Measurement of species flux from a bubble using an acousto-electrochemical technique

An acousto-electrochemical technique is presented which, for the first time, offers the potential for measuring the flux of dissolved species in a liquid resulting from bubbles of a specific chosen size in the population. Laboratory trials are presented, but the device itself was damaged in the surf zone and no data was obtained from the ocean deployment. Nevertheless, the preceding laboratory tests demonstrate the viability of the technique. The device responds to perturbations of the fluid around a small electrode. Three such sources of motion must be characterised if it is to achieve the objective stated above. First, the perturbations resulting form the translatory motions of bubbles in the liquid. To obtain bubble radius resolution in the measurement of mass flux, however, it is necessary to apply to driving (‘pump’) sound field. Bubbles close to resonance will, in addition to a translatory motion, impart to the liquid a component of mass flux at the pump frequency. This is detected. However to show that this is the result of bubble wall pulsation, and not someother coupling, the amplitude of the pump field is increased until the electrochemical sensor detects Faraday waves on the bubble wall. Not only does this prove the relation between mass flux to bubble wall motion, it provides a second route by which the radius-resolved component of mass flux might be identified. In these preliminary laboratory tests, electrochemical detection of these motions was achieved through the observation of current produced by the reduction of a suitable redox agent present within the liquid phase of the solution employed. Preparations were made to obtain preliminary data from the Hurst Spit 2000 surf zone trial, but the device was damaged by the environment

Galaxy Zoo Builder: Four-component Photometric Decomposition of Spiral Galaxies Guided by Citizen Science

Multicomponent modeling of galaxies is a valuable tool in the effort to quantitatively understand galaxy evolution, yet the use of the technique is plagued by issues of convergence, model selection, and parameter degeneracies. These issues limit its application over large samples to the simplest models, with complex models being applied only to very small samples. We attempt to resolve this dilemma of "quantity or quality"by developing a novel framework, built inside the Zooniverse citizen-science platform, to enable the crowdsourcing of model creation for Sloan Digital Sky Survey galaxies. We have applied the method, including a final algorithmic optimization step, on a test sample of 198 galaxies, and examine the robustness of this new method. We also compare it to automated fitting pipelines, demonstrating that it is possible to consistently recover accurate models that either show good agreement with, or improve on, prior work. We conclude that citizen science is a promising technique for modeling images of complex galaxies, and release our catalog of models

Anthocyanins, phenols, and antioxidant activity in blackberry juice with plant extracts addition during heating

In this work the influence of addition of different plant extracts (olive leaf, green tea, pine bark PE 95%, pine bark PE 5:1, red wine PE 30%, red wine PE 4:1, and bioflavonoids) to blackberry juice during heating (at 30, 50, 70 and 90 °C) on the anthocyanin and phenol contents, polymeric colour, and antioxidant activity was investigated. Also, reaction rate constant, half-lives of degradation, and activation energy were calculated. Control sample was juice without addition of extracts. The highest anthocyanin content at 30 °C was in samples with the addition of olive leaf and green tea. At 90 °C the highest anthocyanin content was measured in samples with the addition of extract of red wine and bioflavonoides. Samples supplemented with the extracts had much higher antioxidant activity in comparison to the control sample. Results showed that at 90 °C the sample with green tea supplementation had the lowest reaction rate constant and the highest half-life. Activation energy ranged from 29 to 44 kJ mol−1

The Mathematical Universe

I explore physics implications of the External Reality Hypothesis (ERH) that there exists an external physical reality completely independent of us humans. I argue that with a sufficiently broad definition of mathematics, it implies the Mathematical Universe Hypothesis (MUH) that our physical world is an abstract mathematical structure. I discuss various implications of the ERH and MUH, ranging from standard physics topics like symmetries, irreducible representations, units, free parameters, randomness and initial conditions to broader issues like consciousness, parallel universes and Godel incompleteness. I hypothesize that only computable and decidable (in Godel's sense) structures exist, which alleviates the cosmological measure problem and help explain why our physical laws appear so simple. I also comment on the intimate relation between mathematical structures, computations, simulations and physical systems.Comment: Replaced to match accepted Found. Phys. version, 31 pages, 5 figs; more details at http://space.mit.edu/home/tegmark/toe.htm

A Study of Astaxanthin : Its Application for the Pigmentation of Salmonid Fish

1. The pink-red coloration of the flesh of salmonids is due to carotenoids, especially astaxanthin, and is an important factor to evaluate marketing value of cultured salmonids. For many years fish technologists and scientists have endeavored to enhance the coloration of salmonids through the use of crustacean waste, yeast, algae, flower patels and synthetic carotenoids. 2. Synthetic canthaxanthin and astaxanthin are the two most effecient carotenoids for pigmenting salmonids, and are now widly used in salmonids culture. 3. The metabolism of astaxanthin in salmonids has been studied. The reductive metabolism of astaxanthin to β-carotene have been proposed. The proposed pathways are ; Astaxanthin→idoxanthin→adonixanthin→zeaxanthin, and Canthaxanthin→4-hydroxyechinenone→echinenone→β-carotene. 4. One of well-known functions of carotenoids in fish is pro-vitamin A activity. Salmonid fish are able to convert β-carotene, canthaxanthin, lutein, zeaxanthin and astaxanthin, into vitamin A

The global atmospheric electrical circuit and climate

Evidence is emerging for physical links among clouds, global temperatures, the global atmospheric electrical circuit and cosmic ray ionisation. The global circuit extends throughout the atmosphere from the planetary surface to the lower layers of the ionosphere. Cosmic rays are the principal source of atmospheric ions away from the continental boundary layer: the ions formed permit a vertical conduction current to flow in the fair weather part of the global circuit. Through the (inverse) solar modulation of cosmic rays, the resulting columnar ionisation changes may allow the global circuit to convey a solar influence to meteorological phenomena of the lower atmosphere. Electrical effects on non-thunderstorm clouds have been proposed to occur via the ion-assisted formation of ultra-fine aerosol, which can grow to sizes able to act as cloud condensation nuclei, or through the increased ice nucleation capability of charged aerosols. Even small atmospheric electrical modulations on the aerosol size distribution can affect cloud properties and modify the radiative balance of the atmosphere, through changes communicated globally by the atmospheric electrical circuit. Despite a long history of work in related areas of geophysics, the direct and inverse relationships between the global circuit and global climate remain largely quantitatively unexplored. From reviewing atmospheric electrical measurements made over two centuries and possible paleoclimate proxies, global atmospheric electrical circuit variability should be expected on many timescale