Publications by authors named "Masa A"

This study examined the feasibility of using natural rubber (NR) latex foam as a dye adsorbent and antibacterial foam. The dyes used in this experiment were Methylene Blue (MB) and Alizarin Yellow (AY). Foams with that optimum density were further evaluated for adsorption isotherm, kinetics, and thermodynamic data.

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Fillers have been widely used in natural rubber (NR) products. They are introduced to serve as a strategy for modifying the final properties of NR vulcanizates. Silica and calcium carbonate (CaCO) are among the fillers of choice when the color of the products is concerned.

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Nanocomposite foams of natural rubber (NR) with 5 phr of two kinds of nanofillers, nanoclay (NC) and cellulose nanofiber (CNF), were produced using the latex mixing method and foaming with azodicarbonamide. The effect of the nanofiller on the structure and mechanical properties of NR foams was investigated through SEM, TEM, tensile tests, WAXD, and compression set measurements. Smaller cells with a narrower distribution were attained in the NC/NR foam when compared to the NR and CNF/NR foams, and the expansion ratio was larger due to the suppression of the shrinkage in the NC/NR foam.

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We investigated the reinforcement behavior of small amounts of chemically unmodified cellulose nanofiber (CNF) in eco-friendly natural rubber (NR) nanocomposites. For this purpose, NR nanocomposites filled with 1, 3, and 5 parts per hundred rubber (phr) of cellulose nanofiber (CNF) were prepared by a latex mixing method. By using TEM, a tensile test, DMA, WAXD, a bound rubber test, and gel content measurements, the effect of CNF concentration on the structure-property relationship and reinforcing mechanism of the CNF/NR nanocomposite was revealed.

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As most plastic materials disintegrate without being properly reused after they are discarded, this present study developed a novel thermoplastic elastomer (TPE) using recycled high-density polyethylene (rHDPE) and natural rubber (NR) with kenaf fibre as a sustainable filler. Apart from being used as filler, this present study aimed to examine the use of kenaf fibre as a natural anti-degradant as well. The results indicated that the tensile strength of the samples was found to have significantly decreased after 6 months of natural weathering and had decreased by a further 30% after 12 months due to the chain scission of the polymeric backbones and the degradation of the kenaf fibre.

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Article Synopsis
  • * The study explored incorporating silver-doped zinc oxide (Ag-doped ZnO) into NR latex foam, successfully created through a microwave-assisted method and characterized to confirm the doping of silver particles onto ZnO.
  • * Results showed that adding Ag-doped ZnO enhanced the antibacterial properties of NR latex foam without altering its physical properties, achieving significant reductions in bacterial growth over 24 hours, especially at a 100 wt% AgNO content.
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Natural rubber (NR) is incompatible with hydrophilic additives like halloysite nanotubes (HNT) due to their different polarity. The silane coupling agent is the ideal component to include in such a compound to solve this problem. Many types of silane are available for polymer composites depending on their functionalities.

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A massive demand for rubber-based goods, particularly gloves, was sparked by the emergence of the COVID-19 epidemic worldwide. This resulted in thousands of tons of gloves being scrapped due to the constant demand for the items, endangering our environment in a grave way. In this work, we aimed to focus on the utilization of waste nitrile gloves (r-NBR) as a component blended with natural rubber (NR).

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Natural rubber (NR) nanocomposites reinforced with five parts per hundred rubber (phr) of two different nano-fillers, i.e., nanoclay (abbrev.

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Natural rubber latex (NRL) is a polymer (blend) extracted from the milky sap of para rubber trees. Due to being a natural biopolymer, NRL contains various proteins that may be allergenic to humans when in skin contact. Attempts have been made to use deproteinized natural rubber (DPNR) instead of impure NRL, and the final properties of these two types of rubber tend to differ.

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Halloysite Nanotubes (HNT) are chemically similar to clay, which makes them incompatible with non-polar rubbers such as natural rubber (NR). Modification of NR into a polar rubber is of interest. In this work, Epoxidized Natural Rubber (ENR) was prepared in order to obtain a composite that could assure filler-matrix compatibility.

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Informal carers provide an important role in supporting people with cancer. Aboriginal and Torres Strait Islander peoples experience higher cancer mortality than other Australians. To date, very little is known about the support needs of carers of Aboriginal and Torres Strait Islander adults with cancer.

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Carbonized natural filler can offer the production of low cost composites with an eco-friendliness value. The evolving field of electronics encourages the exploration of more functions and potential for carbonized natural filler, such as by modifying its surface chemistry. In this work, we have performed surface modification on carbonized wood fiber (CWF) prior to it being used as filler in the ethylene vinyl acetate (EVA) composite system.

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The aroma and volatile composition of wines from five red cultivars from NW Spain (Brancellao, Mencía, Merenzao, Mouratón and Sousón) have been studied by gas chromatography-mass spectrometry (GC-MS) and sensory descriptive analysis (SDA) during three consecutive vintages (2007-2009) in order to characterize these wines. In addition, relationships between the instrumental (volatile) and sensory variables were analyzed through the application of partial least squares regression (PLSR). Results revealed that the effect of "cultivar" was very important as a third of compounds (16 in total) varied significantly (P≤0.

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The volatile composition of white Agudelo, Blancolexitimo, Godello and red Serradelo cultivars (NW Spain) harvested at two different stages of ripening have been evaluated. C(6)-compounds, alcohols, volatile fatty acids, monoterpenes, C(13)-norisoprenoids, volatile phenols and carbonyl compounds were identified and quantified in free and glycosidically bound forms by gas chromatography-mass spectrometry (GC-MS). The total volatile concentration showed a significant increase between the two ripening stages studied for all cultivars.

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Cell wall-bound hydroxycinnamic acids and the composition of lignin were studied in relation to the digestibility of a collection of 91 maize silages in wethers. Total lignin and guaiacyl content showed the highest correlation coefficients with digestibility. Using the above-mentioned chemical parameters, eight equations were also developed to predict digestibility.

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Background: The effectiveness of the analysis of cell wall-bound hydroxycinnamic acids and the composition of lignin to evaluate the in vivo digestibility of a silage collection with unknown botanical composition was evaluated.

Results: Syringyl units content and total etherified phenols showed the highest correlation coefficients with in vivo dry matter digestibility (IVDMD) (r = - 0.792 and r = - 0.

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Objective: Considering that celiac disease (CD) is an autoimmune-based entity and the hepatitis C virus is suspected of being able to trigging autoimmune reactions, it has been hypothesized that hepatitis C virus infection might predispose to CD. The aim of this study was to investigate CD-related antibodies in a large series of hepatitis C virus-infected subjects that were also tested for non-organ-specific autoantibodies (NOSA) as indirect marker of autoimmune disorders.

Methods: Two hundred and forty-four patients with chronic hepatitis C virus infection (HCV-patients) and 121 patients with HCV-negative liver disease (non-HCV-patients) underwent NOSA determination and celiac serology (firstly, anti-tissue transglutaminase antibodies, then the cases which tested positive were subsequently evaluated for the presence of antiendomysial antibodies).

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In order to develop a method that allows to distinguish between white grape cultivars, the flavonoid profiles of 10 white accessions from the "Misión Biológica de Galicia" germplasm collection were studied during years 2003, 2004 and 2005 by high-performance liquid chromatography (HPLC). Twenty-four flavonoids (15 flavonols and 9 dihydroflavonols) were totally or partly identified, and significant differences between the studied flavonoid markers were found. With this method all the cultivars examined could be easily distinguished from each other, and we may conclude that this has been proved to be of great value for white grape cultivar recognition.

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We have previously shown that, assuming urea distribution volume (V) remains constant for 1 month, ionic dialysance (ID) allows the dialysis dose to be calculated without the need for blood sampling. The aim of this multicenter study was to verify whether the assumption of a constant V can be extended to 1 year. In clinically stable patients receiving thrice-weekly hemodialysis at 13 dialysis centers, V and Kt/V were assessed during three dialysis sessions at baseline and 1 year later using ID as dialyzer urea clearance and the single-pool urea kinetic model.

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In order to develop a method that allows to distinguish between grape cultivars, the anthocyanin profiles of 50 accessions from the "Misión Biológica de Galicia" germplasm collection were studied by high performance liquid chromatography (HPLC). Nineteen anthocyanins were totally or partly identified and significant quantitative differences between the studied anthocyanin markers were found. With this method all 50 cultivars examinated could be easily distinguished from each other.

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In June 2001, dengue transmission was detected in Havana, Cuba; 12,889 cases were reported. Dengue 3, the etiologic agent of the epidemic, caused the dengue hemorrhagic fever only in adults, with 78 cases and 3 deaths. After intensive vector control efforts, no new cases have been detected.

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Background: In vivo, the control of calcium-mediated acute PTH release during induced hypo- or hypercalcaemia is linked not only to plasma calcium concentration per se but also to the rate and direction of calcium change. In fact, during induced hypocalcaemia, the predominant mechanism that causes PTH to be released is the reduction of plasma Ca(2+) irrespective of the absolute starting concentration of ionized calcium. This mechanism, which is rate-dependent and even activated in conditions of hypercalcaemia, may be involved in the association, reported in several papers, between the basal Ca(2+) and the set point of the calcium-PTH curve.

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The calcium-PTH relationship in uremic patients has been often studied during dialysis sessions with high or low dialysate calcium concentration (CaD). This method has been used because it is less complex and invasive than i.v.

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Background: Despite progress and improvement in the dialysis modalities, cardiovascular disease remains the leading cause of death in patients receiving chronic hemodialysis therapy.

Methods: To determine the prevalence of myocardial abnormalities among these patients, thirty-nine patients (22 males and 17 females, ranging in age from 20 to 87; mean age 61.38 +/- 15.

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