News : 1/11 / Center for Financial Studies

Research and Policy 3 ; CFS Publications 3 ; CFS Financial Center Index 10 ; Events 12 ; CFS Visitors Program 12 ; CFS Colloquium 13 ; CFS Lectures 14 ; The Deutsche Bank Prize in Financial Economics 22 ; The ECB and Its Watchers 25 ; News from CFS 2

A lexicographic multi-objective genetic algorithm for multi-label correlation-based feature selection

This paper proposes a new Lexicographic multi-objective Genetic Algorithm for Multi-Label Correlation-based Feature Selection (LexGA-ML-CFS), which is an extension of the previous single-objective Genetic Algorithm for Multi-label Correlation-based Feature Selection (GA-ML-CFS). This extension uses a LexGA as a global search method for generating candidate feature subsets. In our experiments, we compare the results obtained by LexGA-ML-CFS with the results obtained by the original hill climbing-based ML-CFS, the single-objective GA-ML-CFS and a baseline Binary Relevance method, using ML-kNN as the multi-label classifier. The results from our experiments show that LexGA-ML-CFS improved predictive accuracy, by comparison with other methods, in some cases, but in general there was no statistically significant different between the results of LexGA-ML-CFS and other methods

Physiological cost of walking in those with chronic fatigue syndrome

<b>Purpose:</b> To examine the physiological cost of walking in subjects with chronic fatigue syndrome (CFS) and a matched control group, walking at their preferred and at matched walking speeds. <b>Methods:</b> Seventeen people with CFS and 17 matched-controls participated in this observational study of physiological cost during over-ground gait. Each subject walked for 5 min at their preferred walking speed (PWS). Controls then walked for 5 min at the same pace of their matched CFS subject. Gait speed and oxygen uptake, gross and net were measured and oxygen uptake was expressed per unit distance ambulated. CFS subjects completed the CFS-Activities and Participation Questionnaire (CFS-APQ). <b>Results:</b> At PWS the CFS group walked at a slower velocity of 0.84 ± 0.21 m s<sup>-1</sup> compared to controls with a velocity of 1.19 ± 0.13 m s<sup>-1</sup> (p < 0.001). At PWS both gross and net oxygen uptake of CFS subjects was significantly less than controls (p = 0.023 and p = 0.025 respectively). At matched-velocity both gross and net physiological cost of gait was greater for CFS subjects than controls (p = 0.048 and p = 0.001, respectively). <b>Conclusion:</b> The physiological cost of walking was significantly greater for people with CFS compared with healthy subjects. The reasons for these higher energy demands for walking in those with CFS have yet to be fully elucidated

Discriminating between chronic fatigue syndrome and depression: a cognitive analysis

Background: chronic fatigue syndrome (CFS) and depression share a number of common symptoms and the majority of CFS patients meet lifetime criteria for depression. While cognitive factors seem key to the maintenance of CFS and depression, little is known about how the cognitive characteristics differ in the two conditions.Methods: fifty-three CFS patients were compared with 20 depressed patients and 38 healthy controls on perceptions of their health, illness attributions, self-esteem, cognitive distortions of general and somatic events, symptoms of distress and coping. A 6 month follow-up was also conducted to determine the stability of these factors and to investigate whether CFS-related cognitions predict ongoing disability and fatigue in this disorder.Results: between-group analyses confirmed that the depressed group was distinguished by low self-esteem, the propensity to make cognitive distortions across all situations, and to attribute their illness to psychological factors. In contrast, the CFS patients were characterized by low ratings of their current health status, a strong illness identity, external attributions for their illness, and distortions in thinking that were specific to somatic experiences. They were also more likely than depressed patients to cope with their illness by limiting stress and activity levels. These CFS-related cognitions and behaviours were associated with disability and fatigue 6 months later.Conclusions: CFS and depression can be distinguished by unique cognitive styles characteristic of each condition. The documented cognitive profile of the CFS patients provides support for the current cognitive behavioural models of the illness

Chronic fatigue syndrome; an approach combining self-management with graded exercise to avoid exacerbations.

Controversy regarding the aetiology and treatment of patients with chronic fatigue syndrome (CFS) continues to affect the medical professions. The Cochrane collaboration advises practitioners to implement graded exercise therapy for CFS sufferers using cognitive behavioural principles. In contrast there is evidence that exercise can induce symptom exacerbations in CFS where too vigorous exercise/activity promotes immune dysfunction, which in turn increases symptoms in patients with CFS. When designing and implementing an exercise programme it is important to be aware of both these seemingly opposing view points in order to deliver a programme without any detrimental effects on CFS pathophysiology. Using evidence from both the biological and clinical sciences, the present manuscript explains that graded exercise therapy for people with CFS can be safely undertaken without detrimental effects to the immune system. Exercise programs should be designed to cater for individual physical capabilities and should also account for the fluctuating nature of symptoms commonly reported by people with CFS. In line with cognitive behaviourally and graded exercise-based strategies, self-management for people with CFS involves encouraging the patients to pace their activities and respect their physical and mental limitations with the ultimate aim of improving their everyday function

Equilibration of quantum hall edge states and its conductance fluctuations in graphene p-n junctions

We report an observation of conductance fuctuations (CFs) in the bipolar regime of quantum hall (QH) plateaus in graphene (p-n-p/n-p-n) devices. The CFs in the bipolar regime are shown to decrease with increasing bias and temperature. At high temperature (above 7 K) the CFs vanishes completely and the flat quantized plateaus are recovered in the bipolar regime. The values of QH plateaus are in theoretical agreement based on full equilibration of chiral channels at the p-n junction. The amplitude of CFs for different filling factors follows a trend predicted by the random matrix theory. Although, there are mismatch in the values of CFs between the experiment and theory but at higher filling factors the experimental values become closer to the theoretical prediction. The suppression of CFs and its dependence has been understood in terms of time dependent disorders present at the p-n junctions

Strong Magnetization Measured in the Cool Cores of Galaxy Clusters

Tangential discontinuities, seen as X-ray edges known as cold fronts (CFs), are ubiquitous in cool-core galaxy clusters. We analyze all 17 deprojected CF thermal profiles found in the literature, including three new CFs we tentatively identify (in clusters A2204 and 2A0335). We discover small but significant thermal pressure drops below all nonmerger CFs, and argue that they arise from strong magnetic fields below and parallel to the discontinuity, carrying 10%-20% of the pressure. Such magnetization can stabilize the CFs, and explain the CF-radio minihalo connection.Comment: PRL accepted, additional control tests adde

Reduced heart rate variability predicts fatigue severity in individuals with chronic fatigue syndrome/myalgic encephalomyelitis

Heart rate variability (HRV) is an objective, non-invasive tool to assessing autonomic dysfunction in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). People with CFS/ME tend to have lower HRV; however, in the literature there are only a few previous studies (most of them inconclusive) on their association with illness-related complaints. To address this issue, we assessed the value of different diurnal HRV parameters as potential biomarker in CFS/ME and also investigated the relationship between these HRV indices and self-reported symptoms in individuals with CFS/ME.Peer ReviewedPostprint (published version