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2. Fluorescence emission, energy transfer and structure of pliycobílisomes from NostocflagelUforme Born. et Flah. during dissociation
- Creator:
- Lu, Rong-zhao and Liu, Bin
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- Changes in fluorescence emission spectra (293 and 77 K) of phycobilisomes from Nostoc flagelUforme during dissociation in phosphate buffer of various molarity were studied. There were three bands in 77 K fluorescence emission spectra of partly dissociated phycobilisomes: F648, F666 and F686, characteristic of C-phycocyanin (C-PC), allophycocyanin (APC) and allophycocyanin-B (APC-B), respectively. In severely dissociated phycobilisomes, the F666 band was veiy weak, which indicated that linkage between C-PC and APC was severely dissociated, most of the energy trapped by C-PC could not be transferred to APC, but some of it could be transferred directly to APC-B. The phycobiliproteins in these phycobilisomes constitute an energy transfer chain: PEC^C;PC-»APC-»AP^-B. A new model of phycobilisome structure is suggested, in which some C-PC contact directly with APC and others contact with APC-B.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Motion planning in the plane with polygonal obstacles
- Creator:
- Šeda, Miloš
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- motion planning, roadmap method, computational geometry, visibility graph, and Voronoi diagram
- Language:
- English
- Description:
- In robot motion planning the robot should pass around the obstacles, from a given starting position to a given target position, touching none of them, i.e. the goal is to find a collision-free path from the starting to the target position. This task has many specific formulations depending on the shape of obstacles, allowable directions of movements, knowledge of the scene, etc. Research on path planning has yielded many fundamentally different approaches to its solution that can be classified as road map methods (visibility graph method, Voronai diagram) and methods based on a cell decomposition. In the paper, an approach based on Voronoi diagrams is proposed, considering point, straight line and polygonal obstacles in a completely known scene. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Myxobolus lentisuturalis sp. n. (Myxozoa: Myxobolidae), a new muscle-infecting species from the Prussian carp, Carassius gibelio from China
- Creator:
- Dyková, Iva, Fiala, Ivan, and Nie, Pin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Myxozoa, Myxobolidae, new species, morphology, and SSU rDNA
- Language:
- English
- Description:
- A new highly pathogenic muscle-infecting species of the genus Myxobolus Bütschli, 1882 is described from the Prussian carp, Carassius gibelio (Bloch, 1782) using spore morphology and SSU rDNA sequence data. Phylogenetic analyses elucidated relationship of the newly described Myxobolus lentisuturalis to other Myxobolus species and supported its position of an independent species.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Photosynthetic characterization of Australian pitcher plant Cephalotus follicularis
- Creator:
- Pavlovič, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, carnivorous plants, Cephalotus, chlorophyll, chlorophyll fluorescence, pitcher plants, photosynthesis, respiration, and stomatal density
- Language:
- Multiple languages
- Description:
- Australian carnivorous pitcher plant Cephalotus follicularis Labill. produces two types of leaves. During the spring time, the plant produces a foliage type of noncarnivorous leaf called lamina. Later, the second type of leaf is produced - carnivorous pitcher. Using simultaneous measurements of gas exchange and chlorophyll (Chl) fluorescence photosynthetic efficiency of these two distinct forms of leaves were compared. In addition stomatal density, an important component of gas exchange, and Chl concentration were also determined. Pitcher trap had lower net photosynthetic rate (PN) in comparison to noncarnivorous lamina, whereas the rate of respiration (RD) was not significantly different. This was in accordance with lower stomatal density and Chl concentration in the pitcher trap. On the other hand maximum quantum yield of PSII (Fv/Fm) and effective quantum yield of photochemical energy conversion in PSII (ΦPSII) was not significantly different. Nonphotochemical quenching (NPQ) was significantly higher in the lamina at higher irradiance. These data are in accordance with hypothesis that changing the leaf shape in carnivorous plants to make it a better trap generally makes it less efficient at photosynthesis. However, the pitcher of Cephalotus had much higher PN than it was expected from the data set of the genus Nepenthes. Because it is not possible to optimize for contrasting function such as photosynthesis and carnivory, it is hypothesized that Cephalotus pitchers are less elaborated for carnivorous function than the pitchers of Nepenthes. and A. Pavlovič.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. The effects of drought stress and leaf ageing on leaf photosynthesis and electron transport in photosystem 2 in sweet potato (Ipomoea batatas Lam.) cultivars
- Creator:
- Haimeirong and Kubota, F.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll fluorescence, cultivar differences, dry mass, leaf area, non-photochemical quenching, photorespiration, quantum yield, and stomatal conductance
- Language:
- Multiple languages
- Description:
- Of the four tested sweet potato cultivars having different features in growth and yield, cv. Koganesengan (KOG) was sustainable in photosynthetic activity through young to aged leaves under drought. One of the causes for this phenomenon may be stomatal conductance (g s) of this cultivar that was relatively high in both aged and drought-imposed leaves. In these leaves the non-photochemical quenching (NPQ) was low and the quantum yield of photosystem 2 (Φe) was high, compared to those of the other cultivars. This helps to prevent excessive accumulation of chemical energy in leaves and a decrease in photoinhibition damage to the photosynthetic function, by which KOG sustains a relatively high photosynthetic activity under the drought and alleviates functional deterioration caused by leaf age. and Haimeirong, F. Kubota.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public