פרסומים

The edges of stone tools have significant technological and functional implications. The nature of these edges–their sharpness, whether they are concave or convex, and their asymmetry–reflect how they were made and how they could be used. Similarly, blunt portions of a tool’s perimeter hint at how they could have been grasped or hafted and in which directions force could be applied. However, due to the difficulty in accurately measuring the complex 3D geometry of tool edges with traditional methods, their attributes are often overlooked. When they are analyzed, they have traditionally been assessed with visual qualitative categories or unreliable physical measurements. We introduce new computational 3D methods for automatically and repeatably measuring key attributes of stone tool edges. These methods allow us to automatically identify the 3D perimeter of tools, segment this perimeter according to changes in edge angles, and measure these discrete edge segments with a range of metrics. We test this new computational toolkit on a large sample of 3D models of handaxes from the later Acheulean of the southern Levant. Despite these handaxes being otherwise technologically and morphologically similar, we find marked differences in the amount of knapped outline, edge angle, and the concavity of their edges. We find many handaxes possess blunt portions of perimeter, suitable for grasping, and some handaxes even possess more than one discrete sharp edge. Among our sample, sites with longer occupations and more diverse toolkits possessed handaxes with more diverse edges. Above all, this paper offers new methods for computing the complex 3D geometry of stone tool edges that could be applied to any number of artifact types. These methods are fully automated, allowing the analysis and visualization of entire assemblages. 

The present review deals with two main ingredients of energy/power drinks: B vitamins and glucuronolactone and their possible effect on the immune system. There is a strong relationship between the recommended daily dose of selected B vitamins and a functional immune system. Regarding specific B vitamins: (1) Riboflavin is necessary for the optimization of reactive oxygen species (ROS) in the fight against bacterial infections caused by Staphylococcus aureus and Listeria monocytogenes. (2) Niacin administered within normal doses to obese rats can change the phenotype of skeletal fibers, and thereby affect muscle metabolism. This metabolic phenotype induced by niacin treatment is also confirmed by stimulation of the expression of genes involved in the metabolism of free fatty acids (FFAs) and oxidative phosphorylation at this level. (3) Vitamin B5 effects depend primarily on the dose, thus large doses can cause diarrhea or functional disorders of the digestive tract whereas normal levels are effective in wound healing, liver detoxification, and joint health support. (4) High vitamin B6 concentrations (>2000 mg per day) have been shown to exert a significant negative impact on the dorsal root ganglia. Whereas, at doses of approximately 70 ng/mL, sensory symptoms were reported in 80% of cases. (5) Chronic increases in vitamin B12 have been associated with the increased incidence of solid cancers. Additionally, glucuronolactone, whose effects are not well known, represents a controversial compound. (6) Supplementing with D-glucarates, such as glucuronolactone, may help the body’s natural defense system function better to inhibit different tumor promoters and carcinogens and their consequences. Cumulatively, the present review aims to evaluate the relationship between the selected B vitamins group, glucuronolactone, and the immune system and their associations to bioavailability, doses, and efficiency.

Sensory neurons specialize in detecting and signaling the presence of diverse environmental stimuli. Neuronal injury or disease may undermine such signaling, diminishing the availability of crucial information. Can animals distinguish between a stimulus not being present and the inability to sense that stimulus in the first place? To address this question, we studied Caenorhabditis elegans nematode worms that lack gentle body touch sensation due to genetic mechanoreceptor dysfunction. We previously showed that worms can compensate for the loss of touch by enhancing their sense of smell, via an FLP-20 neuropeptide pathway. Here, we find that touch-deficient worms exhibit, in addition to sensory compensation, also cautious-like behavior, as if preemptively avoiding potential undetectable hazards. Intriguingly, these behavioral adjustments are abolished when the touch neurons are removed, suggesting that touch neurons are required for signaling the unavailability of touch information, in addition to their conventional role of signaling touch stimulation. Furthermore, we found that the ASE taste neurons, which similarly to the touch neurons, express the FLP-20 neuropeptide, exhibit altered FLP-20 expression levels in a touch-dependent manner, thus cooperating with the touch circuit. These results imply a novel form of neuronal signaling that enables C. elegans to distinguish between lack of touch stimulation and loss of touch sensation, producing adaptive behavioral adjustments that could overcome the inability to detect potential threats.

 

Empathy, the capacity to share others’ emotional experiences, has been proposed as a key motivation for altruistic behavior in both humans and animals. Sharing another’s emotional experience may generate a self-embodied simulation of their emotional state, fostering understanding and promoting prosocial behavior. Vicarious pain responders report sensing physical pain when observing others in pain. Whether this ability extends to emotional experiences remains unexplored. Using both questionnaires and ecologically valid behavioral tasks, we explored whether vicarious pain responders differ from nonresponders in empathic abilities and prosocial behavior. Participants watched video clips of people describing a negative emotional life event. We operationalized several empathic abilities and responses (empathic accuracy, affective synchrony, emotional reaction, and empathic motivation) based on participants’ and targets’ responses during and after watching the videos. Participants were also engaged in a donation task measuring tendency for prosocial behavior. Findings reveal that compared to nonresponders, vicarious pain responders exhibit enhanced empathic accuracy, intensified emotional reactions to others’ emotional pain, and a greater motivation to communicate with the target. This study marks the first behavioral evidence showcasing vicarious pain responders’ empathic abilities, reactions, and motivation in response to nonphysical pain of others, expanding our knowledge of this phenomenon and its association with broader empathic abilities.

Abstract

Intragroup empathy is vital for resilience. However, it is often impaired in advantaged-dominated environments when one adopts advantaged-group characteristics to climb the social ladder. The current work examines contextual factors that may affect intragroup empathy: the motivation behind adopting the advantaged-group characteristics, and negative encounters with members of the advantaged group. We hypothesized that coercively, versus willingly, adopting advantaged-group characteristics will increase intragroup empathy both when the outcomes are negative and positive. We further hypothesized that a negative encounter with an advantaged-group member would increase intragroup empathy, compared to no encounter. In three studies, Palestinian students in Israeli academia were assigned to read scripts depicting the academic experience of a Palestinian student adopting advantaged-group characteristics. We tested (a) the effects of motivation following a negative outcome (N = 182); (b) the effects following a positive outcome (N = 205); and (c) the interaction between a negative encounter with an advantaged-group member and motivation, and its effect on intragroup empathy (N = 282). Intragroup empathy was higher in the coerced condition compared to the free-willing condition both for negative and positive outcomes. A negative encounter with an advantaged-group member increased intragroup empathy in the willing condition. By illuminating contextual variables that shape intragroup empathy, this research shows that impairment in intragroup empathy is not inevitable. This work may serve as a foundation for future interventions.