The growing interest in savings on the financial markets implicates that the competition is expanding and managers of Swedish equity funds need to create shareholder value, independent of the macroeconomic situation. The Swedish financial market experienced a rapid rebound during the first quarter of 2019, following the plunge in the preceding quarter. This thesis utilizes multiple linear regression to analyze Swedish equity funds during the first quarter of 2019. The aim is to identify variables affecting fund performance in a market rebound in order to formulate a performance maximizing strategy. Based on the results of the performance influencing variables, the strategy is to underweight small cap stocks, overweight the energy and technology sector, underweight the communication services sector and staying neutral to overweighted in remaining sectors. Furthermore, the strategy proposes an overweighted exposure to North American stocks and an underweight to Western European stocks. The overexposure to North America should be larger in absolute value compared to the underexposure to Western Europe. The strategy is ambiguous since data from only one market rebound is analyzed. Therefore, the strategy is not significantly proven to be adaptable in any market rebound. The model analysis is based on modern macroeconomic and financial theories. In addition, the discussion problematizes the neoclassical view on economics based on the notion that a combination of rationality and irrationality is prevalent among investors. Further research is essential either to support or reject the performance affecting variables and the allocation strategy specified in the thesis. / Det växande intresset att investera på de finansiella marknaderna implicerar att konkurrensen hårdnar bland fondförvaltare. Fondförvaltare för svenska aktiefonder måste därmed skapa andelsägarvärde, oberoende av det makroekonomiska läget. Den finansiella marknaden återhämtade sig snabbt under det första kvartalet 2019 efter den branta nedgången under det föregående kvartalet. Studien avser att identifiera de bidragande faktorerna till avkastning för svenska aktiefonder under denna återhämtning. Multipel linjär regression används för detta ändamål samt för att formulera en avkastningsmaximerande strategi. Strategin föreslår att förvaltare för svenska aktiefonder bör undervikta småbolag, övervikta aktier inom energi och teknik samt undervikta aktier i kommunikationssektorn. Strategin är vidare att vara neutral till överviktad i övriga sektorer. Dessutom är strategin att övervikta nordamerikanska aktier och att undervikta västeuropeiska aktier. Övervikten i Nordamerika ska vara större i absoluta termer än undervikten i Västeuropa. Strategin är tvetydig då den bygger på data från enbart en marknadsåterhämtning. Därmed är den framtagna strategin inte bevisad att vara applicerbar på vilken marknadsåterhämtning som helst. Analysen är baserad på modern makroekonomisk och finansiell teori. Diskussionen problematiserar den neoklassiska synen på ekonomi baserat på uppfattningen att investerare är både irrationella och rationella i sina investeringsbeslut. Fortsatt forskning är essentiell för att antingen stärka eller förkasta dragna slutsatser i denna studie.

In 2011 Storvreta IK installed two solar collector systems in order to reduce the club’s electricity demand for domestic hot water. However, electricity use from 2012 to 2015 shows that the expected reduction in the electricity demand has not occurred. This project investigates the solar collector systems and the heat demand of Storvreta IK’s buildings in order to explain the “failure” in electricity savings. The results of the simulations show that the heat production of the solar collectors is lower than Storvreta IK’s expectations. This could be explained by that the domestic hot water is not used as much as Storvreta IK thought and the system is therefore over-dimensioned for their need. The rebound effect could be another reason to why the electricity saving is lower than expected.

This thesis investigates three major aspects of energy consumption rebound effects (RE) in three papers. More specifically, the issues addressed are (i) the magnitude of economy-wide rebound effect (ii) the role of energy policy instruments in mitigating it and (iii) its channels of impact. The research begins with the estimation of cross-country economy-wide rebound effects for a panel of 55 countries over the period 1980 to 2010. A two-stage approach is utilized in which energy efficiency is first estimated from a stochastic input distance frontier (SIDF). The estimated energy efficiency is then used in a second stage dynamic panel model to derive short-run and long-run RE for an array of developing and developed countries. The cross-country point estimates indicate substantial RE magnitudes across sampled countries during the period under consideration, although a positive and encouraging finding is the declining RE trend across most of the sampled countries during the study period. The second paper contains an RE benchmark for 19 EU countries, as well as an investigation of the effects of two energy policy instruments (energy taxes and ener-gy R&D) on RE performance over the period 1995 to 2010. The results indicate that RE performance improved over the sample period, reinforcing the results from paper one. In addition, there is also some evidence suggesting that binding market-based instruments such as energy taxes have been more effective in restricting RE than in-direct instruments such as energy R&D during the period under consideration. This is consistent across both estimated model specifications. An important observation from the first essay is the slightly larger average RE across the non-OECD countries. For this reason, the last empirical chapter evaluated the channels through which RE stimulated energy use across productive sectors of major developing/emerging economies, namely Brazil, Russia, India, Indonesia and China. To achieve this, the essay relied on duality theory to decompose changes in energy demand into substitution and output effects through the estimation of a trans-log cost function using data spanning 1995-2009. Findings reveal that energy use elasticities across sampled sectors/countries are dominated by substitution effects. One intriguing result that also emerges from this analysis is the role of economies of scale and factor accumulation, rather than technical progress, in giving rise to eco-nomic growth and energy consumption in these countries during the period under consideration.

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Evidências crescentes mostram que os distúrbios de sono associados à doença de Parkinson (DP) são mais relacionados à doença per se, do que apenas fenômenos secundários. Dados apresentados pela literatura sugerem a hipótese de que o sistema dopaminérgico nigroestriatal esteja envolvido na regulação de padrões de sono. Demonstrou-se no presente trabalho que uma lesão de 50% dos neurônios dopaminérgicos residentes na substância negra pars compacta (SNpc) foi capaz de gerar um prejuízo em diversos parâmetros de sono em ratos. Essa redução neuronal provocou uma diminuição importante na porcentagem de sono paradoxal durante os três primeiros dias de registro de sono. Observou-se também uma forte correlação (r=0.91) entre o número de neurônios e a porcentagem de sono paradoxal. A partir disso, propomos que os neurônios dopaminérgicos presentes na SNpc possuem um papel fundamental para a regulação dos padrões de sono, particularmente na promoção de sono paradoxal. Em outro experimento, apresentamos evidências de que a proteína tirosina hidroxilase (TH) encontra-se com sua expressão reduzida no sistema dopaminérgico nigroestriatal após um período de 24 h de privação de sono paradoxal (PSP) em camundongos. De acordo com esses resultados, sugerese que a redução da expressão da TH, produzida pela (PSP), possa explicar em parte a existência da supersensibilidade dopaminérgica de receptores D2. As implicações dessas alterações podem reverberar diretamente sobre anormalidades motoras e de sono encontradas em pacientes portadores da DP. xiii Achados eletrofisiológicos demonstraram que o bloqueio dos receptores D2 (por haloperidol) produziu uma redução de sono paradoxal durante o período de rebote, realizado após 96 h de PSP. Essa redução foi acompanhada por um incremento de sono de ondas lentas, o que possivelmente tenha ocorrido em decorrência de um observado aumento de eficiência de sono. Os resultados também indicaram que a administração de piribedil não pôde gerar um aumento adicional de sono paradoxal. Sugerimos a existência de uma ação particular da neurotransmissão dopaminérgica recaindo sobre a ativação dos receptores D2. As evidências demonstradas no presente trabalho e na literatura permitem sugerir que os neurônios dopaminérgicos presentes na SNpc e na aérea tegmental ventral podem ser considerados essenciais para a regulação de sono, em particular no disparo e manutenção do sono paradoxal, respectivamente. Propõe-se que o paradigma que envolve a dopamina como sendo responsável apenas pela vigília, não é totalmente acurado. A teoria proposta nessa tese alega que esse neurotransmissor pode apresentar uma importante participação em ambos os estados: vigília e sono, e que cada estado deva ser gerado por intermédio de diferentes graus de modulação dopaminérgica. A conclusão delineada a partir desses achados é que a dopamina apresenta implicações significantes na regulação de sono, e essa condição particular deve ser considerada em relação ao tratamento de pacientes com a DP. / Dopamine (DA) is critically involved in regulating neural processes responsible for complex movements and emotions. Alterations in central dopaminergic neurotransmission have been implicated in important neurological and psychiatric disorders such as Parkinson’s disease (PD) and schizophrenia. In addition, DA has recently been recognized as instrumental in the regulation of sleep-wake states. Herein, we present evidence that tyrosine hydroxylase (TH) is down-regulated in the nigrostriatal pathway after 24 h of sleep deprivation (SD) in mice. To identify the involvement of DA in SD and sleep rebound (R) we administered reserpine (1 mg/kg) associated to a-methyl-p-tyrosine (aMT) (250 mg/kg) to produce DA depletion, and rotenone (10 mg/kg) to increase striatal DA turnover. Behavioral tests (catalepsy, grasping and open-field) were conducted to evaluate muscular rigidity and motor alterations inflicted by the drugs immediately after SD and R. Western blot and immunohistochemistry demonstrated that SD alone produced important down-regulation on TH protein expression within the substantia nigra (SN), without affecting the number of dopaminergic neurons. Pharmacological depletion of DA or increase of its turnover affected the entire nigrostriatal pathway. We propose that downregulation of TH expression produced by SD greatly explains the existence of supersensitivity of dopaminergic D2 receptors, especially along the nigrostriatal pathway, and suggest a novel role of DA in the mediation of sleep-wake states as a consequence of the modulation of TH protein expression along that pathway. The implications of these alterations may directly reverberate in motor and sleep abnormalities found in patients with PD. / TEDE / BV UNIFESP: Teses e dissertações

Le béton projeté est une méthode de mise en place consistant en la projection pneumatique de béton sur une surface à grande vitesse. Dans le cas de la méthode par voie sèche, le mélange granulats-ciment est introduit sec en machine, l'eau est ajoutée à la fin du transfert. Cette technique, très employée, est néanmoins génératrice de pertes importantes par rebond, pouvant s'élever jusqu'à 40% de la masse projetée. L'enjeu de la réduction des pertes est à la fois économique et environnemental. Les facteurs influents sur le rebond sont liés aux techniques de projection et à la formulation. Ce travail de thèse a pour objectif l'optimisation de la formulation du béton afin de réduire les pertes par rebond, mais également d'améliorer la durabilité. L'étude porte en particulier sur l'influence sur le rebond : du squelette granulaire, de la teneur en eau et de l'emploi d'additifs et/ou d'additions de substitution. Une approche modélisation du phénomène de rebond est également abordée. / Sprayed concrete is a concrete pneumatically projected onto a surface at high velocity. Dry-mix shotcrete is a process in which dry constituents are introduced into the machine and conveyed through a hose to the nozzle, where the water is added. This process is used in various civil engineering or construction projects; unfortunately, it can lead to high losses of concrete due to rebound (up to 40% of the total mass of material). Such losses induce overconsumption of material, which is damaging for the cost of the work and for the environment. Rebound depends on technicals parameters and mix design. The present work focuses on rebound reduction and also on durability enhancement by modification of the mix design. The influence of aggregate size distribution, water content and supplementary cimentitious material is studied. An analytical approach of rebound phenomenon is also implemented.

Human motor control is a complex process involving both central and peripheral components of the nervous system. Type Ia afferent input contributes to both motor unit recruitment and firing frequency, however, whether maximal force production is dependent on this input is unclear. Therefore, chapter 2 examined maximal and explosive force production of the knee extensors following prolonged infrapatellar tendon vibration; designed to attenuate the efficacy of the homonymous Ia afferent-α-motoneuron pathway. Despite a marked decrease in H-reflex amplitude, indicating an attenuated efficacy of the Ia afferent-α-motoneuron pathway, both maximal and explosive force production were unaffected after vibration. This suggested that maximal and explosive isometric quadriceps force production was not dependent upon Ia afferent input to the homonymous motor unit pool. Voluntary movements are linked with various modulations in ongoing neural oscillations within the supraspinal sensorimotor system. Despite considerable interest in the oscillatory responses to movements per se, the influence of the motor parameters that define these movements is poorly understood. Subsequently, chapters 3 and 4 investigated how the motor parameters of voluntary contractions modulated the oscillatory amplitude. Chapter 3 recorded electroencephalography from the leg area of the primary sensorimotor cortex in order to investigate the oscillatory responses to isometric unilateral contractions of the knee-extensors at four torque levels (15, 30, 45 and 60% max.). An increase in movement-related gamma (30-50 Hz) activity was observed with increments in knee-extension torque, whereas oscillatory power within the delta (0.5-3 Hz), theta (3-7 Hz), alpha (7-13 Hz) and beta (13-30 Hz) bands were unaffected. Chapter 4 examined the link between the motor parameters of voluntary contraction and modulations in beta (15-30 Hz) oscillations; specifically, movement-related beta decrease (MRBD) and post-movement beta rebound (PMBR). Magnetoencephalography (MEG) was recorded during isometric ramp and constant-force wrist-flexor contractions at distinct rates of force development (10.4, 28.9 and 86.7% max./s) and force output (5, 15, 35 and 60%max.), respectively. MRBD was unaffected by RFD or force output, whereas systematic modulation of PMBR by both contraction force and RFD was identified for the first time. Specifically, increments in isometric contraction force increased PMBR amplitude, and increments in RFD increased PMBR amplitude but decreased PMBR duration. Physical fatigue arises not only from peripheral processes within the active skeletal muscles but also from supraspinal mechanisms within the brain. However, exactly how cortical activity is modulated during fatigue has received a paucity of attention. Chapter 5 investigated whether oscillatory activity within the primary sensorimotor cortex was modulated when contractions were performed in a state of physical fatigue. MEG was recorded during submaximal isometric contractions of the wrist-flexors performed both before and after a fatiguing series of isometric wrist-flexions or a time matched control intervention. Physical fatigue offset the attenuation in MRBD observed during the control trial, whereas PMBR was increased when submaximal contractions were performed in a fatigued state.

I denna magisteruppsats kommer strategiska lägen och boplatsers relation till gravar att studeras. Arbetet riktas in på Arnäs och Själevad socken i Örnsköldsvik kommun som ligger in Västernorrlands län. Mer specifikt så är det järnåldersboplatser i Skommarskatan, Gene, Vågnäs and Sörvåge som inkluderas i uppsatsen. Terrängmodellerings kartor, viewsheds, landhöjnings kartor och historiska kartor, litteratur samt fältinventering används för att komma fram till vilket sätt boplatser blev strategiskt belagda och vilken rumslig relation det finns mellan boplatser och gravar. Det visar sig att gravar verkar vara anlagda nära boplatser, men resultatet tyder på att man inte nödvändigtvis ser gravarna från boplatserna på boplatslokalerna. Resultaten visar att viewsheds inte alltid stämmer med det man ser i fält.Resultatet antyder på att terräng, relation till vatten, närhet till färskvatten, kommunikation möjligheter, handelsmöjligheter, resurstillgångar, huskonstruktion och på vilket sätt människorna livnärde sig på har en inverkan på vilket sätt boplatser anlades. Tidigare så har mycket fokus varit lagt på hur RAÄ 22:1 i Gene var strategiskt lagd inom arkeologisk forskning, men i den här uppsatsen har fokus legat på andra typer av boplatser och andra delar av landskapet med hänsyn till fler lokaler. Denna studie har demonstrerat att tidigare studier av järnåldersboplatser i Arnäs och Själevad socken har varit begränsad i sin syn att belysas boplatsers relation till landskapet. Tidigare forskning var fokuset på en lokal och det har visat sig vara en brist när man jämför med landskaps studiemetoder använda i denna studie. Nu har agrara, jägare-samlare och säljägare boplatser studerats och vidgat perspektivet på boplatser strategiska lägen inom studieområdet.

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The circular economy presents a promising framework for sustainable production and consumption by emphasizing resource conservation through practices such as recycling, reuse, and remanufacturing. However, a systematic analysis of these aspects remains underexplored, particularly regarding the comprehensive evaluation of displacement or substitution effects and the broader implications of circular practices on resource conservation. This study aims to fill this gap by conducting a systematic literature review, evaluating the extent to which circular activities mitigate resource extraction and their influence on the substitution or displacement between primary and secondary materials and products.  The findings reveal that the effectiveness of circular economy strategies is dependent on their capacity to successfully displace virgin raw materials and prevent rebound effects. It also highlights the variability in outcomes based upon various factors including the business models, consumer behaviour, type of materials, and circular practices employed. It highlights the need for comprehension of how circular economy practices influence demand for new products and the substitution between primary and secondary materials.   This research contributes to a deeper understanding of the conditions under which circular economy strategies can effectively reduce resource use, including suggestions for future studies aimed at enhancing the resource conservation efficiency of circular initiatives and by identifying key gaps in current research, it supports the development of more sustainable production and consumption models. / Den cirkulära ekonomin presenterar ett lovande ramverk för hållbar produktion och konsumtion genom att betona resursbevarande metoder som återvinning, återanvändning och återtillverkning. En systematisk analys av dessa aspekter är dock fortfarande underutforskad, särskilt när det gäller den omfattande utvärderingen av förskjutningseffekter och de bredare konsekvenserna av cirkulära behandlingssätt för resursbevarande. Den här studien syftar till att fylla den luckan genom att genomföra en systematisk litteraturanalys, som utvärderar i vilken utsträckning cirkulära aktiviteter minskar resursutvinning.  Resultaten avslöjar att effektiviteten hos strategier för cirkulär ekonomi är beroende av deras förmåga att framgångsrikt ersätta jungfruliga råmaterial och förhindra återverkningseffekter (rebound effect). Den belyser också variationen i resultat baserat på olika faktorer, inklusive affärsmodeller, konsumentbeteenden, typ av material och vilket cirkulärt behandlingssätt som används. Dessutom understryker resultatet behovet av en nyanserad förståelse för hur cirkulär ekonomi påverkar efterfrågan på nya produkter och substitutionen mellan primära och sekundära material.   Studien bidrar till en djupare förståelse av under vilka förutsättningar strategier för cirkulär ekonomi effektivt kan minska resursanvändningen samt förslag på framtida studier som syftar till att förbättra resursbevarandeeffektiviteten inom cirkulära initiativ.

Cette étude vise à une meilleure compréhension des phénomènes rencontrés en filtration des aérosols nanométriques, c’est-à-dire inférieurs à 100 nm, neutres et/ou chargés. Pour ce faire, trois différents types de média ont été étudiés : des grilles, en acier et matières synthétiques, des filtres non tissés, en fibres de verre ou polymériques, et des lits granulaires, constitués de billes d’acier ou de zéolithe. Il ressort des résultats expérimentaux obtenus que quel que soit le média testé, l’efficacité de collecte des particules augmente lorsque le diamètre de l’aérosol diminue, et ce jusque 4 nm. Ceci entre en contradiction avec l’approche théorique dite du rebond thermique, développée par Wang et Kasper en 1991, selon laquelle l’efficacité de collecte serait susceptible de diminuer en-dessous de 10 nm. La vérification des calculs de Wang et Kasper permet d’expliquer cette incohérence, et montre, à partir de valeurs plus réalistes de l’énergie d’adhésion particule-fibre, que si le rebond thermique existe, celui-ci ne pourra se manifester qu’en-dessous de 1 nm, au mieux. Ainsi, les perméances expérimentales des différents médias testés ont pu être modélisées en tenant compte des mécanismes de collecte par diffusion et/ou par effets électrostatiques. Une étude originale sur les performances, dans le domaine nanométrique, de filtres en fibres de verre intentionnellement percés complète ce travail. Pour un même média fibreux, la perméance augmente avec le diamètre de perforation réalisée. Par ailleurs, pour une taille de perforation donnée, la perméance devient indépendante du diamètre des particules en-dessous d’une taille limite, fonction de la dimension de la perforation. Il a enfin été mis en évidence que la baisse d’efficacité est d’autant plus importante que la résistance à l’écoulement de l’air du filtre est importante. Un modèle semi-empirique, fondé sur la différenciation du flux d’aérosol traversant la fuite du flux traversant le matelas fibreux résiduel du filtre, permet de bien représenter ces états de fait / This study aims to better understand the mechanisms encountered in nanoparticles aerosol filtration, the particles being charged or not. Three different types of media were studied: stainless steel or synthetics wire screens, unwoven filters in glass or polymer fibres, and at last, granular beds made from steel or zeolite balls. Experimental results show that, whatever the media, collection efficiency increases as the particle diameter decreases down to 4 nm. This point conflicts with the so-called thermal rebound effect developed by Wang and Kasper in 1991, according to which collection efficiency could decrease below 10 nm. The checking of Wang and Kasper’s calculations enables to explain this discrepancy and shows from more probable particle-to-fibre adhesion energy values that if thermal rebound phenomenon exists, it would only be measurable below 1 nm. Then, experimental points can be modelled from both diffusion and electrostatic forces collection mechanisms. An investigation on the filtration behaviour of fibreglass filters in the nanometric domain when intentionally-pierced with calibrated needles completes the above-mentioned works. For a same media, penetration increases as the leak diameter does. On the other hand, for a given hole size, penetration becomes independent of the particle diameter below a critical scale, which is a function of the leak diameter. It was lastly shown that the efficiency of a pierced media decreases all the more that its air flow resistance is higher. A semi-empirical model based on the differentiation between the aerosol flow across the leak and the one through the residual fibrous bed of the filter enables to well represent these points