Alapvető szimmetriák vizsgálata antiprotonokkal = Study of fundamental symmetries using antiprotons

Tevékenységünk a CERN Antiproton-lassítója melletti ASACUSA együttműködés különböző kísérleteihez kapcsolódik, főként az anyag és antianyag egyenértékűségét kimondó CPT-invariancia kísérleti ellenőrzésére. Hangolható lézerrel átmenetet stimulálunk antiprotonos héliumatom hosszú és rövid élettartamú állapotai között, az átmeneti energiából meghatározzuk az antiproton és az elektron tömegének hányadosát. A méréseinket egészen ritka és hideg gázban végezve, a lézerfrekvenciát frekvenciafésűvel stabilizálva, az atomi mozgás miatti Doppler-hatást kétfotonos gerjesztéssel csökkentve, a protonéhoz közeli pontosságot értünk el az antiproton tömegének meghatározásában. A lézer-mikrohullám-lézer hármas rezonancia módszerével meghatároztuk az antiproton mágneses momentumát hélium-4 és hélium-3 atomokban és az elméletivel egyező spektrumokat kaptunk. Prototípust építettünk az antihidrogén előállítására szolgáló kétmódusú Paul-csapdához és megépítettük az antihidrogén képződését ellenőrző detektorrendszerünket. Kisenergiájú antiproton és hidrogén molekula ütközésében meghatároztuk az egyszeres ionizációs hatáskeresztmetszeteket és elméleti számításokat végeztünk egyszeresen és kétszeresen differenciális hatáskeresztmetszetekre antiproton és hélium ütközéseiben, valamint hidrogén- és vízmolekula ionizációjára polarizált lézertérben. Megmértük az ionvezetés hőmérsékletfüggését kapillárisokban és rámutattunk, hogy kis energián rugalmas ütközés, nagyobbakon a Coulomb-taszítás dominál. | Our activity is connected to the experiments of the ASACUSA collaboration at the Antiproton Decelerator of CERN, mainly to the tests of CPT invariance, stating the equivalence of matter and antimatter. Using tunable lasers to stimulate transitions between short- and long-lived states in antiprotonic helium atoms, from the transition energies we determine the antiproton-to-electron mass ratio. Performing the measurements in low-pressure cold gas, stabilising the laser tune using a frequency comb and reducing the Doppler broadening from atomic motion using two-photon spectroscopy we managed to reach a precision of determining to antiproton mass close to that of the proton. Using a laser-microwave-laser triple resonance technique we have measured the magnetic moment of the antiproton in He-4 and He-3 atoms in agreement with the theoretical predictions. We have built a prototype of a two-tone Paul-trap for antihydrogen formation and also a detector system for testing antihydrogen annihilation. We have measured single ionization cross sections for collisions of low-energy antiprotons with hydrogen molecules and calculated singly and doubly differential cross sections for collisons of antiprotons with helium and also for the ionization of hydrogen and water molecules in a polarized laser field. Measured the temperature dependence of ionic conductivity in capillaries and showed that at low energies elastic collisions whereas at higher ones Coulomb repulsion dominate

Postconditioning in major vascular surgery: prevention of renal failure

This study investigates teachers in the Swedish ten-year compulsory school who use ICT(Information and communication technology) in their classroom practice. It poses andgives answers to questions about what is contributing most to explain why they choose touse computers and information technology in their work with students/pupils and usesmultiple regression analysis in order to investigate the best pattern of predictive variables.A significant model emerged suggesting that teachers using ICT with students wereinterested in changing their classroom practice. They also felt self-efficacious in usingcomputers in education and they have positive attitudes toward using ICT in education.The present investigation differs from other studies in that it examines teachers whoalready are using technology in their classroom practice and it could be seen as a buildingblock in the development of knowledge about how teachers can become more competentand confident in using ICT in their pedagogical work in classroom practice

Levosimendan Administration in Limb Ischemia: Multicomponent Signaling Serving Kidney Protection

AIMS AND OBJECTIVES: Acute renal failure is a severe complication of lower extremity major arterial reconstructions, which could even be fatal. Levosimendan is a dual-acting positive inotropic and vasodilatory agent, which is suspected to have protective effects against cardiac ischemia. However, there is no data available on lower limb or remote organ ischemic injuries therefore the aim of the study was to investigate the effect of levosimendan on lower limb ischemia-reperfusion injury and the corollary renal dysfunction. METHODS: Male Wistar rats underwent 180 min bilateral lower limb ischemia followed by 4 or 24 hours of reperfusion. Intravenous Levosimendan was administered continuously (0.2mug/bwkg/min) throughout the whole course of ischemia and the first 3h of reperfusion. Results were compared with sham-operated and ischemia-reperfusion groups. Hemodynamic monitoring was performed by invasive arterial blood pressure measurement. Kidney and lower limb muscle microcirculation was registered by a laser Doppler flowmeter. After 4h and 24h of reperfusion, serum, urine and histological samples were collected. RESULTS: Systemic hemodynamic parameters and microcirculation of kidney and the lower limb significantly improved in the Levosimendan treated group. Muscle viability was significantly preserved 4 and 24 hours after reperfusion. At the same time, renal functional laboratory tests and kidney histology demonstrated significantly less expressive kidney injury in Levosimendan groups. TNF-alpha levels were significantly less elevated in the Levosimendan group 4 hours after reperfusion. CONCLUSION: The results claim a protective role for Levosimendan administration during major vascular surgeries to prevent renal complications

Attenuation of Skeletal Muscle and Renal Injury to the Lower Limb following Ischemia-Reperfusion Using mPTP Inhibitor NIM-811.

INTRODUCTION: Operation on the infrarenal aorta and large arteries of the lower extremities may cause rhabdomyolysis of the skeletal muscle, which in turn may induce remote kidney injury. NIM-811 (N-metyl-4-isoleucine-cyclosporine) is a mitochondria specific drug, which can prevent ischemic-reperfusion (IR) injury, by inhibiting mitochondrial permeability transition pores (mPTP). OBJECTIVES: Our aim was to reduce damages in the skeletal muscle and the kidney after IR of the lower limb with NIM-811. MATERIALS AND METHODS: Wistar rats underwent 180 minutes of bilateral lower limb ischemia and 240 minutes of reperfusion. Four animal groups were formed called Sham (receiving vehicle and sham surgery), NIM-Sham (receiving NIM-811 and sham surgery), IR (receiving vehicle and surgery), and NIM-IR (receiving NIM-811 and surgery). Serum, urine and histological samples were taken at the end of reperfusion. NADH-tetrazolium staining, muscle Wet/Dry (W/D) ratio calculations, laser Doppler-flowmetry (LDF) and mean arterial pressure (MAP) monitoring were performed. Renal peroxynitrite concentration, serum TNF-alpha and IL-6 levels were measured. RESULTS: Less significant histopathological changes were observable in the NIM-IR group as compared with the IR group. Serum K+ and necroenzyme levels were significantly lower in the NIM-IR group than in the IR group (LDH: p<0.001; CK: p<0.001; K+: p = 0.017). Muscle mitochondrial viability proved to be significantly higher (p = 0.001) and renal function parameters were significantly better (creatinine: p = 0.016; FENa: p<0.001) in the NIM-IR group in comparison to the IR group. Serum TNF-alpha and IL-6 levels were significantly lower (TNF-alpha: p = 0.003, IL-6: p = 0.040) as well as W/D ratio and peroxynitrite concentration were significantly lower (p = 0.014; p<0.001) in the NIM-IR group than in the IR group. CONCLUSION: NIM-811 could have the potential of reducing rhabdomyolysis and impairment of the kidney after lower limb IR injury

Expression and In Vivo Rescue of Human ABCC6 Disease-Causing Mutants in Mouse Liver

Loss-of-function mutations in ABCC6 can cause chronic or acute forms of dystrophic mineralization described in disease models such as pseudoxanthoma elasticum (OMIM 26480) in human and dystrophic cardiac calcification in mice. The ABCC6 protein is a large membrane-embedded organic anion transporter primarily found in the plasma membrane of hepatocytes. We have established a complex experimental strategy to determine the structural and functional consequences of disease-causing mutations in the human ABCC6. The major aim of our study was to identify mutants with preserved transport activity but failure in intracellular targeting. Five missense mutations were investigated: R1138Q, V1298F, R1314W, G1321S and R1339C. Using in vitro assays, we have identified two variants; R1138Q and R1314W that retained significant transport activity. All mutants were transiently expressed in vivo, in mouse liver via hydrodynamic tail vein injections. The inactive V1298F was the only mutant that showed normal cellular localization in liver hepatocytes while the other mutants showed mostly intracellular accumulation indicating abnormal trafficking. As both R1138Q and R1314W displayed endoplasmic reticulum localization, we tested whether 4-phenylbutyrate (4-PBA), a drug approved for clinical use, could restore their intracellular trafficking to the plasma membrane in MDCKII and mouse liver. The cellular localization of R1314W was significantly improved by 4-PBA treatment, thus potentially rescuing its physiological function. Our work demonstrates the feasibility of the in vivo rescue of cellular maturation of some ABCC6 mutants in physiological conditions very similar to the biology of the fully differentiated human liver and could have future human therapeutic application

Discutindo a educação ambiental no cotidiano escolar: desenvolvimento de projetos na escola formação inicial e continuada de professores

A presente pesquisa buscou discutir como a Educação Ambiental (EA) vem sendo trabalhada, no Ensino Fundamental e como os docentes desta escola compreendem e vem inserindo a EA no cotidiano escolar., em uma escola estadual do município de Tangará da Serra/MT, Brasil. Para tanto, realizou-se entrevistas com os professores que fazem parte de um projeto interdisciplinar de EA na escola pesquisada. Verificou-se que o projeto da escola não vem conseguindo alcançar os objetivos propostos por: desconhecimento do mesmo, pelos professores; formação deficiente dos professores, não entendimento da EA como processo de ensino-aprendizagem, falta de recursos didáticos, planejamento inadequado das atividades. A partir dessa constatação, procurou-se debater a impossibilidade de tratar do tema fora do trabalho interdisciplinar, bem como, e principalmente, a importância de um estudo mais aprofundado de EA, vinculando teoria e prática, tanto na formação docente, como em projetos escolares, a fim de fugir do tradicional vínculo “EA e ecologia, lixo e horta”.Facultad de Humanidades y Ciencias de la Educació