Ultrastructural studies of the mitochondriae in the striated muscles of birds with regard to experimental hypokinesis

Electron microscopic studies were carried out on the mitochrondria of the transversely striated muscles with regard to experimental hypokinesia. As compared to the central group the mitochondria of m. pectoralis thoracicus and the m. iliotibialis posterior in hypokinetic birds reveal marked changes. In filamentous and ovoid mitochondria, vacuoles can be observed which in some cases produced larger light formations with following disappearance of the cristae and destruction of mitochondria. Fat particles located at the poles of the altered mitochondria, sporadically occurring also laterally, presented another finding. The Z-lines of the sarcomere did not form a continuous line, but were somewhat shifted

Electron microscopical and histochemical studies on the transverse striated muscles of birds after prolonged hypokinesis

Studies of the gastrocnemius muscle were carried out in 4 month old cockerels of the laying hybrid after hypokinesis lasting 15 and 30 days. It was found that restricted movement resulted in dystrophic changes of myotibrils, enlargement of the sarcoplasmic reticulum and oedem of interfibrillar spaces. Histochemical studies revealed focuses of increased activity of non-specific esterase, decreased activity of dehydrogenase of lactic acid and a positive reaction of acid phosphatase

Discriminant Function Analysis of Miocene Volcaniclastic Rocks from North-Western Croatia Based on Geochemical Data

Preliminary results of discriminant function analysis of geochemical data of Miocene volcanic and volcaniclastic rocks revealed that it is possible to distinguish rocks of different ages, namely Egerian-Eggenburgian, Karpatian and Badenian. On the basis of calculated coefficients of classification functions, presented in the paper, it is possible to indicate the age of Miocene volcanic and volcaniclastic rocks if their trace element content is known. The analysis also showed that, especially in the case of volcaniclastic rocks, the mineral and petrological composition of the rocks should also be considered. Most of the investigated volcaniclastic rocks from the Mozdjenec and Kalnik areas, the age of which was unknown, are, according to discriminant function analysis, of Egerian-Eggenburgian age

Three-dimensional molecular dynamics simulations of void coalescence during dynamic fracture of ductile metals

Void coalescence and interaction in dynamic fracture of ductile metals have been investigated using three-dimensional strain-controlled multi-million atom molecular dynamics simulations of copper. The correlated growth of two voids during the coalescence process leading to fracture is investigated, both in terms of its onset and the ensuing dynamical interactions. Void interactions are quantified through the rate of reduction of the distance between the voids, through the correlated directional growth of the voids, and through correlated shape evolution of the voids. The critical inter-void ligament distance marking the onset of coalescence is shown to be approximately one void radius based on the quantification measurements used, independent of the initial separation distance between the voids and the strain-rate of the expansion of the system. The interaction of the voids is not reflected in the volumetric asymptotic growth rate of the voids, as demonstrated here. Finally, the practice of using a single void and periodic boundary conditions to study coalescence is examined critically and shown to produce results markedly different than the coalescence of a pair of isolated voids.Comment: Accepted for publication in Physical Review

Changements intervenant dans l’ultrastructure de la barrière alvéolo-capillaire lors de l’œdème pulmonaire experimental chez le lapin

Lazarov V., Belak M. Changements intervenant dans l’ultrastructure de la barrière alvéolo-capillaire lors de l’oedème pulmonaire expérimental chez le lapin. In: Bulletin de l'Académie Vétérinaire de France tome 122 n°1, 1969. pp. 59-64

Discovery of Blueschists in the Medvednica Mountain (Northern Croatia) and Their Significance for the Interpretation of the Geotectonic Evolution of the Area

Blueschists were discovered in the metamorphic rocks of the Medvednica mountain. Two varieties of blueschists are recognised, one with garnets and another with omphacite. Determined mineral associations are composed of sodic amphibole (glaucophane and crossite), garnet, omphacite and white mica. These mineral associations indicate metamorphic conditions which are transitional between blueschist and eclogite facies, i.e. high pressures at relatively moderate temperatures (LG, HP/LT). Such conditions are often characteristic of subduction zones. The occurrence of high-pressure metamorphic rocks in the Medvednica mountain, together with local outcrops of ultramafic rocks (serpentinised harzburgite, dunite and serpentinite) indicate subduction related rocks of the Dinaric part of the Tethyan oceanic crust. In the northern part of the Dinarides, ultramafic rocks and glaucophane schists have also been found in the Motajica and Fruska gora mountains. The Medvednica-Motajica-Fruska gora zone probably represents a relict subduction zone in the Dinaridic part of Tethys, along which regional high-pressure metamorphism took place

Effect of stress-triaxiality on void growth in dynamic fracture of metals: a molecular dynamics study

The effect of stress-triaxiality on growth of a void in a three dimensional single-crystal face-centered-cubic (FCC) lattice has been studied. Molecular dynamics (MD) simulations using an embedded-atom (EAM) potential for copper have been performed at room temperature and using strain controlling with high strain rates ranging from 10^7/sec to 10^10/sec. Strain-rates of these magnitudes can be studied experimentally, e.g. using shock waves induced by laser ablation. Void growth has been simulated in three different conditions, namely uniaxial, biaxial, and triaxial expansion. The response of the system in the three cases have been compared in terms of the void growth rate, the detailed void shape evolution, and the stress-strain behavior including the development of plastic strain. Also macroscopic observables as plastic work and porosity have been computed from the atomistic level. The stress thresholds for void growth are found to be comparable with spall strength values determined by dynamic fracture experiments. The conventional macroscopic assumption that the mean plastic strain results from the growth of the void is validated. The evolution of the system in the uniaxial case is found to exhibit four different regimes: elastic expansion; plastic yielding, when the mean stress is nearly constant, but the stress-triaxiality increases rapidly together with exponential growth of the void; saturation of the stress-triaxiality; and finally the failure.Comment: 35 figures, which are small (and blurry) due to the space limitations; submitted (with original figures) to Physical Review B. Final versio

The Sedimentological Significance and Stratigraphic Position of Coarse-Grained Red Beds (?Oligocene) of the Northwestern Margin of Mt. Pozeska Gora (North Croatia)

Coarse-grained clastic sediments of rhyolitic-granitic composition which are associated with the magmatic complex of Mt. Pozeska Gora were previously designated as granites. They are deposited in a continental environment or, more precisely, in an alluvial fan or proximal parts of a braided river system, or in rapid mountain streams during a strong rainfalls. According to their spatial relationship with respect to surrounding Upper Cretaceous granites and rhyolites and Ottnangian sediments; and considering the facies characteristics, we assume that these sediments belong to the Oligocene

Higijenska kvaliteta mlijeka u Sloveniji s obzirom na nazočnost penicilina

Već gotovo dva decenija upotrebljavaju veterinari penicilin za liječenje zaraznih bolesti mliječnih goveda. Velike količine penicilina služe osobito pri terapiji mastitisa: penicilin se u tom slučaju aplicira infuzijom kroz sisni kanal. Inače se aplicira pri terapiji drugih zaraznih bolesti i/m, i/v i p/o za liječenje i preveniranje bolesti, pa kao dodatak krmivu. Dakako, posljedica svega toga jest da se penicilin izlučuje s mlijekom ne samo poslije i/mm nego i poslije i/m i i/v aplikacije

Higijenska kvaliteta mlijeka u Sloveniji s obzirom na nazočnost penicilina

Već gotovo dva decenija upotrebljavaju veterinari penicilin za liječenje zaraznih bolesti mliječnih goveda. Velike količine penicilina služe osobito pri terapiji mastitisa: penicilin se u tom slučaju aplicira infuzijom kroz sisni kanal. Inače se aplicira pri terapiji drugih zaraznih bolesti i/m, i/v i p/o za liječenje i preveniranje bolesti, pa kao dodatak krmivu. Dakako, posljedica svega toga jest da se penicilin izlučuje s mlijekom ne samo poslije i/mm nego i poslije i/m i i/v aplikacije