Conditions that Stabilize Membrane Domains Also Antagonize n-Alcohol Anesthesia

Diverse molecules induce general anesthesia with potency strongly correlated with both their hydrophobicity and their effects on certain ion channels. We recently observed that several n -alcohol anesthetics inhibit heterogeneity in plasma-membrane-derived vesicles by lowering the critical temperature (Tc) for phase separation. Here, we exploit conditions that stabilize membrane heterogeneity to further test the correlation between the anesthetic potency of n -alcohols and effects on Tc. First, we show that hexadecanol acts oppositely to n -alcohol anesthetics on membrane mixing and antagonizes ethanol-induced anesthesia in a tadpole behavioral assay. Second, we show that two previously described “intoxication reversers” raise Tc and counter ethanol’s effects in vesicles, mimicking the findings of previous electrophysiological and behavioral measurements. Third, we find that elevated hydrostatic pressure, long known to reverse anesthesia, also raises Tc in vesicles with a magnitude that counters the effect of butanol at relevant concentrations and pressures. Taken together, these results demonstrate that ΔTc predicts anesthetic potency for n-alcohols better than hydrophobicity in a range of contexts, supporting a mechanistic role for membrane heterogeneity in general anesthesia

Ventilator-associated Pneumonia After Elective Cardiac Surgery Caused by Pneumocystis Jirovecii

Ventilator-associated pneumonia is a severe complication among patients undergoing cardiac surgery. Although hospital-acquired bacterial pathogens, often multidrug resistant, are the most frequent cause, non-bacterial atypical and opportunistic agents traditionally associated with immunocompromise are increasingly recognized. We describe ventilator-associated pneumonia due to Pneumocystis jirovecii in the absence of traditional risk factors for Pneumocystis pneumonia in a patient after cardiac surgery

Pneumocystis primary infection in non-immunosuppressed infants in Lima, Peru

Objectives: To provide original data on Pneumocystis primary infection in non-immunosuppressed infants from Peru. / Methods: A cross sectional study was performed. Infants less than seven months old, without any underlying medical conditions attending the “well baby” outpatient clinic at one hospital in Lima, Peru were prospectively enrolled during a 15-month period from November 2016 to February 2018. All had a nasopharyngeal aspirate (NPA) for detection of P. jirovecii DNA using a PCR assay, regardless of respiratory symptoms. P. jirovecii DNA detection was considered to represent pulmonary colonization contemporaneous with Pneumocystis primary infection. Associations between infants’ clinical and demographic characteristics and results of P. jirovecii DNA detection were analyzed. / Results: P. jirovecii DNA was detected in 45 of 146 infants (30.8%) and detection was not associated with concurrent respiratory symptoms in 40 of 45 infants. Infants with P. jirovecii had a lower mean age when compared to infants not colonized (p <0.05). The highest frequency of P. jirovecii was observed in 2-3-month-old infants (p < 0.01) and in the cooler winter and spring seasons (p <0.01). Multivariable analysis showed that infants living in a home with ≤ 1 bedroom were more likely to be colonized; Odds Ratio =3.03 (95%CI 1.31-7.00; p =0.01). / Conclusion: Pneumocystis primary infection in this single site in Lima, Peru, was most frequently observed in 2-3-month-old infants, in winter and spring seasons, and with higher detection rates being associated with household conditions favoring close inter-individual contacts and potential transmission of P. jirovecii

Mixture models for distance sampling detection functions

Funding: EPSRC DTGWe present a new class of models for the detection function in distance sampling surveys of wildlife populations, based on finite mixtures of simple parametric key functions such as the half-normal. The models share many of the features of the widely-used “key function plus series adjustment” (K+A) formulation: they are flexible, produce plausible shapes with a small number of parameters, allow incorporation of covariates in addition to distance and can be fitted using maximum likelihood. One important advantage over the K+A approach is that the mixtures are automatically monotonic non-increasing and non-negative, so constrained optimization is not required to ensure distance sampling assumptions are honoured. We compare the mixture formulation to the K+A approach using simulations to evaluate its applicability in a wide set of challenging situations. We also re-analyze four previously problematic real-world case studies. We find mixtures outperform K+A methods in many cases, particularly spiked line transect data (i.e., where detectability drops rapidly at small distances) and larger sample sizes. We recommend that current standard model selection methods for distance sampling detection functions are extended to include mixture models in the candidate set.Publisher PDFPeer reviewe

Nuclear Magnetic Resonance Imaging of Cured Polymers

Quantitative nondestructive evaluation (NDE) generally has two goals; the first is to obtain quantitative information about the mechanical and chemical properties of the sample, and the second is to obtain an image of the sample to reveal defects or anomalies. Neither approach independently gives sufficient information about the acceptability of the part, but if combined, the disposition of parts and processes can be determined

A Musico-Choreographic Analysis of a Cuban Dance Routine – A Performance-Informed Approach

McKerrell, in ‘Towards Practice Research in Ethnomusicology,’ advocates for performance to be used as ‘a central methodology,’ as a ‘translation of artistic performance aesthetics’ and as a ‘research outcome sited in original performance.’ (McKerrell 2019: 1). The translational role for performance is demonstrated in this article through a practice-led investigation into the dynamic relationship between improvised music and dance. The research is based on the analysis of a live performance on Cuban television of ‘Los Problemas de Atilana’ by Orquesta Aragón in the early 1960s, where musical gestures are shown to be embodied in the flute and dance solo ‘duet’ performed by Cuban flautist Richard Egües and dancer Rafael Bacallao, revealing the shared memories of a community bound by common cultural experience. Interdisciplinary in nature, analysis is undertaken by a musician-scholar, a film scholar-practitioner and a professional Cuban dancer-animator in order to unearth details of this embodied repertoire, thus translating and making overt culturally implicit knowledge for those outside of the artistic community of practice, and, in some cases, within it. Through re-performance and re-presentation in the form of a recording and animations, the many meanings embodied in the original performance are examined through analytical text, musical notation, visuals, recordings and animation film

On the Theory of Evolution Versus the Concept of Evolution: Three Observations

Here we address three misconceptions stated by Rice et al. in their observations of our article Paz-y-Miño and Espinosa (Evo Edu Outreach 2:655–675, 2009), published in this journal. The five authors titled their note “The Theory of Evolution is Not an Explanation for the Origin of Life.” First, we argue that it is fallacious to believe that because the formulation of the theory of evolution, as conceived in the 1800s, did not include an explanation for the origin of life, nor of the universe, the concept of evolution would not allow us to hypothesize the possible beginnings of life and its connections to the cosmos. Not only Stanley Miller’s experiments of 1953 led scientists to envision a continuum from the inorganic world to the origin and diversification of life, but also Darwin’s own writings of 1871. Second, to dismiss the notion of Rice et al. that evolution does not provide explanations concerning the universe or the cosmos, we identify compelling scientific discussions on the topics: Zaikowski et al. (Evo Edu Outreach 1:65–73, 2008), Krauss (Evo Edu Outreach 3:193–197, 2010), Peretó et al. (Orig Life Evol Biosph 39:395–406, 2009) and Follmann and Brownson (Naturwissenschaften 96:1265–1292, 2009). Third, although we acknowledge that the term Darwinism may not be inclusive of all new discoveries in evolution, and also that creationists and Intelligent Designers hijack the term to portray evolution as ideology, we demonstrate that there is no statistical evidence suggesting that the word Darwinism interferes with public acceptance of evolution, nor does the inclusion of the origin of life or the universe within the concept of evolution. We examine the epistemological and empirical distinction between the theory of evolution and the concept of evolution and conclude that, although the distinction is important, it should not compromise scientific logic

Seabird diving behaviour reveals the functional significance of shelf-sea fronts as foraging hotspots

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Oceanic fronts are key habitats for a diverse range of marine predators, yet how they influence fine-scale foraging behaviour is poorly understood. Here, we investigated the dive behaviour of northern gannets Morus bassanus in relation to shelf-sea fronts. We GPS tracked 53 breeding birds and examined the relationship between 1901 foraging dives (from time-depth recorders) and thermal fronts (identified via Earth Observation composite front mapping) in the Celtic Sea, North-East Atlantic. We (1) used a habitat use-availability analysis to determine whether gannets preferentially dived at fronts, and (2) compared dive characteristics in relation to fronts to investigate the functional significance of these oceanographic features. We found that relationships between gannet dive probabilities and fronts varied by frontal metric and sex. Whilst both sexes were more likely to dive in the presence of seasonally persistent fronts, links to more ephemeral features were less clear. Here, males were positively correlated with distance to front and cross-front gradient strength, with the reverse for females. Both sexes performed two dive strategies: shallow V-shaped plunge dives with little or no active swim phase (92% of dives), and deeper U-shaped dives with an active pursuit phase of at least three seconds (8% of dives). When foraging around fronts, gannets were half as likely to engage in U-shaped dives compared with V-shaped dives, independent of sex. Moreover, V-shaped dive durations were significantly shortened around fronts. These behavioural responses support the assertion that fronts are important foraging habitats for marine predators, and suggest a possible mechanistic link between the two in terms of dive behaviour. This research also emphasises the importance of cross-disciplinary research when attempting to understand marine ecosystems.This work was funded by a PhD studentship to SLC by the Natural Environment Research Council (NERC; NE/J500380/1), Natural Resources Wales (Seabirds Cymru) and a NERC grant (NE/H007466/1)

Purification and characterization of chitinase from Alcaligenes faecalis AU02 by utilizing marine wastes and its antioxidant activity

Marine waste is an abundant renewable source for the recovery of several value added metabolites with potential industrial applications. This study describes the production of chitinase on marine waste, with the subsequent use of the same marine waste for the extraction of antioxidants. A chitinase-producing bacterium isolated from seafood effluent was identified as Alcaligenes faecalis AU02. Optimal chitinase production was obtained in culture conditions of 37°C for 72 h in 100 ml medium containing 1% shrimp and crab shell powder (1:1) (w/v), 0.1% K2HPO4, and 0.05% MgSO4·7H2O. The molecular weight of chitinase was determined by SDS-PAGE to be 36 kDa. The optimum pH, temperature, pH stability, and thermal stability of chitinase were about 8, 37°C, 5–12, and 40–80°C, respectively. The antioxidant activity of A. faecalis AU02 culture supernatant was determined through scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) as 84%, and the antioxidant compound was characterized by TLC and its FT-IR spectrum. The present study proposed that marine wastes can be utilized to generate a high-value-added product and that pharmacological studies can extend its use to the field of medicine