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1.
Assist Inferm Ric ; 43(2): 83-90, 2024.
Artigo em Italiano | MEDLINE | ID: mdl-38873717

RESUMO

. The overlap Stevens-Johnson syndrome due to meropenem administration. Clinical case and nursing care. A case of overlap Stevens-Johnson syndrome caused by meropenem administration is described. It is a rare cutaneous reaction due to delayed hypersensitivity to drugs characterised by the destruction and separation of the skin epithelium and mucous membranes, affecting between 10% and 29% of the body surface area. The clinical description of the case and a detailed description of nursing management and interventions based on the available literature are reported.


Assuntos
Antibacterianos , Meropeném , Síndrome de Stevens-Johnson , Síndrome de Stevens-Johnson/enfermagem , Síndrome de Stevens-Johnson/etiologia , Humanos , Meropeném/administração & dosagem , Meropeném/efeitos adversos , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Feminino , Masculino , Tienamicinas/administração & dosagem , Tienamicinas/efeitos adversos
2.
Mater Struct ; 57(4): 56, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601013

RESUMO

The steel-concrete interface (SCI) is known to play a major role in corrosion of steel in concrete, but a fundamental understanding is still lacking. One reason is that concrete's opacity complicates the study of internal processes. Here, we report on the application of bimodal X-ray and neutron microtomography as in-situ imaging techniques to elucidate the mechanism of steel corrosion in concrete. The study demonstrates that the segmentation of the specimen components of relevance-steel, cementitious matrix, aggregates, voids, corrosion products-obtained through bimodal X-ray and neutron imaging is more reliable than that based on the results of each of the two techniques separately. Further, we suggest the combination of tomographic in-situ imaging with ex-situ SEM analysis of targeted sections, selected based on the segmented tomograms. These in-situ and ex-situ characterization techniques were applied to study localized corrosion in a very early stage under laboratory chloride-exposure conditions, using reinforced concrete cores retrieved from a concrete bridge. Several interesting observations were made. First, the acquired images revealed the formation of several corrosion sites close to each other. Second, the morphology of the corrosion pits was relatively shallow. Finally, only about half of the total 31 corrosion initiation spots were in close proximity to interfacial macroscopic air voids, and > 90% of the more than 160 interfacial macroscopic air voids were free from corrosion. The findings have implications for the mechanistic understanding of corrosion of steel in concrete and suggest that multimodal in-situ imaging is a valuable technique for further related studies. Supplementary Information: The online version contains supplementary material available at 10.1617/s11527-024-02337-7.

3.
Biol Sport ; 41(1): 207-215, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38188116

RESUMO

The aims of the current study were to determine the most demanding passages of match play (MDP) and the distribution of match activities relative to maximum intensities during official matches in top-class women soccer players. Twenty-eight women players competing in European championship and international UEFA competitions were monitored during 38 official matches (277 individual samples). Maximum relative (m · min-1) total distance (TD), high-speed running (HSRD), very high-speed running (VHSRD), sprint, acceleration and deceleration distances were calculated across different durations (1-5, 10, 15, 90 min) using a rolling average analysis. Maximum intensities (1-minpeak) were used as the reference value to determine the distribution of relative intensity across the whole-match demands (90-minavg). Time and distance higher than 90-minavg (> 90-minavg) were also calculated. MDP showed moderate to very large [effect size (ES): 0.63/5.20] differences between 1-minpeak vs all durations for each parameter. The relative (m · min-1) 1-minpeak was greater than 90-minavg of about +63% for TD, +358% for HSRD, +969% for VHSRD, +2785% for sprint, +1216% for acceleration, and +768% for deceleration. The total distance covered > 90-minavg was ~66.6% of the total distance covered during the 90-minavg for TD, ~84.8% for HSRD, ~97.4% for VHSRD, ~100% for sprint, ~99.1% for acceleration and ~98.2% for deceleration. The relative distance > 90-minavg was higher (P < 0.05) than the 90-minavg for each metric (ES: 2.22 to 7.58; very large). The present results may help coaches and sport scientists to replicate the peak demands during training routine in top-class women soccer players.

4.
iScience ; 26(7): 107098, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37416469

RESUMO

Parliament dynamics might seem erratic at times. Predicting future voting patterns could support policy design based on the simulation of voting scenarios. The availability of open data on legislative activities and machine learning tools might enable such prediction. In our paper, we provide evidence for this statement by developing an algorithm able to predict party switching in the Italian Parliament with over 70% accuracy up to two months in advance. The analysis was based on voting data from the XVII (2013-2018) and XVIII (2018-2022) Italian legislature. We found party switchers exhibited higher participation in secret ballots and showed a progressive decrease in coherence with their party's majority votes up to two months before the actual switch. These results show how machine learning combined with political open data can support predicting and understanding political dynamics.

5.
J Med Chem ; 65(7): 5565-5574, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35357834

RESUMO

Structure-based drug discovery (SBDD) largely relies on structural information from X-ray crystallography because traditional NMR structure calculation methods are too time consuming to be aligned with typical drug discovery timelines. The recently developed NMR molecular replacement (NMR2) method dramatically reduces the time needed to generate ligand-protein complex structures using published structures (apo or holo) of the target protein and treating all observed NOEs as ambiguous restraints, bypassing the laborious process of obtaining sequence-specific resonance assignments for the protein target. We apply this method to two therapeutic targets, the bromodomain of TRIM24 and the second bromodomain of BRD4. We show that the NMR2 methodology can guide SBDD by rationalizing the observed SAR. We also demonstrate that new types of restraints and selective methyl labeling have the potential to dramatically reduce "time to structure" and extend the method to targets beyond the reach of traditional NMR structure elucidation.


Assuntos
Proteínas Nucleares , Fatores de Transcrição , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Proteínas Nucleares/metabolismo , Ligação Proteica , Domínios Proteicos , Fatores de Transcrição/metabolismo
6.
Polymers (Basel) ; 14(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35267748

RESUMO

In this study, the applicability of two bacteria-based healing agents (e.g., poly-lactic acid and polyhydroxyalkanoate) in blast furnace slag cement (BFSC) mortar has been assessed. An experimental campaign on the functional properties, self-healing capacity, freezing-thawing and carbonation resistance has been conducted in comparison with plain mortar (Ctrl). Due to the relatively low alkalinity of the mixture, the addition of poly-lactic acid healing agents (PLA) caused coarsening of the micro-structure, decrease of strength and did not improve the self-healing capacity of the material. Among other consequences, the mass loss due to the freezing-thawing of PLA specimens was about 5% higher than that of the Ctrl specimens. On the contrary, no detrimental effect of the mortar functional properties was measured when polyhydroxyalkanoate healing agents (AKD) were added. The self-healing capacity of AKD specimens was higher than that of the Ctrl specimens, reaching a maximum healed crack width of 559 µm after 168 days of self-healing, while it was 439 µm for the Ctrl specimens and 385 µm for PLA specimens. The air void content of the AKD mixture was 0.9% higher than that of the Ctrl, increasing its resistance against freezing-thawing cycles. This study aims to confirm the potential applicability of AKD particles as self-healing agents in low-alkaline cementitious mixtures.

7.
J Microsc ; 286(2): 58-62, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34921557

RESUMO

Since self-healing of cementitious materials can theoretically improve the service-life of concrete structures, it has gathered significant attention from both researchers and industry during the last two decades. Many researchers have proposed different methods to assess and quantify the self-healing capacity (i.e. the ability of cementitious materials to heal cracks) that is generated in concrete autogenously as well as autonomously. Even though many methodologies can be found in the literature, a way to accurately quantify the healing products produced by any self-healing mechanism has not been yet achieved. In this study, a methodology is proposed to observe and to quantify in-time formation of healing products based on active thin sections. Thin sections of Portland cement paste have been prepared with no epoxy impregnation to facilitate reactions between the cement matrix and the surrounding environment. Artificial cracks (260 µm wide) were induced at 28 days of age and the crystal growth was continuously monitored up to 28 days of self-healing. Through image analysis of the micrographs, it was calculated that the autogenous self-healing capacity of paste (triggered by portlandite carbonation in uncontrolled indoor conditions) was around 55% after 28 days of self-healing. Healing products were further characterised through Environmental Scanning Electron Microscope analysis. Based on the results obtained in this study, the proposed methodology seems to be promising to compare the self-healing mechanisms triggered by different healing agents.

8.
Soft Matter ; 17(24): 6006-6019, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34059862

RESUMO

This study presents an analysis of the dynamics of single and multiple chains of spherical super-paramagnetic beads suspended in a Newtonian fluid under the combined effect of an external rotating magnetic field and a shear flow. Viscosity results depend on two main non-dimensional numbers: the ratio between the shear rate and the magnetic rotation frequency and the ratio between the hydrodynamic and magnetostatic interactions (the Mason number). When the shear rate is smaller than the magnetic field frequency, the chain rotation accelerates the surrounding fluid, reducing the value of the measured suspension viscosity even below that of the solvent. In this regime, shear-thickening is observed. For values of the shear rates comparable to the rotation magnetic frequency, the viscosity reaches a maximum and non-linear coupling effects come up. If the shear rate is increased to values above the rotation frequency, the viscosity decreases and a mild shear-thinning is observed. In terms of the Mason number, the suspension viscosity reduces in line with the literature results reported for fixed magnetic fields, whereas the shear-rate/magnetic-frequency ratio parameters induce a shift of the viscosity curve towards larger values. Results at larger concentrations and multiple chains amplify the observed effects.

9.
Faraday Discuss ; 228(0): 451-469, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-33605959

RESUMO

We present a combined theoretical and experimental study of X-ray optical wave mixing. This class of nonlinear phenomena combines the strengths of spectroscopic techniques from the optical domain, with the high-resolution capabilities of X-rays. In particular, the spectroscopic sensitivity of these phenomena can be exploited to selectively probe valence dynamics. Specifically, we focus on the effect of X-ray parametric down-conversion. We present a theoretical description of the process, from which we deduce the observable nonlinear response of valence charges. Subsequently, we simulate scattering patterns for realistic conditions and identify characteristic signatures of the nonlinear conversion. For the observation of this signature, we present a dedicated experimental setup and results of a detailed investigation. However, we do not find evidence of the nonlinear effect. This finding stands in strong contradiction to previous claims of proof-of-principle demonstrations. Nevertheless, we are optimistic to employ related X-ray optical wave mixing processes on the basis of the methods presented here for probing valence dynamics in the future.

10.
J Phys Chem Lett ; 11(6): 1981-1988, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32073862

RESUMO

Femtosecond X-ray absorption spectroscopy (XAS) is a powerful method to investigate the dynamical behavior of a system after photoabsorption in real time. So far, the application of this technique has remained limited to large-scale facilities, such as femtosliced synchrotrons and free-electron lasers (FEL). In this work, we demonstrate femtosecond time-resolved soft-X-ray absorption spectroscopy of liquid samples by combining a sub-micrometer-thin flat liquid jet with a high-harmonic tabletop source covering the entire water-window range (284-538 eV). Our work represents the first extension of tabletop XAS to the oxygen edge of a chemical sample in the liquid phase. In the time domain, our measurements resolve the gradual appearance of absorption features below the carbon K-edge of ethanol and methanol during strong-field ionization and trace the valence-shell ionization dynamics of the liquid alcohols with a temporal resolution of ∼30 fs. This technique opens unique opportunities to study molecular dynamics of chemical systems in the liquid phase with elemental, orbital, and site sensitivity.

11.
Materials (Basel) ; 14(1)2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33396368

RESUMO

Recent studies have shown promising potential for using Glass Pozzolan (GP) as an alternative supplementary cementitious material (SCM) due to the scarcity of fly ash and slag in the United States. However, comprehensive studies on the freeze-thaw (FT) resistance and air void system of mixtures containing GP are lacking. Therefore, this study aimed to evaluate GP's effect on FT resistance and characterize mixtures with different GP contents, both macro- and microscopically. In this study, six concrete mixes were considered: Three mixes with 20%, 30% and 40% GP as cement replacements and two other comparable mixes with 30% fly ash and 40% slag, as well as a mix with 100% Ordinary Portland cement (OPC) as a reference. Concrete samples were prepared, cured and tested according to the ASTM standards for accelerated FT resistance for 1000 cycles and corresponding dynamic modulus of elasticity (Ed). All the samples showed minimal deterioration and scaling and high F/T resistance with a durability factor of over 90%. The relationships among FT resistance parameters, air-pressured method measurements of fresh concretes and air void analysis parameters of hardened concretes were examined in this study. X-ray micro-tomography (micro-CT scan) was used to evaluate micro-cracks development after 1000 freeze-thaw cycles and to determine spatial parameters of air voids in the concretes. Pore structure properties obtained from mercury intrusion porosimetry (MIP) and N2 adsorption method showed refined pore structure for higher cement replacement with GP, indicating more gel formation (C-S-H) which was verified by thermogravimetric analysis (TGA).

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