Théorie de l’information et diagnostic médical : une analyse coût-efficacité

Dans cet article, nous appliquons au domaine médical les principes de la théorie de l’information et nous montrons comment on peut l’utiliser pour sélectionner dans l’ensemble des stratégies diagnostiques possibles celles qui sont coût-efficaces.In this paper, we apply the principles of information theory to medical diagnosis and we show how it can be used to select cost-efficient diagnostic strategies in the set of feasible ones

Three km Track Time Trial Performance Changes after HIIT in Competitive Cross-Country Skiers

Background: Limited research surrounding sex differences in fatigue and performance after high intensity interval training (HIIT) exists in the field setting. While lab-based protocols provide a controlled environment, physiological mechanisms of fatigue and performance response in competitive athletes are best measured by time-trial (TT). Few studies, however, have investigated fatigue in TT performance while controlling for the menstrual cycle (MC). Objective: The study investigated the influence of sex and MC phase on 3km track TT performance after a HIIT session in Competitive Cross Country (XC) skiers. Methods: A quasi-experimental design was employed and athletes over the age of 16 years (30F, 9M), were recruited from across Canada and completed 3 days of testing/training: a 3km track TT on Day 1 and Day 3; and a HIIT session (4-8x, 800m) on Day 2. MC phase was verified by ovulation testing and salivary hormone samples; athletes were classified as either “Low Hormone” or “High Hormone” for analysis. Results: An overall improvement in performance from pre- to post-HIIT TTs occurred (p<0.01). No significant differences in TT performance after HIIT were observed between sexes (p=0.16) or MC phase (p=0.26). Conclusion: These results indicate that competitive XC skiers will likely experience an improvement in TT performance after a bout of HIIT. Coaches and athletes should plan their workouts prior to testing accordingly to maximize TT performance. These results also suggest that no special adjustments need to be considered for differences in performance after HIIT between sexes and MC phase, although further studies with a greater sample size and repeated testing are warranted

Combining metabolic flux analysis with proteomics to shed light on the metabolic flexibility: the case of Desulfovibrio vulgaris Hildenborough

IntroductionDesulfovibrio vulgaris Hildenborough is a gram-negative anaerobic bacterium belonging to the sulfate-reducing bacteria that exhibits highly versatile metabolism. By switching from one energy mode to another depending on nutrients availability in the environments„ it plays a central role in shaping ecosystems. Despite intensive efforts to study D. vulgaris energy metabolism at the genomic, biochemical and ecological level, bioenergetics in this microorganism remain far from being fully understood. Alternatively, metabolic modeling is a powerful tool to understand bioenergetics. However, all the current models for D. vulgaris appeared to be not easily adaptable to various environmental conditions.MethodsTo lift off these limitations, here we constructed a novel transparent and robust metabolic model to explain D. vulgaris bioenergetics by combining whole-cell proteomic analysis with modeling approaches (Flux Balance Analysis).ResultsThe iDvu71 model showed over 0.95 correlation with experimental data. Further simulations allowed a detailed description of D. vulgaris metabolism in various conditions of growth. Altogether, the simulations run in this study highlighted the sulfate-to-lactate consumption ratio as a pivotal factor in D. vulgaris energy metabolism.DiscussionIn particular, the impact on the hydrogen/formate balance and biomass synthesis is discussed. Overall, this study provides a novel insight into D. vulgaris metabolic flexibility

Complementary and alternative medicine use in glioma patients in France

PURPOSE Complementary and alternative medicine (CAM) use increases in cancer patients, including adult patients with diffuse gliomas. METHODS Questionnaires addressing CAM use were distributed to adult patients with gliomas of WHO grades II-IV and ECOG performance score of 0-2 during hospital visits and filled in anonymously. The study was conducted in nine centers in France from May 2017 to May 2018. Descriptive cohort analyses and comparative analyses according to gender, age, WHO grade, and recurrent versus newly diagnosed disease were conducted. RESULTS Two hundred twenty-seven questionnaires were collected; 135 patients (59%) were male. Median age was 48 years, 105 patients (46%) declared having glioblastoma, 99 patients (43%) declared having recurrent disease. Hundred-three patients (45%) had modified their alimentary habits after the glioma diagnosis. At the time of the questionnaire, 100 patients (44%) were on complementary treatment, mainly vitamins and food supplements, and 73 patients (32%) used alternative medicine approaches, mainly magnetism and acupuncture. In total, 154 patients (68%) declared using at least one of these approaches. Expenditures exceeding 100 € per month were reported by users in 14% for modification of alimentary habits, in 25% for complementary treatment, and in 18% for alternative medicines. All approaches were commonly considered as improving quality of life and experienced as efficient, notably those associated with more expenditures. CONCLUSIONS CAM are frequently used by glioma patients in France. Underlying needs and expectations, as well as potential interactions with tumor-specific treatments, and financial and quality of life burden, should be discussed with patients and caregivers

Twistor Approach to String Compactifications: a Review

We review a progress in obtaining the complete non-perturbative effective action of type II string theory compactified on a Calabi-Yau manifold. This problem is equivalent to understanding quantum corrections to the metric on the hypermultiplet moduli space. We show how all these corrections, which include D-brane and NS5-brane instantons, are incorporated in the framework of the twistor approach, which provides a powerful mathematical description of hyperkahler and quaternion-Kahler manifolds. We also present new insights on S-duality, quantum mirror symmetry, connections to integrable models and topological strings.Comment: 99 pages; minor corrections; journal versio

[C7GC4]4 Association into supra molecular i-motif structures

The self-associative properties of cytidine-rich oligonucleotides into symmetrical i-motif tetramers give to these oligonucleotides the capacity of forming supramolecular structures (sms) that have potential applications in the nanotechnology domain. In order to facilitate sms formation, oligonucleotides containing two cytidine stretches of unequal length (CnXCm) separated by a non-cytidine spacer were synthesized. They were designed to associate into a tetramer including an i-motif core built by intercalation of the C·C+ pairs of the longer C stretch with the two dangling non-intercalated strands of the shorter C stretch at each end. Gel filtration chromatography shows that the non-intercalated C-rich ends give to this structure the capacity of forming extremely stable sms. Using C7GC4 as a model, we find that the sms formation rate varies as the oligonucleotide concentration and increases at high temperature. Competitively with the tetramer involved in sms elongation, CnXCm oligonucleotides form i-motif dimers that compete with sms elongation. The dimer stability is strongly reduced when the pH is moved away from the cytidine pK. This results in an equilibrium shift towards the tetramer and in the acceleration of the sms formation rate. The chromatograms of the sms formed by C7GC4 indicate a broad distribution. In a 1.5 mM solution incubated at 37°C, the equilibrium distribution is centered on a molecular weight corresponding to the assembly of nine tetramers and the upper limit corresponds to 80 tetramers. The lifetime of this structure is about 4 days at 40°C, pH 4.6

Influencia de la metodología en los profesores que imparten la asignatura de Educación Física en el aprendizaje de la técnica del salto de longitud en los estudiantes de sexto año de educación básica

La presente investigación surge como una necesidad de los estudiantes de sexto año de educación básica que presentan dificultades en el aprendizaje de la técnica del salto de longitud, lo que la incido negativamente en el desarrollo motriz la que tiene como título: INFLUENCIA DE LA METODOLOGIA QUE UTILIZAN LOS PROFESORES QUE IMPARTEN LA ASIGNATURA DE EDUCACIÓN FÍSICA EN EL APRENDIZAJE DE LA TÉCNICA DEL SALTO DE LONGITUD EN LOS ESTUDIANTES DE SEXTO GRADO. Para la realización de la investigación la autora se formuló se formuló el siguiente objetivo. determinar la influencia de la metodología de la enseñanza que utilizan los docentes que imparten la asignatura en el aprendizaje motriz en la técnica del salto de longitud en los estudiantes de sexto grado de Educación Básica de la Escuela “Cinco de Junio” del Cantón Alfredo Baquerizo Moreno, durante el año lectivo 2014 – 2015? Para dar cumplimiento al objetivo antes mencionado se seleccionaron los siguientes métodos de investigación analítico – sintético, inductivo – deductivo, histórico – lógico , observación y test pedagógicos para el procesamiento estadístico de la información de los datos obtenidos se utilizó el cálculo porcentual (%), lo que permitió procesar la información mediante el análisis de los resultados obtenidos en los instrumentos aplicados a los 30 estudiantes que fueron escogidos como muestra. Los resultados obtenidos en la investigación permiten afirmar que la hipótesis es aceptada, ya que como se ha evidenciado durante el desarrollo del mismo, La metodología de la enseñanza que utilizan los profesores que imparten la asignatura de Educación Física incidió negativamente en el aprendizaje motriz de los estudiantes de sexto año de básica que fueron investigado

Compton Large Area Silicon Timing Tracker for Cosmic Vision M3

International audienceProposed in response to the ESA call for the third Medium size mission (M3), CAPSiTT is a small mission designed for a 3-year survey of the non-thermal high energy sky from an equatorial LEO orbit. With a large effective area and a very wide field of view, its single instrument, a silicon tracker, provides good imaging, spectroscopic and polarimetric capabilities with a sensitivity 10-100 times better than COMPTEL. Nucleosynthesis and particle acceleration mechanisms in various sites are the main scientific topics addressed by CAPSiTT