Intestinal absorption by Sarotherodon galilaeus (syn Tilapia galilaea ) of Lake Kainji, Nigeria

Carbohydrates, protein, lipid and crude fibre were found to reduce in amount from the anterior to posterior regions along the gut of Sarotherodon galilaeus collected from Lake Kainji. Different regions of the gut exhibited different absorptive powers and all the compounds were differently absorbed in amount. Different sizes of fish showed different absorptive capacit

Possible inclusion of fish waste (scales and fins) in the diet of fishes in aquaculture

The scales and fins of some freshwater fish species (Sarotherodon galilaeus, Oreochromis niloticus, Tilapia zillii, Barbus callipterus, Hemichromis fasciatus) from Kainji Lake, Nigeria were analyzed for their organic and inorganic matter. The aim of such study is to determine the usefulness of these waste parts of the fish in fish feed preparation. In all instances, the inorganic matter was found to be quite high in the fish exoskeleton, and calcium formed the highest element in the scales and the fins. These waste materials are therefore, considered as possible replacement for mineral sources in fish feed and probably the feed for other livestoc

The service contract in Russia: parties, definitions, contents and form

The author provides commentary on the legal regulation of service contracts, and suggests some possible improvements. An article by Mrs E.A. Ershova (Head of the Labour Law Department, Russian Academy of Justice; Candidate of Law, Assistant Professor) published in Amicus Curiae – Journal of the Society for Advanced Legal Studies at the Institute of Advanced Legal Studies. The Journal is produced by SALS at the IALS (Institute of Advanced Legal Studies, School of Advanced Study, University of London)

Sustainable management of water bodies for small-scale fisheries resorces research and development

Abstract The rapid growth of both formal and informal high density urban settlements around major water resources has led to increased pollution of streams, rivers, lakes and estuaries, due to contaminated runoff from these developments. The paper identified major contaminants to be : organic waste (sewage), industrial effluent, pesticides and litter. Pollutant loads vary depending on the hydrology of the urban area, local topography and soil conditions. In some instances, severe pollution of neighbouring and downstream water courses has been observed. The management of catchment land uses, riparian zones, in stream habitat, as well as in stream water flow patterns and quality are necessary in order to sustain the integrity and "health" of water resources, for fisheries and other developments. As such, attempts to ensure a certain level of water quality without attention to other aspects will not automatically ensure a "healthy" ecosystem even as fish habitat. Proper management leads to better water quality and conducive environment for increased fish productio

Stellar Oscillons

We study the weakly nonlinear evolution of acoustic instability of a plane- parallel polytrope with thermal dissipation in the form of Newton's law of cooling. The most unstable horizontal wavenumbers form a band around zero and this permits the development of a nonlinear pattern theory leading to a complex Ginzburg-Landau equation (CGLE). Numerical solutions for a subcritical, quintic CGLE produce vertically oscillating, localized structures that resemble the oscillons observed in recent experiments of vibrated granular material.Comment: 12 Latex pages using aasms4.sty, 2 postscript figures, submitted to the proceedings of the Florida Workshop in Nonlinear Astrophysics and Physic

Comparison of some chemical and non-chemical treatments to disinfect a recirculating nutrient solution

Closed hydroponic growing systems have a better water use efficiency (WUE) and a lower use of fertilizers, but a larger risk of spreading soil-borne pathogens all over the crop compared to open systems. In climates or regions where availability of water is limited closed systems should be preferred above open systems but the risk of spreading soil-borne pathogens should be minimized. Disinfection of the nutrient solution is a valuable method, but it often demands high investments. A desk study was made to compare the performance of some chemical and non-chemical treatments. For larger companies (>2 ha) heat treatment and UV radiation are still the best options. For smaller companies

Recoil proton distribution in high energy photoproduction processes

For high energy linearly polarized photon--proton scattering we have calculated the azimuthal and polar angle distributions in inclusive on recoil proton experimental setup. We have taken into account the production of lepton and pseudoscalar meson charged pairs. The typical values of cross sections are of order of hundreds of picobarn. The size of polarization effects are of order of several percents. The results are generalized for the case of electroproduction processes on the proton at rest and for high energy proton production process on resting proton.Comment: LaTeX2e, 4 pages, 3 figure

On associated polynomials and decay rates for birth-death processes

We consider sequences of orthogonal polynomials and pursue the question of how (partial) knowledge of the orthogonalizing measure for the {\it associated polynomials} can lead to information about the orthogonalizing measure for the original polynomials. In particular, we relate the supports of the two measures, and their moments. As an application we analyse the relation between two decay rates connected with a birth-death process. \u

Associated polynomials and birth-death processes

We consider sequences of orthogonal polynomials with positive zeros, and pursue the question of how (partial) knowledge of the orthogonalizing measure for the {\it associated polynomials} can lead to information about the orthogonalizing measure for the original polynomials, with a view to applications in the setting of birth-death processes. In particular, we relate the supports of the two measures, and their moments of positive and negative orders. Our results indicate how the prevalence of recurrence or $\alpha$-recurrence in a birth-death process can be recognized from certain properties of an associated measure. \u

A comparison of the Si/Al and Si/time wet-alkaline digestion methods for measurement of biogenic silica in lake sediments

Existing techniques for measuring sediment Biogenic Silica (BSi) concentrations rely largely on conventional (Si-only) wet-alkaline digestion methods. Although results have provided detailed palaeoenvironmental information, potential errors can arise in accounting for sources of non-BSi. Here, I compare a conventional Si-only method to a Si/Al wet-alkaline digestion method, which in theory provides a more robust correction for concentrations of non-BSi. Late glacial/Holocene-aged sediment from Lake Baikal, Russia was used for the comparison. Results showed no significant difference between the two techniques, indicating that existing Si-only BSi methods are suitable for reconstructing environmental changes when levels of digested non-BSi are low to moderate