KCa 3.1 play important roles in microglia activation. Following differentiation with LPS or a combination of LPS and IFN-γ microglia exhibited high KV 1.3 current densities (∼50 pA/pF at 40 mV) and virtually no KCa 3.1 and Kir currents, while microglia differentiated with IL-4 exhibited large Kir 2.1 currents (∼ 10 pA/pF at -120 mV). KCa 3.1 currents were generally low but moderately increased following stimulation with IFN-γ or ATP (∼10 pS/pF). This differential K+ channel expression pattern suggests that KV 1.3 and KCa 3.1 inhibitors could be used to inhibit detrimental neuroinflammatory microglia functions. GLIA 2016;65:106-121. more...

Silica⿿cellulose aerogels were successfully developed from recycled cellulose fibres and methoxytrimethylsilane (MTMS) silica precursor for the first time. The developed silica⿿cellulose aerogels showed the super-hydrophobicity with an average water contact angle of 151°. Their thermal conductivity was approximately 0.04 W/mK. Moreover, the thermal degradation temperature for the cellulose component of the silica⿿cellulose aerogels showed a 25 °C improvement over those for cellulose aerogels. The sound absorption coefficients of the silica⿿cellulose aerogels with a 10 mm thickness were 0.39⿿0.50, better than those of cellulose aerogels (0.30⿿0.40) and commercial polystyrene foams. When the cellulose fibre concentration increases from 1.0 to 4.0 wt.%, the compressive Young⿿s modulus of the silica⿿cellulose aerogels can be enhanced 160%, up to 139 KPa. This work provides a facile approach to fabricate cost-effective and promising silica⿿cellulose aerogels with industrial dimensions for thermal and acoustic insulation applications. more...

In this work, we report on the effective implementation of the direct and scalable floating catalyst method to synthesize self-supporting carbon nanotube (CNT) aerogels at high deposition rates. Through the adaptable process conditions, the highly porous and ultralight CNT aerogels with densities ranging from 0.55 to 32 mg/cm3 are synthesized. The aerogels exhibit high porosity (>98%) and surface areas of up to 170 m2/g with tortuous pores easy accessible to molecules of interest. Their superior electrical conductivity (up to 106 S/m), in comparison with CNT aerogels produced through other methods, indicates high potential for energy applications. The thermal conductivity has been observed to be within the range of 0.127–0.137 W/m·K as a consequence of the ultralight structure. Polymer infiltration and subsequent curing do not disturb the three-dimensional percolating CNT network and constitute an accessible method for the production of various lightweight polymeric composites. The polydimethylsiloxane-based composites (4.5% wt) with electrical conductivity enhanced by ∼16 orders of magnitude and thermal conductivity double that of pure matrix are particularly promising for use in bio-integrated devices and flexible composites. more...

Over 27 million tons of pineapples are produced globally annually, from which approximately 76.4 million tons of pineapple leaf by-product waste are generated. Even though the fibers within the pineapple leaves exhibit excellent properties, several efforts to repurpose pineapple leaf wastes have remained lack luster, with most farmers still disposing the waste to landfills or burning them in open fields. This work sets out to transform pineapple leaf fibers extracted from agricultural pineapple leaf waste into highly porous aerogel for high-value engineering applications to enhance the monetary incentive to repurpose agricultural waste. Pineapple aerogels are developed and functionalized with activated carbon and diethylenetriamine for ethylene adsorption and nickel ions removal applications, respectively. The modified aerogels maintain a porous structure with a porosity of 91.1–96.4% and density of 32.2–92.6 mg/cm3. Activated carbon coated pineapple aerogel exhibits excellent ethylene adsorption capability, with a maximum adsorption capacity of 1.08 mmol/g at atmospheric pressure, surpassing those of commercial ethylene absorbents (0.157 mmol/g). While diethylenetriamine coated pineapple aerogel shows its good nickel ion adsorption with maximum adsorption capacity of 0.835 mmol/g, as predicted by the Langmuir-Freundlich isotherm model. The results suggests modified pineapple aerogels are promising candidates for capturing ethylene in food preservation and nickel ions removal in wastewater. more...

The development of magnesium (Mg) production has led to an ever-increasing volume of magnesium waste, with detrimental effects on the environment. Recycling magnesium waste into magnesium hydroxide (MH) aerogels has been successfully developed to partially solve the problem of magnesium waste. The effects of the Mg concentration on the properties of the MH aerogel have been investigated. The MH aerogel exhibits a porous structure with a low density of 0.081–0.150 g cm−3 and a high porosity of 91.5–94.4 %. Its thermal conductivity and stability are evaluated, showing that the MH aerogel has a good thermal insulation capability with a low thermal conductivity of 30–42 mW m-1 K-1, and it is stable up to 800 °C for about 50 % weight loss. In addition, its acoustic absorption performance is also investigated. The MH aerogel performs a good acoustic absorption capability at low frequency, and its noise reduction coefficient indicates that the MH aerogel is a potential competitor to other acoustic insulators. The results demonstrate that magnesium waste can be recycled into a high-value material for thermal and acoustic insulation applications, enhancing the use of environmental wastes. more...

Petroleum spills have been described as one of the leading aquatic disasters that has resulted in the destruction and degradation of marine ecosystems worldwide, destroying the lives of thousands of organisms within a short period. Parts of the causes of this may be linked to waste products from plastics and rubber tires. This study focuses on fibers from rubber tires, and successfully produces rubber aerogels from them using glutaraldehyde and poly(vinyl alcohol) binders, followed by a freeze-drying process. Our recycled rubber aerogels are extremely pore (92.2–98.3 %) and ultra-low density (0.020−0.091 g/cm3). After a methyltrimethoxysilane (MTMS) coating, rubber aerogels show their super-hydrophobic properties with a water contact angle up to 153°. The effects of rubber fiber and cross-linker contents on the rubber aerogel oil absorption efficiency are thoroughly investigated. Pseudo-first-order and pseudo-second-order kinetics are studied for the absorption of rubber aerogel and the result shows that the pseudo-second-order model could better predict oil absorption performance. A maximum rubber aerogel oil absorption of up to 25.0 g/g is estimated, approximately 1.7 and 2.8 times higher compared to commercial polypropylene mat and nonwoven polypropylene, respectively. Such a material can play an instrumental role towards recycling of car tires and paves the way for maximizing the recycling capacity of waste rubber tires globally. This will in turn reduce the global and environmental impact of waste pollution associated with untreated car tires. more...

As their name implies, cation channels allow the regulated flow of cations such as sodium, potassium, calcium, and magnesium across cellular and intracellular membranes. Cation channels have long been known for their fundamental roles in controlling membrane potential and excitability in neurons and muscle. In this review, we provide an update on the recent advances in our understanding of the structure–function relationship and the physiological and pathophysiological role of cation channels. The most exciting developments in the last two years, in our opinion, have been the insights that cryoelectron microscopy has provided into the inner life and the gating of not only voltage-gated channels but also mechanosensitive and calcium- or sodium-activated channels. The mechanosensitive Piezo channels especially have delighted the field not only with a fascinating new type of structure but with important roles in blood pressure regulation and lung function. more...

The search for solid electrolytes with high stability and ionic conductivity is a long sought-after goal in the development of safe and high energy density Li-ion batteries. Garnet-type lithium conductors form a most promising family of materials due to their good chemical stability. However, the low conductivity at room temperature prevents wider application of these materials. It has long been recognized that alkaline earth metals are confined exclusively to dodecahedral 8-coordinated sites within the garnet framework. In contrast to this dominant viewpoint, we show that Ca2+ cations can occupy the octahedral 6-coordinated sites, leading to an enhanced room temperature conductivity of 5.2 × 10−4 S cm−1 and reduced activation energy of 0.27 eV, together with a 0 to 9 V electrochemical stability window. This finding opens up a new opportunity for the design of ceramic electrolytes with higher conductivities, providing added impetus for further exploration of oxide electrolyte chemistry. Keywords: Solid electrolyte, Garnet, Conductivity, Alkaline earth doping, Neutron diffraction more...

A facile and cost-effective synthesis method of biocompatible cellulose aerogels using recycled cellulose fibers of paper waste and Kymene crosslinker is successfully developed for the first time. After coated with methyltrimethoxysilane (MTMS) via chemical vapor deposition, the recycled cellulose aerogels yields very stable super-hydrophobicity for over five months and excellent oil absorption capacities of up to 95 g g−1 with the 0.25 wt.% cellulose aerogel. Effects of different cellulose fiber concentrations, different ratios of the cellulose and Kymene cross-linker composition, ambient temperatures and pH values of the environment on the oil absorption behavior of the cellulose aerogels are also quantified comprehensively. The experimental results show the cellulose aerogels yield the maximum absorption capacity at 50 °C. Compared to the pseudo first-order model, the pseudo second-order model is more validated for the oil absorption kinetics study. The recycled cellulose aerogels are promising for replacing earth-unfriendly polymer-based oil sorbents due to their high oil absorption capacities. more...

This study investigated the possible influence of the Subdural Pharmacotherapy Device (SPD) on spatial memory in 3 adult, male bonnet macaques (Macaca radiata). The device was implanted in and above the subdural/subarachnoid space and cranium overlaying the right parietal/frontal cortex: a circuitry involved in spatial memory processing. A large test chamber, equipped with four baited and four non-baited food-ports at different locations, was used: reaches into empty food ports were counted as spatial memory errors. In this study of within-subject design, before SPD implantation (control) the animals made mean 373.3 ± 114.9 (mean ± SEM) errors in the first spatial memory test session. This value dropped to 47.7 ± 18.4 by the 8th session. After SPD implantation and alternating cycles of transmeningeal saline delivery and local cerebrospinal fluid (CSF) drainage in the implanted cortex the spatial memory error count, with the same port locations, was 33.0 ± 12.2 during the first spatial memory test session, further decreasing to 5.7 ± 3.5 by the 8th post-implantation session (P < 0.001 for trend). Replacing transmeningeal saline delivery with similar delivery of the GABAA receptor agonist muscimol (1.0 mM) by the SPD did not affect the animals’ spatial memory performance, which in fact included at least one completely error-free session per animal over time. The study showed that complication-free implantation and use of the SPD over the parietal and frontal cortices for months leave spatial memory processes intact in nonhuman primates. more...

Heat conduction in single-walled carbon nanotube (SWNT) aerogels is investigated by an off-lattice Monte Carlo method. Thermal boundary resistances (TBRs) between the SWNT and four permeated gases of argon, nitrogen, neon and hydrogen are reported from fitting simulation results with experimental data. It is found that the TBRs between the SWNT and the permeated gases decrease with larger gas molecular masses. Effects of volume fractions and complex morphologies of SWNTs on thermal conductivities of SWNT aerogels are also quantified. The effective thermal conductivities of SWNT aerogels increase with the larger volume fraction, the greater length and the smaller diameter of the SWNTs. more...

This book chapter presents the basic facts about cellulose materials and comprehensive information about cellulose aerogels, silica–cellulose composite aerogels. Both the fabrication methods and properties of cellulose aerogels and silica–cellulose aerogels are discussed in detail. A combination of an aerogel structure and recycled cellulose fibres from paper waste can be used to form an advanced material, called a recycled cellulose aerogel, which is cost-effective and a promising material for oil absorption. This chapter also focuses on the thermal properties, such as thermal conductivity and thermal stability, of the recycled cellulose aerogels and their silica composites for the heat insulation applications. This is the first time that the benchmark data on the thermal properties of recycled cellulose-based aerogels have been summarized. Protein-based aerogels, novel biodegradable and biocompatible materials for lightweight food engineering and life science applications, are also briefly discussed. more...

In this work, graphene aerogel (GA)–poly (methyl methacrylate) (PMMA) composites are first developed by backfilling PMMA into the pores of the GAs, providing uniform distribution of multi-layer reduced graphene oxide (m-rGO) sheets in the PMMA matrix. Electrical, mechanical and thermal properties of the as-prepared GA–PMMA composites are investigated by two-probe, microindentation and comparative infrared techniques respectively. As graphene loadings increase from 0.67 to 2.50 vol.%, the composites exhibit significant increases in electrical conductivity (0.160–0.859 S/m), microhardness (303.6–462.5 MPa) and thermal conductivity (0.35–0.70 W/m K) from that of pure PMMA as well as graphene–PMMA composites prepared by traditional dispersion methods. Thermal boundary resistance between graphene and PMMA is estimated to be 1.906 × 10−8 m2 K/W by an off-lattice Monte Carlo algorithm that takes into account the complex morphology, size distribution and dispersion of m-rGO sheets. more...

Lithium solid electrolytes have shown their potential for high-energy density batteries. The use of solid electrolytes will also be able to overcome safety issues associated with conventional carbonate-based electrolytes. However, achieving the combination of high ionic conductivity and excellent electrochemical stability in lithium solid electrolytes is still a major challenge. Herein we report a facile strategy to achieve high conduction and excellent electrochemical stability by the substitution of Cl for O based on the concept of bottleneck size and binding energy. The ionic conductivities of Li10.42Si1.5P1.5Cl0.08O11.92 and Li10.42Ge1.5P1.5Cl0.08O11.92 are 1.03 × 10−5 S cm−1 and 3.7 × 10−5 S cm−1 at 27 °C, respectively, which are 13 orders of magnitude higher than that of the pure Li3PO4, and 1 order of magnitude higher than that of the pristine Li10.5Si1.5P1.5O12. The electrochemical stability with metallic lithium is up to 9 V vs. Li+/Li, which is one of the widest electrochemical windows of solid electrolytes. This research also addresses the crystal structure, lithium ion migration mechanism, and battery performance. more...

In this work, we have successfully developed three-dimensional (3D) nickel hydroxide (Ni(OH)2)/single-walled carbon nanotube (SWNT) gel composites for supercapacitor applications. The composites are prepared using a facile coating-aging method followed by an electrochemical deposition. The obtained SWNT gels and their derived Ni(OH)2/SWNT composites present 3D network structures composed of randomly orientated nanotube bundles. It is found that the sizes of these bundles can be easily tuned using two different drying techniques. The directly dried Ni(OH)2/SWNT composites with seriously bundled nanotubes are capable of maintaining an excellent discharge performance as well as a satisfactory cycling stability. The improved electrochemical performance of the Ni(OH)2/SWNT xerogel composite comes from a 3D SWNT conductive highway and a stronger Ni(OH)2/SWNT interface bonding. In contrast, the hydrogel composite prepared in the absence of a drying process, despite achieving both high areal and mass-based capacitance, suffers a severe cycling drop. Compared with 3D graphene and its derived composites, our composite design with the employment of 1D SWNTs has the merit of shorter ion diffusion distances which offers a distinctive opportunity for the future development of 3D electrodes. more...

Thermal jacket design using eco-friendly cellulose fibers from recycled paper waste is developed in this report. Neoprene as an outmost layer, cellulose aerogels in the middle and Nylon as an innermost layer can form the best sandwiched laminate using the zigzag stitching method for thermal jacket development. The temperature of the ice slurry inside the water bottle covered with the designed thermal jackets remains at 0.1 °C even after 4 h, which is the average duration of an outfield exercise. Interestingly, the insulation performance of the designed thermal jackets is much better than the commercial insulated water bottles like FLOE bottles and is very competition to that of vacuum flasks for a same period of 4 h and ambient conditions. more...

In this study, we apply a simple but effective oxidative purification method to purify carbon nanotube (CNT) fibers synthesized via a floating catalyst technique. After the purification treatment, the resulting CNT fibers exhibited significant improvements in mechanical and electrical properties with an increase in strength, Young’s modulus, and electrical conductivity by approximately 81, 230, and 100%, respectively. With the successful dissolution of the CNT fibers in superacid, an extensional viscosity method could be applied to measure the aspect ratio of the CNTs constituting the fibers, whereas high-purity CNT thin films could be produced with a low resistance of 720 Ω/sq at a transmittance of 85%. This work suggests that the oxidative purification approach and dissolution process are promising methods to improve the purity and performance of CNT macroscopic structures. more...

There is a need for fast detection methods for the banned rodenticide tetramethylenedisulfotetramine (TETS), a highly potent blocker of the γ-aminobutyric acid (GABAA ) receptors. General synthetic approach toward two groups of analogues was developed. Screening of the resulting library of compounds by FLIPR or whole-cell voltage-clamp revealed that, despite the structural differences, some of the TETS analogues retained GABAA receptor inhibition; however, their potency was an order of magnitude lower. Antibodies raised in rabbits against some of the TETS analogues conjugated to protein recognized free TETS and will be used for the development of an immunoassay for TETS. more...

© 2017 by The American Society for Pharmacology and Experimental Therapeutics. The intermediate-conductance Ca2+-activated K+channel (KCa3.1) constitutes an attractive pharmacological target for immunosuppression, fibroproliferative disorders, atherosclerosis, and stroke. However, there currently is no available crystal structure of this medically relevant channel that could be used for structure-assisted drug design. Using the Rosetta molecular modeling suite we generated a molecular model of the KCa3.1 pore and tested the model by first confirming previously mapped binding sites and visualizing the mechanism of TRAM- 34 (1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole), senicapoc (2,2-bis-(4-fluorophenyl)-2-phenylacetamide), and NS6180 (4-[[3- (trifluoromethyl)phenyl]methyl]-2H-1,4-benzothiazin-3(4H)-one) inhibition at the atomistic level. All three compounds block ion conduction directly by fully or partially occupying the site that would normally be occupied by K+before it enters the selectivity filter. We then challenged the model to predict the receptor sites andmechanismsof action of the dihydropyridine nifedipine and an isosteric 4-phenyl-pyran. Rosetta predicted receptor sites for nifedipine in the fenestration region and for the 4-phenyl-pyran in the pore lumen, which could both be confirmed by site-directed mutagenesis and electrophysiology. While nifedipine is thus not a pore blocker and might be stabilizing the channel in a nonconducting conformation or interfere with gating, the 4-phenylpyran was found to be a classical pore blocker that directly inhibits ion conduction similar to the triarylmethanes TRAM-34 and senicapoc. The Rosetta KCa3.1 pore model explains the mechanism of action of several KCa3.1 blockers at the molecular level and could be used for structure-assisted drug design. more...

Given the harmful effects of agricultural waste residues on the environment and the abundance of pineapple byproducts after harvest, converting pineapple waste into a high-engineering value product for practical applications is one of the solutions toward sustainable development in developing countries. For the first time, flexible cellulose aerogels from raw pineapple-leave fibers (PALF) are developed successfully by using an adhesive agent, polyvinyl alcohol (PVA), and deionized (DI) water as a solvent, followed by a freeze-drying process. The effects of the pineapple fiber (PF) concentration on the heat and acoustic insulation properties are also investigated. The PF aerogels show high porosities of nearly 99%, ultra-low densities of (0.013–0.033) g/cm3, and a microporous structure which are determined by FE-SEM, BET and XRD analysis. They have very low thermal conductivities of (0.030–0.034) W/mK, indicating their excellent suitability for heat insulation applications. Indeed, the thermal jacket using a PF aerogel as filler wrapped around a water bottle can maintain the water temperature below 0 °C for 6 h (initial temperature of −3 °C), and above 40 °C for 2.5 h (initial temperature of 90 °C). The heat insulation capacity of the thermal jacket is about three times better than that of a commercially available product. With the same thickness, the noise reduction coefficient of 2.0 wt% PF aerogel samples is greater than that of a commercial absorber Basmel, which demonstrates their potential in acoustic insulation applications. more...

Recycled polyethylene terephthalate (rPET) aerogels are successfully developed using rPET fibers from plastic bottle wastes for oil spill cleaning applications. The rPET aerogels are formed via a freeze-drying process with polyvinyl alcohol (PVA) and glutaraldehyde (GA) crosslinking agents. After coating with methyltrimethoxysilane (MTMS), the MTMS-coated rPET aerogels exhibit hydrophobicity with a water contact angle of 133°–141° for oil absorption applications. The effects of the rPET fiber concentrations, fiber deniers and cross-linker contents on the oil absorption performance of the rPET aerogels are comprehensively quantified. The 0.5 wt% rPET aerogels show the largest oil absorption capacity of 79.4 g/g, approximately 7.0 and 3.2 times better than commercial sorbents, polypropylene pads and polypyrrole sponges, respectively and slightly larger than 0.5 wt% cellulose-based aerogels from paper waste. From the oil absorption kinetics of the rPET aerogels quantified by the pseudo-first and pseudo–second order models, the 0.5 wt% rPET aerogels can absorb oil up to 3.0 times faster than cellulose-based aerogels. In addition, rPET aerogels are also demonstrated to have a good absorption capacity for different organic solvents. These establish the novelty of the contribution and demonstrate that rPET aerogels can be promising materials for absorption applications due to their high absorption capacities, environmental-friendly and cost-effective fabrication method. more...

Garnet-structured Li 7 La 3 Zr 2 O 12 is stabilized through Cr 3 + doping at Zr 4 + sites. The Rietveld refinement of powder XRD data is used to analyze the crystal structure and Cr site. The migration mechanisms of lithium ions are dependent on the hopping of lithium ions at different sites. Three possible migration pathways are proposed, in which lithium ions transport via the tetrahedral sites. Small doping of Cr 3 + at Zr 4 + sites leads to high total conductivity of the 0.1 mol Cr-stabilized Li 7.1 La 3 Zr 1.9 Cr 0.1 O 12 to be 5.2 × 10 − 4 S cm − 1 at 27 °C. The sample shows a wide electrochemical stability up to 6 V. more...

An Off-Lattice Monte Carlo model was developed to investigate effective thermal conductivities ( K eff ) and thermal transport limitations of polymer composites containing carbon nanotubes (CNTs) and inorganic nanoparticles. The simulation results agree with experimental data for poly(ether ether ketone) (PEEK) with inclusions of CNTs and tungsten disulfide (WS 2 ) nanoparticles. The developed model can predict the thermal conductivities of multiphase composite systems more accurately than previous models by taking into account interfacial thermal resistance ( R bd ) between the nanofillers and the polymer matrix, and the nanofiller orientation and morphology. The effects of (i) R bd of CNT–PEEK and WS 2 –PEEK (0.0232–115.8 × 10 −8 m 2 K/W), (ii) CNT concentration (0.1–0.5 wt%), (iii) CNT morphology (aspect ratio of 50–450, and diameter of 2–8 nm), and (iv) CNT orientation (parallel, random and perpendicular to the heat flux) on K eff of a multi-phase composite are quantified. The simulation results show that K eff of multiphase composites increases when the CNT concentration increases, and when the R bd of CNT–PEEK and WS 2 –PEEK interfaces decrease. The thermal conductivity of composites with CNTs parallel to the heat flux can be enhanced ∼2.7 times relative to that of composites with randomly-dispersed CNTs. CNTs with larger aspect ratio and smaller diameter can significantly improve the thermal conductivity of a multiphase polymer composite. more...