Non-extensive Motivated Parton Fragmentation Functions

A new form of fragmentation function is presented here, motivated by earlier non-extensive studies of jet fragmentation. We parametrized our Tsallis-like function on pion spectra and compared it to the most common fragmentation function parametrizations. It is shown that the new form is in agreement with earlier parametrizations, furthermore, its scale evolution overlap better with the experimental data.Comment: 4 pages, 2 figures, Presented at Hot Quarks 2018. Submitted to MDPI Proceeding

Exercising control over memory consolidation

Exercise can improve human cognition. A mechanistic connection between exercise and cognition has been revealed in several recent studies. Exercise increases cortical excitability and this in turn leads to enhanced memory consolidation. Together these studies dovetail with our growing understanding of memory consolidation and how it is regulated through changes in motor cortical excitability

Jets in hot nuclear matter : Resumming multiple emissions in QCD

Under tung-ion-kollisjonar med høg energi smeltar protonar og nøytronar saman og dannar eit kvark-gluon-plasma. Modifiseringa av jeter, som forplantar seg gjennom det avgrensa mediet, har vorte grundig forska på ved CERN-LHC, og BNL-RHIC i kollisjonseksperiment. I løpet av det siste tiåret har man samla opp omfattande kunnskap om teorien om jet-modifikasjonar. Denne avhandlinga presenterer eit konsistent og toppmoderne perspektiv på jet-modifikasjonar basert på perturbasjons-QCD. Tatt i betraktning nylege framsteg mot ei meir nøyaktig forklaring av jeter i høgenergifysikk, vert jet-modifikasjonar i mediet gjennomgått ved å fokusera på deira perturbasjonsstruktur i alle orden og definere grannsemda til observerbare jet-strålar.In high-energy heavy-ion collisions, protons and neutrons melt and form the quark-gluon plasma. The modification of jets, propagating through this deconfined medium, has been extensively studied at the CERN-LHC, and the BNL-RHIC colliders experiments. Over the last decade, extensive knowledge has piled up in the theory of jet modification. This thesis presents a consistent and state-of-the-art perspective of jet modification based on perturbative QCD. Considering recent progress toward a more accurate description of jets in high-energy physics, jet modification in the medium is reviewed by focusing on their all-order perturbative structure and defining the accuracy of quenched jet observables.Doktorgradsavhandlin

Land use and land reform in former Central and East European countries

The importance of agriculture is decreasing all over the world. The aim of the paper is to compare the ownership structure and land use in some selected former Central and Eastern European countries. The property structure and land use is in dichotomy, the production is performed simultaneously on small-size farms which produce primarily for self-consumption. The importance of farm land leases is increasing. The present paper tries to identify the main differences and similarities in land ownership and property structure, the changes in the last fifteen years, what happened and whether the expectations had been met. Furthermore the paper compares the main regulations of land ownership and tenancy in different countries, explains land market protection, and the need of a real valuation system of land.property structure, land prices, land use, land use and ownership, Land Economics/Use,

Quenching effects in the cumulative jet spectrum

The steeply falling jet spectrum induces a bias on the medium modifications of jet observables in heavy-ion collisions. To explore this effect, we develop a novel analytic framework to study the quenched jet spectrum and its cumulative. We include many energy-loss-related effects, such as soft and hard medium induced emissions, broadening, elastic scattering, jet fragmentation, cone size dependence, and coherence effects. We show that different observables, based on the jet spectrum, are connected, e.g., the nuclear modification, spectrum shift, and the quantile procedure. We present the first predictions for the nuclear modification factor and the quantile procedure with cone size dependence. As a concrete example, we compare dijet and boson+jet events to unfold the spectrum bias effects, and improve quark-, and gluon-jet classification using arguments based on the cumulative. Besides pointing out its flexibility, finally, we apply our framework to other energy loss models such as the hybrid weak/strong-coupling approach.publishedVersio

Resolving the spacetime structure of jets with medium

Away from the strictly soft and collinear limit of QCD radiation the choice of evolution scale in a parton shower algorithm is ambiguous and several options have been implemented in existing Monte Carlo event generators for proton-proton collisions. However, the resulting space-time evolution could result in subtle differences depending on the particular choice. In this work we quantify measurable consequences of the choice of the evolution variable and show how the implications of such a choice propagates into jet quenching observables. We develop a parton shower algorithm for a general evolution variable, that includes as special cases the virtuality, angle, transverse momentum and formation time. We study the interplay between the shower history for different evolution variables and the phase space affected by parton energy loss. In particular, we implement effects of jet quenching in the dense limit and highlight the role of color coherence effects. We compare the results of the different ordering variables to existing Monte Carlo shower implementations on the parton level by analyzing primary Lund planes. Finally, we study the sensitivity of quenched jets to the choice of evolution variable by confronting our results for a certain key observable, such as the jet mass.Comment: 5 pages, 4 figures, 10th International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions (Hard Probes 2020

Short mindfulness‐based relaxation training has no effects on executive functions but may reduce baseline cortisol levels of boys in first grade:A pilot study

(1) Background: Executive functions are important for academic performance and school readiness. Children’s executive function skills are found to be improved by mindfulness-based interventions, and these programs are also effective in stress reduction. The aim of this study was to evaluate the feasibility and the effects of a short mindfulness-based relaxation training compared to a passive control condition right before school entry on executive function skills and cortisol levels. (2) Methods: The feasibility and the effects of the intervention before school entry were tested with 61 preschoolers. The final sample consisted of 51 participants (M(age) = 81.90 months, SD = 5.45; 41% male). Short-term memory, executive function skills and cortisol levels before and after the intervention were assessed. Additionally, cortisol levels were assessed one week and one month after school entry. (3) Results: There was a significant sex difference in the effects of the intervention on children’s cortisol levels (p = 0.026, η(2) = 0.134). The mindfulness-based relaxation training applied before school entry prevented a rise in boys’ cortisol levels one week after starting school. (4) Conclusion: A short mindfulness-based intervention before starting school could be effective in fostering physiological stress management in boys

Benefits of a mindfulness-based intervention upon school entry:A pilot study

Background: mindfulness meditation is effective at fostering the executive functioning of children, i.e., the skills that play important roles in academic performance and social–emotional wellbeing. One possible mechanism for such an effect might be that meditation practices can decrease stress, especially if someone is at a risk for elevated cortisol levels, for instance, due to a stressful life event, such as starting school. Participants and methods: the present pilot study tested the effects of a six-session mindfulness intervention applied right after school entry compared to a passive control group. In total 61 first graders participated (M(age) = 84.95 months, SD = 5.21) in this study from four classes of a primary school in Budapest. Repeated-measures ANOVA were performed to explore the effects on executive functioning skills and cortisol levels. Results: no effect was found on morning salivary cortisol levels, but the working memory capacities of girls significantly improved as a result of the intervention. Conclusions: a relatively short, story-based mindfulness intervention can improve the working memory capacities of first-graders; thus, it could potentially contribute to the academic performance and adaptation of children in schools