Novel Edge States in Self-Dual Gravity

In contrast to the Einstein-Hilbert action, the action for self-dual gravity contains vierbeins. They are eleminated at the level of observables by an $SL(2,\mathbb{C})$ gauge condition implied by the action. We argue that despite this condition, new "edge" or superselected state vectors corresponding to maps of the spheres $S^2_{\infty}$ at infinity to $SL(2, \mathbb{C})$ arise. They are characterised by new quantum numbers and they lead to mixed states. For black holes, they arise both at the horizon and the spatial infinity and may be relevant for the black hole information paradox. Similar comments can be made about the Einstein-Palatini action which uses vierbeins.Comment: 15 pages, reference added, some minor notational changes - no changes in conclusio

Anomalous Defects and Their Quantized Transverse Conductivities

Using a description of defects in solids in terms of three-dimensional gravity, we study the propagation of electrons in the background of disclinations and screw dislocations. We study the situations where there are bound states that are effectively localized on the defect and hence can be described in terms of an effective 1+1 dimensional field theory for the low energy excitations. In the case of screw dislocations, we find that these excitations are chiral and can be described by an effective field theory of chiral fermions. Fermions of both chirality occur even for a given direction of the magnetic field. The ``net'' chirality of the system however is not always the same for a given direction of the magnetic field, but changes from one sign of the chirality through zero to the other sign as the Fermi momentum or the magnitude of the magnetic flux is varied. On coupling to an external electromagnetic field, the latter becomes anomalous, and predicts novel conduction properties for these materials.Comment: New material added. ReVTeX , 31 pgs., 4 figs.(uses epsf

Determination of the best feeding ratio in Huso huso meat production cultured in fiber glass tanks

A two-phase random growth test was conducted to evaluate the effects of feeding rate on growth performance, food conversion ratio (FCR), specific growth rate (SGR), feeding efficiency and price index of reared Huso huso fingerlings in fiberglass tanks (2x2x0.53 cm). Rearing conditions such as diet, dissolved oxygen, light, water flow, fish density and feeding frequency were kept similar for the tanks. In the first phase, 180 fingerlings with a mean weight 867.86±17.42g were fed for 100 days in four treatments and three replications at feeding rates 1, 2, 3 and 4 percent of their biomass. In the second phase, also four treatments and three replications were applied to 84 Huso huso with a mean weight 2096.1±35.6g. In this phase, the fish were fed for 125 days with 0.75, I .5, 2.5 and 3 percent of their biomass. During rearing period, water temperature was 25.52±1.78 and 14.82±0.48 degrees centigrade and dissolved oxygen was 7.6±0.3 and 7.89±0.18 mg/lit, for the two phases respectively. The fishes were fed four times daily with a diet containing 40% protein, 13% fat and 9.9% ash. All treatments induced fast growth in the fish, but feeding ratios were different in their effects on the growth (P<0.05). Weight gain percentage, specific growth rate (SGR), food conversion ratio (FCR), feeding efficiency and price index indicated that lower feeding ratios were more effective in causing fish growth (P<0.05). So, increase in feeding ratio directly increased daily food consumption (D.F.C) and negatively affected the feeding efficiency, food conversion ratio, specific growth rate and price index (P<0.05). The results showed that in phase one, when the fish were given food as much as two percent of their body weight, one unit of meat was produced by consuming 1.92 units of food. In the second phase, feeding fish with 0.75 percent of their body weight resulted in producing one unit of fish meat per 1.82 units of food consumed. Also, in the two phases, application of higher than 50% feeding ratio increased costs while no significant trend in fish growth was detected. It can be concluded that regarding the water temperature, the optimal feeding rate for fishes weighing 850 to 1900 grams and those weighing 2050 to 3300 grams are 2 % and 1 % of body weight, respectively

Supply response of potato in Bangladesh: a vector correction approach

An attempt has been made in this study to examine the supply response of potato in Bangladesh by using the vector error correction approach. The short-run price elasticity was 0.45 while the long run elasticity was 0.62. Price policies are effective in obtaining the desired level of output for potato. If intervention in the market is of necessity, then it must be implemented during the harvest season for altering price expectations. Also emphases should be given to increase potato export and establishing export oriented potato processing industries

Monitoring teških metala (Cu, Pb, Cd, Zn) u vodama Shahid Beheshti mrestilišta jesetri, Rasht, Iran

The presence of heavy metals; copper (Cu), lead (Pb), cadmium (Cd) and zinc (Zn) in water was monitored during different stages of breeding and rearing of Acipenser persicus at the Shahid Beheshti Sturgeon Hatchery. Water samples were collected (3 samples from each point) from the main pond, Kurenski pond, incubators, vniro tanks, earthen ponds and at the river estuary where fingerlings are released into the sea. Water parameters such as pH and water and air temperature were measured and recorded at the time of sampling. Heavy metal concentrations in water samples were determined using Atomic Absorption Spectrophotometer FAAS-Varian AA-220. In the present study the distribution pattern for heavy metal concentrations in different stages of breeding and rearing was as follows: Zn>Cu>Pb>Cd. Highest concentrations of heavy metals belonged to the element Zn (36.0±3.6 ppb) which was determined in the water sample collected from the inlet of master pond. Lowest concentration for Zn recorded was 0.98±0.26 ppb. Highest concentration for Cu was 10.5±1.18 ppb and the lowest concentration for this element was 0.65±0.26 ppb. The highest and lowest concentrations recorded for lead were 9.33±1.19 and 0.15 ±0.01 ppb, respectively, while those for cadmium were 0.116±0.019 and 0.016±0.003 ppb, respectively. The results obtained indicate the presence heavy metals studied in the water samples although they were lower than the maximum permissible concentration for these pollutants for the breeding and rearing of Acipenser persicus in sturgeon hatcheries

On Weighted Nwikpe Distribution: Properties and Applications

In this article, two-parameter continuous distribution is introduced. The proposed distribution is obtained by using a weight technique and is referred to as weighted Nwikpe distribution. This distribution is a generalization of baseline distribution that is Nwikpe distribution. Some structural properties of the distribution are derived. These are density function, distribution function, and reliability function, hazard rate function, moments, moment generating function, entropies, order statistics, Bonferroni and Lorenz curves. The method of maximum likelihood estimation has been established for investigating the parameters of the model. The behaviour of the parameters of the distribution is examined by a simulation study. Real data set is used to determine whether the weighted Nwikpe distribution is better than other well-known distributions in modeling data or not