Active and structural lesions of the sacro-iliac joints in spondyloarthritis

MRI gains importance in early diagnosis of spondyloarthritis as it detects active inflammatory and structural lesions well before radiographic changes become evident. A ‘positive’ MRI with bone marrow oedema of the sacro-iliac joint is a key criterion in current disease classification systems

Entanglement Entropy, decoherence, and quantum phase transition of a dissipative two-level system

The concept of entanglement entropy appears in multiple contexts, from black hole physics to quantum information theory, where it measures the entanglement of quantum states. We investigate the entanglement entropy in a simple model, the spin-boson model, which describes a qubit (two-level system) interacting with a collection of harmonic oscillators that models the environment responsible for decoherence and dissipation. The entanglement entropy allows to make a precise unification between entanglement of the spin with its environment, decoherence, and quantum phase transitions. We derive exact analytical results which are confirmed by Numerical Renormalization Group arguments both for an ohmic and a subohmic bosonic bath. Those demonstrate that the entanglement entropy obeys universal scalings. We make comparisons with entanglement properties in the quantum Ising model and in the Dicke model. We also emphasize the possibility of measuring this entanglement entropy using charge qubits subject to electromagnetic noise; such measurements would provide an empirical proof of the existence of entanglement entropy.Comment: 38 pages, 8 figures, related to cond-mat/0612095 and arXiv:0705.0957; final version to appear in Annals of Physic

Étude qualitative des stratégies de prise en charge utilisées par les masseurs-kinésithérapeutes salariés et libéraux diplômés d’État pour obtenir l’adhésion thérapeutique des adolescents atteints de mucoviscidose

Advances in management of Cystic fibrosis pathology have improved quality of life for patients to the detriment of more complicated treatment. It is responsible for a decrease in motivation leading to occurrence of non-adhesion factors, especially for teenager cases. The aim of this study is to identify the tools used by salaried and liberal physiotherapists to get adolescent therapeutic adherence to his own care. This qualitative study is a survey carried out by means of semi-directional interviews with 8 liberal or staff physiotherapists in order to obtain right feedback on experience and to identify their beliefs about therapeutic adherence. Strategies and tools used by physiotherapists to evaluate and assess motivation in order to get adolescent involvement in care and increase therapeutic adherence are mainly oral exchange, therapeutic education, physical activity, video games as well as organizational means. The use of these tools depends on the interviewee’s salary or liberal status. The quality of the carecare relationship, family support and interdisciplinarity have been identified as factors of therapeutic adherence. The results of the study underline the importance for physiotherapists to have a therapeutic arsenal of motivational tools to treat problems of adherence to care. This brief opens ways to thinking of use of these tools for other chronic pathologies, use of new technologies for motivation as well as on the patient adherence’s impact due to different care according to the physiotherapist status.Les progrès dans la prise en charge de la mucoviscidose ont permis d’améliorer la qualité de vie des patients au prix d’un traitement plus complexe. Celui-ci est à l’origine d’une diminution de la motivation entrainant l’apparition de facteurs de non-adhésion, notamment chez les adolescents. L’objectif de cette étude est d’identifier les stratégies de prise en charge utilisées par les masseurs-kinésithérapeutes salariés et libéraux pour obtenir l’adhésion thérapeutique de l’adolescent à ses soins. Cette étude qualitative est une enquête réalisée au moyen d’entretiens semi-directifs auprès de 8 masseurs-kinésithérapeutes, salariés et libéraux afin d’avoir un retour d’expérience et d’identifier leur croyances sur l’adhésion thérapeutique. Les stratégies de prise en charge utilisées par les masseurs-kinésithérapeutes pour évaluer la motivation et motiver les adolescents à suivre leurs soins afin d’obtenir l’adhésion thérapeutique sont : l’échange oral, l’éducation thérapeutique, l’activité physique, les jeux vidéo ainsi que des moyens organisationnels. L’usage de ces outils dépend du statut salarial ou libéral de l’interviewé. La qualité de la relation soignant-soigné, le soutien familial et l’interdisciplinarité ont été relevés comme étant des facteurs d’adhésion thérapeutique. Les résultats de l’étude soulignent l’importance pour les masseurs-kinésithérapeutes d’avoir un arsenal thérapeutique d’outils motivationnels pour traiter des problématiques d’adhésion aux soins. Ce mémoire ouvre des pistes de réflexion sur l’utilisation de ces outils pour d’autres pathologies chroniques, sur l’utilisation des nouvelles technologies au service de la motivation ainsi que sur l’impact d’une différence de prise en charge selon le statut du masseur-kinésithérapeute sur l’adhésion du patient

On the evaluation of different procedures for computing aerodynamic loads for the unsteady vortex lattice method

The unsteady vortex-lattice method (UVLM) is widely used to estimate the aerodynamic loads for unsteady subsonic flows. The approach is well-suited for applications where the free-wake modeling becomes critical, for example hovering rotors, wind turbine blades, flapping wings and flexible aircraft. Several procedures have been proposed in the literature for computing aerodynamic loads for the UVLM. In this paper we present a comparative evaluation among three such techniques: the Joukowski method, the Katz method and a modified version of the Katz method developed at Virginia Tech. The methodology used to evaluate the quality of the predictions of the aforementioned methods consists in a convergence analysis of the aerodynamic loads (lift and induced drag) for a lifting surface undergoing pitching and plunging motions. In addition, the authors provide: i) a detailed description of the theoret- ical aspects of each one of the methods; ii) a detailed description of the computational implementation; and iii) a detailed analysis of the computational cost. All methods are implemented in a single Fortran code. The numerical results obtained using the code present good agreement with known solutions found in the literature for two-dimensional airfoils and three-dimensional wings in steady and unsteady flows cases

Non-Thyroidal Illness Syndrome in Critically Ill Children: Prognostic Value and Impact of Nutritional Management

INTRODUCTION: Non-thyroidal illness (NTI), which occurs with fasting and in response to illness, is characterized by thyroid hormone inactivation with low triiodothyronine (T3) and high reverse T3 (rT3), followed by suppressed thyrotropin (TSH). Withholding supplemental parenteral nutrition early in pediatric critical illness (late-PN), thus accepting low/no macronutrient intake up to day 8 in the pediatric intensive care unit (PICU), accelerated recovery compared to initiating supplemental parenteral nutrition early (early-PN). Whether NTI is harmful or beneficial in pediatric critical illness and how it is affected by a macronutrient deficit remains unclear. This study investigated the prognostic value of NTI, the impact of late-PN on NTI, and whether such impact explains or counteracts the outcome benefit of late-PN in critically ill children. METHODS: This preplanned secondary analysis of the Early versus Late Parenteral Nutrition in the Pediatric Intensive Care Unit randomized controlled trial quantified serum TSH, total thyroxine (T4), T3, and rT3 concentrations in 982 patients upon PICU admission versus 64 matched healthy children and in 772 propensity score-matched early-PN and late-PN patients upon admission and at day 3 or last PICU day for shorter PICU stay. Associations between thyroid hormone concentrations upon admission and outcome, as well as impact of late-PN on NTI in relation with outcome, were assessed with univariable analyses and multivariable logistic regression, linear regression, or Cox proportional hazard analysis, adjusted for baseline risk factors. RESULTS: Upon PICU admission, critically ill children revealed lower TSH, T4, T3, and T3/rT3 and higher rT3 than healthy children (p < 0.0001). A more pronounced NTI upon admission, with low T4, T3, and T3/rT3 and high rT3 was associated with higher mortality and morbidity. Late-PN further reduced T4, T3, and T3/rT3 and increased rT3 (p ≤ 0.001). Statistically, the further lowering of T4 by late-PN reduced the outcome benefit (p < 0.0001), whereas the further lowering of T3/rT3 explained part of the outcome benefit of late-PN (p ≤ 0.004). This effect was greater for infants than for older children. CONCLUSION: In critically ill children, the peripheral inactivation of thyroid hormone, characterized by a decrease in T3/rT3, which is further accentuated by low/no macronutrient intake, appears beneficial. In contrast, the central component of NTI attributable to suppressed TSH, evidenced by the decrease in T4, seems to be a harmful response to critical illness. Whether treating the central component with TSH releasing hormone infusion in the PICU is beneficial requires further investigation.status: publishe