Introduction : contemporary orientations in African cultural studies

Abstract: This paper offers a glimpse of work generated by the 2014 John Douglas Taylor conference on ‘Contemporary Orientations in African Cultural Studies’. The conference generated a number of inquiries into the time and place of contemporary African cultural work, many of which theorized beyond the frameworks that postcolonial and globalization studies frequently offer. Under the shifting paradigms of cultural studies, the work of this conference, as well as the current project, moves away from reading the African everyday as exclusively a construction out of a series of colonial histories and relationalities, or global cultural flows. In line with Jean and John Comaroffs’ Theory From the South, this issue is instead dedicated to relocating the global centres from which cultural studies emanates and positing African work’s challenge to normative zones of cultural critique. ‘Contemporary orientations’ attempts to relocate the time and space of critique in African studies, but it resists the gesture to posit a stable trajectory through which time moves. Rather, the terms of the contemporary and the orientation depend on how they are read in relation to a multitude of other temporalities, orientations, and objects

Light regime and growth phase affect the microalgal production of protein quantity and quality with Dunaliella salina

The microalga Dunaliella salina has been widely studied for carotenogenesis, yet its protein production for human nutrition has rarely been reported. This study unveils the effects of growth phase and light regime on protein and essential amino acid (EAA) levels in D. salina. Cultivation under 24-h continuous light was compared to 12-h/12-h light/dark cycle. The essential amino acid index (EAAI) of D. salina showed accumulating trends up to 1.53 in the stationary phase, surpassing FAO/WHO standard for human nutrition. Light/dark conditions inferred a higher light-usage efficiency, yielding 5–97% higher protein and 18–28% higher EAA mass on light energy throughout the growth, accompanied by 138% faster growth during the light phase of the light/dark cycle, compared to continuous light. The findings revealed D. salina to be especially suitable for high-quality protein production, particularly grown under light/dark conditions, with nitrogen limitation as possible trigger, and harvested in the stationary phase

Prospects for viruses infecting eukaryotic microalgae in biotechnology

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Effect of phosphorus limitation on Se uptake efficiency in the microalga Nannochloropsis oceanica

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The nucleolus as a genomic safe harbor for strong gene expression in Nannochloropsis oceanica

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Enhancement of co-production of nutritional protein and carotenoids in Dunaliella salina using a two-phase cultivation assisted by nitrogen level and light intensity

Microalga Dunaliella salina is known for its carotenogenesis. At the same time, it can also produce high-quality protein. The optimal conditions for D. salina to co-produce intracellular pools of both compounds, however, are yet unknown. This study investigated a two-phase cultivation strategy to optimize combined high-quality protein and carotenoid production of D. salina. In phase-one, a gradient of nitrogen concentrations was tested. In phase-two, effects of nitrogen pulse and high illumination were tested. Results reveal optimized protein quantity, quality (expressed as essential amino acid index EAAI) and carotenoids content in a two-phase cultivation, where short nitrogen starvation in phase-one was followed by high illumination during phase-two. Adopting this strategy, productivities of protein, EAA and carotenoids reached 22, 7 and 3 mg/L/d, respectively, with an EAAI of 1.1. The quality of this biomass surpasses FAO/WHO standard for human nutrition, and the observed level of β-carotene presents high antioxidant pro-vitamin A activity

Effect of sulphur on selenium accumulation and speciation in Nannochloropsis oceanica

Sulphur (S) and selenium (Se) are chemically similar. Once Se is taken up, it substitutes S in S-containing amino acids. This study investigated the effect of S on selenite accumulation in the microalga Nannochloropsis oceanica. [0–28 mM] S concentrations and selenite concentrations of 0 and 30 µM were tested. S concentrations of = 3 mM led to decreased cell growth whereas cultures with = 4 mM were not growth limited. Se accumulation increased up to 8-fold when using S = 2 mM and decreased with S 28 mM. The average relative abundance of organic Se species was selenomethionine (SeMet) 98.2 %, selenocystine (SeCys2) 1.4 % and selenomethyl selenocysteine (SeMeSeCys) 0.4 %. Total fatty acids were not affected by S limitation or Se presence. This is the first study on the effect of S on selenite accumulation, organic Se speciation of N. oceanica and its potential as an organic Se-enriched food/feed ingredient.This manuscript is part of a PhD programme funded by the Green Aquaculture Intensification in Europe (GAIN) project that received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 773330. We are grateful for the preliminary literature review conducted by Judith Ham who unfortunately could not perform any laboratory work due to Covid-19 restrictions. We would like to thank Wendy Evers for her help in measuring the fatty acids. Ana Arias-Borrego and Tamara García-Barrera were supported by the project PG2018-096608-B-C21 from the Spanish Ministry of Science and innovation (MCIN). Generaci´on del Conocimiento. MCIN/ AEI /10.13039/501100011033/ FEDER “Una manera de hacer Europa”

Things come in threes: A new complex allele and a novel deletion within the CFTR gene complicate an accurate diagnosis of cystic fibrosis

Background: Despite consolidated guidelines, the clinical diagnosis and prognosis of cystic fibrosis (CF) is still challenging mainly because of the extensive phenotypic heterogeneity and the high number of CFTR variants, including their combinations as complex alleles. Results: We report a family with a complicated syndromic phenotype, which led to the suspicion not only of CF, but of a dominantly inherited skeletal dysplasia (SD). Whereas the molecular basis of the SD was not clarified, segregation analysis was central to make a correct molecular diagnosis of CF, as it allowed to identify three CFTR variants encompassing two known maternal mutations and a novel paternal microdeletion. Conclusion: This case well illustrates possible pitfalls in the clinical and molecular diagnosis of CF; presence of complex phenotypes deflecting clinicians from appropriate CF recognition, and/or identification of two mutations assumed to be in trans but with an unconfirmed status, which underline the importance of an in-depth molecular CFTR analysis

De novo point mutations in patients diagnosed with ataxic cerebral palsy

Cerebral palsy is commonly attributed to perinatal asphyxia. However, Schnekenberg et al. describe here four individuals with ataxic cerebral palsy likely due to de novo dominant mutations associated with increased paternal age. Therefore, patients with cerebral palsy should be investigated for genetic causes before the disorder is ascribed to asphyxi

Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization.

The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ∼8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD