Development of a low-cost biomedical device to enhance pneumonia diagnosis in children

This is the Accepted Manuscript version of this article which has been accepted for publication and will appear in a revised form, subsequent to peer review and/or editorial input by Materials Research Society or Cambridge University Press, in MRS Advances published by Materials Research Society and Cambridge University Press, together with a copyright notice in the name of the copyright holder (Materials Research Society). On publication, the full bibliographical details of the article (volume: issue number (date), page numbers) will be inserted after the journal-title, together with a link to the Cambridge website address for the JournalPneumonia has contributed greatly to child mortality, especially among children under the ages of five in sub-Saharan Africa, killing more children than the number of children dying from HIV/AIDS. The current methods of diagnosing pneumonia involved physical examination and chest x-ray which are limited by low accuracy, high error margins, higher cost, and stands the risks of inducing cancer. In this work, a low-cost, non-invasive biomedical device was designed and developed to improve accuracy in diagnosing pneumonia. The device functions to detect fluid in a lung consolidated by pneumonia. Dry grouting sponge was used as a phantom for a healthy lung, while a wet sponge was used to mimic a pneumoniaconsolidated lung. Surface exciter was used to produce sound waves which travelled through one side of the phantom and are detected on the other end using an electronic stethoscope. The signals detected were digitally analyzed using MATLAB and AUDACITY software. The differences in resonant frequencies from the power spectrum analysis of sound waves as they travelled through the sponges were used to distinguish between a pneumonia-consolidated lung and a healthy lung.Ashesi Universit

Recycling of plastic waste materials: Mechanical properties and implications for road construction

This is the Accepted Manuscript version of this article which has been accepted for publication and will appear in a revised form, subsequent to peer review and/or editorial input by Materials Research Society or Cambridge University Press, in MRS Advances published by Materials Research Society and Cambridge University Press, together with a copyright notice in the name of the copyright holder (Materials Research Society). On publication, the full bibliographical details of the article (volume: issue number (date), page numbers) will be inserted after the journal-title, together with a link to the Cambridge website address for the JournalThis paper presents a recent study on recycling poly-ethylene-tetraphylate (PET), known as plastic waste material in Ghana, to wealth. Composites were produced by heating aggregates together with shredded PET plastic waste material, while bitumen was added to the plasticcoated aggregates. The composites produced were reinforced with 4.5 wt%, 9.0 wt%, 13.6 wt%, and 18.0 wt% PET. Mechanical properties of the fabricated composite samples were studied with a Universal testing machine for optimization. The work demonstrated that shredded PET plastic waste material acts as a strong binding agent for bitumen that can improve on the shelf life of the asphalt. From the results, 13.6 wt% concentration of PET was shown to experience the maximum compressive strength and flexural strength. Besides, water resistance was shown to increase with PET concentrations/weight fraction. From the data characterized 13.6 wt% of PET plastic gives the optimum plastic concentration that enhances the rheological properties of bitumen. The implications of the result are therefore discussed for the use of 13.6 wt% PET in road construction.Ashesi Universit

Mechanical characterization of earth-based composites materials reinforced with treated bamboo fibres for affordable housing

This is the Accepted Manuscript version of this article which has been accepted for publication and will appear in a revised form, subsequent to peer review and/or editorial input by Materials Research Society or Cambridge University Press, in MRS Advances published by Materials Research Society and Cambridge University Press, together with a copyright notice in the name of the copyright holder (Materials Research Society). On publication, the full bibliographical details of the article (volume: issue number (date), page numbers) will be inserted after the journal-title, together with a link to the Cambridge website address for the Journal.This paper presents the characterization of laterite-cement-based matrix composites, reinforced with chemically modified bamboo fibers. Fiber extraction and chemical modification were first explored by soaking slabs of bamboos in NaOH solution (5 wt.% of NaOH in distilled water) for 14 days. Fiber characterization, as well as the flexural and compressive strength of reinforced composites, were carried out with MTS universal mechanical testing machine. Comparative results on the compressive and flexural strength were obtained at 80 wt.% laterite (L) to 20 wt.% cement (C) with fiber ratios from 5-25 wt%. The compressive strength of the composites varied from 7.2 MPa (at 5 wt.% bamboo fiber) to 17.67 MPa (at 25 wt% fiber blocks). The hardness of the composites was found to improve from 66.67-75.0 HD with bamboo fibers. Results were then discussed for possible structural applications such as enhancing low-cost building blocks for rural communities in Ghana.Ashesi Universit

Uniaxial tensile response of coconut coir fiber-reinforced polyethylene Composites

The roles of Composite materials in a variety of engineering applications have increased due to their enhanced strength and modulus, especially polymer-based composites which is one of the commercially available composites. The uniaxial tensile properties of polyethylene matrix reinforced with coconut coir fibers has been studied and the results from experiments and analytical models are presented. The compositional dependence of tensile strength, stiffness (elastic modulus), modulus of resilience and ductility are explored for different proportions of the constituent materials through experiments and analytical models. The results from experiments showed that the properties measured were greatly affected by the fiber mass fraction with optimized properties obtained at fiber content of 10 wt%

Uniaxial tensile response of coconut coir fiber-reinforced polyethylene Composites

The roles of Composite materials in a variety of engineering applications have increased due to their enhanced strength and modulus, especially polymer-based composites which is one of the commercially available composites. The uniaxial tensile properties of polyethylene matrix reinforced with coconut coir fibers has been studied and the results from experiments and analytical models are presented. The compositional dependence of tensile strength, stiffness (elastic modulus), modulus of resilience and ductility are explored for different proportions of the constituent materials through experiments and analytical models. The results from experiments showed that the properties measured were greatly affected by the fiber mass fraction with optimized properties obtained at fiber content of 10 wt%

Uniaxial tensile response of coconut coir fiber-reinforced polyethylene Composites

The roles of Composite materials in a variety of engineering applications have increased due to their enhanced strength and modulus, especially polymer-based composites which is one of the commercially available composites. The uniaxial tensile properties of polyethylene matrix reinforced with coconut coir fibers has been studied and the results from experiments and analytical models are presented. The compositional dependence of tensile strength, stiffness (elastic modulus), modulus of resilience and ductility are explored for different proportions of the constituent materials through experiments and analytical models. The results from experiments showed that the properties measured were greatly affected by the fiber mass fraction with optimized properties obtained at fiber content of 10 wt%

Effect of Chemically Modified Banana Fibers on the Mechanical Properties of Poly-Dimethyl-Siloxane-Based Composites

The study presents the mechanical properties of polymer-based composites reinforced with chemically modified banana fibers, by alkalization in different concentrations of sodium hydroxide (NaOH). The fiber weight fraction has a great effect on the mechanical properties of the composites. Stiff composites were obtained at 6 wt% fiber fractions with Young’s modulus of 254.00 ±12.70 MPa. Moreover, the yield strength was 35.70 ±1.79 MPa at 6 wt% fiber fractions. However, the ultimate tensile strength (UTS) and toughness of the composites were obtained at 5 wt% fiber fractions. Statistical analyses were used to ascertain the significant different on the mechanical properties of the fibers and composites. The implication of the results is then discussed for potential applications of PDMS-based composites reinforced with chemically modified banana fibers

Laser application of nanocomposite hydrogels on cancer cell viability

This is the Accepted Manuscript version of this article which has been accepted for publication and will appear in a revised form, subsequent to peer review and/or editorial input by Materials Research Society or Cambridge University Press, in MRS Advances published by Materials Research Society and Cambridge University Press, together with a copyright notice in the name of the copyright holder (Materials Research Society). On publication, the full bibliographical details of the article (volume: issue number (date), page numbers) will be inserted after the journal-title, together with a link to the Cambridge website address for the JournalNanocomposite hydrogels of poly-n-isopropyl were prepared by incorporating gold and magnetite nanoparticles. The nanocomposite-based hydrogels formed were geometrical, ~7.3 mm in diameter and 5 mm thick (in the swollen state). Morphological analysis was characterized by a scanning electron microscope. Drug-loaded hydrogels were subjected to laser heating at 1 W, 1.5 W and 2 W for 20 min in each laser cycle. The metabolic activities of the cells were analysed. The photothermal conversion efficiency of the nanocomposite hydrogels was also evaluated for P(NIPA)-AuNP-PG and P(NIPA)-MNP-PG to be 36.93 and 32.57 %, respectively. The result was then discussed for potential applications whereby metalbased hydrogels can be employed in microfluidic devices for targeted cancer drug delivery.Pan-African Materials Institute (PAMI) (Grant No. P126974) - funding. Ashesi University, Ghana Worcester Polytechnic Institute (WPI) US

Effect of particle size and sintering time on the mechanical properties of porous Ti–6Al–4V implant

Titanium alloys have been extensively used in biomedical applications owing to its low density, excellent biocompatibility (i.e., biological and chemical inertness), and unique mechanical properties. However, there is a high disparity between Young’s moduli of the implant and the natural bone. This disparity causes stress shielding in the body. This paper presents the effect of particle size and sintering time of Ti–6Al–4V powder used in the formation of a porous implant, sintered at 980 °C. Morphological characteristics of the sintered samples were obtained with a scanning electron microscope. The effect of surface hydrophilicity of the samples was elucidated via surface wettability testing using contact angle measurement with bio-fluid. Mechanical characterization was also evaluated with nanoindentation and a universal testing machine. The relation between Young’s modulus and sintering time was presented. It was observed that the wettability decreases with sintering time and the Ti alloy powder with particle size < 150 µm had the Young’s modulus that is closer to the modulus of the bone; the optimum sintering time was 5 h.Petroleum Technology Development Fund (PTDF), Pan African Materials Institute (PAMI), African University of Science and Technology, Abuja

Abstract C60: Injectable, biodegradable micro- and nano-particles loaded with prodigiosin-based drug for localized anticancer drug delivery

This paper presents the synthesis and physicochemical characterization of injectable, multi-functional, biodegradable poly (D,L-lactide-co-glycolide) (PLGA)-loaded micro- and nano-particles. These particles were loaded with an anticancer drug from prodigiosin (PG), which was obtained from bacteria, Serratia marcescens subsp. Marcescens. The release of paclitaxel (PT) was also tested as a control. The PG and PT were encapsulated using a single-emulsion solvent evaporation technique with PLGA as a polymer matrix and poly-(vinyl alcohol) (PVA) as an emulsifier. The dependence of particle size and morphology on processing conditions was also evaluated. In vitro release studies were used to elucidate drug loading efficiency, encapsulation efficiency and microparticle morphology using a combination of UV-visible (UV-Vis) spectrophotometry, optical Microscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and atomic force microscopy (AFM). The implications of the results are then explored using MDA-MB-231 cells (breast cancer cells) for the development of injectable, multi-functional, polymeric micro- and nano-particles for the controlled release of cancer drugs and the localized treatment of cancer