Reversible inhibition of reproduction during regeneration of cerebral ganglia and celomocytes in the earthworm Dendrobaena veneta

Earthworms may be subjected to mechanical/chemical stimuli and/or sub-lethal predator attacks leading to the extrusion of celomocytes and/or loss of body parts; thus, regeneration of cells, tissues and organs has adaptive value. The aim of present study on the lumbricid earthworm Dendrobaena veneta was to determine the interactive effects of celomocytes and the brain on the regeneration of either system after experimental depletion or extirpation, and to assess the effects of such treatments on reproductive performance. Decerebration was achieved either by amputating the first six anterior segments, or by surgery; celomocyte depletion was achieved by a standard electro-stimulation procedure. Celomocytes (amebocyte and eleocytes, respectively) were counted by hemocytometry, and riboflavin content in celomocyte lysates measured by spectrofluorimetry. The main findings were: (i) D. veneta regenerated anatomically intact brain, including neurosecretory cells, within 10 - 18 weeks after its removal plus celomocyte depletion (i.e. dual treatment); (ii) amoebocyte counts recovered to control levels by 10 weeks after extrusion treatment alone, but were still lower (60 %) than in controls at 18 weeks after dual treatment; eleocyte recovery after electro-stimulation alone was slow, reaching control levels only after 18 weeks, and was further retarded (31 % of controls at 18 weeks) by brain extirpation; (iii) riboflavin content was lower than controls only in the dual-treatment worms at 5 weeks; riboflavin content relative to eleocyte numbers was initially higher than controls in both treatment groups; this index was restored to control levels by 18 weeks in the electro-stimulation only treatment whilst recovery was somewhat retarded in the brain-extirpated group; (iv) celomocyte depletion treatment alone slightly impaired reproductive output, whilst brain removal had pronounced and protracted inhibitory effects. The observations engender the hypothesis that brain-derived neurosecretions and immune-competent celomocytes act in tandem to modulate neural regeneration and reproduction

A composite functional equation from algebraic aspect

In this paper we discuss the composite functional equation f(x+2f(y))=f(x)+y+f(y) on an Abelian group. This equation originates from Problem 10854 of the American Mathematical Monthly. We give an algebraic description of the solutions on uniquely 3-divisible Abelian groups, and then we construct all solutions f of this equation on finite Abelian groups without elements of order 3 and on divisible Abelian groups without elements of order 3 including the additive group of real numbers

On some generalizations of Gołąb-Schinzel functional equation

Composite functional equations in several variables generalizing the Gołąb-Schinzel equation are considerd and some simple methods allowing us to determine their one-to-one solutions, bijective solutions or the solutions having exactly one zero are presented. For an arbitrarily fixed real p, the functional equation Φ([pφ(y) + (1−p)]x +[(1−p)φ(x)+p]y) = φ(x)φ(y), x,y ∈ R, being a special generalization of the Gołąb-Schinzel equation, is considered

Equipment of rail traffic engineering laboratory at the Faculty 0f Civil Engineering Cracow University Of Technology

W artykule opisano konfigurację w zakresie sprzętu i oprogramowania stanowisk laboratoryjnych warstwy podstawowej, obejmującej symulatory posterunków ruchu rozmieszczonych na wirtualnej sieci kolejowej. Powstające na Wydziale Inżynierii Lądowej Politechniki Krakowskiej laboratorium inżynierii ruchu kolejowego ma służyć doskonaleniu procesu dydaktycznego, zwłaszcza w zakresie prowadzenia, organizowania i nadzorowania ruchu pociągów. Podstawowym narzędziem informatycznym, wykorzystanym na poszczególnych stanowiskach laboratoryjnych jest symulator prowadzenia ruchu kolejowego isdr.The configuration of hardware and software for laboratory positions of the base layer, which includes simulators, traffic posts located on the virtual rail network have been presented in the article. The rail traffic engineering laboratory setting up at the Faculty of Civil Engineering Cracow University of Technology aims to improve the educational process, especially in conducting, organizing and supervising the movement of trains. The isdr simulator of railway traffic is the main IT tool deployed at different lab positions

Sample scenarios of didactic classes with the use of the ISDR simulator in the Railway Traffic Engineering Laboratory at the Civil Engineering Faculty at the Cracow University Of Technology

W artykule przedstawiono podstawowe informacje dotyczące pracowni laboratoryjnej wyposażonej w symulator prowadzenia ruchu kolejowego i działania urządzeń srk, zaprojektowanej i uruchomionej na Wydziale Inżynierii Lądowej Politechniki Krakowskiej. Przedstawiono funkcjonalność symulatora oraz możliwości szkoleń prowadzonych z jego wykorzystaniem. Omówiono dwa przykładowe scenariusze szkoleń. Wskazano możliwości wykorzystania symulatora nie tylko w procesie dydaktycznym, lecz również dla potrzeb podmiotów szeroko rozumianego rynku kolejowego.The article presents basic information about the laboratory laboratory equipped with the simulator of railway traffic management and operation of srk devices, designed and launched at the Faculty of Civil Engineering of the Cracow University of Technology. The functionality of the simulator and the possibilities of training conducted with its use are presented. Two examples of training scenarios are discussed. The possibilities of using the simulator were indicated not only in the didactic process, but also for the needs of entities in the broadly understood railway market