2,107 research outputs found

    Classical study of rotational excitation of a rigid rotor: Li+ plus H2

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    Classical trajectory study of rotationally inelastic scattering of hydrogen molecules by collisions with lithium ion

    Quantum mechanical study of molecules - Eigenvalues and eigenvectors of real symmetric matrices

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    Computer methods for calculating eigenvalue and eigenvectors of real symmetric matrices arising in problems of molecular quantum mechanic

    Molecular collisions. 16: Comparison of GPS with classical trajectory calculations of rotational inelasticity for the Ar-N2 system

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    Comparison of generalized phase shift treatment with classical trajectory calculations of rotational inelasticity cross sections of Ar-N2 scatterin

    Nova Geminorum 1912 and the Origin of the Idea of Gravitational Lensing

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    Einstein's early calculations of gravitational lensing, contained in a scratch notebook and dated to the spring of 1912, are reexamined. A hitherto unknown letter by Einstein suggests that he entertained the idea of explaining the phenomenon of new stars by gravitational lensing in the fall of 1915 much more seriously than was previously assumed. A reexamination of the relevant calculations by Einstein shows that, indeed, at least some of them most likely date from early October 1915. But in support of earlier historical interpretation of Einstein's notes, it is argued that the appearance of Nova Geminorum 1912 (DN Gem) in March 1912 may, in fact, provide a relevant context and motivation for Einstein's lensing calculations on the occasion of his first meeting with Erwin Freundlich during a visit in Berlin in April 1912. We also comment on the significance of Einstein's consideration of gravitational lensing in the fall of 1915 for the reconstruction of Einstein's final steps in his path towards general relativity.Comment: 31 p

    Pea leaf mitochondrial pyruvate dehydrogenase complex is inactivated in vivo in a light-dependent manner.

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    A compositional semantics for Repairable Fault Trees with general distributions

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    Fault Tree Analysis (FTA) is a prominent technique in industrial and scientific risk assessment. Repairable Fault Trees (RFT) enhance the classical Fault Tree (FT) model by introducing the possibility to describe complex dependent repairs of system components. Usual frameworks for analyzing FTs such as BDD, SBDD, and Markov chains fail to assess the desired properties over RFT complex models, either because these become too large, or due to cyclic behaviour introduced by dependent repairs. Simulation is another way to carry out this kind of analysis. In this paper we review the RFT model with Repair Boxes as introduced by Daniele Codetta-Raiteri. We present compositional semantics for this model in terms of Input/Output Stochastic Automata, which allows for the modelling of events occurring according to general continuous distribution. Moreover, we prove that the semantics generates (weakly) deterministic models, hence suitable for discrete event simulation, and prominently for Rare Event Simulation using the FIG tool

    Multiplicative noise: A mechanism leading to nonextensive statistical mechanics

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    A large variety of microscopic or mesoscopic models lead to generic results that accommodate naturally within Boltzmann-Gibbs statistical mechanics (based on S1kdup(u)lnp(u)S_1\equiv -k \int du p(u) \ln p(u)). Similarly, other classes of models point toward nonextensive statistical mechanics (based on Sqk[1du[p(u)]q]/[q1]S_q \equiv k [1-\int du [p(u)]^q]/[q-1], where the value of the entropic index qq\in\Re depends on the specific model). We show here a family of models, with multiplicative noise, which belongs to the nonextensive class. More specifically, we consider Langevin equations of the type u˙=f(u)+g(u)ξ(t)+η(t)\dot{u}=f(u)+g(u)\xi(t)+\eta(t), where ξ(t)\xi(t) and η(t)\eta(t) are independent zero-mean Gaussian white noises with respective amplitudes MM and AA. This leads to the Fokker-Planck equation tP(u,t)=u[f(u)P(u,t)]+Mu{g(u)u[g(u)P(u,t)]}+AuuP(u,t)\partial_t P(u,t) = -\partial_u[f(u) P(u,t)] + M\partial_u\{g(u)\partial_u[g(u)P(u,t)]\} + A\partial_{uu}P(u,t). Whenever the deterministic drift is proportional to the noise induced one, i.e., f(u)=τg(u)g(u)f(u) =-\tau g(u) g'(u), the stationary solution is shown to be P(u,){1(1q)β[g(u)]2}11qP(u, \infty) \propto \bigl\{1-(1-q) \beta [g(u)]^2 \bigr\}^{\frac{1}{1-q}} (with qτ+3Mτ+Mq \equiv \frac{\tau + 3M}{\tau+M} and β=τ+M2A\beta=\frac{\tau+M}{2A}). This distribution is precisely the one optimizing SqS_q with the constraint q{du[g(u)]2[P(u)]q}/{du[P(u)]q}=_q \equiv \{\int du [g(u)]^2[P(u)]^q \}/ \{\int du [P(u)]^q \}= constant. We also introduce and discuss various characterizations of the width of the distributions.Comment: 3 PS figure

    Immunosuppressant drugs and quality-of-life outcomes in kidney transplant recipients: An international cohort study (EU-TRAIN)

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    Immunosuppressant; Quality of life; TransplantationImmunosupressor; Qualitat de vida; TrasplantamentInmunosupresor; Calidad de vida; TrasplanteIntroduction: Patient-Reported Outcomes (PRO) integrate a wide range of holistic dimensions that arenot captured within clinical outcomes. Particularly, from induction treatment to maintenance therapy, patient quality-of-life (QoL) of kidney transplant recipients have been sparsely investigated in international settings. Methods: In a prospective, multi-centric cohort study, including nine transplant centers in four countries, we explored the QoL during the year following transplantation using validated elicitation instruments (EQ-5D-3L index with VAS) in a population of kidney transplant patients receiving immunosuppressive therapies. Calcineurin inhibitors (tacrolimus and ciclosporin), IMPD inhibitor (mycophenolate mofetil), and mTOR inhibitors (everolimus and sirolimus) were the standard-of-care (SOC) medications, together with tapering glucocorticoid therapy. We used EQ-5D and VAS data as QoL measures alongside descriptive statistics at inclusion, per country and hospital center. We computed the proportions of patients with different immunosuppressive therapy patterns, and using bivariate and multivariate analyses, assessed the variations of EQ-5D and VAS between baseline (i.e., inclusion Month 0) and follow up visits (Month 12). Results: Among 542 kidney transplant patients included and followed from November 2018 to June 2021, 491 filled at least one QoL questionnaire at least at baseline (Month 0). The majority of patients in all countries received tacrolimus and mycophenolate mofetil, ranging from 90.0% in Switzerland and Spain to 95.8% in Germany. At M12, a significant proportion of patients switched immunosuppressive drugs, with proportion varying from 20% in Germany to 40% in Spain and Switzerland. At visit M12, patients who kept SOC therapy had higher EQ-5D (by 8 percentage points, p < 0.05) and VAS (by 4 percentage points, p < 0.1) scores than switchers. VAS scores were generally lower than EQ-5D (mean 0.68 [0.5–0.8] vs. 0.85 [0.8–1]). Discussion: Although overall a positive trend in QoL was observed, the formal analyses did not show any significant improvements in EQ-5D scores or VAS. Only when the effect of a therapy use was separated from the effect of switching, the VAS score was significantly worse for switchers during the follow up period, irrespective of the therapy type. If adjusted for patient characteristics and medical history (e.g., gender, BMI, eGRF, history of diabetes), VAS and EQ-5D delivered sound PRO measures for QoL assessments during the year following renal transplantation.The project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 754995. Open access funding by University of Lausanne
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