Abstract Within the context of a conservation program the management of subdivided populations implies a compromise between the control of the global genetic diversity, the avoidance of high inbreeding levels, and, sometimes, the maintenance of a certain degree of differentiation between subpopulations. We present a dynamic and flexible methodology, based on genealogical information, for the maximization of the genetic diversity (measured through the global population coancestry) in captive subdivided populations while controlling/restricting the levels of inbreeding. The method is able to implement specific restrictions on the desired relative levels of coancestry between and within subpopulations. By accounting for the particular genetic population structure, the method determines the optimal contributions (i.e., number of offspring) of each individual, the number of migrants, and the particular subpopulations involved in the exchange of individuals. Computer simulations are used to illustrate the procedure and its performance in a range of reasonable scenarios. The method performs well in most situations and is shown to be more efficient than the commonly accepted one-migrant-per-generation strategy.
Optical losses in meta-structures based on metal subunits represents a central topic towards the fabrication of metamaterials in the visible range, since most of the extra-ordinary electromagnetic properties expected in these structured systems are shadowed by unavoidable absorptive effects. In this paper we report experimental studies aimed to demonstrate effective chemical and physical approaches to mitigate the radiation damping effect by means of ”gain assisted” and ”gain functionalized” coreshell metal nanospheres selected as metamaterial building blocks. A multiscale strategy has been utilized to compare these two systems, showing that in both cases partial loss compensation can be obtained.
The free radical nitric oxide (NO*) is involved in a variety of diverse biological processes from acting as a vasodilator in the cardiovascular system to being the rate-limiting component in the production of peroxynitrite (ONOO-), a contributor to neurodegenerative disorders such as multiple sclerosis (MS). Uric acid (UA), the end product of purine metabolism in humans and a selective inhibitor of toxic reactions attributed to radicals formed by the interaction of ONOO- and CO2, is generally low in MS patients. We investigated the relationship between serum ONOO-, CO2, and UA in MS patients and normal controls by comparing the circadian characteristics of the NO* metabolites nitrite/ nitrate (NO), CO2, and UA. In this preliminary study, we found the functional relationship ascribed to the circadian timing of the peak and trough levels of NO, CO2, and UA in healthy subjects to be clearly altered in MS patients. These findings suggest that alterations in the temporal relationship between the 24h pattern in serum ONOO- formation and UA may either contribute to or reflect the disease processes in MS.
Abstract The coalescent with recombination is a very useful tool in molecular population genetics. Under this framework, genealogies often represent the evolution of the substitution unit, and because of this, the few coalescent algorithms implemented for the simulation of coding sequences force recombination to occur only between codons. However, it is clear that recombination is expected to occur most often within codons. Here we have developed an algorithm that can evolve coding sequences under an ancestral recombination graph that represents the genealogies at each nucleotide site, thereby allowing for intracodon recombination. The algorithm is a modification of Hudson's coalescent in which, in addition to keeping track of events occurring in the ancestral material that reaches the sample, we need to keep track of events occurring in ancestral material that does not reach the sample but that is produced by intracodon recombination. We are able to show that at typical substitution rates the number of nonsynonymous changes induced by intracodon recombination is small and that intracodon recombination does not generally result in inflated estimates of the overall nonsynonymous/synonymous substitution ratio (ω). On the other hand, recombination can bias the estimation of ω at particular codons, resulting in apparent rate variation among sites and in the spurious identification of positively selected sites. Importantly, in this case, allowing for variable synonymous rates across sites greatly reduces the false-positive rate and recovers statistical power. Finally, coalescent simulations with intracodon recombination could be used to better represent the evolution of nuclear coding genes or fast-evolving pathogens such as HIV-1.We have implemented this algorithm in a computer program called NetRecodon, freely available at http://darwin.uvigo.es.
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Arachidonic acid (AA) is an essential fatty acid that is released by phospholipids in cell membranes and metabolized by cyclooxygenase (COX), cytochrome P450 (CYP) enzymes, and lipid oxygenase (LOX) pathways to regulate complex cardiovascular function under physiological and pathological conditions. Various AA metabolites include prostaglandins, prostacyclin, thromboxanes, hydroxyeicosatetraenoic acids, leukotrienes, lipoxins, and epoxyeicosatrienoic acids. The AA metabolites play important and differential roles in the modulation of vascular tone, and cardiovascular complications including atherosclerosis, hypertension, and myocardial infarction upon actions to different receptors and vascular beds. This article reviews the roles of AA metabolism in cardiovascular health and disease as well as their potential therapeutic implication.
Abstract Field experiments were performed in early March 2019 at the farm of the Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences. Four concentrations of nitrogen application were employed as follows: that is, urea applications 964, 482, 96, 0 kg ha − 1 , respectively. And 300 kg ha − 1 calcium, magnesium, and phosphorus were likewise applied in 4 different treatments. The results showed that the soil microbial biomass carbon and phosphorus were altered significantly by non- and low-nitrogen input. Moreover, the indexes of soil bacterial richness and diversity in the sugarcane field could be significantly improved, even by low nitrogen input. At the genus level, norank_f__SC-I-84 , Mycobacterium , norank_f__Micropepsaceae , norank_f__norank_o__Saccharimonadales , norank_f__norank_o__Subgroup_2 and norank_f__Acetobacteraceae were the unique dominant bacteria in the soil with the high nitrogen input treatment. norank_f__JG30-KF-CM45 and Jatrophihabitans were the unique dominant genera in the moderate nitrogen input treatment. norank_f__norank_o__norank_c__Subgroup_6 , HSB_OF53-F07 , Streptomyces , norank_f__67 − 14 , norank_f__norank_o__SBR1031 and norank_f__norank_o__norank_c__KD4-96 were the unique dominant genera in the low nitrogen input treatment. In contrast, FCPS473 , Actinospica , 1921-2 , Sinomonas , and norank_f__Ktedonobacteraceae were the unique dominant genera in CK (no nitrogen application treatment). It suggested that low nitrogen input was the most significant effect on the soil microbial biomass carbon and phosphorus in the sugarcane field. Moreover, low nitrogen input also can improve the diversity and richness of sugarcane soil bacteria. The dominant bacterial genera of low nitrogen input and the other treatments were different for the compositions of dominant bacteria, and the largest abundance difference of dominant bacterial genera was norank_f__norank_o__norank_c__Subgroup_6 . However, whether low nitrogen stress can improve the yield and quality of sugarcane warrants further research.
