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1.
Sensors (Basel) ; 22(23)2022 Nov 23.
Article in English | MEDLINE | ID: mdl-36501789

ABSTRACT

Improper cycling posture is linked to a variety of spinal musculoskeletal diseases, including structural malformation of the spine and back discomfort. This paper presents a novel smart shirt integrated tri-axial gyroscope and accelerometer that can detect postural variation in terms of spinal curvature changes. To provide accurate feedback to the wearer and improve the wearer's correct movement, the garment is able to recognize trunk body posture. The gyroscope/accelerometer was placed around the upper and mid trunk of the user to record tri-axial angular velocity data. The device can also be used to help determine the trunk bending angle and monitor body postures in order to improve optimal orientation and position. The garment enables continuous measurement in the field at high sample rates (50 Hz), and the sensor has a large measurement range (16 g, 2000°/s). As electronic components are non-washable, instead of encapsulating them, a detachable module was created. In this, magnets are embedded in the jersey, and allow the positioning and removal of the sensor. The test results show that the average trunk-bending angle was 21.5°, and 99 percent of the observed angle fell within the standard (ranging from 8° to 35°). The findings demonstrate the feasibility of employing the smart shirt sensor to estimate trunk motions in the field on a regular basis.


Subject(s)
Movement , Posture , Motion , Spine , Feedback
2.
Heliyon ; 8(8): e09856, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35965977

ABSTRACT

In this experimental study, untreated Ethiopian high land bamboo fibres were characterized and detected the optimal properties. In the investigation, SEM was applied to examine the surface texture of the fibres. The chemical bonds of the molecules (functional groups) were identified by Fourier transform infrared spectra (FTIR). The thermal properties of the fibre were explored with a thermogravimetric analyser, and the results were confirmed by differential thermo-gravimetric analysis (DTG). Mechanical properties were improved using the experimental design principle. The design is based on the RSM methodology three-factor three-level to present mathematical models. At various plant ages, the culm wall thickness in the radial direction and soaking duration of the single fibre is extracted using a roller crusher machine. The operating parameters and optimal mechanical properties were validated using confirmation tests. Breaking force 796.5cN, tenacity 46.8cNtex-1, work done 456cNmm, and modulus 1814cNtex-1 were the optimal mechanical characteristics achieved at the operating parameters 2.0 years age, a calm thickness layer coded values of 0.6 along the radial direction, and 3.8 days soaking time when compared to mechanical properties 1-3 years plant age, calm thickness layers of from primary (-1) to secondary layers (1) along with the radial direction, and 3-9 days soaking time.

3.
Front Pediatr ; 10: 966237, 2022.
Article in English | MEDLINE | ID: mdl-36034565

ABSTRACT

Background: Children are more vulnerable to developing active Mycobacterium tuberculosis infection which causes significant morbidity and mortality. However, the contribution of childhood tuberculosis and its treatment outcomes have not been well documented, and no research has been conducted in eastern Ethiopia. Objective: This study aimed to assess the treatment outcome and its predictors of pediatric tuberculosis in eastern Ethiopia from September 1, 2017 to January 30, 2018. Methods: A retrospective study was conducted in eight selected hospitals in eastern Ethiopia. Data on 2002 children with tuberculosis was extracted by using the standard checklist of the national tuberculosis treatment format. Treatment outcomes were determined according to the standard definitions of the National Tuberculosis and Leprosy Control Programme. Data were entered into Epi Data software version 3.1 and exported to Statistical Package for Social Science (SPSS) version 20 for analysis. Bivariable and multivariable regression analyses were carried out to examine the associations between dependent and independent variables. A P-value of <0.05 was considered statistically significant. Result: The overall successful treatment rate was 1,774 (88.6%) [95% confidence interval (CI): (80.59-97.40)]. A total of 125 (6.2%), 1,648 (82.3%), 59 (2.9%), and 19 (0.9%) children with tuberculosis (TB) were cured, completed, defaulted, and died, respectively. A high number of defaulters and deaths were reported in the age group <10 years. More children with smear-positive pulmonary TB (74.4%) were cured, while smear-negative tuberculosis had higher treatment completion rates. Being male in sex (adjusted odds ratio (AOR): 0.71, 95% CI: 0.53, 0.96) and those with human immunodeficiency virus (HIV) positive sero status (AOR: 0.51, 95% CI: 0.29, 0.90) had a lower chance of a successful treatment outcome. Conclusion: In this study, thee treatment success rate was higher than the recent World Health Organization report. Those males and HIV seropositive status were less likely to have a successful treatment outcome. Therefore, efforts should be made by each health institution in eastern Ethiopia by giving emphasis on male and HIV-positive individuals.

4.
Gels ; 7(4)2021 Nov 27.
Article in English | MEDLINE | ID: mdl-34940296

ABSTRACT

Cellulose-based hydrogels were prepared by the extraction of cellulose from corncobs after the removal of lignin and hemicellulose with the use of alkali-acid treatment. Acrylate-based hydrogels presently available for personal hygiene uses are not biodegradable. In this study, a biodegradable cellulose-co-AMPS personal hygiene hydrogel was synthesized. The hydrogel was synthesized by graft co-polymerization of 2-acrylamido2-methyl propane sulfonic acid onto corncob cellulose by using potassium persulfate (KPS) as an initiator and borax decahydrate (Na2B4O7·10H2O) as a cross-linking agent. Structural and functional characteristics of the hydrogel such as swelling measurements, antimicrobial tests, FTIR spectra and thermogravimetric analysis were done. The hydrogel showed an average swelling ratio of 279.6 g/g to water and 83.3 g/g to a urine solution with a 97% gel fraction. The hydrogel displayed no clear inhibition zone and did not support the growth of bacteria, Gram-positive or -negative. The FT-IR spectra of the hydrogel confirmed the grafting of an AMPS co-polymer onto cellulose chains. The thermal properties of the hydrogel showed three-step degradation, with a complete degradation temperature of 575 °C.

5.
Materials (Basel) ; 14(16)2021 Aug 09.
Article in English | MEDLINE | ID: mdl-34442988

ABSTRACT

The aim of this study is to develop a mathematical model for the prediction of compression pressure based on fabric parameters, such as engineering stress, engineering strain and engineering modulus of elasticity. Four knitted compression fabrics with different fibrous compositions and knit structures were used. Rectangular-cut strips were employed for the force-elongation characterization of the fabrics. The experimental pressure values between the fabric and rigid cylinder were assessed using a Picopress pressure measuring device. The mechanical and physical parameters of the fabric that influence the interface pressure, such as strain, elasticity modulus/stress and thickness, were determined and integrated into Laplace's law. A good correlation was observed between the experimental and calculated pressure values for all combinations of fabrics, mounted with variable tension on the cylinder. Over the considered range of pressures, the difference between the two datasets was generally less than 0.5 mmHg. The effect of washing after five, ten and fifteen washing cycles on the fabric-cylinder interface pressure was found to be significant.

6.
Polymers (Basel) ; 13(7)2021 Apr 01.
Article in English | MEDLINE | ID: mdl-33915955

ABSTRACT

Increasing interest in bio-based polymers and fibers has led to the development of several alternatives to conventional plastics and fibers made of these materials. Biopolymer fibers can be made from renewable, environmentally friendly resources and can be fully biodegradable. Biogenic resources with a high content of carbohydrates such as starch-containing plants have huge potentials to substitute conventional synthetic plastics in a number of applications. Much literature is available on the production and modification of starch-based fibers and blends of starch with other polymers. Chemistry and structure-property relationships of starch show that it can be used as an attractive source of raw material which can be exploited for conversion into a number of high-value bio-based products. In this review, possible spinning techniques for the development of virgin starch or starch/polymer blend fibers and their products are discussed. Beneficiation of starch for the development of bio-based fibers can result in the sustainable replacement of oil-based high-value materials with cost-effective, environmentally friendly, and abundant products.

7.
Bioresour Bioprocess ; 8(1): 35, 2021 Apr 29.
Article in English | MEDLINE | ID: mdl-38650230

ABSTRACT

A wide variety of biomass is available all around the world. Most of the biomass exists as a by-product from manufacturing industries. Pulp and paper mills contribute to a higher amount of these biomasses mostly discarded in the landfills creating an environmental burden. Biomasses from other sources have been used to produce different kinds and grades of biomaterials such as those used in industrial and medical applications. The present review aims to investigate the availability of biomass from pulp and paper mills and show sustainable routes for the production of high value-added biomaterials. The study reveals that using conventional and integrated biorefinery technology the ample variety and quantity of waste generated from pulp and paper mills can be converted into wealth. As per the findings of the current review, it is shown that high-performance carbon fiber and bioplastic can be manufactured from black liquor of pulping waste; the cellulosic waste from sawdust and sludge can be utilized for the synthesis of CNC and regenerated fibers such as viscose rayon and acetate; the mineral-based pulping wastes and fly ash can be used for manufacturing of different kinds of biocomposites. The different biomaterials obtained from the pulp and paper mill biomass can be used for versatile applications including conventional, high performance, and smart materials. Through customization and optimization of the conversion techniques and product manufacturing schemes, a variety of engineering materials can be obtained from pulp and paper mill wastes realizing the current global waste to wealth developmental approach.

8.
Materials (Basel) ; 13(18)2020 Sep 10.
Article in English | MEDLINE | ID: mdl-32927922

ABSTRACT

This research focused on the investigation of the thermophysiological comfort properties of four selected knitted fabrics of different fiber blend ratios suitable for cycling wear. Comfort-related properties of the fabrics were determined and compared including air permeability, moisture management properties, drying time, thermal conductivity, and water vapor permeability. For those comfort properties of the fabric to be correlated, fabric structural properties, fabric density, fabric weight, and fabric thickness have been considered. Suited fabrics should have good air permeability, thermal conductivity, moisture management properties, and a short drying time. According to the measurement results, the fabric polyamide/elasane (58/42 PA6.6/EL) with good air permeability, thermal conductivity, moisture management properties, and short drying time was more suited for summer cycling clothing. Furthermore, this paper provides a new understanding of considerations that are needed for several end uses involving specific activity levels.

9.
J Environ Manage ; 262: 110329, 2020 May 15.
Article in English | MEDLINE | ID: mdl-32250808

ABSTRACT

Extraction of keratin from keratinous waste materials, such as chicken feathers, has been identified as the favourable approach in beneficiation of this biomass. The chemical extractions of keratin by reducing agents are usually preferred because the process is much faster than its counterpart, oxidation extraction. One such reduction extraction is the use of a mixture of sodium bisulphite, sodium dodecyl sulphate and urea. There are at least five factors that may affect the keratin extraction process and its final properties when using this extraction. Even though this extraction method is often used, the effects of its independent variables have not been studied; as a result, the effects of independent variables cannot be fully linked to the extraction process and final keratin properties. Therefore, this study aimed to optimise the extraction of keratin from waste chicken feathers using sodium bisulphite, sodium dodecyl sulphate and urea. The optimisation was statistically performed using Response Surface Methodology (RSM) linked with Box-Behnken Design. After screening the independent variable using one factor at a time method, the concentration of sodium bisulphite, concentration of sodium dodecyl sulphate, reaction temperature and reaction time were chosen for the study. Twenty-nine experiments were statistically designed and executed, and their results were used to analyse the effects of all the independent variables in order to optimise the extraction process. The reaction temperature was found to be the most significant factor, while the concentration of sodium dodecyl sulphate was the most insignificant factor of this extraction process. Independent variables significance order was reaction temperature > reaction time > concentration of NaHSO3 > concentration of NaC12H25SO4. The designed reduced cubic model was significant and was used to predict the protein yield from the keratin extraction using sodium bisulphite.


Subject(s)
Feathers , Keratins , Animals , Chickens , Sodium Dodecyl Sulfate , Sulfites , Urea
10.
Sensors (Basel) ; 20(24)2020 Dec 20.
Article in English | MEDLINE | ID: mdl-33419258

ABSTRACT

Fabric stretch sensors are available as planar fabrics, but their reliability and reproducibility are low. To find a good working setup for use in an elastic sports garment, the design of such sensors must be optimized. The main purpose of this study was to develop resistive strain sensors from stretchable conductive fabric and investigating the influence of stretchability on conductivity/resistivity. The influence of using the sensor in a sweat rich environment was also determined, in order to evaluate the potential use of the sensor in sporting garments. The sensor resistivity performance was analyzed for its sensitivity, working range, and repeatability and it was determined what makes the sensitivity when elongated or stretched. The resistivity was found to decrease with elongation if no sweat is present, this can be due to molecular rearrangement and a higher degree of orientation that improves the conductivity of a material. The result from this finding also shows that for wearable applications the commercial EeonTexTM conductive stretchable fabric did not show a considerable resistivity increase, nor a good sensitivity. The sensitivity of the sensor was between 0.97 and 1.28 and varies with different elongation %. This may be due to the mechanical deformation characteristics of knitted samples that lead to changes in conductivity. We advise that the testing performed in this paper is done by default on new stretch sensitive textile materials, so practical use of the material can be correctly estimated.

11.
Waste Manag ; 72: 371-388, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29132781

ABSTRACT

Commercially processed, untreated chicken feathers are biologically hazardous due to the presence of blood-borne pathogens. Prior to valorisation, it is crucial that they are decontaminated to remove the microbial contamination. The present study focuses on evaluating the best technologies to decontaminate and pre-treat chicken feathers in order to make them suitable for valorisation. Waste chicken feathers were washed with three surfactants (sodium dodecyl sulphate) dimethyl dioctadecyl ammonium chloride, and polyoxyethylene (40) stearate) using statistically designed experiments. Process conditions were optimised using response surface methodology with a Box-Behnken experimental design. The data were compared with decontamination using an autoclave. Under optimised conditions, the microbial counts of the decontaminated and pre-treated chicken feathers were significantly reduced making them safe for handling and use for valorisation applications.


Subject(s)
Decontamination , Feathers , Animals , Chickens , Organic Chemicals , Refuse Disposal , Surface-Active Agents
12.
Waste Manag ; 68: 626-635, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28687152

ABSTRACT

The characterisation of the chemical properties of the whole chicken feather and its fractions (barb and rachis), was undertaken to identify opportunities for valorizing this waste product. The authors have described the physical, morphological, mechanical, electrical and thermal properties of the chicken feathers and related them to potential valorisation routes of the waste. However, identification of their chemical properties is necessary to complete a comprehensive description of chicken feather fractions. Hence, the chicken feathers were thoroughly characterised by proximate and ultimate analyses, elemental composition, spectroscopic analyses, durability in different solvents, burning test, and hydrophobicity. The proximate analysis of chicken feathers revealed the following compositions: crude lipid (0.83%), crude fibre (2.15%), crude protein (82.36%), ash (1.49%), NFE (1.02%) and moisture content (12.33%) whereas the ultimate analyses showed: carbon (64.47%), nitrogen (10.41%), oxygen (22.34%), and sulphur (2.64%). FTIR analysis revealed that the chicken feather fractions contain amide and carboxylic groups indicative of proteinious functional groups; XRD showed a crystallinity index of 22. Durability and burning tests confirmed that feathers behaved similarly to animal fibre. This reveals that chicken feather can be a valuable raw material in textile, plastic, cosmetics, pharmaceuticals, biomedical and bioenergy industries.


Subject(s)
Feathers/chemistry , Waste Products , Animals , Chickens , Conservation of Energy Resources , Conservation of Natural Resources , Nitrogen , Proteins
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