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35992. Wardium paucispinosum sp. n. (Eucestoda: Hymenolepididae), parasite of Larus maculipennis (Aves: Laridae) in Mar dcl Plata, Argentina; with comments on Wardium semiductilis (Szidat, 1964) comb. n.

Creator:
Labriola, Juliana Beatrix and Suriano, Delia Mabel
Format:
print
Type:
model:internalpart and TEXT
Subject:
Eucestoda, Argentina, Laridae, Wardium, and Hymenolepididae
Language:
English
Description:
A new species Wardium paucispinosum (Eucestoda: Hymenolepididae) parasite from the intestine of Larus maculipennis (Lichtenstein) from Mar del Plata, Argentina is described. The distinctive features of the new species are: strobilar length 52.8 mm; 10 aploparaksoid rostellar hooks, 14 (12-17) pm long; ratio between cirrus pouch length and mature proglottid width (CPL/MPW) 0.38 (0.27-0.50); regular cylindrical evaginated cirrus, 90 x 10 pm, with distal end without spines and proximal and medium thirds covered with spines 7 pm long; simple tubular membranous vagina, 110 x 10 pm, without sclcrotised portions and sphincters; eggs fusiform, 77 x 44 pm. Besides, llymenolepis semiductilis Szidat, 1964, from the intestine of Larus dominicanus and L. maculipennis from Santa Fé, Argentina is transferred to the genus Wardium Mayhew, 1925, based on the presence and shape of the rostellar hooks.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

35993. Warming Vistula River - the effects of climate and local conditions on water temperature in one of the largest rivers in Europe

Creator:
Ptak, Mariusz, Sojka, Mariusz, Graf, Renata, Choiński, Adam, Zhu, Senlin, and Nowak, Bogumił
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
water temperature, transit rivers, trends, transformation factors, and Central Europe
Language:
Slovak
Description:
The paper evaluates changes in the water temperature of the Vistula River – one of the longest rivers in Europe. Mean monthly and annual water temperatures from the period 1971–2017 for 11 stations along the entire length of the river revealed the increasing trends. The mean increase in water temperature in the analysed multi-annual period was 0.31 °C dec–1. In the majority of analysed stations, the key factor determining changes in the water temperature of the river was air temperature. The observed water warming in the Vistula River should be considered an exceptionally unfavourable situation in the context of importance of water temperature for a number of processes and phenomena occurring in river ecosystems. Given the scale of changes, fast measures should be undertaken to slow down the warming.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

35994. Warp-speed adaptation to novel hosts after 300 generations of enforced dietary specialisation in the seed beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae)

Creator:
Price, Thomas N., Leonard, Aoife, and Lancaster, Lesley T.
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, brouci, mandelinkovití, beetles, Chrysomelidae, Coleoptera, Bruchinae, Callosobruchus maculatus, emerging crop pests, host shifts, genetic variation, adaptation trajectory, evolvability, experimental evolution, quasi-natural selection, heritability, 2, and 59
Language:
English
Description:
Herbivorous insects are often highly specialised, likely due to trade-offs in fitness on alternative host species. However, some pest insects are extremely adaptable and readily adopt novel hosts, sometimes causing rapid expansion of their host range as they spread from their original host and geographic origin. The genetic basis of this phenomenon is poorly understood, limiting our ability to predict or mitigate global insect pest outbreaks. We investigated the trajectory of early adaptation to novel hosts in a regionally-specialised global crop pest species (the cowpea seed beetle Callosobruchus maculatus). After experimentally-enforced dietary specialisation for nearly 300 generations, we measured changes in fitness over the first 5 generations of adaptation to 6 novel hosts. Of these, C. maculatus reproduced successfully on all but one, with reduced fitness observed on three hosts in the first generation. Loss of fitness was followed by very rapid, decelerating increases in fitness over the first 1-5 generations, resulting in comparable levels of population fitness to that observed on the original host after 5 generations. Heritability of fitness on novel hosts was high. Adaptation occurred primarily via changes in behavioural and phenological traits, and never via changes in offspring survival to adulthood, despite high heritability for this trait. These results suggest that C. maculatus possesses ample additive genetic variation for very rapid host shifts, despite a prolonged period of enforced specialization, and also suggest that some previously-inferred environmental maternal effects on host use may in part actually represent (rapidly) evolved changes. We highlight the need to examine in more detail the genetic architecture facilitating retention of high additive genetic variation for host shifts in extremely adaptable global crop pests., Thomas N. Price, Aoife Leonard, Lesley T. Lancaster., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

35996. Water flow in a single fracture with variable aperture

Creator:
Veselý, Marek and Mls, Jiří
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
fracture flow, variable aperture, percolation probability, contact area, puklinové proudění, proměnlivé rozevření, perkolační pravděpodobnost, and kontaktní plocha
Language:
Slovak
Description:
Water flow in a single fracture with variable aperture was studied by means of numerical modeling. For this purpose, two numerical models were developed. Computer simulations of water flow rates, fracture contact areas and transmissivities for fractal and nonfractal fractures were performed. Water flow rates were approximated by a trend function. The effect of the grid size upon the stability of results as well as the dependence of the fracture transmissivity on rate of contact area were studied. The achieved results were compared with measured data. and Studie se věnuje proudění podzemní vody v samostatné puklině metodou numerického modelování. K tomu účelu jsme vyvinuli dva numerické modely. Byly provedeny série numerických simulací proudění vody a výpočtu kontaktní plochy a transmisivity pukliny pro obecný typ pukliny. Byly studovány vliv velikosti sítě generované pukliny na stabilitu perkolačních charakteristik a závislost propustnosti pukliny na poměrné velikosti kontaktní plochy. Získané výsledky byly vyhodnocovány ve vztahu ke známým experimentálním datům.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

35997. Water relations and gas exchange in Coespeletia moritziana (Sch. Bip) Cuatrec., a giant rosette species of the high tropical Andes

Creator:
Rada, F., Azócar, A., and Rojas-Altuve, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, net photosynthetic rate, osmotic adjustment, plant growth stages, stomatal conductance, tropical mountains, 2, and 58
Language:
Multiple languages
Description:
Giant rosettes are ones of the most striking features of the vegetation in the high tropical Andes, with Coespeletia moritziana reaching the highest altitudes up to 4,600 m a.s.l. Different from other giant rosettes, this species grows on rock outcrops with poorly developed soils and where water availability may be limited. Two questions are addressed in this study: How does this species respond in terms of water relations to maintain favorable gas-exchange conditions? Considering that adult plants rely on a water-reserving central pith, how do early stages respond to this environment’s extreme conditions? Water relations and gas-exchange studies were carried out on juveniles, intermediate and adult C. moritziana plants during wet and dry seasons in Páramo de Piedras Blancas at 4,200 m a.s.l. Adult plants maintained higher leaf water potentials (ΨL) during the wet season, however, no differences between stages were found for the dry season. Minimum dry season ΨL were never near the turgor loss point in any of the stages. Juveniles show a more strict stomatal control during the dry season to maintain a favorable water status. Net photosynthesis significantly decreased in intermediate and juvenile stages from wet to dry seasons. Our results suggest that C. moritziana resists more extreme conditions compared to other Andean giant rosettes., F. Rada, A. Azócar, A. Rojas-Altuve., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

35998. Water relations and leaf anatomy of the tropical species, Jatropha gossypifolia and Alternanthera crucis, grown under an elevated CO2 concentration

Creator:
Rengifo, E., Urich, R., and Herrera, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
drought, parenchyma, open-top chamber, osmotic potential, pressure potential, stomatal density, volumetric elasticity modulus, water potential, and water supply
Language:
Multiple languages
Description:
In order to address the question of how elevated CO2 concentration (EC) will affect the water relations and leaf anatomy of tropical species, plants of Jatropha gossypifolia L. and Alternanthera crucis (Moq.) Bondingh were grown in five EC open top chambers (677 μmol mol-1) and five ambient CO2 concentration (AC) open top chambers (454 μmol mol-1) with seasonal drought. No effect of EC was found on morning xylem water potential, leaf osmotic potential, and pressure potential of plants of J. gossypifolia. In A. crucis EC caused a significant increase in morning xylem water potential of watered plants, a decrease in osmotic potential, and an increase of 24-79 % in pressure potential of moderately droughted plants. This ameliorated the effects of drought. Stomatal characteristics of both leaf surfaces of J. gossypifolia and A. crucis showed time-dependent, but not [CO2]-dependent changes. In J. gossypifolia the thickness of whole leaf, palisade parenchyma, and spongy parenchyma, and the proportion of whole leaf thickness contributed by these parenchymata decreased significantly in response to EC. In A. crucis EC caused an increase in thickness of whole leaf, bundle sheath, and mesophyll, while the proportion of leaf cross-section comprised by the parenchymata remained unchanged. These effects disappeared with time under treatment, suggesting that acclimation of the leaf anatomy to the chambers and to EC took place in the successive flushes of leaves produced during the experiment. and E. Rengifo, R. Urich, A. Herrera.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

35999. Water relations, chlorophyll a fluorescence, and contents of saccharides in tree species of a tropical forest in response to flood

Creator:
Rengifo, E., Tezara, W., and Herrera, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Acosmium nitens, Campsiandra laurifolia, Eschweilera tenuifolia, net photosynthetic rate, Psidium ovatifolium, soluble sugars, starch, stomatal conductance, and Symmeria paniculata
Language:
Multiple languages
Description:
We studied the seasonal changes in water relations, chlorophyll a fluorescence, and leaf saccharide contents of the tropical flood-tolerant trees Acosmium nitens, Campsiandra laurifolia, Eschweilera tenuifolia, Symmeria paniculata, and Psidium ovatifolium. Xylem water potential increased with flooding to a larger extent than leaf sap osmotic potential in all the species, and soluble sugars contributed up to 66 % of osmotic potential at maximum flooding. Starch was accumulated in leaves. Maximum quantum yield of photosystem 2 decreased in emerged leaves, values being always higher than 0.76. Daily maximum net photosynthetic rate and leaf conductance decreased in all the species. This reduction was associated in all the species but S. paniculata with the absence of a compensatory increase in non-photochemical quenching. and E. Rengifo, W. Tezara, A. Herrera.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

36000. Water relations, gas exchange, photochemical efficiency, and peroxidative stress of four plant species in the Heihe drainage basin of northern China

Creator:
Gong, J. R., Zhao, A. F., Huang, Y. M., Zhang, X. S., and Zhang, C. L.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
active oxygen, antioxidative ability, desert plants, drought stress, mesophytic plants, photochemical efficiency, photosynthesis, stomatal conductance, transpiration rate, and water use efficiency
Language:
Multiple languages
Description:
Haloxylon ammodendron, Calligonum mongolicum, Elaeagnus angustifolia, and Populus hosiensis had different adaptations to limited water availability, high temperature, and high irradiance. C. mongolicum used water more efficiently than did the other species. Because of low transpiration rate (E) and low water potential, H. ammodendron had low water loss suitable for desert conditions. Water use efficiency (WUE) was high in E. angustifolia, but high E and larger leaf area made this species more suitable for mesic habitats; consequently, this species is important in tree shelterbelts. P. hosiensis had low WUE, E, and photosynthesis rates, and therefore, does not prosper in arid areas without irrigation. High irradiances caused photoinhibition of the four plants. The decrease of photochemical efficiency was a possible non-stomata factor for the midday depression of C. mongolicum. However, the species exhibited different protective mechanisms against high irradiance under drought stress. H. ammodendron and C. mongolicum possessed a more effective antioxidant defence system than E. angustifolia. These three species showed different means of coping with oxidative stress. Hence an enzymatic balance is maintained in these plants under adverse stress conditions, and the concerted action of both enzymatic and non-enzymatic reactive oxygen species scavenging mechanisms is vital to survive adverse conditions. and J. R. Gong ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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