Advanced engineering of Fibrous Non-steroidal anti-inflammatory drug (NSAID) films for buccal application using Electrohydrodynamic Atomisation

The development of therapeutic dosage (e.g. pharmaceutical) systems is an ongoing process which, in recent times has incorporated several emerging disciplines and themes at timely intervals. While the concepts surrounding dosages have developed and evolved, many polymeric excipients remain as the preferred choice of materials over existing counterparts, serving functions as matrix materials, coatings and providing other specific functional properties (e.g. adhesion, controlled release and mechanical properties). Therefore, polymer is employed as a matrix carrier of materials or as active release performance modulating agents for polymeric based dosages. There have been, however, developments in the deployment of synthetic polymeric materials (e.g. polycaprolactone, poly lactic co-glycolic acid) when compared to naturally occurring materials (e.g. lactose, gelatin). Additionally, numerous techniques have been advanced further to novel engineering polymeric structures which provide materials in micrometer to nanometer scale range. Some of these structures enabling technologies include spray drying, super critical processing, microfluidics and even wet chemical methods. Recently maturing processes which is operational at the ambient environment is electrohydrodynamic (EHDA) engineering methods (ES and ESy). They have emerged as robust technologies offering potential to fabricate a plethora of generic structures directly into a fibrous polymer matrix system (e.g. particles, fibres, bubbles and pre-determined patterns) on a broad scale range. This research focuses on key developments using EHDA technology for the pharmaceutical and biomaterial remits when selecting synthetic and/or naturally occurring polymers as pharmaceutical (and therapeutic) excipients. EHDA was employed to engineer NSAID drugs in fibre film form for buccal delivery. EHDA was selected to develop fibre film of Indomethacin, Diclofenac Sodium, Ketoprofen, and Piroxicam in cooperation of PVP, Ethocel, Methocel, HPMC, and Tween 80. Morphology of electrospun films were analyzed by SEM and further characterized using DSC, TGA, FTIR, Raman and XRD. DSC and XRD demonstrated NSAID drugs change from crystalline to amorphous state. FTIR and Raman data suggest NSAID, PVP and co-polymers (Methocel™ E5, Methocel™ E15 Ethocel™ E10, HMPC and Tween® 80) were integrated in stable fashion into filamentous structures via ES. The release behaviour from several matrixes that was observed suggesting a potential route to modify drug release based on polymeric excipients. Therefore, identifying co-polymers in matrix and their effect in vitro release was the main core of chapter 3. Based on the results (fast or slow release), the co-polymer was incorporated with several NSAID drugs. However, each NSAID drugs show different release behaviour with same co-polymer. In addition, the underlying EHDA process principles are discussed along with key parameters and variables (both materials and engineering). EHDA technologies are operational at ambient conditions and recent developments have also demonstrated their viability for large scale production. These are promising technologies which have potential in established (e.g. films, dressings and microparticles) and emerging scientific themes (e.g. nanomedicines and tissue engineering). Moreover, EHDA a one-step process facilitates us to optimise dosage forms as desirable in a single step for several age groups. The use of EHDA need to be more explored within the buccal research concern. It has shown great potential in this research concept; therefore, it is viable to pursue to wider area in this field

A Novel Hybrid Framework for Co-Optimization of Power and Natural Gas Networks Integrated With Emerging Technologies

In a power system with high penetration of renewable power sources, gas-fired units can be considered as a back-up option to improve the balance between generation and consumption in short-term scheduling. Therefore, closer coordination between power and natural gas systems is anticipated. This article presents a novel hybrid information gap decision theory (IGDT)-stochastic cooptimization problem for integrating electricity and natural gas networks to minimize total operation cost with the penetration of wind energy. The proposed model considers not only the uncertainties regarding electrical load demand and wind power output, but also the uncertainties of gas load demands for the residential consumers. The uncertainties of electric load and wind power are handled through a scenario-based approach, and residential gas load uncertainty is handled via IGDT approach with no need for the probability density function. The introduced hybrid model enables the system operator to consider the advantages of both approaches simultaneously. The impact of gas load uncertainty associated with the residential consumers is more significant on the power dispatch of gas-fired plants and power system operation cost since residential gas load demands are prior than gas load demands of gas-fired units. The proposed framework is a bilevel problem that can be reduced to a one-level problem. Also, it can be solved by the implementation of a simple concept without the need for Karush–Kuhn–Tucker conditions. Moreover, emerging flexible energy sources such as the power to gas technology and demand response program are considered in the proposed model for increasing the wind power dispatch, decreasing the total operation cost of the integrated network as well as reducing the effect of system uncertainties on the total operating cost. Numerical results indicate the applicability and effectiveness of the proposed model under different working conditions

Impacts of Logging-Associated Compaction on Forest Soils: A Meta-Analysis

Soil compaction associated with mechanized wood harvesting can long-lastingly disturb forest soils, ecosystem function, and productivity. Sustainable forest management requires precise and deep knowledge of logging operation impacts on forest soils, which can be attained by meta-analysis studies covering representative forest datasets. We performed a meta-analysis on the impact of logging-associated compaction on forest soils microbial biomass carbon (MBC), bulk density, total porosity, and saturated hydraulic conductivity (Ksat) affected by two management factors (machine weight and passage frequency), two soil factors (texture and depth), and the time passed since the compaction event. Compaction significantly decreased soil MBC by −29.5% only in subsoils (>30 cm). Overall, compaction increased soil bulk density by 8.9% and reduced total porosity and Ksat by −10.1 and −40.2%, respectively. The most striking finding of this meta-analysis is that the greatest disturbance to soil bulk density, total porosity, and Ksat occurs after very frequent (>20) machine passages. This contradicts the existing claims that most damage to forest soils happens after a few machine passages. Furthermore, the analyzed physical variables did not recover to the normal level within a period of 3–6 years. Thus, altering these physical properties can disturb forest ecosystem function and productivity, because they play important roles in water and air supply as well as in biogeochemical cycling in forest ecosystems. To minimize the impact, we recommend the selection of suitable logging machines and decreasing the frequency of machine passages as well as logging out of rainy seasons especially in clayey soils. It is also very important to minimize total skid trail coverage for sustainable forest management

Network-constrained joint energy and flexible ramping reserve market clearing of power- and heat-based energy systems : a two-stage hybrid IGDT-stochastic framework

This article proposes a new two-stage hybrid stochastic–information gap-decision theory (IGDT) based on the network-constrained unit commitment framework. The model is applied for the market clearing of joint energy and flexible ramping reserve in integrated heat- and power-based energy systems. The uncertainties of load demands and wind power generation are studied using the Monte Carlo simulation method and IGDT, respectively. The proposed model considers both risk-averse and risk-seeker strategies, which enables the independent system operator to provide flexible decisions in meeting system uncertainties in real-time dispatch. Moreover, the effect of feasible operating regions of the combined heat and power (CHP) plants on energy and flexible ramping reserve market and operation cost of the system is investigated. The proposed model is implemented on a test system to verify the effectiveness of the introduced two-stage hybrid framework. The analysis of the obtained results demonstrates that the variation of heat demand is effective on power and flexible ramping reserve supplied by CHP units.©2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.fi=vertaisarvioitu|en=peerReviewed

Keeping thinning-derived deadwood logs on forest floor improves soil organic carbon, microbial biomass, and enzyme activity in a temperate spruce forest

Deadwood is a key component of forest ecosystems, but there is limited information on how it influences forest soils. Moreover, studies on the effect of thinning-derived deadwood logs on forest soil properties are lacking. This study aimed to investigate the impact of thinning-derived deadwood logs on the soil chemical and microbial properties of a managed spruce forest on a loamy sand Podzol in Bavaria, Germany, after about 15 years. Deadwood increased the soil organic carbon contents by 59% and 56% at 0–4 cm and 8–12 cm depths, respectively. Under deadwood, the soil dissolved organic carbon and carbon to nitrogen ratio increased by 66% and 15% at 0–4 cm depth and by 55% and 28% at 8–12 cm depth, respectively. Deadwood also induced 71% and 92% higher microbial biomass carbon, 106% and 125% higher microbial biomass nitrogen, and 136% and 44% higher β-glucosidase activity in the soil at 0–4 cm and 8–12 cm depths, respectively. Many of the measured variables significantly correlated with soil organic carbon suggesting that deadwood modified the soil biochemical processes by altering soil carbon storage. Our results indicate the potential of thinned spruce deadwood logs to sequester carbon and improve the fertility of Podzol soils. This could be associated with the slow decay rate of spruce deadwood logs and low biological activity of Podzols that promote the accumulation of soil carbon. We propose that leaving thinning-derived deadwood on the forest floor can support soil and forest sustainability as well as carbon sequestration

Quality by design micro-engineering optimisation of NSAID-loaded electrospun fibrous patches

The purpose of this study was to apply the Quality by Design (QbD) approach to the electrospinning of fibres loaded with the nonsteroidal anti-inflammatory drugs (NSAIDs) indomethacin (INDO) and diclofenac sodium (DICLO). A Quality Target Product Profile (QTPP) was made, and risk assessments (preliminary hazard analysis) were conducted to identify the impact of material attributes and process parameters on the critical quality attributes (CQAs) of the fibres. A full factorial design of experiments (DoE) of 20 runs was built, which was used to carry out experiments. The following factors were assessed: Drugs, voltage, flow rate, and the distance between the processing needle and collector. Release studies exhibited INDO fibres had greater total release of active drug compared to DICLO fibres. Voltage and distance were found to be the most significant factors of the experiment. Multivariate statistical analytical software helped to build six feasible design spaces and two flexible, universal design spaces for both drugs, at distances of 5 cm and 12.5 cm, along with a flexible control strategy. The current findings and their analysis confirm that QbD is a viable and invaluable tool to enhance product and process understanding of electrospinning for the assurance of high-quality fibres

Evaluation of hydrogen storage technology in risk-constrained stochastic scheduling of multi-carrier energy systems considering power, gas and heating network constraints

The operation of energy systems considering a multi-carrier scheme takes several advantages of economical, environmental, and technical aspects by utilizing alternative options is supplying different kinds of loads such as heat, gas, and power. This study aims to evaluate the influence of power to hydrogen conversion capability and hydrogen storage technology in energy systems with gas, power, and heat carriers concerning risk analysis. Accordingly, conditional value at risk (CVaR)-based stochastic method is adopted for investigating the uncertainty associated with wind power production. Hydrogen storage system, which can convert power to hydrogen in off-peak hours and to feed generators to produce power at on-peak time intervals, is studied as an effective solution to mitigate the wind power curtailment because of high penetration of wind turbines in electricity networks. Besides, the effect constraints associated with gas and district heating network on the operation of the multi-carrier energy systems has been investigated. A gas-fired combined heat and power (CHP) plant and hydrogen storage are considered as the interconnections among power, gas and heat systems. The proposed framework is implemented on a system to verify the effectiveness of the model. The obtained results show the effectiveness of the model in terms of handling the risks associated with multi-carrier system parameters as well as dealing with the penetration of renewable resources

Evaluating the Impact of Multi-Carrier Energy Storage Systems in Optimal Operation of Integrated Electricity, Gas and District Heating Networks

Various energy networks such as electricity, natural gas, and district heating can be connected by emerging technologies for efficient application of renewable energy sources. On the other hand, the pressure shortage in the natural gas network and increasing heat loss in the district heating network by growth of gas and heat load in winter might play a significant role in the participation of combined heat and power units in the energy markets and operation cost of the whole integrated energy system. Hence, this paper presents a multi-network constrained unit commitment problem in the presence of multi-carrier energy storage technologies aiming to minimize the operation cost of an integrated electricity, gas and district heating system while satisfying the constraints of all three networks. In addition, an information gap decision theory is developed for studying the uncertainty of energy sources under risk-seeker and risk-averse strategies with no need for probability distribution function. Moreover, the role of multi-carrier energy storage technologies in integrated networks is investigated, which indicates decrement of total operation cost and reduction of the effect of wind power uncertainty on total operation cost in presence of the storage technologies

In Vitro and Ex Vivo Evaluation of Tablets Containing Piroxicam-Cyclodextrin Complexes for Buccal Delivery

In the current study, the development of mucoadhesive tablets for buccal delivery of a non-steroidal anti-inflammatory drug was investigated. Binary complexes with piroxicam and cyclodextrins (beta-cyclodextrin (b-CD), methylated-beta-cyclodextrin (Me-b-CD), and hydroxypropyl-beta-cyclodextrin (HP-b-CD)) were prepared by the co-evaporation method. All formulations were characterized by means of diferential scanning calorimetry, infrared spectroscopy and powder X-ray diffractometry. Mucoadhesive tablets of binary systems were formulated by direct compression using chitosan as mucoadhesive polymer. The in vitro release profiles of tablets were conducted in simulated saliva and, the drug permeation studies, across porcine buccal mucosa. The results suggest that the rank order effect of cyclodextrins for the drug release was Me-b-CD >HP-b-CD > b-CD, whereas the ex vivo studies showed that the tablets containing chitosan significantly increased the transport of the drug compared to their free complexes. Finally, histological assessment revealed loss of the superficial cell layers, which might be attributed to the presence of cyclodextrins