Phylogeography of the common hamster (Cricetus cricetus): paleoclimatic reconstructions of Late Pleistocene colonization     

Natalia Yu. FEOKTISTOVA  Ilya G. MESCHERSKY  Georgy I. SHENBROT  Andrey Yu. PUZACHENKO  Sergey I. MESCHERSKY  Pavel L. BOGOMOLOV  Alexey V. SUROV 《Integrative zoology》2023,18(3):581-599

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Modeling soil water dynamics in a drip-irrigated intercropping field under plastic mulch     

Xianyue Li  Haibin Shi  Jiří Šimůnek  Xuewen Gong  Zunyuan Peng 《Irrigation Science》2015,33(4):289-302

Intercropping, drip irrigation, and the use of plastic mulch are important management practices, which can, when utilized simultaneously, increase crop production and save irrigation water. Investigating soil water dynamics in the root zone of the intercropping field under such conditions is essential in order to understand the combined effects of these practices and to promote their wider use. However, not much work has been done to investigate soil water dynamics in the root zone of drip-irrigated, strip intercropping fields under plastic mulch. Three field experiments with different irrigation treatments (high T1, moderate T2, and low T3) were conducted to evaluate soil water contents (SWC) at different locations, for different irrigation treatments, and with respect to dripper lines and plants (corn and tomatoes). Experimental data were then used to calibrate the HYDRUS (2D/3D) model. Comparison between experimental data and model simulations showed that HYDRUS (2D/3D) described different irrigation events and SWC in the root zone well, with average relative errors of 10.8, 9.5, and 11.6 % for irrigation treatments T1, T2, and T3, respectively, and with corresponding root mean square errors of 0.043, 0.035, and 0.040 cm³ cm^?3, respectively. The results showed that the SWC in the shallow root zone (0–40 cm) was lower under non-mulched locations than under mulched locations, irrespective of the irrigation treatment, while no significant differences in the SWC were observed in the deeper root zone (40–100 cm). The SWC in the shallow root zone was significantly higher for the high irrigation treatment (T1) than for the low irrigation treatment, while, again, no differences were observed in the deeper root zone. Simulations of two-dimensional SWC distributions revealed that the low irrigation treatment (T3) produced serious severe water stress (with SWCs near the wilting point) in the 30–40 cm part of the root zone, and that using separate drip emitter lines for each crop is well suited for producing the optimal soil water distribution pattern in the root zone of the intercropping field. The results of this study can be very useful in designing an optimal irrigation plan for intercropped fields.  相似文献   

Landscape composition is the major driver of the taxonomic and functional diversity of tropical frugivorous birds     

Bonfim  Fernando César Gonçalves  Dodonov  Pavel  Cazetta  Eliana 《Landscape Ecology》2021,36(9):2535-2547

Landscape Ecology - Anthropogenic land use and cover changes impact biodiversity worldwide. However, ecological groups are differently affected by landscape composition and configuration....  相似文献   

Environment not ‘nativeness’ dictates reproductive trait shifts in Ponto‐Caspian gobies          下载免费PDF全文

Markéta Konečná  Michal Janáč  Kevin Roche  Pavel Jurajda 《Ecology of Freshwater Fish》2016,25(1):167-170

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Downstream drift of round goby (Neogobius melanostomus) and tubenose goby (Proterorhinus semilunaris) in their non‐native area     

Michal Janáč  Luděk Šlapanský  Zdenka Valová  Pavel Jurajda 《Ecology of Freshwater Fish》2013,22(3):430-438

Several Ponto‐Caspian gobiid species have recently expanded their ranges in Europe and North America. This is the first study to demonstrate passive downstream dispersal (drift) of the round goby (Neogobius melanostomus) and tubenose goby (Proterorhinus semilunaris) in newly colonised areas (River Dyje, Danube basin), a factor that could play an important role in their dispersal. Drift duration (i.e. number of dates on which the species was caught) in round goby was longer than that of both native species and tubenose goby, providing a possible advantage. Size of drifting fish was restricted to a narrow range of 6–8 mm and 5–8 mm for round and tubenose goby, respectively. Drift in both species occurred almost completely during hours of darkness (<1 lux) and fish size did not vary throughout the night. In both species, drift density increased significantly during the first hour after dusk. Round goby density gradually decreased up to dawn, while tubenose goby density varied throughout the night with no clear pattern. Drift of early life stages appears to be an important phenomenon that has not received adequate attention in studies of round and tubenose goby ecology and dispersal.  相似文献   

New procedure for the simulation of belowground competition can improve the performance of forest simulation models     

Vladimir Shanin  Raisa Mäkipää  Maxim Shashkov  Natalya Ivanova  Konstantin Shestibratov  Svetlana Moskalenko  Liliya Rocheva  Pavel Grabarnik  Kapitolina Bobkova  Alexey Manov  Andrey Osipov  Elvira Burnasheva  Maria Bezrukova 《European Journal of Forest Research》2015,134(6):1055-1074

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HPLC analysis of rosmarinic acid in feed enriched with aerial parts of Prunella vulgaris and its metabolites in pig plasma using dual-channel coulometric detection     

Jirovský D  Kosina P  Myslínová M  Stýskala J  Ulrichová J  Simánek V 《Journal of agricultural and food chemistry》2007,55(19):7631-7637

This paper describes a sensitive isocratic HPLC/ECD method developed for the determination of rosmarinic acid (RA) in plant material, animal feed, and pig plasma. The plasma sample preparation only includes protein precipitation and adjustment of the pH. The applicability of the method was tested on plasma samples of pigs that were exposed to a 91-day oral intake of RA via feed enriched by aerial parts of Prunella vulgaris. The plasma was directly analyzed using the method described as well as after enzymatic hydrolysis. When no hydrolysis step was included, RA and caffeic acid (CA) were quantified in the plasma. In hydrolyzed plasma samples, several other metabolites were determined, including dihydrocaffeic, ferulic, and dihydroferulic acid. The dual-channel coulometric detection employed, as an alternative to mass spectrometry, offers good selectivity and sensitivity owing to the electrochemical properties of the phenolic constituents.  相似文献   

Endogenous development of Hemolivia mauritanica (Apicomplexa: Adeleina: Haemogregarinidae) in the marginated tortoise Testudo marginata (Reptilia: Testudinidae): evidence from experimental infection     

Siroký P  Kamler M  Frye FL  Fictum P  Modrý D 《Folia parasitologica》2007,54(1):13-18

Six young tortoises Testudo marginata Schoepff, 1792 were experimentally infected with Hemolivia mauritanica (Sergent et Sergent, 1904). The prepatent period ranged from 6 to 8 weeks. Young, smaller, club-like forms (6-9 x 3-6 Am) of gametocytes appeared in the peripheral blood first, whereas mature, elongated, cylindrical forms (9-12 x 5-7 Am) were detected after 1-2 weeks and predominated during later patency. Three of the infected tortoises were euthanized and dissected to study the endogenous stages. Meronts occurred in the cells of the reticulo-endothelial system and in the erythrocytes; these were observed mostly in parenchymatous organs. Mature forms measured 14.2 x 9.3 microm and contained 7-12 merozoites. Cysts with two (exceptionally one) cystozoites were also found predominantly in parenchymatous organs and measured 14.8 x 7.9 microm. Pathological changes attributable to Hemolivia were mild and limited to liver and kidneys. The role of individual developmental stages of haemogregarines is discussed with respect to evolution of heteroxenous life cycle and long-term persistence of parasites in their intermediate hosts.  相似文献   

Specific contrast ultrasound using sterically stabilized microbubbles for early diagnosis of thromboembolic disease in a rabbit model     

Michal Vla?ín  Robert Luká?  Zuzana Kauerová  Pavel Kohout  Josef Ma?ek  Eli?ka Bartheldyová  ?těpán Koudelka  Zina Korvasová  Jana Plocková  Nikola Hronová  Jaroslav Turánek 《Canadian journal of veterinary research》2014,78(2):133-139

Specific contrast ultrasound is widely applied in diagnostic procedures on humans but remains underused in veterinary medicine. The objective of this study was to evaluate the use of microbubble-based contrast for rapid ultrasonographic diagnosis of thrombosis in small animals, using male New Zealand white rabbits (average weight about 3.5 kg) as a model. It was hypothesized that the use of microbubble-based contrast agents will result in a faster and more precise diagnosis in our model of thrombosis. A pro-coagulant environment had been previously established by combining endothelial denudation and external vessel wall damage. Visualization of thrombi was achieved by application of contrast microbubbles [sterically stabilized, phospholipid-based microbubbles filled with sulfur hexafluoride (SF₆) gas] and ultrasonography. As a result, rapid and clear diagnosis of thrombi in aorta abdominalis was achieved within 10 to 30 s (mean: 17.3 s) by applying microbubbles as an ultrasound contrast medium. In the control group, diagnosis was not possible or took 90 to 180 s. Therefore, sterically stabilized microbubbles were found to be a suitable contrast agent for the rapid diagnosis of thrombi in an experimental model in rabbits. This contrast agent could be of practical importance in small animal practice for rapid diagnosis of thrombosis.  相似文献   

Bioaccumulation and Effects of Heavy Metals in Crayfish: A Review     

Antonín Kouba  Miloš Buřič  Pavel Kozák 《Water, air, and soil pollution》2010,211(1-4):5-16

Metal pollution is a global problem which represents a growing threat to the environment. Because of bioaccumulation and negative effects of heavy metals, their bioavailability needs to be monitored. Many studies showed accumulation of metals in crayfish tissues as dose- and time-dependent without significant differences in tissue concentration levels comparing males and females. Muscles and exoskeleton were considered as specific for accumulation of mercury and nickel, respectively. Cadmium, zinc, copper, lead, and chromium accumulated mainly in hepatopancreas. By analyzing these specific tissues, it is possible to deduce the bioavailability and, by presumption, the level of environmental pollution by specific metals. However, in the case of zinc and copper, their utility is limited to assessing bioavailability because rapid depuration of these metals renders them less useful for long-term environmental monitoring programs. The literature reporting heavy metal impacts on freshwater crayfish, with reference to accumulation levels, is reviewed and summarized with respect to their suitability as bioindicators. Summarized published data from unpolluted or control localities can be used as referential values in crayfish, and consequently help with evaluation of monitored sites.  相似文献