1,158 research outputs found
Recolonization of mollusc assemblages in mangrove plantations damaged by Typhoon Chan-hom in the Philippines
We investigated the effects of a catastrophic typhoon on mollusc assemblages of damaged mangrove plantations of different ages. Molluscs were sampled from infaunal, epifaunal and arboreal assemblages of mangrove stands in Lingayen Gulf, northwest Philippines, and compared with assemblages of un-impacted areas. Prior to the occurrence of the typhoon, there were clear shifts in the species diversity (H’) and composition of mollusc assemblages with stand age of mangrove forests. This was observed in species composition through the succession in dominance from pioneer to seral or putative climax species, and assemblage type (as arboreal, epifaunal and infaunal). However, severe damage to vegetation structure and sediment properties (associated with a reduction in tree density and canopy cover resulting in increased temperatures and exposure) following the typhoon resulted in an alteration of trajectory patterns in the damaged stands. There were shifts in species composition and dominant species from having mature mangrove-associated species (pre-typhoon) to an abrupt return in dominance of pioneer species (post-typhoon). The damage was more evident in older stands than in intermediate-aged stands. Furthermore, the reduced presence of molluscs (and also probably their activities, i.e. burrowing) may have contributed to the delayed recovery of mangroves. The prospects for recovery of the system to pre-typhoon levels are therefore uncertain where the re-establishment of seral or edaphic mollusc assemblages appears to be related to the recovery of vegetation and sediment conditions
Efeito da altitude sobre o crescimento e desenvolvimento de quatro genótipos de mamona.
bitstream/CNPA/20178/1/COMTEC339.pd
Phylogenetic analysis of apicomplexan parasites infecting commercially valuable species from the North-East Atlantic reveals high levels of diversity and insights into the evolution of the group
Background: The Apicomplexa from aquatic environments are understudied relative to their terrestrial counterparts, and the seminal work assessing the phylogenetic relations of fish-infecting lineages is mostly based on freshwater hosts. The taxonomic uncertainty of some apicomplexan groups, such as the coccidia, is high and many genera were recently shown to be paraphyletic, questioning the value of strict morphological and ecological traits for parasite classification. Here, we surveyed the genetic diversity of the Apicomplexa in several commercially valuable vertebrates from the NorthEast Atlantic, including farmed fish. Results: Most of the sequences retrieved were closely related to common fish coccidia of Eimeria, Goussia and Calyptospora. However, some lineages from the shark Scyliorhinus canicula were placed as sister taxa to the Isospora, Caryospora and Schellakia group. Additionally, others from Pagrus caeruleostictus and Solea senegalensis belonged to an unknown apicomplexan group previously found in the Caribbean Sea, where it was sequenced from the water column, corals, and fish. Four distinct parasite lineages were found infecting farmed Dicentrarchus labrax or Sparus aurata. One of the lineages from farmed D. labrax was also found infecting wild counterparts, and another was also recovered from farmed S. aurata and farm-associated Diplodus sargus. Conclusions: Our results show that marine fish apicomplexans are diverse, and we highlight the need for a more extensive assessment of parasite diversity in this phylum. Additionally, parasites recovered from S. canicula were recovered as basal to their piscine counterparts reflecting hosts phylogeny
Dissecting the genetic overlap between severe mental disorders and markers of cellular aging: Identification of pleiotropic genes and druggable targets
Patients with severe mental disorders such as bipolar disorder (BD), schizophrenia (SCZ) and major depressive disorder (MDD) show a substantial reduction in life expectancy, increased incidence of comorbid medical conditions commonly observed with advanced age and alterations of aging hallmarks. While severe mental disorders are heritable, the extent to which genetic predisposition might contribute to accelerated cellular aging is not known. We used bivariate causal mixture models to quantify the trait-specific and shared architecture of mental disorders and 2 aging hallmarks (leukocyte telomere length [LTL] and mitochondrial DNA copy number), and the conjunctional false discovery rate method to detect shared genetic loci. We integrated gene expression data from brain regions from GTEx and used different tools to functionally annotate identified loci and investigate their druggability. Aging hallmarks showed low polygenicity compared with severe mental disorders. We observed a significant negative global genetic correlation between MDD and LTL (rg = −0.14, p = 6.5E−10), and no significant results for other severe mental disorders or for mtDNA-cn. However, conditional QQ plots and bivariate causal mixture models pointed to significant pleiotropy among all severe mental disorders and aging hallmarks. We identified genetic variants significantly shared between LTL and BD (n = 17), SCZ (n = 55) or MDD (n = 19), or mtDNA-cn and BD (n = 4), SCZ (n = 12) or MDD (n = 1), with mixed direction of effects. The exonic rs7909129 variant in the SORCS3 gene, encoding a member of the retromer complex involved in protein trafficking and intracellular/intercellular signaling, was associated with shorter LTL and increased predisposition to all severe mental disorders. Genetic variants underlying risk of SCZ or MDD and shorter LTL modulate expression of several druggable genes in different brain regions. Genistein, a phytoestrogen with anti-inflammatory and antioxidant effects, was an upstream regulator of 2 genes modulated by variants associated with risk of MDD and shorter LTL. While our results suggest that shared heritability might play a limited role in contributing to accelerated cellular aging in severe mental disorders, we identified shared genetic determinants and prioritized different druggable targets and compounds
Fatores de conversão do peso de cachos e frutos para peso de sementes de mamona.
bitstream/CNPA/19704/1/BOLETIM56.pd
Operating conditions of a simulated moving bed chromatography unit for the purification of fructooligosaccharides
C. Nobre acknowledges the F.C.T. - Fundacao para a Ciencia e a Tecnologia (Portugal) for the PhD Grant ref. SFRH/BD/32514/2006. A. Severino is funded by Belgian Fund for Scientific Research (F.S.R.- FNRS).This paper presents research results of the Belgian Network DYSCO (Dynamical Systems, Control, and Optimization), funded by the Interuniversity Attraction Poles Programme, initiated by the Belgian Federal Science Policy Office (BELSPO). The scientific responsibility rests with its authors
Vitellogenin Dynamics and Reproductive Morphology at Sexual Maturity of Philippine Mallard (Anas Platyrhynchos Domesticus L) Fed with Zinc Supplemented Diet
The vitellogenin (Vtg) is a precursor for the synthesis of egg yolk protein. Feeding with zinc-supplemented diet is hypothesized to increase the circulating Vtg thereby enhancing reproductive development. A total of 80 ducks,aged 16 weeks old, were randomly assigned to treatment groups; namely: group A with 40 ducks fed with 30 ppm zinc-supplemented diet (zinc positive) and group B with 40 ducks fed with no added zinc (zinc negative). Thecirculating Vtg at sexual maturity (155.11±10.83 days old) were determined from the blood sera. The sera were assayed for Vtg in duplicate using 96–well microplate and read the optical density at 415nm. The zinc concentrationof the samples was calculated using the nonlinear regression =OD = a x [Zn2+] / (b + [Zn2+]. Results show that the circulating Vtg in the blood sera of ducks at sexual maturity were 0.69±0.07 Gg Zn dL-1. The feeding of zinc-treateddiet had no significant influenced on the concentration of circulating Vtg. There was also insignificant difference in the reproductive morphology of ducks fed with or without added zinc. The Vtg concentration had no correlation withreproductive parameters but found to be positively correlated with liver weight (H=0.21) and negatively correlated with body weight (H = -0.24)
Descrição das fases do desenvolvimento reprodutivo da mamoneira visando ao manejo da colheita.
bitstream/CNPA/20891/1/CIRTEC115.pd
- …