Voluntary food sharing in pinyon jays: The role of reciprocity and dominance

Food sharing offers a clear example of prosocial behavior, in which one individual’s actions benefit another. Researchers have proposed a range of hypotheses that explain why food sharing may occur among unrelated individuals. Two such hypotheses, reciprocity and dominance, have been tested in many species, including fish, corvids, rats, bats, and primates, showing that (1) recipients sometimes reciprocate sharing back to previous donors and (2) dominant individuals share more than subordinates. Although primates dominate the study of prosocial behavior, active donation of food is actually quite rare in primates. In contrast, several corvid species spontaneously share food much more frequently. Here, we explored the role of reciprocity and dominance in spontaneous food sharing among male pinyon jays (Gymnorhinus cyanocephalus); a North American corvid species that exhibits high levels of social complexity. Unlike much of the previous work, we tested prosocial behavior among unrelated, non-pair bonded adults. We observed high levels of active sharing, and donors showed clear preferences with whom they shared. We found no evidence that pinyon jays reciprocated shares in either the short or long term. This was true for both sharing within-dyads (direct reciprocity) and sharing irrespective of most recent partner identity (generalized reciprocity). However, dominance influenced sharing in one of our groups, with dominant individuals sharing more than subordinates. This study highlights corvids as a fruitful model for the study of the proximate mechanisms underlying naturally occurring prosocial behaviors

Voluntary food sharing in pinyon jays: The role of reciprocity and dominance

Food sharing offers a clear example of prosocial behavior, in which one individual’s actions benefit another. Researchers have proposed a range of hypotheses that explain why food sharing may occur among unrelated individuals. Two such hypotheses, reciprocity and dominance, have been tested in many species, including fish, corvids, rats, bats, and primates, showing that (1) recipients sometimes reciprocate sharing back to previous donors and (2) dominant individuals share more than subordinates. Although primates dominate the study of prosocial behavior, active donation of food is actually quite rare in primates. In contrast, several corvid species spontaneously share food much more frequently. Here, we explored the role of reciprocity and dominance in spontaneous food sharing among male pinyon jays (Gymnorhinus cyanocephalus); a North American corvid species that exhibits high levels of social complexity. Unlike much of the previous work, we tested prosocial behavior among unrelated, non-pair bonded adults. We observed high levels of active sharing, and donors showed clear preferences with whom they shared. We found no evidence that pinyon jays reciprocated shares in either the short or long term. This was true for both sharing within-dyads (direct reciprocity) and sharing irrespective of most recent partner identity (generalized reciprocity). However, dominance influenced sharing in one of our groups, with dominant individuals sharing more than subordinates. This study highlights corvids as a fruitful model for the study of the proximate mechanisms underlying naturally occurring prosocial behaviors

A Search Engine Optimization Recommender System

International audienceSearch Engine Optimization reefers to the process of im- proving the position of a given website in a web search engine results. This is typically done by adding a set of parameters and metadata to the hypertext files of the website. As nowadays the majority of the web-content creators are non-experts, automation of the search en- gine optimization process becomes a necessity. On this regard, this paper presents a recommender system to improve search engine op- timization based on the site’s content and creator’s preferences. It exploits text analysis for labels and tags, artificial intelligence for deducing content intention and topics, and case-based reasoning for generating recommendations of parameters and metadata. Recom- mendations are given in natural language using a predefined set of sentences

Is the Banana Ripe? Andean Bear–Human Conflict in a Protected Area of Colombia

The Andean bear (Tremarctos ornatus; bear) is endemic to the tropical Andes Mountains of South America. Previous assessments predict that bear populations will decline by \u3e30% in the next 30 years. The species may face the greatest threats within its historical distribution in Colombia where rapid agricultural expansion into natural habitats is increasing human–bear conflicts. Between April 2017 and March 2018, we studied bear feeding behavior on plantain (Musa sapientum) and banana (M. paradisiaca) crops within the Barbas-Bremen protected area in the central mountain range of Colombia to describe the magnitude of crop damage, economic losses, and spatial distribution of feeding sites where human–bear conflicts would most likely occur. We also identified all affected farmers and used structured interviews to determine their attitudes toward the bears and their conservation. We recorded 237 damaged plants and identified 57 bear feeding area locations on 9 farms. Bear damage consisted of bites to the trunk of each plant and consumption of the centers. The damage polygon covered 198 ha, and it was located in the northwestern portion of the protected area. Although we estimated that the magnitude of crop consumption by bears and social and economic dimensions of damage caused by the species in Colombia. Our research also provides insights on how human–bear conflicts may be mitigated in the study area

Diseño del encofrado para muros usando encofrados modulares

Concrete is one of the most versatile materials used in construction. At present, it is extensively employed in the industry as it can be molded in almost any shape through rigid molds called formwork. The arrangement of the different elements that compose the formwork and its associated restrictions pose interesting computational challenges that directly impact the construction industry. In this article, we propose the implementation of a model with constraints that generates a formwork layout for rectilinear walls using modular forms. This approach is based on the decomposition of walls and their representation as instances of the change-making problem. For that purpose, we used the concept of oriented rectangular decomposition to simplify the problem input and address the solution as a Constraint Optimization Problem (COP). The experiments with test inputs provided solutions in less than 200 seconds, thus offering a practical and efficient approach to the complex task of formwork design.  El concreto u hormigón es uno de los materiales más versátiles usados en la construcción.  En la actualidad, se usa extensivamente en la industria, ya que puede ser moldeado de formas casi arbitrarias a través de moldes rígidos denominados encofrados. La manera en que se disponen los distintos elementos para formar el encofrado y las restricciones asociadas, genera retos computacionales interesantes que impactan directamente la industria de la construcción. En este artículo se propone la implementación de un modelo de restricciones que genera encofrados para muros rectilíneos usando formaletas modulares. Este enfoque se basa en la descomposición de muros y su representación en instancias del problema de cambio de monedas. Para este propósito, se utiliza el concepto de descomposición rectangular orientada para simplificar la entrada del problema y abordar la solución como un problema de optimización por restricciones (COP). Los experimentos con entradas de prueba ofrecen soluciones en tiempos inferiores a 200 segundos, cuyo resultado es un enfoque práctico y eficiente para la compleja tarea del diseño de encofrados

Coastal subsidence increases vulnerability to sea level rise over twenty first century in Cartagena, Caribbean Colombia

Cartagena is subsiding at a higher rate compared to that of global climate-driven sea level rise. We investigate the relative sea level rise (RSLR) and the influence of vertical land movements in Cartagena through the integration of different datasets, including tide gauge records, GPS geodetic subsidence data, and Interferometric Synthetic Aperture Radar (InSAR) observations of vertical motions. Results reveal a long-term rate (\u3e 60 years) of RSLR of 5.98 ± 0.01 mm/yr. The last two decades exhibited an even greater rate of RSLR of 7.02 ± 0.06 mm/yr. GPS subsidence rates range between − 5.71 ± 2.18 and − 2.85 ± 0.84 mm/yr. InSAR data for the 2014–2020 period show cumulative subsidence rates of up to 72.3 mm. We find that geologically induced vertical motions represent 41% of the observed changes in RSLR and that subsidence poses a major threat to Cartagena’s preservation. The geodetic subsidence rates found would imply a further additional RSLR of 83 mm by 2050 and 225 mm by 2100. The Colombian government should plan for the future and serve as an example to similar cities across the Caribbean

Re-evaluating sheet erosion rates in a popular trekking trail located at the Spanish Central System

Degradation of walking tracks, mainly due to sheet erosion associated with hiking activities, damages the natural and recreational value of protected natural areas. Senda Schmidt is a popular trail located on the northern slope of the Sierra de Guadarrama (Central Spanish System), that shows high denudation morphologies on account of accelerated soil-erosion processes basically caused by human influence (trampling by continuous trekking), resulted in exposed roots. Previous works have used dendrogeomorphological methods in this trail to estimate rates of sheet erosion based on the changing morphology of tree rings (from concentric to eccentric) when root is exposed. This study aims to evaluate soil erosion reconstructing the first year of root exposure by analyzing changes in wood anatomical parameters within growth rings. Additionally, different multivariate statistical approaches were used in order to determinate the influence of different environmental factors affecting the variation in velocity of the sheet erosion processes

Coastal subsidence increases vulnerability to sea level rise over twenty first century in Cartagena, Caribbean Colombia

Cartagena is subsiding at a higher rate compared to that of global climate-driven sea level rise. We investigate the relative sea level rise (RSLR) and the influence of vertical land movements in Cartagena through the integration of different datasets, including tide gauge records, GPS geodetic subsidence data, and Interferometric Synthetic Aperture Radar (InSAR) observations of vertical motions. Results reveal a long-term rate (\u3e 60 years) of RSLR of 5.98 ± 0.01 mm/yr. The last two decades exhibited an even greater rate of RSLR of 7.02 ± 0.06 mm/yr. GPS subsidence rates range between − 5.71 ± 2.18 and − 2.85 ± 0.84 mm/yr. InSAR data for the 2014–2020 period show cumulative subsidence rates of up to 72.3 mm. We find that geologically induced vertical motions represent 41% of the observed changes in RSLR and that subsidence poses a major threat to Cartagena’s preservation. The geodetic subsidence rates found would imply a further additional RSLR of 83 mm by 2050 and 225 mm by 2100. The Colombian government should plan for the future and serve as an example to similar cities across the Caribbean

Overview of processing techniques for surface electromyography signals

Surface electromyography (sEMG) is a technology to assess muscle activation, which is an important component in applications related to diagnosis, treatment, progression assessment, and rehabilitation of specific individuals' conditions. Recently, sEMG potential has been shown, since it can be used in a non-invasive manner; nevertheless, it requires careful signal analysis to support health professionals reliably. This paper briefly described the basic concepts involved in the sEMG, such as the physiology of the muscles, the data acquisition, the signal processing techniques, and classification methods that may be used to identify disorders or signs of abnormalities according to muscular patterns. Specifically, classification methods encompass digital signal processing techniques and machine learning with high potential in the field. We hope that this work serves as an introduction to researchers interested in this field.Comment: 11 pages, 7 figure

Female rats display higher methamphetamine-primed reinstatement and c-Fos immunoreactivity than male rats

Methamphetamine (meth) dependence is often characterized by persistent and chronic relapse (i.e., return to drug use). Previous work suggests females may be at greater risk to relapse. In this study, we extended this limited evidence and identified sex-dependent neural substrates related to meth-triggered reinstatement. Male and female Sprague-Dawley rats were implanted with indwelling jugular catheters. Half of the rats were then trained to self-administer meth (0.05 mg/kg/inf); the other half self-administered saline during 21 daily sessions (2 h). Rats were then given 12 extinction sessions. Twenty-four hours after the last extinction session, rats received reinstatement testing. Half of the rats received a meth-prime (0.3 mg/kg, IP) injection and the remaining rats received a saline injection. This design resulted in 4 separate groups for each sex, allowing for careful investigation of brain regions related to meth-triggered reinstatement. Brains were harvested following the reinstatement session and c-Fos immunoreactivity was measured in multiple brain regions. Meth triggered reinstatement in both sexes and this effect was more robust in females compared to males. Significant sex differences were detected. Females showed greater c-Fos immunoreactivity in the cingulate cortex area 1, lateral orbitofrontal cortex, prelimbic cortex, caudate-putamen, nucleus accumbens core and shell, and central nucleus of the amygdala following meth-primed reinstatement