18 research outputs found

    Herpes simplex encephalitis is linked with selective mitochondrial damage; a post-mortem and in vitro study

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    Herpes simplex virus type-1 (HSV-1) encephalitis (HSE) is the most commonly diagnosed cause of viral encephalitis in western countries. Despite antiviral treatment, HSE remains a devastating disease with high morbidity and mortality. Improved understanding of pathogenesis may lead to more effective therapies. Mitochondrial damage has been reported during HSV infection in vitro. However, whether it occurs in the human brain and whether this contributes to the pathogenesis has not been fully explored. Minocycline, an antibiotic, has been reported to protect mitochondria and limit brain damage. Minocycline has not been studied in HSV infection. In the first genome-wide transcriptomic study of post-mortem human HSE brain tissue, we demonstrated a highly preferential reduction in mitochondrial genome (MtDNA) encoded transcripts in HSE cases (n = 3) compared to controls (n = 5). Brain tissue exhibited a significant inverse correlation for immunostaining between cytochrome c oxidase subunit 1 (CO1), a MtDNA encoded enzyme subunit, and HSV-1; with lower abundance for mitochondrial protein in regions where HSV-1 was abundant. Preferential loss of mitochondrial function, among MtDNA encoded components, was confirmed using an in vitro primary human astrocyte HSV-1 infection model. Dysfunction of cytochrome c oxidase (CO), a mitochondrial enzyme composed predominantly of MtDNA encoded subunits, preceded that of succinate dehydrogenase (composed entirely of nuclear encoded subunits). Minocycline treated astrocytes exhibited higher CO1 transcript abundance, sustained CO activity and cell viability compared to non-treated astrocytes. Based on observations from HSE patient tissue, this study highlights mitochondrial damage as a critical and early event during HSV-1 infection. We demonstrate minocycline preserves mitochondrial function and cell viability during HSV-1 infection. Minocycline, and mitochondrial protection, offers a novel adjunctive therapeutic approach for limiting brain cell damage and potentially improving outcome among HSE patients

    Analysis of mass parameters influence on truck stability, based on road testing of vehicle model in small scale

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    Praca przedstawia analiz臋 wp艂ywu po艂o偶enia 艣rodka masy i jej rozk艂adu na stateczno艣膰 samochodu ci臋偶arowego. Z uwagi na znaczny koszt bada艅 i niebezpiecze艅stwo przewr贸cenia pojazdu starano si臋 odwzorowa膰 zachowanie si臋 rzeczywistego pojazdu, wykorzystuj膮c podobie艅stwo a badania przeprowadzono na mobilnym modelu pojazdu. W pracy przedstawiono analiz臋 wp艂ywu takich parametr贸w masowy moment bezw艂adno艣ci wzgl臋dem osi wzd艂u偶nej i pionowej przy zachowaniu po艂o偶enia 艣rodka masy pojazdu. Analiz臋 przeprowadzono w oparciu o pr贸by drogowe. Przedstawiono por贸wnanie z wynik贸w dla r贸偶nych rozk艂ad贸w mas.The paper presents an analysis of influence of the center of mass and its distribution on the truck stability. With the considerable cost of research and the danger of rollover the vehicle tried to demonstrate the behavior of the real vehicle, using a similar studies carried out on a mobile vehicle model. The paper presents analysis of the influence of parameters such mass moment of inertia about its longitudinal axis and a vertical position while keeping the center of mass of the vehicle. The analysis was based on road tests. Thera are showed comparison of results for different distributions of the masses

    Wykorzystanie mobilnego modelu pojazdu do analizy stateczno艣ci poprzecznej samochodu ci臋偶arowego

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    This paper presents the results of an attempt to transfer resistance to the side overturning of the vehicle to the mobile vehicle in the scale of ~ 1:5 on the real vehicle. Due to the substantial cost of testing and the danger of rollover real vehicle attempt was made to reproduce the behaviour of the vehicle, using the conditions of similarity. The paper presents methods of risk detection and control algorithms in stability systems equipped with a safety feature to prevent rollover. The analysis was based on the tests carried out at research training ground. Shows the results of tests on a real and a mobile smaller scale vehicles, and the values of obtained rollover risk indicators.Praca przedstawia pr贸b臋 przeniesienia wynik贸w bada艅 odporno艣ci na przewr贸cenie pojazdu na bok z mobilnego modelu pojazdu w skali ~1:5 na pojazd rzeczywisty. Z uwagi na znaczny koszt bada艅 i niebezpiecze艅stwo przewr贸cenia pojazdu rzeczywistego starano si臋 odwzorowa膰 zachowanie si臋 pojazdu, wykorzystuj膮c warunki podobie艅stwa. W pracy przedstawiono sposoby detekcji zagro偶enia oraz algorytmy sterowania uk艂ad贸w stabilizacji toru jazdy wyposa偶onych w funkcj臋 zabezpieczaj膮c膮 przed przewr贸ceniem. Analiz臋 przeprowadzono w oparciu o pr贸by poligonowe. Przedstawiono wyniki bada艅 pojazdu rzeczywistego i mobilnego modelu w mniejszej skali oraz uzyskane warto艣ci wska藕nik贸w zagro偶enia przewr贸ceniem pojazdu

    Influence of the suspension faults on the car motion stability - comparison and analysis of test results

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    W artykule przedstawiono wyniki bada艅 drogowych wp艂ywu niesprawno艣ci uk艂adu jezdnego na kierowalno艣膰 i stateczno艣膰 ruchu pojazdu podczas manewr贸w rozp臋dzania i hamowania. Analiza dotyczy艂a toru jazdy, si艂 i moment贸w na kole kierowniczym oraz k膮t贸w skr臋tu k贸艂 przednich. Do oceny zachowania si臋 pojazdu wykorzystano r贸wnie偶 parametr nazwany wysi艂kiem kierowcy. Wp艂yw badanych niesprawno艣ci na momenty si艂 i k膮ty por贸wnywano ze zbadanymi odpowiednimi wielko艣ciami dla pojazdu sprawnego.The paper presents the results of analysis and vehicle research during acceleration and braking. The vehicle was tested with different faults of front and rear suspension. The analysis included path, moments and forces in suspensions and steering system. Numerical analysis were done for similar faults. Driver effort was determined too

    Utilization of the car model to the analysis of the vehicle movement after the curvilinear track

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    Badania stateczno艣ci samochod贸w ci臋偶arowych, szczeg贸lnie podczas wykonywania manewr贸w skr臋tu, stwarzaj膮 niebezpiecze艅stwo wywr贸cenia pojazdu. Aby temu zapobiec stosuje si臋 specjalne belki zabezpieczaj膮ce przed wywrotem lub d膮偶y si臋 do wyznaczania stateczno艣ci metodami obliczeniowymi lub przy wykorzystaniu modeli pojazd贸w. Przedstawiona praca stanowi opis przeprowadzonych pr贸b modelu pojazdu a tak偶e por贸wnanie ich zachowania si臋 z ruchem rzeczywistych pojazd贸w. Poni偶ej przedstawiono por贸wnanie zachowania si臋 modelu i pojazd贸w podczas jazdy po okr臋gu.The testing of the stability of large weight vehicles, particularly while executing the manoeuvres of the turn, creates the emergency of the overturn of the vehicle. To prevent this, he complies special anti-roll beams mounted to vehicles or one proceed to determine stability using computational methods. We can also carry over tests on models of vehicles. The introduced work makes up the description of the carried over tests of the model of the vehicle and also the comparison of their behaviour oneself with the motion of real vehicles. Below is presented the comparison of behaviour presented truck model and vehicle during the drive after the circle track

    Study of the vehicle dynamics with the application of scale models

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    W pracy przedstawiono pr贸b臋 wykorzystania modeli fizycznych pojazd贸w w skali do analizy dynamiki ruchu rzeczywistych pojazd贸w. Parametry geometryczne modelu oraz kinematyk臋 i dynamik臋 ruchu okre艣lono wykorzystuj膮c teori臋 podobie艅stwa i analiz臋 wymiarow膮. Om贸wiono problemy zwi膮zane z konstruowaniem i sterowaniem modeli. Zagadnienia dotycz膮ce stateczno艣ci ruchu pojazdu wi膮偶膮 si臋 z jego parametrami charakterystycznymi takimi jak: rozk艂ad mas na poszczeg贸lne osie, wysoko艣膰 艣rodka ci臋偶ko艣ci, momenty bezw艂adno艣ci zar贸wno ca艂ego pojazdu jak i masy resorowanej oraz sztywno艣膰 i t艂umienie drga艅 nadwozia a tak偶e po艂o偶enie osi przechy艂u i parametry charakterystyczne opon. Osobny problem stanowi sterowanie modelu, zw艂oka czasowa i powtarzalno艣膰 wykonywanych manewr贸w. Pomimo problem贸w konstrukcyjnych wyniki bada艅 s膮 bardzo obiecuj膮ce i pozwalaj膮 na przeniesienie wynik贸w pomiar贸w z mobilnego modelu na pojazd rzeczywisty. Co oznacza, 偶e w przypadku pojazd贸w, produkowanych jednostkowo, b膮d藕 pojazd贸w, kt贸rych bada艅 nie da si臋 przeprowadzi膰, mo偶na je zast膮pi膰 badaniami i pomiarami wykonanymi na modelu w skali.The paper presents an attempt to use physical models of vehicles on a scale to analyze the dynamics of the real motion of vehicles. Geometric parameters of the model and the kinematics and dynamics of motion defined using the theory of similarity and dimensional analysis. The problems associated with the construction and control models was presented. Considerations for stability of the vehicle motion connected with its characteristic parameters such as weight distribution on each axis, the height of the center of mass, moments of inertia of both the vehicle and the sprung mass and the stiffness and damping of the body as well as the position of the roll axis and the characteristic parameters of the tire. A separate problem is the control of model, time delay and repetition performed maneuvers. Despite the structural design results are very promising and allow for the transfer of the results of tests of the mobile model on a real vehicle. This means that in the case of vehicles manufactured individually, or vehicle, where tests can not be done, it may be replaced by tests and measurements made on the scale model

    The influence of vehicle body roll angle on the motion stability and maneuverability of the vehicle

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    The article discusses the impact of design solutions of vehicle suspensions into angles of body roll. It was shown which type of suspensions is better from this point of view. There were examined the dependence of the suspensions parameters on the vehicle body roll angle. The influence of camber angle on the force transmitted to the tire contact with the road surface was analysed. The lateral forces were measured on the test stand. There was tested dependency of lateral forces from the sideslip angle for different angles of camber. Was analysed change of lateral forces generated by camber angle on the vehicle which was made on a scale ~ 1:5 during tests carried out on the testing track. For this purpose, two tests have been selected: first one allowing the measurement in steady motion conditions, the second one with dynamic change of direction of vehicle motion. The graphs show the effect of camber angles on the controllability and stability of the vehicle motion

    Make use of the friction coefficient during braking the vehicle

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    In this publication is presented use the tyre-road friction during vehicle braking. Results presented in this publication are based on the road tests of the vehicle equipped in the anti-lock brake system (ABS). Two kinds of tests applied were carried out - the road tests of vehicle making the manoeuvre of braking on the straight section of the road and on the curve of the road. The braking forces and the friction coefficients for the individual wheels of the vehicle were defined on the basis of road tests, including the border values of the friction coefficient.W publikacji przedstawiono zagadnienie wykorzystania przyczepno艣ci opony do nawierzchni jezdni podczas hamowania. Wyniki prezentowane w publikacji oparto na badaniach drogowych pojazdu osobowego wyposa偶onego w uk艂ad zapobiegaj膮cy blokowaniu k贸艂. Przeprowadzono dwa rodzaje pr贸b stosowanych do badania wykorzystania przyczepno艣ci - badania pojazdu wykonuj膮cego manewr hamowania na prostoliniowym odcinku drogi oraz na 艂uku drogi. Na podstawie bada艅 okre艣lono si艂y hamowania oraz wsp贸艂czynniki przyczepno艣ci dla poszczeg贸lnych k贸艂 pojazdu, w tym warto艣ci graniczne wsp贸艂czynnika przyczepno艣ci

    Measurement of the vehicle torsional stiffness

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    Pojazdy z wysoko po艂o偶onym 艣rodkiem masy maj膮 tendencj臋 do wywracania si臋, szczeg贸lnie podczas wykonywania gwa艂townych manewr贸w skr臋tu. Na parametry okre艣laj膮ce stateczno艣膰 boczn膮 pojazdu ma wp艂yw wiele czynnik贸w mi臋dzy innymi: po艂o偶enie 艣rodka masy, sztywno艣膰 zawieszenia, moment bezw艂adno艣ci oraz parametry ruchu pojazdu. Prowadzone w Katedrze Silnik贸w Spalinowych i Pojazd贸w badania pozwalaj膮 na okre艣lenie wp艂ywu czynnik贸w konstrukcyjnych na stateczno艣膰 samochod贸w ci臋偶arowych. Podobne zagadnienia dotycz膮 samochod贸w osobowych, z t膮 r贸偶nic膮, 偶e tu niebezpiecze艅stwo przewr贸cenia pojazdu jest mniejsze. Przedstawiona praca stanowi opis przeprowadzonych bada艅 pojazdu oraz sposobu wyznaczania sztywno艣ci k膮towej zawiesze艅. Sztywno艣膰 ta pozwala na okre艣lenie granicznych warunk贸w, przy kt贸rych dojdzie do przewr贸cenia pojazdu.Vehicles with high location of the centre of mass tend to roll over, particularly while executing the sudden turn manoeuvres. Many factors influence the parameters determining the vehicle side stability, such as: the location of the centre of the mass, the suspension stiffness, the moment of inertia of a car body and the vehicle motion parameters. Investigations conducted in the Department of Combustion Engines and Vehicles makes it possible to determine the influence of construction factors on the truck stability. Similar problems refer to automobiles, however, the probability of overturn is smaller in that case. The paper presents the performed investigations of the vehicle and the procedure for determining the torsional stiffness of suspensions. The automobile suspensions cause that during the vehicle movement in the after-effect of the forces operation, the body leans and the centre of the mass moves. The change of the centre of the mass position causes lowering the critical parameters for which there occurs the vehicle rollover. The angle of the body tilting is dependent on the suspension stiffness. The proportionality coefficient between the angle of the car body inclination and the reactionary moment of the resilience of suspen-sions is called the torsional stiffness of suspensions. Its reverse is the vehicle rollover threshold. The value of the torsional stiffness of suspensions k? will be uniform in the case of the drive steady conditions. During executions of sudden manoeuvres damping forces in suspensions will cause the change of their characteristics. This will enlarge the effective stiffness. Additional springy units cooperate at large angles of the car body inclination and change the suspension characteristic. On the basis of the measurements taken and analyses performed one can state that: - it is possible to define the vehicle suspension torsional stiffness on a basis of road tests, - the measurement accuracy is determined by many factors such as: the investigated track surface irregularity, deviation from the given drive velocity, deviation from the given steering wheel angle, change of the schedule of the weight on wheels, change of the friction coefficient between wheels and road, etc.- the determined stiffness values oscillate around the average value which was assumed to be the suspension torsional stiffness value of the tested vehicle.The torsional stiffness obtained from the suspension investigations can be used for calculations of the critical velocity of possible vehicle rollover

    Movable model of a car to dynamic testing

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    W pracy przedstawiono opis zdalnie sterowanego modelu samochodu ci臋偶arowego, kt贸ry przystosowano do bada艅 dynamiki ruchu. Konstrukcja pojazdu odzwierciedla wszystkie wa偶niejsze zespo艂y uk艂adu przeniesienia nap臋du, zawiesze艅 i uk艂adu kierowniczego. Dzi臋ki odpowiedniej budowie mo偶na ustala膰 po艂o偶enie 艣rodka masy. Model wyposa偶ono w czujniki przyspiesze艅 x-y, kt贸rych wskazania s膮 przesy艂ane telemetrycznie do przeno艣nego komputera. W publikacji przedstawiono wyniki bada艅 gwa艂townego skr臋tu na p艂aszczy藕nie i jazdy po okr臋gu na p艂askiej nawierzchni o sta艂ym nachyleniu.A remote controlled model of a car is described in the paper. The model can be used to preliminary simulating investigations of the car movement. The vehicle model simulates all the most important components of the transmission, suspension and steering system. Owing to a suitable structure it is possible to change the position of the vehicle mass center. The model is equipped with the indicator of the danger of overturning and the sensors of the longitudinal and transverse accelerations, whose read-outs are transmitted telemetrically to a portable computer. It was fixed that the indicator begins its function when the established margin of accelerations is crossed. The modulation of acoustic and optical indicator signals increases with approaching to the limit of overturn of the vehicle. Authors analyze the matter of possible faults of registered movement parameters of the car as can mainly appear from the lack of the similarity of the stiffness of tires, suspensions and the bearing constructions of the vehicle. However, because of very high investigation costs of real car the model investigation can be applied instead of preliminary investigations of real object. Investigations of the indicator of exceeding the limiting lateral accelerations worked out by authors are introduced in the paper. The crossing of acceleration limit can cause the overturning the vehicle. The paper presents test results of sharp turn on the horizontal plane and on circular path drive on a flat surface with constant slope. It was showed in the paper that one can lead functional dynamic investigations on the mobile car model in the range of preliminary investigations
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