For species in which mating is resource-independent and offspring do not receive parental care, theoretical models of age-based female mate preference predict that females should prefer to mate with older males as they have demonstrated ability to survive. Thus, females should obtain a fitness benefit from mating with older males. However, male aging is often associated with reductions in quantity of sperm. The adaptive significance of age-based mate choice is therefore unclear. Various hypotheses have made conflicting predictions concerning this issue, because published studies have not investigated the effect of age on accessory gland proteins and sperm traits. D. melanogaster exhibits resource-independent mating, and offspring do not receive parental care, making this an appropriate model for studying age-based mate choice. In the present study, we found that D. melanogaster females of all ages preferred to mate with the younger of two competing males. Young males performed significantly greater courtship attempts and females showed least rejection for the same than middle-aged and old males. Young males had small accessory glands that contained very few main cells that were larger than average. Nevertheless, compared with middle-aged or old males, the young males transferred greater quantities of accessory gland proteins and sperm to mated females. As a result, females that mated with young male produced more eggs and progeny than those that mated with older males. Furthermore, mating with young male reduced female's lifespan. These studies indicate that quantity of accessory gland proteins and sperm traits decreased with male age and females obtain direct fitness benefit from mating with preferred young males.
PCR amplification and direct sequencing of regions of the cytochrome b mitochondrial genes was carried out on Iranian populations of the salmo trutta fario species. Samples of salmo trutta fario were also examined and used as an out group in the phylogenetic analysis. Results based on 1192 bp indicated differentiation between fario morphs from Iran and other salmonids also Iran and other country had collected. Despite the large phenotypic differences within salmonids, very low genetic variation was found. On the basis of the cytochrome b sequences studied, Salmo carpio and Salmo fibreni, which have been described as good species, there were high homology between salmo trutta fario , salmo trutta and salmo trutta caspius (99%), but regards salmo salar the rate of homology 93%. Regards salmo trutta fario, in hatchery trout has not red colour strips time of hatchery in salmo trutta fario whereas has a bluish grey body colour, However, they are larger than Atlantic salmon, salmo trutta caspius and salmo trutta, more regular in shape, and less intensively pigmented, moreover there are red spots are always observed in populations, however, the shape and size of salmo trutta fario is different with salmo trutta caspius and salmo trutta but the among of homology were high (99%). The salmo trutta fario and salmo trutta caspius are living in the Rivers of North of Iran that connected to Caspian Sea; perhaps these species with themselves has been conjugated, and regards salmo salar is living in the Atlantic Ocean and other Sea and Rivers connected to it, that so far to salmo trutta fario populations in Iran. However we cannot report exactly that how much homology between sequences, because already there are not complete sequence in GeneBank regards salmo trutta caspius and salmo trutta fario.
The cytochrome b gene in the salmo trutta fario has been sequenced and characterized and deposited in GeneBank, Accession Number (JN995186), the gene of cytochrome b approximately 1.2 kb. and consists of one exon from first to end of the gene, as found for all of salmonids including, salmo salar, salmo trutta caspius, salmo trutta fario that reported in GeneBank. There were the first to end of gene repetitive regions C-G that was unique for cytochrome b gene. At this study DNA extracted from muscles of salmo trutta fario, after running PCR on the gel, the PCR products purify and sequenced. The fragments aligned with BLAST Network system, the results are shown there were high homology between solmonids, the rate of homology between salmo salar 93%, salmo trutta caspius almost 95% and salmo fario (was reported in GeneBank) 93%. However, the homology of sequences were very high, but the shape of salmo trutta fario and other salmonids different, salmo trutta fario has red to purple color dots on the skin but regards salmo salar and salmo trutta caspius have grey to black dots colors on the skin.
Many studies found that the temperature has affected the fecundity and fertility in the female of Drosophila melanogaster. In this study we used male of 2-3 days age old and female of 5-6 days age old for studies of temperatures on the male reproductive performance and female fitness traits. In related to be compared three temperatures from low (15°c) temperature middle temperature (22°c) and high temperature (29°c), results were analysed by SPSS software for getting mean value , ANOVA variation and correlation relationship. In this regard, females which exposure to high temperature, among of egg laid and offspring produce (fecundity and fertility, respectively) less than middle and low temperature, that these results were significant, p value <0.000, between male and female with temperature and also between fecundity and fertility. The results of correlation relationship are shown; there was a significant Pearson correlation between three temperatures (low, middle and high) with the rate of egg laid and egg hatchability.
Objective: To evaluate the application of Ag–Cu NPs as quorum sensing (QS) inhibitors and attenuate virulence expression to overcome the global crisis of multidrug-resistant (MDR) P. aeruginosa. Methods: Ag–Cu NPs were synthesized by co-reduction of silver-nitrate and copper-nitrate (Ag:Cu = 1:1 0.75 μM). In this cross-sectional study, a total of eighty clinical strains of P. aeruginosa were collected from patients with burns. The antibacterial and resistance pattern of the clinical isolated was determined using the microdilution and Kirby Bauer disk methods. The effect of sub-MIC of Ag–Cu NPs on the expression of lasI, exoS and toxA in five clinical isolates of imipenem-resistant P. aeruginosa was performed using qRT-PCR. Results: The characterization methods confirm the formation of the Ag–Cu alloy NPs with agglomerated spherical morphology and particle sizes of about 30–40 nm. We observed that the MIC and MBC of Ag–Cu alloy NPs against MDR P. aeruginosa was found to be 2.5 and 5 μg ml−1, respectively. The effects of a sub-inhibitory concentration of Ag–Cu NPs on MDR P. aeruginosa QS and virulence-related genes showed that the expression level of QS regulatory and virulence genes significantly decreased in both MDR P. aeruginosa and reference strain under Ag–Cu sub-MIC treatment. Conclusion: Ag–Cu NPs could be potentially used as a promising QS inhibitor and anti-virulence compound against P. aeruginosa.
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