246 research outputs found
Peptide profiling by capillary separation techniques coupled to mass spectrometry
This thesis describes very sensitive methods for peptide detection, obtained by the coupling of high efficiency capillary chromatographic techniques to mass spectrometry. The application of novel data preprocessing methods to the analysis of such complex MS data generated is also described. The data analysis step was completed by the use of multivariate statistical analysis tools, such as principal component analysis (PCA). The developed platform could be applied to the study of complex peptide mixtures and of proteomic samples.TNO Quality of LifeUBL - phd migration 201
Thermal management of a Formula E electric motor: Analysis and optimization
The thermal analysis of a high performance brushless synchronous electric motor with permanent magnets and water jacket cooling is presented. The analysis is carried out following a lumped parameter thermal network approach which allows to identify the most important thermal paths in the motor and the main parameters influencing them. Thanks to its simplicity, the solution of such a thermal network model is very fast, allowing a large number of what-if scenarios to be computed over a short amount of time. For this reason, the model is coupled with external tools for performing systematic sensitivity analyses and optimizations. Goal of the investigation is the reduction of the windings temperature being this temperature inversely proportional to the efficiency and the power delivered by the motor. The sensitivity analysis, performed over a series of material, geometric, and operational factors, leads to the identification of the most relevant parameters influencing the thermal behaviour of the motor. A series of optimizations, focusing on these parameters and including suitable constraints granting the well-posedness of the problem and the feasibility of the solution, bring to the definition of an optimum layout of the water jacket and of the stator geometries. The optimized geometry allows a significant reduction of the windings temperature to be achieved
Migraciones, comunidades etnificadas y consumo de alcohol
Este trabajo analiza, desde una perspectiva socioantropológica, el papel que adquieren algunos patrones de consumo de alcohol asociados a la masculinidad entre la comunidad ecuatoriana en Génova, Italia. La práctica del consumo de alcohol, en contextos homosociales de migración y asociada a actividades deportivas, está (re)significada bajo parámetros culturales instituidos como “ritualidad alcohólica de la masculinidad”. Alejándonos de un enfoque de patologización del consumo, y adentrándonos en el estudio de las “culturas del alcohol”, migración y consumo, exploramos sobre los significados del tomar ecuatorianizado en tres escenarios de identidad cultural en tanto que estrategias de territorialización
Highly efficient human serum filtration with water-soluble nanoporous nanoparticles
Antonella Pujia1, Francesco De Angelis1,2, Domenica Scumaci3, Marco Gaspari3, Carlo Liberale1,2, Patrizio Candeloro1, Giovanni Cuda3, Enzo Di Fabrizio1,21BIONEM Laboratory, Department of Experimental and Clinical Medicine, University of Catanzaro “Magna Graecia”, Germaneto (CZ), Italy; 2IIT, Italian Institute of Technology, Genova, Italy; 3Proteomics and Mass Spectrometry Laboratory, Department of Experimental and Clinical Medicine, University of Catanzaro “Magna Graecia”, Germaneto (CZ), ItalyBackground: Human serum has the potential to become the most informative source of novel biomarkers, but its study is very difficult due to the incredible complexity of its molecular composition. We describe a novel tool based on biodegradable nanoporous nanoparticles (NPNPs) that allows the harvesting of low-molecular-weight fractions of crude human serum or other biofluids. NPNPs with a diameter of 200 nm and pore size of a few nm were obtained by ultrasonication of nanoporous silicon. When incubated with a solution, the NPNPs harvest only the molecules small enough to be absorbed into the nanopores. Then they can be recovered by centrifugation and dissolved in water, making the harvested molecules available for further analyses.Results: Fluorescence microscopy, gel electrophoresis, and mass spectrometry were used to show the enrichment of low-molecular-weight fraction of serum under physiological conditions, with a cut-off of 13 kDa and an enrichment factor >50.Conclusion: From these findings, we conclude that ability to tune pore size, combined with the availability of hundreds of biomolecule cross-linkers, opens up new perspectives on complex biofluid analysis, discovery of biomarkers, and in situ drug delivery.Keywords: nanoporous silicon, nanoparticle, biomarker discovery, human serum proteomics, harvestin
Supermassive black hole winds in X-rays: SUBWAYS: II. HST UV spectroscopy of winds at intermediate redshifts
We present a UV spectroscopic study of ionized outflows in 21 active galactic nuclei (AGN), observed with the Hubble Space Telescope (HST). The targets of the Supermassive Black Hole Winds in X-rays (SUBWAYS) sample were selected with the aim to probe the parameter space of the underexplored AGN between the local Seyfert galaxies and the luminous quasars at high redshifts. Our targets, spanning redshifts of 0.1–0.4 and bolometric luminosities (Lbol) of 1045–1046 erg s-1, have been observed with a large multi-wavelength campaign using XMM-Newton, NuSTAR, and HST. Here, we model the UV spectra and look for different types of AGN outflows that may produce either narrow or broad UV absorption features. We examine the relations between the observed UV outflows and other properties of the AGN. We find that 60% of our targets show a presence of outflowing H¿I absorption, while 40% exhibit ionized outflows seen as absorption by either C¿IV, N¿V, or O¿VI. This is comparable to the occurrence of ionized outflows seen in the local Seyfert galaxies. All UV absorption lines in the sample are relatively narrow, with outflow velocities reaching up to -3300 km s-1. We did not detect any UV counterparts to the X-ray ultra-fast outflows (UFOs), most likely due to their being too highly ionized to produce significant UV absorption. However, all SUBWAYS targets with an X-ray UFO that have HST data demonstrate the presence of UV outflows at lower velocities. We find significant correlations between the column density (N) of the UV ions and Lbol of the AGN, with NH I decreasing with Lbol, while NO VI is increasing with Lbol. This is likely to be a photoionization effect, where toward higher AGN luminosities, the wind becomes more ionized, resulting in less absorption by neutral or low-ionization ions and more absorption by high-ionization ions. In addition, we find that N of the UV ions decreases as their outflow velocity increases. This may be explained by a mechanical power that is evacuating the UV-absorbing medium. Our observed relations are consistent with multiphase AGN feeding and feedback simulations indicating that a combination of both radiative and mechanical processes are in play.Peer ReviewedPostprint (published version
Compact object mergers: exploring uncertainties from stellar and binary evolution with SEVN
Population-synthesis codes are an unique tool to explore the parameter space
of massive binary star evolution and binary compact object (BCO) formation.
Most population-synthesis codes are based on the same stellar evolution model,
limiting our ability to explore the main uncertainties. Our code SEVN overcomes
this issue by interpolating the main stellar properties from a set of
pre-computed evolutionary tracks. With SEVN, we evolved
binaries in the metallicity range , exploring a number
of models for electron-capture, core-collapse and pair-instability supernovae,
different assumptions for common envelope, stability of mass transfer,
quasi-homogeneous evolution and stellar tides. We find that stellar evolution
has a dramatic impact on the formation of single and binary compact objects.
Just by slightly changing the overshooting parameter () and the pair-instability model, the maximum mass of a black hole
can vary from to . Furthermore,
the formation channels of BCOs and the merger efficiency we obtain with SEVN
show significant differences with respect to the results of other
population-synthesis codes, even when the same binary-evolution parameters are
used. For example, the main traditional formation channel of BCOs is strongly
suppressed in our models: at high metallicity () only % of
the merging binary black holes and binary neutron stars form via this channel,
while other authors found fractions %. The local BCO merger rate density
of our fiducial models is consistent with the most recent estimates by the
LIGO--Virgo--KAGRA collaboration.Comment: Submitted to MNRAS, comments welcome! The SEVN code is available at
https://gitlab.com/sevncodes/sevn.git. All the data underlying this article
are available in Zenodo at the link https://doi.org/10.5281/zenodo.7260771.
All the Jupyter notebooks used to produce the plots in the paper are
available in the gitlab repository https://gitlab.com/iogiul/iorio22_plot.gi
Human adipose-derived mesenchymal stem cell-conditioned medium ameliorates polyneuropathy and foot ulceration in diabetic BKS db/db mice
Background: Diabetic polyneuropathy (DPN) is the most common and early developing complication of diabetes mellitus, and the key contributor for foot ulcers development, with no specific therapies available. Different studies have shown that mesenchymal stem cell (MSC) administration is able to ameliorate DPN; however, limited cell survival and safety reasons hinder its transfer from bench to bedside. MSCs secrete a broad range of antioxidant, neuroprotective, angiogenic, and immunomodulatory factors (known as conditioned medium), which are all decreased in the peripheral nerves of diabetic patients. Furthermore, the abundance of these factors can be boosted in vitro by incubating MSCs with a preconditioning stimulus, enhancing their therapeutic efficacy. We hypothesize that systemic administration of conditioned medium derived from preconditioned MSCs could reverse DPN and prevent foot ulcer formation in a mouse model of type II diabetes mellitus. Methods: Diabetic BKS db/db mice were treated with systemic administration of conditioned medium derived from preconditioned human MSCs; conditioned medium derived from non-preconditioned MSCs or vehicle after behavioral signs of DPN was already present. Conditioned medium or vehicle administration was repeated every 2 weeks for a total of four administrations, and several functional and structural parameters characteristic of DPN were evaluated. Finally, a wound was made in the dorsal surface of both feet, and the kinetics of wound closure, re-epithelialization, angiogenesis, and cell proliferation were evaluated. Results: Our molecular, electrophysiological, and histological analysis demonstrated that the administration of conditioned medium derived from non-preconditioned MSCs or from preconditioned MSCs to diabetic BKS db/db mice strongly reverts the established DPN, improving thermal and mechanical sensitivity, restoring intraepidermal nerve fiber density, reducing neuron and Schwann cell apoptosis, improving angiogenesis, and reducing chronic inflammation of peripheral nerves. Furthermore, DPN reversion induced by conditioned medium administration enhances the wound healing process by accelerating wound closure, improving the re-epithelialization of the injured skin and increasing blood vessels in the wound bed in a skin injury model that mimics a foot ulcer. Conclusions: Studies conducted indicate that MSC-conditioned medium administration could be a novel cell-free therapeutic approach to reverse the initial stages of DPN, avoiding the risk of lower limb amputation triggered by foot ulcer formation and accelerating the wound healing process in case it occurs.Fil: De Gregorio, Cristian. Universidad del Desarrollo; ChileFil: Contador, David. Universidad del Desarrollo; ChileFil: Díaz, Diego. Universidad del Desarrollo; ChileFil: Cárcamo, Constanza. Universidad del Desarrollo; ChileFil: Santapau, Daniela. Universidad del Desarrollo; ChileFil: Lobos Gonzalez, Lorena. Universidad del Desarrollo; ChileFil: Acosta, Cristian Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Campero, Mario. Universidad de Chile; ChileFil: Carpio, Daniel. Universidad Austral de Chile; ChileFil: Gabriele, Caterina. University Of Catanzaro; ItaliaFil: Gaspari, Marco. University Of Catanzaro; ItaliaFil: Aliaga Tobar, Victor. Universidad de Chile; ChileFil: Maracaja Coutinho, Vinicius. Universidad de Chile; ChileFil: Ezquer, Marcelo. Universidad del Desarrollo; ChileFil: Ezquer, Fernando. Universidad del Desarrollo; Chil
ETS-related gene (ERG) undermines genome stability in mouse prostate progenitors via Gsk3β dependent Nkx3.1 degradation.
21q22.2-3 deletion is the most common copy number alteration in prostate cancer (PCa). The genomic rearrangement results in the androgen-dependent de novo expression of ETS-related gene (ERG) in prostate cancer cells, a condition promoting tumor progression to advanced stages of the disease. Interestingly, ERG expression characterizes 5-30% of tumor precursor lesions - High Grade Prostatic Intraepithelial Neoplasia (HGPIN) - where its role remains unclear. Here, by combining organoids technology with Click-chemistry coupled Mass Spectrometry, we demonstrate a prominent role of ERG in remodeling the protein secretome of prostate progenitors. Functionally, by lowering autocrine Wnt-4 signaling, ERG represses canonical Wnt pathway in prostate progenitors, and, in turn, promotes the accumulation of DNA double strand breaks via Gsk3β-dependent degradation of the tumor suppressor Nkx3.1. On the other hand, by shaping extracellular paracrine signals, ERG strengthens the pro-oxidative transcriptional signature of inflammatory macrophages, which we demonstrate to infiltrate pre-malignant ERG positive prostate lesions. These findings highlight previously unrecognized functions of ERG in undermining adult prostate progenitor niche through cell autonomous and non-autonomous mechanisms. Overall, by supporting the survival and proliferation of prostate progenitors in the absence of growth stimuli and promoting the accumulation of DNA damage through destabilization of Nkx3.1, ERG could orchestrate the prelude to neoplastic transformation
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