A rotating black and white disc which causes the perception of colours is a remarkable phenomenon and as such has been the object of research for more than a century. The disc carries the name of its creator, a toy maker Charles E. Benham. The colours the disc can produce, varying from orange to blue or purple and including others as well, are not real. The exact place in the visual apparatus where these colours are generated has not been revealed yet but mostly it is considered to be related to the retina. However, as the newest papers indicate, the interactions within the retina itself are not sufficient to fully explain the phenomenon. The colours seen on the disc are called subjective colours or patterns induced flicker colours. Their tint, brightness or intensity are influenced by different conditions. The position of the arcs within the white part of the disc, the width of the arcs, speed of rotation or illumination of the disc and other parameters are all important. and Pozoruhodný jev, kdy rotující černobílý kotouč vyvolává vjem barev, pojmenovaný po výrobci hraček Charlesi E. Benhamovi, je předmětem zkoumání více jak jedno století. Na kotouči mohou být viděny barvy jako je oranžová, modrá, fialová a další, ve skutečnosti jsou však jen zdánlivé. Místo ve zrakovém aparátu, které způsobuje jejich vznik, dosud není odhaleno. Nejčastěji je jejich původ vztahován k sítnici. Jak se ale ukazuje v novějších studiích, samotné sítnicové interakce jsou pro úplné vysvětlení jevu nedostatečné. Barvy viděné na disku se označují jako subjektivní nebo ''vzorem vyvolané blikající barvy''. Jejich odstín, jas či intenzita jsou ovlivněny různými parametry. Důležitá je poloha prstenců v rámci bílé plochy kotouče, jejich tloušťka, rychlost otáčení disku, osvětlení a další.
The review is devoted to the outstanding contributions to the path of carbon in photosynthesis by Professor Emeritus Andrew A. Benson, on the occasion of his death at the age of 97, on January 16, 2015. Benson is the legendary co-discoverer of the photosynthetic reductive pentose phosphate cycle, known to every student of photosynthesis as the Benson-Bassham-Calvin cycle. This pathway evolved into the dominant assimilation mechanism for atmospheric carbon into metabolites. The fundamental ecological and biochemical optimization and evolutionary stability of this mechanism unfolded elegantly in Benson’s hands, as he was the first to recognize the building blocks for the synthesis of essential organic compounds that satisfy the energetic needs and demands of most life forms. Photosynthetic carbon metabolism together with other energy and oxidative reactions and secondary biosynthetic processes are critical for the formation of organic matter; and, thereby, the Benson-Bassham-Calvin cycle ensures maintenance of the biosphere., K. Biel, I. Fomina., and Obsahuje bibliografii
Benzoxazolin-2-(3H)-one (BOA) has been tested in many plants species, but not in soybean (Glycine max). Thus, a hydroponic experiment was conducted to assess the effects of BOA on soybean photosynthesis. BOA reduced net photosynthetic rate, stomatal conductance, and effective quantum yield of PSII photochemistry without affecting intercellular CO2 concentration or maximal quantum yield of PSII photochemistry. Results revealed that the reduced stomatal conductance restricted entry of CO2 into substomatal spaces, thus limiting CO2 assimilation. No change found in intercellular CO2 concentration and reduced effective quantum yield of PSII photochemistry revealed that CO2 was not efficiently consumed by the plants. Our data indicated that the effects of BOA on soybean photosynthesis occurred due to the reduced stomatal conductance and decreased efficiency of carbon assimilation. The accumulation of BOA in soybean leaves reinforced these findings. and Obsahuje bibliografii
Louis Cazamian develops Henri Bergson’s concise remarks, which show humour as a special sort of comical transposition of language. Cazamian stresses that humour is based on transposition, which is inevitably conscious, and he is concerned with the division of humour into four different species according to the modes of transposition. Cazamian focuses especially on the complexity of humour and its impact. Even if a certain view of the world and life, that is, a kind of “matter” of humour, is obviously suggested by the mechanism of transposition, that is, by the “form” of humour, it is impossible to determine any universal rule describing the relationship between matter and form. In that sense Cazamian emphasizes the indefinability of humour, and points to the indeterminability of the humorous effect. These arguments demonstrate the essential influence that many important themes of Bergson’s aesthetics and philosophy have had on Cazamian’s conception of humour, a conception that proves to be integrally Bergsonian.