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In the biomedical field, titanium alloys have long been preferred for orthopedic and dental devices due to their excellent biocompatibility and mechanical strength, making them suitable for long-term implantation. However, recent findings indicate that certain alloying elements, such as vanadium, cobalt, and copper, may pose cytotoxic risks when present at higher concentrations or under specific conditions. As a response to these concerns, current research is focused on developing titanium alloys that feature a lower elastic modulus and improved compatibility with bone elasticity. It also aims to exclude potentially cytotoxic elements and incorporate advanced surface modifications, thereby providing effective solutions to these challenges. Based on these identified needs this review highlights the latest advancements in the design of β-Ti alloys through safer and greener methods. It places particular emphasis on pre-clinical in vitro and in vivo studies that evaluate the safety and performance of implants. Additionally, discusses the potential of artificial intelligence and computational methods for predicting and optimizing alloy properties. Unlike previous reviews that focus mainly on microstructure, mechanical behavior or specific clinical niches, this review includes alloy design and processing with pre-clinical evidence, regulatory and intellectual-property dimensions, and life-cycle and sustainability assessments. By linking β-Ti alloy development to circular-economy strategies, biodegradable metallic alternatives and emerging machine-learning tools for alloy prediction, the review provides a framework for the clinical translation of safer and greener titanium implants, offering a complete overview of the critical factors influencing the future development of titanium alloy implants for biomedical applications.
The arrival of humans to the Americas at the end of the Pleistocene has been one of the foundations of the hypothesis that hunter-gatherer groups had a direct role in the extinction of megafauna. However, empirical evidence of the exploitation of megafauna by humans and associated chronological context are still scarce, especially in South America. Using evidence of modifications on osteological remains and the association of some lithic artifact we provide a reassessment of the megafauna that was exploited at the classic Taima-Taima site (Venezuela), with an updated chronology and paleoenvironmental inferences. Our preliminary results show that, at least, five species of extinct megaherbivores were probably exploited at the site, expanding the previous records, restricted to the proboscidean Notiomastodon platensis and the giant armadillo Glyptotherium cf. G. cylindricum. The new data of the other likely exploited taxa include the terrestrial sloth Glossotherium, the macrauchenid cf. Xenorhinotherium bahiense and a toxodontid. Both killing and slaughtering activities were likely practised. Seven new enamel radiocarbon dates show an age of 17.48–15.6 cal kyr BP for the fossiliferous strata, although this is likely to be a minimum age given the material's propensity for modern carbon uptake. The study of phytoliths and starch grains from the dental calculus of N. platensis identified five plant taxa from the phytoliths: arboreal dicotyledons, Poaceae, Marantaceae, Asteraceae and Arecaceae. Herbivore dental ecometrics and dietary inferences suggest that humans apparently exploited a diversity of grazing and browsing megaherbivores within heterogeneous landscapes of northern South America.
Helicobacter species are increasingly recognized in environmental reservoirs, yet their prevalence and diversity in tropical wetland ecosystems remain poorly understood. This study aimed to assess the prevalence, distribution, and diversity of Helicobacter spp. in a tropical wetland ecosystem, specifically within the Cuare Wildlife Refuge, Venezuela, focusing on waterbirds and associated aquatic matrices. We collected samples from avian faeces, water, plankton, oysters, soils, and microbial mats during two periods (October/2011 and March/2012). Analysis involved culture in HP selective medium, genus-specific PCR, 16S rRNA gene sequencing, phylogeny and water quality assessment. Helicobacter DNA was detected in 57% of samples (n = 148), with varying prevalence: water (94%), plankton (100%), oysters and soils (80%), microbial mats (50%), and avian faeces (42%). Prevalence in bird faeces was higher in resident (69%) than migratory (41%) species and showed a positive correlation with water salinity in October 2011 (r = 0.94, p < 0.05). Despite urease activity, all culture attempts on selective medium failed. Phylogenetic analysis revealed sequences clustering within H. pylori, H. pametensis, H. kayseriensis, H. brantae, and H. pullorum-related clades, alongside potentially novel lineages, highlighting significant diversity and zoonotic potential. Elevated enterococci levels (> 35 MPN/100 mL), exceeding guideline values, suggest sewage inputs and threats to this wildlife habitat. These findings identify waterbirds as carriers and wetlands as reservoirs for diverse commensal, pathogenic and zoonotic Helicobacter species in a relevant marine protected area of the Caribbean Sea.
In vitro cultivation of Theobroma cacao L. poses critical challenges, primarily due to the recalcitrant nature of its seeds and the high susceptibility of its tissues to phenolic oxidation. This research evaluated the effect of bioactive modulating agents (cysteine, ascorbic acid, and activated charcoal) and genotypic factors on in vitro germination. By employing an optimized surface disinfection methodology, 100 % asepsis was achieved, significantly surpassing historical records of contamination-related losses (up to 63 %). Germination efficiency reached 86.25 %, being significantly influenced by the Genotype × Environment interaction, where the 'Ocumare 61' cultivar demonstrated superior morphogenic competence. Statistical analysis validated robust mathematical models (R 2 adj of 73.77 % for germination and 81.05 % for oxidation), confirming that supplementation with activated charcoal effectively neutralized the cytotoxic quinone cascade through physical adsorption—a primary limiting factor in the 'Ocumare 60' cultivar. Response surface analysis identified the optimal performance in the M3 treatment with 'Ocumare 61'. We conclude that asepsis control and the stability of the redox microenvironment are decisive conditions for unlocking the germinative potential of cacao seeds. These findings establish a predictive framework that strengthens protocols for mass micropropagation and the conservation of elite germplasm.
Abstract The study of historical documents from the original excavation led by J. M. Cruxent, of museum collections, as well as results of fieldwork, are combined to provide a revised assessment of the archeologically site of Cucuruchú, which together with those of Taima-Taima and Muaco, document megafaunal lithic remains associated from the Late Pleistocene in northern Venezuela. Six vertebrate taxa are reported for Cucuruchú: five megaherbivores (a giant sloth, Eremotherium laurillardi .; a glyptodontid, Glyptotherium cf. G . cylindricum ; a macrauchenid, cf. Xenorhinotherium bahiense ; a proboscidean, Notiomastodon platensis ; and an equid, Equus sp.), and a turtle ( Kinosternon sp.). Two fragments of El Jobo projectiles were found in situ lying among megaherbivores bones, while another unidentified projectile fragment was also found in the same layer. Although no direct evidence of human exploitation on these megaherbivores remains has been found, the presence of El Jobo projectiles in the undisturbed fossil-bearing layer some of which are associated with fossil remains, could be a suggestive of such interaction. Two new radiocarbon dates indicate ages of at least ca. 15.3-16.0 kyr cal BP for the fossil-bearing layer, contrasting with the mid to late Holocene age originally reported. Cucuruchú is a window to the past and supports the presence of hunter-gatherers of the El Jobo culture in the region at the end of the Pleistocene.
