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81.
Punishers can benefit from a tough reputation, where future partners cooperate because they fear repercussions. Alternatively, punishers might receive help from bystanders if their act is perceived as just and other‐regarding. Third‐party punishment of selfish individuals arguably fits these conditions, but it is not known whether third‐party punishers are rewarded for their investments. Here, we show that third‐party punishers are indeed rewarded by uninvolved bystanders. Third parties were presented with the outcome of a dictator game in which the dictator was either selfish or fair and were allocated to one of three treatments in which they could choose to do nothing or (1) punish the dictator, (2) help the receiver, or (3) choose between punishment and helping, respectively. A fourth player (bystander) then sees the third‐party's decision and could choose to reward the third party or not. Third parties that punished selfish dictators were more likely to be rewarded by bystanders than third parties that took no action in response to a selfish dictator. However, helpful third parties were rewarded even more than third‐party punishers. These results suggest that punishment could in principle evolve via indirect reciprocity, but also provide insights into why individuals typically prefer to invest in positive actions.  相似文献   
82.

Background

Approximately 75% of children with cleft palate (CP) have Otitis Media with Effusion (OME) histories. Evidence for the effective management of OME in these children is lacking. The inconsistency in outcome measurement in previous studies has led to a call for the development of a Core Outcome Set (COS). Despite the increase in the number of published COS, involvement of patients in the COS development process, and methods to integrate the views of patients and health professionals, to date have been limited.

Methods and Findings

A list of outcomes measured in previous research was identified through reviewing the literature. Opinion on the importance of each of these outcomes was then sought from key stakeholders: Ear, Nose and Throat (ENT) surgeons, audiologists, cleft surgeons, speech and language therapists, specialist cleft nurses, psychologists, parents and children. The opinion of health professionals was sought in a three round Delphi survey where participants were asked to score each outcome using a bespoke online system. Parents and children were also asked to score outcomes in a survey and provided an in-depth insight into having OME through semi-structured interviews. The results of the Delphi survey, interviews and parent/patient survey were brought together in a final consensus meeting with representation from all stakeholders. A final set of eleven outcomes reached the definition of “consensus in” to form the recommended COS: hearing; chronic otitis media (COM); OME; receptive language skills; speech development; psycho social development; acute otitis media (AOM); cholesteatoma; side effects of treatment; listening skills; otalgia.

Conclusions

We have produced a recommendation about the outcomes that should be measured, as a minimum, in studies of the management of OME in children with CP. The development process included input from key stakeholders and used novel methodology to integrate the opinion of healthcare professionals, parents and children.  相似文献   
83.
How much should an individual invest in immunity as it grows older? Immunity is costly and its value is likely to change across an organism's lifespan. A limited number of studies have focused on how personal immune investment changes with age in insects, but we do not know how social immunity, immune responses that protect kin, changes across lifespan, or how resources are divided between these two arms of the immune response. In this study, both personal and social immune functions are considered in the burying beetle, Nicrophorus vespilloides. We show that personal immune function declines (phenoloxidase levels) or is maintained (defensin expression) across lifespan in nonbreeding beetles but is maintained (phenoloxidase levels) or even upregulated (defensin expression) in breeding individuals. In contrast, social immunity increases in breeding burying beetles up to middle age, before decreasing in old age. Social immunity is not affected by a wounding challenge across lifespan, whereas personal immunity, through PO, is upregulated following wounding to a similar extent across lifespan. Personal immune function may be prioritized in younger individuals in order to ensure survival until reproductive maturity. If not breeding, this may then drop off in later life as state declines. As burying beetles are ephemeral breeders, breeding opportunities in later life may be rare. When allowed to breed, beetles may therefore invest heavily in “staying alive” in order to complete what could potentially be their final reproductive opportunity. As parental care is important for the survival and growth of offspring in this genus, staying alive to provide care behaviors will clearly have fitness payoffs. This study shows that all immune traits do not senesce at the same rate. In fact, the patterns observed depend upon the immune traits measured and the breeding status of the individual.  相似文献   
84.
Declines or mid-elevation peaks in invertebrate diversity with elevation are often attributed to climate and geometric constraints. However, vegetation structure may also drive diversity patterns, especially for tree-dwelling species, via its effects on microhabitat use and competitive interactions. Here we investigate these effects on the diversity and community structure of tree-nesting ants over elevation. We exhaustively sampled ant nests in 1254 trees within continuous plots of primary rainforest at low (200 m a.s.l.), mid (900 m a.s.l.) and high (1800 m a.s.l.) elevation in Papua New Guinea. Ant diversity, nest abundance and tree occupancy peaked at mid-elevation. Although host tree diversity also peaked at mid-elevation, there was low specialisation of ant species to tree species at all elevations. Mid-elevation trees hosted more species, more nests and a greater diversity of nest types than trees of a similar size at low or high elevation. Tree size and nest microhabitat use were the strongest predictors of species composition, explaining twice as much of the variability in the communities than elevation. At mid to high elevation there were proportionally fewer large nests than in the lowlands, with an increase in smaller nests in live hollow twigs and epiphytes. There was high species turnover between elevations, and between trees within elevations. Species co-occurrence patterns within trees differed with tree size, and with elevation. In large trees species tended to co-occur at random at low and high elevation, but co-occurred more often than expected by chance at mid elevation, indicating an elevational shift in competitive interactions. We conclude that the more extreme diurnal temperatures at higher elevations, combined with increased epiphyte availability, drive ants to nest in more insulated microhabitats. This results in smaller colony sizes and a decrease in interspecific competition, thereby boosting species co-existence at mid elevation.  相似文献   
85.
While competition for limited breeding positions is a common feature of group life, species vary widely in the extent to which reproduction is shared among females (‘reproductive skew’). In recent years, there has been considerable debate over the mechanisms that generate variation in reproductive skew, with most evidence suggesting that subordinates breed when dominants are unable to prevent them from doing so. Here, we suggest that viviparity reduces the ability of dominant females to control subordinate reproduction and that, as a result, dominant female birds are more able than their mammal counterparts to prevent subordinates from breeding. Empirical data support this assertion. This perspective may increase our understanding of how cooperative groups form and are stabilized in nature.  相似文献   
86.
This study follows UK Afghan migrants on a return visit to Northwest Pakistan. Combining theorizations of mobility, liminality, and commensality, it takes the picnic trip (chakar) as a little‐explored cultural lens through which to analyse symbolic formations of freedom, the shaping of Pakhtun transnational labour, and social hierarchies constituted through migration and return. As potent imaginary sites of remembering and forgetting, chakar map destinations left and not‐yet arrived at, routes of flight and return, and the burden of multi‐levelled constellations of political and economic insecurity on refugees living between the UK and Pakistan. The article argues that chakar are at once therapeutic and reproductive of ways in which personal and systemic realities combine features of hierarchy, exploitation, and patriarchy. They sustain participants in a tension between desires to preserve the hierarchies they conceal, and desires for more freedom. These contradictory experiences are usefully analysed through the emblematic arc of the ‘round trip’.  相似文献   
87.

Background

Determining the presence and extent of co-morbidities is fundamental in assessing patients with chronic respiratory disease, where increased cardiovascular risk, presence of osteoporosis and low muscle mass have been recognised in several disease states. We hypothesised that the systemic consequences are evident in a further group of subjects with COPD due to Alpha-1 Antitrypsin Deficiency (A1ATD), yet are currently under-recognised.

Methods

We studied 19 patients with PiZZ A1ATD COPD and 20 age, sex and smoking matched controls, all subjects free from known cardiovascular disease. They underwent spirometry, haemodynamic measurements including aortic pulse wave velocity (aPWV), an independent predictor or cardiovascular risk, dual energy X-ray absorptiometry to determine body composition and bone mineral density.

Results

The aPWV was greater in patients: 9.9(2.1) m/s than controls: 8.5(1.6) m/s, p = 0.03, despite similar mean arterial pressure (MAP). The strongest predictors of aPWV were age, FEV1% predicted and MAP (all p < 0.01). Osteoporosis was present in 8/19 patients (2/20 controls) and was previously unsuspected in 7 patients. The fat free mass and bone mineral density were lower in patients than controls (p < 0.001).

Conclusions

Patients with A1ATD related COPD have increased aortic stiffness suggesting increased risk of cardiovascular disease and evidence of occult musculoskeletal changes, all likely to contribute hugely to overall morbidity and mortality.  相似文献   
88.
1.  Behavioural synchrony typically involves trade-offs. In the context of foraging, for example, synchrony may be suboptimal when individuals have different energy requirements but yield net benefits in terms of increased foraging success or decreased predation risk.
2.  Behavioural synchrony may also be advantageous when individuals collaborate to achieve a common goal, such as raising young. For example, in several bird species, provisioners synchronize nest-feeding visits. However, despite the apparent prevalence of provisioning synchrony, it is not known whether it is adaptive or what its function might be.
3.  Here, we propose a novel explanation for provisioning synchrony: it increases brood survival by decreasing the number of temporally separate nest visits and accordingly the chance that the nest will be detected by predators. Using cooperatively breeding pied babblers, we showed experimentally that provisioners synchronized nest visits by waiting for another provisioner before returning to the nest. Brood survival increased with provisioning synchrony. Provisioners were more likely to synchronize feeding visits for older nestlings as they were louder and possibly more conspicuous to predators. Finally, provisioners in large groups were more likely to wait for other provisioners and synchronized a higher proportion of all visits than those in smaller groups. Thus, provisioning synchrony may be one mechanism by which large groups increase brood survival in this species.
4.  This study highlights a novel strategy that birds use to increase the survival of young and demonstrates the advantages of coordinated behaviour in social species.  相似文献   
89.
Rockliffe N  Gawler D 《FEBS letters》2006,580(3):831-838
One prime candidate linking N-methyl-D-aspartate (NMDA) receptors to the regulation of the MAP kinase cascade is SynGAP, a negative regulator of Ras. In order to assess how a physiological stimulus can alter SynGAP activity, an appropriate whole cell system must be used and SynGAP must be specifically extracted from membranes whilst preserving the catalytic activity of the protein. Here, we have achieved this and studied the effect of NMDA/alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) and kainate receptor stimulations on SynGAP activity in cortical neurones. Furthermore, we have examined the role of extracellular Ca2+, CaM kinase II and the PSD-95-NR2B subunit interaction in SynGAP activity regulation and propose a novel convergence of signalling between AMPA, kainate and NMDA receptors.  相似文献   
90.
Interactions between guanidinium cations and the sulfonate groups on the phosphine [PPh2C6H4-m-SO3] have been exploited to incorporate iridium(I) centres into hydrogen-bonded networks. The crystal structure of [C(NH2)3]2{trans-[IrCl(CO)(PPh2C6H4-m-SO3)2]} (4) contains hexagonal guanidinium sulfonate (GS) sheets in which both of the sulfonate groups from each complex anion form hydrogen bonds within the same sheet. The crystal structures of [C(NH2)2(NHMe)][PPh2C6H4-m-SO3] (5) and [C(NH2)2(NHEt)][PPh2C6H4-m-SO3] (6) reveal that the GS sheets can tolerate the loss of one hydrogen bond donor, though twisting occurs to accommodate the alkyl group. However, the crystal structure of [C(NH2)2(NMe2)][PPh2C6H4-m-SO3] (7) shows that ribbon structures are formed instead of sheets when two hydrogen bond donors are lost. The compound [C(NH2)2(NHMe)]2{trans-[IrCl(CO)(PPh2C6H4-m-SO3)2]} · 3/8H2O (8) contains hydrogen-bonded cylinders as opposed to sheets. This is a likely consequence of a mismatch between the intramolecular S?S distance present in the anion, and the closer S?S distance present in a twisted GS sheet such as that in 5. The crystal structures of [C(NH2)2(NHEt)][P(O)Ph2C6H4-m-SO3] (9) and [C(NH2)2(NMe2)][P(O)Ph2C6H4-m-SO3] · H2O (10) show that the phosphine oxide group successfully competes with the sulfonate as a hydrogen bond acceptor. The crystal structure of 9 contains hydrogen-bonded ribbons that are interlinked through the anions which act as pillars to form a layer structure. In contrast, the crystal structure of 10 contains hydrogen-bonded sheets that involve cations, sulfonate groups, phosphine oxides and the included water molecule. These sheets are linked into a three-dimensional network through the anion pillars.  相似文献   
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