Prehistoric psychotropic consumption in Andean Chilean mummies

Hallucinogenic plants are often regarded as the main source of psychoactive drugs in antiquity to reach deep altered states of consciousness^1,2^. Many researchers believe this was particularly true during the Tiwanaku empire expansion, circa (500-1000 A.D.), along the Atacama Desert of Chile. Highly decorated snuffing tablets and tubes are often found as grave goods during this period^3,4,5,6,7,8^. Until now the type of drugs consumed in this paraphernalia has been unclear. From the modern city of Arica, naturally mummified human bodies with abundant hair provided a unique opportunity to test for hallucinogenic plants consumed in Andean prehistory. Analysis by gas chromatography and mass spectrometry demonstrated the presence of harmine. The Banisteriopsis vine, commonly called Ayahuasca, was the probable source. This is the first confirmed evidence of psychoactive plant consumption in pre-Hispanic Andean populations along the Atacama coastal region. Of the 32 mummy hair samples analyzed 3 males tested positive for harmine. This alkaloid aids in the catalysis and synergic effects of powerful hallucinogenic drugs. The consumption of harmine was likely related to medicinal practices and not exclusively ingested by shamans. Another important aspect of this evidence is that Banisteriopsis is an Amazon plant. It does not grow in the Atacama coastal region. Thus, our findings reveal extensive plant trade networks in antiquity between the coast, desert, highlands, and Amazon basin. The excellent preservation of human organic specimens, the use of gas chromatography and mass spectrometry allowed us to map and demonstrate the consumption of psychoactive compound plants in Andean prehistory. In addition, our findings open the door for future studies to debate the consumption and social role of ancient psychoactive and hallucinogenic plants

Relación entre estado de conocimiento en fracciones y problemas descriptivos de fracciones

Este trabajo forma parte de un estudio que pretende examinar la relación entre las habilidades en fracciones de los escolares y su desempeño en la resolución de los problemas descriptivos de fracciones. Para ello se realiza un análisis descriptivo e inferencial de los datos obtenidos en una muestra de 85 estudiantes de 2º de Grado en Magisterio de la U. de Valencia a los que se les ha aplicado un test inicial de conocimiento genérico de las habilidades con fracciones y se les ha planteado un tipo específico de problemas descriptivos de fracciones, el de fracciones encadenadas por el complemento aritmético

Internet gambling: : A critical review of behavioural tracking research

This paper reviews and analyzes studies that are focused on Internet gambling with the use of behavioural tracking and big data to identify gambling behaviour. The behaviour of gamblers has been extensively studied and much has been published on the subject. The vast majority of research has relied on self-reported gambling behaviour or case study research. With the advent of the Internet, however, it has become possible for researchers to remotely study the real behaviour of gamblers. The goal has been to empirically describe playing behaviour in several conditions and contexts. Existing research, conducted since the 2000s, focuses on several forms of gambling such as sports betting, casino, poker, and lottery, but there is still only a concise body of research on gambling behaviour with the use of Internet gambling tracking data. Most studies are based on the same databases, meaning that a few companies and websites were the basis for most of the research produced so far. It is important to explore new sources of information, methodologies, and approaches to enrich discussion and contribute to a better understanding of this field. The empirical analysis of gambling behaviour with the use of tracking data was found to greatly contribute to the understanding of player behaviour, despite existing limitations and problems. Considering that Internet gambling behavioural tracking is still a fairly recent phenomenon, much can still be done to further develop this field of research.info:eu-repo/semantics/publishedVersio

Bioethics and the Law in Mexico

The results of an empirical study show that,taken as a group, physicians in Mexico do not know what is legal and what is not legal with respect to certain areas of clinical practice.  A number of legal cases are cited showing the ways in which the legal system is ineffective with respect to providing guidance on bioethicalissues.  We conclude that physicians in Mexico do not know what is legal and what is illegal with respect to bioethics because they cannot know (the law is unclear) and because they do not need to know (there is no effective legal precedent or enforcement).  We suggest that the way forward must be through institutional policies establishing standards that depend only upon the traditional contract for medical care

Bifurcation Phenomena in Two-Dimensional Piecewise Smooth Discontinuous Maps

In recent years the theory of border collision bifurcations has been developed for piecewise smooth maps that are continuous across the border, and has been successfully applied to explain nonsmooth bifurcation phenomena in physical systems. However, many switching dynamical systems have been found to yield two-dimensional piecewise smooth maps that are discontinuous across the border. The theory for understanding the bifurcation phenomena in such systems is not available yet. In this paper we present the first approach to the problem of analysing and classifying the bifurcation phenomena in two-dimensional discontinuous maps, based on a piecewise linear approximation in the neighborhood of the border. We explain the bifurcations occurring in the static VAR compensator used in electrical power systems, using the theory developed in this paper. This theory may be applied similarly to other systems that yield two-dimensional discontinuous maps

Shrinking Point Bifurcations of Resonance Tongues for Piecewise-Smooth, Continuous Maps

Resonance tongues are mode-locking regions of parameter space in which stable periodic solutions occur; they commonly occur, for example, near Neimark-Sacker bifurcations. For piecewise-smooth, continuous maps these tongues typically have a distinctive lens-chain (or sausage) shape in two-parameter bifurcation diagrams. We give a symbolic description of a class of "rotational" periodic solutions that display lens-chain structures for a general $N$-dimensional map. We then unfold the codimension-two, shrinking point bifurcation, where the tongues have zero width. A number of codimension-one bifurcation curves emanate from shrinking points and we determine those that form tongue boundaries.Comment: 27 pages, 6 figure

Bifurcations in the Lozi map

We study the presence in the Lozi map of a type of abrupt order-to-order and order-to-chaos transitions which are mediated by an attractor made of a continuum of neutrally stable limit cycles, all with the same period.Comment: 17 pages, 12 figure

Kind Inference for the FreeST Programming Language

We present a kind inference algorithm for the FREEST programming language. The input to the algorithm is FREEST source code with (possibly part of) kind annotations replaced by kind variables. The algorithm infers concrete kinds for all kind variables. We ran the algorithm on the FREEST test suite by first replacing kind annotation on all type variables by fresh kind variables, and concluded that the algorithm correctly infers all kinds. Non surprisingly, we found out that programmers do not choose the most general kind in 20% of the cases.Comment: In Proceedings PLACES 2023, arXiv:2304.0543