2,089 research outputs found
Global estimates for nonlinear parabolic equations
We consider nonlinear parabolic equations of the type under standard growth
conditions on , with only assumed to be integrable. We prove general
decay estimates up to the boundary for level sets of the solutions and the
gradient which imply very general estimates in Lebesgue and Lorentz
spaces. Assuming only that the involved domains satisfy a mild exterior
capacity density condition, we provide global regularity results.Comment: To appear in J. Evol. Equation
Local behavior of fractional -minimizers
We extend the De Giorgi-Nash-Moser theory to nonlocal, possibly degenerate
integro-differential operators.Comment: 26 pages. To appear in Ann. Inst. H. Poincare Anal. Non Lineaire.
arXiv admin note: text overlap with arXiv:1405.784
Nonlocal Harnack inequalities
We state and prove a general Harnack inequality for minimizers of nonlocal,
possibly degenerate, integro-differential operators, whose model is the
fractional p-Laplacian.Comment: To appear in J. Funct. Ana
Nonlocal isoperimetric problems
We characterize the volume-constrained minimizers of a nonlocal free energy given by the difference of fractional perimeters. Exploiting the quantitative fractional isoperimetric inequality, we show that balls are the unique minimizers if the volume is sufficiently small, while the existence vs. nonexistence of minimizers for large volumes remains open. We also consider the corresponding isoperimetric problem and prove existence and regularity of minimizers
Type III pleuropulmonary blastoma in a 7-month-old female baby with impending respiratory failure: a case report
INTRODUCTION: Pleuropulmonary blastoma is a very rare, aggressive, embryonal pulmonary neoplasm which mostly affects children under the age of 5. According to the histopathological features, three subtypes of pleuropulmonary blastoma have been recognized: type I (purely cystic), type II (grossly visible cystic and solid elements) and type III (purely solid). Characteristics of type I and type II blastoma allow an earlier diagnosis compared with type III. Here we present a case report of an unusual presentation of type III pleuropulmonary blastoma. CASE PRESENTATION: We describe the case of a 7-month-old female baby of Italian mother and Kurdish father who was diagnosed with type III pleuropulmonary blastoma, which entirely occupied her right hemithorax. CONCLUSIONS: The reported case is an unusual presentation because type III pleuropulmonary blastoma typically occurs in older children. The complete re-expansion of her residual, previously totally compressed, right lung observed immediately after the resection of the lesion suggests an atypical rapid growth of this embryonal tumor in the late phase of gestation or after delivery. This case report suggests that, in addition to other childhood tumors, type III pleuropulmonary blastoma should be included in the differential diagnosis of solid nonhomogeneous thoracic large masses, compressing the mediastinal and chest wall structures in infants. This is an original case report of interest for several specialities such us pediatrics, radiology, surgery and oncology
Scale relativity and fractal space-time: theory and applications
In the first part of this contribution, we review the development of the
theory of scale relativity and its geometric framework constructed in terms of
a fractal and nondifferentiable continuous space-time. This theory leads (i) to
a generalization of possible physically relevant fractal laws, written as
partial differential equation acting in the space of scales, and (ii) to a new
geometric foundation of quantum mechanics and gauge field theories and their
possible generalisations. In the second part, we discuss some examples of
application of the theory to various sciences, in particular in cases when the
theoretical predictions have been validated by new or updated observational and
experimental data. This includes predictions in physics and cosmology (value of
the QCD coupling and of the cosmological constant), to astrophysics and
gravitational structure formation (distances of extrasolar planets to their
stars, of Kuiper belt objects, value of solar and solar-like star cycles), to
sciences of life (log-periodic law for species punctuated evolution, human
development and society evolution), to Earth sciences (log-periodic
deceleration of the rate of California earthquakes and of Sichuan earthquake
replicas, critical law for the arctic sea ice extent) and tentative
applications to system biology.Comment: 63 pages, 14 figures. In : First International Conference on the
Evolution and Development of the Universe,8th - 9th October 2008, Paris,
Franc
Inflammatory macrophages reprogram to immunosuppression by reducing mitochondrial translation
Acute inflammation can either resolve through immunosuppression or persist, leading to chronic inflammation. These transitions are driven by distinct molecular and metabolic reprogramming of immune cells. The anti-diabetic drug Metformin inhibits acute and chronic inflammation through mechanisms still not fully understood. Here, we report that the anti-inflammatory and reactive-oxygen-species-inhibiting effects of Metformin depend on the expression of the plasticity factor ZEB1 in macrophages. Using mice lacking Zeb1 in their myeloid cells and human patient samples, we show that ZEB1 plays a dual role, being essential in both initiating and resolving inflammation by inducing macrophages to transition into an immunosuppressed state. ZEB1 mediates these diverging effects in inflammation and immunosuppression by modulating mitochondrial content through activation of autophagy and inhibition of mitochondrial protein translation. During the transition from inflammation to immunosuppression, Metformin mimics the metabolic reprogramming of myeloid cells induced by ZEB1. Mechanistically, in immunosuppression, ZEB1 inhibits amino acid uptake, leading to downregulation of mTORC1 signalling and a decrease in mitochondrial translation in macrophages. These results identify ZEB1 as a driver of myeloid cell metabolic plasticity, suggesting that targeting its expression and function could serve as a strategy to modulate dysregulated inflammation and immunosuppression.The study was conducted at IDIBAPS’ Centre de
Recerca Biomèdica Cellex building, which was partly funded by the
Cellex Foundation. The different parts of this study were independently
funded by grants to AP from the Leo Foundation (LF-OC-19-000166), the
Catalan Agency for Management of University and Research Grants
(AGAUR) (2017-SGR-1174 and 2021-SGR-01328), and the Spanish State
Research Agency (AEI) of the Ministry of Science and Innovation
(MICINN) (PID2020-116338RB-I00) as part of MICINN’s National Scientific
and Technical Research and Innovation 2021-2023 Plan, which is cofinanced by the European Regional Development Fund (ERDF) of the
European Union Commission. AB is a recipient of a PhD scholarship from
AGAUR (FI Program, 2021 FI_B 00514
Gender-related stress factors and emotional perception in migraine: a structured online questionnaire in migraine patients and controls
Background: While migraine is markedly prevalent in women, gender-related phenotype differences were rarely assessed. For this reason, we investigated, through a multicenter observational cross-sectional study, based on an online questionnaire, gender-related differences in stress factors, emotions, and pain perception in migraine patients and controls and their impact on migraine severity. Methods: The study was designed as an online questionnaire. The link was emailed to healthy subjects (C) and migraine patients (MIG) (age 18-75, education ≥ 13 years) recruited during the first visit in 8 Italian Headache Centers adhering to Italian Society for Headache Study (SISC). The questionnaire included personal/social/work information, the Perceived Stress Scale, the Romance Quality Scale, the Emotion Regulation Questionnaire, the Beck Anxiety Inventory, the Body Perception Questionnaire, the pain perception, and a self-assessment of migraine severity in the last 3 months. Results: 202 MIG and 202 C completed the survey. Independently from gender, migraine was characterized by higher pain sensitivity and more severe partner relationships. The female gender, in MIG, exhibited higher anxiety scores, body awareness, and reduced emotional suppression. Body awareness and emotional suppression were discriminating factors between genders in control and migraine groups without relevant influence on disease features. Perceived perception of migraine severity was similar between genders. Conclusion: Gender-related emotional and stress factors did not contribute to delineate a distinct phenotype in migraine men and women. The possible impact of emotional and stress factors characterizing genders could be considered for a single case-tailored therapeutic approach
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