Exploring decision-making strategies in the Iowa gambling task and rat gambling task

Decision-making requires that individuals perceive the probabilities and risks associated with different options. Experimental human and animal laboratory testing provide complimentary insights on the psychobiological underpinnings of decision-making. The Iowa gambling task (IGT) is a widely used instrument that assesses decision-making under uncertainty and risk. In the task participants are faced with a choice conflict between cards with varying monetary reinforcer/loss contingencies. The rat gambling task (rGT) is a pre-clinical version using palatable reinforcers as wins and timeouts mimicking losses. However, interspecies studies elaborating on human and rat behavior in these tasks are lacking. This study explores decision-making strategies among young adults (N = 270) performing a computerized version of the IGT, and adult outbred male Lister Hooded rats (N = 72) performing the rGT. Both group and individual data were explored by normative scoring approaches and subgroup formations based on individual choices were investigated. Overall results showed that most humans and rats learned to favor the advantageous choices, but to a widely different extent. Human performance was characterized by both exploration and learning as the task progressed, while rats showed relatively consistent pronounced preferences for the advantageous choices throughout the task. Nevertheless, humans and rats showed similar variability in individual choice preferences during end performance. Procedural differences impacting on the performance in both tasks and their potential to study different aspects of decision-making are discussed. This is a first attempt to increase the understanding of similarities and differences regarding decision-making processes in the IGT and rGT from an explorative perspective

Investigation of the surface integrity of mechano-chemically finished powder metallurgy gears

Automotive gears are facing stringent requirements regarding weight and functional surfaces, especially in view of the electric powertrain. To achieve these demands, powder metallurgy gears need to be finished using grinding, and in certain cases, mechano-chemical treatments. With regards to the latter, five different triboconditioning strategies based on vibratory tub finishing and/or centrifugal barrel finishing were considered and their effects on the surface integrity and friction behavior were investigated. Triboconditioning improved the surface roughness after grinding and resulted in higher compressive residual stresses. Additionally, microscopic observations of the surface topography were carried out. The lowest friction coefficients were observed for triboconditioning with a doped material (tribofilm) on the finished surface

Measurement of the Tau Lepton Polarisation at LEP2

A first measurement of the average polarisation P_tau of tau leptons produced in e+e- annihilation at energies significantly above the Z resonance is presented. The polarisation is determined from the kinematic spectra of tau hadronic decays. The measured value P_tau = -0.164 +/- 0.125 is consistent with the Standard Model prediction for the mean LEP energy of 197 GeV.A first measurement of the average polarisation Pτ of tau leptons produced in e + e − annihilation at energies significantly above the Z resonance is presented. The polarisation is determined from the kinematic spectra of tau hadronic decays. The measured value Pτ=−0.164±0.125 is consistent with the Standard Model prediction for the mean LEP energy of 197 GeV.A first measurement of the average polarisation P_tau of tau leptons produced in e+e- annihilation at energies significantly above the Z resonance is presented. The polarisation is determined from the kinematic spectra of tau hadronic decays. The measured value P_tau = -0.164 +/- 0.125 is consistent with the Standard Model prediction for the mean LEP energy of 197 GeV

Gymnasieelevers uppfattningar om matematiska symboler

För denna uppsats har syftet varit att titta närmare på elevernas uppfattningar om matematiska symboler på gymnasiet. För att ta reda på elevernas uppfattningar om matematiska symboler har jag gjort en enkätundersökning. Av de svar jag fick ger det en antydan om att eleverna kan namnge och beskriva åtminstone en del av de matematiska symboler som de är förväntade att kunna. Eleverna visar en viss antydan av att ha lättare för att skriva om en matematisk textformulering till matematiska symboler än att skriva om matematiska symboler till matematisk text. De flesta av eleverna anser att de ser en matematisk symbol som någon form av bild och nästan alla anser sig lära en ny matematisk symbol på lektionstid där flertalet frågar läraren om de inte kan. Denna studie vänder sig främst till lärare inom matematik för de senare åren men även till övriga matematiklärare som vill få en inblick i hur elever kan förhålla sig till matematiska symboler

Evaluation of Different Concepts for Pressed and Sintered Connecting Rods

Connecting rod are found in most combustion engines and transmits thrust from the piston to the crankshaft. The connecting rod needs to withstand forces from the piston and inertia forces which results in axial tension, compression stresses and bending. Today the most common manufacturing techniques in automotive industry are drop-forging, die-casting and the Powder Metallurgy technique used is powder-forging. In this Master Thesis different connecting rod designs for a single press PM manufacturing process were created and evaluated as a part of Höganäs AB's Total Powder Metal Car project, TPMC. This paper will serve as a basis for future connecting rod projects at Höganäs AB when choosing a suitable connecting rod design. The main objective of this Master Thesis is to evaluate different designs in regards to the following: Buckling strength Fatigue life Manufacturing rating The study shows that there is evidence that a single pressed connecting rod is possible. No absolute answer of which design is the best is given in this paper since in depends on different parameters and application. For each parameter examined there are results presented and arguments for and against each design which can aid designers in future work. Suggestions of improvement on both the method and on the designs are presented in respect to the results. The improvements may potentially increase the fatigue life, buckling strength and improve manufacturability

Performance measurement within Swedish public transport

Bakgrund: Prestationsmätning är en viktig del av ekonomistyrning och mätningarna ser olika ut beroende på organisation. Inom offentlig verksamhet har intresset för prestationsmätning ökat i och med New Public Management-idéerna (NPM). NPM har bidragit till en ökad företagsekonomisk inriktning på offentlig styrning, där resurshushållning och effektivitet fått ett tydligare fokus. Prestationsmätning har tidigare främst förknippats med finansiella prestationer. Under 1980- och 90-talen ökade kritiken mot detta ensidigt finansiella intresse, företrädelsevis ur en företagskontext. Att även utföra icke-finansiell prestationsmätning, och att då ha en flerdimensionell styrning, framhölls allt oftare som ett sätt att få organisationer mer framgångsrika. En av de mest välkända styrmetoderna för detta synsätt är det balanserade styrkortet. Balanserade styrkort som flerdimensionell styrmetod är enligt vissa forskare lämpligt även för offentlig verksamhet. Andra forskare menar att offentlig verksamhet genom NPM och fokus på resurshushållning samt effektivitet i sig är endimensionellt. Kollektivtrafiken i Sverige tillhör den offentliga sektorn. Under senare år har kollektivtrafiken dragits med låg effektivitet samtidigt som branschen har som mål att fördubbla resandet. Hur väl balanserade är olika perspektiv inom kollektivtrafiken?   Syfte: Syftet med denna studie är att undersöka befintlig perspektivbalans av de mått som används bland svenska kollektivtrafikhuvudmän samt att kartlägga faktiska prioriteringar mellan olika mål och mått. Metod: Till denna studie har det använts kvantitativ metod med en deduktiv ansats, arbetsgången har varit parallell.  Empirisk data har insamlats genom enkätundersökning som skickats ut till respondenter hos samtliga trafikhuvudmän i landet. Slutsats: Inom kollektivtrafiken finns det en relativt god balans mellan olika perspektiv, både i organisationer som uttalat använder sig av balanserade styrkort och de som uppger att de inte gör det. Enkätstudien visar att bland de fem perspektiv som studien utgått från är kundperspektivet och utvecklingsperspektivet de som används mest aktivt inom kollektivtrafiken. Det finansiella perspektivet och effektivitetsperspektivet är något man arbetar mindre med. Några enskilda mått som framstår som mest frekvent använda är antal resenärer, kundnöjdhet och att hålla sig inom budget. Studiens resultat visar att man arbetar mer aktivt med prestationsmätning inom organisationer som använder balanserat styrkort samt att trafikdirektörer arbetar mer aktivt med prestationsmätning jämfört med andra funktioner.Context: Measuring Performance is an important part of management control, as well as the manner in which these performance measurements are implemented in different organizations. Interest in measuring performance in the public sector has grown with the introduction of New Public Management (NPM). NPM has contributed to a more business-like way of dealing with public management, focusing on efficiency and resource management. Previously, performance measurements were mainly associated with financial performance. During the 1980s and 1990s, criticism arose against what was perceived as being companies focusing solely on financial performance. Complementing non-financial performance measurements were seen as way of bringing more prosperity to organizations. One of the most well-known multi-dimensional management methods is the balanced scorecard. According to some researchers, balanced scorecards are also suitable for public sector management, due to their multiple dimensions. Other research indicates that the influence of NPM and the focus on efficiency and resource management in this sector is one dimensional. The public transport sector in Sweden is partly funded by public finance and hence part of the public sector. During the last decade, public transport has lacked efficiency, while at the same time having a goal of doubling the number of passengers using its services. How balanced are the different perspectives in the public transport in Sweden? Aim: The aim of this study is to investigate the balance between the different modes of performance measurement used within the Swedish public transport system. Secondly, this work aims to map the actual priorities of the different measurements used. Method: This study uses a quantitative method with a deductive approach; the work process has taken place in parallel. Empirical data has been collected by means of a web-based survey that has been sent out to respondents working in all the public transport authorities in Sweden. Conclusion: Within the Swedish public transport system, there is a relatively good balance between different perspectives; this pertains to both the organizations that use balanced scorecards and the non-users. This study shows that among the five researched viewpoints, the customer aspect and the development aspect are the aspects pursued most actively. The financial aspect and efficiency aim are pursued less actively. Single measurements that seem to be most actively used are the number of passengers, customer satisfaction and keeping within budget. The results also indicate that there is a more active work done with performance measurements within organizations, which use balanced scorecards and that traffic directors are using performance measurements more actively than other functions

Blood pressure screening in midlife aids in prediction of dementia later in life

Background: There is substantial evidence that midlife hypertension is a risk factor for late life dementia. Our aim was to investigate if even high blood pressure at a single timepoint in midlife can predict an increased risk for all-cause dementia, Alzheimer's disease (AD), or vascular dementia (VaD) later in life. Methods: The community-based study population comprised 30,102 dementia-free individuals from the Westmannia Cardiovascular Risk Factors Study. The participants were aged 40 or 50 years when the health examination took place in 1990-2000. Diagnose registers from both hospitals and primary healthcare centers were used to identify individuals who after inclusion to the study developed dementia.The association between midlife high blood pressure (defined as systolic blood pressure >140 and/or diastolic blood pressure >90 mmHg) at a single timepoint and dementia was adjusted for age, gender, body mass index (BMI), fasting blood glucose, education, smoking, and physical activity level. Multivariate binary cox regression analyses were used. Results: After a mean follow-up time of 24 years resulting in 662,244 person/years, 761 (2.5%) individuals had been diagnosed with dementia. Midlife high blood pressure at a single timepoint predicted allcause dementia (hazard ratio [HR]: 1.22, 95% confidence interval [CI]: 1.02-1.45) and VaD (HR: 2.10, 95% CI: 1.47-3.00) but not AD (HR: 1.06, 95% CI: 0.81-1.38). Conclusion: This study suggests that even midlife high blood pressure at a single timepoint predicts allcause dementia and more than doubles the risk for VaD later in life independently of established confounders. Even though there was no such association with AD, this strengthens the importance of midlife health examinations in order to identify individuals with hypertension and initiate treatment

Autonomic responses during Gambling: the Effect of Outcome Type and Sex in a large community sample of young adults

International audiencePsychological theories consider autonomic arousal to be a reinforcer for problem gambling. Structural characteristics such as near-misses, which are non-win events that come close to a real win, have been shown to elicit win-like responses while increasing motivation and gambling persistence. This study investigated the autonomic and subjective responses of young adults to different gambling outcomes. This study also investigated sex differences in autonomic and subjective responses to different gambling outcomes. Participants from Sweden (n = 270) performed a computerized slot machine task that produced wins, near-misses (before and after payline) and full-misses. Phasic measurements of heart rate (HR) and skin conductance responses (SCR) were recorded during gambling performance and ratings of perceived chance of winning, pleasure and motivation to play were collected following each gambling outcome. Autonomic responses differed across slot machine outcomes as indicated by HR and SCR. Compared with other gambling outcomes, near-misses elicited the largest HR accelerations, and they also elicited larger HR decelerations and SCRs relative to full-misses. Near-misses before and after payline elicited differential psychophysiological responses and subjective reports, suggesting different emotional processing of near-miss subtypes. Females showed increased SCRs and motivation following win outcomes compared with males. In conclusion, wins, near-misses and full-misses generate differential physiological and subjective responses among young adults. Autonomic responses to wins differed between male and female players, emphasizing the need to consider sex differences when investigating the role of autonomic arousal in gambling

Pulmonary tuberculosis patients with a vitamin D deficiency demonstrate low local expression of the antimicrobial peptide LL-37 but enhanced FoxP3+ regulatory T cells and IgG-secreting cells

AbstractControl of human tuberculosis (TB) requires induction and maintenance of both macrophage and T cell effector functions. We demonstrate that pulmonary TB patients with a vitamin D deficiency had significantly reduced local levels of the vitamin D-inducible antimicrobial peptide LL-37 in granulomatous lesions compared to distal parenchyma from the infected lung. Instead, TB lesions were abundant in CD3+ T cells and FoxP3+ regulatory T cells as well as IgG-secreting CD20+ B cells, particularly in sputum-smear positive patients with cavitary TB. Mycobacteria-specific serum IgG titers were also elevated in patients with active TB. An up-regulation of the B cell stimulatory cytokine IL-21 correlated with mRNA expression of CD20, total IgG and also IL-10 in the TB lesions. Altogether, vitamin D-deficient TB patients expressed a weak antimicrobial response but an IL-21 associated expansion of IgG-secreting B cells combined with a rise in FoxP3+ regulatory T cells at the local site of infection

Exploring decision-making strategies in the Iowa gambling task and rat gambling task

Decision-making requires that individuals perceive the probabilities and risks associated with different options. Experimental human and animal laboratory testing provide complimentary insights on the psychobiological underpinnings of decision-making. The Iowa gambling task (IGT) is a widely used instrument that assesses decision-making under uncertainty and risk. In the task participants are faced with a choice conflict between cards with varying monetary reinforcer/loss contingencies. The rat gambling task (rGT) is a pre-clinical version using palatable reinforcers as wins and timeouts mimicking losses. However, interspecies studies elaborating on human and rat behavior in these tasks are lacking. This study explores decision-making strategies among young adults (N = 270) performing a computerized version of the IGT, and adult outbred male Lister Hooded rats (N = 72) performing the rGT. Both group and individual data were explored by normative scoring approaches and subgroup formations based on individual choices were investigated. Overall results showed that most humans and rats learned to favor the advantageous choices, but to a widely different extent. Human performance was characterized by both exploration and learning as the task progressed, while rats showed relatively consistent pronounced preferences for the advantageous choices throughout the task. Nevertheless, humans and rats showed similar variability in individual choice preferences during end performance. Procedural differences impacting on the performance in both tasks and their potential to study different aspects of decision-making are discussed. This is a first attempt to increase the understanding of similarities and differences regarding decision-making processes in the IGT and rGT from an explorative perspective.De två första författarna delar förstaförfattarskapetDe två sista författarna delar sistaförfattarskapet</p