Applications of CFD for Process Safety

Nowadays, the statistical studies have revealed that major accidents (MA) are frequent in diverse industries, which has originated the development of strategies and normative focussed in foreseeing and preventing these. Thus, the process safety is in continuous improvement. The experimental studies in this field result in situations of high risks and are usually expensive. Therefore, the implementation of developments as the computational fluid dynamics (CFD) techniques is now applied, and has proven to be advantageous. In this work, CFD models for pool and jet fires are presented, as these kinds of fires are usually involved in major accidents. The results of the CFD models show orders of magnitude and behaviors in good agreement with experimental observations found in literature. The outputs of the simulations showed values of around 500 and 1400 K for the pool fires; while the jet fires predictions were of temperatures around 500 and 1050 K. Furthermore, the information obtained by these models can be used in order to develop safety plans to diminish risks in the facilities designs, safe zones and emergency exit routes

Adenosine Monophosphate (AMP)-Activated Protein Kinase: A New Target for Nutraceutical Compounds

Adenosine monophosphate-activated protein kinase (AMPK) is an important energy sensor which is activated by increases in adenosine monophosphate (AMP)/adenosine triphosphate (ATP) ratio and/or adenosine diphosphate (ADP)/ATP ratio, and increases different metabolic pathways such as fatty acid oxidation, glucose transport and mitochondrial biogenesis. In this sense, AMPK maintains cellular energy homeostasis by induction of catabolism and inhibition of ATP-consuming biosynthetic pathways to preserve ATP levels. Several studies indicate a reduction of AMPK sensitivity to cellular stress during aging and this could impair the downstream signaling and the maintenance of the cellular energy balance and the stress resistance. However, several diseases have been related with an AMPK dysfunction. Alterations in AMPK signaling decrease mitochondrial biogenesis, increase cellular stress and induce inflammation, which are typical events of the aging process and have been associated to several pathological processes. In this sense, in the last few years AMPK has been identified as a very interesting target and different nutraceutical compounds are being studied for an interesting potential effect on AMPK induction. In this review, we will evaluate the interaction of the different nutraceutical compounds to induce the AMPK phosphorylation and the applications in diseases such as cancer, type II diabetes, neurodegenerative diseases or cardiovascular diseases

CFD Modelling of Coupled Multiphysics-Multiscale Engineering Cases

Many of the engineering problems have multiphysics and multiscale nature. Non-isothermal flows, stirred reactors, turbulent mixing and membrane filtration, are prevalent cases in which the coupling of several physics phenomena is required for the adequate prediction of overall behaviors. Also, a multiscale analysis, where the same phenomenon is analyzed at different scales, can lead to better understanding of the phenomena, which can be used in optimization and to provide adequate scale-up methodologies. Studies incorporating both multiscale and multiphysics analysis are rarely addressed in literature; in fact, these kinds of problems will be the research challenge in the next years. Computer fluid dynamics (CFD) techniques have shown to be promising to deal with these kinds of systems. In this chapter, these are used to implement a multiscale analysis of the hydrodesulphurization (HDS) process for light gas-oil (LGO). The aforementioned is carried out by the analysis of mass an energy transport at: (1) microporous (MP) scale, (2) pseudo-homogeneous catalyst (PHC) scale, and by analysis of (3) momentum and mass transport at reactor scale (RS). In addition, a particular discussion is made regarding the proper establishment of the model, its validation, the use of different boundary conditions, its justification; and the dependence of solutions of parameters and initial and boundary conditions

CFD Analysis of BED Textural Characteristics on TBR Behavior: Hydrodynamics and Scaling-up

In recent years, CFD has played an important role in the understanding and design of TBR’s. In this work, through CFD with Eulerian approach, a three-phase heterogeneous reactor model was developed, were the accuracy of Interfacial Momentum Exchange Model (IMEM) for the gas-solid interaction, the effect of a more detailed catalytic bed geometry description, and the pellet shape over TBR hydrodynamics of two fluid phases interacting with the solid phase was studied. Then, a second model was developed, where the validated hy- drodynamic model was coupled with mass transport for an HDS process of light gasoil. Additionally, in order to insight into the scaling up process of a TBRs, the proposed columns behaviors were compared against lit- erature columns using four different ways, and it was found that the best predictions were obtained when the models’ holdup were equaled to those evaluated in literature columns. Since in reliable literature deviations in pressure drop predictions of around 30% can be found, the model results show significant improvement against literature, achieving 5 times better accuracy in predicting pressure drops, and 50% improvement in holdup prediction; the coupled model reproduces the same conversion values compared with literature data, and predicts conversions with 95% accurac

NLRP3-inflammasome inhibition prevents high fat and high sugar diets-induced heart damage through autophagy induction

The NLRP3-inflammasome complex has emerged as an important component of inflammatory processes in metabolic dysfunction induced by high-caloric diets. In this study, we investigate the molecular mechanisms by which NLRP3 inhibition may attenuate diet-induced cardiac injury. Here we show the cardiac damage induced by high sugar diet (HSD), high fat diet (HFD) or high sugar/fat diet (HSFD) over 15 weeks. Genetic ablation of NLRP3 protected against this damage by autophagy induction and apoptotic control. Furthermore, NLRP3 inhibition by the selective small molecule MCC950 resulted in similar autophagy induction and apoptotic control in hearts after diets. These data were reproduced in THP-1 cells treated with MCC950 and cultured in media supplemented with serum from mice dosed with MCC950 and fed with diets. NLRP3 inhibition exerted beneficial metabolic, and autophagic adaptations in hearts from obesogenic diets. The inhibition of NLRP3 activation may hold promise in the treatment of metabolic and cardiovascular diseases.Junta de Andalucía CTS113Junta de Andalucia PI-0036-201

EVALUATION OF TWO EMBRYO CRYOPRESERVATION METHODS IN LLAMA ON THE IN VIVO E IN VITRO EMBRYONIC SURVIVAL RATES

El objetivo del estudio fue evaluar el efecto de dos métodos de criopreservación sobre la supervivencia in vivo e in vitro de embriones de llama. Se recuperaron 73 embriones en estadio de blastocisto eclosionado mediante una técnica no quirúrgica a los 6.5 días post servicio en llamas superestimuladas. Las llamas receptoras se distribuyeron aleatoriamente en grupo Control (n = 14), de vitrificación (n=30) y de congelación lenta (n=29). Para la vitrificación, los embriones fueron expuestos a la solución de vitrificación (SV) conteniendo 20% Glicerol + 20% Etilenglicol + 0.5M Sucrosa + 10% suero fetal bovino (SFB) + 50 μg/ml sulfato de gentamicina, y sumergidos en nitrógeno líquido dentro de pajillas de 0.25 ml. Para la congelación lenta, los embriones fueron expuestos a fosfato buffer salino (PBS) con 1.5 M de Etilenglicol + 10% de SFB + 50 μg/ml de sulfato de gentamicina, aspirados en pajillas de 0.25 ml, y enfriados a una tasa de descenso de 0.12 °C/min hasta 5 °C y, luego, en la boca del tanque de nitrógeno, se continuó el descenso a una tasa de 5 °C /min hasta -20 °C por 5 min, y luego se sumergieron en el nitrógeno líquido. En la descongelación se utilizaron soluciones de dilución conteniendo dos concentraciones de sucrosa: 0.5 M y 0.2 M para congelación lenta y 0.25 M y 0.12 M para vitrificación. Se realizó una evaluación in vivo a todos los embriones del grupo control y al 50% de los embriones de los dos grupos experimentales, mediante transferencia directa a hembras receptoras previamente sincronizadas. El diagnóstico de preñez se llevó a cabo por ecografía transrectal a los 20 y 30 días. La preñez fue de 4/13, 2/12 y 0/11 para las receptoras de los grupos Control, Vitrificados y Congelación lenta, respectivamente, sin diferencia estadística. Para la evaluación in vitro, los embriones criopreservados fueron cultivados en PBS + 20% SFB, en una atmósfera compuesta por 5% de CO2, 20% de O2 y 75% de N2, durante 1 h a 39 °C, y se observó su re-expansión mediante la observación de su morfología. Se obtuvo 75.0% (9/12) de re-expansión en embriones vitrificados y 57.1% (4/7) en embriones congelados lentamente (4/7), sin diferencia significativa. Los resultados permiten concluir que la vitrificación podría ser el método adecuado para la criopreservación de embriones de llama.The aim of the study was to evaluate in llama embryosthe effect of twocryopreservation methods on the in vivo and in vitro survival rate. Seventy three hatchedblastocysts were recovered by a non-surgical technique at day 6.5 after mating fromsuperstimulated llamas. Receptors were randomly allocated to a control group (n=14),vitrification (n=30) and slow freezing (n=29). On vitrification, embryos were exposed to avitrification solution (VS) containing 20% Glycerol + 20% Ethylene glycol + 0.5 M Sucrose+ 10% fetal calf serum (FCS) + 50 μg/ml gentamicin sulfate, and then plunged into liquidnitrogen in 0.25 ml straws. On the slow freezing, embryos were exposed to phosphatebuffer saline (PBS) with 1.5 M Ethylene glycol + 10% FCS + 50 μg/ml gentamicin sulfate,loaded in 0.25 ml straws, and cooled at a rate of 0.12 °C/min to 5 °C. Then, furthertemperature decrease at 5 °C /min rate, to -20 °C, for 5 min at the mouth of the nitrogentank; finally straws were plunged into liquid nitrogen. For thawing, two dilution solutionswere used composed of two sucrose concentrations: 0.5 M and 0.2 M for slow freezing,and 0.25 M and 0.12 M for vitrification. An in vivo evaluation was performed in allembryos of the control group and in 50% of the experimental groups by direct transferinto previously synchronized female recipients. Pregnancy diagnosis was carried out bytransrectal ultrasound evaluation at 20 and 30 days. Pregnancy was in 4/13, 2/12, and 0/11 in recipients from control, vitrification and slow freezing groups respectively, withoutsignificant difference. For the in vitro evaluation cryopreservated embryos were culturedin PBS + 20% FCS under atmosphere compose of 5% CO2, 20% O2, and 75% N2 at 39 °C for1 h, then reexpansion was recorded by morphological characteristics. Embryo reexpansionwas 75% (9/12) in vitrified embryos and 57.1% (4/7) in slow freezing embryos, and withoutsignificant difference. It was concluded that vitrification could be a suitable method forllama embryo cryopreservation

Oxidative Stress Correlates with Headache Symptoms in Fibromyalgia: Coenzyme Q10 Effect on Clinical Improvement

This is an open-access article distributed under the terms of the Creative Commons Attribution License.[Background]: Fibromyalgia (FM) is a chronic pain syndrome with unknown etiology and a wide spectrum of symptoms such as allodynia, debilitating fatigue, joint stiffness and migraine. Recent studies have shown some evidences demonstrating that oxidative stress is associated to clinical symptoms in FM of fibromyalgia. We examined oxidative stress and bioenergetic status in blood mononuclear cells (BMCs) and its association to headache symptoms in FM patients. The effects of oral coenzyme Q 10 (CoQ 10) supplementation on biochemical markers and clinical improvement were also evaluated. [Methods]: We studied 20 FM patients and 15 healthy controls. Clinical parameters were evaluated using the Fibromyalgia Impact Questionnaire (FIQ), visual analogues scales (VAS), and the Headache Impact Test (HIT-6). Oxidative stress was determined by measuring CoQ 10, catalase and lipid peroxidation (LPO) levels in BMCs. Bioenergetic status was assessed by measuring ATP levels in BMCs. [Results]: We found decreased CoQ 10, catalase and ATP levels in BMCs from FM patients as compared to normal control (P<0.05 and P<0.001, respectively) We also found increased level of LPO in BMCs from FM patients as compared to normal control (P<0.001). Significant negative correlations between CoQ 10 or catalase levels in BMCs and headache parameters were observed (r = -0.59, P<0.05; r = -0.68, P<0.05, respectively). Furthermore, LPO levels showed a significant positive correlation with HIT-6 (r = 0.33, P<.05). Oral CoQ 10 supplementation restored biochemical parameters and induced a significant improvement in clinical and headache symptoms (P<0.001). [Discussion]: The results of this study suggest a role for mitochondrial dysfunction and oxidative stress in the headache symptoms associated with FM. CoQ10 supplementation should be examined in a larger placebo controlled trial as a possible treatment in FM.This work has been supported by IV Plan Propio de Investigación (University of Seville, ref. 2010/00000453), FIS PI10/00543 grant, FIS EC08/00076 grant, Ministerio de Sanidad, Spain and Fondo Europeo de Desarrollo Regional (FEDER-Unión Europea), SAS 111242 grant, Servicio Andaluz de Salud-Junta de Andalucía, Proyecto de Investigación de Excelencia de la Junta de Andalucía CTS-5725 and Federación Andaluza de Fibromialgia y Fatiga Crónica (ALBA Andalucía).Peer Reviewe

Chiapas : entre el autoritarismo y la transición democrática, desde Acteal hasta el diálogo EZLN y sociedad civil

Obra cuya intención es dar cuenta de los diversos actores sociales involucrados en el conflicto de Chiapas, a nivel político, económico y sociocultural. El texto recupera un taller de análisis de coyuntura sobre el tema, realizado en agosto de 1998.ITESO, A.C

Epstein-Barr-virus-positive large B-cell lymphoma associated with breast implants: an analysis of eight patients suggesting a possible pathogenetic relationship.

Breast implant anaplastic large cell lymphoma (ALCL) is a T-cell neoplasm arising around textured breast implants that was recognized recently as a distinct entity by the World Health Organization. Rarely, other types of lymphoma have been reported in patients with breast implants, raising the possibility of a pathogenetic relationship between breast implants and other types of lymphoma. We report eight cases of Epstein-Barr virus (EBV)-positive large B-cell lymphoma associated with breast implants. One of these cases was invasive, and the other seven neoplasms were noninvasive and showed morphologic overlap with breast implant ALCL. All eight cases expressed B-cell markers, had a non-germinal center B-cell immunophenotype, and were EBV+ with a latency type III pattern of infection. We compared the noninvasive EBV+ large B-cell lymphoma cases with a cohort of breast implant ALCL cases matched for clinical and pathologic stage. The EBV+ large B-cell lymphoma cases more frequently showed a thicker capsule, and more often were associated with calcification and prominent lymphoid aggregates outside of the capsule. The EBV+ B-cell lymphoma cells were more often arranged within necrotic fibrinoid material in a layered pattern. We believe that this case series highlights many morphologic similarities between EBV+ large B-cell lymphoma and breast implant ALCL. The data presented suggest a pathogenetic role for breast implants (as well as EBV) in the pathogenesis of EBV+ large B-cell lymphoma. We also provide some histologic findings useful for distinguishing EBV+ large B-cell lymphoma from breast implant ALCL in this clinical setting