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21.
Fingolimod, an oral sphingosine 1-phosphate (S1P) receptor modulator, is approved for the treatment of relapsing forms of multiple sclerosis (MS). The interference with S1P signaling leads to retention particularly of chemokine receptor-7 (CCR7) expressing T cells in lymph nodes. The immunological basis of varicella zoster virus (VZV) infections during fingolimod treatment is unclear. Here, we studied the dynamics of systemic and intrathecal immune responses associated with symptomatic VZV reactivation including cessation of fingolimod and initiation of antiviral therapy. Key features in peripheral blood were an about two-fold increase of VZV-specific IgG at diagnosis of VZV reactivation as compared to the previous months, a relative enrichment of effector CD4+ T cells (36% versus mean 12% in controls), and an accelerated reconstitution of absolute lymphocytes counts including a normalized CD4+/CD8+ ratio and reappearance of CCR7+ T cells. In cerebrospinal fluid (CSF) the lymphocytic pleocytosis and CD4+/CD8+ ratios at diagnosis of reactivation and after nine days of fingolimod discontinuation remained unchanged. During this time CCR7+ T cells were not observed in CSF. Further research into fingolimod-associated VZV reactivation and immune reconstitution is mandatory to prevent morbidity and mortality associated with this potentially life-threatening condition.  相似文献   
22.
Eugen Fischer 《连接科学》2018,30(2):211-243
Analogical reasoning is often employed in problem-solving and metaphor interpretation. This paper submits that, as a default, analogical reasoning addressing these different tasks employs different mapping strategies. In problem-solving, it employs analogy-maximising strategies (like structure mapping, Gentner, D., & Markman, A. B. (1997). Structure mapping in analogy and similarity. American Psychologist, 52, 45–56); in metaphor interpretation, analogy-minimising strategies (like ATT-Meta, Barnden, J. A. (2015). Open-ended elaborations in creative metaphor. In T. R. Besold, M. Schorlemmer, & A. Smaill (Eds.), Computational creativity research: Towards creative machines (pp. 217–242). Berlin: Springer). The two strategies interact in analogical reasoning with conceptual metaphors. This interaction leads to predictable fallacies. The paper supports these hypotheses through case-studies on “mind” metaphors from ordinary discourse, and abstract problem-solving in the philosophy of mind, respectively. It shows that (1) default metaphorical interpretations for vision- and space-cognition metaphors can be derived with a variant of the analogy-minimising ATT-Meta approach, (2) philosophically influential introspective conceptions of the mind can be derived with conceptual metaphors only through an analogy-maximising strategy, and (3) the interaction of these strategies leads to hitherto unrecognised fallacies in analogical reasoning with metaphors. This yields a debunking explanation of introspective conceptions.  相似文献   
23.
Based on a cascaded Kalman–Particle Filtering, gyroscope drift and robot attitude estimation method is proposed in this paper. Due to noisy and erroneous measurements of MEMS gyroscope, it is combined with Photogrammetry based vision navigation scenario. Quaternions kinematics and robot angular velocity dynamics with augmented drift dynamics of gyroscope are employed as system state space model. Nonlinear attitude kinematics, drift and robot angular movement dynamics each in 3 dimensions result in a nonlinear high dimensional system. To reduce the complexity, we propose a decomposition of system to cascaded subsystems and then design separate cascaded observers. This design leads to an easier tuning and more precise debugging from the perspective of programming and such a setting is well suited for a cooperative modular system with noticeably reduced computation time. Kalman Filtering (KF) is employed for the linear and Gaussian subsystem consisting of angular velocity and drift dynamics together with gyroscope measurement. The estimated angular velocity is utilized as input of the second Particle Filtering (PF) based observer in two scenarios of stochastic and deterministic inputs. Simulation results are provided to show the efficiency of the proposed method. Moreover, the experimental results based on data from a 3D MEMS IMU and a 3D camera system are used to demonstrate the efficiency of the method.  相似文献   
24.
We consider the problem of finding short strings that contain all permutations of order k over an alphabet of size n, with k?n. We show constructively that k(n−2)+3 is an upper bound on the length of shortest such strings, for n?k?10. Consequently, for n?10, the shortest strings that contain all permutations of order n have length at most n2−2n+3. These two new upper bounds improve with one unit the previous known upper bounds.  相似文献   
25.
In this paper we are investigating the magnetic behavior of the double-layer thin film in the extended Heisenberg model, with long-range dipolar interaction, taking into account the influence of the randomly distributed vacancies on the magnetic properties of the system. We are studying the physical quantities of interest (magnetization, magnetic susceptibility and specific heat) via Monte Carlo technique, by applying the standard Metropolis algorithm. In this context, we investigate the critical temperature variation for different vacancies concentration levels, taking into account the uniform and the superficial distribution of the defects, respectively.   相似文献   
26.
The numerical modeling of the conjugate heat transfer and fluid flow through the micro-tube was presented in the paper, considering the viscous dissipation effect. Three different fluids with temperature dependent fluid properties are considered: water and two dielectric fluids, HFE-7600 and FC-70. The diameter ratio of the micro-tube was Di/Do = 0.1/0.3 mm with a tube length L = 100 mm. The laminar fluid flow regime is analyzed. Two different heat transfer conditions are considered: heating and cooling and three different Br = 0.01, 0.1 and 0.5. The influence of the viscous heating on Nu and Po is analyzed and compared with Br = 0.  相似文献   
27.
In the present paper,the effect of variable fluid properties(density,viscosity,thermal conductivity and specific heat) on the convection in the classical Rayleigh-Bénard problem is investigated.The investigation concerns water,air,and engine oil by taking into account the variation of fluid properties with temperature.The results are obtained by numerically solving the governing equations,using the SIMPLE algorithm and covering large temperature differences.It is found that the critical Rayleigh number incr...  相似文献   
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The tensile fatigue behaviour of ultra-high performance fibre reinforced concrete (UHPFRC) under constant amplitude fatigue cycles is presented. Three series of uniaxial tensile fatigue tests up to a maximum of 10 million cycles were conducted with the objective to determine the endurance limit of UHPFRC that was supposed to exist for this material. The fatigue tests reveal that an endurance limit exists in all three domains of UHPFRC tensile behaviour at S-ratios ranging from 0.70 to 0.45 with S being the ratio of the maximum fatigue stress to the elastic limit strength of UHPFRC. Rather large variation in local specimen deformations indicates significant stress and deformation redistribution capacity of the UHPFRC bulk material enhancing the fatigue behaviour. The fatigue fracture surface of UHPFRC shows features of the fatigue fracture surfaces of steel, i.e. fatigue crack propagation is identified by a smooth surface while final fracture leads to rather rough surface. Various fatigue damaging mechanisms due to fretting and grinding as well as tribocorrosion are identified.  相似文献   
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