Flame fronts in Supernovae Ia and their pulsational stability

The structure of the deflagration burning front in type Ia supernovae is considered. The parameters of the flame are obtained: its normal velocity and thickness. The results are in good agreement with the previous works of different authors. The problem of pulsation instability of the flame, subject to plane perturbations, is studied. First, with the artificial system with switched-off hydrodynamics the possibility of secondary reactions to stabilize the front is shown. Second, with account of hydrodynamics, realistic EOS and thermal conduction we can obtain pulsations when Zeldovich number was artificially increased. The critical Zeldovich numbers are presented. These results show the stability of the flame in type Ia supernovae against pulsations because its effective Zeldovich number is small.Comment: 12 pages, 11 figure

A Model for Multidimensional Delayed Detonations in SN Ia Explosions

We show that a flame tracking/capturing scheme originally developed for deflagration fronts can be used to model thermonuclear detonations in multidimensional explosion simulations of type Ia supernovae. After testing the accuracy of the front model, we present a set of two-dimensional simulations of delayed detonations with a physically motivated off-center deflagration-detonation-transition point. Furthermore, we demonstrate the ability of the front model to reproduce the full range of possible interactions of the detonation with clumps of burned material. This feature is crucial for assessing the viability of the delayed detonation scenario.Comment: 7 pages, accepted by A&

Automatic extraction of faults and fractal analysis from remote sensing data

Object-based classification is a promising technique for image classification. Unlike pixel-based methods, which only use the measured radiometric values, the object-based techniques can also use shape and context information of scene textures. These extra degrees of freedom provided by the objects allow the automatic identification of geological structures. In this article, we present an evaluation of object-based classification in the context of extraction of geological faults. Digital elevation models and radar data of an area near Lake Magadi (Kenya) have been processed. We then determine the statistics of the fault populations. The fractal dimensions of fault dimensions are similar to fractal dimensions directly measured on remote sensing images of the study area using power spectra (PSD) and variograms. These methods allow unbiased statistics of faults and help us to understand the evolution of the fault systems in extensional domains. Furthermore, the direct analysis of image texture is a good indicator of the fault statistics and allows us to classify the intensity and type of deformation. We propose that extensional fault networks can be modeled by iterative function system (IFS)

EC08-1488 Drinking Water Treatment: What You Need to Know When Selecting Water Treatment Equipment

This 2008 NebGuide explores household water quality and treatment options and can help consumers select a treatment system suited to a particular situation

G08-1491 Drinking Water Treatment: Water Softening (Ion Exchange)

The presence of calcium (Ca) and/or magnesium (Mg) in water results in water being considered hard. Calcium and magnesium ions in water react with heat, metallic plumbing, and chemical agents such as detergents to decrease the effectiveness of nearly any cleaning task. Hard water can be softened using an ion exchange softening process. This 2008 guide discusses the ion exchange water softening process and related equipment used for household water treatment

Josephson tunnel junctions with nonlinear damping for RSFQ-qubit circuit applications

We demonstrate that shunting of Superconductor-Insulator-Superconductor Josephson junctions by Superconductor-Insulator-Normal metal (S-I-N) structures having pronounced non-linear I-V characteristics can remarkably modify the Josephson dynamics. In the regime of Josephson generation the phase behaves as an overdamped coordinate, while in the superconducting state the damping and current noise are strikingly small, that is vitally important for application of such junctions for readout and control of Josephson qubits. Superconducting Nb/AlO${_x}$/Nb junction shunted by Nb/AlO${_x}$/AuPd junction of S-I-N type was fabricated and, in agreement with our model, exhibited non-hysteretic I-V characteristics at temperatures down to at least 1.4 K.Comment: 4 pages incl. 3 figure

Can Deflagration-Detonation-Transitions occur in Type Ia Supernovae?

The mechanism for deflagration-detonation-transition (DDT) by turbulent preconditioning, suggested to explain the possible occurrence of delayed detonations in Type Ia supernova explosions, is argued to be conceptually inconsistent. It relies crucially on diffusive heat losses of the burned material on macroscopic scales. Regardless of the amplitude of turbulent velocity fluctuations, the typical gradient scale for temperature fluctuations is shown to be the laminar flame width or smaller, rather than the factor of thousand more required for a DDT. Furthermore, thermonuclear flames cannot be fully quenched in regions much larger than the laminar flame width as a consequence of their simple ``chemistry''. Possible alternative explosion scenarios are briefly discussed.Comment: 8 pages, uses aastex; added references. Accepted by ApJ Letter

Influence of Gut Microbiome on Obesity in Western-Style Dietary Practices Versus Other Diets: A Systematic Review

BACKGROUND: The human gut is home to a microbiome that has a complex relationship to human health. Like the human genome project, microbiome is catching the attention of researchers who seek new methods to combat obesity and negative health outcomes associated with it. OBJECTIVES: This systematic review aims to distinguish the impact of a Western diet on gut health verses a plant-based diet. DATA SOURCES: EBSCOHost library databases inclusive of CINAHL plus, ScienceDirect, and PubMed using keywords to better understand the correlation of dietary practices and microbiome balance. STUDY ELIGIBILITY: Criteria that include diet, current research, and scholarly peer reviewed articles. PARTICIPANTS: Ranged from mice to children and adults. INTERVENTIONS: Trends in intervention practices were inclusive of plant-based diets, probiotic use with complimentary prebiotic intake. Research trends away from the Western diet and leans more toward the Mediterranean diet that is high fiber to encourage a diverse microbiome. STUDY APPRAISAL AND SYNTHESIS METHODS: Studies were selectively compared based on diet type and outcome measures. RESULTS: The 39 articles relevant to diet intervention studies on microbiome show decreased risk for obesity when not Westernized. LIMITATIONS: Studies are currently conducted on mice and in small populations. Most of studies were based in the U.S., so a weak international connection was noted. CONCLUSIONS AND IMPLICATIONS: Understanding disease processes associated with variations in microbiome can help researchers target interventions to maintain positive health status. Future research inclusive of diet practices will be valuable in understanding how to improve microbiome to maintain health