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Acta Biotheoretica - Both physiological and evolutionary criteria of biological individuality are underpinned by the idea that an individual is a functionally integrated whole. However, a precise... 相似文献
63.
Carolina Torres Mariana Mimosa Leonardo Galetto 《Plant Systematics and Evolution》2013,299(8):1433-1441
Plant–pollinator interactions provide highly important ecological functions, and are influenced by floral nectar characteristics. The night blooming Datura ferox is an excellent model to test general hypotheses on the relationship between nectar traits (e.g., nectar secretion patterns, nectar chemical composition), pollinators and reproductive success for invasive, weedy species in highly modified ecosystems as crop fields. We hypothesized an adjustment between nectar composition and secretion dynamics through flower anthesis and the activity and requirements of nocturnal pollinators. Nectar chemical analyses showed low quantities of amino acids and lipids, phenolics, and alkaloids were not detected. D. ferox showed sucrose-dominant nectar with comparable amount of hexoses. Sugar proportions did not vary between populations or during flowering season. Most nectar is secreted before flower opening. Nectar resorption was detected at the end of anthesis. Experimentally drained flowers of both populations increased nectar production up to 50 % in the total amount of sugar per flower compared to control flowers. Nectar standing crop was relatively constant during the flowering season, but differences were detected between populations. Nectar traits of D. ferox would be favoring cross-pollination and maintaining seed production of this weed, since recently open flowers display a higher amount of nectar and they can renew nectar after a pollinator visit or reabsorb it at the end of anthesis. This nectar source may be important for native pollinators considering that human-induced forest fragmentation is related with the impoverishment of native flora from agro-ecosystems. 相似文献
64.
Keller Ricardo Ferreira Sobrinho Ana Carolina Monteiro Santini Carlos Leonardo Sacomani Marques Maicon Gonçalves Gabriel Eduardo de Moura Neto Luciane Aparecida Pascucci Sande de Souza 《Somatosensory & motor research》2013,30(3-4):199-203
AbstractBackground: Unilateral spatial neglect (USN) is the prevalent feature in patients with right-sided stroke. It is diagnosed through the behavior inattention test (BIT) and has a negative impact on patients affecting both their functional capacity and quality of life.Objective: Here, we aimed to evaluate the impact of USN on the quality of life of patients in the chronic phase of stroke.Methods: This is a cross-sectional study with stroke patients with USN. After confirming the presence of stroke through neuroimaging examinations and of USN through the BIT, patients’ quality of life was evaluated by using the EUROQOL scale. Spearman’s correlation was used to validate the correlation between patients’ USN and quality of life, with a p?<?.05 representing significant results.Results: Eighteen individuals were included. When correlating the value of each domain of the EUROQOL scale with the results of the BIT, we observed a negative correlation between mobility (r?=?–0.97; p?=?.000), self-care (r?=?–0.82; p?=?.013), usual activities (r?=?–0.87; p?=?.005); pain or discomfort (r?=?–0.88; p?=?.004), anxiety or depression (r?=?–0.97; p?=?.000), and EUROQOL total score (r?=?–0.97, p?=?.000).Conclusion: After a correlation between the overall EUROQOL and BIT scores, we suggest that the higher the USN degree is in stroke patients, the worse their perceived quality of life tends to be. 相似文献
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Sergio A. Coelho-Souza Marcio R. Miranda Leonardo T. Salgado Ricardo Coutinho Jean R. D. Guimaraes 《Microbial ecology》2013,65(2):424-436
The ecological interaction between microorganisms and seaweeds depends on the production of secondary compounds that can influence microbial diversity in the water column and the composition of reef environments. We adapted the 3H-leucine incorporation technique to measure bacterial activity in biofilms associated with the blades of the macroalgae Sargassum spp. We evaluated (1) if the epiphytic bacteria on the blades were more active in detritus or in the biofilm, (2) substrate saturation and linearity of 3H-leucine incorporation, (3) the influence of specific metabolic inhibitors during 3H-leucine incorporation under the presence or absence of natural and artificial light, and (4) the efficiency of radiolabeled protein extraction. Scanning electron microscopy showed heterogeneous distribution of bacteria, diatoms, and polymeric extracellular secretions. Active bacteria were present in both biofilm and detritus on the blades. The highest 3H-leucine incorporation was obtained when incubating blades not colonized by macroepibionts. Incubations done under field conditions reported higher 3H-leucine incorporation than in the laboratory. Light quality and sampling manipulation seemed to be the main factors behind this difference. The use of specific metabolic inhibitors confirmed that bacteria are the main group incorporating 3H-leucine but their association with primary production suggested a symbiotic relationship between bacteria, diatoms, and the seaweed. 相似文献
68.
Sabrina Sacconi Richard J.L.F. Lemmers Judit Balog Patrick J. van der Vliet Pauline Lahaut Merlijn P. van Nieuwenhuizen Kirsten R. Straasheijm Rashmie D. Debipersad Marianne Vos-Versteeg Leonardo Salviati Alberto Casarin Elena Pegoraro Rabi Tawil Egbert Bakker Stephen J. Tapscott Claude Desnuelle Silvère M. van der Maarel 《American journal of human genetics》2013
69.
Sabrina Sacconi Richard?J.L.F. Lemmers Judit Balog Patrick?J. van?der?Vliet Pauline Lahaut Merlijn?P. van?Nieuwenhuizen Kirsten?R. Straasheijm Rashmie?D. Debipersad Marianne Vos-Versteeg Leonardo Salviati Alberto Casarin Elena Pegoraro Rabi Tawil Egbert Bakker Stephen?J. Tapscott Claude Desnuelle Silvère?M. van?der?Maarel 《American journal of human genetics》2013,93(4):744-751
Facioscapulohumeral muscular dystrophy type 1 (FSHD1) is caused by contraction of the D4Z4 repeat array on chromosome 4 to a size of 1–10 units. The residual number of D4Z4 units inversely correlates with clinical severity, but significant clinical variability exists. Each unit contains a copy of the DUX4 retrogene. Repeat contractions are associated with changes in D4Z4 chromatin structure that increase the likelihood of DUX4 expression in skeletal muscle, but only when the repeat resides in a genetic background that contains a DUX4 polyadenylation signal. Mutations in the structural maintenance of chromosomes flexible hinge domain containing 1 (SMCHD1) gene, encoding a chromatin modifier of D4Z4, also result in the increased likelihood of DUX4 expression in individuals with a rare form of FSHD (FSHD2). Because SMCHD1 directly binds to D4Z4 and suppresses somatic expression of DUX4, we hypothesized that SMCHD1 may act as a genetic modifier in FSHD1. We describe three unrelated individuals with FSHD1 presenting an unusual high clinical severity based on their upper-sized FSHD1 repeat array of nine units. Each of these individuals also carries a mutation in the SMCHD1 gene. Familial carriers of the FSHD1 allele without the SMCHD1 mutation were only mildly affected, suggesting a modifier effect of the SMCHD1 mutation. Knocking down SMCHD1 in FSHD1 myotubes increased DUX4 expression, lending molecular support to a modifier role for SMCHD1 in FSHD1. We conclude that FSHD1 and FSHD2 share a common pathophysiological pathway in which the FSHD2 gene can act as modifier for disease severity in families affected by FSHD1. 相似文献
70.
Marzia Boi Juan Antonio Llorens Lucas Cortés Gregorio Lladó Leonardo Llorens 《Grana》2013,52(2):93-105
Measurements and observations of pollen grains of varying structure before and after dehiscence of the anther sac illustrate large magnitudes of harmomegathic changes in volume and shape. Such changes are compared for colpate, porate, and colporate grains, and it is suggested that the nature of the harmomegathal action may serve to distinguish colpi or furrows from pores. Consideration of the requirement to allow harmomegathy while preventing wall collapse may provide at least partial explanation for evolution of the internal structure and external sculpturing of pollen grain walls. 相似文献