Investigating chronic pain as an in-group using the prisoner’s dilemma

Kinship is a strong predictor of altruism. However, chronic pain is a homeostatic threat to survival that creates a social in-group which we predicted would result in increased altruism over and above kinship, because it is driven by shared empathy. Participants included 139 individuals that were divided into a chronic pain or control group. Participants completed six Prisoner’s Dilemma scenarios with a sibling or chronic pain accomplice. Pain altruism and sibling altruism scores were calculated based on decisions to cooperate with or defect on an accomplice. A mixed ANOVA revealed that there were no significant differences between groups. The marginal difference between the groups suggests that chronic pain may create an in-group altruism that is just as strong as kinship

Alpha band prefrontal asymmetry does not underlie pain approach-avoidance: Results from two EEG studies

Pain research is often focused on escape from pain or approach of relief, yet individuals with chronic pain make complex choices to face their pain to satiate other drives (approach-avoidance conflicts). An abundance of research has indicated that prefrontal alpha band asymmetry (PFA) underlies approach-avoidance in general, but there is limited information about whether PFA underlies pain approach-avoidance conflicts. Electroencephalogram activity was recorded while 70 participants with chronic pain (n=33) and without chronic pain (n=37) approached/avoided stimuli containing simultaneous pain (low-high) and monetary reward (low-high). Findings from both studies revealed that approach-avoidance for pain stimuli is not accompanied by prefrontal asymmetry, irrespective of the presence of chronic pain

Mechanical Activation of a Multimeric Adhesive Protein Through Domain Conformational Change

The mechanical force-induced activation of the adhesive protein von Willebrand factor (VWF), which experiences high hydrodynamic forces, is essential in initiating platelet adhesion. The importance of the mechanical force-induced functional change is manifested in the multimeric VWF's crucial role in blood coagulation, when high fluid shear stress activates plasma VWF (PVWF) multimers to bind platelets. Here, we showed that a pathological level of high shear stress exposure of PVWF multimers results in domain conformational changes, and the subsequent shifts in the unfolding force allow us to use force as a marker to track the dynamic states of the multimeric VWF. We found that shear-activated PVWF multimers are more resistant to mechanical unfolding than nonsheared PVWF multimers, as indicated in the higher peak unfolding force. These results provide insight into the mechanism of shear-induced activation of PVWF multimers

Strain-induced metal-semiconductor transition observed in atomic carbon chains

Carbyne, the sp(1)-hybridized phase of carbon, is still a missing link in the family of carbon allotropes. While the bulk phases of carbyne remain elusive, the elementary constituents, that is, linear chains of carbon atoms, have already been observed using the electron microscope. Isolated atomic chains are highly interesting one-dimensional conductors that have stimulated considerable theoretical work. Experimental information, however, is still very limited. Here we show electrical measurements and first-principles transport calculations on monoatomic carbon chains. When the 1D system is under strain, the chains are semi-conducting corresponding to the polyyne structure with alternating bond lengths. Conversely, when the chain is unstrained, the ohmic behaviour of metallic cumulene with uniform bond lengths is observed. This confirms the recent prediction of a metal-insulator transition that is induced by strain. The key role of the contacting leads explains the rectifying behaviour measured in monoatomic carbon chains in a nonsymmetric contact configuration

Strain- and Adsorption-Dependent Electronic States and Transport or Localization in Graphene

The chapter generalizes results on influence of uniaxial strain and adsorption on the electron states and charge transport or localization in graphene with different configurations of imperfections (point defects): resonant (neutral) adsorbed atoms either oxygen- or hydrogen-containing molecules or functional groups, vacancies or substitutional atoms, charged impurity atoms or molecules, and distortions. To observe electronic properties of graphene-admolecules system, we applied electron paramagnetic resonance technique in a broad temperature range for graphene oxides as a good basis for understanding the electrotransport properties of other active carbons. Applied technique allowed observation of possible metal-insulator transition and sorption pumping effect as well as discussion of results in relation to the granular metal model. The electronic and transport properties are calculated within the framework of the tight-binding model along with the Kubo-Greenwood quantum-mechanical formalism. Depending on electron density and type of the sites, the conductivity for correlated and ordered adsorbates is found to be enhanced in dozens of times as compared to the cases of their random distribution. In case of the uniaxially strained graphene, the presence of point defects counteracts against or contributes to the band-gap opening according to their configurations. The band-gap behaviour is found to be nonmonotonic with strain in case of a simultaneous action of defect ordering and zigzag deformation. The amount of localized charge carriers (spins) is found to be correlated with the content of adsorbed centres responsible for the formation of potential barriers and, in turn, for the localization effects. Physical and chemical states of graphene edges, especially at a uniaxial strain along one of them, play a crucial role in electrical transport phenomena in graphene-based materials.Comment: 16 pages, 10 figure

Alpha band prefrontal asymmetry does not underlie pain approach-avoidance: Results from two EEG studies

Pain research is often focused on escape from pain or approach of relief, yet individuals with chronic pain make complex choices to face their pain to satiate other drives (approach-avoidance conflicts). An abundance of research has indicated that prefrontal alpha band asymmetry (PFA) underlies approach-avoidance in general, but there is limited information about whether PFA underlies pain approach-avoidance conflicts. Electroencephalogram activity was recorded while 70 participants with chronic pain (n=33) and without chronic pain (n=37) approached/avoided stimuli containing simultaneous pain (low-high) and monetary reward (low-high). Findings from both studies revealed that approach-avoidance for pain stimuli is not accompanied by prefrontal asymmetry, irrespective of the presence of chronic pain

Mechanical and Electronic Properties of MoS2_2 Nanoribbons and Their Defects

We present our study on atomic, electronic, magnetic and phonon properties of one dimensional honeycomb structure of molybdenum disulfide (MoS$_2$) using first-principles plane wave method. Calculated phonon frequencies of bare armchair nanoribbon reveal the fourth acoustic branch and indicate the stability. Force constant and in-plane stiffness calculated in the harmonic elastic deformation range signify that the MoS$_2$ nanoribbons are stiff quasi one dimensional structures, but not as strong as graphene and BN nanoribbons. Bare MoS$_2$ armchair nanoribbons are nonmagnetic, direct band gap semiconductors. Bare zigzag MoS$_2$ nanoribbons become half-metallic as a result of the (2x1) reconstruction of edge atoms and are semiconductor for minority spins, but metallic for the majority spins. Their magnetic moments and spin-polarizations at the Fermi level are reduced as a result of the passivation of edge atoms by hydrogen. The functionalization of MoS$_2$ nanoribbons by adatom adsorption and vacancy defect creation are also studied. The nonmagnetic armchair nanoribbons attain net magnetic moment depending on where the foreign atoms are adsorbed and what kind of vacancy defect is created. The magnetization of zigzag nanoribbons due to the edge states is suppressed in the presence of vacancy defects.Comment: 11 pages, 5 figures, first submitted at November 23th, 200

Trends in health complaints from 2002 to 2010 in 34 countries and their association with health behaviours and social context factors at individual and macro-level

Publisher Copyright: © 2015 The Author. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.Background: This article describes trends and stability over time in health complaints in adolescents from 2002 to 2010 and investigates associations between health complaints, behavioural and social contextual factors at individual level and economic factors at macro-level. Methods: Comprising N = 510 876 11-, 13- and 15-year-old children and adolescents in Europe, North America and Israel, data came from three survey cycles of the international Health Behaviour in School-aged Children (HBSC) study. Age- and gender-adjusted trends in health complaints were examined in each country by means of linear regression. By using the country as the random effects variable, we tested to what extent individual and contextual variables were associated with health complaints. Results: Significant associations are stronger for individual level determinants (e.g. being bullied, smoking) than for determinants at macro-level (e.g. GDP, Gini), as can be seen by the small effect sizes (less than 5% for different trends). Health complaints are fairly stable over time in most countries, and no clear international trend in health complaints can be observed between 2002 and 2010. The most prominent stable determinants were being female, being bullied, school pressure and smoking. Conclusion: Factors associated with health complaints are more related to the proximal environment than to distal macro-level factors. This points towards intensifying targeted interventions, (e.g. for bullying) and also targeting specific risk groups. The comparably small effect size at country-level indicates that country-level factors have an impact on health and should not be ignored.publishersversionPeer reviewe