Optimális éves viselkedési modellek: út a fiziológiától a populációkig? = Optimal annual routines: a path from physiology to populations?

A pályázat fő célja annak kiderítése volt, hogy a különböző állapotváltozók hogyan befolyásolják az optimális viselkedést, speciálisan a hogyan befolyásolják a fő életmenet események időzítését az éves cikluson belül. E cél elérése érdekében több modellt fejlesztettünk, és változatos terepi megfigyeléseket és aviáriumi kísérleteket folytattunk. Fő modelljeink azt mutatják, hogy az állapotváltozók (pl. tollminőség, energiatartalékok) jelentősen befolyásolhatják a vedlés és vándorlás időzítését, de a táplálékforrás időbeli eloszlása és szezonalitása is jelentős hatással lehet. Fő empirikus eredményeink szerint a táplálék minősége és a paraziták fertőzése jelentősen befolyásolhatja a tollminőséget. Egy komparatív vizsgálatban kimutattuk, hogy a vándorlás időzítését a különféle életmenet jellemzők jelentősen befolyásolják, de a szexuálisan szelektált jellegeknek nincs ilyen hatása. | The main aim of the project was to investigate how state variables effect optimal behaviour in general, and the optimal timing of major life history events over the annual cycle, in particular. To accomplish this aim we developed a couple of annual routine models and performed various field observations and aviary experiments. Our main models show that state variables (quality of feathers, energy reserves) can significantly influence the timing of optimal behaviour (moult, migration) but they also underline the importance of the temporal distribution and seasonality of food sources. Our main empirical results show that diet quality and parasite infection influence feather quality considerably. By a comparative study we found that life history traits (e.g. migration distance and diet) but not sexually selected traits influence the timing of migration

Location Determinants of Food Manufacturing Investment: Are Non-metropolitan Counties Competitive?

Food manufacturing site selection is determined by infrastructure, agglomeration, product and input markets, labor markets, and fiscal attributes of local communities. This article examines how these factors influence location decisions across the rural-urban continuum in the lower forty-eight states of the U.S. Negative binomial regression and spatial clustering methods are used to forecast new food processor location patterns at the county level, 2000-2004. Remote rural areas are at a comparative disadvantage with respect to attracting food processors, but non-metropolitan counties with economic links to urban core areas may be attractive investment sites for footloose, supply, and demand-oriented food manufacturers.firm location, food manufacturing, negative binomial regression, spatial clustering, Community/Rural/Urban Development, R1, R3,

Adolescents' and parents' views of Child and Adolescent Mental Health Services (CAMHS) in Ireland

Aim: To explore adolescents’ and parents’ experiences of CAMHS in relation to accessibility, approachability, and appropriateness. Methods: Using a descriptive qualitative design, a combination of focus group and single interviews were conducted with adolescents (n=15) and parents (n=32) from three mental health clinics. Data were transcribed verbatim and analysed using thematic analysis. Results: Accessing mental health services was a challenging experience due to knowledge deficit, lack of information and limited availability of specialist services. Participants desired more information, involvement in decision-making, single and shared consultations, flexible scheduling of appointments, continuity with clinicians, school support and parent support groups. Participants seem to be generally satisfied, however adolescents felt less involved in decision making than they would have liked. Frequent staff changes was problematic as it disrupted continuity of care and hindered the formation of a trusting relationship. Implications for practice: Parents and adolescents expressed similar views of the positive and negative aspects of mental health services. Their need for more information-sharing and involvement in decision-making underline the importance of collaborative practice. Clinician continuity contributed to trusting therapeutic relationships and was valued. These are key principles that with attention, could lead to quality service provision for adolescents and families

The energy flux into a fluidized granular medium at a vibrating wall

We study the power input of a vibrating wall into a fluidized granular medium, using event driven simulations of a model granular system. The system consists of inelastic hard disks contained between a stationary and a vibrating elastic wall, in the absence of gravity. Two scaling relations for the power input are found, both involving the pressure. The transition between the two occurs when waves generated at the moving wall can propagate across the system. Choosing an appropriate waveform for the vibrating wall removes one of these scalings and renders the second very simple.Comment: 5 pages, revtex, 7 postscript figure

Homogeneous cooling of rough, dissipative particles: Theory and simulations

We investigate freely cooling systems of rough spheres in two and three dimensions. Simulations using an event driven algorithm are compared with results of an approximate kinetic theory, based on the assumption of a generalized homogeneous cooling state. For short times $t$, translational and rotational energy are found to change linearly with $t$. For large times both energies decay like $t^{-2}$ with a ratio independent of time, but not corresponding to equipartition. Good agreement is found between theory and simulations, as long as no clustering instability is observed. System parameters, i.e. density, particle size, and particle mass can be absorbed in a rescaled time, so that the decay of translational and rotational energy is solely determined by normal restitution and surface roughness.Comment: 10 pages, 10 eps-figure

Cluster AgeS Experiment. CCD photometry of SX Phoenicis variables in the globular cluster M 55

We present CCD photometry of SX Phe variables in the field of the globular cluster M 55. We have discovered 27 variables, three of which are probable members of the Sagittarius dwarf galaxy. All of the SX Phe stars in M 55 lie in the blue straggler region of the cluster color-magnitude diagram. Using period ratio information we have identified the radial pulsation modes for one of the observed variables. Inspection of the period-luminosity distribution permits the probable identifications of the pulsation modes for most of the rest of the stars in the sample. We have determined the slope of the period-luminosity relation for SX Phe stars in M 55 pulsating in the fundamental mode. Using this relation and the HIPPARCOS data for SX Phe itself, we have estimated the apparent distance modulus to M 55 to be (m-M)_V=13.86 +- 0.25 mag.Comment: A&A accepted, 11 figure

Optimális vedlési stratégiák = Optimal moult strategies

A pályázat fő célja annak kiderítése volt, hogy a különböző állapotváltozók hogyan befolyásolják az optimális viselkedést, speciálisan a hogyan befolyásolják a fő életmenet események időzítését az éves cikluson belül. E cél elérése érdekében több modellt fejlesztettünk, és változatos terepi megfigyeléseket és aviáriumi kísérleteket folytattunk. Fő modelljeink azt mutatják, hogy az állapotváltozók (pl. tollminőség, energiatartalékok) jelentősen befolyásolhatják a vedlés és vándorlás időzítését, de a táplálékforrás időbeli eloszlása és szezonalitása is jelentős hatással lehet. Fő empirikus eredményeink szerint a táplálék minősége és a paraziták fertőzése jelentősen befolyásolhatja a tollminőséget. Egy komparatív vizsgálatban kimutattuk, hogy a vándorlás időzítését a különféle életmenet jellemzők jelentősen befolyásolják, de a szezuálisan szelektált jellegeknek nincs ilyen hatása. | The main aim of the project was to investigate how state variables effect optimal behaviour in general, and the optimal timing of major life history events over the annual cycle, in particular. To accomplish this aim we developed a couple of annual routine models and performed various field observations and aviary experiments. Our main models show that state variables (quality of feathers, energy reserves) can significantly influence the timing of optimal behaviour (moult, migration) but they also underline the importance of the temporal distribution and seasonality of food sources. Our main empirical results show that diet quality and parasite infection influence feather quality considerably. By a comparative study we found that life history traits (e.g. migration distance and diet) but not sexually selected traits influence the timing of migration

Inelastic Collapse of Three Particles

A system of three particles undergoing inelastic collisions in arbitrary spatial dimensions is studied with the aim of establishing the domain of ``inelastic collapse''---an infinite number of collisions which take place in a finite time. Analytic and simulation results show that for a sufficiently small restitution coefficient, $0\leq r<7-4\sqrt{3}\approx 0.072$, collapse can occur. In one dimension, such a collapse is stable against small perturbations within this entire range. In higher dimensions, the collapse can be stable against small variations of initial conditions, within a smaller $r$ range, $0\leq r<9-4\sqrt{5}\approx 0.056$.Comment: 6 pages, figures on request, accepted by PR

Energy flows in vibrated granular media

We study vibrated granular media, investigating each of the three components of the energy flow: particle-particle dissipation, energy input at the vibrating wall, and particle-wall dissipation. Energy dissipated by interparticle collisions is well estimated by existing theories when the granular material is dilute, and these theories are extended to include rotational kinetic energy. When the granular material is dense, the observed particle-particle dissipation rate decreases to as little as 2/5 of the theoretical prediction. We observe that the rate of energy input is the weight of the granular material times an average vibration velocity times a function of the ratio of particle to vibration velocity. `Particle-wall' dissipation has been neglected in all theories up to now, but can play an important role when the granular material is dilute. The ratio between gravitational potential energy and kinetic energy can vary by as much as a factor of 3. Previous simulations and experiments have shown that E ~ V^delta, with delta=2 for dilute granular material, and delta ~ 1.5 for dense granular material. We relate this change in exponent to the departure of particle-particle dissipation from its theoretical value.Comment: 19 pages revtex, 10 embedded eps figures, accepted by PR

Bifurcation Diagram for Compartmentalized Granular Gases

The bifurcation diagram for a vibro-fluidized granular gas in N connected compartments is constructed and discussed. At vigorous driving, the uniform distribution (in which the gas is equi-partitioned over the compartments) is stable. But when the driving intensity is decreased this uniform distribution becomes unstable and gives way to a clustered state. For the simplest case, N=2, this transition takes place via a pitchfork bifurcation but for all N>2 the transition involves saddle-node bifurcations. The associated hysteresis becomes more and more pronounced for growing N. In the bifurcation diagram, apart from the uniform and the one-peaked distributions, also a number of multi-peaked solutions occur. These are transient states. Their physical relevance is discussed in the context of a stability analysis.Comment: Phys. Rev. E, in press. Figure quality has been reduced in order to decrease file-siz