ANÁLISIS DE LA VARIACIÓN SOMACLONAL EN DOS ESPECIES DE AGAVE REGENERADAS IN VITRO

Plant tissue culture has been shown to be an efficient technique for the propagation of diverse Agave species using different in vitro regeneration processes. However, it has been demonstrated that genetic changes can occur in plants regenerated under these schemes, also called somaclonal variation. Objective: the objective of this study was to determine the genetic fidelity of plantlets regenerated from three different explants (mature zygotic embryonic axis, in vitro plantlet meristematic zone, and ex vitro plantlet meristematic zone) using two pathways of micropropagation (direct and indirect organogenesis) of A. salmiana and A. marmorata. Methodology: somaclonal variation of the obtained clones was evaluated using different DNA markers, such as anchored simple inter-sequence repeat (ASSR) and random amplified polymorphic DNA (RAPD). Results: the results show that only in those clones that undergo a callus phase and, consequently, indirect organogenesis, somaclonal variation was observed. In contrast, those clones obtained by direct organogenesis were genetically stable, it means not polymorphic bands were observed. Implications: it was achieved an efficient propagation protocol for A. salmiana and A. marmorata, maintaining genetic stability of regenerated plantlets as well as a possible alternative for genetic improvement by observing somaclonal variation via indirect organogenesis in both evaluated species. Conclusions: in this research, the micropropagation pathway (direct and indirect organogenesis) was the determining factor to maintain or not the genetic fidelity of the regenerated plants in both species of Agave used.Plant tissue culture has been shown to be an efficient technique for the propagation of diverse Agave species using different in vitro regeneration processes. However, it has been demonstrated that genetic changes can occur in plants regenerated under these schemes, also called somaclonal variation. Objective: the objective of this study was to determine the genetic fidelity of plantlets regenerated from three different explants (mature zygotic embryonic axis, in vitro plantlet meristematic zone, and ex vitro plantlet meristematic zone) using two pathways of micropropagation (direct and indirect organogenesis) of A. salmiana and A. marmorata. Methodology: somaclonal variation of the obtained clones was evaluated using different DNA markers, such as anchored simple inter-sequence repeat (ASSR) and random amplified polymorphic DNA (RAPD). Results: the results show that only in those clones that undergo a callus phase and, consequently, indirect organogenesis, somaclonal variation was observed. In contrast, those clones obtained by direct organogenesis were genetically stable, it means not polymorphic bands were observed. Implications: it was achieved an efficient propagation protocol for A. salmiana and A. marmorata, maintaining genetic stability of regenerated plantlets as well as a possible alternative for genetic improvement by observing somaclonal variation via indirect organogenesis in both evaluated species. Conclusions: in this research, the micropropagation pathway (direct and indirect organogenesis) was the determining factor to maintain or not the genetic fidelity of the regenerated plants in both species of Agave used.UNIVERSIDAD AUTONOMA DEL ESTADO DE MEXIC

Bioengineered in vitro skeletal muscles as new tools for muscular dystrophies preclinical studies

Muscular dystrophies are a group of highly disabling disorders that share degenerative muscle weakness and wasting as common symptoms. To date, there is not an effective cure for these diseases. In the last years, bioengineered tissues have emerged as powerful tools for preclinical studies. In this review, we summarize the recent technological advances in skeletal muscle tissue engineering. We identify several ground-breaking techniques to fabricate in vitro bioartificial muscles. Accumulating evidence shows that scaffold-based tissue engineering provides topographical cues that enhance the viability and maturation of skeletal muscle. Functional bioartificial muscles have been developed using human myoblasts. These tissues accurately responded to electrical and biological stimulation. Moreover, advanced drug screening tools can be fabricated integrating these tissues in electrical stimulation platforms. However, more work introducing patient-derived cells and integrating these tissues in microdevices is needed to promote the clinical translation of bioengineered skeletal muscle as preclinical tools for muscular dystrophies

Influence of SO2 on CO2 storage for CCS technology: Evaluation of CO2/SO2 co-capture

In this work, we determined the influence of SO2 as an impurity in anthropogenic CO2 on carbon capture and storage (CCS) technology. We evaluated the impact on selected injection and storage parameters and the Joule-Thomson coefficient to assess the safety of long-term geological storage of CO2. For this purpose, we obtained new pressure-density-temperature-composition, vapor-liquid-equilibrium, and pressure-speed of sound-temperature-composition experimental data for CO2-rich mixtures containing SO2. To increase the general understanding of the impact of SO2, the compositions cover possible co-capture mixtures, SO2-enriched mixtures, and mixtures similar to industrial emissions. Temperatures and pressures were based on relevant geological storage site values. Our experimental results were used to validate the EOS-CG and PC-SAFT equations of state (EoSs) for CO2 + SO2 under the studied CCS conditions. On the understanding that the chemical reactivity effects due to SO2 have not been considered, we concluded that the presence of SO2 is profitable in most of the studied aspects, especially in the case of shallow reservoirs, and that CO2/SO2 co-capture may be considered as an alternative approach to reduce the costs of CO2 purification. Based on the assessment of the impact of 5 mol% SO2 in the injected fluid in seven saline aquifers, we determined that the reservoirs that would receive the most benefit were Sleipner, Nagaoka and Frio

Influence of methane and carbon monoxide in the volumetric behaviour of the anthropogenic CO2: Experimental data and modelling in the critical region

Density measurements of the systems CO 2 + CH 4 at T = 304.21 K and CO 2 + CO at T = 304.21 and 308.15 K were carried out at pressures and compositions of interest in the process of transport and storage of CO 2 (CCS technology): P = 0.1 to 20 MPa, and xCO 2 ≥0.97. From the experimental P––T –xCO 2 data, we have studied the dependence of the isothermal compressibility, the excess molar volume, and the par- tial molar volume of the solute with composition, pressure and temperature within the critical region. We have modelled the volumetric behaviour of these systems with Peng–Robinson, PC-SAFT and GERG Equations of State, thus validating these equations under the conditions considered. Furthermore, we have confirmed the weakly attractive behaviour of these systems by performing a study of the interac- tions between solvent molecules, CO 2 , and those of the solute, CO or CH 4 , using the Krichevskii Function concept and the Kirkwood–Buff Theory. Finally, we have quantified the influence of small amounts of CH 4 and CO in the transport of anthropogenic CO 2 through several normalized parameters, related to the design and operation of the fluid transport process

"San Andrés jugaba a la taba, tanto perdía como ganaba". Estrategias sociales ante la suerte en Colmenar Viejo

In Colmenar, a town near Madrid, the kids played with the «taba» and distributed fictitious social positions. On 30th November and 13th December the meo play with the «taba», they bet money and it could be possible a change in the social positions. There are different groups of players at the different places, times and bets. Essentially in the game one person is against people. That is a possible way of the social change. The risk is reduced by a series of strategies, related to the occupation of the game's roles and related to the integration into the groups too.En Colmenar, una población madrileña, para los niños, el juego de la taba distribuía distintas «posiciones» sociales; para los adultos, sin embargo, y en determinados días del año, San Andrés (30 de noviembre) y Santa Lucía (13 de diciembre), es un juego de apuestas que hace circular el dinero y pudiera hacer posible una movilidad social. Se distinguen diferentes grupos de jugadores según el lugar, la hora de juego y la cuantía de la apuesta. El juego enfrenta en esencia a uno contra todos. U na de las vías teóricas para la movilidad social. El riesgo que eso comporta es reducido por medio de una serie de estrategias, relativas tanto a la adopción de uno u otro rol en el juego como a la formación de grupos

High-pressure speed of sound in pure CO2 and in CO2 with SO2 as an impurity using methanol as a doping agent

Reliable speed of sound, c, values in CO2- rich mixtures and pure CO2 are required for carbon capture and storage (CCS) technology but are difficult to determine, particularly at relatively high frequencies. We tested the suitability of methanol as doping agent to obtain accurate c values in CCS systems at 5 MHz. We measured c in seven CO2-rich, CO2 + methanol mixtures between 263.15 and 323.15 K and up to 196.30 MPa, and we extrapolated the values to obtain c in pure CO2. Additionally, we measured c from 263.15 to 373.19 K and up to 190.10 MPa in two CO2-rich, CO2 + SO2 mixtures with the same SO2 composition, which is of interest for CCS, with one mixture doped with methanol. We compared our results for pure CO2 with the literature and the Span and Wagner equation of state (EoS). We validated the PC-SAFT EoS and the modeling with the REFPROP 9 software for the mixtures by comparing the predicted values with our experimental data under the studied conditions. We conclude that methanol is a suitable doping agent to measure c in pure CO2 and CO2-rich mixtures. For the CO2 + SO2 mixtures, the effect of methanol on the experimental values is small and negligible for modeling

The role of impulsivity in dropout from treatment for cigarette smoking

AbstractImpulsivity is a variable that has been associated with drug use. This study analyzes impulsivity from two different paradigms, one considering it as a trait and the other based on its behavioral correlates, such as disinhibition and impulsive decision-making in the treatment prognosis (maintain abstinence, relapse and dropout) of smokers after outpatient treatment. The participants in the study were 113 smokers who requested treatment for nicotine addiction. They were assigned to three groups according to whether or not they remained abstinent one month after beginning treatment; thus, group 1 was abstinent, group 2 had relapsed, and group 3 had dropped out of treatment. The participants filled out the Semi-structured Interview for Smokers, the Fargerström Test for Nicotine Dependence, the Temperament and Character Inventory-Revised (TCI-R) and the Delay Discounting Task (DDT). The Delay Discounting variable presents lower scores in the dropout group than in the relapse and abstinent groups, with the highest scores in the relapse group. Differences were also found on the Harm Avoidance (HA) variable, with lower scores in the dropout group compared to the relapse group. The importance of these results lies in the consideration of the smoker’s personality profile in order to prevent both dropout and relapse