347 research outputs found

    Outcome selection, measurement and reporting for new surgical procedures and devices:a systematic review of IDEAL/IDEAL-D studies to inform development of a core outcome set

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    BackgroundOutcome selection, measurement and reporting for the evaluation of new surgical procedures and devices is inconsistent and lacks standardization. A core outcome set may promote the safe and transparent evaluation of surgical innovations. This systematic review examined outcome selection, measurement and reporting in studies conducted within the IDEAL (Idea, Development, Exploration, Assessment and Long‐term monitoring) framework to examine current practice and inform the development of a core outcome set for early‐phase studies of surgical procedures/devices.MethodsWeb of Science and Scopus citation searches were performed to identify author‐reported IDEAL/IDEAL‐D studies for any surgical procedure/device. Outcomes were extracted verbatim, including contextual information regarding outcome selection and measurement. Outcomes were categorized to inform a conceptual framework of outcome domains relevant to evaluating innovation.ResultsSome 48 studies were identified. Outcome selection, measurement and reporting varied widely across studies in different IDEAL stages. From 1737 outcomes extracted, 22 domains specific to evaluating innovation were conceptualized under seven broad categories: procedure completion success/failure; modifications; unanticipated events; surgeons' experiences; patients' experiences; resource use specific to the innovative procedure/device; and other innovation‐specific outcomes. Most innovation‐specific outcomes were measured and reported in only a small number of studies.ConclusionThis review highlighted the need for guidance and standardization in outcome selection and reporting in the evaluation of new surgical procedures/devices. Novel outcome domains specific to innovation have been identified to establish a core outcome set for future evaluations of surgical innovations

    Simultaneous saccharification and fermentation of steam exploded duckweed: Improvement of the ethanol yield by increasing yeast titre

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    This study investigated the conversion of Lemna minor biomass to bioethanol. The biomass was pre-treated by steam explosion (SE, 210 °C, 10 min) and then subjected to simultaneous saccharification and fermentation (SSF) using CellicÒ CTec 2 (20 U or 0.87 FPU gﰂ1 substrate) cellulase plus b-glucosidase (2 U gﰂ1 substrate) and a yeast inoculum of 10% (v/v or 8.0 ﰀ 107 cells mLﰂ1). At a substrate concentration of 1% (w/v) an ethanol yield of 80% (w/w, theoretical) was achieved. However at a substrate concentration of 20% (w/v), the ethanol yield was lowered to 18.8% (w/w, theoretical). Yields were considerably improved by increasing the yeast titre in the inoculum or preconditioning the yeast on steam exploded liquor. These approaches enhanced the ethanol yield up to 70% (w/w, theoretical) at a substrate concen- tration of 20% (w/v) by metabolising fermentation inhibitors

    Low-Prandtl-number B\'enard-Marangoni convection in a vertical magnetic field

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    The effect of a homogeneous magnetic field on surface-tension-driven B\'{e}nard convection is studied by means of direct numerical simulations. The flow is computed in a rectangular domain with periodic horizontal boundary conditions and the free-slip condition on the bottom wall using a pseudospectral Fourier-Chebyshev discretization. Deformations of the free surface are neglected. Two- and three-dimensional flows are computed for either vanishing or small Prandtl number, which are typical of liquid metals. The main focus of the paper is on a qualitative comparison of the flow states with the non-magnetic case, and on the effects associated with the possible near-cancellation of the nonlinear and pressure terms in the momentum equations for two-dimensional rolls. In the three-dimensional case, the transition from a stationary hexagonal pattern at the onset of convection to three-dimensional time-dependent convection is explored by a series of simulations at zero Prandtl number.Comment: 26 pages, 9 figure

    Gluon Condensates, Chiral Symmetry Breaking and Pion Wave Function

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    We consider here chiral symmetry breaking in quantum chromodynamics arising from gluon condensates in vacuum. Through coherent states of gluons simulating a mean field type of approximation, we show that the off-shell gluon condensates of vacuum generate a mass-like contribution for the quarks, giving rise to chiral symmetry breaking. We next note that spontaneous breaking of global chiral symmetry links the four component quark field operator to the pion wave function. This in turn yields many hadronic properties in the light quark sector in agreement with experiments, leading to the conclusion that low energy hadron properties are primarily driven by the vacuum structure of quantum chromodynamics.Comment: 25 pages, IP/BBSR/92-76, revte

    Body Fixed Frame, Rigid Gauge Rotations and Large N Random Fields in QCD

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    The "body fixed frame" with respect to local gauge transformations is introduced. Rigid gauge "rotations" in QCD and their \Sch equation are studied for static and dynamic quarks. Possible choices of the rigid gauge field configuration corresponding to a nonvanishing static colormagnetic field in the "body fixed" frame are discussed. A gauge invariant variational equation is derived in this frame. For large number N of colors the rigid gauge field configuration is regarded as random with maximally random probability distribution under constraints on macroscopic--like quantities. For the uniform magnetic field the joint probability distribution of the field components is determined by maximizing the appropriate entropy under the area law constraint for the Wilson loop. In the quark sector the gauge invariance requires the rigid gauge field configuration to appear not only as a background but also as inducing an instantaneous quark-quark interaction. Both are random in the large N limit.Comment: 29 pages LATEX, Weizmann Institute preprint WIS-93/40/Apr -P

    Effects of Pore Walls and Randomness on Phase Transitions in Porous Media

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    We study spin models within the mean field approximation to elucidate the topology of the phase diagrams of systems modeling the liquid-vapor transition and the separation of He3^3--He4^4 mixtures in periodic porous media. These topologies are found to be identical to those of the corresponding random field and random anisotropy spin systems with a bimodal distribution of the randomness. Our results suggest that the presence of walls (periodic or otherwise) are a key factor determining the nature of the phase diagram in porous media.Comment: REVTeX, 11 eps figures, to appear in Phys. Rev.

    Family history of mood disorder and characteristics of major depressive disorder: A STAR*D (sequenced treatment alternatives to relieve depression) study

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    Wstęp. Klinicyści rutynowo pytają pacjentów z depresją o występowanie chorób psychicznych w rodzinie. Nie wiadomo jednak, czy pacjenci, w których rodzinie występowały tego typu schorzenia różnią się od osób z negatywnym wywiadem rodzinnym w tym kierunku. W badaniu porównano cechy demograficzne i kliniczne dużej grupy pacjentów ambulatoryjnych zgłaszających się do lekarza z powodu depresji bez objawów psychotycznych. Pacjenci udzielili informacji na temat krewnych pierwszego stopnia chorujących na depresję lub chorobę afektywną dwubiegunową. Metody. Osoby poddane badaniu rekrutowano do wieloośrodkowego badania klinicznego - Sekwencyjne Alternatywy Terapeutyczne w Leczeniu Depresji (STAR*D, Sequenced Treatment Alternatives to Relieve Depression). Oceniono różnice w cechach klinicznych i demograficznych u pacjentów z dodatnim i ujemnym wywiadem rodzinnym w kierunku zaburzeń afektywnych, po skorygowaniu ich pod względem wieku, płci, rasy i grupy etnicznej. Wyniki. Wśród pacjentów z dodatnim wywiadem rodzinnym w kierunku zaburzeń afektywnych (n = 2265; 56,5%) przeważały kobiety; depresja rozpoczęła się u nich wcześniej niż u pacjentów z ujemnym wywiadem rodzinnym w kierunku zaburzeń afektywnych (n = 1740; 43,5%). Nie znaleziono znaczących różnic w zakresie objawów depresyjnych, nasilenia depresji, jej nawrotowości, podtypów choroby, czy też funkcjonowania w ciągu dnia. Wnioski. Kobiety 2-krotnie częściej niż mężczyźni zgłaszały występowanie zaburzeń afektywnych w rodzinie, dodatni wywiad rodzinny wiązał się z wcześniejszym wystąpieniem choroby u probanta. Młody wiek w chwili zachorowania na depresję wydaje się charakteryzować rodzinny (a co za tym idzie uwarunkowany genetycznie) podtyp depresji, co jest zgodne z wynikami wcześniejszych badań.Introduction. Clinicians routinely ask patients with major depressive disorder (MDD) about their family history. It is unknown, however, if patients who report a positive family history differ from those who do not. This study compared the demographic and clinical features of a large cohort of treatment-seeking outpatients with nonpsychotic MDD who reported that they did or did not have at least one firstdegree relative who had either MDD or bipolar disorder. Methods. Subjects were recruited for the STAR*D multicenter trial. Differences in demographic and clinical features for patients with and without a family history of mood disorders were assessed after correcting for age, sex, race, and ethnicity. Results. Patients with a family history of mood disorder (n = 2265; 56.5%) were more frequently women and had an earlier age of onset of depression, as compared to those without such a history (n = 1740; 43.5%). No meaningful differences were found in depressive symptoms, severity, recurrence, depressive subtype, or daily function. Conclusions. Women were twice as likely as men to report a positive family history of mood disorder, and a positive family history was associated with younger age of onset of MDD in the proband. Consistent with prior research, early age of onset appears to define a familial and, by extension, genetic subtype of major depressive disorder

    Colonialism, postcolonialism and the liberal welfare state

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    This article addresses the colonial and racial origins of the welfare state with a particular emphasis on the liberal welfare state of the USA and UK. Both are understood in terms of the centrality of the commodified status of labour power expressing a logic of market relations. In contrast, we argue that with a proper understanding of the relations of capitalism and colonialism, the sale of labour power as a commodity already represents a movement away from the commodified form of labour represented by enslavement. European colonialism is integral to the development of welfare states and their forms of inclusion and exclusion which remain racialised through into the twenty-first century

    Cell biological analysis reveals an essential role for Pfcerli2 in erythrocyte invasion by malaria parasites

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    Merozoite invasion of host red blood cells (RBCs) is essential for survival of the human malaria parasite Plasmodium falciparum. Proteins involved with RBC binding and invasion are secreted from dual-club shaped organelles at the apical tip of the merozoite called the rhoptries. Here we characterise P. falciparum Cytosolically Exposed Rhoptry Leaflet Interacting protein 2 (PfCERLI2), as a rhoptry bulb protein that is essential for merozoite invasion. Phylogenetic analyses show that cerli2 arose through an ancestral gene duplication of cerli1. We show that PfCERLI2 is essential for blood-stage growth and localises to the cytosolic face of the rhoptry bulb. Inducible knockdown of PfCERLI2 led to a proportion of merozoites failing to invade and was associated with elongation of the rhoptry organelle during merozoite development and inhibition of rhoptry antigen processing. These findings identify PfCERLI2 as a protein that has key roles in rhoptry biology during merozoite invasion.Benjamin Liffner, Juan Miguel Balbin, Gerald J. Shami, Ghizal Siddiqui, Jan Strauss, Sonja Frölich, Gary K. Heinemann, Ella May Edwards, Arne Alder, Jan Stephan Wichers, Darren J. Creek, Leann Tilley, Matthew W.A. Dixon, Tim-Wolf Gilberger, Danny W. Wilso

    The Idea of Social Life

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    This paper reclaims the idea that human society is a form of life, an idea once vibrant in the work of Toennies, Durkheim, Simmel, Le Bon, Kroeber, Freud, Bion, and Follett but moribund today. Despite current disparagements, this idea remains the only and best answer to our primary experience of society as vital feeling. The main obstacle to conceiving society as a life is linguistic; the logical form of life is incommensurate with the logical form of language. However, it is possible to extend our conceptual reach by appealing to alternative symbolisms more congenial to living form such as, and especially, art.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68336/2/10.1177_004839319502500201.pd
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