Abstract. We present the results of a ship survey conducted from Italy to Antarctica and back during the 1996-1997 solar minimum measuring the latitude variation in the neutron component of cosmic radiation at sea level. High-energy atmospheric neutrons were detected by a 3NM-64 and thermalized atmospheric neutrons were detected by two bare BF3 counters. Discussions of the internal consistency of the data and the stability of the detectors, investigations of meteorological effects, and data corrections are presented in two companion papers. In this paper we compute updated vertical cutoff rigidities corrected for the penumbra effect, and we estimate apparent cutoff rigidities, which take into account the contribution of nonvertically incident particles to the counting rate. When comparing cosmic ray intensities observed in the same place, a small forward-backward effect is found and explained as the effect of an asymmetric shielding structure around the monitor. Latitude dependencies (i.e., neutron intensities versus cutoff rigidity) and associated coupling functions are computed for both monitors and compared. The NM latitude dependence obtained for the 1996-1997 solar minimum is found to be almost identical to that obtained by other authors in the previous solar minimum. The absence of the so-called "crossover" effect when comparing coupling functions of subsequent solar minima is discussed also on the basis of cosmic ray intensity changes observed by neutron monitor stations.

The heat shock (HS) response is an adaptation of organisms to elevated temperature. It includes substantial changes in the composition of cellular membranes, proteins and soluble carbohydrates. To protect the cellular macromolecules, thermophilic organisms have evolved mechanisms of persistent thermotolerance. Many of those mechanisms are common for thermotolerance and the HS response. However, it remains unknown whether thermophilic species respond to HS by further elevating concentrations of protective components. We investigated the composition of the soluble cytosol carbohydrates and membrane lipids of the thermophilic fungi Rhizomucor tauricus and Myceliophthora thermophilaat optimum temperature conditions (41-43 С), and under HS (51-53 С). At optimum temperatures, the membrane lipid composition was characterized by a high proportion of phosphatidic acids (PA) (20-35 % of the total), which were the main components of the membrane lipids, together with phosphatidylcholines (PC), phosphatidylethanolamines (PE) and sterols (St). In response to HS, the proportion of PA and St increased, and the amount of PC and PE decreased. No decrease in the degree of fatty acid desaturation in the major phospholipids under HS was detected. The mycelium of all fungi at optimum temperatures contained high levels of trehalose (8-10 %, w/w; 60-95 % of the total carbohydrates), which is a hallmark of thermophilia. In contrast to mesophilic fungi, heat exposure decreased the trehalose level and the fungi did not acquire thermotolerance to lethal HS, indicating that trehalose plays a key role in this process. This pattern of changes appears to be conserved in the studied filamentous thermophilic fungi.

Alkaliphily, the ability of an organism to thrive optimally at high ambient pH, has been well-documented in several lineages: archaea, bacteria and fungi. The molecular mechanics of such adaptation has been extensively addressed in alkaliphilic bacteria and alkalitolerant fungi. In this study, we consider an additional property that may have enabled fungi to prosper at alkaline pH: altered contents of membrane lipids and cytoprotectant molecules. In the alkaliphilic Sodiomyces tronii, we showed that at its optimal growth pH 9.2, the fungus accumulates abundant cytosolic trehalose (4-10% dry weight) and phosphatidic acids in the membrane lipids, properties not normally observed in neutrophilic species. At a very high pH 10.2, the major carbohydrate, glucose, was rapidly substituted by mannitol and arabitol. Conversely, lowering the pH to 5.4-7.0 had major implications both on the content of carbohydrates and membrane lipids. It was shown that trehalose dominated at pH 5.4. Fractions of sphingolipids and sterols of plasma membranes rapidly elevated possibly indicating the formation of membrane structures called rafts. Overall, our results reveals complex dynamics of the contents of membrane lipids and cytoplasmic sugars in alkaliphilic S. tronii, suggesting their adaptive functionality against pH stress.

A portion of the "Gomori-positive" peptidergic neurosecretory (NS) cells in the paraventricular and especially in the supraoptic and postoptic nuclei degenerate three weeks after deafferentation of the medial basal hypothalamus. Most of the remaining NS cells show signs of high activity. Regenerating NS fibres form "muffs" around the blood vessels laterally from the lesion; some of them enter the "isolated" area or persist there if a thin layer of the brain tissue is left somewhere untouched under the basal end of the cut. The regenerating NS fibres are also found outside the nervous tissue: within the scar tissue, in the proliferating connective tissue of the brain sheet below the basal end of the cut and in the mantel plexus area. The NS fibres make close contact with blood vessels invading or penetrating the vascular wall. It is suggested that peptide neurohormones discharged from the "Gomori-positive" NS terminals enter the general blood circulation as well as the portal blood at the site of these newly formed axovasal contacts. It is supposed that under these conditions monoaminergic terminals do not discharge monoamines because no stimulation of monoamine-producing NS cells occurs with deafferentation.

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