Leaders can launch hostile attacks on out-groups and organize in-group defence. Whether groups settle the confict in their favour depends, however, on whether followers align with leader’s... Show moreLeaders can launch hostile attacks on out-groups and organize in-group defence. Whether groups settle the confict in their favour depends, however, on whether followers align with leader’s initiatives. Yet how leader and followers coordinate during intergroup confict remains unknown. Participants in small groups elected a leader and made costly contributions to intergroup confict while dorsolateral prefrontal cortex (DLPFC) activity was simultaneously measured. Leaders were more sacrifcial and their contribution infuenced group survival to a greater extent during in-group defence than during out-group attacks. Leaders also had increased DLPFC activity when defending in-group, which predicted their comparatively strong contribution to confict; followers reciprocated their leader’s initiatives the more their DLPFC activity synchronized with that of their leader. When launching attacks, however, leaders and followers aligned poorly at behavioural and neural levels, which explained why out-group attacks often failed. Our results provide a neurobehavioural account of leader–follower coordination during intergroup confict and reveal leader–follower behavioural/neural alignment as pivotal for groups settling conficts in their favour. Show less
Human society operates on large-scale cooperation. However, individual differences in cooperativeness and incentives to free ride on others' cooperation make large-scale cooperation fragile and can... Show moreHuman society operates on large-scale cooperation. However, individual differences in cooperativeness and incentives to free ride on others' cooperation make large-scale cooperation fragile and can lead to reduced social welfare. Thus, how individual cooperation spreads through human social networks remains puzzling from ecological, evolutionary, and societal perspectives. Here, we identify oxytocin and costly punishment as biobehavioral mechanisms that facilitate the propagation of cooperation in social networks. In three laboratory experiments (n = 870 human participants: 373 males, 497 females), individuals were embedded in heterogeneous networks and made repeated decisions with feedback in games of trust (n = 342), ultimatum bargaining (n = 324), and prisoner's dilemma with punishment (n = 204). In each heterogeneous network, individuals at central positions (hub nodes) were given intranasal oxytocin (or placebo). Giving oxytocin (vs matching placebo) to central individuals increased their trust and enforcement of cooperation norms. Oxytocin-enhanced norm enforcement, but not elevated trust, explained the spreading of cooperation throughout the social network. Moreover, grounded in evolutionary game theory, we simulated computer agents that interacted in heterogeneous networks with central nodes varying in terms of cooperation and punishment levels. Simulation results confirmed that central cooperators' willingness to punish noncooperation allowed the permeation of the network and enabled the evolution of network cooperation. These results identify an oxytocin-initiated proximate mechanism explaining how individual cooperation facilitates network-wide cooperation in human society and shed light on the widespread phenomenon of heterogeneous composition and enforcement systems at all levels of life. Show less
Research links high blood pressure variability (BPV) with stroke and cerebrovascular disease, however, its association with cognition remains unclear. Moreover, it remains uncertain which BP... Show moreResearch links high blood pressure variability (BPV) with stroke and cerebrovascular disease, however, its association with cognition remains unclear. Moreover, it remains uncertain which BP-derived parameter (ie, variability or mean) holds more significance in understanding vascular contributions to cognitive impairment. We searched PubMed, Embase, PsycINFO, and Scopus and performed a meta-analysis of studies that quantified the association between resting BPV with dementia or cognitive impairment in adults. Two authors independently reviewed all titles, abstracts, and full-texts and extracted data, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-Analysis of Observational Studies in Epidemiology guidelines. Study quality was assessed using the (modified) Newcastle-Ottawa Scale. A multilevel meta-analysis was used, which included effect sizes for both BPV and mean BP, with a combined end point of dementia or cognitive impairment as primary outcome. In the primary analysis, 54 effect sizes were extracted from 20 studies, with a total analytical sample of n=7 899 697. Higher systolic BPV (odds ratio [OR], 1.25 [95% CI, 1.16-1.35]), mean systolic pressure (OR, 1.12 [95% CI, 1.02-1.29]), diastolic BPV (OR, 1.20 [95% CI, 1.12-1.29]), and mean diastolic pressure (OR, 1.16 [95% CI, 1.04-1.29]) were associated with dementia and cognitive impairment. A direct comparison showed that mean BP effect sizes were less strong than BPV effect sizes (OR, 0.92 [95% CI, 0.87-0.97], P<0.01), indicating that the relative contribution of BPV exceeded that of mean BP. Methodological and statistical heterogeneity was high. Secondary analyses were less consistent as to whether BPV and mean BP were differentially associated with dementia subtypes and cognitive domains. Future studies are required to investigate BPV as a target for dementia prevention. Show less
Natural deep eutectic solvents (NADES) are proposed as alternative solvents for peroxygenase‐catalysed oxyfunctionalization reactions. Choline chloride‐based NADES are of particular interest as... Show moreNatural deep eutectic solvents (NADES) are proposed as alternative solvents for peroxygenase‐catalysed oxyfunctionalization reactions. Choline chloride‐based NADES are of particular interest as they can serve as solvent, enzyme‐stabiliser and sacrificial electron donor for the in situ H2O2 generation. This report provides the first proof‐of‐concept and basic characterisation of this new reaction system. Highly promising turnover numbers for the biocatalysts of up to 200,000 have been achieved. Show less
Roelands, J.; Garand, M.; Hinchcliff, E.; Ma, Y.; Shah, P.; Toufiq, M.; ... ; Chaussabel, D. 2019
The use of natural deep eutectic solvents (NADES) as multifunctional solvents for limonene bioprocessing was reported. NADES were used for the extraction of limonene from orange peel wastes, as... Show moreThe use of natural deep eutectic solvents (NADES) as multifunctional solvents for limonene bioprocessing was reported. NADES were used for the extraction of limonene from orange peel wastes, as solvent for the chemoenzymatic epoxidation of limonene, and as sacrificial electron donor for the in situ generation of H2O2 to promote the epoxidation reaction. The proof‐of‐concept for this multifunctional use was provided, and the scope and current limitations of the concept were outlined. Show less
Intergroup conflict contributes to human discrimination and violence, but persists because individuals make costly contributions to their group’s fighting capacity. Yet, how group members... Show moreIntergroup conflict contributes to human discrimination and violence, but persists because individuals make costly contributions to their group’s fighting capacity. Yet, how group members effectively coordinate their contributions during intergroup conflict remains poorly understood. Here, we examine the role of oxytocin for (the coordination of) contributions to group attack or defense in multi-round, real-time feedback intergroup contests. In a double-blind placebo-controlled study with N = 480 males in Intergroup Attacker-Defender Contests, we found that oxytocin reduced contributions to attack and over time increased attacker’s within-group coordination of contributions. However, rather than becoming peaceful, attackers given oxytocin better tracked their rival’s historical defense and coordinated their contributions into well-timed and hence more profitable attacks. Our results reveal coordination of contributions as a critical component of successful attacks and subscribe to the possibility that oxytocin enables individuals to contribute to in-group efficiency and prosperity even when doing so implies outsiders are excluded or harmed. Show less
The stable isotope ratios of carbon (d13C), nitrogen (d15N) and sulphur (d34S) are measured to examine human diet, social stratification, mobility and animal husbandry practices. Three locations... Show moreThe stable isotope ratios of carbon (d13C), nitrogen (d15N) and sulphur (d34S) are measured to examine human diet, social stratification, mobility and animal husbandry practices. Three locations comprising four sites from the Yellow River Valleys of north China are investigated: Nancheng (Hebei Province), Xishan (Gansu Province), Liyi and Shanren (Shaanxi Province), and this work represents one of the largest and most detailed isotopic research projects ever conducted in China. This thesis focused on time periods and cultures that were previously underrepresented, in the literature such as the early Bronze/Iron Ages to the Qin Dynasty (221-206 BC). Further, this thesis found new evidence concerning dietary patterns, social stratification (or lack thereof), animal husbandry practices and human mobility during these formative pre-Qin Empire periods. Show less
Liu, M.; Chen, C.C.; Chen, L.; Xiao, X.; Zheng, Y.; Huang, J.W.; ... ; Ma, Y. 2016
To identify susceptibility loci for classical Hodgkin's lymphoma (cHL), we conducted a genome-wide association study of 589 individuals with cHL (cases) and 5,199 controls with validation in four... Show moreTo identify susceptibility loci for classical Hodgkin's lymphoma (cHL), we conducted a genome-wide association study of 589 individuals with cHL (cases) and 5,199 controls with validation in four independent samples totaling 2,057 cases and 3,416 controls. We identified three new susceptibility loci at 2p16.1 (rs1432295, REL, odds ratio (OR) = 1.22, combined P = 1.91 x 10(-8)), 8q24.21 (rs2019960, PVT1, OR = 1.33, combined P = 1.26 x 10(-13)) and 10p14 (rs501764, GATA3, OR = 1.25, combined P = 7.05 x 10(-8)). Furthermore, we confirmed the role of the major histocompatibility complex in disease etiology by revealing a strong human leukocyte antigen (HLA) association (rs6903608, OR = 1.70, combined P = 2.84 x 10(-50)). These data provide new insight into the pathogenesis of cHL. Show less
Common genetic variation at human 8q23.3 is significantly associated with colorectal cancer (CRC) risk. To elucidate the basis of this association we compared the frequency of common variants at... Show moreCommon genetic variation at human 8q23.3 is significantly associated with colorectal cancer (CRC) risk. To elucidate the basis of this association we compared the frequency of common variants at 8q23.3 in 1,964 CRC cases and 2,081 healthy controls. Reporter gene studies showed that the single nucleotide polymorphism rs16888589 acts as an allele-specific transcriptional repressor. Chromosome conformation capture (3C) analysis demonstrated that the genomic region harboring rs16888589 interacts with the promoter of gene for eukaryotic translation initiation factor 3, subunit H (EIF3H). We show that increased expression of EIF3H gene increases CRC growth and invasiveness thereby providing a biological mechanism for the 8q23.3 association. These data provide evidence for a functional basis for the non-coding risk variant rs16888589 at 8q23.3 and provides novel insight into the etiological basis of CRC. Show less
Understanding the molecular mechanisms of survival and migratory pathways in cancer cells is essential to better comprehending cancer progression, metastasis formation and drug resistance, thereby... Show moreUnderstanding the molecular mechanisms of survival and migratory pathways in cancer cells is essential to better comprehending cancer progression, metastasis formation and drug resistance, thereby benefiting the development of novel anticancer treatments. The overall goal of the work is to better understand the role and mechanism of focal adhesion mediated signaling in the control of anticancer drug-related survival signaling of breast tumor cells in vivo as well as the regulation of cell migration of breast tumor cells in vitro. Mainly, we focused on the role of the focal adhesion associated proteins (focal adhesion kinase and paxillin) in cell survival, cytoskeleton reorganization and migration. Moreover, we would like to identify the pattern of C-X-C chemokines and corresponding receptors that mediate the downstream signaling events in tumor cell migration and invasion. Show less