Search results for "Solution"

MAST-RT0 SOLUTION OF 3D NAVIER STOKES EQUATIONS ON UNSTRUCTURED MESHS. PRELIMINARY RESULTS IN THE LAMINAR CASE

2021

MAST-RT0 solution of 3D Navier Stokes equations in very irregular domains. Preliminary results in the laminar case

2021

A new numerical methodology to solve the 3D Navier-Stokes equations for incompressible fluids within complex boundaries and unstructured body-fitted tetrahedral mesh is presented and validated with three literature and one real-case tests. We apply a fractional time step procedure where a predictor and a corrector problem are sequentially solved. The predictor step is solved applying the MAST (Marching in Space and Time) procedure, which explicitly handles the non-linear terms in the momentum equations, allowing numerical stability for Courant number greater than one. Correction steps are solved by a Mixed Hybrid Finite Elements discretization that assumes positive distances among tetrahedr…

Polyoxypregnanes as safe, potent, and specific ABCB1-inhibitory pro-drugs to overcome multidrug resistance in cancer chemotherapy in vitro and in vivo

2021

Multidrug resistance (MDR) mediated by ATP binding cassette subfamily B member 1 (ABCB1) is significantly hindering effective cancer chemotherapy. However, currently, no ABCB1-inhibitory drugs have been approved to treat MDR cancer clinically, mainly due to the inhibitor specificity, toxicity, and drug interactions. Here, we reported that three polyoxypregnanes (POPs) as the most abundant constituents of Marsdenia tenacissima (M. tenacissima) were novel ABCB1-modulatory pro-drugs, which underwent intestinal microbiota-mediated biotransformation in vivo to generate active metabolites. The metabolites at non-toxic concentrations restored chemosensitivity in ABCB1-overexpressing cancer cells v…

The BRICS Centres of Dispute Resolution: causes, state of the art, and prospects

2023

The idea of an enhanced cooperation and exchange of knowledge and best practices among its member states in the fields of trade, commerce, and investments -among others- is at the heart of BRICS. In fact, intra-BRICS trade has nearly tripled over the last decade, supported by an increase in intra-regional trade for all member countries. Thanks to their influential and remarkable progress in promoting local currency (for de-dollarisation purposes), regional FDI, and regional trade, the BRICS economies have emerged and have taken a new space in the twenty-first century. This reinforced one of the core objectives pursued by BRICS which is that of enhancing the five developing economies’ role i…

Acceso a la Justicia de los Consumidores a través del ADR y del ODR

2018

El avance de las tecnologías de información y la comunicación nos ha llevado a cambiar nuestra forma de relacionarnos tanto entre nosotros, como con las administraciones. Además, la adquisición de bienes de consumo a través del medio online es cada día más importante para en la economía global y doméstica. Todo ello, llevó a la Unión Europea a la creación del llamado Mercado Único Digital, donde se estableció como uno de los objetivos prioritarios mejorar la tutela efectiva de los ciudadanos comunitarios que realizan compras a través de internet. El presente trabajo tiene por objeto realizar un análisis sobre las facilidades y dificultades que encuentran los consumidores a la hora de accede…

Ricerche in tema di società questuarie

2019

Intorno al regime delle società di tipo questuario – riconducibili agli schemi teorici della societas universorum quae ex quaestu veniunt – e delle società unius alicuius negotiationis e unius rei, si profusero gli sforzi interpretativi dei giuristi romani, fin dalla fine dell’età repubblicana. La monografia scientifica ripercorre le tracce della individuazione della nozione stessa di quaestus (guadagno), con particolare riferimento alla inclusione al suo interno delle donazioni cd. remuneratorie; ancora, ricostruisce il dibattito giurisprudenziale sorto intorno alla questione se i soci – nella determinazione delle quote – dovessero rispettare una proporzione rispetto ai conferimenti, con u…

Isocratic and gradient elution in micellar liquid chromatography with Brij-35

2015

Polyoxyethylene(23)lauryl ether (known as Brij-35) is a nonionic surfactant, which has been considered as an alternative to the extensively used in micellar liquid chromatography anionic surfactant sodium lauryl (dodecyl) sulfate, for the analysis of drugs and other types of compounds. Brij-35 is the most suitable nonionic surfactant for micellar liquid chromatography, owing to its commercial availability, low cost, low toxicity, high cloud temperature, and low background absorbance. However, it has had minor use. In this work, we gather and discuss some results obtained in our laboratory with several β-blockers, sulfonamides, and flavonoids, concerning the use of Brij-35 as mobile phase mo…

Improving Dissolution Behavior and Oral Absorption of Drugs with pH-Dependent Solubility Using pH Modifiers: A Physiologically Realistic Mass Transpo…

2021

Orally dosed drugs must dissolve in the gastrointestinal (GI) tract before being absorbed through the epithelial cell membrane. In vivo drug dissolution depends on the GI tract's physiological conditions such as pH, residence time, luminal buffers, intestinal motility, and transit and drug properties under fed and fasting conditions (Paixao, P. et al. Mol. Pharm. 2018 and Bermejo, et al. M. Mol. Pharm. 2018). The dissolution of an ionizable drug may benefit from manipulating in vivo variables such as the environmental pH using pH-modifying agents incorporated into the dosage form. A successful example is the use of such agents for dissolution enhancement of BCS class IIb (high-permeability,…

Viscosity-mediated negative food effect on oral absorption of poorly-permeable drugs with an absorption window in the proximal intestine: In vitro ex…

2014

Concomitant food intake can diminish oral absorption of drugs with limited permeability and an absorption window in the proximal intestine, due to viscosity-mediated decrease in dosage form disintegration time and drug dissolution rate. Three poorly-permeable drugs (atenolol, metformin hydrochloride, and furosemide) exhibiting negative food effect, and one highly-soluble and highly-permeable (metoprolol tartrate), serving as a negative control, were selected for the study. In vitro and in silico tools were used to evaluate the influence of media viscosity on drug bioperformance under fasted and fed conditions. The obtained results demonstrated that increased medium viscosity in the presence…

Development and Characterization of an Amorphous Solid Dispersion of Furosemide in the Form of a Sublingual Bioadhesive Film to Enhance Bioavailabili…

2017

Administered by an oral route, Furosemide (FUR), a diuretic used in several edematous states and hypertension, presents bioavailability problems, reported as a consequence of an erratic gastrointestinal absorption due to various existing polymorphic forms and low and pH-dependent solubility. A mucoadhesive sublingual fast-dissolving FUR based film has been developed and evaluated in order to optimize the bioavailability of FUR by increasing solubility and guaranteeing a good dissolution reproducibility. The Differential Scanning Calorimetry (DSC) analyses confirmed that the film prepared using the solvent casting method entrapped FUR in the amorphous state. As a solid dispersion, FUR increa…