Modern pollen rain in heathlands and adjacent forest phytocoenoses in Northern and Central Poland

Differences between modern pollen rains in three types of phytocoenoses were studied in two regions, i.e. Tuchola Forest and Toruń Basin. The phytocoenoses in question were heaths, young pine-birch growths and mature pine tree stands, which form a temporal sequence and spatial mosaic in the landscape. In order to compare the structure of pollen samples, phytocoenoses and the landscape, the methods of numerical taxonomy were applied. An increase in the average number of sporomorphs was recorded, as well as in the taxonomic diversity of the pollen spectrum in this temporal sequence arranged from non-forest communities through young growths to mature forests. In the subsequent developmental stages, also the percentage contribution of Pinus pollen increased, as well as the total contribution of arboreal pollen (AP). The increase in the percentage contribution of arboreal pollen is accompanied by the decrease in the contribution of non-arboreal pollen (NAP), including Calluna and Ericaceae. Also a small increase in the number of species was observed. With the increased pine domination, however, the diversity of pollen types (expressed by rarefaction and Shannon-Wiener indices) decreases. As a result of the performed analyses, it was also found that the species composition of phytocoenoses and a pollen spectrum differs considerably, because the import of pollen from further areas exerts a significant influence on the structure of a palynological sample. The genus Calluna is the only type of plants characterized by a strong relationship between the occurrence in a phytocoenosis and in a surface pollen sample. Similarity between the taxa composition of a pollen spectrum and the landscape structure, consisting of a mosaic of phytocoenoses, seems to be higher than between a pollen sample and a phytocoenosis from which that sample was collected. The latter thesis, however, needs to be confirmed by further researches

Modern pollen rain in heathlands and adjacent forest phytocoenoses in Northern and Central Poland

Differences between modern pollen rains in three types of phytocoenoses were studied in two regions, i.e. Tuchola Forest and Toruń Basin. The phytocoenoses in question were heaths, young pine-birch growths and mature pine tree stands, which form a temporal sequence and spatial mosaic in the landscape. In order to compare the structure of pollen samples, phytocoenoses and the landscape, the methods of numerical taxonomy were applied. An increase in the average number of sporomorphs was recorded, as well as in the taxonomic diversity of the pollen spectrum in this temporal sequence arranged from non-forest communities through young growths to mature forests. In the subsequent developmental stages, also the percentage contribution of Pinus pollen increased, as well as the total contribution of arboreal pollen (AP). The increase in the percentage contribution of arboreal pollen is accompanied by the decrease in the contribution of non-arboreal pollen (NAP), including Calluna and Ericaceae. Also a small increase in the number of species was observed. With the increased pine domination, however, the diversity of pollen types (expressed by rarefaction and Shannon-Wiener indices) decreases. As a result of the performed analyses, it was also found that the species composition of phytocoenoses and a pollen spectrum differs considerably, because the import of pollen from further areas exerts a significant influence on the structure of a palynological sample. The genus Calluna is the only type of plants characterized by a strong relationship between the occurrence in a phytocoenosis and in a surface pollen sample. Similarity between the taxa composition of a pollen spectrum and the landscape structure, consisting of a mosaic of phytocoenoses, seems to be higher than between a pollen sample and a phytocoenosis from which that sample was collected. The latter thesis, however, needs to be confirmed by further researches

Unique Role of Vimentin Networks in Compression Stiffening of Cells and Protection of Nuclei from Compressive Stress

In this work, we investigate whether stiffening in compression is a feature of single cells and whether the intracellular polymer networks that comprise the cytoskeleton (all of which stiffen with increasing shear strain) stiffen or soften when subjected to compressive strains. We find that individual cells, such as fibroblasts, stiffen at physiologically relevant compressive strains, but genetic ablation of vimentin diminishes this effect. Further, we show that unlike networks of purified F-actin or microtubules, which soften in compression, vimentin intermediate filament networks stiffen in both compression and extension, and we present a theoretical model to explain this response based on the flexibility of vimentin filaments and their surface charge, which resists volume changes of the network under compression. These results provide a new framework by which to understand the mechanical responses of cells and point to a central role of intermediate filaments in response to compression

Identification of Influence of Part Tolerances of 3PWR-SE Pump On Its Total Efficiency Taking Into Consideration Multi-Valued Logic Trees

This paper presents the way of identifying the influence of the tolerance of model pumps (TYPE 3PWR-SE) construction on the total efficiency. The identification of sensitive control dimensions (Value/Tolerance) of examined pumps has been made by means of the multi-valued logic and inductive decision trees. In order to confirm the obtained results, multiple-valued logic trees have been used in the paper according to algorithms for the minimization of individual logic functions. What is more, a specific monotonicity of values of the most key parameters has been determined for the investigated set of pumps having individual specification numbers

Analysis of a dimensional tolerances’ series of 2PW-SE gear pumps using multi valued logical trees

Gear pumps of a prototype series 2PW-SEW belonging to II group were the research object. Wrocław University of Technology in co-operation with the company HYDROTOR S.A. designed the units. The experimental pump has been designed with taking into consideration technological possibilities of the company HYDROTOR S.A. The innovation of the prototype unit is based on using oblique gears with an involute tooth modified in the lower and upper part of the profile. The modification in the lower part was made using the so-called tooth root undercutting. Multivalent logic trees with designated rank of importance parameters structural/operational were used, considering the effect of tolerances construction. The area has been increased by cutting the oblique teeth. In order to determine the influence of the manufacturing technology on the level of the emitted noise, it has been decided to make gears using the shaving technology

Hydraulic Tests of the PZ0 Gear Micropump and the Importance Rank of Its Design and Operating Parameters

This article presents the results of hydraulic tests performed for a prototype gear micropump of a new design. The development of modern hydraulic systems is following two directions: the integration of hydraulic and electronic engineering and a reduction in the mass and the dimensions of the system. The scope of this research involved identifying static characteristics of the prototype gear pump, i.e., its efficiency, torque and power. The tests were performed for PZ0 pumps with the following specific deliveries (which are their design parameters), 0.25 cm3/rev, 0.315 cm3/rev, 0.5 cm3/rev, 0.8 cm3/rev, and 1.0 cm3/rev—with two different types of hydraulic oils, Azolla ZS 22 and HL 68. The operating parameters included the rotational speed, the discharge pressure and the flow rate. The obtained research results suggest an application of the decision tree induction-based classification method for identifying the most important design and operating parameters and their values influencing total efficiency. In addition, the article investigates the influence of rotational speed and specific delivery on total efficiency. The total efficiency translates indirectly into the energy consumption of the solution. The criterion of energy consumption is a key parameter for ecological and economical reasons, related mainly to future operating costs

Analysis of a dimensional tolerances’ series of 2PW-SE gear pumps using multi valued logical trees

Gear pumps of a prototype series 2PW-SEW belonging to II group were the research object. Wrocław University of Technology in co-operation with the company HYDROTOR S.A. designed the units. The experimental pump has been designed with taking into consideration technological possibilities of the company HYDROTOR S.A. The innovation of the prototype unit is based on using oblique gears with an involute tooth modified in the lower and upper part of the profile. The modification in the lower part was made using the so-called tooth root undercutting. Multivalent logic trees with designated rank of importance parameters structural/operational were used, considering the effect of tolerances construction. The area has been increased by cutting the oblique teeth. In order to determine the influence of the manufacturing technology on the level of the emitted noise, it has been decided to make gears using the shaving technology

Analysis of Dimensional Tolerances on Hydraulic and Acoustic Properties of a New Type of Prototypal Gear Pumps

This study focuses on the construction of a prototype series of pumps. The technological capabilities of the entire series of gear pumps with a three-poly-involute outline were determined. We developed neural networks to analyze the dimensional tolerance and composition of the pump components and impact on the distribution for the constructed units. The most crucial dimensions to control were then determined—namely, dimensional and form tolerance were necessary—with a reduction in accuracy classification where it is less important. Measurements of acoustic quantities and of vibrations were also carried out. In conclusion, after positive verification, printed polyethylene wheels can be manufactured in greater, mass-produced quantities. Optimization techniques can then be applied, leading to reduced manufacturing costs and increased efficiency

Hydraulic Tests of the PZ0 Gear Micropump and the Importance Rank of Its Design and Operating Parameters

This article presents the results of hydraulic tests performed for a prototype gear micropump of a new design. The development of modern hydraulic systems is following two directions: the integration of hydraulic and electronic engineering and a reduction in the mass and the dimensions of the system. The scope of this research involved identifying static characteristics of the prototype gear pump, i.e., its efficiency, torque and power. The tests were performed for PZ0 pumps with the following specific deliveries (which are their design parameters), 0.25 cm3/rev, 0.315 cm3/rev, 0.5 cm3/rev, 0.8 cm3/rev, and 1.0 cm3/rev—with two different types of hydraulic oils, Azolla ZS 22 and HL 68. The operating parameters included the rotational speed, the discharge pressure and the flow rate. The obtained research results suggest an application of the decision tree induction-based classification method for identifying the most important design and operating parameters and their values influencing total efficiency. In addition, the article investigates the influence of rotational speed and specific delivery on total efficiency. The total efficiency translates indirectly into the energy consumption of the solution. The criterion of energy consumption is a key parameter for ecological and economical reasons, related mainly to future operating costs