Blow-up dynamics of self-attracting diffusive particles driven by competing convexities

In this paper, we analyze the dynamics of an $N$ particles system evolving according the gradient flow of an energy functional. The particle system is a consistent approximation of the Lagrangian formulation of a one parameter family of non-local drift-diffusion equations in one spatial dimension. We shall prove the global in time existence of the trajectories of the particles (under a sufficient condition on the initial distribution) and give two blow-up criteria. All these results are consequences of the competition between the discrete entropy and the discrete interaction energy. They are also consistent with the continuous setting, that in turn is a one dimension reformulation of the parabolic-elliptic Keller-Segel in high dimensions

Constituerend en geconstitueerd: Merleau-Ponty en de uitdrukking van Europese identiteit

De huidige constitutionele crisis van de Europese Unie vraagt de filosoof om een grondige herdenking van de grondslagen van recht en staat. Centraal hierbij staat de klassieke verhouding tussen constituerende en geconstitueerde macht. Traditioneel worden deze concepten strikt gescheiden. Democratietheorieën leren ons dat het soevereine volk de constituerende macht is en blijft, waaraan de geconstitueerde machten (wetgevend, uitvoerend en rechterlijk) ondergeschikt zijn. Merleau-Ponty geeft ons echter aanwijzingen om de verhouding tussen constituerende en geconstitueerde macht anders te denken, waardoor ook ons begrip van de constitutie van de juridische en politieke identiteit van Europa verandert. Zijn reflectie over de verhouding tussen parole parlante en parole parlée geeft ons een nieuwe blik op de constitutie van eenheid. Zo ook probeert Europa haar politieke eenheid elke keer weer opnieuw uit te drukken, maar slaagt hier nooit volledig in. Constituerende en geconstitueerde macht staan in een voortdurende spanningsverhouding met elkaar. Er is geen sprake van een dualisme, maar beide polen kunnen ook nooit samen vallen. Hierdoor is elke claim op eenheid uiteindelijk weerlegbaar. Dit is echter geen probleem, maar eerder een uitdaging aan de huidige Europese politiek en aan de politieke filosofie.Luigi Corrias studeerde Europees Recht en Wijsbegeerte aan de Universiteit van Tilburg (UvT). Sinds mei 2003 is hij als AIO verbonden aan de sectie rechtsfilosofie van de Faculteit der Wijsbegeerte van de UvT. Hij werkt aan een proefschrift over constituerende en geconstitueerde macht vanuit het perspectief van de filosofie van Merleau-Ponty

L p and L ∞ a priori estimates for some chemotaxis models and applications to the Cauchy problem

International audienceIn this note, we generalize some a priori estimates from our earlier work concerning two models of chemotaxis. We also give a new L ∞ bound for these models which yields uniqueness for one of them

Epidemiology and clinical aspect of mushroom poisonings in South Sardinia: A 10-year retrospective analysis (2011-2021)

Mushroom poisoning is a severe problem of public health, however, information about its epidemiology and management is still limited. This is the first study focused on Sardinia that investigates data about mushroom poisoning describing epidemiology, clinical presentation, seasonality, and the most common involved species. In this retrospective study, we analyzed data recovered from the database of Mycological Inspectorates during a 10-year period (2011-2021). Overall, 164 cases of mushroom poisoning have been identified, with significant peaks in autumn. The highest number of episodes of intoxication were recorded in Cagliari (64), followed by Carbonia (55) and Sanluri (45), although the annual distribution of cases among the provinces varied considerably in the study period. Thanks to the expertise of the Mycological Inspectorate service, the implicated species have been identified in 162 cases (98.78%); 81 cases were caused by toxic species, 60 by edible, and 45 by not edible species. Omphalotus olearius and Agaricus xanthodermus were the most represented toxic species (22% and 18%, respectively); Boletus aereus (18%) was the most frequent edible species, while Boletaceae were the prevalent not edible mushrooms. The data collected in South Sardinia over a period of 10-years demonstrate how a correct and rapid recognition of mushroom poisoning is important to improve the prognosis of patients, however, there are still problems of lack of knowledge, on the part of the population, on the existence of the consultancy services. Because most illnesses from poisonous mushroom ingestion are preventable, increased public awareness about the potential dangers of mushroom poisoning is mandatory

Heart applications of 4D flow

Four-dimensional (4D) flow sequences are an innovative type of MR sequences based upon phase contrast (PC) sequences which are a type of application of Angio-MRI together with the Time of Flight (TOF) sequences and Contrast-Enhanced Magnetic Resonance Acquisition (CE-MRA). They share the basic principles of PC, but unlike PC sequences, 4D flow has velocity encoding along all three flow directions and three-dimensional (3D) anatomic coverage. They guarantee the analysis of flow with multiplanarity on a post-processing level, which is a unique feature among MR sequences. Furthermore, this technique provides a completely new level to the in vivo flow analysis as it allows measurements in never studied districts such as intracranial applications or some parts of the heart never studied with echo-color-doppler, which is its sonographic equivalent. Furthermore, this technique provides a completely new level to the in vivo flow analysis as it allows accurate measurement of the flows in different districts (e.g., intracranial, cardiac) that are usually studied with echo-color-doppler, which is its sonographic equivalent. Of note, the technique has proved to be affected by less inter and intra-observer variability in several application. 4D-flow basic principles, advantages, limitations, common pitfalls and artefacts are described. This review will outline the basis of the formation of PC image, the construction of a 4D-flow and the huge impact the technique is having on the cardiovascular non-invasive examination. It will be then studied how this technique has had a huge impact on cardiovascular examinations especially on a central heart level

Influence of the MCT1 rs1049434 on Indirect Muscle Disorders/Injuries in Elite Football Players

The aim of this study was to investigate the association between MCT1 rs1049434 polymorphism and indirect muscle injuries in elite football players. One hundred and seventy-three male elite Italian football players (age = 19.2 ± 5.3 years) were recruited from a first-league football club participating at the Official National Italian Football Championship (Serie A, Primavera, Allievi, Giovanissimi). The cohort was genotyped for the MCT1 rs1049434 polymorphism, and muscle injuries data were collected during the period of 2009-2014 (five football seasons).Genomic DNA was extracted using a buccal swab, and genotyping was performed using PCR method. Structural-mechanical injuries and functional muscle disorder were included in the acute indirect muscle injury group.Participants with the MCT1 AA (AA = 1.57 ± 3.07, n = 69) genotype exhibit significantly higher injury incidents compared to participants with the TT genotype (TT = 0.09 ± 0.25, n = 22, P = 0.04).The MCT1 rs1049434 polymorphism is associated with the incidence of muscle injuries in elite football players. We anticipate that the knowledge of athletes' genetic predisposition to sports-related injuries might aid in individualizing training programs

Desafios no ensino da língua de herança: o italiano em Pedrinhas Paulista

Este artigo apresenta um estudo sobre o processo de implantação do ensino de italiano como língua de herança em Pedrinhas Paulista, uma ex-colônia italiana, e tem como foco os desafios encontrados durante as fases de planejamento do curso e de elaboração do material didático. Do ponto de vista teórico, a pesquisa apoia-se na Pedagogia Pós-Método e nos estudos sobre políticas linguísticas e línguas de herança. Os resultados preliminares apontam para a importância de criar espaços formais de aprendizagem da língua de herança e também da existência de políticas linguísticas familiares para a sua manutenção em contextos informais. O trabalho corrobora ainda, a ideia de que o ensino de língua de herança distingue-se do ensino de uma língua estrangeira, aponta as especificidades da revitalização linguística e cultural de comunidades após o processo de reterritorialização

A study of blow-ups in the Keller-Segel model of chemotaxis

We study the Keller-Segel model of chemotaxis and develop a composite particle-grid numerical method with adaptive time stepping which allows us to accurately resolve singular solutions. The numerical findings (in two dimensions) are then compared with analytical predictions regarding formation and interaction of singularities obtained via analysis of the stochastic differential equations associated with the Keller-Segel model

PD-L1 expression in metastatic neuroblastoma as an additional mechanism for limiting immune surveillance

The prognosis of high-risk neuroblastoma (NB) remains poor, although immunotherapies with anti-GD2 antibodies have been reported to provide some benefit. Immunotherapies can be associated with an IFNγ storm that induces in tumor cells the “adaptive immune resistance” characterized by the de-novo expression of Programmed Death Ligands (PD-Ls). Tumor cells can also constitutively express PD-Ls in response to oncogenic signaling. Here, we analyze the constitutive and the inducible surface expression of PD-Ls in NB cells. We show that virtually all HLA class Ipos NB cell lines constitutively express PD-L1, whereas PD-L2 is rarely detected. IFNγ upregulates or induces PD-L1 both in NB cell lines in vitro and in NB engrafted nude/nude mice. Importantly, after IFNγ stimulation PD-L1 can be acquired by NB cell lines, as well as by metastatic neuroblasts isolated from bone marrow aspirates of high-risk NB patients, characterized by different MYCN amplification status. Interestingly, in one patient NB cells were poorly responsive to IFNγ stimulation, pointing out that responsiveness to IFNγ might represent a further element of heterogeneity in metastatic neuroblasts. Finally, we document the presence of lymphocytes expressing the PD-1 receptor in NB-infiltrated bone marrow of patients. PD-1pos cells are mainly represented by αβ T cells, but also include small populations of γδ T cells and NK cells. Moreover, PD-1pos T cells have a higher expression of activation markers. Overall, our data show that a PD-L1-mediated immune resistance mechanism occurs in metastatic neuroblasts and provide a biological rationale for blocking the PD-1/PD-Ls axis in future combined immunotherapeutic approaches