A dohányzási szokásokat befolyásoló környezeti tényezők egy- és kétpetéjű ikrek körében

Introduction: Smoking habits are influenced by environmental (family, friends) and psychologic factors. Aim: To investigate environmental factors which influence the smoking habits of monozygotic and dizygotic twins. Method: 45 monozygotic and 23 dizygotic twin pairs (age 35+/-16 years) completed a questionnaire. Results: Maternal non-smoking decreases the risk of smoking of the twin children by 53%, while this effect accounts for 49% by the father. Dizygotic twins are more influenced by parents (70%) than monozygotics (31-36%). If the twin or non-twin sibling does not smoke, the risk that the twin individual starts smoking, is decreased by 86% both in monozygotic and dizygotic twins. If an individual smoking is present in the fraternity and he or she does not attempt to quit, the risk of smoking increases 8.3-fold. The role of fraternity is more important in males and youth. Conclusions: The parents' and the siblings' exemplary behaviour helps to avoid smoking initiation of young twins. Orv. Hetil., 2013, 154, 978-984

Evaluation of externally heated pulsed MPD thruster cathodes

Recent interest in solar electric orbit transfer vehicles (SEOTV's) has prompted a reevaluation of pulsed magnetoplasmadynamic (MPD) thruster systems due to their ease of power scaling and reduced test facility requirements. In this work the use of externally heated cathodes was examined in order to extend the lifetime of these thrusters to the 1000 to 3000 hours required for SEOTV missions. A pulsed MPD thruster test facility was assembled, including a pulse-forming network (PFN), ignitor supply and propellant feed system. Results of cold cathode tests used to validate the facility, PFN, and propellant feed system design are presented, as well as a preliminary evaluation of externally heated impregnated tungsten cathodes. The cold cathode thruster was operated on both argon and nitrogen propellants at peak discharge power levels up to 300 kW. The results confirmed proper operation of the pulsed thruster test facility, and indicated that large amounts of gas were evolved from the BaO-CaO-Al2O3 cathodes during activation. Comparison of the expected space charge limited current with the measured vacuum current when using the heated cathode indicate that either that a large temperature difference existed between the heater and the cathode or that the surface work function was higher than expected

Low power pulsed MPD thruster system analysis and applications

Pulsed magnetoplasmadynamic (MPD) thruster systems were analyzed for application to solar-electric orbit transfer vehicles at power levels ranging from 10 to 40 kW. Potential system level benefits of pulsed propulsion technology include ease of power scaling without thruster performance changes, improved transportability from low power flight experiments to operational systems, and reduced ground qualification costs. Required pulsed propulsion system components include a pulsed applied-field MPD thruster, a pulse-forming network, a charge control unit, a cathode heater supply, and high speed valves. Mass estimates were obtained for each propulsion subsystem and spacecraft component using off-the-shelf technology whenever possible. Results indicate that for payloads of 1000 and 2000 kg pulsed MPD thrusters can reduce launch mass by between 1000 and 2500 kg over those achievable with hydrogen arcjets, which can be used to reduce launch vehicle class and the associated launch cost. While the achievable mass savings depends on the trip time allowed for the mission, cases are shown in which the launch vehicle required for a mission is decreased from an Atlas IIAS to an Atlas I or Delta 7920

Very near-field plume investigation of the D55

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76343/1/AIAA-1997-3062-753.pd

Sensitivity of hollow cathode performance to design and operating parameters

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76435/1/AIAA-1999-2576-299.pd

The D-100 performance and plume characterization on krypton

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76487/1/AIAA-1996-2969-208.pd

Wear Testing and Analysis of Ion Engine Discharge Cathode Keeper

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77116/1/AIAA-4441-635.pd

Near-field investigation of ions emitted from a hollow cathode assembly operating at low-power

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76514/1/AIAA-1998-3658-652.pd

Momordica charantia (bitter melon) attenuates high-fat diet-associated oxidative stress and neuroinflammation

<p>Abstract</p> <p>Background</p> <p>The rising epidemic of obesity is associated with cognitive decline and is considered as one of the major risk factors for neurodegenerative diseases. Neuroinflammation is a critical component in the progression of several neurological and neurodegenerative diseases. Increased metabolic flux to the brain during overnutrition and obesity can orchestrate stress response, blood-brain barrier (BBB) disruption, recruitment of inflammatory immune cells from peripheral blood and microglial cells activation leading to neuroinflammation. The lack of an effective treatment for obesity-associated brain dysfunction may have far-reaching public health ramifications, urgently necessitating the identification of appropriate preventive and therapeutic strategies. The objective of our study was to investigate the neuroprotective effects of <it>Momordica charantia </it>(bitter melon) on high-fat diet (HFD)-associated BBB disruption, stress and neuroinflammatory cytokines.</p> <p>Methods</p> <p>C57BL/6 female mice were fed HFD with and without bitter melon (BM) for 16 weeks. BBB disruption was analyzed using Evans blue dye. Phosphate-buffered saline (PBS) perfused brains were analyzed for neuroinflammatory markers such as interleukin-22 (IL-22), IL-17R, IL-16, NF-κB1, and glial cells activation markers such as Iba1, CD11b, GFAP and S100β. Additionally, antioxidant enzymes, ER-stress proteins, and stress-resistant transcription factors, sirtuin 1 (Sirt1) and forkhead box class O transcription factor (FoxO) were analyzed using microarray, quantitative real-time RT-PCR, western immunoblotting and enzymatic assays. Systemic inflammation was analyzed using cytokine antibody array.</p> <p>Results</p> <p>BM ameliorated HFD-associated changes in BBB permeability as evident by reduced leakage of Evans blue dye. HFD-induced glial cells activation and expression of neuroinflammatory markers such as NF-κB1, IL-16, IL-22 as well as IL-17R were normalized in the brains of mice supplemented with BM. Similarly, HFD-induced brain oxidative stress was significantly reduced by BM supplementation with a concomitant reduction in FoxO, normalization of Sirt1 protein expression and up-regulation of Sirt3 mRNA expression. Furthermore, plasma antioxidant enzymes and pro-inflammatory cytokines were also normalized in mice fed HFD with BM as compared to HFD-fed mice.</p> <p>Conclusions</p> <p>Functional foods such as BM offer a unique therapeutic strategy to improve obesity-associated peripheral inflammation and neuroinflammation.</p