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17292. Walter Isaacon, Einstein - jeho život a vesmír
- Creator:
- Langer, Jiří
- Format:
- Type:
- model:article and TEXT
- Subject:
- fyzika, physics, 6, and 53
- Language:
- Czech
- Description:
- [Jiří Langer].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
17293. Warburg’s intuitions in light of postmodern challenges
- Creator:
- Szónyi, Gyórgy E.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
17294. 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:
- 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
17295. 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
17296. Water stress and abscisic acid treatments induce the CAM pathway in the epiphytic fern Vittaria lineata (L.) Smith
- Creator:
- Minardi, B. D., Voytena, A. P. L., Santos, M., and Randi, Á. M.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, pigmenty, photosynthesis, pigments, Brazílie, Brasil, chlorophyll fluorescence, malate, morphoanatomy, photosynthetic pathway, Vittaria lineata, 2, and 581
- Language:
- Multiple languages
- Description:
- Among various epiphytic ferns found in the Brazilian Atlantic Forest, we studied Vittaria lineata (L.) Smith (Polypodiopsida, Pteridaceae). Anatomical characterization of the leaf was carried out by light microscopy, fluorescence microscopy, and scanning electron microscopy. V. lineata possesses succulent leaves with two longitudinal furrows on the abaxial surface. We observed abundant stomata inside the furrows, glandular trichomes, paraphises, and sporangia. We examined malate concentrations in leaves, relative water content (RWC), photosynthetic pigments, and chlorophyll (Chl) a fluorescence in control, water-deficient, and abscisic acid (ABA)-treated plants. Plants subjected to drought stress (DS) and treated by exogenous ABA showed significant increase in the malate concentration, demonstrating nocturnal acidification. These findings suggest that V. lineata could change its mode of carbon fixation from C3 to the CAM pathway in response to drought. No significant changes in RWC were observed among treatments. Moreover, although plants subjected to stress treatments showed a significant decline in the contents of Chl a and b, the concentrations of carotenoids were stable. Photosynthetic parameters obtained from rapid light curves showed a significant decrease after DS and ABA treatments., B. D. Minardi, A. P. L. Voytena, M. Santos, Á. M. Randi., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
17297. Water-deficiency effects on single leaf gas exchange and on C4 pathway enzymes of maize genotypes with differing abiotic stress tolerance
- Creator:
- Sicher, Richard, Bunce, J., Barnaby, J., and Bailey, B.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, sucha, kukuřice, photosynthesis, C4 photosynthesis, drought, enzyme activities, gene expression, phosphoenolpyruvate carboxylase, maize, abiotic stress, 2, and 581
- Language:
- Multiple languages
- Description:
- Responses to drought were studied using two maize inbred lines (B76 and B106) and a commercial maize hybrid (Zea mays L. cv. Silver Queen) with differing resistance to abiotic stress. Maize seedlings were grown in pots in controlled environment chambers for 17 days and watering was withheld from one half the plants for an additional 11 days. On the final treatment date, leaf water potentials did not differ among genotypes and were -0.84 and -1.49 MPa in the water sufficient and insufficient treatments, respectively. Greater rates of CO2 assimilation were retained by the stress tolerant maize inbred line, B76, in comparison to the other two genotypes 11 days after watering was withheld. Rates of CO2 assimilation for all three genotypes were unaffected by decreasing the measurement O2 concentration from 21 to 2% (v/v). Activities of phosphoenolpyruvate carboxylase (PEPC), NADP-malic enzyme (NADP-ME), and NADP malate dehydrogenase were inhibited from 25 to 49% by the water deficiency treatment. Genotypic differences also were detected for the activities of NADP-ME and for PEPC. Changes of transcript abundance for the three C4 pathway enzymes also varied among watering treatments and genotypes. However, examples where transcripts decreased due to drought were associated with the two stress susceptible genotypes. The above results showed that enzymes in the C4 photosynthetic pathway were less inhibited by drought in stress tolerant compared to stress susceptible maize genotypes., R. Sicher, J. Bunce, J. Barnaby, B. Bailey., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
17298. Wavelet decomposition in the earth's gravity field investigation
- Creator:
- Bogusz, Janusz, Klos, Anna, and Kosek, Wieslaw
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, gravitace, zemětřesení, gravity, earthquake, GGP, wavelet decomposition, Earth’s gravity field changes, 7, and 551
- Language:
- English
- Description:
- This paper presents the results of the application of wavelet decomposition to processing data from the GGP sites (The Global Geodynamics Project). The GGP is an international project within which the Earth's gravity field changes are recorded with high accuracy at a number of stations worldwide using superconducting gravimeters. Data with a 5-second sampling interval from Wettzell and Bad Homburg were used for the research. The wavelet transform enables the investigation of the temporal changes of the oscillation amplitudes or the decomposition of the time series for the analysis of the required frequencies. The wavelet decomposition was performed using the regular orthogonal symmetric Meyer wavelet. The research concerned data from an earthquake period recorded at various locations and a quiet period when the gravimeters worked without any disturbances. The decomposition was followed by the Fast Fourier Transform for signal frequency components and then by correlation analyses of corresponding frequency components (for periods from 10 to 60 000 seconds) for all sensor combinations, for the quiet and the earthquake periods separately. Frequency components defining long term changes for all sensor combinations, as well as combinations between two sensors at the same site for the quiet days are characterised by high correlation coefficients. For the time of the earthquake, the Wettzell site data proved strong correlation for all frequency components, while the Bad Homburg site data showed an unexpected decrease of correlation for the majority of frequency components. The authors also showed that wavelet decomposition can be a good method of data interpolation, especially from the time of earthquakes. Moreover, it is a very useful tool for filtering the data and removing the noises., Janusz Bogusz, Anna Klos and Wieslaw Kosek., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
17299. Weak- and strong-type inequality for the cone-like maximal operator in variable Lebesgue spaces
- Creator:
- Szarvas, Kristóf and Weisz, Ferenc
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, Lebesgueovy prostory, nerovnosti (matematika), mathematics, Lebesgue spaces, inequalities (mathematics), variable Lebesgue space maximal operator γ-rectangle Besicovitch’s covering theorem weak-type inequality strong-type inequality, maximal operator, γ-rectangle, Besicovitch’s covering theorem, weak-type inequality, strong-type inequality, 13, and 51
- Language:
- English
- Description:
- The classical Hardy-Littlewood maximal operator is bounded not only on the classical Lebesgue spaces Lp(Rd) (in the case p > 1), but (in the case when 1/p(·) is log-Hölder continuous and p- = inf{p(x): x\in Rd > 1) on the variable Lebesgue spaces Lp(·)(Rd), too. Furthermore, the classical Hardy-Littlewood maximal operator is of weak-type (1, 1). In the present note we generalize Besicovitch’s covering theorem for the so-called γ-rectangles. We introduce a general maximal operator Msγδ, and with the help of generalized Φ-functions, the strong- and weak-type inequalities will be proved for this maximal operator. Namely, if the exponent function 1/p(·) is log-Hölder continuous and p- ≥ s, where 1 ≤ s ≤ ∞ is arbitrary (or p- ≥ s), then the maximal operator Msγδ is bounded on the space Lp(·)(Rd) (or the maximal operator is of weak-type (p(·), p(·)))., Kristóf Szarvas, Ferenc Weisz., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
17300. Weather-dependent fluctuations in the abundance of the oak processionary moth, Thaumetopoea processionea (Lepidoptera: Notodontidae)
- Creator:
- Csóka, György, Hirka, Anikó, Szöcs, Levente, Móricz, Norbert, Rasztovits, Ervin, and Pödör, Zoltán
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- motýli, dolování dat, butterflies, data mining, Lepidoptera, Notodontidae, Thaumetopoea processionea, light trap, population fluctuation, Moran-effect, drought, oak defoliator, CReMIT-analysis, 2, and 59
- Language:
- English
- Description:
- Population fluctuations of the well-known oak defoliator, the oak processionary moth (Thaumetopoea processionea L.), were studied using light trap data and basic meteorological parameters (monthly average temperatures, and precipitation) at three locations in Western Hungary over a period of 15 years (1988-2012). The fluctuations in the numbers caught by the three traps were strongly synchronized. One possible explanation for this synchrony may be similar weather at the three trapping locations. Cyclic Reverse Moving Interval Techniques (CReMIT) were used to define the period of time in a year that most strongly influences the catches. For this period, we defined a species specific aridity index for Thaumetopoea processionea (THAU-index). This index explains 54.8-68.9% of the variation in the yearly catches, which indicates that aridity, particularly in the May-July period was the major determinant of population fluctuations. Our results predict an increasing future risk of Oak Processionary Moth (OPM) outbreaks and further spread if the frequency of severe spring/summer droughts increases with global warming., György Csóka, Anikó Hirka, Levente Szöcs, Norbert Móricz, Ervin Rasztovits, Zoltán Pödör., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public