Long-term evaluation of palm oil mill effluent (POME) steam reforming over lanthanum-based perovskite oxides.

To replace the obsolete ponding system, palm oil mill effluent (POME) steam reforming (SR) over net-acidic LaNiO3 and net-basic LaCoO3 were proposed as the POME primary treatments, with promising H2-rich syngas production. Herein, the long-term evaluation of POME SR was scrutinized with both catalysts under the optimal conditions (600 °C, 0.09 mL POME/min, 0.3 g catalyst, & 74-105 µm catalyst particle size) to examine the catalyst microstructure changes, transient process stability, and final effluent evaluation. Extensive characterization proved the (i) adsorption of POME vapour on catalysts before SR, (ii) deposition of carbon and minerals on spent SR catalysts, and (iii) dominance of coking deactivation over sintering deactivation at 600 °C. Despite its longer run, spent LaCoO3 (50.54 wt%) had similar carbon deposition with spent LaNiO3 (50.44 wt%), concurring with its excellent coke resistance. Spent LaCoO3 (6.12 wt%; large protruding crystals) suffered a harsher mineral deposition than spent LaNiO3 (3.71 wt%; thin film coating), confirming that lower reactivity increased residence time of reactants. Transient syngas evolution of both SR catalysts was relatively steady up to 4 h but perturbed by coking deactivation thereafter. La2O2CO3 acted as an intermediate species that hastened the coke removal via reverse Boudouard reaction upon its decarbonation. La2O2CO3 decarbonation occurred continuously in LaCoO3 system but intermittently in LaNiO3 system. LaNiO3 system only lasted for 13 h as its compact ash blocked the gas flow. LaCoO3 system lasted longer (17 h) with its porous ash, but it eventually failed because KCl crystallites blocked its active sites. Relatively, LaCoO3 system offered greater net H2 production (72.78%) and POME treatment volume (30.77%) than LaNiO3 system. SR could attain appreciable POME degradation (>97% COD, BOD5, TSS, & colour intensity). Withal, SR-treated POME should be polished to further reduce its incompliant COD and BOD5.

3D Printing Methyl Cellulose Hydrogel Wound Dressings with Parameter Exploration Via Computational Fluid Dynamics Simulation.

PURPOSE: To investigate and optimize the use of methyl cellulose in the fabrication of three-dimensional (3D) printed drug-loaded hydrogel wound dressings for the treatment of burns. METHOD: The effects of incorporating various salts on the properties of methyl cellulose, especially the gelation temperature was investigated for methyl cellulose to undergo gelation at skin temperature (i.e., 31.7°C). The optimized methyl cellulose and salt compositions were then loaded with various drugs beneficial for the treatment of burns. Printability and cumulative release profiles for selected drugs were then obtained, which were then fitted to common release kinetic models. Computational Fluid Dynamics (CFD) simulation was also explored to investigate the relationship between printing parameters and the hydrogel filament produced during extrusion. RESULTS: The printed hydrogels had moderate dimensional integrity, were found to be stable for up to 2 weeks and demonstrated good swelling properties. In vitro drug release studies of various drugs showed that the hydrogel was able to release various drugs within 6 h and release profiles were fitted to common in vitro drug release models, such as the Korsmeyer Peppas model and the Weibull model. While there were deviations from the actual printing process, CFD simulation was able to predict the shape of the printed structure and showed fair accuracy in determining the mass flow rate and line width of extruded hydrogels. CONCLUSIONS: Methyl cellulose hydrogels with optimized salt composition demonstrated suitable properties for a wound dressing application, revealing its potential to be used for in situ wound dressing applications.

Sustainable and Highly Efficient Recycling of Plastic Waste into Syngas via a Chemical Looping Scheme.

Converting plastic waste into valuable products (syngas) is a promising approach to achieve sustainable cities and communities. Here, we propose for the first time to convert plastic waste into syngas via the Fe2AlOx-based chemical looping technology in a two-zone reactor. The Fe2AlOx-based redox cycle was achieved with the pyrolysis of plastic waste in the upper zone, followed by the decomposition and thermal cracking of hydrocarbon vapors, and the oxidation and water splitting in the lower zone (850 °C) enabled a higher carbon conversion (81.03%) and syngas concentration (92.84%) when compared with the mixed feeding process. The iron species could provide lattice oxygen and meanwhile act as the catalyst for the deep decomposition of hydrocarbons into CO and the accumulation of deposited carbon in the reduction step. Meanwhile, the introduced water would be split by the reduced iron and deposited carbon to further produce H2 and CO in the following oxidation step. A high hydrogen yield of 85.82 mmol/g HDPE with a molar ratio of H2/CO of 2.03 was achieved from the deconstruction of plastic waste, which lasted for five cycles. This proof of concept demonstrated a sustainable and highly efficient pathway for the recycling of plastic waste into valuable chemicals.

Designer biochar with enhanced functionality for efficient removal of radioactive cesium and strontium from water.

Radioactive elements released into the environment by accidental discharge constitute serious health hazards to humans and other organisms. In this study, three gasified biochars prepared from feedstock mixtures of wood, chicken manure, and food waste, and a KOH-activated biochar (40% food waste + 60% wood biochar (WFWK)) were used to remove cesium (Cs+) and strontium (Sr2+) ions from water. The physicochemical properties of the biochars before and after adsorbing Cs+ and Sr2+ were determined using X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, extended X-Ray absorption fine structure (EXAFS) spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX). The WFWK exhibited the highest adsorption capacity for Cs+ (62.7 mg/g) and Sr2+ (43.0 mg/g) among the biochars tested herein. The removal of radioactive 137Cs and 90Sr exceeded 80% and 47%, respectively, in the presence of competing ions like Na+ and Ca2+. The functional groups present in biochar, including -OH, -NH2, and -COOH, facilitated the adsorption of Cs+ and Sr2+. The Cs K-edge EXAFS spectra revealed that a single coordination shell was assigned to the Cs-O bonding at 3.11 Å, corresponding to an outer-sphere complex formed between Cs and the biochar. The designer biochar WFWK may be used as an effective adsorbent to treat radioactive 137Cs- and 90Sr-contaminated water generated during the operation of nuclear power plants and/or unintentional release, owing to the enrichment effect of the functional groups in biochar via alkaline activation.

Plastic-containing food waste conversion to biomethane, syngas, and biochar via anaerobic digestion and gasification: Focusing on reactor performance, microbial community analysis, and energy balance assessment.

To manage the mixture of food waste and plastic waste, a hybrid biological and thermal system was investigated for converting plastic-containing food waste (PCFW) into renewable energy, focusing on performance evaluation, microbial community analysis, and energy balance assessment. The results showed that anaerobic digestion (AD) of food waste, polyethylene (PE)-containing food waste, polystyrene (PS)-containing food waste, and polypropylene (PP)-containing food waste generated a methane yield of 520.8, 395.6, 504.2, and 479.8 mL CH4/gVS, respectively. CO2 gasification of all the plastic-containing digestate produced more syngas than pure digestate gasification. Syngas from PS-digestate reached the maximum yield of 20.78 mol/kg. During the digestate-derived-biochar-amended AD of PCFW, the methane yields in the biochars-amended digesters were 6-30% higher than those of the control digesters. Bioinformatic analysis of microbial communities confirmed the significant difference between control and biochar-amended digesters in terms of bacterial and methanogenic compositions. The enhanced methane yields in biochars-amended digesters could be partially ascribed to the selective enrichment of genus Methanosarcina, leading to an improved equilibrium between hydrogenotrophic and acetoclastic methanogenesis pathways. Moreover, energy balance assessment demonstrated that the hybrid biological and thermal conversion system can be a promising technical option for the treatment of PCFW and recovery of renewable biofuels (i.e., biogas and syngas) and bioresource (i.e., biochar) on an industrial scale.

Co-transesterification of waste cooking oil, algal oil and dimethyl carbonate over sustainable nanoparticle catalysts.

Key challenges for the application of biodiesel include their high acid value, high viscosity, and low ester content. It is essential to develop later-generation biodiesel from unexploited non-food resources for a more sustainable future. Reuse of biowaste is critically important to address these issues of food safety and sustainability. Thus, the co-transesterification of waste cooking oil (WCO), algal oil (AO) and dimethyl carbonate (DMC) for the synthesis of fatty acid methyl esters (FAMEs) was investigated over a series of nanoparticle catalysts containing calcium, magnesium, potassium or nickel under mild reaction conditions. Nanoparticle catalyst samples were prepared from biowaste sources of chicken manure (CM), water hyacinth (WH) and algal bloom (AB), and characterized using XRD, Raman and FESEM techniques for the heterogeneous production of biodiesel. The catalyst was initially prepared by calcination at 850 °C for 4 h in a major presence of CaxMgyCO3, KCl and K2CO3. The WCO and AO co-conversion of 98% and FAMEs co-selectivity of 95% were obtained over CM nanoparticle catalyst under the reaction conditions of 80 °C, 20 mins and DMC to oil molar ratio of 6:1 with 3% catalyst loading and 3% methanol addition. Under the optimum condition, the density, viscosity, and cetane number of the biodiesel were in the range of diesel standards. Nanoparticle catalysts have been proven as a promising sustainable material in the catalytic transesterification of WCO and AO with the major presence of calcium, magnesium and potassium. This study highlights a sustainable approach via biowaste utilization for the enhancement of biodiesel quality with high ester content, low acid value, high cetane number, and low viscosity.

Using CO2 as an Oxidant in the Catalytic Pyrolysis of Peat Moss from the North Polar Region.

As global warming and climate change become perceived as significant, the release of greenhouse gases (GHGs) stored in the earth's polar regions is considered a matter of concern. Here, we focused on exploiting GHGs to address potential global warming challenges in the north polar regions. In particular, we used CO2 as a soft oxidant to recover energy as syngas (CO and H2) and to produce biochars from pyrolysis of peat moss. CO2 expedited homogeneous reaction with volatile matters from peat moss pyrolysis, and the mechanistic CO2 role resulted in the conversion of CO2 and peat moss to CO at ≥530 °C. Steel slag waste was then used as an ex situ catalyst to increase reaction kinetics, addressing the issue of the role of CO2 being limited to ≥530 °C, with the result where substantial H2 and CO formation was achieved at a milder temperature. The porosity of biochars, a solid peat moss pyrolysis product, was modified in the presence of CO2, with a significant improvement in CO2 adsorption capacity compared to those achieved by N2 pyrolysis. Therefore, CO2 has the potential to serve as an initial feedstock in sustainable biomass-to-energy applications and biochar production, mitigating atmospheric carbon concentrations.

Zeolite-Encaged Pd-Mn Nanocatalysts for CO2 Hydrogenation and Formic Acid Dehydrogenation.

A CO2 -mediated hydrogen storage energy cycle is a promising way to implement a hydrogen economy, but the exploration of efficient catalysts to achieve this process remains challenging. Herein, sub-nanometer Pd-Mn clusters were encaged within silicalite-1 (S-1) zeolites by a ligand-protected method under direct hydrothermal conditions. The obtained zeolite-encaged metallic nanocatalysts exhibited extraordinary catalytic activity and durability in both CO2 hydrogenation into formate and formic acid (FA) dehydrogenation back to CO2 and hydrogen. Thanks to the formation of ultrasmall metal clusters and the synergic effect of bimetallic components, the PdMn0.6 @S-1 catalyst afforded a formate generation rate of 2151 molformate molPd -1 h-1 at 353 K, and an initial turnover frequency of 6860 mol H 2 molPd -1 h-1 for CO-free FA decomposition at 333 K without any additive. Both values represent the top levels among state-of-the-art heterogeneous catalysts under similar conditions. This work demonstrates that zeolite-encaged metallic catalysts hold great promise to realize CO2 -mediated hydrogen energy cycles in the future that feature fast charge and release kinetics.

Localized Delivery of Pilocarpine to Hypofunctional Salivary Glands through Electrospun Nanofiber Mats: An Ex Vivo and In Vivo Study.

Dry mouth or xerostomia is a frequent medical condition among the polymedicated elderly population. Systemic pilocarpine is included in the first line of pharmacological therapies for xerostomia. However, the efficacy of existing pilocarpine formulations is limited due to its adverse side effects and multiple daily dosages. To overcome these drawbacks, a localized formulation of pilocarpine targeting the salivary glands (SG) was developed in the current study. The proposed formulation consisted of pilocarpine-loaded Poly(lactic-co-glycolic acid) (PLGA)/poly(ethylene glycol) (PEG) nanofiber mats via an electrospinning technique. The nanofiber mats were fully characterized for their size, mesh porosity, drug encapsulation efficiency, and in vitro drug release. Mat biocompatibility and efficacy was evaluated in the SG organ ex vivo, and the expression of proliferation and pro-apoptotic markers at the cellular level was determined. In vivo short-term studies were performed to evaluate the saliva secretion after acute SG treatment with pilocarpine-loaded nanofiber mats, and after systemic pilocarpine for comparison purposes. The outcomes demonstrated that the pilocarpine-loaded mats were uniformly distributed (diameter: 384 ± 124 nm) in a highly porous mesh, and possessed a high encapsulation efficiency (~81%). Drug release studies showed an initial pilocarpine release of 26% (4.5 h), followed by a gradual increase (~46%) over 15 d. Pilocarpine-loaded nanofiber mats supported SG growth with negligible cytotoxicity and normal cellular proliferation and homeostasis. Salivary secretion was significantly increased 4.5 h after intradermal SG treatment with drug-loaded nanofibers in vivo. Overall, this study highlights the strengths of PLGA/PEG nanofiber mats for the localized daily delivery of pilocarpine and reveals its potential for future clinical translation in patients with xerostomia.

Effective Recovery of Vanadium from Oil Refinery Waste into Vanadium-Based Metal-Organic Frameworks.

Carbon black waste, an oil refinery waste, contains a high concentration of vanadium(V) leftover from the processing of crude oil. For the sake of environmental sustainability, it is therefore of interest to recover the vanadium as useful products instead of disposing of it. In this work, V was recovered in the form of vanadium-based metal-organic frameworks (V-MOFs) via a novel pathway by using the leaching solution of carbon black waste instead of commercially available vanadium chemicals. Two different types of V-MOFs with high levels of crystallinity and phase purity were fabricated in very high yields (>98%) based on a coordination modulation method. The V-MOFs exhibited well-defined and controlled shapes such as nanofibers (length: > 10 µm) and nanorods (length: ∼270 nm). Furthermore, the V-MOFs showed high catalytic activities for the oxidation of benzyl alcohol to benzaldehyde, indicating the strong potential of the waste-derived V-MOFs in catalysis applications. Overall, our work offers a green synthesis pathway for the preparation of V-MOFs by using heavy metals of industrial waste as the metal source.

Codelivery of anti-cancer agents via double-walled polymeric microparticles/injectable hydrogel: A promising approach for treatment of triple negative breast cancer.

Triple negative breast cancer (TNBC) is an aggressive sub-type of breast cancer that rarely responds to conventional chemotherapy. Therefore, novel agents or new routes need to be developed to improve treatment efficacy and diminish severe side-effects of anti-cancer agents in TNBC patients. This study explores a novel localized co-delivery platform with potential application against TNBC. Uniform core-shell microparticles encapsulating cisplatin (Cis-DDP) and paclitaxel (PTX) are fabricated using coaxial electrohydrodynamic atomization technique and subsequently are embedded into an injectable hydrogel. The hydrogel provides an additional diffusion barrier against Cis-DDP and confines premature release of drugs. In addition, the hydrogel can provide a versatile tool for retaining particles in the tumor resected cavity during the injection following debulking surgery and prevent surgical site infection due to its inherent antibacterial properties. The combination of Cis-DDP and PTX demonstrates a synergistic effect against MDA-MB-231 cell line assigned to three different mechanisms of action, including denaturation of DNA strands, stabilization of microtubules, and amplification of intracellular reactive oxygen species (ROS) and activation of caspase-3 pathways. The results show a significant accumulation of mitochondrial ROS insults in cells upon treatment that consequently causes programmed cells death. The performance of microparticles/hydrogel carrier is evaluated against three-dimensional MDA-MB-231 (breast cancer) 3D spheroids, where a superior efficacy and a greater reduction in spheroid growth are observed over 14 days, as compared with free-drug treatment. Overall, drug-loaded core-shell microparticles embedded into injectable hydrogel provides a promising strategy to treat aggressive cancers and a modular platform for a broad range of localized multidrug therapies customizable to the cancer type.

Mathematical Modelling of Convection Enhanced Delivery of Carmustine and Paclitaxel for Brain Tumour Therapy.

PURPOSE: Convection enhanced delivery (CED) is a promising method of anticancer treatment to bypass the blood-brain barrier. This paper is aimed to study drug transport under different CED operating conditions. METHODS: The convection enhanced delivery of chemotherapeutics to an intact and a remnant brain tumour after resection is investigated by means of mathematical modelling of the key physical and physiological processes of drug transport. Realistic models of brain tumour and its holding tissue are reconstructed from magnetic resonance images. Mathematical modelling is performed for the delivery of carmustine and paclitaxel with different infusion rates, solution concentrations and locations of infusion site. RESULTS: Modelling predications show that drug penetration can be improved by raising the infusion rate and the infusion solution concentration. The delivery of carmustine with CED is highly localised. High drug concentration only can be achieved around the infusion site. The transport of paclitaxel is more sensitive to CED-enhanced interstitial fluid as compared to carmustine, with deeper penetration into tumour interior. Infusing paclitaxel in the upstream of interstitial fluid flow leads to high spatial averaged concentration and relatively uniform distribution. CONCLUSION: Results obtained in this study can be used to guide the design and optimisation of CED treatment regimens.

Enhanced intracellular delivery and controlled drug release of magnetic PLGA nanoparticles modified with transferrin.

Owing to the presence of multidrug resistance in tumor cells, conventional chemotherapy remains clinically intractable. To enhance the therapeutic efficacy of chemotherapeutic agents, targeting strategies based on magnetic polymeric nanoparticles modified with targeting ligands have gained significant attention in cancer therapy. In this study, we synthesized transferrin (Tf)-modified poly(D,L-lactic-co-glycolic acid) nanoparticles (PLGA NPs) loaded with paclitaxel (PTX) and superparamagnetic nanoparticle (MNP) using a solid-in-oil-in-water solvent evaporation method, followed by Tf adsorption on the surface of NPs. The Tf-modified magnetic PLGA NPs were characterized in terms of particle morphology and size, magnetic properties, encapsulation efficiency and drug release. Furthermore, the cytotoxicity and cellular uptake of the drug-loaded magnetic PLGA NPs were evaluated in both MCF-7 breast cancer and U-87 glioma cells in vitro. We found that Tf-modified PTX-MNP-PLGA NPs showed the highest cytotoxicity effect and cellular uptake efficiency under Tf receptor mediation in both MCF-7 and U-87 cells compared to unmodified PLGA NPs and free PTX. The cellular uptake efficiency of Tf-modified magnetic PLGA NPs appeared to be facilitated by the applied magnetic field, but the difference did not reach statistical significance. This study illustrates that this proposed formulation can be used as one new alternative treatment for patients bearing inaccessible tumors.

Bone morphogenetic protein-2 loaded poly(D,L-lactide-co-glycolide) microspheres enhance osteogenic potential of gelatin/hydroxyapatite/ß-tricalcium phosphate cryogel composite for alveolar ridge augmentation.

BACKGROUND/PURPOSE: Sufficient bony support is essential to ensure the success of dental implant osseointegration. However, the reconstruction of vertical ridge deficiencies is still a major challenge for dental implants. This study introduced a novel treatment strategy by infusing poly(D,L-lactide-co-glycolide) (PLGA) microspheres encapsulating bone morphogenetic protein-2 (BMP-2) within a gelatin/hydroxyapatite/ß-tricalcium phosphate (gelatin/HA/ß-TCP) cryogel composite to facilitate supra-alveolar ridge augmentation. METHODS: The gelatin scaffold was crosslinked using cryogel technique, and HA/ß-TCP particles were mechanically entrapped to form the gelatin/HA/ß-TCP composite. Co-axial electrohydrodynamic atomization technology was used to fabricate PLGA microspheres encapsulating BMP-2. The composites of gelatin/HA/ß-TCP alone, with infusion of BMP-2 solution (BMPi) or microspheres (BMPm), were fixed on rat mandibles using a titanium mini-implant for 4 weeks, and the therapeutic efficiency was evaluated by micro-computed tomography, bone fluorochrome, and histology. RESULTS: The gelatin/HA/ß-TCP composite was homogenously porous, and BMP-2 was sustained release from the microspheres without initial burst release. Ridge augmentation was noted in all specimens treated with the gelatin/HA/ß-TCP composite, and greater bone deposition ratio were noted in Groups BMPi and BMPm. Compared with Group BMPi, specimens in Group BMPm showed significantly greater early osteogenesis and evident osseointegration in the supra-alveolar level. CONCLUSION: BMP-2 loaded PLGA microspheres effectively promoted osteogenic potential of the gelatin/HA/ß-TCP composite and facilitated supra-alveolar ridge augmentation in vivo.

Potential application of gasification to recycle food waste and rehabilitate acidic soil from secondary forests on degraded land in Southeast Asia.

Gasification is recognized as a green technology as it can harness energy from biomass in the form of syngas without causing severe environmental impacts, yet producing valuable solid residues that can be utilized in other applications. In this study, the feasibility of co-gasification of woody biomass and food waste in different proportions was investigated using a fixed-bed downdraft gasifier. Subsequently, the capability of biochar derived from gasification of woody biomass in the rehabilitation of soil from tropical secondary forests on degraded land (adinandra belukar) was also explored through a water spinach cultivation study using soil-biochar mixtures of different ratios. Gasification of a 60:40 wood waste-food waste mixture (w/w) produced syngas with the highest lower heating value (LHV) 5.29 MJ/m(3)-approximately 0.4-4.0% higher than gasification of 70:30 or 80:20 mixtures, or pure wood waste. Meanwhile, water spinach cultivated in a 2:1 soil-biochar mixture exhibited the best growth performance in terms of height (a 4-fold increment), weight (a 10-fold increment) and leaf surface area (a 5-fold increment) after 8 weeks of cultivation, owing to the high porosity, surface area, nutrient content and alkalinity of biochar. It is concluded that gasification may be an alternative technology to food waste disposal through co-gasification with woody biomass, and that gasification derived biochar is suitable for use as an amendment for the nutrient-poor, acidic soil of adinandra belukar.

Local Sustained Delivery of 25-Hydroxyvitamin D3 for Production of Antimicrobial Peptides.

PURPOSE: This study seeks to develop fiber membranes for local sustained delivery of 25-hydroxyvitamin D3 to induce the expression and secretion of LL-37 at or near the surgical site, which provides a novel therapeutic approach to minimize the risk of infections. METHODS: 25-hydroxyvitamin D3 loaded poly(L-lactide) (PLA) and poly(ε-caprolactone) (PCL) fibers were produced by electrospinning. The morphology of obtained fibers was characterized using atomic force microscope (AFM) and scanning electron microscope (SEM). 25-hydroxyvitamin D3 releasing kinetics were quantified by enzyme-linked immunosorbent assay (ELISA) kit. The expression of cathelicidin (hCAP 18) and LL-37 was analyzed by immunofluorescence staining and ELISA kit. The antibacterial activity test was conducted by incubating pseudomonas aeruginosa in a monocytes' lysis solution. RESULTS: AFM images suggest that the surface of PCL fibers is smooth, however, the surface of PLA fibers is relatively rough, in particular, after encapsulation of 25-hydroxyvitamin D3. The duration of 25-hydroxyvitamin D3 release can last more than 4 weeks for all the tested samples. Plasma treatment can promote the release rate of 25-hydroxyvitamin D3. Human keratinocytes and monocytes express significantly higher levels of hCAP18/LL-37 after incubation with plasma treated and 25-hydroxyvitamin D3 loaded PCL fibers than the cells incubated with around ten times amount of free drug. After incubation with this fiber formulation for 5 days LL-37 in the lysis solutions of U937 cells can effectively kill the bacteria. CONCLUSIONS: Plasma treated and 25-hydroxyvitamin D3 loaded PCL fibers induce significantly higher levels of antimicrobial peptide production in human keratinocytes and monocytes without producing cytotoxicity.

Electrohydrodynamic atomization: A two-decade effort to produce and process micro-/nanoparticulate materials.

Electrohydrodynamic atomization (EHDA), also called electrospray technique, has been studied for more than one century. However, since 1990s it has begun to be used to produce and process micro-/nanostructured materials. Owing to the simplicity and flexibility in EHDA experimental setup, it has been successfully employed to generate particulate materials with controllable compositions, structures, sizes, morphologies, and shapes. EHDA has also been used to deposit micro- and nanoparticulate materials on surfaces in a well-controlled manner. All these attributes make EHDA a fascinating tool for preparing and assembling a wide range of micro- and nanostructured materials which have been exploited for use in pharmaceutics, food, and healthcare to name a few. Our goal is to review this field, which allows scientists and engineers to learn about the EHDA technique and how it might be used to create, process, and assemble micro-/nanoparticulate materials with unique and intriguing properties. We begin with a brief introduction to the mechanism and setup of EHDA technique. We then discuss issues critical to successful application of EHDA technique, including control of composition, size, shape, morphology, structure of particulate materials and their assembly. We also illustrate a few of the many potential applications of particulate materials, especially in the area of drug delivery and regenerative medicine. Next, we review the simulation and modeling of Taylor cone-jet formation for a single and co-axial nozzle. The mathematical modeling of particle transport and deposition is presented to provide a deeper understanding of the effective parameters in the preparation, collection and pattering processes. We conclude this article with a discussion on perspectives and future possibilities in this field.

Kinetic investigation on the catalytic pyrolysis of plastic fractions of waste electrical and electronic equipment (WEEE): A mathematical deconvolution approach.

Waste electrical and electronic equipment (WEEE) has become a critical environmental problem. Catalytic pyrolysis is an ideal technique to treat and convert the plastic fraction of WEEE into chemicals and fuels. Unfortunately, research using real WEEE remains relatively limited. Furthermore, the complexity of WEEE complicates the analysis of its pyrolytic kinetics. This study applied the Fraser-Suzuki mathematical deconvolution method to obtain the pseudo reactions of the thermal degradation of two types of WEEE, using four different catalysts (Al2O3, HBeta, HZSM-5, and TiO2) or without a catalyst. The main contributor(s) to each pseudo reaction were identified by comparing them with the pyrolysis results of the pure plastics in WEEE. The nth order model was then applied to estimate the kinetic parameters of the obtained pseudo reactions. In the low-grade electronics pyrolysis, the pseudo-1 reaction using TiO2 as a catalyst achieved the lowest activation energy of 92.10 kJ/mol, while the pseudo-2 reaction using HZSM-5 resulted in the lowest activation energy of 101.35 kJ/mol among the four catalytic cases. For medium-grade electronics, pseudo-3 and pseudo-4 were the main reactions for thermal degradation, with HZSM-5 and TiO2 yielding the lowest pyrolytic activation energies of 75.24 and 226.39 kJ/mol, respectively. This effort will play a crucial role in comprehending the pyrolysis kinetic mechanism of WEEE and propelling this technology toward a brighter future.

Controlling the proliferation and differentiation stages to initiate periodontal regeneration.

The success of periodontal regeneration depends on the coordination of early cell proliferation and late cell differentiation. The aim of this study was to investigate whether the proliferation or differentiation stage predominantly promotes the initiation of periodontal regeneration. Critical-sized periodontal defects were surgically created on rat maxillae and filled with poly-(D,L-lactide-co-glycolide)-poly-d,l-lactide hybrid microspheres encapsulating platelet-derived growth factor (PDGF, a promoter of mitogenesis), simvastatin (a promoter of osteogenic differentiation), or bovine serum albumin (a control). The encapsulation efficiency and in vitro release profiles of the microspheres were determined by high-performance liquid chromatography and enzyme-linked immunosorbent assay. The maxillae were harvested after 10 or 14 days and assessed by micro-computed tomography, histology, and immunohistochemistry for regeneration efficacy and cell viability. The rapid release of PDGF was observed within the first week, whereas a slow release profile was noted for simvastatin. The PDGF-treated specimens demonstrated a significantly higher bone volume fraction compared with bovine serum albumin- (p < 0.05) or simvastatin-treated (p < 0.05) specimens at day 14. Histologically, active bone formation originating from the defect borders was noted in both the PDGF- and the simvastatin-treated specimens, and functionally aligned periodontal ligament fiber insertion was only observed in the PDGF-treated specimens. The significant promotion of mitogenesis by PDGF treatment was also noted at day 14 (p < 0.05). In conclusion, increased mitogenesis or osteogenic differentiation may stimulate osteogenesis, and the upregulation of mitogenesis by PDGF appears to play a role in the initiation of periodontal regeneration.