Beliefs about others' intentions determine whether cooperation is the faster choice

Is collaboration the fast choice for humans? Past studies proposed that cooperation is a behavioural default, based on Response Times (RT) findings. Here we contend that the individual’s reckoning of the immediate social environment shapes her predisposition to cooperate and, hence, response latencies. In a social dilemma game, we manipulate the beliefs about the partner’s intentions to cooperate and show that they act as a switch that determines cooperation and defection RTs; when the partner’s intention to cooperate is perceived as high, cooperation choices are speeded up, while defection is slowed down. Importantly, this social context effect holds across varying expected payoffs, indicating that it modulates behaviour regardless of choices’ similarity in monetary terms. Moreover, this pattern is moderated by individual variability in social preferences: Among conditional cooperators, high cooperation beliefs speed up cooperation responses and slow down defection. Among free-riders, defection is always faster and more likely than cooperation, while high cooperation beliefs slow down all decisions. These results shed new light on the conflict of choices account of response latencies, as well as on the intuitive cooperation hypothesis, and can help to correctly interpret and reconcile previous, apparently contradictory results, by considering the role of context in social dilemmas

Strong, bold, and kind : Self-control and cooperation in social dilemmas

Financial support from the Swedish Research Council (Vetenskapsrådet), from Formas through the program Human Cooperation to Manage Natural Resources (COMMONS), and the Ideenfonds of the University of Munich is gratefully acknowledged.We develop a model that relates self-control to cooperation patterns in social dilemmas, and we test the model in a laboratory public goods experiment. As predicted, we find a robust association between stronger self-control and higher levels of cooperation, and the association is at its strongest when the decision maker’s risk aversion is low and the cooperation levels of others high. We interpret the pattern as evidence for the notion that individuals may experience an impulse to act in self-interest—and that cooperative behavior benefits from self-control. Free-riders differ from other contributor types only in their tendency not to have identified a self-control conflict in the first place.PostprintPeer reviewe

Forage:Concentrate Ratio Effects on In Vivo Digestibility and In Vitro Degradability of Horse’s Diet

Determination of digestibility represents the first step for the evaluation of the net energy content of feed for livestock animals. The aim of this study was to evaluate the in vivo digestibility and in vitro degradability of five diets characterized by different forage/concentrate ratios (F:C) in horses. The in vitro degradability was determined by the Gas Production Technique (GPT), using as an inoculum source the feces of the same subjects used for the in vivo test. Five diets consisting of poliphyte hay, straw and grains of barley and oats with a different F:C ratio [90/10 (Diet 1); 78/22 (Diet 2); 68/32 (Diet 3); 60/40 (Diet 4); 50/50 (Diet 5) were formulated and administered in succession, starting with Diet 1. In the in vivo results, no significant differences emerged, despite the different F:C content. In in vitro fermentation, four diets out of the five (2, 3, 4, 5) presented a similar trend of the curve of gas production, showing good activity of the fecal micro population during the first hours of incubation. An important correlation between gas and Volatile Fatty Acid (VFA) were found, suggesting that the processes linked to the micro population deriving from the horse’s caecum follow metabolic pathways whose products can be modeled in the same way as for the rumen. The GPT could represent the correct method for studying the nutritional characteristics of feed for horses, using feces as the source of inoculum, even if further investigations must be performed to improve the technique

Obesity-Related Oxidative Stress: the Impact of Physical Activity and Diet Manipulation

Obesity-related oxidative stress, the imbalance between pro-oxidants and antioxidants (e.g., nitric oxide), has been linked to metabolic and cardiovascular disease, including endothelial dysfunction and atherosclerosis. Reactive oxygen species (ROS) are essential for physiological functions including gene expression, cellular growth, infection defense, and modulating endothelial function. However, elevated ROS and/or diminished antioxidant capacity leading to oxidative stress can lead to dysfunction. Physical activity also results in an acute state of oxidative stress. However, it is likely that chronic physical activity provides a stimulus for favorable oxidative adaptations and enhanced physiological performance and physical health, although distinct responses between aerobic and anaerobic activities warrant further investigation. Studies support the benefits of dietary modification as well as exercise interventions in alleviating oxidative stress susceptibility. Since obese individuals tend to demonstrate elevated markers of oxidative stress, the implications for this population are significant. Therefore, in this review our aim is to discuss (i) the role of oxidative stress and inflammation as associated with obesity-related diseases, (ii) the potential concerns and benefits of exercise-mediated oxidative stress, and (iii) the advantageous role of dietary modification, including acute or chronic caloric restriction and vitamin D supplementation

Nanoengineering of Chitosan Sponges Via Atomic Layer Deposition of ZnO for Water Remediation Technologies

Low-cost, millimeter-thick chitosan-based sponges are engineered with zinc oxide (ZnO) using atomic layer deposition (ALD) to create a multifunctional nanocomposite for the potential application in water remediation and self-regeneration via solid-state photocatalysis. Initially, non-porous chitosan films served as control samples to study the ZnO growth mechanism and its impact on the biopolymer's optical and chemical properties. Subsequently, porous chitosan sponges are engineered to further explore the photocatalyst growth and infiltration into the porous matrix. The characterization of the chitosan/ZnO hybrid material is performed using spectroscopic ellipsometry, X-ray photoelectron spectroscopy, UV–vis, photoluminescence, and infrared spectroscopy, analyzing the effect of varying the number of ALD cycles, resulting in different ZnO thicknesses in the range of 5–30 nm on the chitosan matrix. A reaction-limited growth model is found and strong interactions between ZnO and chitosan amino groups significantly enhance the stability in water and impart photocatalytic features. Adsorption tests using Direct Blue 78 dye demonstrated high removal efficiency, with capacities up to 2000 mg g−1, surpassing pristine chitosan sponges, which degrade in water. Electrostatic interactions between dye sulfonate groups and protonated chitosan amino moieties are identified as key to this performance. Preliminary photocatalytic experiments using Naproxen confirms the ZnO-coated sponges' ability to degrade pollutants, showcasing ALD as a key technology for producing bio-based, photoactive materials for sustainable water treatment

Correlação entre as alterações osteocondrais evidenciadas à ressonância magnética e a progressão da doença

PURPOSE: To determine the consequences of the chronic use of systemic corticosteroids in children with juvenile rheumatoid arthritis by means of evaluating osteochondral effects depicted by magnetic resonance imaging. PATIENTS AND METHODS: We reviewed clinical and magnetic resonance imaging findings in 69 children (72 knees) with juvenile rheumatoid arthritis. Two groups were studied. Group I: 34 (49.3%) children had previous or current use of systemic corticotherapy (22 girls; 12 boys; mean age: 11.3 years; mean disease duration: 5.9 years; mean corticotherapy duration: 2.9 years; mean cumulative dose of previous corticosteroids: 5000 mg); Group II: 35 (50.7%) children had no previous use of corticosteroids (27 girls; 8 boys; mean age: 11.7 years; mean disease duration: 5.3 years). The groups were compared statistically. RESULTS: In the group that had received corticotherapy (Group I), osteochondral abnormalities were significantly correlated to long-standing disease (>;3.5 years; pOBJETIVO: Determinar as conseqüências do uso crônico de corticosteróides sistêmicos em crianças com artrite reumatóide juvenil através da avaliação dos efeitos osteocondrais à ressonância magnética. PACIENTES E MÉTODOS: Achados clínicos e imaginológicos (ressonância magnética) de 72 joelhos em 69 crianças com artrite reumatóide juvenil foram revisados. Trinta e quatro (49.3%) pacientes fizeram uso prévio de corticoterapia sistêmica (22 pacientes do sexo feminino; 12 pacientes do sexo masculino; idade média: 11.3 anos; duração média da doença: 5.9 anos; duração média da corticoterapia: 2.9 anos; dose média cumulativa de corticosteróides: 5000 mg); 35 (50.7%) pacientes não haviam feito uso prévio de corticoterapia sistêmica (27 pacientes do sexo feminino; 8 pacientes do sexo masculino; idade média: 11.7 anos; duração média da doença: 5.3 anos). RESULTADOS: No grupo que recebeu corticoterapia sistêmica prévia (Grupo I) a presença de alterações osteocondrais à ressonância magnética relacionou-se de uma forma estatisticamente significativa com longo tempo de duração da doença (>;3.5 years;

Fully Metal-Coated Scanning Near-Field Optical Microscopy Probes with Spiral Corrugations for Superfocusing under Arbitrarily Oriented Linearly Polarised Excitation

We study the effect of a spiral corrugation on the outer surface of a fully metal-coated scanning near-field optical microscopy (SNOM) probe using the finite element method. The introduction of a novel form of asymmetry, devoid of any preferential spatial direction and covering the whole angular range of the originally axisymmetric tip, allows attaining strong field localization for a linearly polarised mode with arbitrary orientation. Compared to previously proposed asymmetric structures which require linearly polarised excitation properly oriented with respect to the asymmetry, such a configuration enables significant simplification in mode injection. In fact, not only is the need for the delicate procedure to generate radially polarised beams overcome, but also the relative alignment between the linearly polarised beam and the tip modification is no longer critical

A quantitative description of the transition between intuitive altruism and rational deliberation in iterated Prisoner's Dilemma experiments

What is intuitive: pro-social or anti-social behaviour? To answer this fundamental question, recent studies analyse decision times in game theory experiments under the assumption that intuitive decisions are fast and that deliberation is slow. These analyses keep track of the average time taken to make decisions under different conditions. Lacking any knowledge of the underlying dynamics, such simplistic approach might however lead to erroneous interpretations. Here we model the cognitive basis of strategic cooperative decision making using the Drift Diffusion Model to discern between deliberation and intuition and describe the evolution of the decision making in iterated Prisoner's Dilemma experiments. We find that, although initially people's intuitive decision is to cooperate, rational deliberation quickly becomes dominant over an initial intuitive bias towards cooperation, which is fostered by positive interactions as much as frustrated by a negative one. However, this initial pro-social tendency is resilient, as after a pause it resets to the same initial value. These results illustrate the new insight that can be achieved thanks to a quantitative modelling of human behavior