Ground-state energy and excitation spectrum of the Lieb-Liniger model : accurate analytical results and conjectures about the exact solution

We study the ground-state properties and excitation spectrum of the Lieb-Liniger model, i.e. the one-dimensional Bose gas with repulsive contact interactions. We solve the Bethe-Ansatz equations in the thermodynamic limit by using an analytic method based on a series expansion on orthogonal polynomials developed in \cite{Ristivojevic} and push the expansion to an unprecedented order. By a careful analysis of the mathematical structure of the series expansion, we make a conjecture for the analytic exact result at zero temperature and show that the partially resummed expressions thereby obtained compete with accurate numerical calculations. This allows us to evaluate the density of quasi-momenta, the ground-state energy, the local two-body correlation function and Tan's contact. Then, we study the two branches of the excitation spectrum. Using a general analysis of their properties and symmetries, we obtain novel analytical expressions at arbitrary interaction strength which are found to be extremely accurate in a wide range of intermediate to strong interactions

Tan's contact of a harmonically trapped one-dimensional Bose gas: strong-coupling expansion and conjectural approach at arbitrary interactions

We study Tan's contact, i.e. the coefficient of the high-momentum tails of the momentum distribution at leading order, for an interacting one-dimensional Bose gas subjected to a harmonic confinement. Using a strong-coupling systematic expansion of the ground-state energy of the homogeneous system stemming from the Bethe-Ansatz solution, together with the local-density approximation, we obtain the strong-coupling expansion for Tan's contact of the harmonically trapped gas. Also, we use a very accurate conjecture for the ground-state energy of the homogeneous system to obtain an approximate expression for Tan's contact for arbitrary interaction strength, thus estimating the accuracy of the strong-coupling expansion. Our results are relevant for ongoing experiments with ultracold atomic gases

Dynamic structure factor and drag force in a one-dimensional strongly-interacting Bose gas at finite temperature

We study the effect of thermal and quantum fluctuations on the dynamical response of a one-dimensional strongly-interacting Bose gas in a tight atomic waveguide. We combine the Luttinger liquid theory at arbitrary interactions and the exact Bose-Fermi mapping in the Tonks-Girardeau-impenetrable-boson limit to obtain the dynamic structure factor of the strongly-interacting fluid at finite temperature. Then, we determine the drag force felt by a potential barrier moving along the fluid in the experimentally realistic situation of finite barrier width and temperature.Comment: 13 pages, 11 figure

A connection between non-local one-body and local three-body correlations of the Lieb-Liniger model

We derive a connection between the fourth coefficient of the short-distance Taylor expansion of the one-body correlation function, and the local three-body correlation function of the Lieb-Liniger model of $\delta$-interacting spinless bosons in one dimension. This connection, valid at arbitrary interaction strength, involves the fourth moment of the density of quasi-momenta. Generalizing recent conjectures, we propose approximate analytical expressions for the fourth coefficient covering the whole range of repulsive interactions, validated by comparison with accurate numerics. In particular, we find that the fourth coefficient changes sign at interaction strength $\gamma_c\simeq 3.816$, while the first three coefficients of the Taylor expansion of the one-body correlation function retain the same sign throughout the whole range of interaction strengths

Vinyl chloride-diet interactions in liver disease : potential roles of autophagy and energy management.

Vinyl chloride (VC) is a prevalent environmental toxicant that has been shown to cause liver injury at high, occupational exposures. However, most studies have not addressed interactions of low doses with risk-modifying factors. This study aims to explore low-level VC metabolite exposure interactions with other potential risk-modifying factors and their effect on underlying liver disease. We examined sub-hepatotoxic effects of a VC metabolite (chloroethanol, CE) in two murine models of liver injury using ethanol and lipopolysaccharide (LPS). In both, CE significantly enhanced liver injury when compared to either ethanol or LPS alone. Previous studies have shown an increase in mTOR activity with CE alone. Here, we used a pharmacologic inhibitor of mTOR, rapamycin, to study its effect on injury progression. Indeed, the addition of rapamycin significantly attenuated liver injury, hepatic steatosis, and inflammatory markers in the CE + LPS model

Vinyl chloride enhances diet-induced liver injury via metabolic dyshomeostasis : critical role of mitochondria.

Background. Vinyl chloride (VC) is an environmental toxicant and has been shown to be directly hepatotoxic at high exposures. However, recent studies suggest low-level toxicant exposure can cause subtle changes to the liver. Given the high prevalence of non-alcoholic fatty liver disease (NAFLD) in the United States, it is important to determine the impact of low-level toxicant exposure on the progression of underlying liver injury when combined with other factors. Therefore, the overarching goal of this dissertation was to develop a model of VC co-exposure with high-fat diet (HFD) and to determine the mechanisms by which VC contributes to the development of liver injury. Methods. Mice were fed a low fat diet (LFD) or high fat diet (HFD) and exposed to sub-OSHA levels of VC (0.85 ± 0.1 ppm) or room air 6 hours per day, 5 days per week, for either 6, 8, or 12 weeks. Metabolic phenotyping, biochemical and histological assessment of liver injury, indices for oxidative and endoplasmic reticulum (ER) stress, and mitochondrial function were examined for each time point. Results. Chapter III of this dissertation describes a VC inhalation model in which co-exposure to a HFD significantly enhances liver injury associated with NAFLD. Specifically, mice exposed to both VC and HFD had significantly enhanced indices of liver injury, inflammation, and cell death. In Chapter IV, metabolic dyshomeostasis is evaluated as a mechanism by which VC exposure sensitizes the liver to secondary insults. Indeed, mice exposed to VC alone had significant alterations in glucose homeostasis in addition to enhanced oxidative and ER stress. Finally, Chapter V examines the effect of VC exposure on mitochondrial integrity and function. Importantly, VC’s detrimental effect on mitochondria is specific to enzymes involved in oxidative phosphorylation, rather than general mito-toxic action. Discussion. In conclusion, the work presented in this dissertation has shown that sub-OHSA levels of VC exposure are sufficient to enhance underlying liver injury. Moreover, VC exposure can cause metabolic disruption even in combination with a LFD. VC directly targets complexes of oxidative respiration which sensitize hepatocytes to subsequent injury and cell death

ĝardeno paradizo

A collective project with a cultural, educational and landscaping focus co-curated by Anna Colin and Mécènes du Sud Montpellier-Sète-Béziers, in partnership with Habitat Jeunes Sète Bassin de Thau. Taking place throughout 2023, the project worked to rehabilitate the outdoor spaces of a young's people supported accommodation (Résidence Sévigné) in the city of Sète, France, turning it into a relational, well-being, and biodiverse space, putting art and design at the service of this space. It was developed with the following practitioners: Tiphaine Calmettes (artist), Louis Danjou (artist, chef), Aude Mohammedi-Merquiol (producer, horticulturist), Mr. & Mr. (designers, architects, educators) and Lisa Ouakil (artist), working in close collaboration with the young people of Résidence Sévigné

Estrogens: Two nuclear receptors, multiple possibilities

Much is known about estrogen action in experimental animal models and in human physiology. This article reviews the mechanisms of estrogen activity in animals and humans and the role of its two receptors α and β in terms of structure and mechanisms of action in various tissues in health and in relationship with human pathologies (e.g., osteoporosis). Recently, the spectrum of clinical pictures of estrogen resistance caused by estrogen receptors gene variants has been widened by our description of a woman with β-receptor defect, which could be added to the already known descriptions of α-receptor defect in women and men and β-receptor defect in men. The essential role of the β-receptor in the development of the gonad stands out. We summarize the clinical pictures due to estrogen resistance in men and women and focus on long-term follow-up of two women, one with α- and the other with β-receptor resistance. Some open questions remain on the complex interactions between the two receptors on bone metabolism and hypothalamus-pituitary-gonadal axis, which need further deepening and research