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Self-reported health and depression among EIRA cohort: a moderated mediation model of sex and perceived social support
Get PDFThe positive relationship between health and good perceived social support has been widely demonstrated in the scientific literature. It is known that having a good social support influences the proper maintenance of health even as a protective factor, besides being a good predictor in the recovery of health during a disease process, influencing differently men and women.AimThis project aims to study the moderating effects of perceived social support in the relationship between depression and self-perceived health according to gender, after a complex multiple-risk intervention was carried out in patients of primary health care with low social support.MethodsA cluster randomized clinical trial was developed in the subgroup of patients included in phase 3 of the EIRA project. CONSORT recommendations were followed to present the results. To determine the mediating effect between social support and self-perceived health, three regression analyses were carried out using the procedure designed by Hayes through the PROCESS macro for SPSS.Results3,062 people (54.9% women) participated in the study. Men reported experiencing more social support and self-perceived health (p < 0.001) than women at the beginning of the study, but women reported higher social support at post-intervention. Moderation analyses showed that, post-intervention, those women (bsimple = −2.9867, p < 0.001) and males (bsimple = −1.4337, p < 0.001) who scored lower in depression reported higher social support.ConclusionIn primary care, it is necessary to encourage intervention strategies that promote social networks as a key element of positive action aimed at maintaining and improving the population’s health, especially in adults and more specifically in women.Clinical trial registrationClinicalTrials.gov, identifier NCT03136211
Receptor de Dopamina 3. Modulación por fármacos y oligomerización
Get PDFLos receptores de dopamina pertenecen al grupo de receptores acoplados a proteínas G aminérgicos, encontrándose principalmente en el cerebro donde participan en multitud de funciones cognitivas y motoras. Al unirse a la dopamina, éstos desencadenan una cascada de señalización intracelular a través de la activación de proteínas G (GS, Gi/O, Gq/11, G12/13) y ß-arrestinas. Se han descrito 5 tipos de receptores dopaminérgicos, clasificados según su secuencia y función en receptores de tipo D1 (D1R y D5R), que señalizan por Gs activando la adenilato ciclasa, y tipo D2 (D2R, D3R y D4R) que señalizan por Gi/O ejerciendo el efecto contrario. Estos últimos, y más específicamente D2R y D3R, constituyen las principales dianas terapéuticas de multitud de trastornos neurológicos, como la enfermedad de Parkinson y esquizofrenia.Comprender los mecanismos funcionales de señalización de estos receptores, así como el desarrollo de fármacos con propiedades optimizadas tiene el potencial de mejorar los tratamientos para estas enfermedades. Esta tesis doctoral se centra en el estudio del D3R humano (hD3R), donde combinando crio-microscopia electrónica, bioquímica, ensayos de señalización y colaboraciones con investigadores computacionales y químicos orgánicos, i) se abordan los mecanismos de señalización de este receptor, mostrando las bases del acoplamiento preferencial de D3R hacia GO, ii) se desarrollan ligandos selectivos que diferencian entre D2R y D3R, explotando un sitio nuevo extracelular en hD3R que se descubre en este trabajo y que se utiliza para el desarrollo de fármacos con mayor selectividad, iii) se descifran los mecanismos por loscuales un ligando unido a la parte extracelular es capaz de activar la señalización mediada por proteínas G pero no por ß-arrestinas en hD3R, iv) se desarrollan nanoanticuerpos que modulan al hD3R permitiendo su uso como herramientas para el estudio del receptor así como v) se pretende el estudio de la oligomerización de estos receptores en ambiente nativo, es decir, mientras se encuentran en la membrana, utilizando crio-tomografía electrónica.<br /
Mecanismos para la implementación y la aplicación efectiva del Reglamento de Mercados Digitales, su aplicación privada y responsabilidad civil de los guardianes de acceso
Get PDFEl presente trabajo tiene por objeto dar cuenta de las cuestiones que en materia de «aplicación efectiva» plantea el Reglamento de Mercados Digitales. Tras realizar una aproximación al estudio de los sistemas de implementación y de aplicación efectiva establecidos en el Reglamento, cabe preguntarse si este deja margen para su aplicación privada, es decir, si cabe esperar que sea posible exigir responsabilidad civil a los guardianes de acceso por los daños que causen sus conductas contrarias al Reglamento, ya sea en su controvertida consideración como una norma de Derecho de defensa de la competencia, ya sea por vías alternativas
Faire Carrière: ascension politique et mobilité sociale dans le monde romain à l'époque républicaine
Get PDFLes Rencontres d’Histoire de la République Romaine (RHiRR) rassemblent depuis 2019 une génération de chercheuses et chercheurs qui ont éprouvé le désir de se retrouver régulièrement afin de réfléchir autour d’un empan chronologique commun. La convivialité, la fluidité de communication, la volonté d’inclusion des plus jeunes sont les vertus attendues des Rencontres. Après un premier colloque organisé à Lorient par Cyrielle Landréa et Caroline Husquin sur la thématique des blessures aristocratiques (publié en 2024)1, deux rencontres ont pris place à Albi (2021, organisation Clément Bur et Thibaud Lanfranchi) et Poitiers (2022, organisation Ghislaine Stouder et Alexandre Vincent), autour de la notion de « faire carrière ». Le présent ouvrage rassemble les actes de ces deux derniers colloques qui n’auraient pu se tenir sans le soutien financier et logistique de l’Université de Toulouse Jean-Jaurès, de l’Institut National Universitaire Champollion et de l’Université de Poitiers, ni l’aide de l’Institut Universitaire de France. Les RHiRR ont depuis connu d’autres éditions, centrées sur la question des violences ordinaires (2023 à Marne-la-Vallée et Nanterre, organisation Robinson Baudry, Audrey Bertrand et Raphaëlle Laignoux) ; et 2024 à Grenoble (organisation Clément Chillet, Marie-Claire Ferriès, Aurélie Larcher). La publication de ce volume retenu dans la collection Libera res publica poursuit ainsi la série de volumes des RhIRR, dont nous ne pouvons qu’espérer qu’elle sera promise à la longévité. Nous tenons ici à remercier chaleureusement Francisco Pina Polo, Cristina Rosillo-López et Antonio Caballos Rufino, pour avoir amicalement ouvert les portes de leur collection à ce volume
A Superpixel-Based Algorithm for Detecting Optical Density Changes in Choroidal Optical Coherence Tomography Images of Diabetic Patients
Get PDFThis study explored the diagnostic potential of image-processing analysis in optical coherence tomography (OCT) images to detect systemic vascular changes in individuals with systemic diseases. Methods: Ocular OCT images from two cohorts diabetic patients and healthy control subjects were analyzed. A novel Superpixel Segmentation (SpS) algorithm was used to process these images and extract optical image density information from ocular vascular tissue. The algorithm was applied to isolate the choroid layer for analysis of its optical properties. The procedure was performed by separate examiners, and both inter- and intra-observer repeatability were assessed. Choroidal area (CA) and choroidal optical image density (COID) metrics were used to assess structural changes in the vascular tissue and predict alterations in the choroidal parameters. Results: A total of 110 diabetic patient eye images and 92 healthy control images were processed. The results showed significant differences in CA and COID between diabetic and healthy eyes, indicating that these parameters could serve as valuable biomarkers for early vascular damage. Conclusions: The use of the SpS algorithm on OCT B-scan images allows for the identification of new parameters linked to ocular vascular damage. These findings suggest that digital image-processing techniques can reveal differences in vascular tissue, offering potential new indicators of pathology
Serum-Based Detection of Pancreatic and Ovarian Cancer via a Nanoparticle-Enhanced Fluorescence Array and Machine Learning
No full textEarly detection of oncological diseases such as pancreatic ductal adenocarcinoma (PDAC) and ovarian cancer (OV) is pivotal for successful treatment but remains a significant challenge due to the lack of sensitive and specific diagnostic tests. Fluorescence spectroscopy, enhanced by the interaction of serum proteins with nanoparticles (NPs) based on linear–dendritic block copolymers, has emerged as a promising technique for the noninvasive detection of these malignancies. This study introduces a novel array-based assay methodology to evaluate the diagnostic capabilities of various NPs within serum samples using fluorescence. Methods: We synthesized three types of NPs (1-SH, 2-OH, 3-NH3+) and analyzed their fluorescence spectra in serum samples from patients with PDAC, OV, and control subjects. The samples were excited at 330 and 350 nm wavelengths to obtain their fluorescence emission spectra. An array of machine learning algorithms was applied, including boosting and tree-based methods, to assess the ability of the spectral data to discriminate between pathological and nonpathological states. The algorithms’ performance was measured by the area under the receiver operating characteristic curves (AUC). Results: The fluorescence spectra revealed distinct patterns for PDAC and OV pathologies. 3-NH3+ NPs exhibited the highest differential capacity with AUCs exceeding 80% for PDAC across all algorithms, except one. 2-OH NPs showed a strong discriminatory ability for OV with AUCs over 70%, utilizing all but one of the algorithms. 1-SH NPs, however, did not significantly increase differentiability. Boosting algorithms generally outperformed other methods, indicating their suitability for this diagnostic approach. Conclusions: The proposed assay array methodology enables the systematic evaluation of NPs’ diagnostic potential using fluorescence spectroscopy. The differential interactions between NPs and serum proteins specific to PDAC and OV highlight the method’s capability to discern pathological states. These findings suggest a path forward for developing NP-assisted fluorescence spectroscopy as a viable tool for cancer diagnostics, potentially leading to earlier detection and improved patient outcomes
Embedding Externalisation: How Bordering Practices Transform Places
No full textOver the past twenty years, research into border externalisation has developed a rich spatial vocabulary to understand these bordering practices as well as critical analyses that challenge the often North-centric views towards externalisation. In this Special Issue, we emphasise that a place-based gaze can lend new mileage to border externalisation research. We emphasise that the place has been under-theorised and under examined in its relation to border externalisation. Existing work often has an implicit framing that understands externalisation as part of a migrant vs. border dialectic, or as part of geopolitical relations between states. By focusing on place, we argue that border externalisation: generates new contexts by connecting previously disparate sites into a border continuum; is place dependent, as its different forms are contingent on situated dynamics; and is place transformative, the border changes the social dynamics of the places where it is implemented
Modifying vacancy defects during systematic disordering of the Cr2AlC nano-lamellar system
Get PDFThe layered structure of MAX phases is associated with a number of functional properties and is the subject of extensive research. While the unit-cell layers of these structures have been well studied, much less is known about the distribution and manipulation of point defects within them. Here, we selected the prototype Cr2AlC system and, using variable energy positron beams, observed Doppler broadening and positron annihilation lifetimes to track the evolution of defects caused by the penetration of energetic transition metal ions (Co+ and Mn+) and noble gas ions (Ar+ and Ne+). In all cases an overall reduction of the open-volume defect concentration is observed post-irradiation. Atomic displacements induced by the penetrating ions drastically modify the defect distribution: the concentration of agglomerates of 9–15 vacancies (corresponding to positron lifetimes of 335–450 ps) in the precursor [Cr2C/Al]n layers is suppressed, whereas Al mono- and Al-Cr di-vacancy (lifetimes 217–231 ps) concentrations are enhanced. This breakdown of large defects into point defects scales with atomic displacements and is largely independent of the penetrating ion species, providing insights into the manipulation of point defects in nano-layered systems
Predictors of landscape preferences in large hotel complex tourism
No full textThis study analyses the landscape preferences of large hotel complex tourism in Cuba using an approach based on the classic Kaplan (1989) matrix, expanding it with two complementary variables ("Sense of Being Away" and "Aesthetic Appeal"). The objectives of the study include, firstly, verifying whether the variables of the proposed model are valid determinants of landscape preferences. Secondly, studying the relationships between these variables and the Construction Intensity (associated with the different types of hotel complexes). And finally, to determine the ideal set of factors to predict landscape preferences. To this end, undergraduate and postgraduate students in Spain and Brazil were surveyed regarding their landscape preferences using photographs of landscapes with and without tourist constructions. The results indicate that Aesthetic Appeal is the variable that correlates best with General Preference, followed by Mystery and Harmony, while Diversity shows the weakest correlation. Another relevant finding is that the behaviour of the six variables of the "extended Kaplan" model is affected by Construction Intensity, with the models that include this variable having the greatest explanatory power. Finally, the model with the highest predictive ability for General Preference combines Harmony, Aesthetic Appeal and Mystery. The results support the strength of the proposed "extended Kaplan" model and the relative importance of considering Construction Intensity in landscape preference analyses. It is perceived that there is a need for enhanced landscape integration of tourism developments to unite customer satisfaction with landscape conservation
Positive Hankel Matrices, Eigenvalues and Total Positivity
No full textFor positive Hankel matrices, an interval containing all eigenvalues is obtained. With a stronger condition, we also construct two sharper intervals for the eigenvalue localization. The total positivity of positive Hankel matrices is analyzed. The relationship between Hankel TP matrices and some Toeplitz SR matrices is analyzed