Polarimetry and Spectroscopy of the `Oxygen Flaring' DQ Herculis-like nova: V5668 Sagittarii (2015)

Classical novae are eruptions on the surface of a white dwarf in a binary system. The material ejected from the white dwarf surface generally forms an axisymmetric shell of gas and dust around the system. The three-dimensional structure of these shells is difficult to untangle when viewed on the plane of the sky. In this work a geometrical model is developed to explain new observations of the 2015 nova V5668 Sagittarii. To understand the ionisation structure in terms of the nova shell morphology and estimate the emission distribution directly following the light-curve's dust-dip. High-cadence optical polarimetry and spectroscopy observations of a nova are presented. The ejecta is modelled in terms of morpho-kinematics and photoionisation structure. Initially observational results are presented, including broadband polarimetry and spectroscopy of V5668 Sgr nova during eruption. Variability over these observations provides clues towards the evolving structure of the nova shell. The position angle of the shell is derived from polarimetry, which is attributed to scattering from small dust grains. Shocks in the nova outflow are suggested in the photometry and the effect of these on the nova shell are illustrated with various physical diagnostics. Changes in density and temperature as the super soft source phase of the nova began are discussed. Gas densities are found to be of the order of 10$^{9}$ cm$^{-3}$ for the nova in its auroral phase. The blackbody temperature of the central stellar system is estimated to be around $2.2\times10^{5}$ K at times coincident with the super soft source turn-on. It was found that the blend around 4640 $\rm{\AA}$ commonly called `nitrogen flaring' is more naturally explained as flaring of the O~{\sc ii} multiplet (V1) from 4638 - 4696 $\rm{\AA}$, i.e. `oxygen flaring'

3-Methyl-1-butanol production in Escherichia coli: random mutagenesis and two-phase fermentation

Interest in producing biofuels from renewable sources has escalated due to energy and environmental concerns. Recently, the production of higher chain alcohols from 2-keto acid pathways has shown significant progress. In this paper, we demonstrate a mutagenesis approach in developing a strain of Escherichia coli for the production of 3-methyl-1-butanol by leveraging selective pressure toward l-leucine biosynthesis and screening for increased alcohol production. Random mutagenesis and selection with 4-aza-d,l-leucine, a structural analogue to l-leucine, resulted in the development of a new strain of E. coli able to produce 4.4 g/L of 3-methyl-1-butanol. Investigation of the host’s sensitivity to 3-methyl-1-butanol directed development of a two-phase fermentation process in which titers reached 9.5 g/L of 3-methyl-1-butanol with a yield of 0.11 g/g glucose after 60 h

Restriction of meat, fish, and poultry in omnivores improves mood: A pilot randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Omnivorous diets are high in arachidonic acid (AA) compared to vegetarian diets. Research shows that high intakes of AA promote changes in brain that can disturb mood. Omnivores who eat fish regularly increase their intakes of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), fats that oppose the negative effects of AA in vivo. In a recent cross-sectional study, omnivores reported significantly worse mood than vegetarians despite higher intakes of EPA and DHA. This study investigated the impact of restricting meat, fish, and poultry on mood.</p> <p>Findings</p> <p>Thirty-nine omnivores were randomly assigned to a control group consuming meat, fish, and poultry daily (OMN); a group consuming fish 3-4 times weekly but avoiding meat and poultry (FISH), or a vegetarian group avoiding meat, fish, and poultry (VEG). At baseline and after two weeks, participants completed a food frequency questionnaire, the Profile of Mood States questionnaire and the Depression Anxiety and Stress Scales. After the diet intervention, VEG participants reduced their EPA, DHA, and AA intakes, while FISH participants increased their EPA and DHA intakes. Mood scores were unchanged for OMN or FISH participants, but several mood scores for VEG participants improved significantly after two weeks.</p> <p>Conclusions</p> <p>Restricting meat, fish, and poultry improved some domains of short-term mood state in modern omnivores. To our knowledge, this is the first trial to examine the impact of restricting meat, fish, and poultry on mood state in omnivores.</p

Expression and Localization of Mitochondrial Ferritin mRNA in Alzheimer's Disease Cerebral Cortex

Mitochondrial ferritin (MtF) has been identified as a novel ferritin encoded by an intron-lacking gene with specific mitochondrial localization located on chromosome 5q23.1. MtF has been associated with neurodegenerative disorders such as Friedreich ataxia and restless leg syndrome. However, little information is available about MtF in Alzheimer's disease (AD). In this study, therefore, we investigated the expression and localization of MtF messenger RNA (mRNA) in the cerebral cortex of AD and control cases using real-time polymerase chain reaction (PCR) as well as in situ hybridization histochemistry. We also examined protein expression using western-blot assay. In addition, we used in vitro methods to further explore the effect of oxidative stress and β-amyloid peptide (Aβ) on MtF expression. To do this we examined MtF mRNA and protein expression changes in the human neuroblastoma cell line, IMR-32, after treatment with Aβ, H2O2, or both. The neuroprotective effect of MtF on oxidative stress induced by H2O2 was measured by MTT assay. The in situ hybridization studies revealed that MtF mRNA was detected mainly in neurons to a lesser degree in glial cells in the cerebral cortex. The staining intensity and the number of positive cells were increased in the cerebral cortex of AD patients. Real-time PCR and western-blot confirmed that MtF expression levels in the cerebral cortex were significantly higher in AD cases than that in control cases at both the mRNA and the protein level. Cell culture experiments demonstrated that the expression of both MtF mRNA and protein were increased by treatment with H2O2 or a combination of Aβ and H2O2, but not with Aβ alone. Finally, MtF expression showed a significant neuroprotective effect against H2O2-induced oxidative stress (p<0.05). The present study suggests that MtF is involved in the pathology of AD and may play a neuroprotective role against oxidative stress

Spatial competition shapes the dynamic mutational landscape of normal esophageal epithelium.

During aging, progenitor cells acquire mutations, which may generate clones that colonize the surrounding tissue. By middle age, normal human tissues, including the esophageal epithelium (EE), become a patchwork of mutant clones. Despite their relevance for understanding aging and cancer, the processes that underpin mutational selection in normal tissues remain poorly understood. Here, we investigated this issue in the esophageal epithelium of mutagen-treated mice. Deep sequencing identified numerous mutant clones with multiple genes under positive selection, including Notch1, Notch2 and Trp53, which are also selected in human esophageal epithelium. Transgenic lineage tracing revealed strong clonal competition that evolved over time. Clone dynamics were consistent with a simple model in which the proliferative advantage conferred by positively selected mutations depends on the nature of the neighboring cells. When clones with similar competitive fitness collide, mutant cell fate reverts towards homeostasis, a constraint that explains how selection operates in normal-appearing epithelium.This work was supported by grants from the Wellcome Trust to the Wellcome SangerInstitute (098051 and 296194) and Cancer Research UK Programme Grants to P.H.J.(C609/A17257 and C609/A27326). G.P. is supported by a Talento program fellowship from Comunidad de Madrid. B.A.H. and M.W.J.H. are supported by the MedicalResearch Council (Grant-in-Aid to the MRC Cancer unit grant no. MC_UU_12022/9 and NIRG to B.A.H. grant no. MR/S000216/1). M.W.J.H. acknowledges support fromthe Harrison Watson Fund at Clare College, Cambridge. B.A.H. acknowledges support from the Royal Society (grant no. UF130039). I.M. is funded by Cancer Research UK (C57387/A21777). S.D. benefited from the award of an ESPOD fellowship, 2018-21, from the Wellcome Sanger Institute and the European Bioinformatics Institute EMBL-EBI

Subjecting Elite Athletes to Inspiratory Breathing Load Reveals Behavioral and Neural Signatures of Optimal Performers in Extreme Environments

Background: It is unclear whether and how elite athletes process physiological or psychological challenges differently than healthy comparison subjects. In general, individuals optimize exercise level as it relates to differences between expected and experienced exertion, which can be conceptualized as a body prediction error. The process of computing a body prediction error involves the insular cortex, which is important for interoception, i.e. the sense of the physiological condition of the body. Thus, optimal performance may be related to efficient minimization of the body prediction error. We examined the hypothesis that elite athletes, compared to control subjects, show attenuated insular cortex activation during an aversive interoceptive challenge. Methodology/Principal Findings: Elite adventure racers (n = 10) and healthy volunteers (n = 11) performed a continuous performance task with varying degrees of a non-hypercapnic breathing load while undergoing functional magnetic resonance imaging. The results indicate that (1) non-hypercapnic inspiratory breathing load is an aversive experience associated with a profound activation of a distributed set of brain areas including bilateral insula, dorsolateral prefrontal cortex and anterior cingulated; (2) adventure racers relative to comparison subjects show greater accuracy on the continuous performance task during the aversive interoceptive condition; and (3) adventure racers show an attenuated right insula cortex response during and following the aversive interoceptive condition of non-hypercapnic inspirator

Evaluation of Protocol Uniformity Concerning Laparoscopic Cholecystectomy in The Netherlands

Background: Iatrogenic bile duct injury remains a current complication of laparoscopic cholecystectomy. One uniform and standardized protocol, based on the "critical view of safety" concept of Strasberg, should red

Dietary zinc supplementation of 3xTg-AD mice increases BDNF levels and prevents cognitive deficits as well as mitochondrial dysfunction

The overall effect of brain zinc (Zn2+) in the progression and development of Alzheimer's disease (AD) is still not completely understood. Although an excess of Zn2+ can exacerbate the pathological features of AD, a deficit of Zn2+ intake has also been shown to increase the volume of amyloid plaques in AD transgenic mice. In this study, we investigated the effect of dietary Zn2+ supplementation (30 p.p.m.) in a transgenic mouse model of AD, the 3xTg-AD, that expresses both β amyloid (Aβ)- and tau-dependent pathology. We found that Zn2+ supplementation greatly delays hippocampal-dependent memory deficits and strongly reduces both Aβ and tau pathology in the hippocampus. We also evaluated signs of mitochondrial dysfunction and found that Zn2+ supplementation prevents the age-dependent respiratory deficits we observed in untreated 3xTg-AD mice. Finally, we found that Zn2+ supplementation greatly increases the levels of brain-derived neurotrophic factor (BDNF) of treated 3xTg-AD mice. In summary, our data support the idea that controlling the brain Zn2+ homeostasis may be beneficial in the treatment of AD

Engineering Corynebacterium glutamicum for isobutanol production

The production of isobutanol in microorganisms has recently been achieved by harnessing the highly active 2-keto acid pathways. Since these 2-keto acids are precursors of amino acids, we aimed to construct an isobutanol production platform in Corynebacterium glutamicum, a well-known amino-acid-producing microorganism. Analysis of this host’s sensitivity to isobutanol toxicity revealed that C. glutamicum shows an increased tolerance to isobutanol relative to Escherichia coli. Overexpression of alsS of Bacillus subtilis, ilvC and ilvD of C. glutamicum, kivd of Lactococcus lactis, and a native alcohol dehydrogenase, adhA, led to the production of 2.6 g/L isobutanol and 0.4 g/L 3-methyl-1-butanol in 48 h. In addition, other higher chain alcohols such as 1-propanol, 2-methyl-1-butanol, 1-butanol, and 2-phenylethanol were also detected as byproducts. Using longer-term batch cultures, isobutanol titers reached 4.0 g/L after 96 h with wild-type C. glutamicum as a host. Upon the inactivation of several genes to direct more carbon through the isobutanol pathway, we increased production by ∼25% to 4.9 g/L isobutanol in a ∆pyc∆ldh background. These results show promise in engineering C. glutamicum for higher chain alcohol production using the 2-keto acid pathways

Assessing the Quality of Goal Setting in Behavioural Support for Smoking Cessation and its Association with Outcomes

BACKGROUND: Smoking cessation behavioural support can be effective but practitioners differ markedly in effectiveness, possibly due to variation in the quality of delivery of key behaviour change techniques, such as goal setting (i.e. setting a quit date). OBJECTIVES: This study aimed to (i) develop a reliable method for assessing the quality of practitioners' support in setting quit dates and (ii) assess whether quality predicts initiation of abstinence as a first step to quitting. METHODS: A scale for scoring the quality of goal setting was developed from national guidance documents and applied to 85 transcribed behavioural support sessions. Inter-rater reliability was assessed. Associations between quality scores and quit attempts were assessed. RESULTS: The 10-item scale produced had good inter-rater reliability (Kappa = 0.68). Higher quality goal setting was associated with increased self-reported quit attempts (p < .001; OR = 2.60, 95 % CI 1.54-4.40). The scale components 'set a clear quit date' (χ (2) (2, N = 85) = 22.3, p < .001) and 'within an appropriate timeframe' (χ (2) (2, N = 85) = 15.5, p < .001) were independently associated with quit attempts. CONCLUSIONS: It is possible to reliably assess the quality of goal setting in smoking cessation behavioural support. Higher quality of goal setting is associated with greater likelihood of initiating quit attempts