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1 – 10 of 11Hakan Göcerler, Simon Medina, Michael Adler, Josef Brenner, Andreas Tadler, Michael Nagl and Christine Hohenadl
Dry eye syndrome is one of the most common reasons for eye-related discomfort which, without treatment, in some cases may even lead to corneal damage. Blinking, baseline and…
Abstract
Purpose
Dry eye syndrome is one of the most common reasons for eye-related discomfort which, without treatment, in some cases may even lead to corneal damage. Blinking, baseline and reflex lachrymation and drainage compromise the topical application of therapeutics demanding repeated, often hourly applications of common lubricants. In contrast, topically administered chitosan-N-acetylcysteine-based eye drops were reported to sustain on the ocular surface for more than 24 h. The thiolated biopolymer can interact with the corneal mucin layer thereby forming covalent disulphide bridges, which may contribute to extended residence times.
Design/methodology/approach
In this study, the tribological characteristics of four different lubricants including hyaluronic acid and chitosan-N-acetylcysteine containing commercially available eye drops were investigated. For this purpose, a representative test setup was developed, which mimics the contact between the cornea and the eyelid wiper. Gels with different elastic properties coated with a mucin layer were used as a substrate to mimic the corneal surface. Tests were conducted with a micro-tribometer, and friction values were recorded. Contact zones were characterized by X-ray photoelectron spectroscopy to investigate wear and thiol bonding on the surface.
Findings
Results revealed the lowest average coefficient of friction values for chitosan-N-acetylcysteine-based eye drops and substrate dependence of the test setup.
Originality/value
In this study, the authors introduced an in vitro system to test different types of eye drops so that chemical interaction with the mucin layer can be observed. These interactions change the tribological performance significantly and must be considered to have results relevant to the actual application.
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Fengyuan Liu, Srichand Hinduja and Paulo Bártolo
This paper aims to describe the control software of a novel manufacturing system called plasma-assisted bio-extrusion system (PABS), designed to produce complex multi-material and…
Abstract
Purpose
This paper aims to describe the control software of a novel manufacturing system called plasma-assisted bio-extrusion system (PABS), designed to produce complex multi-material and functionally graded scaffolds for tissue engineering applications. This fabrication system combines multiple pressure-assisted and screw-assisted printing heads and plasma jets. Control software allows the users to create single or multi-material constructs with uniform pore size or pore size gradients by changing the operation parameters, such as geometric parameters, lay-down pattern, filament distance, feed rate and layer thickness, and to produce functional graded scaffolds with different layer-by-layer coating/surface modification strategies by using the plasma modification system.
Design/methodology/approach
MATLAB GUI is used to develop the software, including the design of the user interface and the implementation of all mathematical programing for both multi-extrusion and plasma modification systems.
Findings
Based on the user definition, G programing codes are generated, enabling full integration and synchronization with the hardware of PABS. Single, multi-material and functionally graded scaffolds can be obtained by manipulating different materials, scaffold designs and processing parameters. The software is easy to use, allowing the efficient control of the PABS even for the fabrication of complex scaffolds.
Originality/value
This paper introduces a novel additive manufacturing system for tissue engineering applications describing in detail the software developed to control the system. This new fabrication system represents a step forward regarding the current state-of-the-art technology in the field of biomanufacturing, enabling the design and fabrication of more effective scaffolds matching the mechanical and surface characteristics of the surrounding tissue and enabling the incorporation of high number of cells uniformly distributed and the introduction of multiple cell types with positional specificity.
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Rana I. Mahmood, Harraa S. Mohammed-Salih, Ata’a Ghazi, Hikmat J. Abdulbaqi and Jameel R. Al-Obaidi
In the developing field of nano-materials synthesis, copper oxide nanoparticles (NPs) are deemed to be one of the most significant transition metal oxides because of their…
Abstract
Purpose
In the developing field of nano-materials synthesis, copper oxide nanoparticles (NPs) are deemed to be one of the most significant transition metal oxides because of their intriguing characteristics. Its synthesis employing green chemistry principles has become a key source for next-generation antibiotics attributed to its features such as environmental friendliness, ease of use and affordability. Because they are more environmentally benign, plants have been employed to create metallic NPs. These plant extracts serve as capping, stabilising or hydrolytic agents and enable a regulated synthesis as well.
Design/methodology/approach
Organic chemical solvents are harmful and entail intense conditions during nanoparticle synthesis. The copper oxide NPs (CuO-NPs) synthesised by employing the green chemistry principle showed potential antitumor properties. Green synthesised CuO-NPs are regarded to be a strong contender for applications in the pharmacological, biomedical and environmental fields.
Findings
The aim of this study is to evaluate the anticancer potential of CuO-NPs plant extracts to isolate and characterise the active anticancer principles as well as to yield more effective, affordable, and safer cancer therapies.
Originality/value
This review article highlights the copper oxide nanoparticle's biomedical applications such as anticancer, antimicrobial, dental and drug delivery properties, future research perspectives and direction are also discussed.
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Uchenna Luvia Ezeamaku, Chinyere Ezekannagha, Ochiagha I. Eze, Nkiru Odimegwu, Angela Nwakaudu, Amarachukwu Okafor, Innocent Ekuma and Okechukwu Dominic Onukwuli
The impact of potassium permanganate (KMnO4) treatment on the tensile strength of an alkali-treated pineapple leaf fiber (PALF) reinforced with tapioca-based bio resin (cassava…
Abstract
Purpose
The impact of potassium permanganate (KMnO4) treatment on the tensile strength of an alkali-treated pineapple leaf fiber (PALF) reinforced with tapioca-based bio resin (cassava starch) was studied.
Design/methodology/approach
The PALF was exposed to sodium hydroxide (NaOH) treatment in varying concentrations of 2.0, 3.7, 4.5 and 5.5g prior to the fiber treatment with KMnO4. The treated and untreated PALFs were reinforced with tapioca-based bio resin. Subsequently, they were subjected to Fourier transform infrared (FTIR) and tensile test analysis.
Findings
The FTIR analysis of untreated PALF revealed the presence of O-H stretch, N-H stretch, C=O stretch, C=O stretch and H-C-H bond. The tensile test result confirmed the highest tensile strength of 35N from fiber that was reinforced with 32.5g of cassava starch and treated with 1.1g of KMnO4. In comparison, the lowest tensile strength of 15N was recorded for fiber reinforced with 32.5g of cassava starch without KMnO4 treatment.
Originality/value
Based on the results, it could be deduced that despite the enhancement of bioresin (cassava starch) towards strength-impacting on the fibers, KMnO4 treatment on PALF is very vital for improved tensile strength of the fiber when compared to untreated fibers. Hence, KMnO4 treatment on alkali-treated natural fibers preceding reinforcement is imperative for bio-based fibers.
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Biniam Tekle Teweldebrhan, Praveen Maghelal and Abdulla Galadari
Although additive manufacturing (AM; 3D printing/3DP) is presently in its infancy, once it becomes economically viable for mass production, it would revolutionize the operation…
Abstract
Purpose
Although additive manufacturing (AM; 3D printing/3DP) is presently in its infancy, once it becomes economically viable for mass production, it would revolutionize the operation and supply chain network of traditional businesses and manufacturing industries. To this end, approaches for ensuring a smooth transition of the economy, businesses, manufacturing centers and related services are being investigated. This review paper assesses the existing literature on the impact of AM on the maritime transportation sector.
Design/methodology/approach
This paper provides a systematic literature review through three methodological phases: (1) a comprehensive review of the number of English language literature studies published on the topics of AM or 3DP (1970–2021); (2) a bibliometric analysis of selected keyword combinations and (3) a detailed review on the impact of AM on different sectors.
Findings
The key findings are that existing studies do not attempt to forecast shipping volume and ton-miles that can be affected by the mainstreaming of the technology. Additionally, existing literature that focuses on the impact of the technology on different shipping categories is limited to studies on container ships.
Originality/value
The review identifies some potential areas of research that since maritime transportation will be affected by mainstreaming AM, it will have economic, social and environmental impacts on global trade that require future assessment.
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Zrinka Buhin Šturlić, Mirela Leskovac, Krunoslav Žižek and Sanja Lučić Blagojević
The purpose of this paper is to prepare stabile emulsions with 0–15% of colloidal silica and high monomer/water ratio and to investigate the influence of silica addition and…
Abstract
Purpose
The purpose of this paper is to prepare stabile emulsions with 0–15% of colloidal silica and high monomer/water ratio and to investigate the influence of silica addition and surface modification on the polyacrylate properties.
Design/methodology/approach
Improving the properties of the composite can be achieved by optimizing the compatibility between the phases of the composite system with improving the interactions at the matrix/filler interface. Therefore, the silica surface was modified with nonionic emulsifier octylphenol ethoxylate, cationic initiator 2,2'-azobis-(amidinopropane dihydrochloride) and 3-methacryloxypropyltrimethoxysilane and polyacrylate/silica nanocomposites were prepared via in situ emulsion polymerization. Particle size distribution, rheological properties of the emulsions and morphology, thermal properties and mechanical properties of the film prepared from the emulsions were investigated.
Findings
Polyacrylate/silica systems with unmodified silica, silica modified with nonionic emulsifier and cationic initiator have micrometer, while pure PA matrix and systems with silica modified with silane have nanometer particle sizes. Addition and surface modification of the filler increased emulsion viscosity. Agglomeration of silica particles in composites was reduced with silica surface modification. Silica filler improves thermal stability and tensile strength of polyacrylate.
Originality/value
This paper provides broad spectrum of information depending on filler surface modification and latex preparation via in situ emulsion polymerization and properties with high amount of filler and monomer/water ratio with the aim that prepared latex is suitable for film formation and final application.
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Subhamoy Dhua, Kshitiz Kumar, Vijay Singh Sharanagat and Prabhat K. Nema
The amount of food wasted every year is 1.3 billion metric tonne (MT), out of which 0.5 billion MT is contributed by the fruits processing industries. The waste includes…
Abstract
Purpose
The amount of food wasted every year is 1.3 billion metric tonne (MT), out of which 0.5 billion MT is contributed by the fruits processing industries. The waste includes by-products such as peels, pomace and seeds and is a good source of bioactive compounds like phenolic compounds, flavonoids, pectin lipids and dietary fibres. Hence, the purpose of the present study is to review the novel extraction techniques used for the extraction of the bio active compounds from food waste for the selection of suitable extraction method.
Design/methodology/approach
Novel extraction techniques such as ultrasound-assisted extraction, microwave-assisted extraction, enzyme-assisted extraction, supercritical fluid extraction, pulsed electric field extraction and pressurized liquid extraction have emerged to overcome the drawbacks and constraints of conventional extraction techniques. Hence, this study is focussed on novel extraction techniques, their limitations and optimization for the extraction of bioactive compounds from fruit and vegetable waste.
Findings
This study presents a comprehensive review on the novel extraction processes that have been adopted for the extraction of bioactive compounds from food waste. This paper also summarizes bioactive compounds' optimum extraction condition from various food waste using novel extraction techniques.
Research limitations/implications
Food waste is rich in bioactive compounds, and its efficient extraction may add value to the food processing industries. Hence, compressive analysis is needed to overcome the problem associated with the extraction and selection of suitable extraction techniques.
Social implications
Selection of a suitable extraction method will not only add value to food waste but also reduce waste dumping and the cost of bioactive compounds.
Originality/value
This paper presents the research progress on the extraction of bioactive active compounds from food waste using novel extraction techniques.
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Yee Vern Ng, Tengku Alina Tengku Ismail and Wan Rosli Wan Ishak
Demand for dietary fibre-enriched and low sugar bakery products is increasing rapidly due to current high incidence of type 2 diabetes mellitus. Overripe banana has been discarded…
Abstract
Purpose
Demand for dietary fibre-enriched and low sugar bakery products is increasing rapidly due to current high incidence of type 2 diabetes mellitus. Overripe banana has been discarded due to its low quality and appearance. However, overripe banana exhibits rich sources of natural sweetener and dietary fibre which could potentially be used as a novel food ingredient in bakery product. Thus, the study aims to determine the nutritional properties, sensory acceptability and glycaemic index (GI) value of chocolate cookies formulated with overripe banana sweetener (OBS) as partial replacement (10, 15 and 20%) for table sugar and utilization of overripe banana residue (OBR) as partial replacement (8%) for wheat flour.
Design/methodology/approach
Nutritional composition was analysed using AOAC methods and sensory acceptability using 7-point hedonic scaling method. In Vivo GI determination was continued according to FAO/WHO method.
Findings
Incorporation of OBR and OBS significantly (p < 0.05) increased nutritional values of chocolate cookies. Chocolate cookies formulated with 8% OBR +20% OBS recorded the highest TDF (7.80%) and ash (1.47%) content. Sucrose content of chocolate cookies was reduced significantly with increasing level of OBS. Sensory scores for control and 8% OBR-incorporated cookie were not significant difference for all the sensory attributes. Moreover, incorporation of OBS up to 15% produced higher scores in term of aroma, flavour and overall acceptance. Three formulations of chocolate cookies (control, 8% OBR and 8% OBR +15% OBS) were selected for GI testing and recorded GI values of 63, 56 and 50, respectively.
Originality/value
Overripe banana can be used as a food ingredient in developing high fibre and low-GI cookie.
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