157 research outputs found

    Hydrothermal Extraction of Microalgae Fatty Acid Influences Hydrochar Phytotoxicity

    Get PDF
    Hydrothermal carbonization (HTC) of microalgae biomass for the production of triacylglycerides is a potentially valuable enabling technology for a waste water treatment-based integrated biorefinery. Here, HTC was used to treat Phaeodactylum tricornutum lipid-rich biomass producing a solid hydrochar from the surface of which adsorbed lipids were removed by hexane extraction following filtration of the solid hydrochar from the process liquid product. Approximately 7% of the input biomass was recovered and transesterified for qualitative and quantitative GC-MS analysis for fatty acid methyl esters. Transesterifiable lipids accounted for 94% of the material recovered by solvent extraction. Of the transesterified fatty acids (FA) analyzed, the majority was monounsaturated (40.4%) and saturated (37%) C-16 FA. Other FA detected included saturated and monounsaturated C-18 (7.7 and 1.9%) and saturated C-14 (5.3%) and C-25 (1.5%). Thermal analysis (TGA/DSC) of the hydrochar in air showed calorific values of 10.6 MJ kg−1 (delipidated hydrochar) and 3.1 MJ kg−1 (non-delipidated hydrochar) with the latter exhibiting the presence of volatalizable components. Germination trials were conducted to assess the potential phytotoxic effects of these hydrochars. Delipidated hydrochar showed a germination index of 73% suggesting the presence of some phytotoxicity. Non-delipidated hydrochar showed high germination index results of 102% (unground) and 126% (ground). Taken together with the observation of reduced root hair proliferation in these two test conditions, this suggests the operation of a second phytotoxic effect that is removed by delipidation

    Alcohol expectancies in childhood: Change with the onset of drinking and ability to predict adolescent drunkenness and binge drinking

    Full text link
    Aims: Childhood expectancies about alcohol are present long before drinking begins. We examined the relationship between alcohol expectancies in childhood and onset of drinking, binge drinking, and drunkenness in adolescence and the influence of drinking onset on development of alcohol expectancies. Design: A prospective, longitudinal study of children assessed for alcohol expectancies and drinking at 4 time points between ages 6 and 17. Setting: Community study of families at high risk for alcoholism conducted in a 4-county area in the Midwest. Participants: The study involved 614 children; 460 were children of alcoholics and 70% were male. Measurements: Expectancies about effects of alcohol were measured using the Beverage Opinion Questionnaire and child’s drinking was measured using the Drinking and Drug History - Youth Form. Findings: Partial factor invariance was found for expectancy factors from age 6 to age 17. Survival analysis showed that social/relaxation expectancies in childhood predicted time to onset of binge drinking and first time drunk (Wald chi-square, 1 d.f. = 3.8, p < .05 and 5.1, p < .05, respectively). The reciprocal effect was also present; when adolescents began drinking, there was an increase in social/relaxation expectancy and a concomitant increase in slope of the expectancy change lasting throughout adolescence. Conclusions: A reciprocal relationship exists between childhood alcohol expectancies and involvement with alcohol. Higher expectancies for positive effects predict earlier onset of problem drinking. Onset of use, in turn, predicts an increase in rate of development of positive expectancies.NIH R37 AA07065 K01AA016591Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110697/1/Jester alcohol expectancies.pdfDescription of Jester alcohol expectancies.pdf : Main articl

    Sites of persistence of Fusobacterium necrophorum and Dichelobacter nodosus: a paradigm shift in understanding the epidemiology of footrot in sheep

    Get PDF
    Sites of persistence of bacterial pathogens contribute to disease dynamics of bacterial diseases. Footrot is a globally important bacterial disease that reduces health and productivity of sheep. It is caused by Dichelobacter nodosus, a pathogen apparently highly specialised for feet, while Fusobacterium necrophorum, a secondary pathogen in footrot is reportedly ubiquitous on pasture. Two prospective longitudinal studies were conducted to investigate the persistence of D. nodosus and F. necrophorum in sheep feet, mouths and faeces, and in soil. Molecular tools were used to detect species, strains and communities. In contrast to the existing paradigm, F. necrophorum persisted on footrot diseased feet, and in mouths and faeces; different strains were detected in feet and mouths. D. nodosus persisted in soil and on diseased, but not healthy, feet; similar strains were detected on both healthy and diseased feet of diseased sheep. We conclude that D. nodosus and F. necrophorum depend on sheep for persistence but use different strategies to persist and spread between sheep within and between flocks. Elimination of F. necrophorum would be challenging due to faecal shedding. In contrast D. nodosus could be eliminated if all footrot-affected sheep were removed and fade out of D. nodosus occurred in the environment before re-infection of a foot

    The material soul: Strategies for naturalising the soul in an early modern epicurean context

    Get PDF
    We usually portray the early modern period as one characterised by the ‘birth of subjectivity’ with Luther and Descartes as two alternate representatives of this radical break with the past, each ushering in the new era in which ‘I’ am the locus of judgements about the world. A sub-narrative called ‘the mind-body problem’ recounts how Cartesian dualism, responding to the new promise of a mechanistic science of nature, “split off” the world of the soul/mind/self from the world of extended, physical substance—a split which has preoccupied the philosophy of mind up until the present day. We would like to call attention to a different constellation of texts—neither a robust ‘tradition’ nor an isolated ‘episode’, somewhere in between—which have in common their indebtedness to, and promotion of an embodied, Epicurean approach to the soul. These texts follow the evocative hint given in Lucretius’ De rerum natura that ‘the soul is to the body as scent is to incense’ (in an anonymous early modern French version). They neither assert the autonomy of the soul, nor the dualism of body and soul, nor again a sheer physicalism in which ‘intentional’ properties are reduced to the basic properties of matter. Rather, to borrow the title of one of these treatises (L’Âme Matérielle), they seek to articulate the concept of a material soul. We reconstruct the intellectual development of a corporeal, mortal and ultimately material soul, in between medicine, natural philosophy and metaphysics, including discussions of Malebranche and Willis, but focusing primarily on texts including the 1675 Discours anatomiques by the Epicurean physician Guillaume Lamy; the anonymous manuscript from circa 1725 entitled L’Âme Matérielle, which is essentially a compendium of texts from the later seventeenth century (Malebranche, Bayle) along with excerpts from Lucretius; and materialist writings such Julien Offray de La Mettrie’s L’Homme-Machine (1748), in order to articulate this concept of a ‘material soul’ with its implications for notions of embodiment, materialism and selfhood

    Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches

    Get PDF
    Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly
    corecore