Age-dependent cognitive inflexibility in great apes

The ability to suppress and/or change behaviour on the basis of negative feedback, often conceptualized as cognitive flexibility, has rarely been investigated in nonhuman great apes across a broad age range. In this study, 25 chimpanzees, Pan troglodytes, eight bonobos, Pan paniscus, seven orang-utans, Pongo abelii, and three gorillas, Gorilla gorilla, whose ages ranged from 5 to 48 years, were presented with a transparent Plexiglas rectangular box horizontally attached to their cage mesh. A square container, 7.5 cm2, fixed inside the apparatus contained a food reward (i.e. a grape). While the container rested on its central position the grape was not accessible. To retrieve the grape the subjects needed to grasp the handle connected to the reward container and displace it sideways to reach one of the lateral access windows. Subjects were intensively trained to displace the handle to a specific side (right or left, depending on the group) and then the rewarded side was reversed during the test. Performance in this reversal task did not differ significantly between species. However, a U-shaped relation between age and perseverative responding (i.e. moves to the previously rewarded side) was observed, extending findings with humans to our closest living primate relatives. (C) 2015 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.PostprintPeer reviewe

Repeated innovation in great apes

Innovation has been defined as a solution to a novel problem or a novel solution to an old problem. The second part of this definition requires the inhibition of previously learnt solution strategies before a novel solution can be found. Therefore, inventing novel solutions for an old problem is considered to be particularly difficult. We investigated the ability of great apes to produce multiple new solutions to a task after each of those solutions became obsolete. We presented all four nonhuman great ape species with a task consisting of extracting a food reward from a puzzle box. Initially, the task could be solved in three different ways that varied in difficulty. After subjects discovered the first solution, we allowed them to use it for some trials and then it became obsolete. If the apes could overcome their initial response and find the next solution, we again allowed them to use it for some time and once again it became obsolete. The final step consisted of finding the third solution to secure the food reward. We found that all species except orang-utans, Pongo abelii, were able to solve all versions of the problem. Furthermore, they overcame the obsolete techniques quickly and efficiently, indicating high degrees of behavioural flexibility and inhibitory control. In contrast to previous research on social learning, our results suggest that great apes are not conservative and adjust their behaviour flexibly when the physical constraints of a task change. (C) 2012 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.</p

Great Apes Select Tools on the Basis of Their Rigidity

Wild chimpanzees select tools according to their rigidity. However, little is known about whether choices are solely based on familiarity with the materials or knowledge about tool properties. Furthermore, it is unclear whether tool manipulation is required prior to selection or whether observation alone can suffice. We investigated whether chimpanzees (Pan troglodytes) (n = 9). bonobos (Pan paniscus)(n = 4), orangutans (Pongo pygmaeus) (n = 6), and gorillas (Gorilla gorilla) (n = 2) selected new tools on the basis of their rigidity. Subjects faced an out-of-reach reward and a choice of three tools differing in color, diameter, material, and rigidity. We used 10 different 3-tool sets ( I rigid, 2 flexible). Subjects were unfamiliar with the tools and needed to select and use the rigid tool to retrieve the reward. Experiment I showed that subjects chose the rigid tool from the first trial with a 90% success rate. Experiments 2a and 2b addressed the role of manipulation and observation in tool selection. Subjects performed equally well in conditions in which they could manipulate the tools themselves or saw the experimenter manipulate the tools but decreased their performance if they could only visually inspect the tools. Experiment 3 showed that subjects could select flexible tools (as opposed to rigid ones) to meet new task demands. We conclude that great apes spontaneously selected unfamiliar rigid or flexible tools even after gathering minimal observational information.</p

Intel, Guadalajara Design Center

Proyecto de Aplicación Profesional realizado en la empresa Intel en el área de Makers, en la que se trabajó en la coordinación, planeación y difusión de proyectos. Además, se laboró como el encargado del laboratorio de Proof of Concept

Rationale, design, and baseline characteristics in Evaluation of LIXisenatide in Acute Coronary Syndrome, a long-term cardiovascular end point trial of lixisenatide versus placebo

BACKGROUND: Cardiovascular (CV) disease is the leading cause of morbidity and mortality in patients with type 2 diabetes mellitus (T2DM). Furthermore, patients with T2DM and acute coronary syndrome (ACS) have a particularly high risk of CV events. The glucagon-like peptide 1 receptor agonist, lixisenatide, improves glycemia, but its effects on CV events have not been thoroughly evaluated. METHODS: ELIXA (www.clinicaltrials.gov no. NCT01147250) is a randomized, double-blind, placebo-controlled, parallel-group, multicenter study of lixisenatide in patients with T2DM and a recent ACS event. The primary aim is to evaluate the effects of lixisenatide on CV morbidity and mortality in a population at high CV risk. The primary efficacy end point is a composite of time to CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. Data are systematically collected for safety outcomes, including hypoglycemia, pancreatitis, and malignancy. RESULTS: Enrollment began in July 2010 and ended in August 2013; 6,068 patients from 49 countries were randomized. Of these, 69% are men and 75% are white; at baseline, the mean ± SD age was 60.3 ± 9.7 years, body mass index was 30.2 ± 5.7 kg/m(2), and duration of T2DM was 9.3 ± 8.2 years. The qualifying ACS was a myocardial infarction in 83% and unstable angina in 17%. The study will continue until the positive adjudication of the protocol-specified number of primary CV events. CONCLUSION: ELIXA will be the first trial to report the safety and efficacy of a glucagon-like peptide 1 receptor agonist in people with T2DM and high CV event risk

Global economic burden of unmet surgical need for appendicitis

Background There is a substantial gap in provision of adequate surgical care in many low- and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US $92 492 million using approach 1 and$73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was $95 004 million using approach 1 and$75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially