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Abstract

Three trackways attributable to the ichnospecies Bifurculapes laqueatus Hitchcock, 1858 found in Lower Jurassic rocks of the Newark Supergroup in northeastern North America are preserved in association with current lineations. Each trackway takes turns so that parts of the trackway parallel the current lineations. This parallelism is interpreted as evidence that the trackmakers were entrained in flowing water and had to change course due to the current. If this interpretation is correct, then morphological differences between B. laqueatus and terrestrial insect trackways could be explained by the trackmaker moving subaqueously. Further, B. laqueatus would constitute only the second insect trackway from this region to be recognized as being made subaqueously. From an ecological standpoint, the aquatic insects that made B. laqueatus were probably near the base of the local food chain, the apex predators of which were piscivorous theropod dinosaurs.

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Patrick R. Getty
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Abstract

The influence of bean seed surface lipids on infestation of seeds by Acanthoscelides obtectus Say was investigated. The experiments were performed in dual-choice bioassays on three bean varieties: Blanka, Bor and Longina. The collected data for natural and solvent washed seeds concerned the number of ovipositions, embryo mortality, lack of seed-boring activity, dead larvae inside seeds and developed insects. The results clearly indicated that bean seed surface lipids are involved in all infestation stages, and could be used to distinguish resistant and non-resistant varieties of been. Chemical analyses revealed the following groups of surface lipids: wax esters, long chain primary alcohols, n-alkanes, sterols, fatty acids, squalene, aldehydes, monoacylglycerols, ketones and fatty acid esters. Quantitative composition of surface lipids was analysed using selected chemometric procedures to determine correlation with bioactivity. Cluster analysis of surface lipid composition enabled to distinguish resistant and non-resistant varieties. Fatty acids and monoacylglycerols were found to deter bean weevil infestation, while alkan-1-ols acted as attractants.

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Authors and Affiliations

Mariusz Nietupski
Beata Szafranek
Dolores Ciepielewska
Elżbieta Synak
Łucja Fornal
Janusz Szafranek
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Abstract

This document contains results of research on complex motion common magnetic circuit electromagnetic converter characteristic that allows making independent axial and rotary shaft motion. The converter in addition to linear-rotary mechanism consists of two drive rotors and one common magnetic circuit excitator. Such a solution allows to reduce volume of the machine and makes it easier to use. The paper cites design intent and possible structure of the device. Phenomenon of common magnetic circuit adverse effect on correct operation of device is discussed. The concept of using relative error as a way to evaluate the influence of that phenomenon in the torques is discussed. Waveforms of determined relative errors for all possible cases is presented. Furthermore the concept of average relative error is defined and its use as a quantitative method of assessing the degree of common circuit impact is indicated. Definition of relative error ripple factor is given, and its usage is shown. Winding inductance calculation based on free FEM application is shown and its influence on control strategy and power system.

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Grzegorz Kamiński
Paweł Góralski
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Abstract

In this work, a design equation was presented for a batch-recirculated photoreactor composed of a packed bed reactor (PBR) with immobilised TiO2-P25 nanoparticle thin films on glass beads, and a continuous-flow stirred tank (CFST). The photoreactor was studied in order to remove C.I. Acid Orange 7 (AO7), a monoazo anionic dye from textile industry, by means of UV/TiO2 process. The effect of different operational parameters such as the initial concentration of contaminant, the volume of solution in CFST, the volumetric flow rate of liquid, and the power of light source in the removal efficiency were examined. A rate equation for the removal of AO7 is obtained by mathematical kinetic modelling. The results of reaction kinetic analysis indicate the conformity of removal kinetics with Langmuir-Hinshelwood model (kL-H = 0.74 mg L-1 min-1, Kads = 0.081 mg-1 L). The represented design equation obtained from mathematical kinetic modelling can properly predict the removal rate constant of the contaminant under different operational conditions (R2 = 0.963). Thus the calculated and experimental results are in good agreement with each other.

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Authors and Affiliations

Behnaz Sheidaei
Mohammad A. Behnajady
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Abstract

School textbooks written by a Spanish erudite and pedagogue Juan Luis Vives were used in schools of Protestant denominations in Royal Prussia – in Gdańsk, Toruń, Elbląg, but also in other towns and cities of the Polish-Lithuanian Commonwealth– for teaching Latin. Nicolaus Volckmar, of German descent, a Polis language teacher at the Academic Gymnasium in Gdańsk, utilized the structure and themes of Vives’ dialogues Exercitatio linguae latinae (1538) for teaching the Polish language. In this manner, paradoxically, the “phrasebook” of the Spanish humanist, as well as its subsequent editions, still in the 18th century was used by Gdańsk schoolers of German origin to learn the language which they needed for everyday communication in the community of multi-cultural and multi-ethnic Gdańsk. The Vives-Volckmar phrasebook was undoubtedly used by Arnold von Holten, later a lifetime mayor of the city, sent on a diplomatic mission to Spain by the Hanseatic League.

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Authors and Affiliations

Joanna Partyka

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