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The study investigated execution tolerances and profile load capacity curves occurring in industrial conditions. Using graphic images of fits expanded by profile load capacity curves, an attempt was made to explain the effect of the profile load capacity curve on the fitting character of the tenon joint.
NC-AFM (non contact atomic force microscopy) was used to observe the surface of triticale starch granules. The method allows to obtain micro-images of high resolution with no sample pretreatment. Surface structures and protrusions or pores found on the surface of triticale starch granules had a broad range of diameters. The existence of flat, smooth regions on the starch granules, with no visible structures, pores or protrusions, was confirmed.
Cercariae of bird schistosomes are traditionally considered to be very similar in their morphological characteristics. In order to solve the problem, we tested some methods which might be suitable for cercarial differentiation. Fourteen isolates of three Trichobilharzia species (T. szidati, T. franki, T. regenti) occurring sympatrically in Central Europe were used. Dimensions of individual cercariae do not represent a useful criterion for identification, because the intraspecific variability exceeds the interspecific one. On the other hand, chaetotaxy appears a promising way for discrimination, although some sensory papillae do not stain sufficiently with silver nitrate. The papillary pattern (i.e. number and relative position of papillae) is specific for all Trichobilharzia species studied by us. Therefore, we compiled an identification key for the three Trichobilharzia species. In addition, we tried to find species-specific surface saccharide epitopes; none of the labeled lectin probes can be used as a speciesspecific marker.
Consideration is given to the structure and function of the adhesive organ in the male and of the protuberances on the surface of the egg in the Broad mite, Poly phagotarsonemus latus . Scanning Electron microscopy is used to reveal these structures. The adhesive organ serves as a sucker in order that males can carry pharate females. It is believed that the protuberances are part of a discontinuous plastron for gaseous exchange.
The investigated types of wheat flour were characterised by varied chemical composition. The sorption properties were assessed on the basis of monolayer capacity, sorption specific surface, total capacity of capillaries in the area of capillary condensation, the most prob-able capillary radius and radius of capillaries subject to filling in the first phase of condensation. The initial data were obtained by the static-desiccation method at 20ºC and 30ºC. The results revealed that the effect of temperature growth on sorption properties of flour is not explicit, although at higher ambient temperature a significant differentiation of sorption properties of individual types of flour is observed, most probably determined by their chemical composition. Sorptivity of wheat flour is correlated to the protein content. On the other hand, the capillary structure is not a feature differentiating individual types of flour.
The study of floral nectary structures of thirteen ornamental apple cultivars examined using light microscope (MS) and scanning electron microscope (SEM) was performed. It was found that nectary glands in the selected cultivars were located in the upper part of the flower receptacle, between the ovary of the pistil and the base of stamen filaments, and they generally belonged to the epimorphic or transitoric type. The nectary surface area, its thickness, the number of glandular tissue layers, the height of epidermal cells of the nectary and the thickness of the outer wall of the epidermis, together with the cuticle, were determined by light microscope. By using SEM, the structure of the surface of nectaries in four ornamental apple cultivars was observed. The epidermis of the upper part of the nectaries was composed of elongated cells of which outer cell wall was covered with a striated cuticle. The remaining part of the nectary was characterised by cells of similar arrangement and shape, but their surface was marked by a thinner and smoother layer of cuticle. Closed or opened stomata were generally situated at the level of the epidermal cells. Their pores were often filled with granular or plate-shaped structures.
Archebakterie stanowią bardzo złożoną, a przez to niezwykle interesującą grupę drobnoustrojów, zarówno ze względu na ich uzdolnienia do zasiedlania rozmaitych środowisk, w tym zwłaszcza ekstremalnych, jak również z powodu specyficznej budowy komponentów komórkowych. W ostatnich latach obserwuje się duży rozwój wiedzy na ich temat, co skutkuje pojawieniem się ogromnej puli mniej lub bardziej szczegółowych publikacji. W literaturze polskojęzycznej brakuje jednak prac przeglądowych ujmujących szerzej temat budowy i fizjologii tych organizmów. Niniejsza praca uzupełnia tę lukę, omawiając wybrane elementy komórek Archaea wyróżniające się unikalną budową lub funkcjami, takie jak warstwa S, ściana komórkowa, błona cytoplazmatyczna oraz różnorodne wypustki komórkowe. Ponadto zwrócono uwagę na niektóre niezwykłe aspekty metabolizmu archebakterii.
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