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30572. Survival, body mass and potential fecundity of the invasive moth Cameraria ohridella (Lepidoptera: Gracillariidae) on its original host plant Aesculus hippocastanum and Aesculus glabra
- Creator:
- Walczak, Urszula, Baraniak, Edward, and Zduniak, Piotr
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, motýli, vzpřímenkovití, klíněnka jírovcová, butterflies, Gracillariidae, Cameraria ohridella, Lepidoptera, invasive species, leaf miner, herbivore performance, Aesculus hippocastanum, Aesculus glabra, 2, and 59
- Language:
- English
- Description:
- Performance of the invasive horse-chestnut leaf miner, Cameraria ohridella Deschka & Dimic, 1986 (Lepidoptera: Gracillariidae), was studied on two host plants: the white-flowering horse-chestnut Aesculus hippocastanum L. and the Ohio buckeye Aesculus glabra Willd. C. ohridella developed successfully on both host plants; however, mine density and survival were much higher on A. hippocastanum than on A. glabra. The pupal mass and potential fecundity were strongly affected by the host plant on which the larvae fed. On A. hippocastanum pupae were significantly heavier and females more fecund than those on A. glabra. Furthermore, on both host plants there was a significant positive correlation between the number of oocytes in ovaries and pupal body mass, and as a consequence, heavier females produced more eggs. Our study demonstrates that the mine density, survival, pupal mass and potential fecundity were significantly lower on A. glabra than on A. hippocastanum. The observed lower performance of C. ohridella on the exotic host plant was assumed to be due to its poor food quality (nutritional and chemical composition)., Urszula Walczak, Edward Baraniak, Piotr Zduniak., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30573. Susan Wolf on supererogation and the dark side of morality
- Creator:
- Grigore, Nora
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- morality, moral saints, and supererogation
- Language:
- Slovak
- Description:
- Wolf proposes supererogation as a solution for curbing the exaggerated demands of morality. Adopting supererogation is supposed to prevent us from considering that all morally good deeds are obligatory. Supererogation, indeed, makes some morally good deeds merely optional, saving the agent from the requirement of behaving as much as possible like a Moral Saint. But I argue that Wolf cannot use supererogation in service of her overall project, for two reasons. First, because implied in the concept of supererogation is that going beyond duty adds to our humanity rather than detract from it (as Wolf argues). Secondly, after analyzing attempts to acclimatize supererogation in other theoretical frameworks, I conclude that supererogation can limit morality’s claims only if Wolf’s reasons of “individual perfection” can defeat moral reasons. I argue that a common scale of evaluation between moral and non-moral reasons is needed for their comparison, but Wolf explicitly rejects this way out.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30574. Susceptibility of an ascorbate-deficient mutant of Arabidopsis to high-light stress
- Creator:
- Zeng, L.-D., Li, M., Chow, W. S., and Peng, C.-L.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- huseníček rolní, kyselina askorbová, Arabidopsis thaliana, ascorbic acid, high-light stress, chlorophyll fluorescence, reactive oxygen species, 2, and 581
- Language:
- Multiple languages
- Description:
- Ascorbate is an important antioxidant involved in both enzymatic and nonenzymatic reactions in plant cells. To reveal the function of ascorbate associated with defense against photo-oxidative damage, responses of the ascorbate-deficient mutant vtc2-1 of Arabidopsis thaliana to high-light stress were investigated. After high-light treatment at 1,600 μmol(photon) m-2 s-1 for 8 h, the vtc2-1 mutant exhibited visible photo-oxidative damage. The total ascorbate content was lower, whereas accumulation of H2O2 was higher in the vtc2-1 mutant than that in the wild type. The chlorophyll (Chl) content and PSII Chl fluorescence parameters, such as maximal quantum yield of PSII photochemistry, yield, and electron transport rate, in vtc2-1 mutant decreased more than that in the wild type, whereas the nonphotochemical quenching coefficient increased more in the wild type than that in vtc2-1 mutant. Therefore, the vtc2-1 mutant was more sensitive to high-light stress than the wild type. Accumulation of reactive oxygen species was mainly responsible for the damage of PSII in the vtc2-1 mutant under high light. The results indicate that ascorbate plays a critical role in maintaining normal photosynthetic function in plants under high-light stress., L.-D. Zeng, M. Li, W. S. Chow, C.-L. Peng., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30575. Susceptibility of Chironomus plumosus larvae (Diptera: Chironomidae) to entomopathogenic nematodes (Rhabditida: Steinernematidae and Heterorhabditidae): Potential for control
- Creator:
- Edmunds, Cassandra V., Wilding, Craig S., and Rae, Robbie
- Type:
- article, model:article, and TEXT
- Subject:
- Diptera, Chironomidae, Chironomus plumosus, Rhabditida, Steinernematidae, Steinernema, Heterorhabditidae, Heterorhabditis, biocontrol, chironomids, entomopathogenic nematodes, and EPNs
- Language:
- English
- Description:
- Chironomidae, or non-biting midges, are found worldwide in a wide variety of aquatic habitats. During periods of mass adult eclosion they can become a nuisance and health hazard. Current control methods target the aquatic larval stage and include the use of insect growth regulators or insecticides, which may be prohibited in certain environments or affect non-target organisms. The aim of this study was to investigate whether entomopathogenic nematodes (EPNs) of the families Steinernematidae and Heterorhabditidae, currently employed for control of terrestrial crop pests, could be used as a viable biocontrol for the aquatic larval stages of the Chrionomidae, offering an alternative to current chemical methods. We demonstrate that Steinernema feltiae (Filipjev, 1934), Steinernema carpocapsae (Weiser, 1955), Steinernema kraussei (Steiner, 1923) and Heterorhabditis bacteriophora (Poinar, 1975) are able to survive in water up to 96 h and are able to parasitize and kill Chironomus plumosus (Linnaeus, 1758) larvae, with mortality observed after just 24 h exposure and with < 20% survival after 4 days. We also show that following application to the water column, EPNs sink to the bottom of the lentic water body and can remain alive for more than 96 h. Taken together, we believe that several EPN species could be developed as a valid form of biocontrol for Chironomidae.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30576. Susceptibility of green leaves and green flower petals of CAM orchid Dendrobium cv. Burana Jade to high irradiance under natural tropical conditions
- Creator:
- He, J. and Teo, L. C. D.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- CAM acidity, chlorophyll, electron transport rate, fluorescence induction, photosynthetic O2 evolution, photosynthetic photon flux density, and quenching
- Language:
- Multiple languages
- Description:
- Photosynthetic rates of green leaves (GL) and green flower petals (GFP) of the CAM plant Dendrobium cv. Burana Jade and their sensitivities to different growth irradiances were studied in shade-grown plants over a period of 4 weeks. Maximal photosynthetic O2 evolution rates and CAM acidities [dawn/dusk fluctuations in titratable acidity] were higher in leaves exposed to intermediate sunlight [a maximal photosynthetic photon flux density (PPFD) of 500-600 µmol m-2 s-1] than in leaves grown under full sunlight (a maximal PPFD of 1 000-1 200 µmol m-2 s-1) and shade (a maximal PPFD of 200-250 µmol m-2 s-1). However, these two parameters of GFP were highest in plants grown under the shade and lowest in full sun-grown plants. Both GL and GFP of plants exposed to full sunlight had lower predawn Fv/Fm [dark adapted ratio of variable to maximal fluorescence (the maximal photosystem 2 yield without actinic irradiation)] than those of shade-grown plants. When exposed to intermediate sunlight, however, there were no significant changes in predawn Fv/Fm in GL whereas a significant decrease in predawn Fv/Fm was found in GFP of the same plant. GFP exposed to full sunlight exhibited a greater decrease in predawn Fv/Fm compared to those exposed to intermediate sunlight. The patterns of changes in total chlorophyll (Chl) content of GL and GFP were similar to those of Fv/Fm. Although midday Fv/Fm fluctuated with prevailing irradiance, changes of midday Fv/Fm after exposure to different growth irradiances were similar to those of predawn Fv/Fm in both GL and GFP. The decreases in predawn and midday Fv/Fm were much more pronounced in GFP than in GL under full sunlight, indicating greater sensitivity in GFP to high irradiance (HI). In the laboratory, electron transport rate and photochemical and non-photochemical quenching of Chl fluorescence were also determined under different irradiances. All results indicated that GFP are more susceptible to HI than GL. Although the GFP of Dendrobium cv. Burana Jade require a lower amount of radiant energy for photosynthesis and this plant is usually grown in the shade, is not necessarily a shade plant. and J. He, L. C. D. Teo
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30577. Susceptibility of IFN-γ or IL-12 knock-out and SCID mice to infection with two microsporidian species, Encephalitozoon cuniculi and E. intestinalis
- Creator:
- Salát, Jiří, Sak, Bohumil, Le, Thuy, and Kopecký, Jan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Microsporidia, Encephalitozoon intestinalis, Encephalitozoon cuniculi, IFN-γ knock-out, IL-12 knock-out, and SCID mice
- Language:
- English
- Description:
- Susceptibility of three strains of immunodeficient mice to two related microsporidian species Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923 and Encephalitozoon intestinalis (Cali, Kotler et Orenstein, 1993) was compared. While both, severe combined immunodeficient (SCID) and interferon-gamma knock-out (IFN-γ KO) mice, succumbed to either intraperitoneal (i.p.) or peroral (p.o.) (natural) infection with both parasites, only i.p. infection with E. cuniculi killed interleukin-12 knock-out (IL-12 KO) mice. IFN-γ KO mice died earlier than SCID mice. Adoptive transfer of naive splenocytes from IFN-γ KO mice did not protect the SCID mice from a lethal infection with either of the Encephalitozoon species. However, reconstituted mice survived significantly longer (P<0.05), thus indicating the role of IFN-γ produced by host NK cells in the development of mechanisms of anti-microsporidial protective immunity. Non-lethal outcome of the infection always correlated with the increase in CD8+ T lymphocyte subpopulation. Both E. intestinalis-infected IFN-γ KO and IL-12 KO mice produced comparable levels of specific antibodies, suggesting that antibodies did not protect IFN-γ KO mice from lethal infection.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30578. Susceptibility to ischemia-induced arrhythmias and the effect of preconditioning in the diabetic rat heart
- Creator:
- Ravingerová, T., Štetka, R., Dezider Pancza, Oľga Uličná, Atila Ziegelhöffer, and Ján Styk
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, experimental diabetes, myocardial ischemia, preconditioning, arrhythmias, rat heart, 14, and 612
- Language:
- English
- Description:
- Diabetic heart is suggested to exhibit either increased or decreased resistance to ischemic injury. Ischemic preconditioning suppresses arrhythmias in the normal heart, whereas relatively little is known about its effects in the diseased myocardium. Our objective was to investigate whether development of diabetes mellitus modifies the susceptibility to ischemia-induced arrhythmias and affects preconditioning in the rat heart. Following 1 and 9 weeks of streptozotocin-induced (45 mg/kg, i.v.) diabetes, the hearts were Langendorff-perfused at constant pressure of 70 mm Hg and subjected to test ischemia induced by 30 min occlusion of the left anterior descending (LAD) coronary artery. Preconditioning consisted of one cycle of 5 min ischemia and 10 min reperfusion, prior to test ischemia. Susceptibility to ischemia-induced arrhythmias was lower in 1-week diabetics: only 42 % of diabetic hearts exhibited ventricular tachycardia (VT) and 16 % had short episodes of ventricular fibrillation (VF) as compared to VT 100 % and VF 70 % (including sustained VF 36 %) in the non-diabetics (P<0.05). Development of the disease was associated with an increased incidence of VT (VT 92 %, not significantly different from non-diabetics) and longer total duration of VT and VF at 9-weeks, as compared to 1-week diabetics. Preconditioning effectively suppressed arrhythmias in the normal hearts (VT 33 %, VF 0 %). However, it did not provide any additional antiarrhythmic protection in the acute diabetes. On the other hand, in the preconditioned 9-weeks diabetic hearts, the incidence of arrhythmias tended to decrease (VT 50 %, transient VF 10 %) and their severity was reduced. Diabetic rat hearts are thus less susceptible to ischemia-induced arrhythmias in the acute phase of the disease. Development of diabetes attenuates increased ischemic tolerance, however, diabetic hearts in the chronic phase can benefit more from ischem preconditioning, due to its persisting influence., T. Ravingerová, R. Štetka, D. Pancza, O. Uličná, A. Ziegelhöffer, J. Styk., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30579. Suspended particulate matter concentrations retrieved from self-calibrated multispectral satellite imagery
- Creator:
- Onderka, Milan, Rodný, Marek, and Velísková, Yvetta
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- self-calibration, suspended sediments, SPM, saturation, optimization, samokalibrácia, suspendované sedimenty, saturácia, and optimalizácia
- Language:
- Slovak
- Description:
- Inland waters are known to be laden with high levels of suspended particulate matter (SPM). Remotely sensed data have been shown to provide a true synoptic view of SPM over vast areas. However, as to date, there is no universal technique that would be capable of retrieving SPM concentrations without a complete reliance on time-consuming and costly ground measurements or a priori knowledge of inherent optical properties of water-borne constituents. The goal of this paper is to present a novel approach making use of the synergy found between the reflectance in the visual domain (~ 400-700 nm) with the near-infrared portion of the spectrum (~ 700-900 nm). The paper begins with a brief discourse of how the shape and spectral dependence of reflectance is determined by high concentrations of SPM. A modeled example is presented to mimic real-world conditions in fluvial systems, with specific absorption and scattering coefficients of the virtual optically active constituents taken from the literature. Using an optical model, we show that in the visual spectral domain (~ 400-700 nm) the water-leaving radiance responds to increasing SPM (0-100 g m-3) in a non-linear manner. Contrarily to the visual spectra, reflectance in the near infrared domain (~ 700-900 nm) appears to be almost linearly related to a broad range of SPM concentrations. To reduce the number of parameters, the reflectance function (optical model) was approximated with a previously experimentally verified exponential equation (Schiebe et al., 1992: Remote sensing of suspended sediments: the Lake Chicot, Arkansas project, Int. J. Remote Sensing, 13, 8, 1487-1509). The SPM term in Schiebe’s equation was expressed as a linear function of top-of-atmosphere reflectance. This made it possible to calibrate the reflectance in the visual domain by reflectance values from the near-IR portion of the spectrum. The possibility to retrieve SPM concentrations from only remote sensing data without any auxiliary ground mea-surements is tested on a Landsat ETM + scene acquired over a reservoir with moderately turbid water with SPM concentrations between 15-70 g m-3. The retrieved concentrations (on average) differ from in-situ measurement by ~ 10.5 g m-3. and Cieľom príspevku je prezentovať alternatívne spracovanie satelitných snímok na odhad koncentrácie suspendovaných sedimentov vo vodných útvaroch. Prvá časť článku sa venuje teórii a fyzikálnej podstate reflektancie a vplyvu prirodzene sa vyskytujúcich opticky aktívnych prvkov vo vode (suspendované sedimenty, pigmenty a rozpustené látky) na reflektanciu snímanú prostriedkami diaľkového prieskumu Zeme. Na modelovom príklade sme ukázali, že so zvyšovaním koncentrácie suspendovaných látok dochádza k saturácii signálu reflektancie.V druhej časti príspevku sme opísali spôsob využitia nelineárnosti vzťahu medzi reflektanciu vo viditeľnej časti (~ 400-700), a kvázi-linearitov v infračervenej časti (~ 700-900 nm) elektromegnetického spektra a koncentrácie suspendovaných sedimentov. Optimalizáciou tohto nelineárneho vzťahu sme odhadli koncentrácie suspendovaných sedimentov pre zdrž Hrušov pri Bratislave s RMSE 10.5 g m-3.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30580. Suspension hypokinesia in rats: effects of the time of day on metabolic and hormonal changes
- Creator:
- Ahlers, I., Ahlersová, E., Noskovič, P., Toth, G., Raček, Ĺ., Šmajda, B., and Smolnická, J.
- Type:
- article, model:article, and TEXT
- Subject:
- suspension hypokinesia, rats, metabolism, and day-time effects
- Language:
- English
- Description:
- Suspension hypokinesia is a new model which can simulate some effects of microgravity on the organism of laboratory animals. Two groups of male SPF-bred Wistar rats were suspended for 24 h. In the first group hypokinesia began in the morning (M) (1 h after light onset, 0800 h), whereas the other group was subjected to this treatment from the evening (E) (1 h after dark onset, 2000 h). In the serum, there was a statistically significant increase in non-esterified fatty acids, triacylglycerols (TG) and glucose and a decrease in triiodothyronine concentration in the M group, while only a significant increase in phospholipids (PL) was found in the E group. The serum corticosterone level was increased in both groups, more markedly in the M group. There was an increase in TG and PL in the liver in M rats. In the bone marrow (femur), an increase of triglycerols in E rats and an increase of phospholipids in M rats were found. The concentration of glycogen in the heart muscle, m. quadriceps femoris and m. soleus rose in the M group only. The changes in the analyzed parameters predominate in the rats subjected to hypokinesia in the morning period. This fact confirmed the hypothesis about a higher sensitivity of rats to the stressor acting in the period of inactivity.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public