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In these lectures, I pedagogically review some recent advances in the study of the non-equilibrium dynamics of isolated quantum systems. In particular I emphasise the role played by the reduced density matrix and by the entanglement entropy in the understanding of the stationary properties after a quantum quench. The idea that the stationary thermodynamic entropy is the entanglement accumulated during the non-equilibrium dynamics is introduced and used to provide quantitative predictions for the time evolution of the entanglement itself. The harmonic chain is studied as an elementary model in which the quench dynamics can be easily and exactly worked out. This example provides a useful playground where general concepts can be simply understood and later applied to more complex and realistic systems.

Introduction Physiotherapy may alleviate many multiple sclerosis (MS) symptoms, yet very little is known about physiotherapy accessibility and possible barriers in persons with MS (pwMS). We therefore aimed to elucidate physiotherapy use and possible access-barriers using data from 1493 pwMS from the Swiss Multiple Sclerosis Registry (SMSR), a patient-centered, longitudinal, observational MS study. Methods We used data of the SMSR to investigate the question at hand in a multivariable logistic regression model with regularly receiving physiotherapy (yes/no) as the outcome. Potential explanatory variables were investigated following an AIC-driven model selection approach and consisted of a priori specified socio-demographic variables, health status, and personal or social mobility variables. As a last step, the impact of physiotherapist supply on regular use was assessed in the final model. Missing data were handled by multiple imputation (main analysis), and complete case sensitivity analyses were performed. Results The main analysis included 1493 participants. In the multivariable logistic regression, positive associations were found between the use of physiotherapy and the following variables: having a primary-progressive MS (Odds Ratio (OR) [95% Confidence Intervals] 1.97 [1.18; 3.29]), being more severely impaired (EDSS 4-6.5 OR 1.84 [1.16; 2.91]), higher number of current symptoms (1 OR 3.31 [1.63; 6.74], 2-3 OR 3.43 [1.8; 6.53], 4-5 OR 4.44 [2.28; 8.66], 6-7 OR 4.06 [1.90; 8.70], 8-9 OR 3.87 [1.71; 8.75], being on disability pension (OR 1.75 [1.24; 2.46], or having applied for it OR 2.25 [1.31; 3.85]), having gait problems (OR 1.58 [1.11; 2.23]), having been in a rehabilitation clinic in the past 12 months (OR 4.43 [2.17; 9.03]), and currently being on disease-modifying treatment (OR 1.61 [1.12; 2.31]). Negative associations were found for a higher quality of life (OR 0.92 [0.85; 0.98]), working more than 80% (OR 0.47 [0.30; 0.75]) and being from the French language region (OR 0.66 [0.47; 0.94]). No association between physiotherapist supply and regular physiotherapy use was detected. Discussion In a large, Swiss-based MS population, little evidence for socio-demographic barriers to physical therapy was found. Physiotherapy uptake was higher among pwMS with more impairments, lower health-related quality of life, or who have been discharged recently from inpatient rehabilitation. The uptake differences by language region warrant further investigations., Multiple Sclerosis and Related Disorders, 48, ISSN:2211-0356, ISSN:2211-0348

Background Clinician-assessed Expanded Disease Status Scale (EDSS) is gold standard in clinical investigations but normally unavailable in population-based, patient-centred MS-studies. Our objective was to develop a self-reported gait measure reflecting EDSS-categories. Methods We developed the self-reported disability status scale (SRDSS) with three categories (≤3.5, 4–6.5, ≥7) based on three mobility-related questions. The SRDSS was determined for 173 persons with MS and validated against clinical EDSS to calculate sensitivity and specificity. Results Accuracy was 88.4% (153 correctly classified) and weighted kappa 0.73 (0.62–0.84). Sensitivity/specificity-pairs were 94.5%/77.8%, 69.0%/94.7% and 100%/98.2% for SRDSS ≤3.5, 4–6.5 and ≥7, respectively. Conclusions Self-reported SRDSS approximates EDSS-categories well and fosters comparability between clinical and population-based studies.

Introduction Cognitive impairment and depressive symptoms caused by Parkinson's disease (PD) are often underestimated in routine clinical practice, partly due to the lack of short screening tests. The "Parkinson Neuropsychometric Dementia Assessment" (PANDA) is a new convenient tool, validated in German, to assess cognition in PD. It consists of five cognitive tasks and a brief mood questionnaire, and is designed for the early detection of mild cognitive deficits as well as dementia. Aims To translate the PANDA into French and provide normative data for a French speaking population. Methods The translation was made by means of the translation/re-translation method. The normation was conducted with 61 control subjects (CS). The Mini Mental State Examination (MMSE) was administered concurrently. A comparison was made with the original study's control group (CG) to determine whether the German algorithms for converting the raw scores could also be used with the French version or whether a new procedure had to be developed. All statistics were conducted with SPSS Statistics18. Results There is a significant correlation between the PANDA total score and MMSE ( r =0.42, p =0.001). Analysis of the total converted scores shows no significant correlation with age ( r =−0.19; p =0.14). After correction for education, there is no significant difference between our CS and the original study's CG ( t =1.50; p =0.14). Conclusions Our results indicate that the PANDA French translation can be used with the same transformation algorithms as the German version, when adding a correction for education.

Cognitive and affective dysfunctions are frequent but often neglected symptoms in Parkinson’s disease (PD). We developed the screening tool Parkinson neuropsychometric dementia assessment (PANDA) with five cognitive tasks and a short depression questionnaire. Healthy subjects and patients without cognitive impairment (PD), mild cognitive disorder (PD-MCD), or dementia (PDD) were examined. The cognition part had a specificity of 91% and a sensitivity of 90% for PDD and 77% for PDD plus PD-MCD patients. The mood questionnaire also had high sensitivity and specificity. We conclude that the PANDA is an economical, easy-to-use and sensitive tool to detect neuropsychological dysfunctions in PD patients in clinical practice.

Background: Treatment-related neurotoxicity has been recognized as a significant problem in patients with primary central nervous system lymphoma (PCNSL) as effective treatment has increased survival rates. There is, however, a paucity of research on cognitive functions in this population. Design: In a review of the literature, a total of 17 articles that described cognitive outcome in adult PCNSL patients were identified. Results: The studies that assessed cognitive functions after whole-brain radiotherapy combined with chemotherapy reported cognitive impairment in most patients. Patients treated with chemotherapy alone had either stable or improved cognitive performance in most studies. Methodological problems, however, limited the ability to ascertain the specific contribution of disease and various treatment interventions to cognitive outcome. On the basis of the literature review, a battery of cognitive and quality-of-life (QoL) measures to be used in prospective clinical trials was proposed. The battery is composed of five standardized neuropsychological tests, covering four domains sensitive to disease and treatment effects (attention, executive functions, memory, psychomotor speed), and QoL questionnaires, and meets criteria for use in collaborative trials. Conclusion: The incorporation of formal and systematic cognitive evaluations in PCNSL studies will improve our understanding of treatment-related neurotoxicity in this population. © 2007 European Society for Medical Oncology.

We investigate the phase diagram and, in particular, the nature of the the multicritical point in three-dimensional frustrated $N$-component spin models with noncollinear order in the presence of an external field, for instance easy-axis stacked triangular antiferromagnets in the presence of a magnetic field along the easy axis. For this purpose we study the renormalization-group flow in a Landau-Ginzburg-Wilson \phi^4 theory with symmetry O(2)x[Z_2 +O(N-1)] that is expected to describe the multicritical behavior. We compute its MS \beta functions to five loops. For N\ge 4, their analysis does not support the hypothesis of an effective enlargement of the symmetry at the multicritical point, from O(2) x [Z_2+O(N-1)] to O(2)xO(N). For the physically interesting case N=3, the analysis does not allow us to exclude the corresponding symmetry enlargement controlled by the O(2)xO(3) fixed point. Moreover, it does not provide evidence for any other stable fixed point. Thus, on the basis of our field-theoretical results, the transition at the multicritical point is expected to be either continuous and controlled by the O(2)xO(3) fixed point or to be of first order., Comment: 28 pages, 3 figs

We compute the renormalization group functions of a Landau–Ginzburg–Wilson Hamiltonian with O(n)×O(m) symmetry up to five-loop in minimal subtraction scheme. The line n+(m,d), which limits the region of second-order phase transition, is reconstructed in the framework of the ϵ=4−d expansion for generic values of m up to O(ϵ5). For the physically interesting case of noncollinear but planar orderings (m=2) we obtain n+(2,3)=6.1(6) by exploiting different resummation procedures. We substantiate this results reanalyzing six-loop fixed dimension series with pseudo-ϵ expansion, obtaining n+(2,3)=6.22(12). We also provide predictions for the critical exponents characterizing the second-order phase transition occurring for n>n+.

The role of the fornix for episodic memory processing is still a matter of controversy. A juvenile patient of average post-surgical intelligence with fornical damage due to tumor removal is described. The fornix was damaged bilaterally at the level of the fornical columns. The patient thereafter suffered major anterograde amnesia which was most pronounced in tests using long delays (e.g., in the delayed recall index of the revised Wechsler Memory Scale). Amnesia was as prominent on the verbal as on the nonverbal level. Attention, concentration and short term memory abilities were preserved. Cognitive flexibility, procedural memory and priming were principally unimpaired. There was no evidence of retrograde amnesia. It is concluded that the fornix constitutes a major link between the three memory interfaces (medial diencephalon, medial temporal lobe, basal forebrain) and that its bilateral rupture anterior to the thalamic level may lead to lasting anterograde amnesia.