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C4 photosynthesis is thought to have evolved via intermediate stages, with changes towards the C4 phenotype gradually enhancing photosynthetic performance. This hypothesis is widely supported by modelling studies, but experimental tests are missing. Mixing of C4 components to generate artificial intermediates can be achieved via crossing, and the grass Alloteropsis semialata represents an outstanding system since it includes C4 and non-C4 populations. Here, we analyse F1 hybrids between C3 and C4, and C3+C4 and C4 genotypes to determine whether the acquisition of C4 characteristics increases photosynthetic performance. The hybrids have leaf anatomical characters and C4 gene expression profiles that are largely intermediate between those of their parents. Carbon isotope ratios are similarly intermediate, which suggests that a partial C4 cycle coexists with C3 carbon fixation in the hybrids. This partial C4 phenotype is associated with C4-like photosynthetic efficiency in C3+C4 x C4, but not in C3 x C4 hybrids, which are overall less efficient than both parents. Our results support the hypothesis that the photosynthetic gains from the upregulation of C4 characteristics depend on coordinated changes in anatomy and biochemistry. The order of acquisition of C4 components is thus constrained, with C3+C4 species providing an essential step for C4 evolution.

Lateral gene transfer (LGT) occurs in a broad range of prokaryotes and eukaryotes, occasionally promoting adaptation. LGT of functional nuclear genes has been reported among some plants, but systematic studies are needed to assess the frequency and facilitators of LGT. We scanned the genomes of a diverse set of 17 grass species that span more than 50 Ma of divergence and include major crops to identify grass-to-grass protein-coding LGT. We identified LGTs in 13 species, with significant variation in the amount each received. Rhizomatous species acquired statistically more genes, probably because this growth habit boosts opportunities for transfer into the germline. In addition, the amount of LGT increases with phylogenetic relatedness, which might reflect genomic compatibility among close relatives facilitating successful transfers. However, genetic exchanges among highly divergent species indicates that transfers can occur across almost the entire family. Overall, we showed that LGT is a widespread phenomenon in grasses that has moved functional genes across the grass family into domesticated and wild species alike. Successful LGTs appear to increase with both opportunity and compatibility.

Growth rate represents a fundamental axis of life history variation. Faster growth associated with C4 photosynthesis and annual life history has evolved multiple times, and the resulting diversity in growth is typically explained via resource acquisition and allocation. However, the underlying changes in morphogenesis remain unknown. \ud \ud - We conducted a phylogenetic comparative experiment with 74 grass species, conceptualising morphogenesis as the branching and growth of repeating modules. We aimed to establish whether faster growth in C4 and annual grasses, compared with C3 and perennial grasses, came from the faster growth of individual modules or higher rates of module initiation. \ud \ud - Morphogenesis produces fast growth in different ways in grasses using C4 and C3 photosynthesis, and in annual compared with perennial species. C4 grasses grow faster than C3 species through a greater enlargement of shoot modules and quicker secondary branching of roots. However, leaf initiation is slower and there is no change in shoot branching. Conversely, faster growth in annuals than perennials is achieved through greater branching and enlargement of shoots, and possibly faster root branching. \ud \ud - The morphogenesis of fast growth depends on ecological context, with C4 grasses tending to promote resource capture under competition, and annuals enhancing branching to increase reproductive potential.

Nail-Patella syndrome (NPS) is a genetic disorder generating physical malformations and, in approximately one in three cases, ocular and renal damage. The present research aimed to deeply understand patients' subjective experience with NPS, particularly the aspects of the syndrome that affect patients' adaptation and to propose interventions that can improve genetic and psychological counseling and help patients cope with their condition. Semi-structured interviews of nine people diagnosed with NPS were analyzed using interpretative phenomenological analysis. Results highlighted attempts to look like a person without disabilities by hiding malformations and not telling the truth about symptoms' genetic origin because of patients' poor self-esteem, negative self-cognition, and social isolation experienced from childhood to adulthood. Difficulties of adaptation to physical limits and pain were also identified. The majority of participants who were not diagnosed at birth tended to consider physical symptoms as “birth malformations” without imagining other potential implications until receiving a diagnosis. Despite the diagnosis, the majority continued to minimize the potential complications by considering NPS as a “physical difference” and not adhering to medical surveillance., SCOPUS: ar.j, info:eu-repo/semantics/published

C4 photosynthesis is considered an adaptation to warm climates, where its functional benefits are greatest and C4 plants achieve their highest diversity and dominance. However, whether inherent physiological barriers impede the persistence of C4 species in cool environments remains debated. Here, we use large grass phylogenetic and geographical distribution data sets to test whether (1) temperature influences the rate of C4 origins, (2) photosynthetic types affect the rate of migration among climatic zones, and (3) C4 evolution changes the breadth of the temperature niche. Our analyses show that C4 photosynthesis in grasses originated in tropical climates, and that C3 grasses were more likely to colonise cold climates. However, migration rates among tropical and temperate climates were higher in C4 grasses. Therefore, while the origins of C4 photosynthesis were concentrated in tropical climates, its physiological benefits across a broad temperature range expanded the niche into warmer climates and enabled diversification into cooler environments.

AIM: The aim of this study was to explore the needs of spouse caregivers of persons with dementia (PWD) and then to compare them based on the PWD's age at disease onset. This data could be used to adapt support programmes to address differences between the two groups. METHOD: Thirty-eight spouse caregivers of persons with late-onset dementia and 40 spouse caregivers of persons with early-onset dementia (PEOD) agreed to participate in the study. The mean ± SD age of the PEOD was 57.6 ± 4.0 years, whereas it was 80.9 ± 5.3 years for the persons with late-onset dementia. Interviews were conducted in the spouse caregivers' homes with only the spouse caregiver. The semi-structured interviews were based on the French version of the Carers Outcome Agreement Tool. The interviews were analyzed in two steps. The first step was qualitative to identify needs. The data were thematically analyzed using QSR NVivo 10. The second step was quantitative to compare the needs depending on the PWD's age at onset. The comparison between the two groups was performed using the χ(2) test. RESULTS: The results demonstrated that the majority of needs are the same for the two groups of spouse caregivers. All caregivers need to unwind, to stimulate and pay attention to the PWD, to break the isolation, and to be more prepared and confident. However, some differences emerge, with the spouse caregivers of PEOD expressing a greater number of needs. The caregivers of PEOD seem to have a greater need to interact and maintain contacts with other people (P = 0.001), have more general care-related needs (P = 0.005), require more appropriate care structures (P = 0.037), and need greater assistance with administrative procedures (P = 0.004). CONCLUSION: To improve spouse caregivers' well-being and sense of efficiency, it would be interesting to develop a support programme with a common framework and specific modules depending on the PWD's age at disease onset.

The circumscription of Molluginaceae has changed radically in recent years, with Corbichonia being moved to Lophiocarpaceae, Limeum to Limeaceae, Macarthuria to Macarthuriaceae and all species of H ...

C4 photosynthesis is a complex trait resulting from a series of anatomical and biochemical modifications to the ancestral C3 pathway. It is thought to evolve in a stepwise manner, creating intermediates with different combinations of C4 -like components. Determining the adaptive value of these components is key to understanding how C4 photosynthesis can gradually assemble through natural selection. Here, we decompose the photosynthetic phenotypes of numerous individuals of the grass Alloteropsis semialata, the only species known to include both C3 and C4 genotypes. Analyses of δ(13) C, physiology and leaf anatomy demonstrate for the first time the existence of physiological C3 -C4 intermediate individuals in the species. Based on previous phylogenetic analyses, the C3 -C4 individuals are not hybrids between the C3 and C4 genotypes analysed, but instead belong to a distinct genetic lineage, and might have given rise to C4 descendants. C3 A. semialata, present in colder climates, likely represents a reversal from a C3 -C4 intermediate state, indicating that, unlike C4 photosynthesis, evolution of the C3 -C4 phenotype is not irreversible.

International audience; Objectives : A 20-minutes-a-day, self-help, mindfulness-based intervention was conducted for 6 weeks with a French community sample. First, the intervention effects on affective and functioning variables were evaluated. Then, a differentialapproach was used to examine improvement potentiality and the perceived benefits of mindfulness according to the participants’ baseline mindfulness competencies.Method : Participants were non-randomly assigned to a control group on the waiting list (n = 44) or a mindfulness group (n = 47). Self-report measures assessed anxiety, depression, psychological distress, mindfulness, negative self-oriented cognition, and experiential avoidance. Results : Improvements in the variables were observed for the mindfulness group but not for the control group, with effect sizes ranging between .53 and .88. Low baseline levels of mindfulness predicted greater improvement in mindfulness (r = 0.55, p < .001) than high baseline levels.Conclusions : Mindfulness practice elicited several positive outcomes regarding affective variables, highlighting emotional functioning changes.

Summary Tropical grasses fuel the majority of fires on Earth. In fire‐prone landscapes, enhanced flammability may be adaptive for grasses via the maintenance of an open canopy and an increase in spatiotemporal opportunities for recruitment and regeneration. In addition, by burning intensely but briefly, high flammability may protect resprouting buds from lethal temperatures. Despite these potential benefits of high flammability to fire‐prone grasses, variation in flammability among grass species, and how trait differences underpin this variation, remains unknown.By burning leaves and plant parts, we experimentally determined how five plant traits (biomass quantity, biomass density, biomass moisture content, leaf surface‐area‐to‐volume ratio and leaf effective heat of combustion) combined to determine the three components of flammability (ignitability, sustainability and combustibility) at the leaf and plant scales in 25 grass species of fire‐prone South African grasslands at a time of peak fire occurrence. The influence of evolutionary history on flammability was assessed based on a phylogeny built here for the study species.Grass species differed significantly in all components of flammability. Accounting for evolutionary history helped to explain patterns in leaf‐scale combustibility and sustainability. The five measured plant traits predicted components of flammability, particularly leaf ignitability and plant combustibility in which 70% and 58% of variation, respectively, could be explained by a combination of the traits. Total above‐ground biomass was a key driver of combustibility and sustainability with high biomass species burning more intensely and for longer, and producing the highest predicted fire spread rates. Moisture content was the main influence on ignitability, where species with higher moisture contents took longer to ignite and once alight burnt at a slower rate. Biomass density, leaf surface‐area‐to‐volume ratio and leaf effective heat of combustion were weaker predictors of flammability components. Synthesis. We demonstrate that grass flammability is predicted from easily measurable plant functional traits and is influenced by evolutionary history with some components showing phylogenetic signal. Grasses are not homogenous fuels to fire. Rather, species differ in functional traits that in turn demonstrably influence flammability. This diversity is consistent with the idea that flammability may be an adaptive trait for grasses of fire‐prone ecosystems.

Grasses using the C4 photosynthetic pathway dominate frequently burned savannas, where the pathway is hypothesized to be adaptive. However, independent C4 lineages also sort among different fire environments. Adaptations to fire may thus depend on evolutionary history, which could be as important as the possession of the C4 photosynthetic pathway for life in these environments. Here, using a comparative pot experiment and controlled burn, we examined C3 and C4 grasses belonging to four lineages from the same regional flora, and asked the following questions: Do lineages differ in their responses to fire, are responses consistent between photosynthetic types, and are responses related to fire frequency in natural habitats? We found that in the C4 Andropogoneae lineage, frost killed a large proportion of aboveground biomass and produced a large dry fuel load, which meant that only a small fraction of the living tissue was lost in the fire. C3 species from the Paniceae and Danthonioideae lineages generated smaller fuel loads and lost more living biomass, while species from the C4 lineage Aristida generated the smallest fuel loads and lost the most living tissue. Regrowth after the fire was more rapid and complete in the C4 Andropogoneae and C3 Paniceae, but incomplete and slower in the C3 Danthonioideae and C4 Aristida. Rapid recovery was associated with high photosynthetic rates, high specific leaf area, delayed flowering, and frequent fires in natural habitats. Results demonstrated that phylogenetic lineage was more important than photosynthetic type in determining the fire response of these grasses and that fire responses were related to the frequency that natural habitats burned.

A striking similarity has been suggested between past and future thinking in Alzheimer's Disease (AD), a similarity attributable to abnormalities in common modular cognitive functions and neuroanatomical substrates. This study extends this literature by identifying specific executive function deficits underlying past and future thinking in AD. Twenty-four participants with a clinical diagnosis of probable (mild) AD and 26 older controls generated past and future events and underwent tests of binding and the executive functions of flexibility, inhibition, and updating. AD patients showed similar autobiographical performances in past and future event generation, and so did control participants. In each group, the similarity of past and future thinking was predicted by flexibility. Furthermore, AD patients with low flexibility showed higher similarity of past and future thinking than those with high flexibility. These findings are interpreted in terms of involvement of the hippocampus and frontal lobes in future thinking. Deficits in these brain regions in AD are likely to compromise the ability to recombine episodic information into novel and flexible configurations as scenarios for the future. © 2015 Wiley Periodicals, Inc.

C4 photosynthesis is a physiological syndrome resulting from multiple anatomical and biochemical components, which function together to increase the CO2 concentration around Rubisco and reduce photorespiration. It evolved independently multiple times and C4 plants now dominate many biomes, especially in the tropics and subtropics. The C4 syndrome comes in many flavours, with numerous phenotypic realizations of C4 physiology and diverse ecological strategies. In this work, we analyse the events that happened in a C3 context and enabled C4 physiology in the descendants, those that generated the C4 physiology, and those that happened in a C4 background and opened novel ecological niches. Throughout the manuscript, we evaluate the biochemical and physiological evidence in a phylogenetic context, which demonstrates the importance of contingency in evolutionary trajectories and shows how these constrained the realized phenotype. We then discuss the physiological innovations that allowed C4 plants to escape these constraints for two important dimensions of the ecological niche--growth rates and distribution along climatic gradients. This review shows that a comprehensive understanding of C4 plant ecology can be achieved by accounting for evolutionary processes spread over millions of years, including the ancestral condition, functional convergence via independent evolutionary trajectories, and physiological diversification.

Objectives The objective of the study was to determine whether family profiles differ between patients with anorexia nervosa or drug dependence disorder. Method 25 families of patients with anorexia nervosa and 26 families of patients with drug dependence disorder responded to a battery of self-reports (Interpersonal Dependence Inventory, Family Adaptability and Cohesion Evaluation Scales, and Family Questionnaire). Results A lack of social self-confidence was observed in patients with anorexia nervosa or drug dependence disorder and their parents. Family disturbances characterized by low cohesion and emotional reliance on another person were observed in the families of patients with anorexia nervosa or drug dependence disorder. Conclusions The present study suggests that there are differing levels of severity of family disturbances among fathers, mothers, and patients in both anorexia nervosa and drug dependence disorder.

Aim Unawareness has been operationalized in terms of a discrepancy between the patient's self-reports and three main categories of standards: judgment of a relative, clinical assessment, and objective test performance. The purpose of this study was to develop a new measure of deficit unawareness based on multidimensional, isomorphic, simple tasks and to examine the relationship between this measure and neuropsychological tests. Methods Analysis was conducted on cognitive performance prediction discrepancies in a sample of Alzheimer's disease (AD) patients and a matched comparison group. Results Patients rated their cognitive functioning more highly than their performance, but their overall self-reports were lower than the overall self-reports of the comparison group. AD patients performed significantly lower than their predicted scores in all Dementia Rating Scale (DRS) domains, in contrast to comparison participants, who did not consistently perform significantly lower across domains. All unawareness scores were moderately inter-correlated, except for memory, and all unawareness scores with the exception of memory were correlated with overall neuropsychological functioning. Conclusion A methodological and conceptual difficulty has been identified, and this raises the issue of the generalizability of studies with a focus on memory unawareness. The method proposed seems a good tool to assess the relationships between unawareness and several different aspects of cognitive functioning, in particular executive functioning.

• Grasses rank among the world's most ecologically and economically important plants. Repeated evolution of the C(4) syndrome has made photosynthesis highly efficient in many grasses, inspiring intensive efforts to engineer the pathway into C(3) crops. However, comparative biology has been of limited use to this endeavor because of uncertainty in the number and phylogenetic placement of C(4) origins. • We built the most comprehensive and robust molecular phylogeny for grasses to date, expanding sampling efforts of a previous working group from 62 to 531 taxa, emphasizing the C(4)-rich PACMAD (Panicoideae, Arundinoideae, Chloridoideae, Micrairoideae, Aristidoideae and Danthonioideae) clade. Our final matrix comprises c. 5700 bp and is93% complete. • For the first time, we present strong support for relationships among all the major grass lineages. Several new C(4) lineages are identified, and previously inferred origins confirmed. C(3)/C(4) evolutionary transitions have been highly asymmetrical, with 22-24 inferred origins of the C(4) pathway and only one potential reversal. • Our backbone tree clarifies major outstanding systematic questions and highlights C(3) and C(4) sister taxa for comparative studies. Two lineages have emerged as hotbeds of C(4) evolution. Future work in these lineages will be instrumental in understanding the evolution of this complex trait.

C(4) photosynthesis is a series of biochemical and structural modifications to C(3) photosynthesis that has evolved numerous times in flowering plants, despite requiring modification of up to hundreds of genes. To study the origin of C(4) photosynthesis, we reconstructed and dated the phylogeny of Molluginaceae, and identified C(4) taxa in the family. Two C(4) species, and three clades with traits intermediate between C(3) and C(4) plants were observed in Molluginaceae. C(3)-C(4) intermediacy evolved at least twice, and in at least one lineage was maintained for several million years. Analyses of the genes for phosphoenolpyruvate carboxylase, a key C(4) enzyme, indicate two independent origins of fully developed C(4) photosynthesis in the past 10 million years, both within what was previously classified as a single species, Mollugo cerviana. The propensity of Molluginaceae to evolve C(3)-C(4) and C(4) photosynthesis is likely due to several traits that acted as developmental enablers. Enlarged bundle sheath cells predisposed some lineages for the evolution of C(3)-C(4) intermediacy and the C(4) biochemistry emerged via co-option of photorespiratory recycling in C(3)-C(4) intermediates. These evolutionarily stable transitional stages likely increased the evolvability of C(4) photosynthesis under selection environments brought on by climate and atmospheric change in recent geological time.

During the origin of agriculture in the Fertile Crescent, the broad spectrum of wild plant species exploited by hunter‐gatherers narrowed dramatically. The mechanisms responsible for this specialization and the associated domestication of plants are intensely debated. We investigated why some species were domesticated rather than others, and which traits they shared. We tested whether the progenitors of cereal and pulse crops, grown individually, produced a higher yield and less chaff than other wild grasses and legumes, thereby maximizing the return per seed planted and minimizing processing time. We compared harvest traits of species originating from the Fertile Crescent, including those for which there is archaeological evidence of deliberate collection. Unexpectedly, wild crop progenitors in both families had neither higher grain yield nor, in grasses, less chaff, although they did have larger seeds. Moreover, small‐seeded grasses actually returned a higher yield relative to the mass of seeds sown. However, cereal progenitors had threefold fewer seeds per plant, representing a major difference in how seeds are packaged on plants. These data suggest that there was no intrinsic yield advantage to adopting large‐seeded progenitor species as crops. Explaining why Neolithic agriculture was founded on these species, therefore, remains an important unresolved challenge.