By buffering cytosolic calcium, mitochondria can shape the magnitude and duration of intracellular calcium transients, which in turn govern key physiological events. Although controlled uptake of calcium into the matrix influences the rate of ATP production, excess calcium within the matrix triggers non-specific permeabilization of the mitochondrial inner membrane, resulting in cell death. Despite its importance in cellular physiology, the molecular identity of the mitochondrial calcium uniporter remained a mystery for nearly five decades. Recently, an approach inspired by comparative genomics was used to identify two proteins required for high-capacity mitochondrial calcium uptake. These include MICU1, an EF-hand protein that may function as a regulatory component by sensing calcium, and MCU, the channel-forming subunit of the uniporter. In this work, I explore two distinct areas within the growing field of molecular mitochondrial calcium biology. First, I discuss the identification of a new protein, MICU1-paralog EFHA1, and present data that implicates it in mitochondrial calcium uptake. Subsequently, I describe efforts to establish an in vitro system to characterize the channel activity of MCU, including my contribution to the development of a liposome-based assay for calcium transport and preliminary work aimed at reconstituting MCU transport activity in proteoliposomes.

Given the growing concern over climate change, air pollution, rising energy prices, and the uncertain reliability of conventional fuel sources, solar power has become more popular in a variety of applications. Solar power is free, safe, abundant, renewable, and has few negative impacts on the environment. The photovoltaic array is substantially influenced with unpredictable environmental conditions (sun illumination and array temperature), which in turn, results in nonlinear Voltage-Current (or Power-Voltage, Power-Current) characteristics. These characteristics make it difficult to estimate the maximum power operating point. To extract the maximum power available from photovoltaic (PV) arrays on a continuous basis, a device called the Maximum Power Point Tracker (MPPT) is needed to continuously deliver the highest possible power to the load given unpredictable variations in environmental conditions. The PV system used in our experiment has a maximum 300W capability. Two sets of PV arrays are used in parallel to demonstrate the scalability of the system; each branch consists of three series-connected PV modules that are individually rated at 50W. Two DC-DC buck-type converters are implemented. A 24V battery bank is used as a power storage unit and is also connected to the load. An MC-based 56F8013 and its demonstration board from Freescale are employed to implement different MPPT control schemes, with multiple-PWM channels. The design can therefore adequately handle two main independent switches for each power converter. Several MPPT control algorithms are validated and comparatively analyzed in both indoor and outdoor experiments in real time. A new control strategy (called Adaptive Hill-Climbing) is proposed as a modified version of the conventional Hill-Climbing method using an optimally adaptive power window. Other methods including dp/dv method and IncCond method are also implemented in the PV system. The experimental investigation is conducted using these control topologies to seek continuously varying Maximum Power Point (MPP) from solar arrays. The experimental results show that the new proposed control method strongly outperforms the other methods. This thesis shows that the proposed MPPT can increase the power generated by PV arrays by up to at least 30% more than a PV system without an MPPT. The proposed MPPT system is adaptive to environmental disturbances; it is flexible and can be expanded to an N-parallel PV system. / Thesis / Master of Applied Science (MASc)

La sénescence est un arrêt stable de prolifération mis en place en réponse à différents stress cellulaires, comme le raccourcissement des télomères (sénescence réplicative) ou le stress oncogénique (sénescence induite par un oncogène, OIS) et constitue un processus s'opposant à la prolifération des cellules tumorales. La plupart des études menées dans des fibroblastes ont permis d'identifier p53 et pRb comme acteurs majeurs de la sénescence. Toutefois, l'étude de l'OIS dans les mélanocytes ou les cellules épithéliales a révélé de nouveaux mécanismes, n'impliquant pas obligatoirement ces deux voies canoniques. L'objectif de ma thèse est de caractériser de nouveaux régulateurs de l'OIS dans les cellules épithéliales. Pour cela deux approches différentes ont été utilisées. Dans une première partie, je me suis intéressée aux effets de l'activité portée par les lysyl oxydases (LOX), famille d'enzyme connue pour favoriser le processus métastatique, sur l'échappement à l'OIS. L'inhibition de LOX et LOXL2 stabilise l'OIS dans les cellules épithéliales mammaires humaines et dans un modèle murin d'adénocarcinomes du pancréas. Ce travail a permis de montrer que l'activité Lox est impliquée dans l'initiation tumorale. Dans un deuxième temps, en utilisant un criblage perte de fonction nous avons isolé plusieurs gènes dont l'inhibition stable d'expression permet un échappement à l'OIS dans les cellules épithéliales mammaire humaines. Parmi eux, j'ai caractérisé l'implication de deux canaux calciques, ITPR2 et MCU, dans l'échappement à la sénescence. ITPR2, qui permet la sortie de calcium du réticulum endoplasmique, et MCU, qui permet l'entrée de calcium dans la matrice de la mitochondrie, s'avèrent être deux acteurs nécessaires à la signalisation calcique lors de l'OIS. De manière importante, les mouvements calciques sont associés à une chute du potentiel de membrane mitochondrial, et à la génération d'espèces réactives de l'oxygène. Ce travail montre que les mouvements calciques semblent également être impliqués dans le processus de sénescence réplicative / Senescence is a stable proliferation arrest triggered by several cellular stresses such as telomeres shortening (replicative senescence) or oncogenic activation (oncogene-induced senescence, OIS). Senescence counteracts proliferation of malignant cells, and as such, constitutes a failsafe program. Senescence was first evidenced in fibroblasts, and most of the following studies were conducted in human or murine fibroblasts, allowing the identification of p53 and pRb pathways as strong regulators of senescence. However the few studies investigating senescence pathways involved in other cell types, such as melanocytes or epithelial cells unveiled new p53/pRB- independent mechanisms. The aim of my thesis was then to characterize new senescence regulators in human epithelial cells. We were first interested in characterizing lysyl oxidase activity (Lox) on OIS escape. LOX enzymes are mainly known to favor metastatic processes. Lox activity inhibition stabilized OIS in vitro, but also senescence in a transgenic murine model of pancreatic ductal adenocarcinoma. This work demonstrated that Lox activity is involved in tumoral initiation by promoting senescence escape. Using a loss-of-function screen, we identified several genes whose down-regulation allowed OIS escape of human mammary epithelial cells. Among them I have characterized ITPR2 and MCU, two calcium-related channels. Loss of ITPR2, known to mediate endoplasmic reticulum (ER) calcium release, as well as loss of MCU, necessary for mitochondrial calcium uptake, enable escape from OIS. During OIS, ITPR2 triggers calcium release from the ER, followed by mitochondrial calcium accumulation through MCU channels. Mitochondrial calcium accumulation leads to a subsequent decrease in mitochondrial membrane potential, reactive oxygen species accumulation and senescence. This ER-mitochondria calcium transport is not restricted to OIS, but is also involved in replicative senescence. Our results show a functional role of calcium release by the ITPR2 channel and its subsequent accumulation in the mitochondria

A long held hypothesis in mitochondrial biology holds that increases in mitochondrial Ca2+ levels stimulate the activity of matrix dehydrogenases that catalyze production of NADH and eventually donate electrons to electron transport in order to increase ATP formation. At the same time, mitochondrial Ca2+ overload is a deleterious event leading to opening of the mitochondrial permeability transition pore, increasing reactive oxygen species and initiating pathways that contribute to cell death. These fundamental hypotheses are best studied in the heart because of the critical energy supply-demand relationship in myocardium, but were untestable in vivo until the discovery of the mitochondrial Ca2+ uniporter (MCU). The molecular identity of the MCU pore forming subunit was recently discovered, which allowed me to study a transgenic mouse with myocardial delimited expression of a dominant negative MCU. My lab developed mice with myocardial-delimited transgenic expression of a dominant negative MCU to test these fundamental hypotheses and to determine how MCU controls physiological and pathological stress responses in vivo, ex vivo, and in situ. My studies provide new, unanticipated information that contributes to our understanding the relationship between mitochondrial Ca2+, oxygen utilization, cardiac pacemaking and pathologic stress responses in heart. Here, I show that mice with myocardial-targeted MCU inhibition have hearts with surprisingly high oxygen consumption rates due to elevated cytoplasmic Ca2+ in response to physiological stress. Loss of MCU effectively preserved inner mitochondrial membrane potential and prevented an oxidative burst thought to drive myocardial injury and death, but nevertheless failed to protect myocardium from ischemia-reperfusion injury. Increases in oxygen consumption, elevation in cytoplasmic Ca2+ and transcriptional reprogramming mitigate the protective actions of MCU inhibition in vivo. Mice with myocardial selective MCU inhibition have a reduced response to isoproterenol-induced heart rate increase but have normal baseline heart rates. My studies provide novel insight into how MCU contributes to myocardial Ca2+ homeostasis, metabolism, and transcription leading to surprising actions on physiological and pathophysiological responses in heart.

In the field of automatic control, using a microprocessor application system to monitor and control an automatic system is quite common and its usage rate are still increasing. Microprocessor can support complex processes scheduling, and accurately control on time and position. However, even a highly professional programmer still needs a lot of time to maintain the control programs running on this kind of control system. The advent of the programmable logic controller (PLC), which consists of CPU, data memory, digital and analog I/O port, and power module provides an alternative for designing an automatic system. It¡¦s used in the field of industrial control widely. Compared to the microprocessor-based control systems, the PLC-based control systems have the advantage of providing a development environment for easily programming and maintaining. However, the high cost, poor signal processing ability, and the restriction on the function of device are the major drawbacks of PLC. To solve the problems described above, this paper taking the advantages from the PLC-based microprocessor-based control systems proposes a PLC-like development environment for creating a microprocessor- based control system. To accomplish this goal, according to the object- oriented concept, this paper classified the device in a microprocessor into four categories, GPIO, ADC, Timer and Serial-com. And also provides an interface window for users to set and access device register. In addition, this paper provides a set of user customizable task module tools to easily establish a PLC-like based system. Then system developers can write a program via a simple event-table-driven way, and build up the operating procedures according to the approach of sequential multitasking. Our research result make the building of microprocessor-based system can be clearly divided in to three stages, microprocessor manufacturer, advance user, and generally user which not only makes the development of product easier and faster but also meets the time-to-market demands. In the future, some advanced technologies can be added into this automatic controller development tools to make it smarter and more automatic. For example, the environment can support the developed technology for multi-thread and multi-core microprocessor to analysis and establish Instruction trace, and adjust the load balancing automatically. Or it can integrate the graphical programming allows users to program simpler and more intuitive.

This project aimed to create a simple open-source embedded graphical user interface library that could be used on more or less any microcontroller platform. The programming language was intended to be C++ for the GUI but as the project evolved C was chosen above C++. This was a decision based primarily on the fact that STM's development environment, STMCubeIDE, is less compatible with C++. The IDE offers great hardware support which in the end was more important than the advantages given by C++. The hardware used in this project was an STM32F469 microcontroller. It has an ARM CortexM4 processor core and 2 Mbyte of flash memory and 384 Kbytes of RAM. Wrapper functions for the Board Support Package, BSP, were written as a part of the library to allow easy access tothe BSP needed for the hardware configuration. The first part of the project goal was achieved, a simple GUI library was created. The resulting GUI library supports user interaction through buttons, it can display the current time andvisualizes given data in graphs. The graph function can display the data live, as a scatter plot, a bar plot and a line plot. The library also supports an alarm function that allows the user to decide what will happen after the alarm time is up. However, even though the GUI library was written to be device-independent, the product has not been tested on other platforms. For further development, this GUI library could be tested on another microcontroller. This would provide answers to how much software changes are needed to make the product as hardwareindependent as possible. To make the library lighter and faster, there is a possibility of optimizing the GUI core.

Mitochondria shape cytosolic Ca2+ (cCa2+) transients. Ca2+ entry into the mitochondria is driven by the highly negative mitochondrial membrane potential and through a highly selective channel, the Mitochondrial Calcium Uniporter (MCU). Mitochondrial Ca2+ (mCa2+) is utilized by the matrix dehydrogenases for maintaining cellular bioenergetics. The TCA cycle-derived NADH and FADH2 are mCa2+ dependent thus, feed into the electron transport chain (ETC) to generate ATP. Either loss of mCa2+ or metabolite uptake by the mitochondria results in a bioenergetic crisis and mitochondrial dysfunction. Reciprocally, sudden elevation of cCa2+ under conditions of stroke or ischemia/reperfusion injury (I/R) drives excessive mCa2+ overload that in turn leads to the opening of a large channel, the mitochondrial permeability transition pore (PTP) that triggers necrotic cell death. Thus, Ca2+ and metabolite equilibrium is essential to maintain a healthy mitochondrial pool. Our laboratory has previously showed that loss of mCa2+ uptake leads to decreased ATP generation and cell survival through autophagy. Although metabolite scarcity also results in similar reduction in ATP generation, the molecular mechanisms by which metabolites control mitochondrial ion homeostasis remain elusive. Deprivation of glucose or supplementation of mitochondrial pyruvate carrier (MPC) transport blocker UK5099 and or carnitine-dependent fatty acid blocker etomoxir triggered an increase in the expression of MICU1, a regulator of the mitochondrial calcium uniporter (MCU) but not the MCU core subunit. Consistently, either RNAi-mediated deletion of MPC isoforms or dominant negative human mutant MPC1 R97W showed significant induction of MICU1 protein abundance and inhibition of MCU-mediated mCa2+ uptake. Moreover, TCA cycle substrate-dependent MICU1 expression is under the control of EGR1 transcriptional regulation. Reciprocally, the MICU1 dependent inhibition of mCa2+ uptake exhibited lower NADH production and oxygen consumption and ATP production. The reduction of mitochondrial pyruvate by MPC knockdown is linked to higher production of mitochondrial ROS and elevated autophagy markers. These studies reveal an unexpected regulation of MCU-mediated mCa2+ flux machinery involving major TCA cycle substrate availability and possibly MICU1 to control cellular switch between glycolysis and oxidative phosphorylation. While mCa2+ is required for energy generation, sustained elevation of mCa2+ results in mitochondrial swelling and necrotic death. Hence, it was thought that preventing mCa2+ overload can be protective under conditions of elevated cCa2+. Contrary to this, mice knocked-out for MCU, that demonstrated no mCa2+ uptake and hence no mitochondrial swelling, however failed protect cells from I/R- mediated cell death. MCU-/- animals showed a similar infarct size comparable to that of control animals, suggesting that prevention of MCU-mediated mCa2+ overload alone is not sufficient to protect cells from Ca2+ -induced necrosis. The absence of mCa2+ entry revealed an elevation in the upstream cCa2+ transients in hepatocytes from MCUDHEP. Ultra-structural analysis of liver sections from MCU-/- (MCUDHEP) and MCUfl/fl animals revealed stark contrast in the shape of mitochondria: MCUfl/fl liver sections showed long and filamentous mitochondria (spaghetti-like) while MCUDHEP mitochondria were short and circular (donut-like). Furthermore, challenging MCUfl/fl and MCUDHEP hepatocytes with ionomycin caused a marked increase in cCa2+ and a simultaneous change in mitochondrial shape (from spaghetti to donut), a phenomenon we termed mitochondrial shape transition (MiST) that was independent of mitochondrial swelling. The cCa2+-mediated MiST is induced by an evolutionarily conserved mitochondrial surface EF-hand domain containing Miro1. Glutamate and Ca2+ -stress driven cCa2+ mobilization cause MiST in neurons that is suppressed by expression of Miro1 EF1 mutants. Miro1-dependent MiST is essential for autophagosome formation that is attenuated in cells harboring Miro1 EF1 mutants. Remarkably, loss of cCa2+ sensitization by Miro1 prevented MiST and mitigated autophagy. These results demonstrate that an interplay of ions and metabolites function in concert to regulate mitochondrial shape that in turn dictates the diverse mitochondrial processes from ATP generation to determining mechanisms of cell death. / Biomedical Sciences

Målet med detta examensarbete är att undersoka om det är möjligt att reducera energiförbrukningen i ett inbyggt system m.h.a. en Field Programmable Gate Array (FPGA) med låg effektförbrukning. Genom att flytta en del funktioner från systemets Micro Controller Unit (MCU) till en FPGA, hoppas uppdragsgivaren att systemets MCU kan ges mojligheten att gå över i ett mer energisnålt sömnlage under tillräckligt långa perioder. Rapporten beskriver utvecklingsarbetet från förstudie till implementeriung och test av framtagen design i en FPGA, AGLN250 fran Microsemi. Examensarbetet har visat att det ar fullt mojligt att reducera ett inbyggt systems effektförbrukning m.h.a. en FPGA. Dock måste man, p.g.a. en FPGA:s arkitektur, vara extra aktsam pa hur designen implementeras för att effektförbrukningen inte skall bli högre än förvantat. / The purpose of this thesis is to examine the possibility of reducing an embedded system's power consumption through the use of a low-power Field Programmable Gate Array (FPGA). The customer's hope was that by relocating some of the functionality from the system's Micro Controller Unit (MCU) to an FPGA, the system's MCU could remain in its most efficient power saving mode long enough to reduce the average power consumption to an acceptable level. This paper documents the development work, from initial background material studies up to the implementation and test of suggested designs in an actual FPGA, an AGLN250 from Microsemi. The thesis work has demonstrated that it is possible to reduce the power consumption of the customer's system by relocating some of the MCU functionality to an FPGA. However, due to an FPGA's architecture, care must be taken to ensure that the design is implemented in such a way that the signal activity is reduced as far as possible. Otherwise the power consumption might end up higher than expected.

En kostnadseffektiv, liten robotbil som är fjärrstyrd via Wi-Fi harutformats och testats för att möjliggöra inspektion och identifiering avpotentiella faror vid olycksplatser. Robotbilenär avsedd att användasför rekognosering och inspektion och kan bidra till att utforma enadekvat insatsplan. Hjulupphängning och hjul konstruerades medhjälp av en 3D-skrivare. Den färdiga robotbilen är utrustad medmikrokontrollern Raspberry Pi som har flera funktioner som gör denanvändbar i olika scenarier. Det finns en kamera som möjliggörfjärrinspektion av bilens omgivning. Utöver kameran finns det tresensorer som är kopplade till Raspberry Pi-enheten, nämligen engassensor för att upptäcka farliga gaser, en ultraljudssensor för attmäta avståndet till närmaste objekt och en temperatursensor för attmäta omgivningstemperaturen. Robotbilen använder enmotorstyrningsmodul för att styra bilens rörelse och två servomotorerför att möjliggöra att rotera kameran i vertikal och horisontell led.Robotbilens strömförsörjning kommer från ett batteri och tvåspänningsomvandlare används för att reglera spänningen tillmotorstyrningsmodulen och Raspberry Pi-enheten. Genom attintegrera dessa komponenter i en enda enhet och programmeraRaspberry Pi-enheten för att styra dem, kan robotbilen effektivt hjälpaatt undersöka och hantera potentiella faror. / A cost-effective small robot car that is remote-controlled via Wi-Fi hasbeen designed and tested for inspecting and identifying potentialhazards at accident sites. The robot car is intended for reconnaissanceand inspection purposes and can contribute to formulating anadequate action plan. Wheel suspension and wheels were constructedusing a 3D printer. The finished robot car is equipped with theRaspberry Pi microcontroller, which has severalfeatures that make ituseful in various scenarios. There is a camera that allows remoteinspection of the car's surroundings. In addition to the camera, thereare three sensors connected to the Raspberry Pi unit: a gas sensor todetect dangerous gases, an ultrasonic sensor to measure the distanceto the nearest object, and a temperature sensor to measure theambient temperature. The robot car uses a motor control module tocontrol its movement and two servo motors to enable the rotation ofthe camera in the vertical and horizontal directions. The robot car ispowered by a battery, and two voltage converters are used to regulatethe voltage to the motor control module and the Raspberry Pi unit. Byintegrating these components into a single unit and programming theRaspberry Pi unit to control them, the robot car can effectively assistin investigating and managing potential hazards.

Digital Twins (DTs) are nowadays gaining popularity as time-to-market is becoming a crucial factor to a product success. A twin replicates the behavior of a physical system in a virtual environment and the added value it provides depends on its accuracy and simulation time. In fact, a twin can be used to simulate corner cases in which damage can occur to the real system, or to run parallel tests to accelerate the development process. This work presents a DT for the VL53L0X Time-of-Flight (ToF) sensor developed with SystemC/Transaction Level Modeling (TLM)-2.0 standard. A generic method is introduced to investigate the minimal descriptive parameters to build empirical sensor models, in addition to how the use of different synchronization methods would affect the accuracy and simulation time of such sensors. The digital interface that connects the sensor to the Microcontroller Unit (MCU) has been developed using the sensor datasheet to mimic the Inter-Integrated Circuit (I2C) protocol. Results show that the real distance (measured by ray tracing in the simulator), the reflectance and the ambient light intensity can be used to mimic the output registers of the sensor. Furthermore, interpolating the fitting parameters can yield to results similar to that of a lookup method if the interpolation interval is small enough. The model has been integrated in two different co-simulations using different mechanical simulators with a plug-and-simulate easy-to-use Transmission Control Protocol (TCP) interface. The simulation time depends on the synchronization method used but no separability has been determined between the mechanical simulator and the TCP overhead. / Digitala tvillingar (DT) är idag alltmer populära eftersom time-to-market blir en avgörande faktor för en produkts framgång. En tvilling återskapar beteendet hos ett fysiskt system i en virtuell miljö och det mervärde den ger beror på dess noggrannhet och simuleringstid. En tvilling kan användas för att simulera hörnfall där skador kan uppstå på det verkliga systemet, eller för att köra parallella tester för att påskynda utvecklingsprocessen. Detta arbete presenterar en DT för VL53L0X ToF-sensorn som utvecklats med SystemC/TLM-2.0 standard. En generisk metod introduceras introduceras för att undersöka de minimala beskrivande parametrarna för att bygga empiriska sensor sensormodeller, utöver hur användningen av olika synkroniseringsmetoder skulle påverka noggrannheten och simuleringstiden för sådana sensorer? Det digitala gränssnittet som ansluter sensorn till mikrokontrollerenheten har utvecklats med hjälp av sensorns datablad för att efterlikna I2C-protokollet. Resultaten visar att det verkliga avståndet (uppmätt med strålspårning i simulatorn), reflektansen och den omgivande ljusintensiteten kan användas för att efterlikna sensorns utgångsregister. Dessutom kan interpolering av anpassningsparametrarna ge resultat som liknar dem från en uppslagsmetod om interpoleringsintervallet är tillräckligt litet. Modellen har integrerats i två olika samsimuleringar med hjälp av olika mekaniska simulatorer med ett lättanvänt TCP-gränssnitt för plug-and-simulate. Simuleringstiden berodde på vilken synkroniseringsmetod som användes, men ingen separerbarhet har fastställts mellan den mekaniska simulatorn och TCP overhead-gränssnittet.