110 research outputs found

    Parakinesia: A Delphi consensus report.

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    Abnormal movements are intrinsic to some forms of endogenous psychoses. Spontaneous dyskinesias are observed in drug-naïve first-episode patients and at-risk subjects. However, recent descriptions of spontaneous dyskinesias may actually represent the rediscovery of a more complex phenomenon, 'parakinesia' which was described and documented in extensive cinematographic recordings and long-term observations by German and French neuropsychiatrists decades before the introduction of antipsychotics. With the emergence of drug induced movement disorders, the description of parakinesia has been refined to emphasize the features enabling differential diagnosis with tardive dyskinesia. Unfortunately, parakinesia was largely neglected by mainstream psychiatry to the point of being almost absent from the English-language literature. With the renewed interest in motor phenomena intrinsic to SSD, it was timely not only to raise awareness of parakinesia, but also to propose a scientifically usable definition for this phenomenon. Therefore, we conducted a Delphi consensus exercise with clinicians familiar with the concept of parakinesia. The original concept was separated into hyperkinetic parakinesia (HPk) as dyskinetic-like expressive movements and parakinetic psychomotricity (PPM), i.e., patient's departing from the patient's normal motion style. HPk prevails on the upper part of the face and body, resembling expressive and reactive gestures that not only occur inappropriately but also appear distorted. Abnormal movements vary in intensity depending on the level of psychomotor arousal and are thus abated by antipsychotics. HPk frequently co-occurs with PPM, in which gestures and mimics lose their naturalness and become awkward, disharmonious, stiff, mannered, and bizarre. Patients are never spontaneously aware of HPk or PPM, and the movements are never experienced as self-dystonic or self-alien. HPk and PPM are highly specific to endogenous psychoses, in which they are acquired and progressive, giving them prognostic value. Their differential diagnoses and correspondences with current international concepts are discussed

    Surface Correction Control Based on Plasticized Multilayer P(VDF‐TrFE‐CFE) Actuator—Live Mirror

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    International audienceThe interdisciplinary approach presented here creates next‐generation large mirrors using electroactive polymer (EAP) actuators without classical glass abrasive polishing (“live mirrors”). The outstanding electromechanical coupling properties of terpolymer are taken advantage of, particularly when doped with plasticizer, e.g., diisononyl phthalate (DINP). This doped terpolymer creates a large strain response as well as excellent mechanical energy density under relatively low electric fields. Classical EAPs (e.g., polyurethane, silicone) require extremely high input voltages to reach sufficient mechanical strain. Using the high‐permittivity doped terpolymer and the concept of stacking multilayers, high displacements and large forces are generated. The actuation performance of multilayered terpolymer filled with DINP has been proven to shape mirror glass with a preliminary prototype of an 8‐layer actuator stack. The experimental results demonstrate surface deformations under load conditions of several microns. This is large enough to usefully control large optical telescope mirrors. This technology may enable much larger high‐quality optical mirror systems for ground‐ and space‐based astronomy and communications telescopes

    Solitonic metrics and harmonic maps

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    We investigate the relationship between solitonic metrics gu=(sin2u/2)c2dt2+(cos2u/2)sumi=1n(dxi)2g_u= - (sin^2 u/2 ) c^2 dt^2 + (cos^2 u/2 ) sum_{i=1}^n (d x^i)^2 with uinCinfty(mathbbRn+1)u in C^infty ( mathbb{R}^{n+1} ) and stationary points of the functional EOmega(Phi)=(1/2)intOmegadPhi2dn+1mathbfxE_Omega ( Phi ) = (1/2) int_Omega || d Phi ||^2 d^{n+1} mathbf{x} with PhiinCinfty(mathbbRn+1,S2)Phi in C^infty (mathbb{R}^{n+1} , S^2). Building on work by F.L. Williams (cf. Williams, in: Milton (ed), Quantum field theory under the influence of external conditions, Rinton Press, Princeton, pp. 370–372, 2004; in: 4th International Winter Conference on Mathematical Methods in Physics, Rio de Janeiro, http://pos.sissa.it/archive/conferences/013/003/wc2004_003.pdf (http://pos.sissa.it/archive/conferences/013/003/wc2004_003.pdf), 2004; in: Chen (ed.), Trends in Soliton Research, Nova Science Publications, Hauppauge, pp. 1–14, 2006; in: Maraver, Kevrekidis, Williams (eds.), The sine-Gordon modeland its applications, Springer, Berlin, pp. 177–205, 2014) we show that a map Phi=(cosbetasinu/2,sinbetacosu/2)Phi = (cos beta sin u/2 , sin beta cos u/2 ) with beta(mathbfx,t)=m(1+mathbfv2)1/2(t+mathbfvcdotmathbfxbeta (mathbf{x} , t) = m (1 + | mathbf{v} |^2 )^{-1/2} (t + mathbf{v} cdot mathbf{x} is harmonic if and only if utt+Deltau=m2sinuu_{tt} + Delta u = m^2 sin u (the sine-Gordon equation) and ut+mathbfvcdotnablau=0u_t + mathbf{v} cdot nabla u = 0 (the convection equation). In the spirit of work by B. Solomon (cf. Solomon in J. Differ. Geom. 21:151–162, 1985) we build a 1-parameter variation of PhiPhi which singles out [from the full Euler–Lagrange system of the variational principle deltaEOmega(Phi)=0delta E_Omega (Phi)=0] the convection equation. Williams’ harmonic maps Phipm=(1+v2)1/2(taucosbeta,tausinbeta,pm(1+v2)1/2tanhrho)Phi^{pm} = ( 1 + v^2 )^{-1/2} ( tau cos beta , tau sin beta , pm (1+ v^2 )^{1/2} tanh rho ) are shown to be harmonic morphisms of dilation lambda=m(1+v2)1/2taulambda = m ( 1 + v^2 )^{-1/2} tau , further explaining the relationship between Jackiw–Teitelboim 2-dimensional dilation-gravity theory (cf. Jackiw, in: Christensen (ed), Quantum theory of gravity, MIT, Cambridge, pp. 403–420, 1982; Teitelboim, in: Christensen (ed), Quantum theory of gravity, Adam Hilger Ltd, Bristol, pp. 403–420, 1984) and harmonic map theory (cf. Baird and Wood, Harmonic morphisms between Riemannian manifolds, London Mathematical Society monographs, new series, 29, The Clarendon Press, Oxford University Press, Oxford, ISBN 0-19-850362-8, 2003). We show that geodesic motion in a weak solitonic gravitational field guepsilong_{u_epsilon} [ uepsilon=u0+2epsilonrhou_epsilon = u_0 + 2 epsilon rho with rhoinCinfty(mathbbRn+1)rho in C^infty (mathbb{R}^{n+1} ) bounded and epsilon <<1 ] in the Newtonian velocity limit ( ||mathbf{u} ||/c << 1) obeys to the law of motion d2mathbfr/dt2=nablaphid^2 mathbf{r}/ dt^2 = - nabla phi in a central force field of potential phiequivepsilonc2tan(u0/2)rhophi equiv epsilon c^2 tan (u_0/2) rho. To justify the use of geodesic equations as equations of motion we address a relativistic mechanics problem i.e. the rotation of a disc in a solitonic gravitational field and exhibit a class of metrics gug_u one of whose geodesic equations yields a relativistic generalization d2r/ds2=(rw2)/c2d^2 r/d s^2 = (r w^2)/c^2 of centrifugal accelerations in classical mechanics

    Transcatheter heart valve failure: a systematic review

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    Aims A comprehensive description of transcatheter heart valve (THV) failure has not been performed. We undertook a systematic review to investigate the aetiology, diagnosis, management, and outcomes of THV failure. Methods and results The systematic review was performed in accordance with the PRISMA guidelines using EMBASE, MEDLINE, and Scopus. Between December 2002 and March 2014, 70 publications reported 87 individual cases of transcatheter aortic valve implantation (TAVI) failure. Similar to surgical bioprosthetic heart valve failure, we observed cases of prosthetic valve endocarditis (PVE) (n = 34), structural valve failure (n = 13), and THV thrombosis (n = 15). The microbiological profile of THV PVE was similar to surgical PVE, though one-quarter had satellite mitral valve endocarditis, and surgical intervention was required in 40% (75% survival). Structural valve failure occurred most frequently due to leaflet calcification and was predominantly treated by redo-THV (60%). Transcatheter heart valve thrombosis occurred at a mean 9 +/- 7 months post-implantation and was successfully treated by prolonged anticoagulation in three-quarters of cases. Two novel causes of THV failure were identified: late THV embolization (n = 18); and THV compression (n = 7) following cardiopulmonary resuscitation (CPR). These failure modes have not been reported in the surgical literature. Potential risk factors for late THV embolization include low prosthesis implantation, THV undersizing/underexpansion, bicuspid, and non-calcified anatomy. Transcatheter heart valve embolization mandated surgery in 80% of patients. Transcatheter heart valve compression was noted at post-mortem in most cases. Conclusion Transcatheter heart valves are susceptible to failure modes typical to those of surgical bioprostheses and unique to their specific design. Transcatheter heart valve compression and late embolization represent complications previously unreported in the surgical literature

    Bezlotoxumab for Prevention of Recurrent Clostridium difficile Infection

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    BACKGROUND Clostridium difficile is the most common cause of infectious diarrhea in hospitalized patients. Recurrences are common after antibiotic therapy. Actoxumab and bezlotoxumab are human monoclonal antibodies against C. difficile toxins A and B, respectively. METHODS We conducted two double-blind, randomized, placebo-controlled, phase 3 trials, MODIFY I and MODIFY II, involving 2655 adults receiving oral standard-of-care antibiotics for primary or recurrent C. difficile infection. Participants received an infusion of bezlotoxumab (10 mg per kilogram of body weight), actoxumab plus bezlotoxumab (10 mg per kilogram each), or placebo; actoxumab alone (10 mg per kilogram) was given in MODIFY I but discontinued after a planned interim analysis. The primary end point was recurrent infection (new episode after initial clinical cure) within 12 weeks after infusion in the modified intention-to-treat population. RESULTS In both trials, the rate of recurrent C. difficile infection was significantly lower with bezlotoxumab alone than with placebo (MODIFY I: 17% [67 of 386] vs. 28% [109 of 395]; adjusted difference, −10.1 percentage points; 95% confidence interval [CI], −15.9 to −4.3; P<0.001; MODIFY II: 16% [62 of 395] vs. 26% [97 of 378]; adjusted difference, −9.9 percentage points; 95% CI, −15.5 to −4.3; P<0.001) and was significantly lower with actoxumab plus bezlotoxumab than with placebo (MODIFY I: 16% [61 of 383] vs. 28% [109 of 395]; adjusted difference, −11.6 percentage points; 95% CI, −17.4 to −5.9; P<0.001; MODIFY II: 15% [58 of 390] vs. 26% [97 of 378]; adjusted difference, −10.7 percentage points; 95% CI, −16.4 to −5.1; P<0.001). In prespecified subgroup analyses (combined data set), rates of recurrent infection were lower in both groups that received bezlotoxumab than in the placebo group in subpopulations at high risk for recurrent infection or for an adverse outcome. The rates of initial clinical cure were 80% with bezlotoxumab alone, 73% with actoxumab plus bezlotoxumab, and 80% with placebo; the rates of sustained cure (initial clinical cure without recurrent infection in 12 weeks) were 64%, 58%, and 54%, respectively. The rates of adverse events were similar among these groups; the most common events were diarrhea and nausea. CONCLUSIONS Among participants receiving antibiotic treatment for primary or recurrent C. difficile infection, bezlotoxumab was associated with a substantially lower rate of recurrent infection than placebo and had a safety profile similar to that of placebo. The addition of actoxumab did not improve efficacy. (Funded by Merck; MODIFY I and MODIFY II ClinicalTrials.gov numbers, NCT01241552 and NCT01513239.