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3812. Burial-induced changes in the seed preferences of carabid beetles (Coleoptera: Carabidae)
- Creator:
- Saska, Pavel, Honěk, Alois, Foffová, Hana, and Martinková, Zdenka
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Carabidae, food preferences, granivory, seed consumption, seed burial, and weeds
- Language:
- English
- Description:
- Seeds of many species of plants may survive for a long time in the soil and germinate when brought to the surface, but whether they are subsequently eaten by seed predators is unknown. We examined the preferences of three species of carabids (Coleoptera: Carabidae) for 25 species of seeds and determined the difference in palatability between freshly dispersed and those buried for six years. The stability of their preferences was tested using a collection of seeds of different species, each of which was offered fresh or after being buried. Carabid beetles readily accepted previously buried seeds as food. In total, Pseudoophonus rufi pes and Amara littorea ate more fresh seeds than previously buried seeds, while the opposite was true for Harpalus affi nis. The seeds of some species were even more attractive to carabids after burial than in the fresh state. For all the species of carabids tested, the diet breadth was similar when the beetles were fed fresh or buried seeds, but the preferences for fresh and buried seed of particular species were correlated only in P. rufi pes and A. littorea. We measured the seed characteristics (mass and viability) likely to be associated with the loss of attractiveness to carabids during burial. The change in carabid consumption was not related to changes in any of these characteristics. This fi nding indicates that factors responsible for variation in seed acceptability are complex. This study provides the fi rst conclusive evidence that invertebrate seed predators will feed on seeds from seed banks, although they prefer fresh seeds.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3813. Burst activity and synaptic mechanisms in a hypothalamic network grown in culture
- Creator:
- Misgeld, U. and Swandulla, D.
- Type:
- article, model:article, and TEXT
- Subject:
- cultured hypothalamic neurones, burst activity, and synaptic mechanisms
- Language:
- English
- Description:
- In a cultured network of rat embryonic hypothalamic cells, synaptic interaction is through GABAA-receptors, that mediate inhibition by an increase in Cl' conductance, and AMPA-receptors, that mediate excitation by an increase in monovalent cationic conductance. Changes in the balance of inhibition and excitation towards a predominance of excitation lead to phasic synchronous activity of the cells. Synaptic interaction through these receptors is thus capable of modulating neurosecretion rapidly.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3814. Bus arrival time prediction based on PCA-GA-SVM
- Creator:
- Peng, Zixuan , Jiang, Yonglei , Yang, Xiaoli , Zhao, Zhigang , Zhang, Liu , and Wang, Yitian
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- bus arrival time prediction, Principal Component Analysis (PCA), Support Vector Machine (SVM), and Kalman filter
- Language:
- English
- Description:
- Considering the correlations of the input indexes and the deficiency of calibrating kernel function parameters when support vector machine (SVM) is applied, a forecasting method based on principal component analysis-genetic algorithm-support vector machine (PCA-GA-SVM) is proposed to improve the precision of bus arrival time prediction. And the No. 232 bus in Shenyang City of China is taken as an example. The traditional SVM and Kalman Filtering model and GA-SVM are also employed to make comparative analysis on the prediction rate, respectively. The result indicates that PCA-GA-SVM obtains more accurate prediction results of bus arrival time prediction.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3815. Bus Arrival Time Prediction using Support Vector Machine with Genetic Algorithm
- Creator:
- Yang, M., Chen, C., Wang, L., Yan, X., and Zhou , L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- bus arrived time, prediction, Support Vector Machine (SVM), and genetic algorithm (GA)
- Language:
- English
- Description:
- Accurate prediction of bus arrival time is of great significance to improve passenger satisfaction and bus attraction. This paper presents the prediction model of bus arrival time based on support vector machine with genetic algorithm (GA-SVM). The character of the time period, the length of road, the weather, the bus speed and the rate of road usage are adopted as input vectors in Support Vector Machine (SVM), and the genetic algorithm search algorithm is combined to find the best parameters. Finally, the data from Bus No.249 in Shenyang, china are used to check the model. The experimental results show that the forecasting model is superior to the traditional SVM model and the Artificial Neural Network (ANN) model in terms of the same data, and is of higher accuracy, which verified the feasibility of the model to predict the bus arrival time.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3816. But they're threatening cursing us! A study of the complaints and notices sent in by Czechoslovak citizens during Czechoslovakia's perestroika /
- Creator:
- Vilímek, Tomáš,
- Type:
- text and studie
- Subject:
- Dějiny Česka a Slovenska, stížnosti, oznámení, anonymy, společnost československá, vztahy stát-společnost, perestrojka, strany politické, KSČ, Československo 1969-1989, dějiny společnosti, and politické strany a hnutí, volby
- Language:
- English
- Rights:
- unknown
3817. Butterflies (Lepidoptera) highlight the ecological value of shrubland and grassland mosaics in Cypriot garrigue ecosystems
- Creator:
- Özden, Özge and Hodgson, David J.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Kypr, Cyprus, Butterflies, Lepidoptera, garrigue, habitat, conservation, 2, and 59
- Language:
- English
- Description:
- We used butterfly assemblages to evaluate the ecological value of habitat mosaics within garrigue ecosystems in Cyprus. To understand the importance of the local plant communities for Cypriot butterflies, five plots in each of two habitat types (grass-dominated or shrub-dominated) were surveyed weekly for a period of five months in order to assess the abundance, species richness and diversity of butterflies. A total of 810 butterflies of 16 species were recorded. Indices of butterfly diversity, calculated across the whole season, were similar between grassland and shrubland dominated mosaics. However, species richness of all butterflies was consistently higher in grassland dominated mosaics throughout the whole season. The peak abundance of all butterfly species occurred during mid-season (late April - early May), with similar numbers observed in both habitat types. However, a greater abundance was observed during early and late season in grassland patches. The abundance of endemic species (Maniola cypricola, Hipparchia cypriensis, Glaucopsyche paphos) peaked earlier in the season in shrubland patches, but was higher in grassland patches in late season. This difference in seasonal timing of endemic abundance was dominated by the seasonal dynamics of M. cypricola. These results suggest that, while garrigue is characterised by its shrub flora, management to maintain a mosaic of grassland and shrubland could act to maximise the abundance and richness of indicator species groups of conservation importance. and Özge Özden, David J. Hodgson.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3818. Butterfly diversity and biogeography on the Croatian karst mountain Biokovo: Vertical distribution and preference for altitude and aspect?
- Creator:
- Mihoci, Iva, Hršak, Vladimir, Kučinić, Mladen, Mičetić Stanković, Vlatka, Delić, Antun, and Tvrtković, Nikola
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Dinárský kras, Dinaric Karst, Lepidoptera, butterflies, aspect, altitude, indicators, 2, and 59
- Language:
- English
- Description:
- Geographic isolation, altitude, climate, landscape and habitat are significant predictors of butterfly diversity in mountain ecosystems. Their diversity and its dependence on altitude, aspect (compass bearing) and biogeographic characteristics of the butterflies were surveyed on the karst mountain Biokovo in southern Croatia. The results affirm that there is a high diversity of butterflies in the study area and the species composition and biogeographic elements are more dependent on altitude than aspect of the mountain. The present study indicates that climate, relief and habitat preferences strongly influence the biogeographic features of species and the relationship between species richness per site and altitude, aspect and the altitude-aspect interaction. and Iva Mihoci, Vladimir Hršak, Mladen Kučinić, Vlatka Mičetić Stanković, Antun Delić, Nikola Tvrtković.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3819. Butyrate enemas upregulate Muc genes expression but decrease adherent mucus thickness in mice colon
- Creator:
- Gaudier, E., Rival, M., Buisine, M.-P., Robineau, I., and Hoebler, Christine
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, tlusté střevo, myši, physiology, large intestine, mice, mucus, mucin, butyrate, 14, and 612
- Language:
- English
- Description:
- Colonic mucosal protection is provided by the mucus gel, mainly composed of mucins. Several factors can modulate the formation and the secretion of mucins, and among them butyrate, an end-product of carbohydrate fermen tation. However, the specific effect of butyrate on the various colonic mucins, and the consequences in terms of the mucus layer thickness are not known. Our aim was to determine whether butyrate modulates colonic MUC genes expression in vivo and whether this results in changes in mucus synthesis and mucus layer thickness. Mice received daily for 7 days rectal enemas of butyrate (100 mM) versus saline. We demonstrated that butyrate stimulated the gene expression of both secreted (Muc2) and membrane-linked (Muc1, Muc3, Muc4) mucins. Butyrate especially induced a 6-fold increase in Muc2 gene expression in proximal colon. However, butyrate enemas did not modify the number of epithelial cells containing the protein Muc2, and caused a 2-fold decrease in the thickness of adherent mucus layer. Further studies should help understanding whether this last phenomenon, i.e. the decrease in adherent mucus gel thickness, results in a diminished protective function or not., E. Gaudier ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3820. BV solutions of rate independent differential inclusions
- Creator:
- Krejčí, Pavel and Recupero, Vincenzo
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- diferenciální inkluze, obsluha zastavení, hodnotit nezávislost, and konvexní sada
- Language:
- English
- Description:
- We consider a class of evolution differential inclusions defining the so-called stop operator arising in elastoplasticity, ferromagnetism, and phase transitions. These differential inclusions depend on a constraint which is represented by a convex set that is called the characteristic set. For BV (bounded variation) data we compare different notions of BV solutions and study how the continuity properties of the solution operators are related to the characteristic set. In the finite-dimensional case we also give a geometric characterization of the cases when these kinds of solutions coincide for left continuous inputs.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public