Experimental investigation of orangutans’ lithic percussive and sharp stone tool behaviours

Early stone tools, and in particular sharp stone tools, arguably represent one of the most important technological milestones in human evolution. The production and use of sharp stone tools significantly widened the ecological niche of our ancestors, allowing them to exploit novel food resources. However, despite their importance, it is still unclear how these early lithic technologies emerged and which behaviours served as stepping-stones for the development of systematic lithic production in our lineage. One approach to answer this question is to collect comparative data on the stone tool making and using abilities of our closest living relatives, the great apes, to reconstruct the potential stone-related behaviours of early hominins. To this end, we tested both the individual and the social learning abilities of five orangutans to make and use stone tools. Although the orangutans did not make sharp stone tools initially, three individuals spontaneously engaged in lithic percussion, and sharp stone pieces were produced under later experimental conditions. Furthermore, when provided with a human-made sharp stone, one orangutan spontaneously used it as a cutting tool. Contrary to previous experiments, social demonstrations did not considerably improve the stone tool making and using abilities of orangutans. Our study is the first to systematically investigate the stone tool making and using abilities of untrained, unenculturated orangutans showing that two proposed pre-requisites for the emergence of early lithic technologies–lithic percussion and the recognition of sharp-edged stones as cutting tools–are present in this species. We discuss the implications that ours and previous great ape stone tool experiments have for understanding the initial stages of lithic technologies in our lineage

Production of Aspergillus niger GH1 tannase using solid-state fermentation

The production of tannase by Aspergillus niger GH1 in solid-state fermentation (SSF) was evaluated. Several concentrations of tannic acid (12.5, 25, 50 and 100 g/L) were tested in a model culture system. Column reactors were packed with polyurethane foam impregnated with liquid medium and inoculated with fungal spores. Tannase production was kinetically monitored by 48 h. Tannic acid uptake was spectrophotometrically measured and extracellular and intracellular tannase activities were assayed by HPLC-chromatography. Tannase activity increased with increasing concentration of tannic acid. Maximum extracellular and intracellular tannase activities (11.35 and 6.95 U/mL respectively) were recorded with 100 g/L of tannic acid. The substrate uptake was 100% at concentrations of 12.5, 25 and 50 g/L, while 74.4% was consumed in the presence of 100 g/L of tannic acid after 48 h of culture. These results suggest that high concentrations of tannins can be removed by SSF and tannase production can be reached in high levels.The present work was performed as part of a cooperative agreement between the Universidad Autonoma de Coahuila (UAdeC, Mexico) and the Universidade do Minho (UM, Portugal) within a specific international exchange program (VALNATURA project, alfa network from European Union) undertaken at the Biological Engineering Department (UM, Portugal) M A Cruz-Hernandez thanks to Concejo nacional de Ciencia y Tecnologia (CONACYT) the fellowship to study the doctoral program at the Department of Biotechnology (UAdeC

Los insectos comestibles: un recurso para el desarrollo local en el centro de México

Los insectos comestibles forman parte de los hábitos tradicionales de alimentación de México y el mundo, su preparación y consumo ha permanecido prácticamente igual durante siglos, pero en la actualidad, se observan cambios radicales debido, entre otras cosas a que se piensa que lo que cuenta es la cosmética de los alimentos de una manera predominante por lo cual se ha dejado de lado, además, con estos recursos naturales silvestres se tiene la posibilidad de iniciar grandes negocios al ser clasificados según el punto de vista occidental como “Alimentos exóticos”. La modificación de la apariencia y a la vez la conservación del valor cultural y el reconocimiento de la territorialidad de un producto, son factores de peso que permitirán la subsistencia y posterior aprovechamiento de los recursos naturales de las regiones. Tal es el caso del Escamol (huevos de hormiga- Liometopum apiculatum), insecto endémico de las inmediaciones de la cuenca de México, con el cual se pretende establecer las bases de reproducción -no en cautiverio- de una especie con gran demanda en el mercado gastronómico y que al paso del tiempo impulsará el desarrollo local de las regiones donde se produzca.Insectos comestibles, Teotihuacán, México, desarrollo local, tradiciones, escamoles., Agribusiness, Agricultural and Food Policy, Community/Rural/Urban Development, Food Consumption/Nutrition/Food Safety, Labor and Human Capital,

Preliminary culture conditions for Aspergillus niger GH1 tannase production in submerged culture

Nowadays, tannase is produce by submerged culture (SmC) being the enzyme obtained in an intracellular form resulting, as a consequence, in high production costs. To demonstrate that fungal tannase excretion is strongly influenced by the culture conditions, tannase production by Aspergillus niger GH1 on SmC using different bioreactors was evaluated. Two sets of experiments were conducted using in a first step a 1.5 L bioreactor and in a second step 100 mL erlenmeyer flasks. Modifications to culture conditions previously reported allowed to obtain positive results for tannase production in SmC, being the selected conditions: initial pH 5, temperature 35°C, initial substrate concentration 25g/L and agitation 200 rpm.A cultura submersa (SmC) é o processo empregado para produzir comercialmente a enzima tanasa, porém neste sistema da cultura, a tanasa é expressada principalmente de maneira intracelular o que representa custos de produção elevados. Para demonstrar que a excreção da tanasa do fungo está fortemente influenciada pelas condições da cultura, a produção da enzima tanase por Aspergillus niger GH1 em SmC foi avaliada. Dois conjuntos de experiências foram conduzidos usando em uma etapa um fermentador de 1.5 L e em uma segunda etapa matrazes (erlenmeyers) de 100 mL. As modificações às condições da cultura previamente descritas permitiram a obtenção de resultados positivos para a produção do tannase neste modo de produção, tendo sido definidas as seguintes condições de cultura: pH inicial 5, concentração inicial de substrato 25g/L, temperatura 35°C e agitação 200 rpm

Effects of a 16-Week Home-Based Strength Training Randomized Controlled Trial on Depression in Obese Latino Adolescent Boys

While the data has shown that the overall prevalence of depression is 6% in adolescents, these statistics are primarily based on white children. Latino children are more likely to suffer anxiety, depression and other mental health disorders compared to their non-Latino peers. While incidents are higher in Latino kids (22% suffer from depression), few receive treatment when compared to white children (8% vs 14% respectively). Given the prevailing burden and impact of mental health disorders in youth, it is essential that effective interventions are identified and implemented. PURPOSE: To assess the effects of a 16-week (2x/week) home-based strength training (HBST) program on the reduction of depression symptoms in obese Latino adolescent boys. METHODS: 32 Obese Latino boys aged 14-17 years, were recruited, and randomly assigned to one of two groups: 1) Control (n=16) or 2) Home-Based Strength Training (n=16). C – No intervention. HBST – Progressive program consisted of a 2X weekly program for 16 weeks. Body Mass Index (BMI) percentiles for age and gender were determined using CDC age-appropriate cut-offs. Height and weight were measured using a beam medical scale and wall-mounted stadiometer. Depression was assessed using the Center for Epidemiological Studies Depression scale (CES-D). All testing was performed before and after the 16-week intervention. RESULTS: A total of 30 boys (mean age = 15.5 + 0.9 years) completed the study. All thirty adolescents had a BMI in the 95% percentile. All participants attended \u3e85 % of the strength training sessions. Repeated Measures General Liner Model showed significant improvements in the intervention group only, with participants reporting an “increased happiness” (p=0.06) and increased “enjoyment in life” (p=0.009). In the intervention group, scores improved for questions such as “I felt depressed”, and “I felt sad”, although these improvements were not statistically significant (p=0.16, p=0.17 respectively). CONCLUSION: In a sample of obese male Latino adolescent males, small improvements were seen in feeling happy and enjoyment of life after a 16 week, 2x week home based strength training intervention. Future studies should consider strength training as an acceptable modality for improving mental health in obese Latino adolescent boys