49 research outputs found

    The lambda-dimension of commutative arithmetic rings

    Full text link
    It is shown that every commutative arithmetic ring RR has lambdalambda-dimension leq3 leq 3. An example of a commutative Kaplansky ring with lambda lambda-dimension 3 is given. If RR satisfies an additional condition then lambda lambda-dim(RR

    Electrocatalytic hydrogen evolution by an iron complex containing a nitro-functionalized polypyridyl ligand

    Get PDF
    Iron polypyridyl complexes have recently been reported to electrocatalytically reduce protons to hydrogen gas at -1.57 V versus Fc(+)/Fc. A new iron catalyst with a nitro-functionalized polypyridyl ligand has been synthesized and found to be active for proton reduction. Interestingly, catalysis occurs at -1.18 V versus Fc(+)/Fc for the nitro-functionalized complex, resulting in an overpotential of 300 mV. Additionally, the complex is active with a turnover frequency of 550 s(-1). Catalysis is also observed in the presence of water with a 12% enhancement in activity. (C) 2015 Elsevier Ltd. All rights reserved

    Effects of the total replacement of fish-based diet with plant-based diet on the hepatic transcriptome of two European sea bass (Dicentrarchus labrax) half-sibfamilies showing different growth rates with the plant-based diet

    Get PDF
    Background: Efforts towards utilisation of diets without fish meal (FM) or fish oil (FO) in finfish aquaculture have been being made for more than two decades. Metabolic responses to substitution of fishery products have been shown to impact growth performance and immune system of fish as well as their subsequent nutritional value, particularly in marine fish species, which exhibit low capacity for biosynthesis of long-chain poly-unsaturated fatty acids (LC-PUFA). The main objective of the present study was to analyse the effects of a plant-based diet on the hepatic transcriptome of European sea bass (Dicentrarchus labrax). Results: We report the first results obtained using a transcriptomic approach on the liver of two half-sibfamilies of the European sea bass that exhibit similar growth rates when fed a fish-based diet (FD), but significantly different growth rates when fed an all-plant diet (VD). Overall gene expression was analysed using oligo DNA microarrays (GPL9663). Statistical analysis identified 582 unique annotated genes differentially expressed between groups of fish fed the two diets, 199 genes regulated by genetic factors, and 72 genes that exhibited diet-family interactions. The expression of several genes involved in the LC-PUFA and cholesterol biosynthetic pathways was found to be up-regulated in fish fed VD, suggesting a stimulation of the lipogenic pathways. No significant diet-family interaction for the regulation of LC-PUFA biosynthesis pathways could be detected by microarray analysis. This result was in agreement with LC-PUFA profiles, which were found to be similar in the flesh of the two half-sibfamilies. In addition, the combination of our transcriptomic data with an analysis of plasmatic immune parameters revealed a stimulation of complement activity associated with an immunodeficiency in the fish fed VD, and different inflammatory status between the two half-sibfamilies. Biological processes related to protein catabolism, amino acid transaminations, RNA splicing and blood coagulation were also found to be regulated by diet, while the expression of genes involved in protein and ATP synthesis differed between the half-sibfamilies. Conclusions: Overall, the combined gene expression, compositional and biochemical studies demonstrated a large panel of metabolic and physiological effects induced by total substitution of both FM and FO in the diets of European sea bass and revealed physiological characteristics associated with the two half-sibfamilies

    Finitely Presented Modules Over Semihereditary Rings

    No full text

    Prevalence of reticular pseudodrusen in age‐related macular degeneration with newly diagnosed choroidal neovascularisation

    No full text
    AIM: To investigate the prevalence of reticular pseudodrusen (RPD) in eyes of patients presenting with newly diagnosed choroidal neovascularisation (CNV) in age‐related macular degeneration (AMD), and to analyse the association between RPD, age‐related maculopathy (ARM) and AMD. METHOD: Two observational consecutive prospective series. In series 1, patients with AMD with newly diagnosed CNV were sampled to determine the incidence of RPD. Eyes with and without RPD were compared by the Mann–Whitney non‐parametric test and Fisher's exact test for age, sex of patients, the eye involved and type of CNV. Series 2 comprised 100 patients referred for fundus photography, fluorescein and/or indocyanine green angiography, for whom pictures showed RPD. This second cohort was then selected from a larger group of patients. RESULTS: Patients with newly diagnosed CNV in series 1 comprised 67 women and 33 men, aged 57–96 years (mean 79.5). CNV was “classic” (32 eyes), “occult” (41) or exhibited vascularised pigment epithelial detachment (PED, 11), retinal angiomatous proliferation (RAP) with or without PED (13), or haemorrhagic or fibrovascular scarring (3). In all, 24 (24%) eyes had RPD. The prevalence of RAP was significantly higher in eyes with RPD than in those without (p = 0.0128), despite the small number of patients with RAP. In series 2, 100 patients with RPD were enrolled in 3 months, and corresponded to 8% of the overall cases referred to our centre (Centre Ophtalmologique d'Imagerie et de Laser, Paris, France). There were 77 women and 23 men, aged 54–93 years (mean 79.2). Eyes with RPD (n = 155) usually exhibited signs of ARM or AMD, including soft drusen (101 eyes) and/or retinal pigment epithelium abnormalities (70), geographical atrophy (27) and/or CNV (61). In both studies, examination of blue‐light fundus pictures was extremely helpful in diagnosing RPD. CONCLUSION: RPD have a high prevalence among patients with AMD with newly diagnosed CNV (24% of cases). RPD were commonly associated with ARM or AMD. This study suggests that eyes with RPD could be classified as a phenotype of ARM
    corecore