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Traditional fermented products can be adopted as probiotic carriers. This study was aimed at evaluating the potential of using Obushera, a traditional sorghum beverage from Uganda, as a carrier for Lactobacillus rhamnosus yoba.

Probiotic Obushera was produced by fermenting sorghum malt with Lb. rhamnosus yoba 2012 and Streptococcus thermophilus C106 at 30 °C and at room temperature (21°C-25 °C) for 24 h. Acidity, pH, total soluble solids and microbial counts were monitored. Consumer acceptability and purchase index of probiotic Obushera were compared to four commercial non-probiotic brands. Shelf stability of probiotic Obushera was determined by monitoring changes in pH, acidity, soluble solids, microbial counts and consumer acceptability during refrigerated storage.

Lactobacillus rhamnosus yoba 2012 multiplied and lowered the pH of Obushera from 5.3 to < 4.0 (p < 0.0001) whilst increasing acidity from 0.21 to 0.46 per cent (p < 0.0001) in 9 h at 30 °C. Consumer acceptability varied with Obushera brand (p < 0.0001). The overall acceptability score of probiotic Obushera (score of 6.4 = like slightly) was similar to that of the two most acceptable commercial brands (scores of 5.8 and 6.6). Acidity, pH and Lb. rhamnosus counts of probiotic Obushera varied within 0.6 per cent –1.05 per cent (p < 0.0001), 3.3–3.4 (p < 0.0001), and 8.2-9.2 log cfu/ml (p < 0.0001), respectively during two months of storage. The overall acceptability of probiotic Obushera (scores of 6.9-7.8) did not change significantly during storage (p = 0.185).

Traditional fermented foods such as Obushera can be adopted as carriers of probiotic microorganisms.

Use of commercial probiotic strains in traditional fermented foods is a novel approach that can be adopted to improve safety of traditional fermentations and health of consumers.

This paper aims to determine the potential for the spread of bacteria from raw meat and poultry during home food preparation to the surrounding kitchen environment, hands and prepared food due to unsafe handling practices, which are predicted by consumers' knowledge, behaviour and attitudes.

The potential for transfer of E.coli and C. jejuni was monitored in a simulated domestic kitchen environment while food preparation was filmed (n=60 respondents). A survey was also administered.

The results of the study show that transfer of bacteria around the kitchen environment and onto prepared meals are predicted by a lack of thoroughly washing contaminated hands, knives and chopping boards both during and after meal preparation. A higher level of perceived importance of correct food handling behaviour is associated with higher levels of educational attainment and age and food risk perceptions are positively associated with age.

The results highlight the importance of promoting preventative measures and the means of employing them specifically to the young and less educated public who do not frequently cook and prepare food.

This paper is the first to include a verifiable audit of consumer food safety behaviour, microbiological sampling of surfaces, food and hands as well as a consumer survey of knowledge, behaviour and attitudes.

The purpose of this paper was to gain a better understanding of wear behaviour of polymethylmethacrylate (PMMA) in contact with 316L stainless steel under different conditions (dry condition, distilled water and Ringer's solution). PMMA is commonly used in low-stress sliding application against metal. The effects of applied load and frequency on the wear rate of PMMA against 316L stainless steel were examined.

Tests were conducted under dry condition, in distilled water and in Ringer’s solution by using reciprocating wear machine. Worn surface morphology and composition was evaluated by scanning electron microscopy.

PMMA wear rate increases with the increase in applied load, naturally. An increase in sliding frequency increases the wear rate under dry condition, but it decreases the wear rate in water and in Ringer’s solution.

The objective of the present work was to gain a better understanding of the wear behaviour of PMMA in contact with 316L stainless steel under different conditions (dry condition, distilled water and Ringer's solution). The effects of applied normal load and frequency on the wear rate of PMMA against 316L stainless steel at various conditions were examined experimentally. This information may have future implications for the design of materials which have a contact with physiological fluid in orthopeadic implants.

This paper aims to analyze the corrosion behavior in Ringer solution of six commercially used Ni-based alloys that are present and commonly used as metallic biomaterials.

The specimens were received in the form of cylindrical ingots and were cut to get five samples of each brand with a cylindrical shape of 2 mm height to conduct the study. In this scientific research, the following techniques were used: open circuit potential, potentiodynamic polarization studies, and electrochemical impedance spectroscopy.

The study findings revealed the passivation tendency of the different specimens. Additionally, when the materials were compared, it was discovered that the decisive factor for high corrosion resistance was the chromium concentration. However, with similar chromium content, the stronger concentration in molybdenum increased the resistance. According to the results obtained in this investigation, the biological safety of the dental materials studied in Ringer solution was considered very high for specimens 1 and 2, and adequate for the other samples.

Metal alloys used as biomaterials in contact with the human body should be deeply investigated to make sure they are biocompatible and do not cause any harm. The corrosion resistance of an alloy is the most important characteristic for its biological safety, as all problems arise because of the corrosion process. There is scarce investigation in these Ni-based dental biomaterials, and none found in these commercially used dental materials in Ringer solution.

SS316L alloy used in biomedical application and the alloy have Fe, Cr and Ni elements and release this ion into the human body causing dangerous effects for the human body, and make the SS316L, which is used as surgical implant failure in short time in biomedical application. This study aims to use Ti6Al4V as coating for SS316L alloy to make it have bio inert surface, and modified the surface alloy for biomedical application from another part in this study, we want to decrease the corrosion rate for SS316L in simulated body surface Ringer solution.

The morphology, roughness, XRD of the coating, potential polarization and electrochemical impedance spectra investigation to study the effect of Ti6Al4V coating on corrosion behaviors of SS316L in the Ringer solution.

This study discusses the modification of SS316L surfaces by using Ti6Al4V radio magnetron frequency sputtering techniques, the results of the EIS and polarization of SS316L in Ringer’s solution at 37°C shows that improved resistance against corrosive ions for all the samples coating with Ti6Al4V and especially with a coating have a thickness of 850 nm at a sputtering power of 150 W.

Polarization and electro chemical impedance spectra were assessed to investigate the effect of Ti6Al4V coating on corrosion behaviors of SS316L alloy in the Ringer solution.

This study discussed the modification SS316L surfaces by using Ti6Al4V radio magnetron frequency sputtering techniques. The results of the EIS and polarization of SS316L in Ringer’s solution at 37°C improved resistance against corrosive ions for all the samples coating with a Ti6Al4V and specificity with the coating sample have a thickness 850 nm at a sputtering power of 150 W.

The goal of this study to modification SS316L alloy surface by using Ti6al4V RF Sputtering to give the SS316L alloy more resistance for biocorrosion.

In this research, Ti6Al4V RF sputtering as a coating for SS316L, study the bio corrosion behaviors in Simulated body fluid Ringer solution and investigation the corrosion by using EIS analysis.

The biomaterials are natural or synthetic materials used to improve quality of life either by replacing tissue/organ or assisting their function in medical field. The purpose of the study is to analyze the hydroxyapatite (HAP), HAP-TiO₂ (25 percent) composite coatings deposited on 316 LSS by High Velocity Flame Spray (HVFS) technique.

The coatings exhibit almost uniform and dense microstructure with porosity (HAP = 0.153 and HAP-TiO₂ composite = 0.138). Electrochemical corrosion testing was done on the uncoated and coated specimens in Ringer solution (SBF). As-sprayed coatings were characterized by XRD, SEM/EDS and cross-sectional X-ray mapping techniques before and after dipping in Ringer solution. Microhardness of composite coating (568.8 MPa) was found to be higher than HAP coating (353 MPa).

During investigations, it was observed that the corrosion resistance of steel was found to have increased after the deposition of HAP and HAP-TiO₂ composite coatings. Thus, coatings serve as an effective diffusion barrier to prohibit the diffusion of ions from the SBF into the substrate. Composite coatings have been found to be more corrosion resistant as compared to HAP coating in the simulated body fluid.

It has been concluded that corrosion resistance of HAP as well as composite coating is because of the desirable microstructural changes such as low porosity high microhardness and flat splat structures in coatings as compared to bare specimen.

This study is useful in the selection of biomedical implants.

This study is useful in the field of biomaterials.

No reported literature on corrosion behavior of HAP+ 25%- TiO₂ has been noted till now using flame spray technique. The main focus of the study is to investigate the HAP as well as composite coatings for biomedical applications.

The aim of this paper is to obtain optimal corrosion resistance of certain differently treated samples by investigation of their electrochemical properties.

Nanocrystalline plasma electrolytic carbonitriding (PEC/N) treatments were applied on the surface of commercially pure titanium in a glycerol bath with different additives. The carbonitriding process was performed in a glycerol bath with different additives such as carbamide, natrium nitrate and triethanolamine. The effects of electrolyte composition on chemical composition and corrosion resistance of the PEC/N films were examined by means of X‐ray diffraction, scanning electron microscopy, potentiodynamic polarization and electrochemical impedance spectroscopy in a Ringer solution.

The results showed that the PEC/N films obtained in solutions with triethanolamine (T‐film) had better corrosion resistance. All coated samples had a better electrochemical behaviour compared with the untreated substrate. Different nano‐structures and morphologies were obtained by different additives in electrolyte.

The results obtained in this research into nanocrystalline PEC/N can be used wherever good corrosion and wear resistance with the highest efficiency is required.

The speed of treatment by this technique makes this method very suitable for the industrial surface treatment of different components.

Corrosion resistance measurements were performed on AISI 316L stainless steel biomaterial samples after three types of treatments: abrasive finishing (MP), standard electropolishing (EP), and magnetoelectropolishing (MEP). The corrosion studies were carried out in Ringer's solution at a room temperature. Potentiodynamic plots obtained were the basis for the analysis of measurement accuracy and uncertainty with the statistical tests results done in Statistica 64/10 software. The results of corrosion studies indicate a significant difference in the breaking potential (Epit) values, dependent on surface treatment. The highest mean values have been obtained on samples after MEP (Epit=961 mV), much lower – after a standard electropolishing EP (Epit=525 mV), and the lowest – after the abrasive treatment MP (Epit=222 mV), all of them measured against a saturated calomel electrode SCE potential. The corrosion results obtained are well correlated with the nanoindentation measurement results (Young's modulus and nanohardness). The paper aims to discuss these issues.

The AISI 316L austenitic stainless steel samples served for the study. There were 11 (MP) and 14 (EP) samples used for each of the treatment, and 31 samples used for magnetoelectropolishing MEP. All polarization measurements were made after one hour immersion in the Ringer's solution. Statistical tests were used to treat the results obtained.

After magnetoelectropolishing MEP130, the pitting corrosion resistance is much better than that after abrasive polishing MP and/or a standard electropolishing EP130. It was proved on a big statistical sample that the pitting corrosion potential Epit after MEP130 is over 1.8 times higher than that after EP130 and over 4.3 times higher than that after MP. The results obtained are in good agreement with the nanoindentation measurement results.

This is an original study of the corrosion resistance of AISI 316L SS in Ringer's solution. The breaking potential Eb obtained is comparable with that of NiTi alloys, not reported anywhere before. The results have been well confirmed statistically (on 31 samples after MEP).

The purpose of this paper is to investigate the effect of thermal treatment at low partial pressure of oxygen on electrochemical corrosion resistance of Ti‐47Al‐2Cr (at %) intermetallic, known as γ‐TiAl alloy.

The surfaces of the samples were modified by thermal treatment at different temperatures in N₂ gas flow for an hour. Characterization of the modified surface layers was carried out by microscopic examinations, hardness and roughness tests, and X‐ray diffraction analyses. Potentiodynamic polarization was used to evaluate the corrosion performance of γ‐TiAl in Ringer's solution.

The results indicated that the alloy treated at 950 °C had the optimum corrosion resistance, which can be attributed to the formation of an oxide layer by the surface thermal treatment and increase of the passive layer thickness.

Low corrosion rate (CR), high pitting potential (Epit), and more noble corrosion potential (Ecorr) make it possible for γ‐TiAl to be considered as a candidate for biomedical applications.

The treatment described in the paper is a novel method for surface modification of this type of alloy and results showed that it was an effective treatment and that the corrosion resistance improved remarkably.

This paper aims to study the deposition of ZrO₂ on 316L stainless steel surface using cathodic plasma electrolytic deposition (CPED) technique in potassium hexafluorozirconate (K₂ZrF₆) electrolyte solution to promote its corrosion and tribological properties.

Plasma electrolytic oxidizing (PEO) technique is commonly used to form zirconium dioxide (ZrO₂) on various substrates. But, in this paper, cathodic type of this technique (CPED) was used.

Composition of the surface layer was analyzed by X-ray diffraction (XRD) and the formation of ZrO₂ on the substrate was confirmed. Scanning electron microscope (SEM) was used to observe the unique morphology of the surface layer. The corrosion resistance of the coated surface was investigated by electrochemical methods involving cyclic voltammetery in Ringer’s solution. The treated sample showed a better pitting resistance. Pin-on-disk wear tests revealed that the friction coefficient of the coated sample is lower than that of the substrate. Also, it was shown that hardness and roughness of the coated sample increased after plasma electrolytic treatment.

This paper considers the CPED of ZrO₂ coating on 316L stainless steel. Some recent research works with ZrO₂ coating have been prepared by PEO. There is limited or no record on the study of ZrO₂ coatings by CPED process. In this study, the effort has been made to prepare a zirconia (ZrO₂) coating on the stainless steel substrate through cathodic plasma electrolytic process under 200 V. Due to the excellent wear resistance, ZrO₂ may be used as a high resistant and protective coating on stainless steels, which are widely used in industries and biomedical applications.