227 research outputs found

    Dynamics of multiple sexual signals in relation to climatic conditions

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    Question: Can trait-specific phenotypic plasticity in response to annual environmental variation lead to changes in the strength of sexual selection through the relative expression of sexual ornaments at the population level? Data description: We recorded breeding dates and the sizes of white forehead and wing patches of male collared flycatchers (Ficedula albicollis) from 1998 to 2005 in a nestboxbreeding population in the Pilis Mountains, Hungary. As environmental predictors, we used the North Atlantic Oscillation (NAO) index and local weather data, classified as direct or indirect effects relative to the moult of the given ornament. Search method: First, we used general linear mixed models to assess environmental effects on the within-individual changes and absolute yearly sizes of forehead and wing patches. We then used similar models to determine whether the relative sizes of the two plumage traits at the population level varied among years. Finally, we used multiple regressions to establish if the relative yearly expression of an ornament affected standardized sexual selection gradients on this ornament in the given year. Conclusions: Within-individual changes in forehead and wing patch size were predicted by the climate of their moulting season (winter and summer, respectively). There was also an indirect effect of previous winter climate on changes in wing patch size. Environmental effects on the absolute expression of ornaments at the population level followed the within-individual patterns. The relative population-level expression of forehead and wing patches fluctuated significantly among years. Sexual selection on a given ornament increased with its relative expression in that year

    Fajgazdag szƑlƑsorköz-takarĂłnövĂ©nyzet magkeverĂ©kek vizsgĂĄlata Ă©s elƑzetes eredmĂ©nyei magyarorszĂĄgi szƑlĆ‘ĂŒltetvĂ©nyekben

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    Az utĂłbbi Ă©vtizedekben, a kertĂ©szeti kultĂșrĂĄkban is gyakran kerĂŒlnek elƑtĂ©rbe alternatĂ­v tĂĄjĂĄpolĂĄsi mĂłdszerek, mint pĂ©ldĂĄul a talajtakarĂĄs, vagy a takarĂłnövĂ©nyes talajĂĄpolĂĄs. Az ökolĂłgiai gazdĂĄlkodĂĄsban kĂŒlönöskĂ©ppen fontos szerepet jĂĄtszik a talaj termĂ©kenysĂ©gĂ©nek megƑrzĂ©se, a gazdag talajĂ©let fenntartĂĄsa, de ĂĄltalĂĄnossĂĄgban is megfigyelhetƑ bizonyos fokĂș szemlĂ©letvĂĄltĂĄs, miszerint a talajt nem pusztĂĄn termesztƑ közegnek kell tekinteni, hanem a termĂ©szet Ă©lettel teli rĂ©szĂ©nek, amelynek megĂłvĂĄsa, diverzitĂĄsĂĄnak, Ă©lƑvilĂĄgĂĄnak fenntartĂĄsa kertĂ©szti kultĂșrĂĄk mƱvelĂ©se mellett is lehetsĂ©ges, sƑt, kĂ­vĂĄnatos. A szƑlƑtermesztĂ©si ĂĄgazat esetĂ©n a talaj ĂĄpolĂĄsa, mint Ă©rtĂ©kmegƑrzĂ©si mĂłdszer, rendkĂ­vĂŒli jelentƑsĂ©ggel bĂ­r

    Analysis of Public Transport Performance in Budapest, Hungary

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    In 2001 the European Commission defined the main rules of the expected changes of modal split in the White paper. Modal split is also a crucial question in urban areas, where transport has the greatest effects on living standards and environment. Due to the caused pollution, noise, health effects every stakeholder tries to make urban public transport as efficient as it is possible. This is a theoretical investigation which aims to analyze the production function of Budapest Public Transport in Hungary. In this paper the transport data of Budapest were used to create a model in which the effects of different production factors can be estimated and the public transport performance can be forecasted

    KĂŒlönbözƑ tĂ­pusĂș gyepek makro- Ă©s mikroelem tartalmĂĄnak alakulĂĄsa a hasznosĂ­tĂĄsi gyakorisĂĄg fĂŒggvĂ©nyĂ©ben

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    HazĂĄnkban a juhok takarmĂĄnyozĂĄsa gyepre alapozott, vagyis a körĂŒlbelĂŒl 200 napos legeltetĂ©si idĂ©nyen kĂ­vĂŒli idƑszakban is zömĂ©ben a gyeprƑl betakarĂ­tott takarmĂĄnyt fogyasztjĂĄk az ĂĄllatok. A sok elƑny mellett vannak ĂĄllategĂ©szsĂ©gĂŒgyi vonatkozĂĄsai, esetleg kockĂĄzatai is a legelƑn valĂł tartĂĄsnak. KutatĂĄsunk fƑ cĂ©lkitƱzĂ©se volt, hogy megvizsgĂĄljuk kĂ©t eltĂ©rƑ vĂ­zellĂĄtottsĂĄgĂș (szĂĄraz Ă©s ĂŒde) terĂŒleten talĂĄlhatĂł gyeprƑl betakarĂ­tott takarmĂĄny makro- Ă©s mikroelem tartalmĂĄt. A vizsgĂĄlt alföldi elhelyezkedĂ©sƱ, szĂĄraz fekvĂ©sƱ gyep ĂĄsvĂĄnyianyag-tartalma hat elem esetĂ©ben (P, Mg, Cu, Zn, Mn, Na) nem Ă©rte el a juhok szĂĄmĂĄra szĂŒksĂ©ges mennyisĂ©get, több esetben mĂ©g a kĂ­vĂĄnt mennyisĂ©g felĂ©t sem szolgĂĄltatta a takarmĂĄny. Az ĂŒde fekvĂ©sƱ, mendei gyep a rĂ©z Ă©s a cink kivĂ©telĂ©vel a juhok egĂ©szsĂ©ges tĂĄplĂĄlĂĄsĂĄhoz elegendƑ ĂĄsvĂĄnyianyagot tartalmazott

    Szabad- és micellåban kötött rövid poli(etilén-oxidok) konformåciójånak és transzporttulajdonsågainak vizsgålata = Short-chain poly(ethylene oxides) free and bound to micelles: study of conformation and transport properties

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    A kutatĂĄsaink sorĂĄn sokoldalĂș vizsgĂĄlat alĂĄ vettĂŒk az etoxilĂĄlt nonil-fenolok nagy gyakorlati jelentƑsĂ©ggel rendel- kezƑ anyagcsoportjĂĄt, amelyrƑl az irodalomban nagyon kevĂ©s közlemĂ©ny jelent meg, Ă©s amelyet modern kĂ­sĂ©rleti technikĂĄkkal nem vizsgĂĄltak, vagy ha vizsgĂĄltak, az eredmĂ©nyeket nem közöltĂ©k. Az eltĂ©rƑ mĂłdszerekkel kapott eredmĂ©nyek egymĂĄst erƑsĂ­tve adnak kĂ©pet az ENP micellĂĄk struktĂșrĂĄjĂĄrĂłl Ă©s diffĂșziĂłs tulajdonsĂĄgairĂłl. - Egy rigorĂłzus modell - közelĂ­tƑ - alkalmazĂĄsĂĄval Ă©rtelmeztĂŒk az etoxilĂĄlt nonil-fenol homolĂłgok keverĂ©keibƑl kĂ©szĂ­tett vizes oldatok sƱrƱsĂ©gĂ©t az oldatkoncentrĂĄciĂł Ă©s a keverĂ©k ĂĄtlagos etoxiszĂĄmĂĄnak fĂŒggvĂ©nyĂ©ben. - Dinamikus Ă©s sztatikus fĂ©nyszĂłrĂĄssal meghatĂĄroztuk a micellĂĄk diffĂșziĂłs ĂĄllandĂłjĂĄt, hidrodinamikai sugarĂĄt, ĂĄtla- gos aggregĂĄciĂłs szĂĄmĂĄt, mĂĄsodik viriĂĄl-egyĂŒtthatĂłjĂĄt. Ă©s a sĂșrlĂłdĂĄsi egyĂŒtthatĂł koncentrĂĄciĂłfĂŒggĂ©sĂ©t, amelybƑl sikeresen megjĂłsoltuk, hogy melyik etoxiszĂĄmnĂĄl vĂĄrhatĂł a viszkozitĂĄsban minimum. - Megmutattuk, hogy vĂ©gtelen hĂ­gĂ­tĂĄsban a fĂ©nyszĂłrĂĄs Ă©s NMR ekvivalens diffĂșziĂłs egyĂŒtthatĂłkhoz vezet. - MolekulĂĄris modellt kĂ©szĂ­tettĂŒnk a micellĂĄris oldatokbĂłl szĂĄrmazĂł kisszögƱ szĂłrĂĄsi spektrumok leĂ­rĂĄsĂĄra. A rönt- genspektrumok kiĂ©rtĂ©kelĂ©se a fĂ©nyszĂłrĂĄssal azonos aggregĂĄciĂłs szĂĄmokat eredmĂ©nyezett, az etoxi-szĂĄmok radi- ĂĄlis eloszlĂĄsĂĄhoz jĂłl illeszkedtek a dinamikus fĂ©nyszĂłrĂĄsbĂłl kapott hidrodinamikai sugarak. | Ethoxylated nonyl phenols have been studied by various experimental methods. The reason for the study was that very small number of publications were found in the literature and that the modern experimental methods were not applied at all. The results of the present study from different experimental techniques support one another providing a more reliable picture of the structure and diffusion of ENP micelles. -Solution density of mixtures formed by homologues of ethoxylated nonyl phenols was described in terms of solute concentratin and mean ethoxy number by the approximate version of a rigorous model. -Diffusion coefficient, hydrodynamic radius, aggregation number, second virial coefficiet and the concentration dependence of the friction coefficient of micelles were determined by dynamic and static light scattering. Based on the friction coefficient, the minimum location of the viscosity of the materials was succesfully predicted vs. the mean ethoxy number. -It was shown that NMR and dynamic light scattering lead to equivalent diffusion coefficients in infinite dilution -Molecular model was elaborated for describing small angle scattering patterns from micellar solutions. Evalua- tion of X-ray patterns resulted in aggregation numbers in good agreement with static light scattering results. Hydrodynamic radii from dynamic light scattering properly fit the radial distributions of the ethoxy groups
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