The coronavirus disease 2019 (COVID-19) pandemic is provoking a global public health crisis. Even though the academic world is intensively pursuing new therapies, there is still no “game changer” in the management of COVID 19. The Mammalian Target of Rapamycin (mTOR) is an ancient signaling system that has been proposed as a molecular tool used by coronaviruses and other RNA and DNA viruses in order to replicate and persist in the host cell. In recent years, Intermittent Fasting (IF), a practice consisting on a strict calorie restriction during a prolonged period of time during the day, has gained popularity due to its potential benefits in multiple health systems and in regulating inflammation. IF inhibits the mTOR pathway which is similar to the effects of Rapamycin in some animal models. mTOR inhibition and promotion of autophagy could potentially be the link between the possible direct benefits of IF in COVID-19 due to the interruption of the viral cycle (protein synthesis). Besides, IF has shown to be a strong anti-inflammatory in multiple prior studies, and may play a role in attenuating COVID -19 severity. This review hypothesizes the possible intersection between viral, immunological, and metabolic pathways related to mTOR and the potential mechanisms through which IF may improve clinical outcomes. Future prospective randomized controlled clinical trials to evaluate intermittent fasting (IF) regimens in order to prevent and treat moderate to severe forms of COVID-19 in humans are needed. / Revisión por pares

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

In intermittent streams, hydrological variation is probably the single-most important factor affecting fish assemblage structure. While the response of aquatic assemblages to seasonal or annual variation in hydrology is well-known, less attention has been devoted to how assemblages respond to natural, intraseasonal drought. To explore this question, I conducted summer surveys of fish and aquatic insect assemblages occupying pool refugia in first to third order, intermittent streams in the Saline river drainage in the Ouachita highlands (central Arkansas, U.S.A.)(2001?2003). The goals of this project were: 1) to relate assemblage variability of fishes and aquatic insects to environmental gradients during summer drying of streams; 2) to characterize the variability of fish assemblages occupying pool refugia, which differed in quality along a spatial gradient; and, 3) to determine the population genetic structure of five fish species across the intermittent landscape. Hydrological variables explained significant variation in assemblage variability for fishes. In contrast, variability in aquatic insect assemblages was related to water quality variables. These patterns are similar to those observed at larger scales of space and time. As pools dried, neither fish species richness nor the slope of the species-area relationship changed. However, the structure of many assemblages was variable over time. Pools with a relatively stable hydrology were sources of reproduction and high population growth, low extinction and high immigration. Sites that exhibited a more variable hydrology (drying completely or nearly-so) were sinks characterized by population declines. The majority of sites had minimal population growth, and intermediate immigration and extinction rates, and were dubbed metapopulations. Immigration and extinction dynamics had important effects on population genetics for common fish species. Two common species had relatively high immigration rates and showed no population differentiation. Populations of three species showed differentiation that was not related to geographic distance among sites. Instead, local extinction of rare haplotypes and evidence of recent bottlenecks suggested that ecological attributes associated with summer drought affected population differentiation. It is clear that retaining the natural hydrology of stream systems contributes to the maintenance of biodiversity, and the conservation of complex demographic processes and genetic patterns.

No description available.

No description available.

The conventional computing techniques are based on the assumption of a near constant source of input power. While this assumption is reasonable for high-end devices such as servers and mobile phones, it does not always hold in embedded devices. An increasing number of Internet of Things (IoTs) is powered by intermittent power supplies which harvest energy from ambient resources, such as vibrations. While the energy harvesters provide energy autonomy, they introduce uncertainty in input power. Intermittent computing techniques were proposed as a coping mechanism to ensure forward progress even with frequent power loss. They utilize non-volatile memory to store a snapshot of the system state as a checkpoint. The conventional security mechanisms do not always hold in intermittent computing. This research takes a top-down approach to design secure intermittent systems. To that end, we identify security threats, design a secure intermittent system, optimize its performance, and evaluate our design using embedded benchmarks. First, we identify vulnerabilities that arise from checkpoints and demonstrates potential attacks that exploit the same. Then, we identify the minimum security requirements for protecting intermittent computing and propose a generic protocol to satisfy the same. We then propose different security levels to configure checkpoint security based on application needs. We realize configurable intermittent security to optimize our generic secure intermittent computing protocol to reduce the overhead of introducing security to intermittent computing. Finally, we study the role of application in intermittent computing and study the various factors that affect the forward progress of applications in secure intermittent systems. This research highlights that power loss is a threat vector even in embedded devices, establishes the foundation for security in intermittent computing. / Doctor of Philosophy / The embedded systems are present in every aspect of life. They are available in watches, mobile phones, tablets, servers, health aids, home security, and other everyday useful technology. To meet the demand for powering up a rising number of embedded devices, energy harvesters emerged as a solution to provide an autonomous solution to power on low-power devices. With energy autonomy, came energy scarcity that introduced intermittent computing, where embedded systems operate intermittently because of lack of constant input power. The intermittent systems store snapshots of their progress as checkpoints in non-volatile memory and restore the checkpoints to resume progress. On the whole, the intermittent system is an emerging area of research that is being deployed in critical locations such as bridge health monitoring. This research is focused on securing intermittent systems comprehensively. We perform a top-down analysis to identify threats, mitigate them, optimize the mitigation techniques, and evaluate the implementation to arrive at secure intermittent systems. We identify security vulnerabilities that arise from checkpoints to demonstrate the weakness in intermittent systems. To mitigate the identified vulnerabilities, we propose secure intermittent solutions to protect intermittent systems using a generic protocol. Based on the implementation of the generic protocol and its performance, we propose several optimizations based on the needs of the application to securing intermittent systems. And finally, we benchmark the security properties using two-way relation between security and application in intermittent systems. With this research, we create a foundation for designing secure intermittent systems.

The most common type of nitrogen removal in wastewater treatment plant is to use abiological treatment. When biological treatment is used, the two most common processes fornitrogen removal is pre and post denitrification. In the biological treatment A (BA) atKungsängsverket the nitrogen removal process used is intermittent aeration. Whenintermittent aeration is used, the wastewater is aerated at specific time intervals. This allowsboth nitrification and denitrification to occur in the same water volumes. It is of great interestto find a control strategy for controlling the air supply which is both cost effective and leadsto low emissions of nitrogen. The aim of this project was to improve the intermittent aeration at Kungsängsverket, Uppsala.The project was divided into two parts. The first part consisted of experiments carried out infull scale on the plant and the second part was a simulation study. In the experimental partdifferent time intervals for aeration were evaluated. The aim of the simulation part was toevaluate different control parameters and to find which parameters that should be used for anoptimal control strategy. The results showed that the best combination of aerated time and un-aerated time is 50minutes aerated and 50 minutes unaerated. It is recommended that the wastewater should beadded in the beginning and after half of the plant. The simulation results showed that thecontrol strategy can be improved by using a PI-regulator. The experiments and thesimulations both showed clear signs of variations in the inflow during the day. Because of thisit is recommended to establish a control strategy which easily can change the aeration timedepending on low and high flows. / Biologisk rening av avloppsvatten är den vanligaste typen av kväverening vidavloppsreningsverk. Bioblock A, Kungsängsverket Uppsala, har efter en renovering fått dettidigare driftsättet, kaskadkväverening, utbytt mot intermittent luftning. Intermittent luftninginnebär att nitrifikation och denitrifikation sker i samma zoner. Luftningen startas och stängsav med jämna tidsintervall vilket skapar en miljö för både nitrifikation och denitrifikation. Detär av stort intresse att finna en fungerande styrstrategi för luftningen som både ärkostnadseffektiv och som ger låga halter av kväve i utgående vatten. Syftet med examensarbetet var att effektivisera den intermittenta luftningen vid bioblock Avid Kungsängsverket, Uppsala. Tillvägagångsättet var att genom en utvärdering av detnuvarande driftsättet se vad som kunde förbättras. Det ställdes därefter upp ett antal försöksom var inriktade på att finna bättre driftparametrar. Dessa experiment genomfördes ifullskala. Därefter genomfördes en simuleringsstudie där dagens relästyrning jämfördes medtre regleralternativ. Det första alternativet var att reglera luftningen med hjälp av en PIregulator.De andra två alternativen var att styra luftningsperioderna efter utgåendeammonium-respektive nitrathalt. Fullskaleförsöken indikerade att luftning påslagen i 50 minuter följt av avslagen i 50 minutergav den högsta kvävereduktionen av de undersökta alternativen. Bioblock A är uppdelad ifem olika linjer vilka i sin tur är uppdelade i zoner. Utifrån försöken kan det rekommenderasatt avloppsvattnet tillsätts till första zonen och efter hälften av linjen, istället för som vid dennuvarande driften då vattnet tillsätts efter en fjärdedel och efter hälften av linjen. Simuleringsstudien visade att om dagens relästyrning byttes ut mot en PI-regulator skullesyretopparna minskas och syrehalten stabiliseras vid det förinställda börvärdet. Resultatenfrån både simuleringsstudien och fullskaleförsöken visar att en tidsstyrning avluftningsperioderna är av intresse för att spara energi och få en bättre kväverening.

L’optimisation de la performance en endurance oblige l’athlète à répéter des séances d’entraînement intermittent à haute intensité (EIHI), ce qui génère une fatigue neuromusculaire qui peut être préjudiciable. Ce type d’EIHI peut être aussi à l’origine des perturbations importantes de l’homéostasie générale affectant ainsi le volume plasmatique et les réponses physiologiques. Ainsi, l’objectif de ce travail de thèse est d’étudier l’effet de l’intensité d’EIHI (100% vs. 110% de VMA) sur les performances en endurances, marqueurs des dommages musculaires, le volume plasmatique et les réponses inflammatoires suite à l’exercice intermittent. Pour les études 2, 3 et 4, quatre groupes de sujets masculins et sains ont participé à ce travail. Ils ont été répartis d’une façon aléatoire en 2 groupes expérimentaux (GE100 et GE110) et en 2 groupes contrôles (GC100 et GC110). Pour l’étude 1, seulement 3 groupes (GE100, GE110 et GC) ont participé à l’expérimentation. En effet, deux programmes d’EIHI ont été mis à disposition avec un EI à 100% de VMA (pour GE100) et un EI à 110% de VMA (pour GE110). Les résultats montrent que l’EIHI s’accompagne d’une augmentation significative du volume plasmatique chez les deux groupes entrainés. Ces changements du volume plasmatique ont été accompagnés par une augmentation des performances physiques mesurée lors de l’exercice maximal à charge croissante et lors de l’exercice intermittent chez les groupes entrainés. Nos résultats ont révélé un taux d’amélioration plus élevé en suivant un EIHI à 110% de VMA. Des adaptations endocriniennes sont probablement à l’origine de ces modifications liées à l’entrainement intense. En effet, après entrainement, nous avons observé une diminution significative des marqueurs des dommages musculaires (au repos et à l’exercice intermittent) chez les sujets entrainés par rapport aux groupes contrôles. La différence liée à l’intensité de l’EIHI disparait après entrainement seulement entre les groupes entrainés. Le même constat a été observé concernant les concentrations plasmatiques des cytokines. En conclusion de ce travail de thèse, il semble que l’augmentation de l’intensité d’EIHI serait un bon moyen pour réduire et atténuer les effets délétères de l'EI supra-maximal. Le majeur fruit de ce travail est que l'intensité de 110% de VMA provoque une meilleur amélioration des performances aérobies que 100% de VMA, tout en avoir le même niveau de variation plasmatique, voir même des préférences au niveau des réponses inflammatoires. / Optimization of endurance performance requires the athlete to repeat high intensity interval training (HIIT). This type of training can induce a neuromuscular fatigue, a homeostasis perturbation which affects the plasma volume and the physiological responses. Thus, the aim of this study is to examine the effect of increasing HIIT intensity (100% vs. 110% of VMA) on endurance performance, muscular damage marker, plasma volume and inflammatory responses after an intermittent exercise (IE). For the first study, only 3 groups (EG100, EG110 and CG) participated in the experiment. However, in the2 sd, 3rd and 4th studies, 39 male volunteered to participate in this study. They were randomly assigned in control groups (CG100 and CG110), trained group with 100% of maximal aerobic velocity (MAV) (EG100) and trained group with 110% MAV (EG110). The training program consisted of 3 sessions a week during 8 weeks and presented only 30/30s IE. Before and after HIIT, participants performed a maximal graded test (MGT) and IE test at 100% or 110% MAV with 30s recovery at 50% MAV. Blood was collected at rest, at the end of the IE and after 15min of passive recovery. Results showed that increasing IT running intensity by 10% of MAV increases significantly the PVV at rest and after the IET. Despite the fact that EG100 and EG110 had the same PVV rise level after HIIT, greater aerobic performances were recorded in EG110. Our results revealed a higher improvement in response to HIIT at by following a 110% VAM EIHI. Endocrine adaptations are probably the cause of these changes related to intense training. Indeed, after training, we observed a significant decrease in markers of muscle damage (resting and intermittent exercise) in subjects trained compared to control groups. The difference related to the intensity of the EIHI disappears after training only between the groups trained. The same observation has been observed concerning the plasma concentrations of cytokines. In conclusion of this thesis work, it seems that increasing the intensity of EIHI would be a good way to reduce and mitigate the deleterious effects of the supra-maximal EI. In conclusion, HIIT at 110% MAV provoked better aerobic performances than 100% MAV, while having the same plasma volume and inflammatory responses levels.

<p>Våra kyrkor är en viktig del av samhället, och är en kulturskatt som måste vårdas. Kyrkorna använder dock väldigt mycket energi till uppvärmning varje år. Detta beror på att de flesta av dem är gamla och att energieffektivitet ej varit en prioriterad fråga i deras verksamhet. Grinstad kyrka är en kyrka med hög energianvändning som trots att den endast är uppvärmd vid förrättningar använder lika mycket energi som två medelvillor. Kyrkan är från 1200-talet, är byggd i tegel och värms idag upp av en oljepanna i ett vattenburet system samt några elradiatorer. Det finns planer på att byta ut oljepannan mot närvärme.</p><p>Syftet med examensarbetet var att undersöka och ge församlingen en inblick i vart den energi som tillförs kyrkan tar vägen, hur mängden tillförd energi kan minskas genom energieffektiviseringsåtgärder samt vilken miljöpåverkan värmekällan i dagens uppvärmningssystem har jämfört med värmekällan i det planerade närvärmenätet.</p><p>Målet var att svara på följande frågor:</p><p>•Var sker de största energiförlusterna i kyrkan och hur skall dessa kunna minskas genom energieffektiviseringsåtgärder?</p><p>•Hur skall kyrkans värmesystem dimensioneras med avseende på kyrkans värmeeffektbehov?</p><p>•Hur skulle miljöpåverkan till följd av kyrkans uppvärmning förändras vid anslutning till det planerade närvärmenätet.</p><p>Det värmesystem som ansågs passa Grinstad kyrka bäst var ett vattenburet värmesystem som värmer kyrkan intermittent. Det ansågs även lämpligt att värma upp på 6 timmar från en grundtemperatur av 8°C till en förrättningstemperatur av 18°C. Värmesystemet måste då ha effekten 22,5 kW, vilket är en effekt som är högre än dagens system kan avge. Därför gavs förslaget att komplettera dagens system med kamflänsrör under några av kyrkbänkarna.</p><p>De största energiförlusterna i kyrkan visade sig vara genom taket och genom att isolera detta kan förlusterna genom det minskas med 85 %. Grundtemperaturen i kyrkan är idag högre än vad som behövs och genom att sänka den 4ºC kan energianvändningen för grundvärmen minskas med 18 %.</p><p>Bytet från en central oljepanna till biobränsleeldad närvärme skulle leda till att utsläppen av koldioxid och svavel att minska, medan utsläppen från stoft, koloxid och svavel kommer att öka.</p> / <p>Our churches are an important part of the community, and a cultural treasure that need to be preserved. The most of the churches are old and energy efficiency has not been prioritized earlier. Because of that the churches uses a lot of energy for heating each year. The church in Grinstad is a church with high energy usage. It is not frequency used, but in spite of that it uses as much energy for heating as two average hoses. The church was built of brick in the 1300th century. The heating system today consists of a couple of electric radiators and an oil furnace connected to a hot water system.</p><p>The purpose of this report was to investigate and to give the congregation in Grinstad insights in where the energy supplied to the church disappears, how the amount of energy supplied could be reduced by energy efficiency actions and also which environmental influence the heating system today has compared to the heat source in the planned small district heating system.</p><p>The aim was to answer these questions:</p><p>•Where do the greatest energy losses in the church occur and how could these be reduced by energy efficient actions?</p><p>•How should the heating system in the church be designed depending on the need for effect of heat in the church?</p><p>•How would the environmental influence change if the church connects to the planned small district heating system?</p><p>The heating system that was considered to be the most suitable for the church in Grinstad was a heat water system that warms up the church intermittent. If the church is heated up from the ground temperature 8°C to the ceremony temperature 18°C in 6 hours the heating system need to have the effect 22,5 kW. This is a higher effect than the system today can emit, and therefore extra radiators need to be installed.</p><p>Calculations showed that the greatest energy losses in the church occurred through the roof. By isolating it the losses could be reduced by 85 %. Today the ground temperature is higher than needed. If the ground temperature is decreased with 4ºC, the energy usage for ground heating could be reduced with 18 %.</p><p>By changing from the oil furnace to biofuel fired small district heating the emission of carbon dioxide and sulphur will decrease, and the emissions of dust, carbon monoxide and volatile organic compounds will increase.</p>