Anodically polarized nickel electrodes in DMSO or DMF solutions of pseudohalide ions: IR spectroelectrochemical studies

A novel subtractively normalized interfacial Fourier transform infrared spectroscopic (SNIFTIRS) investigation of anodically polarized nickel electrodes in pseudohalide-containing DMF or DMSO solutions (i.e. OCN⁻, SCN⁻, SeCN⁻), in supporting electrolyte, tetrabutylammonium perchlorate (TBAP), is presented. In general, the data showed that nickel demonstrated irreversible anodic dissolution in all solutions studied at very high values of the applied potential, > +500 mV (AgCl/Ag). The predominant speciation of nickel in these systems was as complex ions consisting of Ni²⁺ ion complexed to pseudohalide ions and solvent molecules. Insoluble films and dissolved CO₂ were also detected, though mostly in the Ni/OCN⁻ systems studied. Ni(II)/pseudohalide complex ion species detected were modeled using solutions containing Ni²⁺ ion mixed with pseudohalide ion in different mole ratios. In general, the Ni/OCN⁻ electrochemical system behaved differently relative to those of Ni/SCN⁻ and Ni/SeCN⁻ due to the difference in colors observed in cell solutions after SNIFTIRS experiments which was mirrored in the model solutions. Ni(II)-cyanate species had a different, coordination geometry and gave a characteristic bright blue color due possibly to Ni(NCO)₄²⁻ ion while Ni(II) thiocyanate and selenocyanate complex ion species had octahedral coordination geometries containing solvent and one coordinated pseudohalide ion and formed greeny yellow solutions

A Method for Avoiding the Xanthoproteic-associated Discolouration in Reprecipitated (Nitric-acid-digested) Hydroxyapatite Prepared from Mammalian Bone Tissue

A procedure for producing kilogram quantities of a biomedically suitable reprecipitated hydroxyapatite (HAp) powder, which is free of the xanthoproteic-associated discolouration caused by nitric acid interaction with the protein content in bones during digestion, has been developed. Essentially bones were defatted by boiling and then pyrolysed at 1000 °C to burn off the collagenous proteins and produce flakey bleached bones. This bone was then crushed and ground and digested in nitric acid solution to produce digest solutions free of the highly staining orange colouration normally associated with nitric acid digestions of bone material.. Finely divided, white solids could then be reprecipitated as usual from the digests by addition of NaOH solution under a nitrogen atmosphere with heating and stirring at 70 °C of the precipitate to enable its maturation into an HAp phase. The products derived from this procedure were characterised using spectroscopic, microscopic and particle sizing techniques. These analyses showed the resultant powders to be low crystallinity hydroxyapatite of consistent morphology and which possessed either acceptably low or below detection limit levels of heavy metals so rendering it as a potentially valuable source of powder for biomedical applications such as plasma spraying or for implant or prosthesis manufacture

The association between salt taste perception, mediterranean diet and metabolic syndrome: a cross-sectional study

Metabolic syndrome (MetS) is a widespread disorder and an important public health challenge. The purpose of this study was to identify the association between salt taste perception, Mediterranean diet and MetS. This cross-sectional study included 2798 subjects from the general population of Dalmatia, Croatia. MetS was determined using the Joint Interim Statement definition, and Mediterranean diet compliance was estimated using Mediterranean Diet Serving Score. Salt taste perception was assessed by threshold and suprathreshold testing (intensity and hedonic perception). Logistic regression was used in the analysis, adjusting for important confounding factors. As many as 44% of subjects had MetS, with elevated waist circumference as the most common component (77%). Higher salt taste sensitivity (lower threshold) was associated with several positive outcomes: lower odds of MetS (OR = 0.69; 95% CI 0.52-0.92), lower odds for elevated waist circumference (0.47; 0.27-0.82), elevated fasting glucose or diabetes (0.65; 0.45-0.94), and reduced HDL cholesterol (0.59; 0.42-0.84), compared to the higher threshold group. Subjects with lower salt taste threshold were more likely to consume more fruit, and less likely to adhere to olive oil and white meat guidelines, but without a difference in the overall Mediterranean diet compliance. Salt taste intensity perception was not associated with any of the investigated outcomes, while salty solution liking was associated with MetS (OR = 1.85, CI 95% 1.02-3.35). This study identified an association between salt taste perception and MetS and gave a new insight into taste perception, nutrition, and possible health outcomes

A review on the use of Hydroxyapatite-carbonaceous structure composites in bone replacement materials for strengthening purposes

Biomedical materials constitute a vast scientific research field, which is devoted to producing medical devices which aid in enhancing human life. In this field, there is an enormous demand for long-lasting implants and bone substitutes that avoid rejection issues whilst providing favourable bioactivity, osteoconductivity and robust mechanical properties. Hydroxyapatite (HAp)-based biomaterials possess a close chemical resemblance to the mineral phase of bone, which give rise to their excellent biocompatibility, so allowing for them to serve the purpose of a bone-substituting and osteoconductive scaffold. The biodegradability of HAp is low (Ksp ≈ 6.62 × 10⁻¹²⁶) as compared to other calcium phosphates materials, however they are known for their ability to develop bone-like apatite coatings on their surface for enhanced bone bonding. Despite its favourable bone regeneration properties, restrictions on the use of pure HAp ceramics in high load-bearing applications exist due to its inherently low mechanical properties (including low strength and fracture toughness, and poor wear resistance). Recent innovations in the field of bio-composites and nanoscience have reignited the investigation of utilising different carbonaceous materials for enhancing the mechanical properties of composites, including HAp-based bio-composites. Researchers have preferred carbonaceous materials with hydroxyapatite due to their inherent biocompatibility and good structural properties. It has been demonstrated that different structures of carbonaceous material can be used to improve the fracture toughness of HAp, as they can easily serve the purpose of being a second phase reinforcement, with the resulting composite still being a biocompatible material. Nanostructured carbonaceous structures, especially those in the form of fibres and sheets, were found to be very effective in increasing the fracture toughness values of HAp. Minor addition of CNTs (3 wt.%) has resulted in a more than 200% increase in fracture toughness of hydroxyapatite-nanorods/CNTs made using spark plasma sintering. This paper presents a current review of the research field of using different carbonaceous materials composited with hydroxyapatite with the intent being to produce high performance biomedically targeted materials

Guiding principles for identification, evaluation and conservation of Vitis vinifera L. subsp. sylvestris

Conservation of grapevine genetic resources is an important and long lasting task. Here, partners of the InWiGrape Activity of the European Cooperative Programme for Plant Genetic Resources have proposed a set of descriptors that will assist in identification, conservation and study of genetic resources of Vitis vinifera L. subsp. sylvestris. A distribution map of Vitis vinifera L. subsp. sylvestris populations in Europe was produced, with on-line access through the European Vitis Database. The several different aspects of conservation of Vitis vinifera L. subsp. sylvestris including bibliographical references, identification in the wild, in situ and ex situ conservation have been discussed. The descriptors and the map will assist different stakeholders, working on biodiversity and ecosystems in more effective conservation of wild grapevine genetic resources

Development and characterization of a xenograft material from New Zealand sourced bovine cancellous bone

A xenograft (bovine hydroxyapatite [BHA]) was developed from New Zealand sourced bovine cancellous bone by a successful defatting and deproteinizing procedure. The BHA was chemically, compositionally and structurally characterized. Fourier transform infrared spectroscopy confirmed the removal of organic matter from the bone matrix and the presence of carbonate (CO3 2-), hydroxyl (OH−), and phosphate (PO4 3-) functional groups. X-ray diffraction analysis suggested that the processed bone corresponds characteristically to hydroxyapatite (HA). SEM analysis showed that the BHA has an interconnected porous architecture with a pore diameter ranging from 100 to 700 μm while µCT analysis calculated the total porosity as 73.46% ± 1.08. Furthermore, the BHA was stable up to 1000°C and lost only 1.8% of its weight. The Ca/P molar ratio of the BHA was 1.58, which is comparable with commercially available natural HA-Endobon®. After 28 days of incubation in simulated body fluid (SBF), the pH value only fluctuated between 7.1 and 7.5 and the BHA scaffold did not degrade significantly by weight indicating the scaffold had excellent chemical and structural stability. In vitro studies showed the BHA was cytocompatible and supported the proliferative growth of Saos-2 osteoblast cells. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1054–1062, 2017. © 2016 Wiley Periodicals, Inc.info:eu-repo/semantics/publishe