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51.
Breeding synchrony and extrapair paternity in a species with alternative reproductive strategies
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Mellisa L. Grunst Andrea S. Grunst Rusty A. Gonser Elaina M. Tuttle 《Journal of avian biology》2017,48(8):1087-1094
Breeding synchrony may affect the tradeoff between pursuing multiple mates and avoiding paternity loss, translating into differences in the rate of extrapair paternity (EPP). However, diverse empirical relationships between breeding synchrony and EPP remain challenging to explain. We examined whether the relationship between breeding synchrony and EPP varied with male morph, age, body size, or breeding density in the white‐throated sparrow Zonotrichia albicollis. In this species, males of two genetically determined morphs pursue alternative mating strategies. Breeding synchrony positively correlated with EPP within polygamous white morph males, which have high rates of EPP and cuckoldry, but was unrelated to EPP within tan morph males, which prioritize mate guarding and paternal care. As previously reported, males that gained EPP were primarily white males. Males gained EPP more often than expected by chance during their mate's fertile period and on neighboring territories. Since extrapair copulation appears primarily male‐driven in this species, these results indicate that white males focus extra‐pair mating effort during periods of high synchrony and during their mates’ fertile periods, even at the expense of paternity loss within their own nests. Breeding density, male age, and male size did not modify the relationship between breeding synchrony and EPP. However, older white males had higher cuckoldry rates, perhaps reflecting declines in performance associated with senescence. Results suggest that, even within species, mating strategy may modify how breeding synchrony affects rates of EPP, with positive relationships manifest only within subsets of individuals that pursue a strategy of polygyny at the expense of paternity loss. 相似文献
52.
Célia Regina Moreira Lanza Carlos Alberto de Souza Costa Maysa Furlan Alberto Alécio Josimeri Hebling 《Cell biology and toxicology》2009,25(6):533-543
Objective
To evaluated the transdentinal diffusion and subsequent cytotoxicity of self-etching adhesives on odontoblast-like cells. 相似文献53.
Manuela Malatesta Sandra Furlan Raffaella Mariotti Carlo Zancanaro Carlo Nobile 《Histochemistry and cell biology》2009,132(5):505-513
The Lgi1 protein is involved in the pathogenesis of autosomal dominant lateral temporal epilepsy because mutations in the leucine-rich, glioma-inactivated 1 (LGI1) gene have been found in affected subjects and families; however, the function of Lgi1 is still unclear. Definition of the fine intracellular distribution of Lgi1 in normal cortical tissue would add in understanding its role and envisage pathogenetic mechanisms. Therefore, we analyzed normal rat cortex for Lgi1 by combining biochemistry, immunohistochemistry and immunoelectron microscopy. Our results demonstrate that Lgi1 is a cytoplasmic protein distributed both in the soma and in the processes of neurons: it occurs on the rough endoplasmic reticulum, the site of synthesis, in the Golgi complex, where it undergoes glycosylation, and in close proximity to neurotubules and neurofilaments, especially in the axons, but it is scarce at synapses and the neurilemma. Lgi1 association with axonal cytoskeletal structures would imply Lgi1 is either transported along axons by motor proteins, or playing some role as a carrier in the axonal flux, or it could be involved in the regulation of cytoskeletal organization. 相似文献
54.
Dana Willner Mike Furlan Matthew Haynes Robert Schmieder Florent E. Angly Joas Silva Sassan Tammadoni Bahador Nosrat Douglas Conrad Forest Rohwer 《PloS one》2009,4(10)
The human respiratory tract is constantly exposed to a wide variety of viruses, microbes and inorganic particulates from environmental air, water and food. Physical characteristics of inhaled particles and airway mucosal immunity determine which viruses and microbes will persist in the airways. Here we present the first metagenomic study of DNA viral communities in the airways of diseased and non-diseased individuals. We obtained sequences from sputum DNA viral communities in 5 individuals with cystic fibrosis (CF) and 5 individuals without the disease. Overall, diversity of viruses in the airways was low, with an average richness of 175 distinct viral genotypes. The majority of viral diversity was uncharacterized. CF phage communities were highly similar to each other, whereas Non-CF individuals had more distinct phage communities, which may reflect organisms in inhaled air. CF eukaryotic viral communities were dominated by a few viruses, including human herpesviruses and retroviruses. Functional metagenomics showed that all Non-CF viromes were similar, and that CF viromes were enriched in aromatic amino acid metabolism. The CF metagenomes occupied two different metabolic states, probably reflecting different disease states. There was one outlying CF virome which was characterized by an over-representation of Guanosine-5′-triphosphate,3′-diphosphate pyrophosphatase, an enzyme involved in the bacterial stringent response. Unique environments like the CF airway can drive functional adaptations, leading to shifts in metabolic profiles. These results have important clinical implications for CF, indicating that therapeutic measures may be more effective if used to change the respiratory environment, as opposed to shifting the taxonomic composition of resident microbiota. 相似文献
55.
Recent developments in dynamic combinatorial chemistry 总被引:1,自引:0,他引:1
Generating combinatorial libraries under equilibrium conditions has the important advantage that the libraries are adaptive (i.e. they can respond to exterior influences in the form of molecular recognition events). Thus, a ligand will direct and amplify the formation of its ideal receptor and vice versa. Proof of principle of this approach has been established using small libraries showing highly efficient amplification of selected receptors. The approach has recently been extended to address folding of macromolecules, including peptides. 相似文献
56.
57.
Factors Affecting Exocellular Polysaccharide Production by Lactobacillus delbrueckii subsp. bulgaricus Grown in a Chemically Defined Medium 总被引:1,自引:0,他引:1
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Sandrine Petry Sylviane Furlan Marie-Jeanne Crepeau Jutta Cerning Michel Desmazeaud 《Applied microbiology》2000,66(8):3427-3431
We developed a chemically defined medium (CDM) containing lactose or glucose as the carbon source that supports growth and exopolysaccharide (EPS) production of two strains of Lactobacillus delbrueckii subsp. bulgaricus. The factors found to affect EPS production in this medium were oxygen, pH, temperature, and medium constituents, such as orotic acid and the carbon source. EPS production was greatest during the stationary phase. Composition analysis of EPS isolated at different growth phases and produced under different fermentation conditions (varying carbon source or pH) revealed that the component sugars were the same. The EPS from strain L. delbrueckii subsp. bulgaricus CNRZ 1187 contained galactose and glucose, and that of strain L. delbrueckii subsp. bulgaricus CNRZ 416 contained galactose, glucose, and rhamnose. However, the relative proportions of the individual monosaccharides differed, suggesting that repeating unit structures can vary according to specific medium alterations. Under pH-controlled fermentation conditions, L. delbrueckii subsp. bulgaricus strains produced as much EPS in the CDM as in milk. Furthermore, the relative proportions of individual monosaccharides of EPS produced in pH-controlled CDM or in milk were very similar. The CDM we developed may be a useful model and an alternative to milk in studies of EPS production. 相似文献
58.
Dual inoculations onLeucaena esculenta plants of eitherGlomus versiforme andRhizobium loti NGR 8 orGlomus sp. andR. loti ENCB 31, gave higher growth and phosphorus accumulation compared with treatments with a single micro-symbiont. The above combinations could be used in a re-forestation programme withL. esculenta in the highlands of Oaxaca State, Mexico. The use of endomycorrhized plants is recommended to alleviate the planting shock-phase, particularly in arid zones, and also the risk of root colonization by possibly less-efficient indigenous fungi. 相似文献
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60.
Fifty individual psychotherapies of schizophrenic patients, supervised by a control group for fourteen years, are examined. 80 percent of the patients have shown important clinical progress and, in many cases, have been healed, especially those who continued therapy for more than two years and who had a deep and reciprocal emotional involvement with the therapist during and after treatment; there was a reduction by 70 percent of hospitalizations during this treatment and only one of these had a relapse. Other data confirm the efficacy of psychotherapy; however, to give a new instrument of scientific confirmation to this type of individual and subjective work, we tried to observe how the psychopathological and therapeutic mechanism of "symbiosis" induces personal dynamics in the therapist which are reflected in the control group. The psychopathological symbiotic disturbance of the patient, the therapeutic symbiotic relationship, and the way in which the group reacts to these permit the creation of a useful triangle, both for the therapist to understand his position toward the patient and to confirm or correct the subjective aspects of such a deep and emotional relationship. 相似文献