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There are several hypotheses suggesting that social complexity, including pair bonding, is important in the evolution of increased brain size. I examined whether genetic or social monogamy was related to large brain size in birds. Recent work has indicated that the length and strength of pair bonds are associated with large brain size. I tested several hypotheses for the evolution of large brain size in 42 species of bird by including life history variables in a regression model. A test on 100 phylogenetic trees revealed no phylogenetic signal in brain size. Controlling for body size, a principal components analysis was run on the life history variables and degrees of extra‐pair paternity. The main principal component (PC1) was regressed on brain size revealing a strong, positive association. Social, but not genetic, monogamy was positively related to brain size. Large brain size is related to the selective pressures of procuring extra‐pair copulations whilst maintaining a social partnership. However, other life history variables also loaded positively and significantly on brain size. These results indicate that the evolution of large brain size in birds was driven by several important selective pressures. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 668–678.  相似文献   
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Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+‐PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high‐throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse‐grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to null segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild‐type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse‐ or field‐grown plants. This study validates our greenhouse‐based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields.  相似文献   
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The animal cell polarity regulator Par-3 recruits the Par complex (consisting of Par-6 and atypical PKC, aPKC) to specific sites on the cell membrane. Although numerous physical interactions have been reported between Par-3 and the Par complex, it is unclear how each of these interactions contributes to the overall binding. Using a purified, intact Par complex and a quantitative binding assay, here, we found that the energy required for this interaction is provided by the second and third PDZ protein interaction domains of Par-3. We show that both Par-3 PDZ domains bind to the PDZ-binding motif of aPKC in the Par complex, with additional binding energy contributed from the adjacent catalytic domain of aPKC. In addition to highlighting the role of Par-3 PDZ domain interactions with the aPKC kinase domain and PDZ-binding motif in stabilizing Par-3–Par complex assembly, our results indicate that each Par-3 molecule can potentially recruit two Par complexes to the membrane during cell polarization. These results provide new insights into the energetic determinants and structural stoichiometry of the Par-3–Par complex assembly.  相似文献   
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Continuous livestock grazing can have negative effects on biodiversity and landscape function in arid and semi‐arid rangelands. Alternative grazing management practices, such as rotational grazing, may be a viable option for broad‐scale biodiversity conservation and sustainable pastoral management. This study compared ground cover, plant species composition and floristic and functional diversity along gradients of grazing intensity between a pastoral property rotationally grazed by goats and an adjacent nature reserve (ungrazed by commercial livestock) in semi‐arid south‐eastern Australia. Understorey plant species composition differed significantly between the rotationally grazed property and the nature reserve, with a greater proportion and frequency of palatable species recorded in the nature reserve. Understorey plant species richness, diversity, functional biodiversity measures and ground cover declined with increasing grazing pressure close to water points under commercial rotational grazing management. However, at a whole‐paddock scale, there were few differences in plant biodiversity and ground cover between the rotationally grazed property and the nature reserve, despite differences in overall plant species composition. Flexible, adaptive, rotational grazing should be investigated further for its potential to achieve both socio‐economic and biodiversity conservation outcomes in semi‐arid rangelands to complement existing conservation reserves.  相似文献   
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BackgroundJoint reminiscence groups, involving people with dementia and family carers together, are popular, but the evidence-base is limited. This study aimed to assess the effectiveness and cost-effectiveness of joint reminiscence groups as compared to usual care.MethodsThis multi-centre, pragmatic randomised controlled trial had two parallel arms: intervention group and usual-care control group. A restricted dynamic method of randomisation was used, with an overall allocation ratio of 1:1, restricted to ensure viable sized intervention groups. Assessments, blind to treatment allocation, were carried out at baseline, three months and ten months (primary end-point), usually in the person''s home. Participants were recruited in eight centres, mainly through NHS Memory Clinics and NHS community mental health teams. Included participants were community resident people with mild to moderate dementia (DSM-IV), who had a relative or other care-giver in regular contact, to act as informant and willing and able to participate in intervention. 71% carers were spouses. 488 people with dementia (mean age 77.5)were randomised: 268 intervention, 220 control; 350 dyads completed the study (206 intervention, 144 control). The intervention evaluated was joint reminiscence groups (with up to 12 dyads) weekly for twelve weeks; monthly maintenance sessions for further seven months. Sessions followed a published treatment manual and were held in a variety of community settings. Two trained facilitators in each centre were supported by volunteers. Primary outcome measures were self-reported quality of life for the person with dementia (QoL-AD), psychological distress for the carer (General Health Questionnaire, GHQ-28). Secondary outcome measures included: autobiographical memory and activities of daily living for the person with dementia; carer stress for the carer; mood, relationship quality and service use and costs for both.ResultsThe intention to treat analysis (ANCOVA) identified no differences in outcome between the intervention and control conditions on primary or secondary outcomes (self-reported QoL-AD mean difference 0.07 (-1.21 to 1.35), F = 0.48, p = 0.53). Carers of people with dementia allocated to the reminiscence intervention reported a significant increase in anxiety on a General Health Questionnaire-28 sub-scale at the ten month end-point (mean difference 1.25 (0.25 to 2.26), F = 8.28, p = 0.04). Compliance analyses suggested improved autobiographical memory, quality of life and relationship quality for people with dementia attending more reminiscence sessions, however carers attending more groups showed increased care-giving stress. Economic analyses from a public sector perspective indicated that joint reminiscence groups are unlikely to be cost-effective. There were no significant adverse effects attributed to the intervention. Potential limitations of the study include less than optimal attendance at the group sessions—only 57% of participants attended at least half of the intervention sessions over the 10 month period, and a higher rate of study withdrawal in the control group.ConclusionsThis trial does not support the clinical effectiveness or cost-effectiveness of joint reminiscence groups. Possible beneficial effects for people with dementia who attend sessions as planned are offset by raised anxiety and stress in their carers. The reasons for these discrepant outcomes need to be explored further, and may necessitate reappraisal of the movement towards joint interventions.

Trial Registration

ISRCTN Registry ISRCTN42430123  相似文献   
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Background:When patients and physicians speak the same language, it may improve the quality and safety of care delivered. We sought to determine whether patient–physician language concordance is associated with in-hospital and postdischarge outcomes among home care recipients who were admitted to hospital.Methods:We conducted a population-based study of a retrospective cohort of 189 690 home care recipients who were admitted to hospital in Ontario, Canada, between 2010 and 2018. We defined patient language (obtained from home care assessments) as English (Anglophone), French (Francophone) or other (allophone). We obtained physician language from the College of Physicians and Surgeons of Ontario. We defined hospital admissions as language concordant when patients received more than 50% of their care from physicians who spoke the patients’ primary language. We identified in-hospital (adverse events, length of stay, death) and post-discharge outcomes (emergency department visits, readmissions, death within 30 days of discharge). We used regression analyses to estimate the adjusted rate of mean and the adjusted odds ratio (OR) of each outcome, stratified by patient language, to assess the impact of language-concordant care within each linguistic group.Results:Allophone patients who received language-concordant care had lower risk of adverse events (adjusted OR 0.25, 95% confidence interval [CI] 0.15–0.43) and in-hospital death (adjusted OR 0.44, 95% CI 0.29–0.66), as well as shorter stays in hospital (adjusted rate of mean 0.74, 95% CI 0.66–0.83) than allophone patients who received language-discordant care. Results were similar for Francophone patients, although the magnitude of the effect was smaller than for allophone patients. Language concordance or discordance of the hospital admission was not associated with significant differences in postdischarge outcomes.Interpretation:Patients who received most of their care from physicians who spoke the patients’ primary language had better in-hospital outcomes, suggesting that disparities across linguistic groups could be mitigated by providing patients with language-concordant care.

A growing number of people in Canada (more than 6.1 million in 2016) are faced with the challenge of living in a situation in which their primary language is not spoken by most of the population and is not recognized as an official provincial or territorial language. 1,2 We refer to this as a minority language situation, and such people include Francophones living outside of Quebec, Anglophones living in Quebec, and all residents of Canada whose primary language is a language other than English or French (allophones). Numerous studies have shown that people in North America with limited English proficiency generally have poorer access to health care and receive health care services of lower quality and safety, resulting in higher risk of adverse events and increased health resource use.38 Despite these findings, few authors have considered the impact of patient–provider language concordance, whereby patients and providers have proficiency in a shared language.9 Studies in the United States have shown that patients with asthma who receive language-concordant primary care are less likely to omit medications, miss appointments or visit the emergency department.10 Patients with diabetes who receive language-concordant care have improved glycemic and low-density-lipoprotein control,11,12 as well as increased participation in diabetic foot care programs.13 Although patient language is generally considered to be a nonmodifiable risk factor, language discordance represents a potentially modifiable variable, which could be the target of interventions (e.g., by referring patients to providers who have proficiency in their primary language).Frail patients are more likely to have communication problems and poor health outcomes than the general population; thus, language concordance may be particularly important in this patient population.14,15 The risk of harm for frail, older patients has been attributed to medical complexity and multi-morbidity; 1618 however, since communication barriers also increase with age, older patients may also be more likely to experience harm because of poor patient–provider communication. 19 Most studies of language concordance have been limited to the primary care setting. We are aware of 2 studies conducted in the acute care setting, with 1 showing that Francophones residing in Ontario were less likely to experience harm when they were treated in hospitals that were required by law to provide services French. 20,21We sought to compare the risk of adverse, hospital-related outcomes among frail patients living in Ontario, Canada, after stratifying by patient language and patient–physician language concordance or discordance. We hypothesized that patients receiving language-concordant care would have better outcomes than those receiving language-discordant care.  相似文献   
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PDZ protein interaction domains are typically selective for C-terminal ligands, but non-C-terminal, 'internal' ligands have also been identified. The PDZ domain from the cell polarity protein Par-6 binds C-terminal ligands and an internal sequence from the protein Pals1/Stardust. The structure of the Pals1-Par-6 PDZ complex reveals that the PDZ ligand-binding site is deformed to allow for internal binding. Whereas binding of the Rho GTPase Cdc42 to a CRIB domain adjacent to the Par-6 PDZ regulates binding of C-terminal ligands, the conformational change that occurs upon binding of Pals1 renders its binding independent of Cdc42. These results suggest a mechanism by which the requirement for a C terminus can be readily bypassed by PDZ ligands and reveal a complex set of cooperative and competitive interactions in Par-6 that are likely to be important for cell polarity regulation.  相似文献   
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