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Start Over Coverage 135-140

2. Drought stress influences leaf water content, photosynthesis, and water-use efficiency of Hibiscus rosa-sinensis at three potassium concentrations

Creator:
Egilla, J. N., Davies Jr., F. T., and Boutton, T. W.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
carbon isotope discrimination, Chinese hibiscus, stomatal conductance, and transpiration
Language:
Multiple languages
Description:
The influence of drought stress (DS) upon whole-plant water content, water relations, photosynthesis, and water-use efficiency of Hibiscus rosa-sinensis cv. Leprechaun (Hibiscus) plants at three levels of potassium (K) nutritional status were determined after a 21-d gradually imposed DS treatment. Compared to K-deficient plants, adequate K supply improved the leaf water content (LWC) and leaf water relations of Hibiscus by decreasing the Ψ π, and generally sustained rates of net photosynthesis (PN) and transpiration (E), and stomatal conductance (gs), both in DS and non-DS plants. In K-deficient Hibiscus, LWC, turgor potential (Ψ P), and PN, E, and gs as well as instantaneous water-use efficiency, WUE (PN/E) were consistently lower, compared to K-sufficient plants. Carbon isotope discrimination (Δ) was lower (i.e. longterm WUE was greatest) in DS than non-DS plants, but K had no effect on Δ during the 21-d drought treatment period under glasshouse conditions. However, the trend in the Δ value of DS plants suggests that Δ could be a useful index of the response of Hibiscus to DS under glasshouse growing conditions. Thus the incorporation of a properly controlled fertilization regime involving sufficient levels of K can improve the acclimation of PN to low Ψleaf, increase PN/E of Hibiscus, and may have potential benefit for other woody plants species. and J. N. Egilla, F. T. Davies Jr., T. W. Boutton.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Hypobiosis induction alters the protein profile of Osíertagia ostertagi (Nematoda: Trichostrongylidae)

Creator:
Dopchiz, Marcela C., Parma, Alberto E., and Fiel, César A.
Format:
print
Type:
model:internalpart and TEXT
Subject:
Ostertagia ostertagi, bovine, hypobiosis, and proteins
Language:
English
Description:
The appearance of variations in the protein profile of Ostertagia ostertagi (Stiles, 1892) infective larvae (L3), which were induced by hypobiosis triggering factors, was evaluated by means of SDS-PAGE and densitometric analysts. Area integration analyses of their protein profiles was carried out between 66 and 77 kDa. Important quantitative variations were identified in the protein levels of the induced larvae, where a 5.25 fold increase compared to the control was observed. Two 75.4 and 70 kDa protein bands were found which exceeded the control profile by 4.5 and 44 fold, respectively. This fact suggests that the changes brought about in the process of hypobiosis induction are restricted. This work demonstrates changes at a molecular level corresponding with biological changes induced by conditions causing O. ostertagi hypobiosis.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Impact of UV-B radiation on photosynthetic electron transport of Wolffia arrhiza (L.) Wimm.

Creator:
Eichhorn, M., Döhler, G., and Augsten, H.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Wolffia arrhiza (L.) Wimm. plants precultivated under different radiation conditions were exposed to UV-B at low or strong "white" irradiance. Photosynthetíc electron transport (Hill actívity) was more damaged by UV-B under 6 W m"^ than at 15 W m‘2 supplemental "white light" (WR). The inhibitory effect was more pronounced using red radiation (RR) precultivated plants compared to precultívatíon at blue radiation (BR) or WR. Hill reaction in RR grown W. arrhiza with a high growth rate was more affected by UV-B - in comiection with DCMU and 1,5- diphenyl carbazide - than of plants with a low growth rate. No effect was observed using plants precultivated at BR or WR.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8. Obecná teorie relativity středoškolsky. První část. Neeukleidovská geometrie

Creator:
Ryston, Matěj
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
teorie relativity, theory of relativity, 6, and 53
Language:
Czech and English
Description:
Obecná teorie relativity (OTR) je tradičně vnímána jako příliš abstraktní a matematicky složitá na to, aby mohla být vyučována na střední škole. Jedná se ale o velmi zajímavou partii fyziky, se kterou se zvídavý středoškolák setká i mimo školu. Její fascinující a dosud úspěšné astrofyzikální předpovědi, jako jsou černé díry nebo gravitační vlny, z ní činí velmi atraktivní téma pro výuku. Ve čtyřdílném článku si postupně ukážeme, jak je možné v řeči středoškolské matematiky a fyziky a zejména pomocí praktických aktivit a pomůcek představit základní myšlenky OTR, konkrétně proč nám fyzikové "tvrdí", že "gravitace je zakřivení prostoročasu". Jednotlivé články Neeukleidovská geometrie, Geometrický pohled na gravitaci, Dilatace času a GPS a Gravitace jako zakřivení prostoročasu korespondují s postupnými myšlenkovými kroky, které nás mají dovést nejen k lepšímu pochopení OTR, ale v ideálním případě i prohloubit náš zájem o tuto krásnou teorii či fyziku vůbec., General Relativity (GR) is traditionally viewed as being too abstract and mathematically complex to be taught at upper secondary school. It is for students, however, a very interesting and, thanks to its astrophysical predictions, quite appealing part of physics. In the up-coning four-part series we will describe a possible way to introduce the basics of GR using only the language of upper secondary mathematics and physics; in particular, why physicists “tell us” that “gravitation is curvature of spacetime”. Individual articles: non-Euclidean geometry, geometrical view of gravitation, time dilation and GPS, and gravitation as curvature of spacetime correspond to a series of thoughts, which will hopefully lead to a better understanding of GR and ideally, also deepen interest in this beautiful theory as well as physics itself., and Matěj Ryston.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

9. Physiological diversity among the potentially productive branches of regular and irregular bearing mango cultivars

Creator:
Shivashankara, K.S. and Mathai, C.K.
Format:
print
Type:
model:internalpart and TEXT
Subject:
CO2 fixing capacity, mesophyll cells, tree branching, transpiration rate, stomatal conductance, net photosynthetic rate, mesophyll efficiency, Mangifera indica L., and flowering
Language:
Multiple languages
Description:
Within each mango (Mangifera indica L.) tree there is a diversity in flowering ability among its terminál branches. Significant variations in net photosynthetic rate (Pn), transpiration rate, stomatal conductance (gj) and mesophyll efficiency (mesophyll capacity to fix CO2) were observed generally among the productive branches. However, the extent of variation was more pronounced in trees with irregular bearing habits (cv. Langra) as compared to regular bearers (cv. Romani). In generál, correlation coefficients indicated that variations in among n5 branches were mainly due to the mesophyll efficiency and g^, In regular bearing trees, the narrow range of variation in was related to a better mesophyll capacity. This in tum might result in higher carbon build-up of 05 branches which would háve helped them to flower regularly with minimum branch to branch variations.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

10. Pseudocapillaria (Pseudocapillaria) moraveci sp. n. (Nematoda: Capillariidae) from the stomach of Gobius paganellus (Perciformes: Gobiidae) from Vigo estuary (NW Spain)

Creator:
Iglesias, Raúl, Centeno, Luisa, García, Nuria, and García-Estévez, José M.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
intertidal fish, rocky shores, parasites, digestive tract, and taxonomy
Language:
English
Description:
Pseudocapillaria moraveci sp. n. (Nematoda, Capillariidae) is described from the stomach of Gobius paganellus Linnaeus (Perciformes, Gobiidae) from rocky shores of the Vigo estuary (Northwest Atlantic coast of Spain). Scanning electron microscopy reveals the absence of a dorsal cuticular membrane interconnecting the caudal lobes of male, thus confirming the assignment of this new species to the nominotypical subgenus Pseudocapillaria Freitas, 1959. Pseudocapillaria moraveci can be easily differentiated from other marine congeneric species belonging to subgenera Pseudocapillaria and Ichthyocapillaria Moravec, 1982 by its muscular oesophagus, which is distinctly thickened at the distal third, the terminal or almost terminal anus in female, the presence of a basal internal papilla on each ventrolateral caudal lobe in male, and its exclusive site preference for the stomach. In addition, the spicule, which measures 0.180-0.292 mm in length (4.9-7.9% of body length) and possesses a proximal end expanded and oblique in lateral view, a narrowed middle part, and a distal end almost pointed, also distinguishes this species. Pseudocapillaria moraveci is, together with P. tomentosa (Dujardin, 1843) Moravec, 1987, the only species in the genus Pseudocapillaria that has been reported to infect members of the family Gobiidae.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public