4,218 research outputs found

    Total synthesis and biological evaluation of the tetramic acid based natural product harzianic acid and its stereoisomers

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    Financial support for this project was provided by Cancer Research UK (Grant No. C21383/A6950)The bioactive natural product harzianic acid was prepared for the first time in just six steps (longest linear sequence) with an overall yield of 22%. The identification of conditions to telescope amide bond formation and a Lacey-Dieckmann reaction into one pot proved important. The three stereoisomers of harzianic acid were also prepared, providing material for comparison of their biological activity. While all of the isomers promoted root growth, improved antifungal activity was unexpectedly associated with isomers in the enantiomeric series opposite that of harzianic acid.Publisher PDFPeer reviewe

    Threaded Structure and Blue Luminescence of (CuCN)20(Piperazine)7

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    The structurally unique and highly luminescent 20 : 7 complex of CuCN with piperazine (Pip) was formed under aqueous conditions; its structure reveals two interpenetrated 2D sub-networks in 6 : 1 ratio: (CuCN)2(Pip) and (CuCN)8(Pip), the latter consisting of Cu18(CN)16(Pip)2 macrocycles

    SoniBand: Understanding the Effects of Metaphorical Movement Sonifications on Body Perception and Physical Activity

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    Negative body perceptions are a major predictor of physical inactivity, a serious health concern. Sensory feedback can be used to alter such body perceptions; movement sonification, in particular, has been suggested to affect body perception and levels of physical activity (PA) in inactive people. We investigated how metaphorical sounds impact body perception and PA. We report two qualitative studies centered on performing different strengthening/flexibility exercises using SoniBand, a wearable that augments movement through different sounds. The first study involved physically active participants and served to obtain a nuanced understanding of the sonifications’ impact. The second, in the home of physically inactive participants, served to identify which effects could support PA adherence. Our findings show that movement sonification based on metaphors led to changes in body perception (e.g., feeling strong) and PA (e.g., repetitions) in both populations, but effects could differ according to the existing PA-level. We discuss principles for metaphor-based sonification design to foster PA

    Effects of pitch and musical sounds on body-representations when moving with sound

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    The effects of music on bodily movement and feelings, such as when people are dancing or engaged in physical activity, are well-documented—people may move in response to the sound cues, feel powerful, less tired. How sounds and bodily movements relate to create such effects? Here we deconstruct the problem and investigate how different auditory features affect people’s body-representation and feelings even when paired with the same movement. In three experiments, participants executed a simple arm raise synchronised with changing pitch in simple tones (Experiment 1), rich musical sounds (Experiment 2) and within different frequency ranges (Experiment 3), while we recorded indirect and direct measures on their movement, body-representations and feelings. Changes in pitch influenced people’s general emotional state as well as the various bodily dimensions investigated—movement, proprioceptive awareness and feelings about one’s body and movement. Adding harmonic content amplified the differences between ascending and descending sounds, while shifting the absolute frequency range had a general effect on movement amplitude, bodily feelings and emotional state. These results provide new insights in the role of auditory and musical features in dance and exercise, and have implications for the design of sound-based applications supporting movement expression, physical activity, or rehabilitation

    Connection Between Type A and E Factorizations and Construction of Satellite Algebras

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    Recently, we introduced a new class of symmetry algebras, called satellite algebras, which connect with one another wavefunctions belonging to different potentials of a given family, and corresponding to different energy eigenvalues. Here the role of the factorization method in the construction of such algebras is investigated. A general procedure for determining an so(2,2) or so(2,1) satellite algebra for all the Hamiltonians that admit a type E factorization is proposed. Such a procedure is based on the known relationship between type A and E factorizations, combined with an algebraization similar to that used in the construction of potential algebras. It is illustrated with the examples of the generalized Morse potential, the Rosen-Morse potential, the Kepler problem in a space of constant negative curvature, and, in each case, the conserved quantity is identified. It should be stressed that the method proposed is fairly general since the other factorization types may be considered as limiting cases of type A or E factorizations.Comment: 20 pages, LaTeX, no figure, to be published in J. Phys.

    Positronium Hyperfine Splitting in Non-commutative Space at the Order α6\alpha^6

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    We obtain positronium Hyperfine Splitting owing to the non-commutativity of space and show that, in the leading order, it is proportional to θα6\theta \alpha^6 where, θ\theta is the parameter of non-commutativity. It is also shown that spatial non-commutativity splits the spacing between n=2n=2 triplet excited levels E(23S1)→E(23P2)E(2^3S_1)\to E(2^3P_2) which provides an experimental test on the non-commutativity of space.Comment: 7 pages, 2 figures, to appear in Phys. Rev.

    LOS oligosaccharide modification enhances dendritic cell responses to meningococcal native outer membrane vesicles expressing a non toxic lipid A.

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    Outer membrane vesicles (OMV) are released by many bacteria, and contain immunogenic antigens in addition to harmful inflammatory factors, like lipopolysaccharides. Chemically detoxified OMV have been used in vaccines against Neisseria meningitidis (Nm), however little is known about their interaction with antigen presenting cells. In this study, we investigated the interaction of Nm OMV with human dendritic cells (DC) to gain further understanding of their biological activity. We engineered a novel serogroup B Nm that is unencapsulated (siaD), expresses pentacylated lipid A (lpxL1), hence conferring reduced toxicity, and expresses an lgtB oligosaccharide structure designed to target OMV to DC via DC-SIGN. We show that the lgtB moiety is critical for internalization of NOMV by DC. Furthermore, the lgtB moiety significantly enhances DC maturation, IL-10 and IL-23 production in the presence of a pentacylated lipid A. Whilst different DC phenotypes were observed for each NOMV, this had little effect on Th1 and Th2 cell differentiation, however lgtB significantly increased Th17 cell expansion in the presence of pentacylated lipid A. We believe that lgtB/lpxL1 NOMV should be considered further as a vaccine vector, particularly considering the importance of lgtB in antigen uptake and further human studies on antigen specific responses should be considered

    Procedure for the formulation of business opportunities. Case studies in the food industry

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    Given the importance of identifying business opportunities in the chemical and food process industry, considering available technologies and raw materials as well as potential markets, the objective of this work is to propose a heuristic procedure for the formulation of business opportunities applied to a case study of the food industry. The proposed procedure considers previous actions and methodological pro-cedures and establishes a sequence of actions that facilitate the selection and development of new business opportunities considering market possibilities and potentialities, assimilable technologies, strategic projection through the SWOT matrix, economic evaluation and sensitivity analysis. The importance of adequately establishing the technical and technological scheme of the process and the financial analysis of the business as a tool to facilitate the objective evaluation of the situation and the correct decision making is demonstrated. The proposed methodology was applied to a case study associated to primary and modified products of Manihot esculenta Cranz (cassava), determining the technological, environmental and technical-economic conditions that guarantee the effectiveness and sustainability of cassava-cookies, flour and starch production businesses as combined primary assortments and precolloidal starch as a structurally modified assortment

    Selective medium for culture of Mycoplasma hyopneumoniae

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    The fastidious porcine respiratory pathogen Mycoplasma hyopneumoniae has proven difficult to culture since it was first isolated in 1965. A reliable solid medium has been particularly challenging. Moreover, clinical and pathological samples often contain the fast-growing M. hyorhinis which contaminates and overgrows M. hyopneumoniae in primary culture. The aim of this study was to optimise the culture medium for recovery of M. hyopneumoniae and to devise a medium for selection of M. hyopneumoniae from clinical samples also containing M. hyorhinis. The solid medium devised by Niels Friis was improved by use of Purified agar and incorporation of DEAE-dextran. Addition of glucose or neutralization of acidity in liquid medium with NaOH did not improve the final yield of viable organisms or alter the timing of peak viability. Analysis of the relative susceptibility of M. hyopneumoniae and M. hyorhinis strains to four antimicrobials showed that M. hyopneumoniae is less susceptible than M. hyorhinis to kanamycin. This was consistent in all UK and Danish strains tested. A concentration of 2 μg/ml of kanamycin selectively inhibited the growth of all M. hyorhinis tested, while M. hyopneumoniae was able to grow. This forms the basis of an effective selective culture medium for M. hyopneumoniae.(Résumé d'auteur
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