Application of magnetic methods for assessment of soil restoration in the vicinity of metallurgical copper-processing plant in Bulgaria.

Copper ore mining and processing are among the most harmful anthropogenic influences for the environment and they are a subject of international and national law regulations. Recultivation of areas influenced by mining and processing industry is commonly applied and monitored in order to restore as much as possible the natural environment. In this study, environmental magnetic methods are applied in order to assess the degree of soil restoration in terms of soil development, after remediation of waste dump from Cu-processing plant. Soils developed under birch forest stands of different age (5, 15, and 25 years) as well as raw waste material were sampled along depth down to 20-30 cm. Variations in magnetic parameters and ratios obtained (magnetic susceptibility, frequency-dependent magnetic susceptibility, anhysteretic remanence (ARM), isothermal remanence (IRM), ARM/IRM100mT) suggest the presence of magnetic enhancement in the upper 0-15 cm, the thickness of this layer varying depending on the age of the forest stand. Magnetic mineral responsible for this enhancement is of magnetite type, while waste material contains a large amount of hematite, as evidenced by coercivity analysis of IRM acquisition curves and thermal demagnetization of composite IRM. Magnetic grain-sized proxy parameters suggest that magnetite particles are coarser, magnetically stable, while no or minor amount of superparamagnetic grains were detected at room temperature. A well-defined linear regression between the topsoil magnetic susceptibility and the approximate age of the forest stand provides an indication that the magnetic enhancement is of pedogenic origin. It is concluded that the observed magnetic enhancement of recultivated soils studied is linked to a combined effect of pedogenic contribution and possible additions of industrial ashes as a liming agent for soil restoration.

On Methods for the Analysis of Indefinite Stimuli Perception Characteristics: an fMRT Study of Gender-Specific Differences.

Comparative identification of cerebral regions activated in men and women during perception of indefinite images was carried out by fMRT and psychological testing. Nine men and nine women aged 20-26 years took part in the study. The volunteers examined simple geometric figures, slightly structurized images (tables from Rorschach's test), and images of impossible figures. Activation in the cerebellum and visual cortex (bilateral) was more pronounced in women in response to all types of images and less so in the right G. temporalis medius. The right frontal regions (G. precentralis, G. frontalis superior, G. frontalis medius) were also stronger activated in women in response to indefinite stimuli.

A new tool for in situ measurements of the vertical distribution of magnetic susceptibility in soils as basis for mapping deposited dust.

In situ measurements of magnetic susceptibility of topsoils are commonly used for mapping the spatial distribution of atmospherically deposited ferrimagnetic particles. However, the surface measurements integrate signal from certain soil volume and, thus, it is not evident how deep is the magnetically enhanced layer, if there is such. This information is often required for detailed sampling. Furthermore, fast estimate of the significance of lithogenic contribution is needed for the proper interpretation of the surface data. This can be reliably done on the basis of vertical distribution of magnetic susceptibility of a soil column. Until now, there was practically no reliable, fast and sensitive enough tool to carry out these measurements in real time, directly in field. In this paper, we report on a new soil-profile kappameter SM400, which enables continuous real-time measurements, performed directly in the field. We describe its basic measurement principles. Performance parameters are discussed, showing that sensitivity is high enough to depict the soil layers with different susceptibility and a data density of 6 points per 1 mm of depth, which results in smooth curves of susceptibility, unlike field or laboratory probes used until now. Profiles acquired using different probes and instruments are compared in order to demonstrate advantages of the new approach.

Cholesterol content in market hen eggs.

The yolk cholesterol content in eggs of White Hisex laying hybrid from 3 specialized commercial farms averaged 1230, 1330 and 1230 mg/100 g of yolk over an 11-months laying period, i.e. 303, 304 and 309 mg cholesterol/100 g of consumable egg portions. In testing Babcock B-380, Moravia SSL, Shaver Starcross 288, and Hisex HX-1, the av. cholesterol content varied from 1200 to 1360 mg/100 g of yolk or from 372 to 444 mg/100 g of consumable egg portions. Throughout the egg-laying period, the yolk cholesterol content fluctuated rather irregularly and showed great variability (variation coefficient 9.7-18.2%). The values recorded failed to follow any of the common functions of the trend. Intensive market egg production was found to be associated with decreases in yolk cholesterol content.

Effects of ethylnitrosourea on the hatchability and survival of chicks.

1. Two experiments were carried out to study the effects of the mutagen ethylnitrosourea (ENU) at concentrations of 1.4 to 3 500 microgram in 0.3 ml of saline (experiment 1) and 585 to 1 170 microgram in 0.1 ml of saline (experiment 2) on hatching eggs of two breeds of fowls. Hatchability (experiment 1) and survival up to 7 d of age without food (experiment 2) were assessed. In experiment 1 the hens were fed on different diets prior to providing the hatching eggs. 2. The mutagen showed a non-linear effect upon the hatchability, higher doses being less effective than small doses. 3. In the majority of cases, female embryos were more sensitive to the effect of ENU then male. 4. The mortality after hatching was also affected by ENU; the chicks from treated eggs surviving without food better then controls.

[Induction of components of the natural precipitation system (GANS) and another antibody after alloimmunization with serum or egg yolk in fowl]. / Indukce slozek prirozeného precipitacního systému (GANS) a dalsí protilátky po aloimunizaci sérem nebo vajecným zloutkem u kura.

Detailed analysis was performed in 17 selected serums obtained through alloimmunization of 64 receptors (cocks and hens, WP X RIR hybrids) of type 0 in the GANS system. The serum or egg yolk from hens of type A or B in the GANS system, used for immunization, was applied in five intramuscular injections with or without using Freund's complete adjuvant. It was found out that substance A GANS was present in 16 serums of the total number of those which were examined, so that in the receptors the application of serum or yolk changed the type of the GANS system from original 0 into type A, irrespective of the type of donor. Further, seven serums were found to contain another antibody, reacting in precipitation with the serum fraction which is only present in laying hens and probably has not the character of an allotype.