What do biological powerhouses look like? How do they work? Why does generating a single “dose of energy” demand a highly complicated process? Why do seeds age? Answers to all these questions are to be found in one of the most complex cellular organelles: the mitochondrion.

Operation of an electrically controlled beam steering device based on Rochon prism made by use of nematic liquid crystal is modelled numerically. Deflection angles and angular distribution of light intensity in the deflected beam are calculated. Dynamics of the device is studied. Advantage of application of dual frequency nematic liquid crystal is demonstrated. Role of flexoelectric properties of the nematic is analyzed.

A method for frequency-multiplexed multi-sample gas sensing is presented. It enables measuring multiple samples placed simultaneously in the setup, without any optical or mechanical switching. Samples are measured using heterodyne detection and signal from each sensing path is encoded at different carrier frequency. Subsequently, a signal from particular sample is retrieved through heterodyne beatnote demodulation at unique frequency. This technique is particularly suitable for real-time calibration of the sensor through a sequential (or simultaneous) detection of three signals: from unknown sample, reference sample and baseline. Basic setup is demonstrated and proof-of-concept experiments are presented. Very good agreement with spectra measured using standard tunable diode absorption spectroscopy is obtained.

As one of the sources of law, the Constitution of the Polish Republic mentions ,,instruments of local law" issued by, among others, the directors of maritime public institutions, on the basis of legal authorization. The first, and hitherto only, postconstitutional piece of legislation referring to instruments of local law produced by the directors of maritime public institutions is that of2000 concerning maritime safety. This settlement of the matter gives rise to some doubts on the grounds of constitutionality and of its accordance with the principles of legislative methods. It requires reworking. This article indicates directions that such reworking could take.

Jak wygląda i jak działa biologiczna elektrownia? Dlaczego produkcja „cząsteczki energii” stanowi tak skomplikowany proces? Dlaczego nasiona się starzeją i czy jest to konsekwencją zmian klimatu? Odpowiedzi na te pytania związane są z jedną z najbardziej złożonych organelli – mitochondrium.

The problem of the design of a perfect reduced-order unknown-input observer for standard systems is formulated and solved. The procedure of designing the observer using well-known canonical form is proposed and illustrated with a numerical example. Necessary and sufficient conditions for the solvability of the procedure are given.

In this review I analyse a book titled Introduction to Historical Psychology written by Maciej Dymkowski. The book is an attempt to work out foundations of a new discipline combining psychology and history. M. Dymkowski convincingly argues that historians should more often use psychological models in their explanations of different historical phenomena. He argues that especially cognitive social psychology can help to understand mechanisms and processes which govern human behaviour. I agree that it is necessary to include in historical explanations psychologically patterned ways of perceiving, classification, deforming of social reality.