Strong local optimality for a bang-bang-singular extremal: the fixed-free case

International audienceIn this paper we give sufficient conditions for a Pontryagin extremal trajectory, consisting of two bang arcs followed by a partially or totally singular one, to be a strong local minimizer for a Mayer problem. The problem is defined on R n and the end-points constraints are of fixed-free type. We use a Hamiltonian approach and its connection with the second order conditions in the form of a LQ accessory problem. An example is proposed. All the results are coordinate free so they also hold on a manifold

Constrained bang-bang-singular extremals

International audienceBy means of Hamiltonian methods we give sufficient conditions for the strong local optimality of a Pontryagin extremal for a Mayer problem where both the end points of admissible trajectories are constrained to smooth manifolds of the state space. The extremal is given by the concatenation of two bang arcs and a partially singular one. Our sufficient conditions amount to regularity conditions on the extremal and the coercivity of a suitable quadratic form

Sufficient optimality conditions for a bang--singular extremal in the minimum time problem

The paper gives second order sufficient conditions for the strong local optimality of a bang-singular extremal in a minimum time problem. The conditions are given in terms of regularity assumptions on the extremal and of the coercivity of the extended second variation associated to the minimum time problem with fixed end-points on the singular arc. The conditions are close to the necessary ones in the usual sense, namely we require strict inequalities where necessary conditions have mild inequalities

clinical application of 2d speckle tracking strain for assessing cardio toxicity in oncology

Echocardiography has recently undergone innovations due to the availability of deformation parameters as strain, strain rate, torsion and rotation that allow an accurate assessment of myocardial function. Because of this general progress, the importance of myocardial deformation parameters has been highlighted, and some aspects of their clinical and research applications have recently been considered for the daily management of many acute and chronic metabolic diseases. The deformation parameters are largely proposed for the early detection of myocardial dysfunction, especially in the case of patients being completely asymptomatic. Strain analysis is extensively applied to cardiomyopathies, to coronary artery disease, or to the evaluation of the "forgotten chambers", such as the right ventricles and atria. More recently, several other clinical contexts, like non-communicable chronic diseases (NCCD), have actually been benefitting from specific evaluation by strain analysis. Lately, some specific aspects of strain evaluation, particularly Global Longitudinal Strain (GLS) have been shown to provide useful information of clinical relevance in the case of cancer patients. This paper presents an initial review of the recent applications of strain analysis in cardio-oncology, in order to share the recent experience in this field and to support the role of these parameters in cardio-oncology

Lifestyle Intervention in Surviving Cancer Patients

Supervised physical exercise and diet are normally suggested for preventing eventual weight gain, especially in cancer patients. However, little data is available on the effects of “unsupervised” mixed exercises associated with simple correct nutritional advice. This study aims to assess the impact of these two aspects in reducing major risk factors. 37 surviving cancer patients including breast (20 females) and colon cancer patients (10 males and seven females), aged 55.51 ± 10.94, were enrolled in this study on the correction of lifestyle habits. After six months from the onset of the study, the anthropometric parameters of Body Mass Index (BMI), circumference of waist/hip and also cardiovascular parameters (heart rate, blood pressure and respiratory rate during the 6 Minute Walking Test (6MWT) were measured. The resistance program was established using the Sit and Reach, Hand Grip and Chair Test. The anthropometric data showed significant modifications of the main parameters (body density T0: 1013.54 ± 10.48 g/cm3, T6: 1015 ± 10.45 g/cm3, p < 0.03; Fat Mass (FM%) T0: 38.44% ± 5.04%, T6: 37.65% ± 5.00%, p < 0.03; FFM% (Free Fat Mass) T0: 61.56% ± 5.04%, T6: 62.35% ± 5.00%, p < 0.03; TBW% (Total Body Water) T0: 49.26% ± 7.22%, T6: 47.94% ± 5.97%, p < 0.05). The respiratory rate decreased significantly (T0: 31.15 ± 4.61 bpm, T6: 29.42 ± 3.34 bpm, p < 0.04). The functional parameters, evaluated by the number of repetitions of the Chair Test, showed significant improvement (Chair Test T0: 13.20 ± 4.84 at rest, T6: 15.31 ± 3.54 at rest, p < 0.01). Moderate aerobic resistance unsupervised exercises, associated with correct nutritional habits, allow a significant improvement of the principal cardiovascular risk factors in cancer

Relationship between Protein Oxidation Biomarkers and Uterine Health in Dairy Cows during the Postpartum Period

High neutrophil (PMN, Polymorphonuclear neutrophil) counts in the endometrium of cows affected by endometritis, suggests the involvement of oxidative stress (OS) among the causes of impaired fertility. Protein oxidation, in particular, advanced oxidation protein products (AOPP), are OS biomarkers linked to PMN activity. To test this hypothesis, the relationship between protein oxidation and uterus health was studied in thirty-eight dairy cows during the puerperium. The animals were found to be cycling, without any signs of disease and pharmacological treatments. PMN count was performed either through a cytobrush or a uterine horn lavage (UHL). Cows were classified into four groups, based on the uterine ultrasonographic characteristics and the PMN percentage in the uterine horns with a higher percentage of high neutrophil horn (HNH). They were classified as: Healthy (H); Subclinical Endometritis (SCE); Grade 1 Endometritis (EM1); and Grade 2 Endometritis (EM2). AOPP and carbonyls were measured in plasma and UHL. UHL samples underwent Western blot analysis to visualize the carbonyl and dityrosine formation. Plasma AOPP were higher (p < 0.05) in EM2. AOPP and carbonyl group concentrations were higher in the HNH samples (p < 0.05). Protein concentration in the UHL was higher in the EM2 (p < 0.05). Carbonyl and dityrosine formation was more intense in EM1 and EM2. Protein oxidation observed in the EM2 suggests the presence of an inflammatory status in the uterus which, if not adequately hindered, could result in low fertility