A total of 23 genotypes belonging to seven tropical food yams and two wild relative species of different origin and coming from two sampling ecological zones (the Republic of Benin in Africa and Guadeloupe in the Caribbean) was analysed for their 13C content. The δ13C values for all yam samples (from -25.39 and -30.07 ‰) indicated that all species had a C3 photosynthetic type. and D. Cornet, J. Sierra, R. Bonhomme.
Activation state of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) is an important parameter determining the rate of net photosynthesis (PN) in situ for which no information is available with reference to altitude. We analyzed activation state along with PN in three plant species and their cultivars grown at low (LA, 1 300 m) and high (HA, 4 200 m) altitudes. No significant change in PN and the initial activity of RuBPCO was obtained with reference to altitude. However, activation state of RuBPCO was reduced significantly in the HA plants as compared to the LA ones. Hence low partial pressure of CO2 prevailing at HA might be responsible for the lower activation state of RuBPCO. and Narinder Kumar, Sanjay Kumar, Paramvir Singh Ahuja.
The effect of different doses of nitrogen (N) on gas exchange, relative chlorophyll (Chl) amount, and the content of N in the aerial biomass of lisianthus was evaluated. The treatments consisted of six different concentrations of N (50, 100, 150, 200, 250, and 300 g m-3 noted as N50, N100, N150, N200, N250, and N300, respectively), applied through the fertirrigation technique. N250 and N300 induced increase in the contents of foliar Chl and N in the aerial biomass, that in turn contributed to an increase of photosynthetic activity in lisianthus. and J. A. Marchese ... [et al.].
This paper introduces plasmonic antennas and deals with the use of electron microscopy to map localized plasmon resonances in metallic nanoparticles. The best spatial and spectral resolution is achieved by using scanning transmission electron microscopy applied simultaneously with spectroscopic methods sensitive to ultraviolet, visible and infrared light, like electron energy loss spectroscopy (EELS) and cathodoluminescence. As an example, we present the mapping of localized plasmon resonances in gold nanospheres and triangular-shaped nanoparticles. and Tento článek, věnovaný problematice plazmonických antén, se zabývá využitím elektronové mikroskopie k mapování lokalizovaných plazmonových rezonancí v kovových nanočásticích. Nejlepšího prostorového a dobrého spektrálního rozlišení je dosaženo použitím rastrovací prozařovací elektronové mikroskopie spolu se spektroskopickými metodami citlivými v oblasti ultrafialového, viditelného a infračerveného světla - spektroskopií energiových ztrát elektronů EELS (Electron Energy Loss Spectroscopy) a katodoluminiscence. Jako příklad uvádíme mapování lokalizovaných plazmonových rezonancí ve zlatých nanokuličkách a nanočásticích trojúhelníkového tvaru.