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—The electronic spectra of Ni II as the promoter of a hydrodesulfurization catalyst (NiO-MoO 3 /γ-Al 2 O 3 ) has been studied. On the basis of the positions and intensities of the maxima in electronic d-d transitions the presence of an octahedral point group symmetry (O h ) of Ni II was established for the untreated sample and samples taken from the regenerated catalyst layers. In other cases, the distribution of d-d transition maxima indicated that in addition to the octahedral (O h ) a tetrahedral (T d ) coordination of Ni II was also present, suggesting the occurrence of a spinel-type structure. The experimental values obtained for the crystal field splitting parameter (10D q ) enabled calculation of the electronic state energies, as well as the values of parameters of partially populated d-orbitals of Ni II . On the basis of these data, the effective values of ionization potential H dd were calculated and a most probable MO scheme was proposed.

Possibility to chemically control weeds in spring rapeseed has been tested in two locations ( Novi Sad and Kragujevac) and following herbicides (a.i.) : trifluralin, clomazone, quizalofop-p-ethyl and clopyralid. We tested the effect of the herbicides on yield and hectoliter weight of seed and oil and protein contents in seed. In the trial in Kragujevac, a large number of weed species were present, with somewhat increased density and uneven distribution of weed plants. This was particularly evident with grassy weeds and with the species Rubus caesius in several plots. Rapeseed yield and quality were determined by measuring and analyzing the following parameters: grain yield (kg/plot (30 m2), hectoliter weight, oil content (%) and protein content (%) in seed.Basic statistical calculations of rapessed yield and quality were done by the t-test. The tested herbicides showed no adverse effect on the yield and hectoliter weight of seed in either location, with the exception of quizalofop-p-ethyl in Kragujevac, which affected the control variants. Oil content was negatively affected by the combination, trifluralin + clopyralid in the location of Novi Sad and by quizalofop-p-ethyl in the other location. Trifluralin and quizalofop-p-ethyl exhibited a negative effect on protein content in the location of Novi Sad, while there were no statistically significant negative effects in the other location.

Mutual relationships have been studied between seven plant end seed characteristics (plant height, number of leaves per plant, 1000-seed mass, hectoliter mass, kernel content, seed thickness, seed width) and their correlation with oil content in seed. Significant of highly significant correlations have been found between oil content on one side and 1000-seed mass, hectoliter mass, kernel content, and seed thickness on the other. Anon-significant negative correlation was registered for the number of leaves per plant, non-significant positive correlations for plant height and seed width. The path analysis has revealed a highly significant positive direct effect of hectoliter mass and kernel content and a significant negative direct effect of seed width on oil content in seed. The coefficient of determination has shown that 79.5% of the total variability for oil content were controlled by the factors studied.

Intensive sintering processes and disturbances of microstructure of NiO-MoO3/γ-Al2O3 and CoO-MoO3/γ-Al2O3 hydrodesulfurization catalyst systems have been established as one of the main causes of catalyst deactivation. Segregation of MoO3 from the complex active structure during processing, with consecutive melting in regeneration cycle, has been proposed as the main reason of intensive sintering of the catalyst. That leads to essential change in porous structure depending on regeneration atmosphere in order: nitrogen-air-steam.

This paper presents results of new investigations on morphology and motor function of basal ganglia, which point to the fact that their dimensions are individual and not correlated with the dimension of the corresponding hemisphere. Basal ganglia motor function is studied on the basis of disturbances which occur if they are damaged, both in sick people and experimental animals. Analysis of recorded single-neuron activity, in animals and in patients undergoing special surgical procedures, is especially instructive for understanding this function. According to new insights there are at least five multiple neuronal regions: motor, oculomotor, limbic, dorsolateral prefrontal and lateral orbitofrontal region. Morphologic and functional studies partly disagree in interpreting connections among these regions. On the basis of functional studies it is considered that parallelism and functional separation exist, while on the basis of morphologic studies it is considered that at the level of basal ganglia output convergence occurs. New insights speak about parallelism and convergence at the same time. It is thought that inside basal ganglia motor region there are two divided systems, direct and indirect, which direct the output impulses towards talamus. The direct leads to facilitation of cortically started movements, and the indirect to suppression of unwanted motor behavior. On the basis of literature data we can conclude that basal ganglia support cortically generated movements, participate in sequential movements, suppress unwanted motor activity and in altered circumstances stop the course of started motor sequences allowing new, adequate motor activity.

Vascular network of gyrus cinguli has been examined in adult brains. This vascular network is extended in the form of a cone from lower to upper lip of Sulcus corporis calosi. The blood vessels in the area of lower lip and bottom of the Sulcus corporis calosi are oriented obliquely, almost parallel to cerebral cortex surface, while in the area of upper lip of sulcus are oriented perpendicularly to the cerebral cortex surface. Arteries in this area have few recurrent branches, while fountain shaped arteries are found infrequently. Shorter spiral arteries are found, too. Longer veins predominates in this area (V4 and V5). Drainage territories of certain veins are larger than irrigation territories of the appropriate arteries.

The vascular network of the area striata consists of four vascular layers. The capillary network of the first vascular layer is completely filled only in some parts of the area striata. The capillary networks of second, third and fourth vascular layer have high density, although the capillary networks in border zones of each two adjacent cortical arteries have lower density. In the area striata the fountain-like arteries have been found, with some collateral branches dividing in fountain-like branches, too. In the brain of a 70 year old male we have found collateral branches initially twisted around its main trunk. The tangential sections of the area striata show the existence of vertically-oriented vascular units with centrally located venous vessel surrounded with one or two arterial rings.

The vascular network of the anterior part of the middle and inferior temporal gyri consists of four vascular layers of which the third and fourth have the densest capillary network of the same density. There are all types of arteries in this cortex form A1 to A6 as well as all types of veins from V1 to V5. Fountain-like arteries usually branch into five to six terminal recurrent branches; we have found that there are about two of them in each serial section. The middle temporal visual area has the same features of the vascular network as the above mentioned gyri with one difference only: there are at least six fountain-like arteries in each serial section. The increased number of these arteries might point to a greater sensitivity of this area to hypoxic conditions. The tangential sections of these areas reveal the existence of vertically-oriented vascular units with a centrally located venous vessel surrounded by arterial rings.

The investigation of the morphological features of vascular network of superior temporal gyrus was carried out on eight hemispheres of brains of adults from 36 to 48 years old died in accidents without visible signs of central nervous system diseases. Vascular network of auditory areas is characterised by very dense capillary network of the third vascular layer which is the densest one in these areas. The vascular network of the anterior part of the superior temporal gyrus is distinguished by equal density of the third and fourth vascular layer. Fountain-like arteries are mostly of type A3 and A4 and have been found in all parts of the superior temporal gyrus. Vertical functional units of the cortex are supplied by a number of precapillary arterioles being arranged in the shape of a ring. In the center of each unit there is postcapillary venule through which it is drained.

The morphology and the left-right asymmetry of the frontal lobe convexity (sulcus frontalis superior and inferior, sulcus precentralis, gyrus precentralis, gyrus frontalis superior and medius) were studied on 19 formaline fixed human brains. During the study, the gyral and sulcal patterns were marked as similar, partially similar or different. Sulcal patterns on the left and right side were completely different (in at least more than half) in the greatest number of cases. Gyral patterns were also asymmetric (mirror image analysis). However, using the "essential gyral line"--the line indicating longitudinal gyral axis--the results changed dramatically. The majority of patterns appeared to be very similar, indicating that the method of analysis largely influences the results of morphological studies of human brain asymmetry. This explains different findings reported in the literature. We suggest that the use of the "essential gyral line" provides standardized method of morphological analysis, which was not available up to date.

The arterial supply of the amygdaloid body was studied on 20 brains of adult individuals of both sexes. The middle cerebral and anterior choroidal artery were selectively injected with a mixture of India ink and 5% gelatin solution. By injecting the middle cerebral artery, we filled the blood vessels of the putamen, the lateral part of globus pallidus, the internal capsule, claustrum, insular cortex and the cortex of the convex side of the hemisphere, whereas the blood vessels of the amygdaloid body remained unfilled by the mixture. By injecting the anterior choroidal artery, the blood vessels of the medial part of globus pallidus and of the amygdaloid body were filled, except in one case, when the blood vessels were filled only in it's posterior part. Based on the results obtained, a conclusion may be drawn that the branches of the anterior choroidal artery play the main role in the amygdaloid body arterial supply.

Microvascularization of the brain cortex was investigated in 21 brains of human fetuses, from 15th to 25th postovulatory week and one adult human brain. Blood vessels injected with ink-gelatine solution were examined on preparations lighted by the Spalteholz method. In all examined stages of fetal development as well as in the adult brain a regular geometric arrangement of the blood vessels which radially penetrated the brain substance was observed. Centrally placed vascular trunk of bigger diameter surrounded by the blood vessels of smaller calibre was registered. On the basis of the obtained results it can be concluded that the vascularization of the brain cortex in all examined stages of the development follows the pattern of radially placed vascular units.

A study of the volume density of the ganglionic eminence vascular network and the constituent parts of the corpus striatum was performed on 8 chosen foetal brains, which were well-injected with a mixture of India ink and gelatin, aged from 14-25 postovulatory weeks. The volume density of the ganglionic eminence vascular network amounts to 0.0209-0.0300 mm0, of the caudate nucleus to 0.0131-0.0181 mm0, of the putamen to 0.0136-0.0159 mm0, and of the globus pallidus to 0.0121-0.0159 mm0. The comparison of the results obtained, shows that the volume density of the ganglionic eminence vascular network is higher than the volume density of the other examined structures and that this difference is statistically highly significant (p less than 0.01). The augmented volume density of the ganglionic eminence vascular network points to a possibility of slow blood flow through its vascular bed, which was experimentally demonstrated on animals. This slow blood flow, among other factors, may be the cause of a ganglionic eminence venous infarction in premature newborns of low birthweight.

The blood vessels of the insular cortex and the claustrum were studied in 26 foetal brains of 16--25-week-old foetuses and one adult brain without noticeable pathological signs. The labelling of the vessels was wade according to Duvernoy et al. (1981). In 16-week-old foetuses arteries of types A6 as the A5 were found in the insular cortex as well as the veins of type V5. In 19-week-old foetuses the arteries of type A4 and the veins of type V4 appeared as only cortical vessels. In the following stages of the brain development the shorter and shorter arteries appeared so that in 24-week-old foetuses one could see all the types of arteries from A6 to A1. However, in the period from 19 to 25 weeks, no vein shorter than that of the type V4 was found in the insular cortex. In the adult brain it was possible to identify all the types of arteries and veins in the insular cortex, but distances between the individual vessels were larger in comparison with those in the insular cortex of the foetal brains. There claustrum was vascularized by the arterial branches from the insular arteries, whereas in the adult brain the claustrum received some of the branches from the striate arteries as well. This pattern of the vascular supply may indicate the common origin of the claustrum and the insular cortex.

The claustrum is vascularized by 3 groups of arteries which come out of the middle cerebral artery. The first group of arteries reaches the claustrum through the limen of insula and vascularizes the anterior and ventral part of the claustrum, mostly. The second group of arteries reaches the claustrum through the cortex of insula, and vascularizes the dorsal part of the claustrum, mostly. The third group of arteries comes out of the lateral striated arteries and occasionally vascularizes the claustrum, only in the adult age. On the basis of our research, we think that the primary claustral arteries are the ones which reach the claustrum through the limen and cortex of insula and they take the lead in the vascularization of the claustrum. The arteries which come out of the lateral striated arteries, we consider as secondary claustral arteries, and their role in claustral vascularization is occasional and of small importance.

The development of the dentate nucleus was studied on 12 brains of the human fetuses of different crown-rump length (CRL) and one newborn. The first appearance of the dentate nucleus was noticed in the fetus 12.5 weeks old. The dorsomedial lamina begins to grow in the 13th week and to fold in the 20th week. The ventrolateral lamina begins to grow in the 20th week and to fold in the 23.5th week. During the development of the dentate nucleus, 2 important periods can be determined. The first period corresponds to the first appearance of the dentate nucleus (12.5 weeks) and the second period corresponds to intensive growth of the dorsomedial and ventrolateral lamina (20-24.5 weeks).

The density of the myocardiac vascular network in 3-month-old female Wistar rats exposed to intermittent hypoxia was studied. The experimental rats were sacrificed immediately (1st experimental subgroup) or 4 days (2nd experimental subgroup) after the last exposition. The volume density was statistically highly significant in the animals of the 1st subgroup and significant in the rats of the 2nd subgroup. The highly significant rise in the volume density of the myocardiac vascular network could be explained by an acute stress effect, whereas the only significant increase in the second case indicates adaptability to stress.

The development of the blood network of the dentate nucleus was studied on 20 human fetal brains of different crown-rump length (CRL). In the stage of 17 to 20 weeks, the blood network of the dentate nucleus consisted of moderate spiral blood vessels. They anastomosed each other and made irregular elongated polyhedral meshes. From this meshwork, blood vessels of a greater volume arose and extended to the hilum of the nucleus. Between 23 and 25 weeks, a clear segmental vascular pattern was noticed. The capillary network was very dense. Along the outer surface of the nucleus the blood vessels which connected two secondary wrinkles of the gray matter were observed. In all the stages investigated the blood vessels were moderately spiral.