Choice of the initial antiretroviral treatment for HIV-positive individuals in the era of integrase inhibitors

BACKGROUND: We aimed to describe the most frequently prescribed initial antiretroviral therapy (ART) regimens in recent years in HIV-positive persons in the Cohort of the Spanish HIV/AIDS Research Network (CoRIS) and to investigate factors associated with the choice of each regimen. METHODS: We analyzed initial ART regimens prescribed in adults participating in CoRIS from 2014 to 2017. Only regimens prescribed in >5% of patients were considered. We used multivariable multinomial regression to estimate Relative Risk Ratios (RRRs) for the association between sociodemographic and clinical characteristics and the choice of the initial regimen. RESULTS: Among 2874 participants, abacavir(ABC)/lamivudine(3TC)/dolutegavir(DTG) was the most frequently prescribed regimen (32.1%), followed by tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC)/elvitegravir(EVG)/cobicistat(COBI) (14.9%), TDF/FTC/rilpivirine (RPV) (14.0%), tenofovir alafenamide (TAF)/FTC/EVG/COBI (13.7%), TDF/FTC+DTG (10.0%), TDF/FTC+darunavir/ritonavir or darunavir/cobicistat (bDRV) (9.8%) and TDF/FTC+raltegravir (RAL) (5.6%). Compared with ABC/3TC/DTG, starting TDF/FTC/RPV was less likely in patients with CD4100.000 copies/mL. TDF/FTC+DTG was more frequent in those with CD4100.000 copies/mL. TDF/FTC+RAL and TDF/FTC+bDRV were also more frequent among patients with CD4<200 cells//muL and with transmission categories other than men who have sex with men. Compared with ABC/3TC/DTG, the prescription of other initial ART regimens decreased from 2014-2015 to 2016-2017 with the exception of TDF/FTC+DTG. Differences in the choice of the initial ART regimen were observed by hospitals' location. CONCLUSIONS: The choice of initial ART regimens is consistent with Spanish guidelines' recommendations, but is also clearly influenced by physician's perception based on patient's clinical and sociodemographic variables and by the prescribing hospital location

Simulación numérica de recuperación de petróleo en un tubo de combustión

Se propone un conjunto de reacciones que permiten modelar los procesos de rompimiento de cadenas de hidrocarburos y combustión en un experimento de tubo de combustión. El modelo se usó para reproducir los frentes de combustión

Understanding the relationship between Mycobacterium bovis spoligotypes from cattle in Latin American Countries

Spoligotyping is the most frequently used method for genotyping isolates of Mycobacterium bovis worldwide. In the current work, we compared spoligotypes from 1684 M. bovis isolates from Argentina (816), Brazil (412), Chile (66), Mexico (274) and Venezuela (116), obtained from cattle, humans, pigs, wild boars, farmed deer, goats, buffaloes, cats, and wild animals. A total of 269 different spoligotypes were found: 142 (8.4%) isolates presented orphan spoligotypes, whereas 1542 (91.6%) formed 113 different clusters. In cattle, SB0140 was the most representative spoligotype with 355 (24.6%) isolates, followed by SB0121 with 149 (10.3%) isolates. Clustering of spoligotypes ranged from 95.2% in Argentina to 85.3% in Mexico. Orphan spoligotypes were also variable, ranging from 23.7% in Mexico to 4.1% in Brazil. A large proportion of spoligotypes were common to the neighboring countries Argentina, Brazil and Chile. In conclusion, despite the diversity of spoligotypes found in the five countries studied, there are major patterns that predominate in these neighboring countries. These clusters may reflect a long-lasting active transmission of bovine tuberculosis or common historical origins of infection.Instituto de BiotecnologíaFil: Zumarraga, Martin Jose. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Arriaga, Camila. Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias. Centro Nacional de Investigación Disciplinaria en Microbiología Animal; MéxicoFil: Barandiaran, Soledad. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Cobos-Marín, Laura. Universidad Nacional Autónoma de México. Facultad de Medicina Veterinaria y Zootecnia; MéxicoFil: de Waard, Jacobus. Universidad Central de Venezuela. Instituto de Biomedicina. Laboratorio de Tuberculosis; VenezuelaFil: Estrada-Garcia, Iris. Instituto Politécnico Nacional. Escuela Nacional de Ciencias Biológicas; MéxicoFil: Figueiredo, Telma. Instituto Oswaldo Cruz. Laboratorio de Biologia Molecular Aplicada em Micobacterias; BrasilFil: Figueroa, Alvaro. Universidad Austral de Chile. Facultad de Ciencias. Instituto de Bioquímica; ChileFil: Gimenez, Francisco. Universidad Central de Venezuela. Instituto de Biomedicina. Laboratorio de Tuberculosis; VenezuelaFil: Gomes, Harrison M. Instituto Oswaldo Cruz. Laboratorio de Biologia Molecular Aplicada em Micobacterias; BrasilFil: Gonzalez-y-Merchand, Jorge A. Instituto Politécnico Nacional. Escuela Nacional de Ciencias Biológicas; MéxicoFil: Macias, Analía. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Milián-Suazo, Feliciano. Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias. Centro Nacional de Investigación Disciplinaria en Fisiología y Mejoramiento Animal; MéxicoFil: Rodríguez, Cesar Alejandro Rosales. Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia. Departamento de Medicina Veterinária Preventiva e Saúde Animal; BrasilFil: Santillán, Marco Antonio. Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias. Centro Nacional de Investigación Disciplinaria en Fisiología y Mejoramiento Animal; MéxicoFil: Suffys, Philip Noel. Instituto Oswaldo Cruz. Laboratorio de Biologia Molecular Aplicada em Micobacterias; BrasilFil: Trangoni, Marcos David. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Zarraga, Ana Maria. Universidad Austral de Chile. Facultad de Ciencias. Instituto de Bioquímica y Microbiología; ChileFil: Cataldi, Angel Adrian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentin

Apparent viscosity and particle pressure of a concentrated suspension of non-Brownian hard spheres near the jamming transition

We consider the steady shear flow of a homogeneous and dense assembly of hard spheres suspended in a Newtonian viscous fluid. In a first part, a mean-field approach based on geometric arguments is used to determine the viscous dissipation in a dense isotropic suspension of smooth hard spheres and the hydrodynamic contribution to the suspension viscosity. In a second part, we consider the coexistence of transient solid clusters coupled to regions with free flowing particles near the jamming transition. The fraction of particles in transient clusters is derived through the Landau-Ginzburg concepts for first-order phase transition with an order parameter corresponding to the proportion of “solid” contacts. A state equation for the fraction of particle-accessible volume is introduced to derive the average normal stresses and a constitutive law that relates the total shear stress to the shear rate. The analytical expression of the average normal stresses well accounts for numerical or experimental evaluation of the particle pressure and non-equilibrium osmotic pressure in a dense sheared suspension. Both the friction level between particles and the suspension dilatancy are shown to determine the singularity of the apparent shear viscosity and the flow stability near the jamming transition. The model further predicts a Newtonian behavior for a concentrated suspension of neutrally buoyant particles and no shear thinning behavior in relation with the shear liquefaction of transient solid clusters

Bridging the distance: Managing cross-border knowledge holders

This article examines the micro-level operational difficulties for multinational corporations (MNCs) to generate value from its highly geographically dispersed cross-border knowledge and studies the strategies for overcoming them. Using China as the research context, we identify key geographical, institutional and cultural features of cross-border knowledge holders and examine the dimensions of distance that separates them. We then link these dimensions to the conditions that facilitate cross-border knowledge building processes. In doing so, we propose a conceptual model for overcoming these context-specific knowledge management barriers. Copyright Springer Science + Business Media, Inc. 2006Cross-border knowledge management, Knowledge holders, Management barriers, China,