Estudio de fenómenos de transferencia de calor y dinámica de fluidos mediante los métodos de Lattice Boltzmann y volúmenes finitos

El objetivo de este trabajo es investigar, implementar y comparar mediante casos de referencia, dos métodos de simulación de dinámica de fluidos: Finite Volume Method (FVM) y Lattice Boltzmann Method (LBM).El trabajo se divide en tres partes fundamentales. En la primera parte (capítulo 1) se tratan las ecuaciones que rigen la dinámica de fluidos, que son las de Navier- Stokes. Se presentan las adimensionalizaciones de las ecuaciones de Navier-Stokes para problemas de convección natural y convección forzada, identificando en cada caso los grupos adimensionales que rigen el problema. La segunda parte (capítulo 2 y 3) trata sobre los métodos numéricos LBM (Lattice Boltzmann Method) y FVM (Finite Volume Method). En cada caso se presentan el fundamento teórico sobre el que se basa y también su implementación a nivel esquemático. Por último, en la tercera parte (capítulo 4) se presenta la aplicación práctica (numérica) de LBM y FVM en problemas de referencia (los cuales sirven para validar nuevas herramientas de simulación). Se discuten los resultados obtenidos de ambos métodos y se comparan entre ellos. En los últimos capítulos se presentan las conclusiones (capítulo 5), el impacto medioambiental (capítulo 6), el presupuesto (capítulo 7) y también diferentes temas que son importantes pero han quedado fuera de alcance de este proyecto (capítulo 8). En los anexos se presentan los códigos fuentes de los programas

Evaluation of the Effectiveness of Foot-and-Mouth Disease Vaccination of Animals in the Buffer Zone of the Republic of Armenia in 2016–2020

BACKGROUND: Foot-and-mouth disease (FMD) is a high impact viral disease of livestock for which vaccines are extensively used for limiting the spread of infection. Armenia shares a border with both Turkey and Iran where FMD is endemic, making vaccination an important component of Armenia\u27s control strategy. Additionally, Armenian veterinary services utilize both passive and active monitoring for prevention control. METHODS: We sought to determine the immune status of animals vaccinated against FMD and to evaluate the effectiveness of our vaccination policy in Armenia. This was conducted in three regions including Shirak, Armavir, and Ararat Region which are located in the buffer zones that border Turkey and Iran. Through active monitoring in 2020, we studied blood serum samples from cattle and sheep using an enzyme immunoassay to determine the level of immune animals in these regions following the use of a polyvalent inactivated vaccine containing FMDV serotypes A, O, and Asia-1 that are relevant for this region. ELISA titers were assessed at 28, 90, and 180 days after vaccination in cattle of three age groups at the time of initial vaccination: 4-6 months, 6-18 months and ≥ 24 months of age with sheep of all ages. RESULTS: The 3 age groups of cattle had similarly high levels of immunity with over 90% of the cattle showing a ≥ 50% protective titer 28 days after the first vaccination. By day 90, titers in cattle from the initial 4-18-month age groups dropped below 58% across the 3 serotypes and at or below 80% for the oldest cattle ≥ 24 months. Re-vaccination of cattle at 120 days did improve protective titers but never reached the level of immunity of the first vaccination. Sheep showed a similar rapid drop to less than 50% having a ≥ 50% protective titer at 90 days emphasizing the need for continual revaccination. CONCLUSIONS: The results of this study have important implications for the current FMD vaccine policy in Armenia and improves our understanding of the rapid loss of protective titers over short periods. Since small ruminants are only vaccinated once per year and vaccination titers drop rapidly by 90 days suggests that they are vulnerable to FMD and that vaccination protocols need to be updated. Cattle should continue to be vaccinated every 3-6 months depending on their age to maintain a protective level of antibodies to protect them from FMD. More studies are needed to understand the possible role of small ruminants in the epidemiology of FMD and to evaluate revaccination at shorter intervals. These results show the concerns of rapid loss of protection to both cattle and small ruminants following 1 or more doses of commercial vaccines and that additional vaccines need to be evaluated in both groups to know how often they must be vaccinated to provide full protection. The addition of challenge studies should also be considered to better understand the level of protection as measured by serology and how it relates to protection from challenge. These results should be considered by anyone using these vaccines in cattle and sheep at longer than 3 month intervals

Doxorubicin-Induced Translocation of mtDNA into the Nuclear Genome of Human Lymphocytes Detected Using a Molecular-Cytogenetic Approach

Translocation of mtDNA in the nuclear genome is an ongoing process that contributes to the development of pathological conditions in humans. However, the causal factors of this biological phenomenon in human cells are poorly studied. Here we analyzed mtDNA insertions in the nuclear genome of human lymphocytes after in vitro treatment with doxorubicin (DOX) using a fluorescence in situ hybridization (FISH) technique. The number of mtDNA insertions positively correlated with the number of DOX-induced micronuclei, suggesting that DOX-induced chromosome breaks contribute to insertion events. Analysis of the odds ratios (OR) revealed that DOX at concentrations of 0.025 and 0.035 µg/mL significantly increases the rate of mtDNA insertions (OR: 3.53 (95% CI: 1.42–8.76, p < 0.05) and 3.02 (95% CI: 1.19–7.62, p < 0.05), respectively). Analysis of the distribution of mtDNA insertions in the genome revealed that DOX-induced mtDNA insertions are more frequent in larger chromosomes, which are more prone to the damaging action of DOX. Overall, our data suggest that DOX-induced chromosome damage can be a causal factor for insertions of mtDNA in the nuclear genome of human lymphocytes. It can be assumed that the impact of a large number of external and internal mutagenic factors contributes significantly to the origin and amount of mtDNA in nuclear genomes

Analyzing atmospheric electric field by the European SEVAN network of particle detectors

Particle detectors of the European SEVAN network located on mountain heights in Aragats (Armenia), Lomnický štít (Slovakia) and Musala (Bulgaria) are well suited for the detection of thunderstorm ground enhancements (TGEs, enhanced fluxes of electrons, gamma rays, neutrons). The modulation of charged particles flux by the electric field of the thundercloud results in a sizable change in the count rate of detectors, which measure fluxes of electrons, gamma rays, and high energy muons in the near-vertical and near-horizontal directions. The relation between electric field strength and changes of particle flux count rates is nonlinear and depends on many unknown parameters of atmospheric electric field and meteorological conditions. Nonetheless, employing extreme TGEs as a manifestation of the strong electric field in the thundercloud and by measuring fluxes of three species of secondary cosmic rays (electrons, gamma rays, and muons) by SEVAN detectors located at altitudes of ≈ 3 km we study the extreme strength of the atmospheric electric field. With the simulation of particle traversal through the electric field with CORSIKA code (https://www.iap.kit.edu/corsika/index.php, last accessed April 21, 2021), we derive a maximum potential difference in the thunderous atmosphere to be ≈ 500 MV

Estudio de fenómenos de transferencia de calor y dinámica de fluidos mediante los métodos de Lattice Boltzmann y volúmenes finitos

El objetivo de este trabajo es investigar, implementar y comparar mediante casos de referencia, dos métodos de simulación de dinámica de fluidos: Finite Volume Method (FVM) y Lattice Boltzmann Method (LBM).El trabajo se divide en tres partes fundamentales. En la primera parte (capítulo 1) se tratan las ecuaciones que rigen la dinámica de fluidos, que son las de Navier- Stokes. Se presentan las adimensionalizaciones de las ecuaciones de Navier-Stokes para problemas de convección natural y convección forzada, identificando en cada caso los grupos adimensionales que rigen el problema. La segunda parte (capítulo 2 y 3) trata sobre los métodos numéricos LBM (Lattice Boltzmann Method) y FVM (Finite Volume Method). En cada caso se presentan el fundamento teórico sobre el que se basa y también su implementación a nivel esquemático. Por último, en la tercera parte (capítulo 4) se presenta la aplicación práctica (numérica) de LBM y FVM en problemas de referencia (los cuales sirven para validar nuevas herramientas de simulación). Se discuten los resultados obtenidos de ambos métodos y se comparan entre ellos. En los últimos capítulos se presentan las conclusiones (capítulo 5), el impacto medioambiental (capítulo 6), el presupuesto (capítulo 7) y también diferentes temas que son importantes pero han quedado fuera de alcance de este proyecto (capítulo 8). En los anexos se presentan los códigos fuentes de los programas

Estudio de fenómenos de transferencia de calor y dinámica de fluidos mediante los métodos de Lattice Boltzmann y volúmenes finitos

El objetivo de este trabajo es investigar, implementar y comparar mediante casos de referencia, dos métodos de simulación de dinámica de fluidos: Finite Volume Method (FVM) y Lattice Boltzmann Method (LBM).El trabajo se divide en tres partes fundamentales. En la primera parte (capítulo 1) se tratan las ecuaciones que rigen la dinámica de fluidos, que son las de Navier- Stokes. Se presentan las adimensionalizaciones de las ecuaciones de Navier-Stokes para problemas de convección natural y convección forzada, identificando en cada caso los grupos adimensionales que rigen el problema. La segunda parte (capítulo 2 y 3) trata sobre los métodos numéricos LBM (Lattice Boltzmann Method) y FVM (Finite Volume Method). En cada caso se presentan el fundamento teórico sobre el que se basa y también su implementación a nivel esquemático. Por último, en la tercera parte (capítulo 4) se presenta la aplicación práctica (numérica) de LBM y FVM en problemas de referencia (los cuales sirven para validar nuevas herramientas de simulación). Se discuten los resultados obtenidos de ambos métodos y se comparan entre ellos. En los últimos capítulos se presentan las conclusiones (capítulo 5), el impacto medioambiental (capítulo 6), el presupuesto (capítulo 7) y también diferentes temas que son importantes pero han quedado fuera de alcance de este proyecto (capítulo 8). En los anexos se presentan los códigos fuentes de los programas

STRATEGIC DEFENCE REVIEW IN THE CONTEXT OF REFORMS

The South Caucasus region is characterized by the presence of frozen conflicts, and the activation of impending threats. For security and stability it is important that the countries in the region have adopted a diametrically different security and defense strategies and policy of joining the centers of power and allies. Continuing development of defense capabilities is the logical choice for Armenia, which follows from the aims of the state and public security, and, if necessary, even the world compulsion. To achieve these objectives Republic of Armenia carries out a process, which is called Strategic Defense Review

STRATEGIC DEFENCE REVIEW IN THE CONTEXT OF DEFENCE REFORMS

The South Caucasus region is characterized by the presence of frozen conflicts, the activation of impending threats. For security and stability problematic is the important factor that the countries in the region have adopted a diametrically different security and defense strategies, policy of joining the centers of power and allies. Continuing development of defense capabilities is a logical choice for Armenia, which follows from the aims of the state and public security, and the maintenance and, if necessary, even the world compulsion. To achieve these objectives in the Republic of Armenia is carried out the process, which called the Strategic Defense Review

Transient Luminous Events in the Lower Part of the Atmosphere Originated in the Peripheral Regions of a Thunderstorm

We present and discuss transient luminous events (TLEs) in the lower atmosphere, observed during large disturbances of the near-surface electric fields (NSEF) and coinciding with large enhancements of the particle fluxes (thunderstorm ground enhancements&mdash;TGEs). Despite large distances from the strongest electric field region, the maximum energy of TGE particles on 22 and 25 May 2018 reaches &asymp;40 MeV. Thus, the accelerating electric field reaches &asymp;2.0 keV/cm far from the zone of the strong lightning activity on the periphery of the storm. Light glows appearing simultaneously in the skies may be due to the local charge rearrangement generating a small illuminating discharge without initiating the lightning flash. This type of charge rearrangement does not lower the potential difference in the cloud, allowing the electron accelerator to operate and send particle fluxes in the direction of the earth&rsquo;s surface