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International audience; In this article, we give an in-depth analysis of the problem of optimising the total population size for a standard logistic-diffusive model. This optimisation problem stems from the study of spatial ecology and amounts to the following question: assuming a species evolves in a domain, what is the best way to spread resources in order to ensure a maximal population size at equilibrium? {In recent years, many authors contributed to this topic.} We settle here the proof of two fundamental properties of optimisers: the bang-bang one which had so far only been proved under several strong assumptions, and the other one is the fragmentation of maximisers. Here, we prove the bang-bang property in all generality using a new spectral method. The technique introduced to demonstrate the bang-bang character of optimizers can be adapted and generalized to many optimization problems with other classes of bilinear optimal control problems where the state equation is semilinear and elliptic. We comment on it in a conclusion section.Regarding the geometry of maximisers, we exhibit a blow-up rate for the $BV$-norm of maximisers as the diffusivity gets smaller: if $\Omega$ is an orthotope and if $m_\mu$ is an optimal control, then $\Vert m_\mu\Vert_{BV}\gtrsim \sqrt{\mu}$. The proof of this results relies on a very fine energy argument.

Background: In Gabon, the epidemic of pulmonary tuberculosis (TB) in prisons is poorly documented. There is no official data, even though these environments meet the perfect conditions for transmission of the disease: overcrowding, close and prolonged contact, and the inexistence of a policy of screening/medical check-up of inmates upon their admission to prison. The objective of this study was to conduct a prospective and cross- sectional study to assess the prevalence of pulmonary tuberculosis in the prison environment of Yéné, the central prison of Franceville, capital of the Haut-Ogooué province. Methods: A preliminary clinical survey of inmates identified a cohort of 100 individuals suspected of having TB based on clinical symptoms. Subsequently, from June 9 to 13, 2022, we collected sputum samples from inmates suspected of having TB. These samples were analyzed by the molecular biology technique GeneXpert MTB/RIF.Conclusion: In Yéné prison, the non-existence of diagnostic tests for TB to newly incarcerated inmates puts other inmates as well as prison officers at risk for TB infection.

Patrick Leigh Fermor’s travel narrative A Time of Gifts stages the liminal condition of the future writer leaving England in 1933 and aiming to reach Constantinople on foot. As he crosses Central Europe his digressions into medieval, Renaissance and modern European history function as distorted mirrors to the present-day history of political hostility. Forcing us to adjust our focus through repeated forms of displacement, Fermor allows us to share the narrator’s vulnerable position and to embark on his quest for poetic, pictorial and historical fragments that spur us to look beyond “the long night ahead” (TG 357). Le récit de voyage de Patrick Leigh Fermor, A Time of Gifts, met en scène la situation fragile du futur écrivain quittant l’Angleterre en 1933 pour atteindre Constantinople à pied. Tout au long de sa traversée de l’Europe centrale, ses digressions sur le Moyen-Âge, la Renaissance et l’Histoire moderne européenne offrent un contrepoint aux politiques contemporaines marquées par l’hostilité. Fermor joue de multiples formes de déplacement pour partager avec ses lecteurs sa propre vulnérabilité et sa quête de fragments poétiques, picturaux et historiques qui nous entraîne au-delà de la « longue nuit qui approche » (TG 357).

We address the convergence of thresholding schemes for spectral optimisation problems and linear control problems.

International audience; Sterile Insect Technique is an autocidal method to control Vector of diseases and crop pest. It consists of releasing males sterilized by ionization, in a targeted area, that will mate with the wild females, resulting in a reduce, eventually a local elimination, of the wild population. However, migration of wild insects, from a non-targeted area, can be problematic and reduce the efficiency of SIT [1]. The control strategies should be adapted to take this issue into account. We consider a two patches system, where Patch 1 is the targeted area linked to another area, Patch 2, that needs not to be controlled. Wild and sterile insects can circulate between the two Patches, so that different issues have to be solved. Is it possible to find one or several strategies, and among them an optimal strategy, to reach elimination in patch 1? Should we control both patches? Using results related to monotone cooperative systems [2] and also tools from optimal control theory, we will show some theoretical responses [3]. We will also illustrate the theoretical results with numerical simulations and discuss the extension of our results.

(1) Background: Immunosuppression is a key barrier to effective anti-cancer therapies, particularly in triple-negative breast cancer (TNBC), an aggressive and difficult to treat form of breast cancer. We investigated here whether the combination of doxorubicin, a standard chemotherapy in TNBC with glyceryltrinitrate (GTN), a nitric oxide (NO) donor, could overcome chemotherapy resistance and highlight the mechanisms involved in a mouse model of TNBC. (2) Methods: Balb/C-bearing subcutaneous 4T1 (TNBC) tumors were treated with doxorubicin (8 mg/Kg) and GTN (5 mg/kg) and monitored for tumor growth and tumor-infiltrating immune cells. The effect of treatments on MDSCs reprogramming was investigated ex vivo and in vitro. (3) Results: GTN improved the anti-tumor efficacy of doxorubicin in TNBC tumors. This combination increases the intra-tumor recruitment and activation of CD8+ lymphocytes and dampens the immunosuppressive function of PMN-MDSCs PD-L1low. Mechanistically, in PMN-MDSC, the doxorubicin/GTN combination reduced STAT5 phosphorylation, while GTN +/− doxorubicin induced a ROS-dependent cleavage of STAT5 associated with a decrease in FATP2. (4) Conclusion: We have identified a new combination enhancing the immune-mediated anticancer therapy in a TNBC mouse model through the reprograming of PMN-MDSCs towards a less immunosuppressive phenotype. These findings prompt the testing of GTN combined with chemotherapies as an adjuvant in TNBC patients experiencing treatment failure.

Cette photographie de jeune rugbywoman interpelle parce qu’elle représente une guerrière appartenant au monde contemporain et qu’elle pose des enjeux passés, présents et à venir liés à l’esthétique et au politique. En effet, une sportive est encore aujourd’hui occupée à trouver sa juste place, laquelle n’est certainement pas sur le banc de touche ou au ban de la société, même pour un instant figé par l’image. De nombreuses dynamiques s’entrecroisent dans cette photographie, en particulier celles des regards. Certains s’échangent, certains possèdent, d’autres informent, enfin les plus radicaux mettent à distance l’observateur. Et ceux-là donnent la sensation que « la terre se met à trembler » parce qu’ils révèlent la limite de l’intolérable. Être une femme ne sera plus jamais un handicap ou une entrave à l’exercice du sport de haut niveau. This photograph of a young rugbywoman puzzles because it represents a warrior from the contemporary world and because it raises past, present and future issues related to aesthetics and politics. Indeed, sportswomen are still busy today finding their legitimate place, which is certainly not on the substitutes’ bench or on the sidelines of society... not even for an instant on a frozen picture. Numerous dynamics intertwine in this photograph, in particular those of the glances. Some are exchanged, some possess, others inform, and finally the most radical ones distance the observer. Those make you feel as if the earth were shaking because they reveal the limits of what is tolerable: being a woman will never again be a handicap or a hindrance to the practice of high-level sport.

“Mito”, “Andean Papaya” and “kerko” are the popular names of Vasconcellea candicans (A. Gray) A. DC. In some regions in Peru, this species is a shrub tree, endemic to the Peruvian Andes and Ecuador. This study aimed to evaluate the antioxidant and hypoglycemic effect of the ethanolic extract of Vasconcellea candicans fruit on alloxaninduced hyperglycemia in albino mice. Vasconcellea candicans fruits were collected in Uruiza, Lucanas-Ayacucho, Peru. Phytochemical analysis was carried out to confirm chemical groups, and antioxidant activity in vitro was measured using two methods, 2,2- diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonicacid) diammonium salt radical cation (ABTS). In the pharmacological evaluation, hyperglycemia was induced with alloxan using doses of 170 mg/kg in albino mice, animals with a glucose level of more than 250 mg/dL were included in the treatment. Animals were randomized into five groups (I: Alloxan 170 mg/kg; II, III, and IV: Vasconcellea candicans extract: 100, 300, and 500 mg/kg body weight; and V: glibenclamide 5 mg/kg). The phytochemical analysis confirmed the presence of flavonoids, alkaloids, terpenes, saponins, and phenolic compounds. It was observed that at doses of 100, 300, and 500 mg/kg, blood glucose was reduced by 43.6%, 60.8%, and 70.5 %, respectively, after 16 days of treatment. The ethanolic extract had an IC50 = 19.6±0.5 µg/mL and 5.05±0.01 µg/mL against DPPH and the ABTS radical, respectively. In conclusion, the ethanolic extract of the Vasconcellea candicans fruit was demonstrated to be effective at 500 mg/kg following 14 days of treatment in mice.

A primary goal in transplantation medicine is the induction of a tolerogenic environment for prevention of transplant rejection without the need for long-term pharmacological immunosuppression. Generation of alloantigen-specific regulatory T cells (Tregs) by transduction with chimeric antigen receptors (CARs) is a promising strategy to achieve this goal. This publication reports the preclinical characterization of Tregs (TR101) transduced with a human leukocyte antigen (HLA)-A*02 CAR lentiviral vector (TX200) designated to induce immunosuppression of allograft-specific effector T cells in HLA-A*02-negative recipients of HLA-A*02-positive transplants. In vitro results demonstrated specificity, immunosuppressive function, and safety of TX200-TR101. In NOD scid gamma (NSG) mice, TX200-TR101 prevented graft-versus-host disease (GvHD) in a xenogeneic GvHD model and TX200-TR101 Tregs localized to human HLA-A*02-positive skin transplants in a transplant model. TX200-TR101 persisted over the entire duration of a 3-month study in humanized HLA-A*02 NSG mice and remained stable, without switching to a proinflammatory phenotype. Concomitant tacrolimus did not impair TX200-TR101 Treg survival or their ability to inhibit peripheral blood mononuclear cell (PBMC) engraftment. These data demonstrate that TX200-TR101 is specific, stable, efficacious, and safe in preclinical models, and provide the basis for a first-in-human study.