Ce travail présente la mesure de la section efficace différentielle du boson Z en impulsion transverse (ptz), dans le canal de désintégration electron-positron, avec le détecteur ATLAS au LHC. La mesure utilise 4.64 inverse fb de données de collisions proton-proton, prises en 2011 avec une énergie du centre de masse de 7 TeV. Le résultat est combiné avec une mesure indépendante faite dans le canal muon-antimuon. La mesure est faite jusqu'à ptz = 800 GeV, et a une incertitude typique de 0.5 % pour ptz < 60 GeV, atteignant jusqu'à 5 % vers la fin du spectre. La mesure est comparée avec modèles théoriques et prédictions des générateurs Monte Carlo.

This thesis is about the demography of the tunicate Styela clava, a species of some notoriety because of its invasiveness and impacts in many parts of the world. Species assemblages have continuously changed throughout evolutionary history, but the rate of today’s anthropogenically facilitated dispersal is unparalleled in history. Non-indigenous species (NIS) are now considered one of the most important risks to native biodiversity. NIS become invasive by becoming both widespread and locally dominant. This requires that a species becomes established, spreads locally, and increases in abundance. In the early stages of invasion, its demography and life history characteristics are of crucial importance. In New Zealand, Styela has established populations in several places, but none of these populations has yet reached the high densities found in other countries. In Lyttelton Port, where this study was located, Styela was first noticed in 2005. It therefore presented an ideal situation to study an invasive species in its early stages of establishment and provided a potentially good model for understanding how invasive species get local traction and spread from initial infestation points. Therefore, I set out to determine demographic features of Styela to understand the numbers game of population dynamics. This study used empirical data on growth rates, size-frequencies through time, and size and age to maturity to test several models, including von Bertalanffy, Logistic dose-response, Ricker and power models of individual growth. The most useful proved to be the von Bertalanffy model. Styela individuals shrink frequently, so average growth rates were often quite low, even though some individuals reached 160 mm or more in total length. Mortality was greatest in summer, presumably after reproduction, and lowest in winter. Fewer than 5% of individuals survived 12 months, and most or all of these died soon afterwards. Populations were, therefore, essentially annual. Recruitment was difficult to determine because of the cryptic nature of small juveniles. However, size-frequency, abundance and mortality data indicated that recruitment most likely occurred in early spring (late-October), and then again in late summer, with growth to maturity (at c. 50 mm total length) within < 5 months. Several manipulative experiments showed that Styela did not readily capitalise on provision of free space but the other non-native ascidian, Ciona intestinalis, rapidly recruited. Transplants of Styela were greatly affected by C. intestinalis, which overgrew them, similar to a localised replacement of Styela by Ciona seen overseas. Lefkovitch modelling was used to test whether Styela had an “Achilles heel” in its life history, whereby managed removal could impact future populations. This showed that under several scenarios intervention would most likely be ineffectual. Overall, this study showed that the original populations in Lyttelton Port are either static or in decline, somewhat contrary to original expectations. Nevertheless, it appears that these small populations may be acting as stepping stones for spread of this species outside of the port.

Stress and time pressure is more present in todays labor markets. In financial markets a securities broker is forced to take decisions on investments under high cognitive load and under extreme time pressure. The research of decision under risk gained new ground with the development of the prospect theory and gave us new insights to the decision making of men. Prospect theory has shown that people are risk seekers when dealing with loss decisions and risk avert when dealing with profit decisions. The value function are defined over gains and losses. Losses looms larger then gains. Although much research conducted on the decision making under risk no previous research have been done showing how time pressure affects decision at risk by using skin conductance. This paper aimed through a randomized experiment with 23 participants examine how time pressure affects individuals' decisions related to risk. Furthermore, it intends to analyze whether time pressure mediate a possible effect of stress by using skin conductance. The results show that there is an increase in risk aversion for gains. This risk aversion was also statistically significant at the 1% level when each participant's responses were used and almost at 5% level when the mean values from each participant was used. Upon loss a risk -seeking behavior could be noticed but it was not statistically significant at the 5 % level. Stress levels as measured by skin conductance showed that the time-pressed group showed signs of stress. However, no stress data was significant at the 5 % level. / Stress och tidspress är idag allt mer närvarande på arbetsmarknaden. På de finansiella marknaderna kan en värdepappersmäklare tvingas ta beslut om investeringar under hög kognitiv belastning och under en extrem tidspress. Forskningen av beslut under risk har genom prospect theory gett oss nya insikter om vilka beslut vi människor tar. Prospect theory har visat att människor är risksökande vid förlustfrågor och riskaversiva vid vinstfrågor. Prospect theorys värdefunktion är definierad över vinst och förlust. Förluster väger tyngre än vinster. Trots att mycket forskning genomförts på beslut vid risk har ingen tidigare forskning hur tidspress påverkar beslut vid risk med hjälp av hudkonduktans tidigare genomförts. Denna uppsats hade som mål att genom ett randomiserat experiment med 23 deltagare undersöka hur tidspress påverkar individers beslut kopplade till risk. Vidare är syftet att också analysera om upplevd stress medierar en eventuell effekt av tidspress genom att använda hudkonduktans. Resultatet visar att det finns en ökad riskaversion vid vinstfrågor. Denna riskaversion var även statistiskt säkerställd på 1% nivå när varje deltagares svar användes och nästan på 5% nivå då medelvärden från varje deltagare användes. Vid förlustfrågor fanns ett risksökande beteende men den var ej statistiskt säkerställd på 5% nivå. Stressnivåerna som uppmättes med hudkonduktans visade att den tidspressade gruppen blev stressade. Dock var inga stressdata signifikanta på 5% nivå.

The main goal of ultrarelativistic heavy-ion collisions is the study of the properties of the matter at very high temperatures and energy densities. Quantum chromodynamics (QCD) predicts in these conditions the existence of a new phase of the matter whose components are deconfined in a Quark-Gluon Plasma (QGP). Heavy quarks (charm e bottom) are produced in the first stages of the collisions, before to interact with the medium. Therefore, the measurement of the quarkonia (cc and bb mesons) is of particular interest for the study of the QGP: their dissociation mainly due to the colour screening is sensible to the initial temperature of the medium. Previous measurements at the SPS and RHIC allowed to understand some characteristics of the system produced, but they also opened many questions. With an energy 14 times higher than RHIC, the LHC (Large Hadron Collider) at CERN opened a new era for the study of the QGP properties. ALICE (A Large Ion Collider Experiment) is the LHC experiment fully dedicated to the study of the Quark-Gluon Plasma produced in Pb-Pb collisions at an energy of 2.76 TeV per nucleon. The experiment also participates to the proton-proton data taking in order to obtain the fundamental reference for the study of ion-ion and proton-ion collisions and for testing the predictions at very small Bjorken-x values of the perturbative QCD. Quarkonia, D and B mesons and light vector mesons are measured at forward rapidity by a Muon Spectrometer exploiting their (di)muonic decay. This detector is composed of a front absorber, a dipole magnet, five stations of tracking (Muon Tracking) and two stations of trigger (Muon Trigger). The work presented in this thesis has been carried out from 2011 to 2013 during the first period of data taking of ALICE. After a detailed introduction of the heavy-ion physics and a description of the experimental setup, the performance of the Muon Trigger in Pb-Pb collisions are shown. A particular attention is devoted to the stability of the detector during the time and to the trigger effectiveness. Moreover, the cluster size, corresponding to the number of adjacent strips hit by a particle, is studied as a function of different variables. The experimental results will be compared to simulations in order to obtain a good parametrization of this phenomenon. Finally, the Ç production in Pb-Pb collisions is carefully analysed and compared to that in pp collisions at the same energy. The results are then compared to the J/ψ measurements obtained by ALICE, to the CMS results and to some theoretical predictions.

Paper 1: Give More Tomorrow Many charities ask donors to commit to monthly contribution schemes. Monthly contributors give a fixed sum every month, which is automatically deducted from their bank account. These donors are the most profitable ones for a charity. On average, they give more than donors who contribute sporadically. They also facilitate the long-run financial planning of the charity, and they reduce the administrative and fundraising costs. What will influence a donor's decision to commit to a monthly contribution scheme? If the costs and benefits associated with contributing to a charity occur at different points in time, the answer will depend on the donor's inter-temporal preferences. More specifically, it will be of importance whether donors are time consistent or whether they exhibit present-biased preferences.  This paper designs and tests a fundraising strategy that allows for present-biased preferences among donors. The strategy, Give More Tomorrow, was implemented as a randomized field experiment in collaboration with a large charity. 1134 donors that make monthly contributions were randomly assigned to one of two treatment groups. In the first group, monthly donors were asked to increase their donation starting immediately. In the second group, monthly donors were asked to increase their donations starting two months later. Mean donations were 32 percent higher in the latter group, a highly significant difference. Donations conditional on giving were also significantly higher in the latter group. The effect of the GMT strategy is economically large and highly profitable to the charity. Paper 2: Crowding Out or Crowding In? The crowding-out hypothesis says that private givers, who are also taxpayers, will use their tax-financed donations as a substitute for their voluntary donations, thus reducing the net effectiveness of grants (Warr, 1982, 1983; Roberts, 1984; Bernheim, 1986; and Andreoni, 1988). While theory predicts a one-to-one relationship between government grants and private donations, econometric and experimental studies have found evidence of partial or no crowding out (see, e.g., Khanna et al., 1995; Payne, 1998; Khanna and Sandler, 2000; and Okten and Weisbrod, 2000). A recent contribution to this literature argues that government grants reduce the organizations' fundraising efforts, which may indirectly cause a decrease in private contributions (Andreoni and Payne, 2003). This paper employs a previously unexplored panel dataset to test whether government grants crowd out private donations to charitable organizations, controlling for changes in the organizations' fundraising behavior. The data covers all registered charitable organizations in Sweden between 1989 and 2003. We have a total of 361 organizations where the largest group is health related. The panel data allows us to control for unobserved organizational heterogeneity and time fixed effects. Furthermore, we use a 2SLS specification to control for possible endogeneity in government grants and fundraising expenditures. Complete crowding out can be strongly rejected. In the 2SLS regression, the estimated crowd-out is small and highly significant in the full sample, on average 5.0%. In the disaggregated sample, we cannot reject zero crowding out for any type of organization in the 2SLS regressions. Furthermore, we find strong evidence that organizations are net revenue maximizing, indicating that fundraising activities are efficient. Paper 3: Is Foreign Aid Paternalistic? (with Ola Granstrom and Felix Masiye) In this paper, we experimentally investigate whether donors are paternalistically altruistic when contributing to foreign aid. A paternalist may be defined as someone who advances other people's interests, such as life, health, or safety, at the expense of their liberty or autonomy. In economic theory, a donor is said to be paternalistically altruistic if he cares about a recipient's wellbeing, but does not fully respect the recipient's preferences (Pollak, 1988; Jones-Lee, 1991, 1992; Jacobsson et al., 2005). In a double-blind experiment, a subject chooses whether to make a monetary or a tied transfer (mosquito nets) to an anonymous household in Zambia. Recipients have revealed preferences for money, as their willingness to pay for mosquito nets is positive but below the market price. A monetary transfer will therefore preserve the household's preferences while a tied transfer is paternalistic. The mean donation of mosquito nets differs significantly from zero, thereby implying paternalistic preferences among donors. Paternalistic donors constitute 65 percent of the total sample, whereas purely altruistic donors constitute 15 percent. We conclude that health-focused paternalistic rather than purely altruistic preferences dominate the foreign-aid giving of individuals. Paper 4: Altruism without Borders? (with Ola Granstrom) Why do individuals contribute to foreign aid? Does the willingness to give increase the more we know about the recipients? Although there is some literature on the strategic interests of countries in providing foreign aid, (see, e.g., Alesina and Dollar, 2000) very little is yet known about which preferences guide the foreign-aid giving of individual donors. This paper experimentally tests altruism over borders. We design a cross-country dictator game where the degree of identification of the recipient is varied in four treatments: (1) anonymity, (2) photo, (3) information and (4) photo and information. In addition, questionnaire data on donor characteristics is gathered. The mean donation is 55%, which is considerably higher than in standard dictator games. In contrast to previous within-country experiments, we find no significant effect of identification on donations. Furthermore, we find that women donate significantly more than men (64 compared to 50 percent) and that those who state that aid is too large donate significantly less than those who state that aid is too small (24 compared to 67 percent). / Diss. Stockholm : Handelshögskolan, 2006 S. 5-7: Summary of Papers, S. 13-125: 4 papers

This study investigates two questions about anti-predator behaviour of the red-backed shrike. 1) Is the red-backed shrike able to assess the differing dangers represented by various types or species of predators? 2) How does the red-backed shrike recognize the predator? We found, that the red-backed shrike (Lanius collurio) adjusts its anti-predator behaviour by assessing the potential threat to themselves from different predator species and by assessing the chance of a successful attack. Further, we found that the presence of general raptor salient features is absolutely necessary for proper categorisation of the intruder as a predator, whereas the natural species-specific colouration in itself is an insufficient cue.

The best estimates of environmental productivity and their relationship to species diversity on different spatial scales have been studied in grassland communities in an observational study. The fertilization effect on height, growth rate, survival rate and changes in species composition has been studied on an oligotrophic wet meadow in a manipulative experiment.

(in English): In this thesis, I investigate preferences of humanities-oriented 3rd year students of grammar schools in their choice of university they would apply for. The theoretical part provides a summary and data for a content analysis of previous research, which I use to identify key features of universities, which may affect the choices made by students. In the methodological part, I introduce and define the conjoint analysis, which is a tool best suited for capturing the decision making process. The analysis shows that the most important factors are reputation and atmosphere. Other rather influential attributes include those proposed by other authors such as distance from home, location, peer influence and communication of the university with the prospective students. In contrast to findings from other countries though, the influence of the entry exams has been found only for students with excellent grammar school study results. This is directly contrary to the effect of this attribute in previous research. Another distinct feature of my research is the inclusion of the possibility to study abroad as an attribute, which has been completely ignored in previous studies of this type. In this case, it is the fourth most important attribute. There are tendencies which suggest that future research...

The aim of this graduation theses is to explore one of the theme of the contemporary educational reform in Czech republic what is development of creativeness at the basic school education. This question is outlined in general terms in the firs part of the theses and subsequently developed on the subject of physics education. Special emphasis is placed on the comparing of standard creativeness developing instruments and usage of computing technologies by computer supported education what is another essential item of current education. Significant part of this thesis deals with the software for the basic school physics education and its evaluation. The theses ends with the experiment with pupils of a basic school that should compare these two creativeness developing instruments mentioned above and give impetus to another research in this subject.

Made available in DSpace on 2018-06-27T19:13:11Z (GMT). No. of bitstreams: 2 Thiago Freire Sangoi.pdf: 12425983 bytes, checksum: ce220af41739cae819f7a796ad5c53ce (MD5) Thiago Freire Sangoi.pdf.jpg: 4082 bytes, checksum: 9304a756fd0d6a5fe599c850d8d6c0ce (MD5) Previous issue date: 2012-08-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente trabalho consiste na proposta de inserção da Integração Teoria/ Experimento como prática de aprendizagem nas escolas de Ensino Médio através da elaboração e aplicação de um módulo didático que irá englobar a parte experimental e a teórico-científica. Para atender a esse propósito, foi elaborado e aplicado um módulo didático que se adapta aos currículos escolares e às orientações sugeridas pelos PCN s (Parâmetros Curriculares Nacionais), e também, ao mesmo tempo, abordam tópicos de propriedades da Termofísica. O módulo didático faz a abordagem dos conteúdos referentes à termofísica, tratando desde os conhecimentos teóricos, envolvendo energia cinética, temperatura, calor e equilíbrio térmico, para que, com esse embasamento, seja possível abordar mais consistentemente os tópicos da dilatação e das trocas de energia sob a forma de calor. Este módulo didático foi elaborado para atender um público de 21 (vinte e um) alunos do segundo ano do Ensino Médio do Colégio Dom Alberto, da cidade de Santa Cruz do Sul, no Rio Grande do Sul. O material tem sua estrutura organizada em forma sequencial para que abranja, da melhor maneira, os tópicos envolvidos. Assim, tanto o professor, que irá aplicar o módulo concomitantemente com o experimento, quanto o aluno, que irá seguir a sequência aplicada pelo professor, terão uma assimilação significativa do assunto abordado. Tanto o desenvolvimento quanto a aplicação do módulo didático estão ancorados na aprendizagem com significado de David Ausubel, em que a informação deve interagir e ancorar-se nos conceitos relevantes já pré-existentes na estrutura cognitiva do aluno. A elaboração do material teve como estrutura básica uma problematização inicial, organização do conhecimento e aplicação do conhecimento, propostos nos três momentos pedagógicos de Delizoicov e Angotti. A avaliação dos novos conceitos adquiridos em relação aos já preexistentes foram analisado através de questionários aplicados antes e após a aplicação do experimento, etapas que denominamos pré e pós experimento. Dessa forma, foi com base nesses questionários aplicados e analisados que se tornou possível verificar vestígios satisfatórios no ensino e na aprendizagem significativa por parte dos alunos envolvidos. Durante a primeira fase da discussão, denominada pré experimento, observou-se, por meio do material impresso devolvido ao professor, que a maioria dos alunos, cerca de 60%, demonstraram conhecimentos superficiais. Desse montante, uma minoria de alunos, cerca de 10%, demonstrou conhecimentos mais amplos sobre o tema, e o mesmo foi obtido por meio de livros didáticos de séries anteriores, jornais, documentários e nos programas de televisão em geral. Na segunda fase, chamada de pós experimento, também por meio do mesmo material impresso aplicado, foi observado que, do montante de 60% dos que tinham conhecimentos superficiais, houve uma suba para 80%, uma vez que o montante daqueles alunos com os conhecimentos mais amplos também se elevou para 55%. Entretanto, uma minoria dos alunos, pode-se dizer que se enquadram naqueles que apresentaram respostas medíocres, e assim demonstram visivelmente que preferem outras áreas do conhecimento que não se vinculam as veias exatas, e para este trabalho podem ser desconsideradas, uma vez que o enfoque principal era de um levantamento e não motivacional.