Tipo de cambio flexible y fijación de metas inflacionarias en Chile: experiencia y aspectos resaltantes

(Disponible en idioma inglés) Los primeros cinco años del régimen de tipo de cambio flexible y la fijación de metas inflacionarias en Chile han arrojado resultados positivos. La inflación está controlada, el tipo de cambio ha evolucionado a la par de las condiciones externas, la política monetaria ha sido de tipo anticíclico y todo indica que el ciclo se ha suavizado. Aunque ha aumentado la inestabilidad del tipo de cambio, tal como cabría anticipar con un sistema flexible, lo mismo ha ocurrido en otros países de características similares. Este aumento de la inestabilidad muestra valoraciones extremas del tipo de cambio real más bajas que en el pasado y también se aprecia en otros países con sistemas cambiarios distintos. Avances importantes en la profundización del mercado de derivados, así como una menor transmisión del tipo de cambio a la inflación, han contribuido a mejorar la credibilidad y la viabilidad del actual marco de políticas, al tiempo que se minimizan los costos potenciales derivados de ese marco.

Appraisal of microcarrier suspension dynamics in shaken bioreactors

The pharmaceutical industry is at the forefront of the production of drug products using mammalian cell-based cultures, some of which rely on adherent-dependant cells. Whilst often adapted to suspension cultures, hybridoma and other cells give increased product yields when cultured attached to a substrate, such as microcarriers, resulting in smaller fermentation runs at higher densities. Microcarriers are also used in tissue engineering and cell for therapy culture. Stem cells are adherent-dependant cells and traditional 2-dimensional static cultures rely on disposable multilayer vessels, which have become the common route for stem cell expansion, although remain labour and handling intensive. Large scale production of stem cells would require the use of 3-dimensional dynamic culture methods by employing microcarrier technology, as demonstrated by Frauenschuh et al. (2007). Microcarriers consist of spherical beads with a size of 100-300 μm, and can be made of a wide variety of materials, some of them biodegradeable. Whilst most studies have focused on investigating optimal compositions of microcarrier materials, their concentration and cell culture media, little research has been undertaken on the engineering aspects of microcarrier use, such as the just-suspended speed and suspension quality. The aim of the work is to characterize the suspension dynamics of microcarriers in a cylindrical orbitally shaken bioreactor (OSR) with conical bottoms of different heights. The proposed conical bottom geometry has been proven to provide enhanced vorticity when compare to a flat bottom vessel (2). This study builds upon previous works of the research group 3-6) for a flat bottom reactor, where increases in Froude number were found to determine a mean flow transition which was found to be instrumental in determining the just-suspended speed. The dynamics of solid suspension is studied using commercially available Cytodex-3, stained with trypan for improved visual contrast. Image acquisition and computer image processing is employed to objectively measure suspension. The experimental procedure allows estimating not only the speed required for the solids to lift from the vessel bottom, but also the conditions at which a homogenous distribution of microcarriers is obtained. Preliminary results indicate that the presence of the conical bottom improves solid suspension by requiring lower agitation rates for the microcarriers to lift from the bottom completely. The critical Froude, which determines the flow type controlling the bioreactor, can be used to scale the suspension of microcarriers in OSRs. The suspension results are corroborated by mixing time measurements performed using the Dual Indicator System for Mixing Time (4), which show enhanced global mixing times when a conical bottom geometry is employed. 1. Frauenschuh, S., E. Reichmann, Y. Ibold, P. M. Goetz, M. Sittinger, and J. Ringe. A microcarrier-based cultivation system for expansion of primary mesenchymal stem cells. Biotechnology progress 2007,23,187–193. 2. Rodriguez G, Anderlei T, Micheletti, M, Ducci A Appraisal of fluid flow in a shaken bioreactor with conical bottom at different operating conditions, Chem Eng Res Des. 2016;108;186-197 3. Rodriguez G, Weheliye W, Anderlei T, Micheletti M, Yianneskis M, Ducci A. Mixing time and kinetic energy measurements in a shaken cylindrical bioreactor. Chem Eng Res Des. 2013;81:331–341. 4. Weheliye W, Yianneskis M, Ducci A. On the fluid dynamics of shaken bioreactors - flow characterization and transition. AIChE J. 2013;59:334–344. 5. Rodriguez G, Anderlei T, Micheletti M, Yianneskis M, Ducci A. On the measurement and scaling of mixing time in orbitally shaken bio- reactors. Biochem Eng J. 2014;82:10–21. 6. Pieralisi I, Rodriguez G., Micheletti M., Paglianti A., Ducci A. Microcarriers’ suspension and flow dynamics in orbitally shaken bioreactors. Chem Eng Res Des. 2016; 108;198-209

Genetic variability of Nero Lucano pig breed at IGF2, LEP, MC4R, PIK3C3, RYR1 and VRTN loci

The Nero Lucano pig is a native breed of Southern Italy which thanks to the joint action of Basilicata Region Institutions, University of Basilicata and breeders returned to populate the area of origin. In order to characterise and to monitor the variability present in the population, we genotyped 229 animals at 12 polymorphic loci located in the following genes: IGF2, LEP, MC4R, PIK3C3, RYR1 and VRTN. According to the results three loci (IGF2 209G>C, PIK3C3 2058A>G and RYR1 1843C>T) did not show variability, while the others showed genotype distributions in agreement with Hardy-Weinberg equilibrium and a minor allele frequency ranging from 0.022 for MC4R 892A to 0.479 for PIK3C3 2604T alleles. The IGF2, MC4R and VRTN loci were characterised by very low frequencies (from 0.02 to 0.05) of the alleles that are associated with favourable productive characteristics in cosmopolitan breeds.Highlights Analyses of the genetic variability of Nero Lucano pig population useful for meat production selection plans. The IGF2, MC4R and VRTN loci of Nero Lucano pig show very low frequencies of alleles associated with positive effects on meat production. The Nero Lucano pig can be considered as free from Malignant Hyperthermia, a positive result for the quality of cured meat products

Che c'importa delle torri, meglio l'atletica!

The article focuses on the editorial policy of two authoritative papers, Renmin ribao and Guangming ribao in relation with the September 11th attack to the Twin Towers. The author claims that the analysis and the position of the two papers usually mirror the Central Government’s one and that, in spite of the fact that the Islamic terrorism is a severe problem for the Chinese authorities too, they anyway tend to disagree with any initiative taken without the U.N. approval, as it happens with the case of the USA attack against Afghanistan. Gregorio points out the core elements of the ambiguity of the Chinese foreign policy in those days, as it appears in the Renmin ribao and in Guangming ribao and outlines the reasons why the Chinese try their best not to bring their relationship with America to a point of no return, at the eve of APEC summit and of the official entry of China in the WTO

Clinical, Microbiological, and Genetic Characteristics of Heteroresistant Vancomycin-Intermediate Staphylococcus aureus Bacteremia in a Teaching Hospital

The emergence of vancomycin intermediate Staphylococcus aureus (VISA) and heterogeneous VISA (hVISA) is of major concern worldwide. Our objective was to investigate the prevalence, phenotypic and molecular features of hVISA strains isolated from bacteremic patients and to determine the clinical significance of the hVISA phenotype in patients with bacteremia. A total of 104 S. aureus blood isolates were collected from a teaching hospital of Argentina between August 2009 and November 2010. No VISA isolate was recovered, and 3 out of 92 patients (3.3%) were infected with hVISA, 2 of them methicillin-resistant S. aureus (MRSA) (4.5% of MRSA). Macro Etest and prediffusion method detected 3/3 and 2/3 hVISA respectively. Considering the type of bacteremia, the three cases were distributed as follows: two patients had suffered multiple episodes of bacteremia (both hVISA strains recovered in the second episode), while only one patient had suffered a single episode of bacteremia with hVISA infection. MRSA bloodstream isolates exhibiting the hVISA phenotype were related to HA-MRSA Cordobes clone (ST5-SCCmec I-spa t149) and MRSA Argentinean pediatric clone (ST100-SCCmec IVNV-spa t002), but not to CA-MRSA-ST30-SCCmec IV-spa t019 clone that was one of the most frequent in our country. Although still relatively infrequent in our hospital, hVISA strains weresignificantly associated with multiple episodes of bacteremia ( p = 0.037) and genetically unrelated.Fil: Di Gregorio, Sabrina Noelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Perazzi, Beatriz Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Martinez Ordoñez, Andrea. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Bioquímica Clínica; ArgentinaFil: de Gregorio, Stella. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Focoli, Mónica. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Lasala, María Beatriz. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Garcia, Susana. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Vay, Carlos Alberto. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Famiglietti, Angela María Rosa. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Mollerach, Marta Eugenia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentin