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Sample records for generator mechanical smoke

  1. Generator, mechanical, smoke: For dual-purpose unit, XM56, Yuma Proving Ground, Yuma, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Driver, C.J.; Ligotke, M.W.; Moore, E.B. Jr. (Pacific Northwest Lab., Richland, WA (United States)); Bowers, J.F. (Dugway Proving Ground, UT (United States))

    1991-10-01

    The US Army Chemical Research, Development and Engineering Center (CRDEC) is planning to perform a field test of the XM56 smoke generator at the US Army Yuma Proving Ground (YPG), Arizona. The XM56, enabling the use of fog oil in combination with other materials, such as graphite flakes, is part of an effort to improve the efficiency of smoke generation and to extend the effectiveness of the resulting obscurant cloud to include the infrared spectrum. The plan field operation includes a road test and concurrent smoke- generation trials. Three M1037 vehicles with operation XM56 generators will be road-tested for 100 h. Smoke will be generated for 30 min from a single stationary XM56 four times during the road test, resulting in a total of 120 min of smoke generation. The total aerial release of obscurant materials during this test is expected to be 556 kg (1,220 lb) of fog oil and 547 kg (1,200 lb) of graphite flakes. This environmental assessment has evaluated the consequences of the proposed action. Air concentrations and surface deposition levels were estimated using an atmospheric dispersion model. Degradation of fog oil and incorporation of graphite in the soil column will limit the residual impacts of the planned action. No significant impacts to air, water, and soil quality are anticipated. risks to the environment posed by the proposed action were determined to be minimal or below levels previously found to pose measurable impacts. Cultural resources are present on YPG and have been identified in adjacent areas; therefore, off-road activities should be preceded by a cultural resource survey. A Finding of No Significant Impact is recommended. 61 refs., 1 fig.

  2. Acetyl radical generation in cigarette smoke: Quantification and simulations

    Science.gov (United States)

    Hu, Na; Green, Sarah A.

    2014-10-01

    Free radicals are present in cigarette smoke and can have a negative effect on human health. However, little is known about their formation mechanisms. Acetyl radicals were quantified in tobacco smoke and mechanisms for their generation were investigated by computer simulations. Acetyl radicals were trapped from the gas phase using 3-amino-2, 2, 5, 5-tetramethyl-proxyl (3AP) on solid support to form stable 3AP adducts for later analysis by high-performance liquid chromatography (HPLC), mass spectrometry/tandem mass spectrometry (MS-MS/MS) and liquid chromatography-mass spectrometry (LC-MS). Simulations were performed using the Master Chemical Mechanism (MCM). A range of 10-150 nmol/cigarette of acetyl radical was measured from gas phase tobacco smoke of both commercial and research cigarettes under several different smoking conditions. More radicals were detected from the puff smoking method compared to continuous flow sampling. Approximately twice as many acetyl radicals were trapped when a glass fiber particle filter (GF/F specifications) was placed before the trapping zone. Simulations showed that NO/NO2 reacts with isoprene, initiating chain reactions to produce hydroxyl radical, which abstracts hydrogen from acetaldehyde to generate acetyl radical. These mechanisms can account for the full amount of acetyl radical detected experimentally from cigarette smoke. Similar mechanisms may generate radicals in second hand smoke.

  3. Reduction of Smoke-Generation Ability of Construction Timber

    Directory of Open Access Journals (Sweden)

    Pokrovskaya Elena

    2016-01-01

    Full Text Available The problem of reduction of smoke-generation ability for construction timber is of high importance as the smokes and toxic combustion products generating in the course of these materials burning are one of the most dangerous fire factors which threaten life and health of people. According to data presented by Ministry of Emergency Situations of the Russian Federation, rate of mortality due to smoke and toxic combustion gases is more than 70% of total number of people deaths in fires. In this paper, influence of phosphorus-containing modifiers to smoke-generation ability of timber, and also dependence of smoke-generation ability on chemical reactivity of the modifier in interaction with timber has been studied. The problem on fumigation at construction timber burning can be solved by development of chemical compositions efficiently reacting with the surface layer of the timber so that diffusion of solid carbonaceous particles from the timber surface into atmosphere decreases.

  4. Neutrophil superoxide-anion generating capacity in chronic smoking ...

    Indian Academy of Sciences (India)

    We investigated whether long-term -tocopherol therapy in chronic smoking affects superoxide generating capacity of neutrophils ex vivo. To this purpose, we randomly assigned 128 male chronic smokers (37 ± 21 pack years of smoking) to treatment with placebo ( = 64) or -tocopherol (400 IU dL--tocopherol daily, ...

  5. Gender differences in adolescent smoking: mediator and moderator effects of self-generated expected smoking outcomes.

    Science.gov (United States)

    Vidrine, Jennifer Irvin; Anderson, Cheryl B; Pollak, Kathryn I; Wetter, David W

    2006-01-01

    To examine relations among gender, self-generated smoking-outcome expectancies, and smoking in adolescents. Students from one all-girls' (n=350; 53%) and one all-boys' (n=315; 47%) Catholic high school participated. Analyses included binary and ordinal logistic regression. For boys, smoking behavior was associated with buzz (odds radio [OR] = 1.92, 95% confidence interval [CI]: 1.31-2.83, p exercise/sport impairment (OR = 2.84, 95% CI: 1.68-4.81, p gender-smoking relationship. Moderators included negative social (beta = -0.45, p = .021) and enhance self-esteem (beta = -1.07, p = .024). Interventions might benefit from tailoring on gender differences in smoking-outcome expectancies.

  6. Reduction in oxidatively generated DNA damage following smoking cessation

    Directory of Open Access Journals (Sweden)

    Freund Harold G

    2011-05-01

    Full Text Available Abstract Background Cigarette smoking is a known cause of cancer, and cancer may be in part due to effects of oxidative stress. However, whether smoking cessation reverses oxidatively induced DNA damage unclear. The current study sought to examine the extent to which three DNA lesions showed significant reductions after participants quit smoking. Methods Participants (n = 19 in this study were recruited from an ongoing 16-week smoking cessation clinical trial and provided blood samples from which leukocyte DNA was extracted and assessed for 3 DNA lesions (thymine glycol modification [d(TgpA]; formamide breakdown of pyrimidine bases [d(TgpA]; 8-oxo-7,8-dihydroguanine [d(Gh] via liquid chromatography tandem mass spectrometry (LC-MS/MS. Change in lesions over time was assessed using generalized estimating equations, controlling for gender, age, and treatment condition. Results Overall time effects for the d(TgpA (χ2(3 = 8.068, p fpA (χ2(3 = 8.477, p h (χ2(3 = 37.599, p gpA and d(PfpA lesions show relatively greater rebound at Week 16 compared to the d(Gh lesion (88% of baseline for d(TgpA, 64% of baseline for d(PfpA, vs 46% of baseline for d(Gh. Conclusions Overall, results from this analysis suggest that cigarette smoking contributes to oxidatively induced DNA damage, and that smoking cessation appears to reduce levels of specific damage markers between 30-50 percent in the short term. Future research may shed light on the broader array of oxidative damage influenced by smoking and over longer durations of abstinence, to provide further insights into mechanisms underlying carcinogenesis.

  7. Particle size-dependent radical generation from wildland fire smoke

    International Nuclear Information System (INIS)

    Leonard, Stephen S.; Castranova, Vince; Chen, Bean T.; Schwegler-Berry, Diane; Hoover, Mark; Piacitelli, Chris; Gaughan, Denise M.

    2007-01-01

    Firefighting, along with construction, mining and agriculture, ranks among the most dangerous occupations. In addition, the work environment of firefighters is unlike that of any other occupation, not only because of the obvious physical hazards but also due to the respiratory and systemic health hazards of smoke inhalation resulting from combustion. A significant amount of research has been devoted to studying municipal firefighters; however, these studies may not be useful in wildland firefighter exposures, because the two work environments are so different. Not only are wildland firefighters exposed to different combustion products, but their exposure profiles are different. The combustion products wildland firefighters are exposed to can vary greatly in characteristics due to the type and amount of material being burned, soil conditions, temperature and exposure time. Smoke inhalation is one of the greatest concerns for firefighter health and it has been shown that the smoke consists of a large number of particles. These smoke particles contain intermediates of hydrogen, carbon and oxygen free radicals, which may pose a potential health risk. Our investigation looked into the involvement of free radicals in smoke toxicity and the relationship between particle size and radical generation. Samples were collected in discrete aerodynamic particle sizes from a wildfire in Alaska, preserved and then shipped to our laboratory for analysis. Electron spin resonance was used to measure carbon-centered as well as hydroxyl radicals produced by a Fenton-like reaction with wildfire smoke. Further study of reactive oxygen species was conducted using analysis of cellular H 2 O 2 generation, lipid peroxidation of cellular membranes and DNA damage. Results demonstrate that coarse size-range particles contained more carbon radicals per unit mass than the ultrafine particles; however, the ultrafine particles generated more ·OH radicals in the acellular Fenton-like reaction. The

  8. Particle Morphology and Elemental Composition of Smoke Generated by Overheating Common Spacecraft Materials

    Science.gov (United States)

    Meyer, Marit E.

    2015-01-01

    Fire safety in the indoor spacecraft environment is concerned with a unique set of fuels which are designed to not combust. Unlike terrestrial flaming fires, which often can consume an abundance of wood, paper and cloth, spacecraft fires are expected to be generated from overheating electronics consisting of flame resistant materials. Therefore, NASA prioritizes fire characterization research for these fuels undergoing oxidative pyrolysis in order to improve spacecraft fire detector design. A thermal precipitator designed and built for spacecraft fire safety test campaigns at the NASA White Sands Test Facility (WSTF) successfully collected an abundance of smoke particles from oxidative pyrolysis. A thorough microscopic characterization has been performed for ten types of smoke from common spacecraft materials or mixed materials heated at multiple temperatures using the following techniques: SEM, TEM, high resolution TEM, high resolution STEM and EDS. Resulting smoke particle morphologies and elemental compositions have been observed which are consistent with known thermal decomposition mechanisms in the literature and chemical make-up of the spacecraft fuels. Some conclusions about particle formation mechanisms are explored based on images of the microstructure of Teflon smoke particles and tar ball-like particles from Nomex fabric smoke.

  9. Transmission of Smoking across Three Generations in Finland

    Science.gov (United States)

    El-Amin, Salma E. T.; Kinnunen, Jaana M.; Ollila, Hanna; Helminen, Mika; Alves, Joana; Lindfors, Pirjo; Rimpelä, Arja H.

    2015-01-01

    The influence of parents’ smoking on children’s smoking is well known, but few studies have examined the association between grandparents’ and grandchildren’s smoking. We studied the association between paternal and maternal grandparents’ smoking and their grandchildren’s tobacco use and assessed whether parents’ smoking is a mediator in this process. Data were obtained from a national survey of 12–18-year-old Finns in 2013 (N = 3535, response rate 38%). Logistic regression and mediation analyses were used. Both boys and girls had higher odds for smoking experimentation, daily smoking and other tobacco or tobacco-like product use if their mother, father or any of the four grandparents were current or former smokers. When parents’ and grandparents’ smoking status were included in the same model, grandparents’ smoking generally lost statistical significance. In the mediation analysis, 73% of the total effect of grandparents’ smoking on grandchildren’s daily smoking was mediated through parents’ smoking, 64% on smoking experimentation and 63% on other tobacco or tobacco-like product use. The indirect effect of a mother’s smoking was higher than that of a father’s. To conclude, paternal and maternal grandparents’ smoking increases grandchildren’s tobacco use. The influence is mainly, but not completely, mediated through parents’ smoking. PMID:26712771

  10. Propagation of Fire Generated Smoke in Shipboard Spaces with Geometric Interferences

    National Research Council Canada - National Science Library

    Abaya, Amado

    2000-01-01

    The propagation of fire generated smoke into a shipboard space with a geometric interference has been modeled using commercial software from the Computational Fluid Dynamics Research Corporation (CFDRC...

  11. The Intergenerational Transmission of Smoking Across Three Cohabitant Generations: A Count Data Approach.

    Science.gov (United States)

    Escario, José-Julián; Wilkinson, Anna V

    2015-10-01

    This paper examines the extent to which parent and grandparent smoking influences adolescent smoking and its quantitative implications for tobacco control. It extends similar prior studies by investigating the effects on the probability of becoming a smoker and on the number of cigarettes smoked. Count regressions were used to assess the intergenerational transmission of smoking across three cohabitant generations, simultaneously, using data from the 2010 survey "Encuesta Estatal Sobre Uso De Drogas en Estudiantes de Enseñanzas Secundarias". This survey, of 32,234 students, constitutes a representative sample of Spanish students between 14 and 18 years of age. Living with a mother who smokes, a father who smokes, or a grandparent who smokes reduces the odds of being a non-smoker by 36.1% (OR 0.639), 26.1% (OR 0.739) and 20.3% (OR 0.797), respectively. Parental smoking increases cigarette consumption levels among adolescents. Having a cohabitant mother who smokes increases the number of cigarettes smoked by children by around 18.7% (IRR 1.187), while having a cohabitant father who smokes increases the number by around 12.1% (IRR 1.121). Estimates support the hypothesis that visibility of smoking among parents and grandparents is a strong predictor of smoking among adolescents. Accordingly, quitting smoking by parents and grandparents before children become adolescents appears to be a powerful means to both reduce smoking rates among adolescents and the number of cigarettes smoked by smokers; such decisions appear to exert a stronger influence on the prevalence of smoking and consumption levels than exposure to smoking prevention campaigns at school.

  12. Smoking and increased Alzheimer’s disease risk: A review of potential mechanisms

    Science.gov (United States)

    Durazzo, Timothy C.; Mattsson, Niklas; Weiner, Michael W.

    2014-01-01

    Background Cigarette smoking has been linked with both increased and decreased risk for Alzheimer’s disease (AD). This is relevant for the US military because the prevalence of smoking in the military is approximately 11% higher than in civilians. Methods Systematic review of published studies on the association between smoking and increased risk for AD, and preclinical and human literature on the relationships between smoking, nicotine exposure and AD-related neuropathology. Original data from comparisons of smoking and never-smoking cognitively normal elders on in vivo amyloid imaging are also presented. Results Overall, the literature indicates that former/active smoking is related to a significantly increased risk for AD. Cigarette smoke/smoking is associated with AD neuropathology in preclinical models and humans. Smoking-related cerebral oxidative stress is a potential mechanism promoting AD pathophysiology and increased risk for AD. Conclusions A reduction in the incidence of smoking will likely reduce the future prevalence of AD. PMID:24924665

  13. Propagation of Fire Generated Smoke and Heat Transfer in Shipboard Spaces with a Heat Source

    National Research Council Canada - National Science Library

    Vegara, Billy

    2000-01-01

    The propagation of fire generated smoke and heat transfer into a shipboard space has been computationally modeled using a commercial code generated by Computational Fluid Dynamics Research Corporation (CFDRC...

  14. Apparatus and method for generating mechanical waves

    Science.gov (United States)

    Allensworth, D.L.; Chen, P.J.

    1982-10-25

    Mechanical waves are generated in a medium by subjecting an electromechanical element to an alternating electric field having a frequency which induces mechanical resonance therein and is below any electrical resonance frequency thereof.

  15. Mechanisms of adolescent smoking cessation: roles of readiness to quit, nicotine dependence, and smoking of parents and peers

    NARCIS (Netherlands)

    Kleinjan, M.; Engels, R.C.M.E.; Leeuwe, van J.; Brug, J.; Zundert, van R.M.P.; Eijn, van den R.J.J.M.

    2009-01-01

    Multiple levels of influence should be considered in interventions aimed at the adolescent smoker, including psychological, addiction, peer and parental influences. However, the mechanism by which these variables influence the process of smoking cessation in adolescents is not well elucidated.

  16. Teaching Practice generated stressors and coping mechanisms ...

    African Journals Online (AJOL)

    Teaching Practice generated stressors and coping mechanisms among student teachers in Zimbabwe. ... South African Journal of Education ... We sought to establish stressors and coping mechanisms for student teachers on Teaching Practice from a Christian-related university and a government-owned teachers' college ...

  17. Gaseous products and smoke generation on combustion of the insulation materials of nuclear cables

    International Nuclear Information System (INIS)

    Noguchi, Isamu; Takami, Hiroshi; Ueyama, Michio; Fujimura, Shun-ichi.

    1976-01-01

    Serious requirements have been introduced to the cables used for nuclear power plants on their flame retardation in the IEEE Standard 383-1974. The movements that the users prescribe the quantity of corrosive gas generated from cables are also observed. This report describes on the measured results of the gaseous products generated by burning polyethylene, polyvinyl-chloride (PVC) and their flame-resistant products, and a part of the covering materials of the cables for nuclear power plants (flame-resistant, crosslinking polyethylene, flame-resistant, low hydrochloric acid PVC, flame-resistant jute) in the infra-red rapid heating combustion test facility designed by the Furukawa Electric Co. Ltd. In addition, the report introduces the test method for the smoke generation evaluation of polymers and a part of the measured results. The gaseous products of combustion were collected and determined quantitatively by gas chromatographic method. Since smoke generation is affected greatly by the kinds, shape, atmosphere, temperature, ignition procedure and others of burnt matters, the establishment of the evaluation test method is difficult, and a number of methods have been proposed. As the measured results showed, it is clear that smoke generation increases with the increase of flame resistant reagent addition. The smoke generation of PVC was of course great in quantity because it contains considerable amount of chlorine for its molecular structure. Flame-resistant polyethylene generates smoke much more than polyethylene without flame-resisting treatment because of its flame resistivity, but less than that of PVC. (Wakatsuki, Y.)

  18. The Generative Mechanisms of Open Government Data

    DEFF Research Database (Denmark)

    Jetzek, Thorhildur; Avital, Michel; Bjørn-Andersen, Niels

    2013-01-01

    archetypical generative mechanisms. The framework outlines the different pathways to value generation an d highlights the current tension between the private/public and economic/social domains. Second, we offer a conceptual model that provides a systematic way of articulating and examining further...... their data for access and re-use by public and private agents alike. The recent phenomenon of Open Government Data (OGD) has spread around the world, driven by the proposition that opening government data has the ability to generate both economic and social value. However, a review of the academic research...... and the popular press reveals only sporadic attention given to various aspects with no overarching framework that explains how OGD generates value. We apply a critical realist approach to uncover the generative mechanisms that serve to explain this relationship. First, we present a strategic framework with four...

  19. Analysis of electrocautery generated smoke by chromatographic-mass spectrometry.

    Science.gov (United States)

    Kalil, Jefferson; Pessine, Francisco B T; Fidelis, Carlos H V; Menezes, Fabio H; Palma, Paulo Cesar Rodrigues

    2016-01-01

    to analyze the chemical components of the smoke from electrocautery from coagulating muscle and liver tissues of pigs. we collected smoke produced by electrocautery applied to porcine tissue in previously evacuated bottles, with qualitative and quantitative analysis of the compounds present through the hyphenated technique gas chromatography / mass spectrometry. there was a majority of decanal aldehyde in the fumes from the subcutaneous, muscle and liver tissues. Fumes of subcutaneous and muscular tissues also showed the presence of hexanal and phenol. In the fumes of subcutaneous and liver tissues we also found toluene and limonene and, finally, nonanal smoke was present in the muscle and liver tissues. there is increasing evidence showing that smoke from electrocautery used in subcutaneous, muscle and liver tissue is harmful to human health. Thus, there is need to reduce exposure to it or wear masks with filters capable of retaining these particles. analisar quimicamente os componentes da fumaça do eletrocautério, provenientes da coagulação de tecidos, muscular e hepático de suino. coleta de fumaça produzida por eletrocauterização de tecido porcino em frascos previamente evacuados com análise qualitativa e quantitativa dos compostos presentes, através de técnica hifenada, cromatografia a gás/espectrometria de massas. houve presença majoritária do aldeído decanal nas fumaças provenientes dos tecidos subcutâneo, muscular e hepático. Fumaças dos tecidos subcutâneo e muscular mostraram também a presença de hexanal e fenol. Nas fumaças dos tecidos subcutâneo e hepático foram encontrados ainda tolueno e limoneno e, por fim, nonanal estava presente nas fumaças dos tecidos muscular e hepático. há número crescente de evidências mostrando que fumaça proveniente de eletrocauterização de tecidos subcutâneo, muscular e hepático é nociva à saúde de seres humanos. Portanto, há necessidade de reduzir a exposição a ela ou usar máscara com

  20. Smoking-induced Skeletal Muscle Dysfunction. From Evidence to Mechanisms

    NARCIS (Netherlands)

    Degens, H.; Gayan-Ramirez, G.; Hees, H.W.H. van

    2015-01-01

    Smoking is the most important risk factor for the development of chronic obstructive pulmonary disease (COPD). Patients with COPD commonly suffer from skeletal muscle dysfunction, and it has been suggested that cigarette smoke exposure contributes to the development of skeletal muscle dysfunction

  1. Second Generation Electronic Nicotine Delivery System Vape Pen Exposure Generalizes as a Smoking Cue.

    Science.gov (United States)

    King, Andrea C; Smith, Lia J; McNamara, Patrick J; Cao, Dingcai

    2018-01-05

    Second generation electronic nicotine delivery systems (ENDS; also known as e-cigarettes, vaporizers or vape pens) are designed for a customized nicotine delivery experience and have less resemblance to regular cigarettes than first generation "cigalikes." The present study examined whether they generalize as a conditioned cue and evoke smoking urges or behavior in persons exposed to their use. Data were analyzed in N = 108 young adult smokers (≥5 cigarettes per week) randomized to either a traditional combustible cigarette smoking cue or a second generation ENDS vaping cue in a controlled laboratory setting. Cigarette and e-cigarette urge and desire were assessed pre- and post-cue exposure. Smoking behavior was also explored in a subsample undergoing a smoking latency phase after cue exposure (N = 26). The ENDS vape pen cue evoked both urge and desire for a regular cigarette to a similar extent as that produced by the combustible cigarette cue. Both cues produced similar time to initiate smoking during the smoking latency phase. The ENDS vape pen cue elicited smoking urge and desire regardless of ENDS use history, that is, across ENDS naїve, lifetime or current users. Inclusion of past ENDS or cigarette use as covariates did not significantly alter the results. These findings demonstrate that observation of vape pen ENDS use generalizes as a conditioned cue to produce smoking urge, desire, and behavior in young adult smokers. As the popularity of these devices may eventually overtake those of first generation ENDS cigalikes, exposure effects will be of increasing importance. This study shows that passive exposure to a second generation ENDS vape pen cue evoked smoking urge, desire, and behavior across a range of daily and non-daily young adult smokers. Smoking urge and desire increases after vape pen exposure were similar to those produced by exposure to a first generation ENDS cigalike and a combustible cigarette, a known potent cue. Given the increasing

  2. Neutrophil superoxide-anion generating capacity in chronic smoking ...

    Indian Academy of Sciences (India)

    reflected by lag time of conjugated diene formation) was higher in the supplemented group than in the placebo group (+ 22%, < 0.0001). Superoxide generating capacity of neutrophils and superoxide production in diluted whole blood did not differ ...

  3. [Effects of smoking on the cellular mechanisms in the respiratory system].

    Science.gov (United States)

    Chorostowska-Wynimko, Joanna

    2008-01-01

    Devastating effects of smoking on the respiratory system are commonly acknowledged. However, detailed knowledge of the responsible mechanisms is insufficient to allow early diagnosis and effective treatment of the smoking-related pathologies. This paper presents a review of key processes occuring in the smokers' lungs, particularly these responsible for the persistent inflammatory response and neoplastic transformation.

  4. Smoking Cessation Intervention on Facebook: Which Content Generates the Best Engagement?

    Science.gov (United States)

    Thrul, Johannes; Klein, Alexandra B; Ramo, Danielle E

    2015-11-11

    Social media offer a great opportunity to deliver smoking cessation treatment to young adults, but previous online and social media interventions targeting health behavior change have struggled with low participant engagement. We examined engagement generated by content based on the Transtheoretical Model of Behavior Change (TTM) in a motivationally tailored smoking cessation intervention on Facebook. This study aimed to identify which intervention content based on the TTM (Decisional Balance and 10 processes of change) generated the highest engagement among participants in pre-action stages of change (Precontemplation, Contemplation, and Preparation). Participants (N=79, 20% female, mean age 20.8) were assessed for readiness to quit smoking and assigned to one of 7 secret Facebook groups tailored to their stage of change. Daily postings to the groups based on TTM Decisional Balance and the 10 processes of change were made by research staff over 3 months. Engagement was operationalized as the number of participant comments to each post. TTM content-based predictors of number of comments were analyzed and stratified by baseline stage of change, using negative binomial regression analyses with and without zero inflation. A total of 512 TTM-based posts generated 630 individual comments. In Precontemplation and Contemplation groups, Decisional Balance posts generated above average engagement (P=.01 and Ppros and cons of behavior change, while those in the Preparation stage engaged most when posts increased awareness about smoking and smoking cessation. Findings support tailoring intervention content to readiness to quit and suggest intervention components that may be most effective in generating high participant engagement on social media.

  5. In-vitro investigations on laser-induced smoke generation mimicking the laparoscopic laser surgery purposes.

    Science.gov (United States)

    Khoder, Wael Y; Stief, Christian G; Fiedler, Sebastian; Pongratz, Thomas; Beyer, Wolfgang; Hennig, Georg; Rühm, Adrian; Sroka, Ronald

    2015-09-01

    Intraoperative smoke-generation limits the quality of vision during laparoscopic/endoscopic laser-assisted surgeries. The current study aimed at the evaluation of factors affecting this phenomenon. As a first step, a suitable experimental setup and a test tissue model were established for this investigation. The experimental setup is composed of a specific sample container, a laser therapy component suitable for the ablation of model tissue at different treatment wavelengths (λ = 980 nm, 1350 nm, 1470 nm), a suction unit providing continuous smoke extraction, and a detection unit for smoke quantification via detection of light (λ = 633 nm) scattered from smoke particles. The ablation rate (AR) was calculated by dividing the ablated volume by the ablation time (60 sec). The laser-induced scattering signal intensity of the smoke (SI) was determined from time-charts of the signal intensity as a measure for vision, in addition a delay-time tdelay could be derived defining the onset of SI after the laser was switched on. The ratio SI/AR is used as a measure for smoke generation in relation to the ablation rate. Additionally the light transmission of the tissue samples was used to estimate their optical properties. In this set-up, smoke generation using λ = 980 nm as ablation laser wavelength was detected after a delay-time tdelay = (121.6 ± 24.8) sec which is significantly longer compared to the wavelengths λ = 1350 nm with tdelay = (89.8 ± 19.3) sec and λ = 1470 nm with tdelay = (24.7 ± 5.4) sec. Thus, the delay Experimental set-up consisting of sample container, laser therapy component, suction unit and scattered-light detection compartment. time is wavelength-dependent. The SI/AR ratio was significantly different (p < 0.001) for 1470 nm irradiation compared to 980 nm irradiation [SI/AR(1470) = (11.8 ± 2.6) · 10(3) vs. SI/AR(980) = (8.6 ± 2.0) · 10(3) ]. The ablation crater for 980 nm irradiation was comparable with 1470 nm irradiation, but the

  6. Prenatal parental tobacco smoking, gene specific DNA methylation, and newborns size: the Generation R study

    NARCIS (Netherlands)

    M.I. Both (Marieke); N.H. van Mil (Nina); C.P. Tolhoek (Catharina P.); L. Stolk (Lisette); P.H.C. Eilers (Paul); M.M.P.J. Verbiest (Michael); B.T. Heijman (Bastiaan); A.G. Uitterlinden (André); A. Hofman (Albert); M.H. van IJzendoorn (Rien); L. Duijts (Liesbeth); J.C. de Jongste (Johan); H.W. Tiemeier (Henning); E.A.P. Steegers (Eric); V.W.V. Jaddoe (Vincent); R.P.M. Steegers-Theunissen (Régine)

    2015-01-01

    textabstractBackground: Deleterious effects of prenatal tobacco smoking on fetal growth and newborn weight are well-established. One of the proposed mechanisms underlying this relationship is alterations in epigenetic programming. We selected 506 newborns from a population-based prospective birth

  7. Power Generation Using Mechanical Wave Energy Converter

    Directory of Open Access Journals (Sweden)

    Srinivasan Chandrasekaran

    2012-03-01

    Full Text Available Ocean wave energy plays a significant role in meeting the growing demand of electric power. Economic, environmental, and technical advantages of wave energy set it apart from other renewable energy resources. Present study describes a newly proposed Mechanical Wave Energy Converter (MEWC that is employed to harness heave motion of floating buoy to generate power. Focus is on the conceptual development of the device, illustrating details of component level analysis. Employed methodology has many advantages such as i simple and easy fabrication; ii easy to control the operations during rough weather; and iii low failure rate during normal sea conditions. Experimental investigations carried out on the scaled model of MWEC show better performance and its capability to generate power at higher efficiency in regular wave fields. Design Failure Mode and Effect Analysis (FMEA shows rare failure rates for all components except the floating buoy.

  8. Reaction Mechanism Generator: Automatic construction of chemical kinetic mechanisms

    Science.gov (United States)

    Gao, Connie W.; Allen, Joshua W.; Green, William H.; West, Richard H.

    2016-06-01

    Reaction Mechanism Generator (RMG) constructs kinetic models composed of elementary chemical reaction steps using a general understanding of how molecules react. Species thermochemistry is estimated through Benson group additivity and reaction rate coefficients are estimated using a database of known rate rules and reaction templates. At its core, RMG relies on two fundamental data structures: graphs and trees. Graphs are used to represent chemical structures, and trees are used to represent thermodynamic and kinetic data. Models are generated using a rate-based algorithm which excludes species from the model based on reaction fluxes. RMG can generate reaction mechanisms for species involving carbon, hydrogen, oxygen, sulfur, and nitrogen. It also has capabilities for estimating transport and solvation properties, and it automatically computes pressure-dependent rate coefficients and identifies chemically-activated reaction paths. RMG is an object-oriented program written in Python, which provides a stable, robust programming architecture for developing an extensible and modular code base with a large suite of unit tests. Computationally intensive functions are cythonized for speed improvements.

  9. Pathogenic mechanisms in chronic obstructive pulmonary disease due to biomass smoke exposure.

    Science.gov (United States)

    Silva, Rafael; Oyarzún, Manuel; Olloquequi, Jordi

    2015-06-01

    Chronic obstructive pulmonary disease (COPD) mortality and morbidity have increased significantly worldwide in recent decades. Although cigarette smoke is still considered the main risk factor for the development of the disease, estimates suggest that between 25% and 33% of COPD patients are non-smokers. Among the factors that may increase the risk of developing COPD, biomass smoke has been proposed as one of the most important, affecting especially women and children in developing countries. Despite the epidemiological evidence linking exposure to biomass smoke with adverse health effects, the specific cellular and molecular mechanisms by which this pollutant can be harmful for the respiratory and cardiovascular systems remain unclear. In this article we review the main pathogenic mechanisms proposed to date that make biomass smoke one of the major risk factors for COPD. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

  10. Neural mechanisms of sequence generation in songbirds

    Science.gov (United States)

    Langford, Bruce

    Animal models in research are useful for studying more complex behavior. For example, motor sequence generation of actions requiring good muscle coordination such as writing with a pen, playing an instrument, or speaking, may involve the interaction of many areas in the brain, each a complex system in itself; thus it can be difficult to determine causal relationships between neural behavior and the behavior being studied. Birdsong, however, provides an excellent model behavior for motor sequence learning, memory, and generation. The song consists of learned sequences of notes that are spectrographically stereotyped over multiple renditions of the song, similar to syllables in human speech. The main areas of the songbird brain involve in singing are known, however, the mechanisms by which these systems store and produce song are not well understood. We used a custom built, head-mounted, miniature motorized microdrive to chronically record the neural firing patterns of identified neurons in HVC, a pre-motor cortical nucleus which has been shown to be important in song timing. These were done in Bengalese finch which generate a song made up of stereotyped notes but variable note sequences. We observed song related bursting in neurons projecting to Area X, a homologue to basal ganglia, and tonic firing in HVC interneurons. Interneuron had firing rate patterns that were consistent over multiple renditions of the same note sequence. We also designed and built a light-weight, low-powered wireless programmable neural stimulator using Bluetooth Low Energy Protocol. It was able to generate perturbations in the song when current pulses were administered to RA, which projects to the brainstem nucleus responsible for syringeal muscle control.

  11. Simulation analysis on the influence of smoke flow in special section tunnel under mechanical ventilation

    Science.gov (United States)

    Li, Weicong; Wei, Gewei; Xiao, Jianqing; Zhong, Shengyuan; Liu, Wanfu

    2017-09-01

    In this study, a special section tunnel model was established by using FDS (Fire Dynamics Simulator). In the condition of mechanical ventilation, studied the effect of the model for exhaust velocity interval and curvature, slope on the smoke flow. Finally, the longitudinal wind speed of 3m/s is determined, and the results show that the curvature and slope of the tunnel have no effect on the smoke flow.

  12. Modeling and Generating Strategy Games Mechanics

    DEFF Research Database (Denmark)

    Mahlmann, Tobias

    Strategy games are a popular genre of games with a long history, originating from games like Chess or Go. The first strategy games were published as “Kriegspiele” (engl. wargames) in the late 18th century, intended for the education of young cadets. Since then strategy games were refined...... and transformed over two centuries into a medium of entertainment. Today’s computer strategy games have their roots in the board- and roleplaying games of the 20th century and enjoy great popularity. We use strategy games as an application for the procedural generation of game content. Procedural game content...... of the game is, how players may manipulate the game world, etc. We present the Strategy Games Description Language (SGDL), a tree-based approach to model the game mechanics of strategy games. SGDL allows game designers to rapid prototype their game ideas with the help of our customisable game engine. We...

  13. Neutrophil superoxide-anion generating capacity in chronic smoking: effect of long-term alpha-tocopherol therapy

    NARCIS (Netherlands)

    Tits, van L.; Waart, de F.; Hak-Lemmers, H.L.M.; Graaf, de J.; Demacker, P.N.; Stalenhoef, A.F.

    2003-01-01

    We investigated whether long-term alpha-tocopherol therapy in chronic smoking affects superoxide generating capacity of neutrophils ex vivo. To this purpose, we randomly assigned 128 male chronic smokers (37 21 pack years of smoking) to treatment with placebo (n = 64) or alpha-tocopherol (400 IU

  14. PREVALENCE OF TOBACCO USE AMONG CHILDREN AND ADOLESCENTS WITH AN ANALYSIS INFLUENCE OF SMOKING ON HEALTH STATUS YOUNGER GENERATION

    Directory of Open Access Journals (Sweden)

    N.A. Il'enkova

    2011-01-01

    Full Text Available Review is devoted to the prevalence of smoking among children and adolescents, given the steady increase in illness, a risk factor which is smoking. Detection disease at a stage before the disease, clinical manifestations, requires the implementation of demonstration and preferably noninvasive studies of children. Shown that early intervention in the prevalence of tobacco use would decrease the disease from respiratory and cardiovascular systems, and hence improve the quality of life of future generations. Key words: smoking, passive smoking, research methods smokers, teenagers. (Voprosy sovremennoi pediatrii — Current Pediatrics. — 2011; 10 (5: 5–9.

  15. Inferring Smoking Status from User Generated Content in an Online Cessation Community.

    Science.gov (United States)

    Amato, Michael S; Papandonatos, George D; Cha, Sarah; Wang, Xi; Zhao, Kang; Cohn, Amy M; Pearson, Jennifer L; Graham, Amanda L

    2018-01-22

    User generated content (UGC) is a valuable but underutilized source of information about individuals who participate in online cessation interventions. This study represents a first effort to passively detect smoking status among members of an online cessation program using UGC. Secondary data analysis was performed on data from 826 participants in a web-based smoking cessation randomized trial that included an online community. Domain experts from the online community reviewed each post and comment written by participants and attempted to infer the author's smoking status at the time it was written. Inferences from UGC were validated by comparison with self-reported 30-day point prevalence abstinence (PPA). Following validation, the impact of this method was evaluated across all individuals and timepoints in the study period. Of the 826 participants in the analytic sample, 719 had written at least one post from which content inference was possible. Among participants for whom unambiguous smoking status was inferred during the 30 days preceding their 3-month follow-up survey, concordance with self-report was almost perfect (kappa = 0.94). Posts indicating abstinence tended to be written shortly after enrollment (median = 14 days). Passive inference of smoking status from UGC in online cessation communities is possible and highly reliable for smokers who actively produce content. These results lay the groundwork for further development of observational research tools and intervention innovations. © The Author(s) 2018. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Mechanisms linking socioeconomic status to smoking cessation: a structural equation modeling approach.

    Science.gov (United States)

    Businelle, Michael S; Kendzor, Darla E; Reitzel, Lorraine R; Costello, Tracy J; Cofta-Woerpel, Ludmila; Li, Yisheng; Mazas, Carlos A; Vidrine, Jennifer Irvin; Cinciripini, Paul M; Greisinger, Anthony J; Wetter, David W

    2010-05-01

    Although there has been a socioeconomic gradient in smoking prevalence, cessation, and disease burden for decades, these disparities have become even more pronounced over time. The aim of the current study was to develop and test a conceptual model of the mechanisms linking socioeconomic status (SES) to smoking cessation. The conceptual model was evaluated using a latent variable modeling approach in a sample of 424 smokers seeking treatment (34% African American; 33% Latino; 33% White). Hypothesized mechanisms included social support, neighborhood disadvantage, negative affect/stress, agency, and craving. The primary outcome was Week 4 smoking status. As was hypothesized, SES had significant direct and indirect effects on cessation. Specifically, neighborhood disadvantage, social support, negative affect/stress, and agency mediated the relation between SES and smoking cessation. A multiple group analysis indicated that the model was a good fit across racial/ethnic groups. The present study yielded one of the more comprehensive models illuminating the specific mechanisms that link SES and smoking cessation. Policy, community, and individual-level interventions that target low SES smokers and address the specific pathways identified in the current model could potentially attenuate the impact of SES on cessation. (c) 2010 APA, all rights reserved.

  17. Interlinked bistable mechanisms generate robust mitotic transitions.

    Science.gov (United States)

    Hutter, Lukas H; Rata, Scott; Hochegger, Helfrid; Novák, Béla

    2017-10-18

    The transitions between phases of the cell cycle have evolved to be robust and switch-like, which ensures temporal separation of DNA replication, sister chromatid separation, and cell division. Mathematical models describing the biochemical interaction networks of cell cycle regulators attribute these properties to underlying bistable switches, which inherently generate robust, switch-like, and irreversible transitions between states. We have recently presented new mathematical models for two control systems that regulate crucial transitions in the cell cycle: mitotic entry and exit, 1 and the mitotic checkpoint. 2 Each of the two control systems is characterized by two interlinked bistable switches. In the case of mitotic checkpoint control, these switches are mutually activating, whereas in the case of the mitotic entry/exit network, the switches are mutually inhibiting. In this Perspective we describe the qualitative features of these regulatory motifs and show that having two interlinked bistable mechanisms further enhances robustness and irreversibility. We speculate that these network motifs also underlie other cell cycle transitions and cellular transitions between distinct biochemical states.

  18. Noise generation mechanisms in claw pole alternators

    Science.gov (United States)

    Eversman, W.; Burns, S.; Pekarek, S.; Bai, Hua; Tichenor, J.

    2005-05-01

    Noise of claw pole alternators, generated electromagnetically and structurally radiated, has been the subject of an extensive research program. The goal has been to identify and reduce noise radiation mechanisms in claw pole (Lundell) alternators used in automotive applications. Two approaches have been followed. In the first, electromagnetic sources of noise have been investigated by lumped parameter and magnetically equivalent circuit modeling and simulation, and by related experimentation. This is the subject of separate papers. The second, concurrent study reported here has investigated machine and mount responses to an electromagnetically generated torque ripple. Modeling and experimentation has led to the conclusion that there exists a high correlation between electromagnetic sources, torque ripple, and radiated noise. Experimentation also has led to the conclusion that noise characteristics of a given machine are substantially altered by modification of the mounting configuration. The work reported here involves modeling, simulation, and experiment to isolate machine dynamic characteristics and mounting geometries which contribute to strong coupling between torque ripple and machine/mount dynamic response. A low-order model of the alternator which includes shaft flexibility, gyroscopic effects, shaft bearing asymmetry, mounting lug geometry, and mounting structure dynamics has been created. The model provides a rapid simulation of dynamic response in the form of a transfer function between torque ripple and mounting forces. Generic studies of a simplified mounting structure coupled to the machine model are presented here. Acoustic testing of several machine configurations on a production mount has been carried out to investigate 36th order noise in three phase machines and 72nd order noise in six-phase machines. Electromagnetic modeling and dynamic response simulations suggest that the six-phase machine is inherently quieter. This is supported by

  19. Why Does ADHD Confer Risk for Cigarette Smoking? A Review of Psychosocial Mechanisms

    Science.gov (United States)

    Glass, Kerrie; Flory, Kate

    2010-01-01

    Research has documented that adolescents and young adults with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for cigarette smoking, but less attention has examined why this risk exists. The current paper reviews the literature on different psychosocial mechanisms [self-medication hypothesis, social factors (social modeling,…

  20. Generation of Articulated Mechanisms by Optimization Techniques

    DEFF Research Database (Denmark)

    Kawamoto, Atsushi

    2004-01-01

    mechanisms. A critical issue for designing articulated mechanisms is geometric non-linearity in the kinematics. This should be considered for the analysis of mechanisms since the displacements of mechanisms are intrinsically large. The consideration of geometric non-linearity, however, causes numerical...... difficulties relating to the non-convexity of the potential energy defining the equilibrium equations. It is thus essential to implement a numerical method that can – in a consistent way – detect a stable equilibrium point; the quality of the equilibrium analysis not only is important for itself but also...... directly affects the result of the associated sensitivity analysis. Another critical issue for mechanism design is the concept of mechanical degrees of freedom and this should be also considered for obtaining a proper articulated mechanism. The thesis treats this inherently discrete criterion in some...

  1. Mechanism of power generation - the MHD way

    International Nuclear Information System (INIS)

    Rangachari, S.; Ramash, V.R.; Subramanian, C.K.

    1975-01-01

    The basic physical principles of magnetohydrodynamics and the application of this principle for power generation (direct energy conversion) are explained. A magnetohydrodynamic generator (MHDG) is described both in the Faraday and Hall modes. The advantages of the Faraday mode and the Hall mode for different geometries of the generator are mentioned. The conductor used is a fluid - an ionised gas (plasma) or a liquid metal at high temperature. The difficulties in maintaining high temperature and high velocity for the gas and very low temperature at the same time side by side for superconducting magnets to produce a strong magnetic field, are pointed out. The most commonly used gas is purified air. The advantages of MHD generators and the present power crisis have compelled further research in this field in spite of the high costs involved. (A.K.)

  2. Payment mechanisms for micro-generation

    Energy Technology Data Exchange (ETDEWEB)

    Choudhury, W.; Andrews, S.

    2002-07-01

    The Department of Trade and Industry commissioned a study into payment options for the increasing number of micro-generators (in domestic dwellings and where the generating capacity is not more than 5kW i.e. essentially micro-CHP and photovoltaics) supplying power for the national distribution network. It is shown that small generators will impact on all aspects of industry and connection will need to be simplified. The network will call for a more actively managed regime. Metering will need to be more sophisticated and agreement reached on how costs should be allocated when demand is low and surplus electricity is exported to the system. Three options were considered to be viable.

  3. ON THE TOPOLOGY OF MECHANISMS DESIGNED FOR CURVES GENERATION

    Directory of Open Access Journals (Sweden)

    MEREUTA Elena

    2008-07-01

    Full Text Available The paper presents some mechanisms used for generating simple or complex curves. The mechanisms are shown in different positions and for some special curves the demonstrations are performed.

  4. High school cigarette smoking and post-secondary education enrollment: Longitudinal findings from the NEXT Generation Health Study.

    Science.gov (United States)

    Sabado, Melanie D; Haynie, Denise; Gilman, Stephen E; Simons-Morton, Bruce; Choi, Kelvin

    2017-12-01

    The inverse association between smoking and educational attainment has been reported in cross-sectional studies. Temporality between smoking and education remains unclear. Our study examines the prospective association between high school cigarette and smoking post-secondary education enrollment. Data were collected from a nationally representative cohort of 10th graders who participated in the Next Generation Health Study (2010-2013). Ethnicity/race, urbanicity, parental education, depression symptoms, and family affluence were assessed at baseline. Self-reported 30-day smoking was assessed annually from 2010 to 2012. Post-secondary education enrollment was measured in 2013 and categorized as either not enrolled or enrolled in technical school, community college, or 4-year college/university. Multinomial logistic regression was used to evaluate the association between cigarette smoking duration and post-secondary education enrollment (N=1681). Participants who smoked 1, 2, or 3years during high school had lower odds of attending a 4-year college (relative to a no enrollment) than non-smokers (adjusted OR: smoking 1year=0.30, 2years=0.28, 3years=0.14). Similarly, participants who smoked for 2 or 3years were less likely than non-smokers to enroll in community college (adjusted OR: 2years=0.31, 3years=0.40). These associations were independent of demographic and socioeconomic factors. There was a prospective association between high school smoking and the unlikelihood of enrollment in post-secondary education. If this represents a causal association, strategies to prevent/delay smoking onset and promote early cessation in adolescents may provide further health benefits by promoting higher educational attainment. Copyright © 2017. Published by Elsevier Inc.

  5. Addressing a Threat to the Healthfulness of Tomorrow's Generation: The Case of Cigarette Smoking in Nigeria

    Science.gov (United States)

    Egbe, Catherine O.; Petersen, Inge; Meyer-Weitz, Anna

    2014-01-01

    Cigarette smoking has widely received the attention of international and local health bodies. Efforts are being made towards curbing smoking prevalence globally with a view to reduce the health, economic and social effects of smoking in the society. While some developed countries are recording success in this effort mainly through stringent…

  6. PLANAR MECHANISMS USED FOR GENERATING CURVE LINE TRANSLATION MOTION

    Directory of Open Access Journals (Sweden)

    Ovidiu ANTONESCU

    2015-05-01

    Full Text Available The curve line translation motion can be generated in the particular form of the circular translation, through mono-mobile mechanisms with articulated links of simple parallelogram type (with a fixed side or through transmission with toothed belt with a fixed wheel. Also, the circular translation can be generated through planar mechanisms with two cylindrical gears with a fixed central wheel. It is mentioned that the two cylindrical gearings of the Fergusson mechanisms are both exterior and interior.

  7. Mechanical cleaning of steam generators in PWR nuclear power plant

    International Nuclear Information System (INIS)

    Ding Xunshen; Li Sujia

    1994-01-01

    The mechanical cleaning of steam generators and its equipment currently employed internationally and in Daya Bay Nuclear Power Plant are described. The site mechanical cleaning practices for nuclear power plant are also introduced. A number of remarks on mechanical cleaning, chemical cleaning, TV inspection of cleanness and withdrawal of foreign materials are given

  8. Experimental and numerical study of smoke propagation through a vent separating two mechanically ventilated rooms

    Energy Technology Data Exchange (ETDEWEB)

    Audouin, Laurent; Pretrel, Hugues; Vaux, Samuel [Institut de Radioprotection et de Surete Nucleaire (IRSN), Saint Paul Lez Durance (France)

    2015-12-15

    The paper presents an experimental and numerical study about smoke propagation through a horizontal opening between two superposed compartments, as can be encountered in nuclear installations, in case of a fire taking place in the lower room. The experimental configuration proposed in this study consists in two rooms mechanically ventilated and connected each other by a horizontal opening. The fire source is simulated by a propane burner located in the lower room. The inlet ventilation duct is located in the lower room and the exhaust ventilation duct is located in the upper room. For such experimental configuration, several flow regimes at the horizontal opening connecting the two rooms can be encountered depending on the fire power, the opening size (diameter, depth) and the ventilation set-up (location of inlet/outlet ducts, flow rate). Indeed, flow at the opening is governed by buoyant forces due to the hot gases produced by the fire, the inertia effect due to the forced ventilation and the momentum effect due to smoke flow nearby the horizontal opening (for instance, ceiling jet or thermal plume from fire). Consequently, such complex mixed (natural/ forced) convective flows are still a challenge for CFD fire codes to make properly calculations of these experimental scenarios. The objective of this paper is to assess the capability of ISIS code (CFD) to simulate the behaviour of smoke propagation inside these two superposed compartments. Results of this study are presented with details (especially, thermal stratification and flow rates through the horizontal vent) and are discussed thoroughly.

  9. New perspectives on mechanisms of sound generation in songbirds

    DEFF Research Database (Denmark)

    Goller, Franz; Larsen, Ole Næsbye

    2002-01-01

    -tone mechanism similar to human phonation with the labia forming a pneumatic valve. The classical avian model proposed that vibrations of the thin medial tympaniform membranes are the primary sound generating mechanism. As a direct test of these two hypotheses we ablated the medial tympaniform membranes in two......The physical mechanisms of sound generation in the vocal organ, the syrinx, of songbirds have been investigated mostly with indirect methods. Recent direct endoscopic observation identified vibrations of the labia as the principal sound source. This model suggests sound generation in a pulse...... atmosphere) as well as direct (labial vibration during tonal sound) measurements of syringeal vibrations support a vibration-based soundgenerating mechanism even for tonal sounds....

  10. Electrical power generation by mechanically modulating electrical double layers.

    Science.gov (United States)

    Moon, Jong Kyun; Jeong, Jaeki; Lee, Dongyun; Pak, Hyuk Kyu

    2013-01-01

    Since Michael Faraday and Joseph Henry made their great discovery of electromagnetic induction, there have been continuous developments in electrical power generation. Most people today get electricity from thermal, hydroelectric, or nuclear power generation systems, which use this electromagnetic induction phenomenon. Here we propose a new method for electrical power generation, without using electromagnetic induction, by mechanically modulating the electrical double layers at the interfacial areas of a water bridge between two conducting plates. We find that when the height of the water bridge is mechanically modulated, the electrical double layer capacitors formed on the two interfacial areas are continuously charged and discharged at different phases from each other, thus generating an AC electric current across the plates. We use a resistor-capacitor circuit model to explain the results of this experiment. This observation could be useful for constructing a micro-fluidic power generation system in the near future.

  11. Mechanisms of lung endothelial barrier disruption induced by cigarette smoke: role of oxidative stress and ceramides.

    Science.gov (United States)

    Schweitzer, Kelly S; Hatoum, Hadi; Brown, Mary Beth; Gupta, Mehak; Justice, Matthew J; Beteck, Besem; Van Demark, Mary; Gu, Yuan; Presson, Robert G; Hubbard, Walter C; Petrache, Irina

    2011-12-01

    The epithelial and endothelial cells lining the alveolus form a barrier essential for the preservation of the lung respiratory function, which is, however, vulnerable to excessive oxidative, inflammatory, and apoptotic insults. Whereas profound breaches in this barrier function cause pulmonary edema, more subtle changes may contribute to inflammation. The mechanisms by which cigarette smoke (CS) exposure induce lung inflammation are not fully understood, but an early alteration in the epithelial barrier function has been documented. We sought to investigate the occurrence and mechanisms by which soluble components of mainstream CS disrupt the lung endothelial cell barrier function. Using cultured primary rat microvascular cell monolayers, we report that CS induces endothelial cell barrier disruption in a dose- and time-dependent manner of similar magnitude to that of the epithelial cell barrier. CS exposure triggered a mechanism of neutral sphingomyelinase-mediated ceramide upregulation and p38 MAPK and JNK activation that were oxidative stress dependent and that, along with Rho kinase activation, mediated the endothelial barrier dysfunction. The morphological changes in endothelial cell monolayers induced by CS included actin cytoskeletal rearrangement, junctional protein zonula occludens-1 loss, and intercellular gap formation, which were abolished by the glutathione modulator N-acetylcysteine and ameliorated by neutral sphingomyelinase inhibition. The direct application of ceramide recapitulated the effects of CS, by disrupting both endothelial and epithelial cells barrier, by a mechanism that was redox and apoptosis independent and required Rho kinase activation. Furthermore, ceramide induced dose-dependent alterations of alveolar microcirculatory barrier in vivo, measured by two-photon excitation microscopy in the intact rat. In conclusion, soluble components of CS have direct endothelial barrier-disruptive effects that could be ameliorated by glutathione

  12. Comparison of airway pressure release ventilation to conventional mechanical ventilation in the early management of smoke inhalation injury in swine.

    Science.gov (United States)

    Batchinsky, Andriy I; Burkett, Samuel E; Zanders, Thomas B; Chung, Kevin K; Regn, Dara D; Jordan, Bryan S; Necsoiu, Corina; Nguyen, Ruth; Hanson, Margaret A; Morris, Michael J; Cancio, Leopoldo C

    2011-10-01

    The role of airway pressure release ventilation in the management of early smoke inhalation injury has not been studied. We compared the effects of airway pressure release ventilation and conventional mechanical ventilation on oxygenation in a porcine model of acute respiratory distress syndrome induced by wood smoke inhalation. Prospective animal study. Government laboratory animal intensive care unit. Thirty-three Yorkshire pigs. Smoke inhalation injury. Anesthetized female Yorkshire pigs (n = 33) inhaled room-temperature pine-bark smoke. Before injury, the pigs were randomized to receive conventional mechanical ventilation (n = 15) or airway pressure release ventilation (n = 12) for 48 hrs after smoke inhalation. As acute respiratory distress syndrome developed (PaO2/Fio2 ratio conventional mechanical ventilation for 48 hrs and served as time controls. Changes in PaO2/Fio2 ratio, tidal volume, respiratory rate, mean airway pressure, plateau pressure, and hemodynamic variables were recorded. Survival was assessed using Kaplan-Meier analysis. PaO2/Fio2 ratio was lower in airway pressure release ventilation vs. conventional mechanical ventilation pigs at 12, 18, and 24 hrs (p conventional mechanical ventilation animals between 30 and 48 hrs post injury (p animals between 6 and 48 hrs (p conventional mechanical ventilation and airway pressure release ventilation pigs. In this model of acute respiratory distress syndrome caused by severe smoke inhalation in swine, airway pressure release ventilation-treated animals developed acute respiratory distress syndrome faster than conventional mechanical ventilation-treated animals, showing a lower PaO2/Fio2 ratio at 12, 18, and 24 hrs after injury. At other time points, PaO2/Fio2 ratio was not different between conventional mechanical ventilation and airway pressure release ventilation.

  13. VOLCANIC TSUNAMI GENERATING SOURCE MECHANISMS IN THE EASTERN CARIBBEAN REGION

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2004-01-01

    Full Text Available Earthquakes, volcanic eruptions, volcanic island flank failures and underwater slides have generated numerous destructive tsunamis in the Caribbean region. Convergent, compressional and collisional tectonic activity caused primarily from the eastward movement of the Caribbean Plate in relation to the North American, Atlantic and South American Plates, is responsible for zones of subduction in the region, the formation of island arcs and the evolution of particular volcanic centers on the overlying plate. The inter-plate tectonic interaction and deformation along these marginal boundaries result in moderate seismic and volcanic events that can generate tsunamis by a number of different mechanisms. The active geo-dynamic processes have created the Lesser Antilles, an arc of small islands with volcanoes characterized by both effusive and explosive activity. Eruption mechanisms of these Caribbean volcanoes are complex and often anomalous. Collapses of lava domes often precede major eruptions, which may vary in intensity from Strombolian to Plinian. Locally catastrophic, short-period tsunami-like waves can be generated directly by lateral, direct or channelized volcanic blast episodes, or in combination with collateral air pressure perturbations, nuéss ardentes, pyroclastic flows, lahars, or cascading debris avalanches. Submarine volcanic caldera collapses can also generate locally destructive tsunami waves. Volcanoes in the Eastern Caribbean Region have unstable flanks. Destructive local tsunamis may be generated from aerial and submarine volcanic edifice mass edifice flank failures, which may be triggered by volcanic episodes, lava dome collapses, or simply by gravitational instabilities. The present report evaluates volcanic mechanisms, resulting flank failure processes and their potential for tsunami generation. More specifically, the report evaluates recent volcanic eruption mechanisms of the Soufriere Hills volcano on Montserrat, of Mt. Pel

  14. Linear modeling of possible mechanisms for parkinson tremor generation

    NARCIS (Netherlands)

    Lohnberg, P.

    1978-01-01

    The power of Parkinson tremor is expressed in terms of possibly changed frequency response functions between relevant variables in the neuromuscular system. The derivation starts out from a linear loopless equivalent model of mechanisms for general tremor generation. Hypothetical changes in this

  15. Effect of mechanical vibration generated in oscillating/vibratory ...

    African Journals Online (AJOL)

    Background: Whole body vibration (WBV) exercise has been used in health sciences. Authors have reported that changes on the concentration of plasma biomarkers could be associated with the WBV effects. The aim of this investigation is to assess the consequences of exposition of 25 Hz mechanical vibration generated ...

  16. Mechanisms of elastic wave generation in solids by ion impact

    International Nuclear Information System (INIS)

    Deemer, B.; Murphy, J.; Claytor, T.

    1990-01-01

    This study is directed at understanding the mechanisms of acoustic signal generation by modulated beams of energetic ions as a function of ion energy. Interaction of ions with solids initiates a range of processes including sputtering, ion implantation, ionization, both internal and external, as well as thermal deposition in the solid. Accumulated internal stress also occurs by generation of dislocations resulting from, inelastic nuclear scattering of the incident ion beam. With respect to elastic wave generation, two potential mechanisms are thermoelastic induced stress and momentum transfer. The latter process includes contributions of momentum transfer from the incident beam and from ions ejected via sputtering. Other aspects of the generation process include the potential for shock wave generation since the mean particle velocity for a wide range of ion energies exceeds the velocity of sound in solids. This study seeks to distinguish the contribution of these mechanisms by studying the signature, angular distribution and energy dependence of the elastic wave response in the time domain and to use this information to understand technologically important processes such as implantation and sputtering

  17. [Non-nascent hydrogen mechanism of plumbane generation].

    Science.gov (United States)

    Zou, Yan; Jin, Fu-xia; Chen, Zhi-jiang; Qiu, De-ren; Yang, Peng-yuan

    2005-10-01

    The mechanism of plumbane generation in dichromate system was studied via investigation of the relationship between the plumbane yield and the molar number of the reactants. A flow injection hydride generator was used in the study. Reactant moler number was calculated by the injected volume and the reactant concentration, and the plumbane yield was measured via an AAS spectrometer equipped with an electrothermal quartz tube atomizer. Experimental results show that the acid was first used for the neutralization of NaOH and successively participated in the redox reaction of borohydride with dichromate with a constant molar ratio of 9.95 +/- 0.42 (expressed in terms of mean +/- standard deviation). At the same time, plumbane generation was displayed as synchronously taking place with the redox reaction, and the yield increased with the increase of acid. The mechanism of plumbane generation was thus deduced as an induced reaction or a catalytic reaction by the redox reaction. Up to this end, the non-nascent hydrogen mechanism of hydride generation has been verified for all the IVA elements.

  18. Generation of spin currents due to mechanical rotation

    Science.gov (United States)

    Matsuo, Mamoru; Ieda, Jun'ichi; Saitoh, Eiji; Maekawa, Sadamichi

    2011-03-01

    In the frontier of spintronics, much attention is paid on the control and generation of spin currents. Due to the exciting progress of nanomechatrononics, the importance of mechanical manipulation of electron spin will increase. We discuss theoretically effects of mechanical rotation on spin currents using generally covariant Dirac equation with gauge fields in the non-relativistic limit. We derive semi-classical equations of motion for a wavepacket of electrons in two dimentional planes subject to the spin-orbit interaction argumented by a mechanical rotation. We show that a circular spin current is created by the mechanical rotation with a magnetic field. The magnitude of the spin current becomes 108A/m2 in Pt with the magnetic field ~ 1 T and the rotational velocity ~ 1 kHz.

  19. Mechanism and Simulation of Generating Pulsed Strong Magnetic Field

    Science.gov (United States)

    Yang, Xian-Jun; Wang, Shuai-Chuang; Deng, Ai-Dong; Gu, Zhuo-Wei; Luo, Hao

    2014-10-01

    A strong magnetic field (over 1000 T) was recently experimentally produced at the Academy of Engineering Physics in China. The theoretical methods, which include a simple model and MHD code, are discussed to investigate the physical mechanism and dynamics of generating the strong magnetic field. The analysis and simulation results show that nonlinear magnetic diffusion contributes less as compared to the linear magnetic diffusion. This indicates that the compressible hydrodynamic effect and solid imploding compression may have a large influence on strong magnetic field generation.

  20. Evaluate and characterize mechanisms controlling transport, fate, and effects of army smokes in the aerosol wind tunnel: Transport, transformations, fate, and terrestrial ecological effects of hexachloroethane obscurant smokes

    Energy Technology Data Exchange (ETDEWEB)

    Cataldo, D.A.; Ligotke, M.W.; Bolton, H. Jr.; Fellows, R.J.; Van Voris, P.; McVeety, B.D.; Li, Shu-mei W.; McFadden, K.M.

    1989-09-01

    The terrestrial transport, chemical fate, and ecological effects of hexachloroethane (HC) smoke were evaluated under controlled wind tunnel conditions. The primary objectives of this research program are to characterize and assess the impacts of smoke and obscurants on: (1) natural vegetation characteristic of US Army training sites in the United States; (2) physical and chemical properties of soils representative of these training sites; and (3) soil microbiological and invertebrate communities. Impacts and dose/responses were evaluated based on exposure scenarios, including exposure duration, exposure rate, and sequential cumulative dosing. Key to understanding the environmental impacts of HC smoke/obscurants is establishing the importance of environmental parameters such as relative humidity and wind speed on airborne aerosol characteristics and deposition to receptor surfaces. Direct and indirect biotic effects were evaluated using five plant species and two soil types. HC aerosols were generated in a controlled atmosphere wind tunnel by combustion of hexachloroethane mixtures prepared to simulate normal pot burn rates and conditions. The aerosol was characterized and used to expose plant, soil, and other test systems. Particle sizes of airborne HC ranged from 1.3 to 2.1 {mu}m mass median aerodynamic diameter (MMAD), and particle size was affected by relative humidity over a range of 20% to 85%. Air concentrations employed ranged from 130 to 680 mg/m{sup 3}, depending on exposure scenario. Chlorocarbon concentrations within smokes, deposition rates for plant and soil surfaces, and persistence were determined. The fate of principal inorganic species (Zn, Al, and Cl) in a range of soils was assessed.

  1. Molecular and cellular mechanisms of cigarette smoke-induced myocardial injury: prevention by vitamin C.

    Directory of Open Access Journals (Sweden)

    Archita Das

    Full Text Available BACKGROUND: Cardiovascular disease (CVD remains one of the major killers in modern society. One strong risk factor of CVD is cigarette smoking that causes myocardial injury and leads to the genesis of pathological cardiovascular events. However, the exact toxic component(s of cigarette smoke (CS and its molecular and cellular mechanisms for causing myocardial injury leading to heart damage and its prevention are largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: Using a guinea pig model, here we show that chronic exposure to CS produces myocardial injury that is prevented by vitamin C. Male guinea pigs were fed either vitamin C-deficient (0.5 mg/day or vitamin C-sufficient (15 mg/day diet and subjected to CS exposure from 5 Kentucky Research cigarettes (3R4F/day (6 days/week in a smoke chamber up to 8 weeks. Pair-fed sham controls were subjected to air exposure instead of CS exposure under similar conditions. Myocardial injury was produced in CS-exposed marginal vitamin C-deficient guinea pigs as evidenced by release of cardiac Troponin-T and I in the serum, oxidative stress, inflammation, apoptosis, thrombosis and collagen deposition in the myocardium. Treatment of rat cardiomyocyte cells (H9c2 in vitro and guinea pigs in vivo with p-benzoquinone (p-BQ in amounts derived from CS revealed that p-BQ was a major factor responsible for CS-induced myocardial damage. A moderately large dose of vitamin C (15 mg/day prevented CS/p-BQ-induced myocardial injury. Population based studies indicated that plasma vitamin C levels of smokers without disease were significantly lower (p = 0,0000 than that of non-smokers. Vitamin C levels of CS-related cardiovascular patients were further lower (p = 0.0000 than that of smokers without disease. CONCLUSIONS/SIGNIFICANCE: The results indicate that dietary supplementation of vitamin C may be a novel and simple therapy for the prevention of pathological cardiovascular events in habitual smokers.

  2. Epigenetic Regulation of Placental "NR3C1": Mechanism Underlying Prenatal Programming of Infant Neurobehavior by Maternal Smoking?

    Science.gov (United States)

    Stroud, Laura R.; Papandonatos, George D.; Salisbury, Amy L.; Phipps, Maureen G.; Huestis, Marilyn A.; Niaura, Raymond; Padbury, James F.; Marsit, Carmen J.; Lester, Barry M.

    2016-01-01

    Epigenetic regulation of the placental glucocorticoid receptor gene ("NR3C1") was investigated as a mechanism underlying links between maternal smoking during pregnancy (MSDP) and infant neurobehavior in 45 mother-infant pairs (49% MSDP-exposed; 52% minorities; ages 18-35). The Neonatal Intensive Care Unit (NICU) Network Neurobehavioral…

  3. Grid-Connected Distributed Generation: Compensation Mechanism Basics

    Energy Technology Data Exchange (ETDEWEB)

    Aznar, Alexandra Y [National Renewable Energy Laboratory (NREL), Golden, CO (United States); ; ; ; Zinaman, Owen R [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-10-02

    This short report defines compensation mechanisms for grid-connected, behind-the-meter distributed generation (DG) systems as instruments that comprise three core elements: (1) metering and billing arrangements, (2) sell rate design, and (3) retail rate design. This report describes metering and billing arrangements, with some limited discussion of sell rate design. We detail the three possible arrangements for metering and billing of DG: net energy metering (NEM); buy all, sell all; and net billing.

  4. Tobacco Smoke: Involvement of Reactive Oxygen Species and Stable Free Radicals in Mechanisms of Oxidative Damage, Carcinogenesis and Synergistic Effects with Other Respirable Particles

    Directory of Open Access Journals (Sweden)

    Konstantinos Fiotakis

    2009-02-01

    Full Text Available Tobacco smoke contains many toxic, carcinogenic and mutagenic chemicals, as well as stable and unstable free radicals and reactive oxygen species (ROS in the particulate and the gas phase with the potential for biological oxidative damage. Epidemiological evidence established that smoking is one of the most important extrinsic factor of premature morbidity and mortality. The objective of this study was to investigate oxidative and carcinogenic mechanisms of tobacco and synergistic action with other respirable particles in the respiratory system of smokers. Electron Paramagnetic Resonance (EPR and spin- trapping techniques were used to study stable free radicals in the cigarette tar, and unstable superoxide anion (O2·- and hydroxyl (HO· radicals in the smoke Results showed that the semiquinone radical system has the potential for redox recycling and oxidative action. Further, results proved that aqueous cigarette tar (ACT solutions can generate adducts with DNA nucleobases, particularly the mutagenic 8-hydroxy-2’-deoxyguanosine (a biomarker for carcinogenesis.Also, we observed synergistic effects in the generation of HO·, through the Fenton reaction, with environmental respirable particles (asbestos fibres, coal dust, etc. and ambient particulate matter (PM, such as PM10, PM2.5 and diesel exhaust particles (DEP. The highest synergistic effects was observed with the asbestos fibres (freshly grounded, PM2.5 and DEP. Finally, we discuss results from our previous study of conventional cellulose acetate filters and “bio-filters” with hemoglobin impregnated activated carbon, which showed that these filters do not substantially alter the free radical content of smoke in the particulate and in the gaseous phase.

  5. Operating experience with the Harwell thermo-mechanical generators

    International Nuclear Information System (INIS)

    Cooke-Yarborough, E.H.

    1980-06-01

    The Stirling-cycle thermo-mechanical generator (TMG) provides small amounts of electrical power continuously over long periods, while requiring much less fuel than other power sources running from hydrocarbon fuel or radio-isotopes. Two of these 25-watt generators, fuelled by propane, have been used to power the UK National Buoy on two successive missions. A total of more than three years experience at sea has now been accumulated. In addition, a 60-watt version has provided the power for a major lighthouse for more than a year. An early development version of the Thermo-mechanical Generator, adapted to run from the heat of a radio-isotope source, was loaded with strontium 90 titanate in October 1974 and has run continuously in the laboratory ever since. The improvements and changes found necessary in the course of 90,000 generator-hours of running time are described, and the improvements in operational performance and reliability which have resulted are outlined. (author)

  6. Mechanisms underlying mindfulness-based addiction treatment versus cognitive behavioral therapy and usual care for smoking cessation.

    Science.gov (United States)

    Spears, Claire Adams; Hedeker, Donald; Li, Liang; Wu, Cai; Anderson, Natalie K; Houchins, Sean C; Vinci, Christine; Hoover, Diana Stewart; Vidrine, Jennifer Irvin; Cinciripini, Paul M; Waters, Andrew J; Wetter, David W

    2017-11-01

    To examine cognitive and affective mechanisms underlying mindfulness-based addiction treatment (MBAT) versus cognitive-behavioral therapy (CBT) and usual care (UC) for smoking cessation. Participants in the parent study from which data were drawn (N = 412; 54.9% female; 48.2% African American, 41.5% non-Latino White, 5.4% Latino, 4.9% other; 57.6% annual income <$30,000) were randomized to MBAT (n = 154), CBT (n = 155), or UC (n = 103). From quit date through 26 weeks postquit, participants completed measures of emotions, craving, dependence, withdrawal, self-efficacy, and attentional bias. Biochemically confirmed 7-day smoking abstinence was assessed at 4 and 26 weeks postquit. Although the parent study did not find a significant treatment effect on abstinence, mixed-effects regression models were conducted to examine treatment effects on hypothesized mechanisms, and indirect effects of treatments on abstinence were tested. Participants receiving MBAT perceived greater volitional control over smoking and evidenced lower volatility of anger than participants in both other treatments. However, there were no other significant differences between MBAT and CBT. Compared with those receiving UC, MBAT participants reported lower anxiety, concentration difficulties, craving, and dependence, as well as higher self-efficacy for managing negative affect without smoking. Indirect effects of MBAT versus UC on abstinence occurred through each of these mechanisms. Whereas several differences emerged between MBAT and UC, MBAT and CBT had similar effects on several of the psychosocial mechanisms implicated in tobacco dependence. Results help to shed light on similarities and differences between mindfulness-based and other active smoking cessation treatments. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Generation Mechanism for Interlinked Flux Tubes on the Magnetopause

    Science.gov (United States)

    Farinas Perez, G.; Cardoso, F. R.; Sibeck, D.; Gonzalez, W. D.; Facskó, G.; Coxon, J. C.; Pembroke, A. D.

    2018-02-01

    We use a global magnetohydrodynamics simulation to analyze transient magnetic reconnection processes at the magnetopause. The solar wind conditions have been kept constant, and an interplanetary magnetic field with large duskward BY and southward BZ components has been imposed. Five flux transfer events (FTEs) with clear bipolar magnetic field signatures have been observed. We observed a peculiar structure defined as interlinked flux tubes (IFTs) in the first and fourth FTE, which had very different generation mechanisms. The first FTE originates as an IFTs and remains with this configuration until its final moment. However, the fourth FTE develops as a classical flux rope but changes its 3-D magnetic configuration to that of IFTs. This work studies the mechanism for generating IFTs. The growth of the resistive tearing instability has been identified as the cause for the first IFTs formation. We believe that the instability has been triggered by the accumulation of interplanetary magnetic field at the subsolar point where the grid resolution is very high. The evidence shows that two new reconnection lines form northward and southward of the subsolar region. The IFTs have been generated with all the classical signatures of a single flux rope. The other IFTs detected in the fourth FTE developed as a result of magnetic reconnection inside its complex and twisted magnetic fields, which leads to a change in the magnetic configuration from a flux rope of twisted magnetic field lines to IFTs.

  8. Reforming water to generate hydrogen using mechanical alloy

    International Nuclear Information System (INIS)

    Pena F, D. L.

    2016-01-01

    The objective of this research was to generate a hydrogen production system by means of mechanical milling, in which 0.1 g of magnesium were weighed using a volume of 300 μL for each water solvent (H 2 O) and methanol (CH 3 OH) in a container to start mechanical milling for 2, 4 and 6 h. Once the mechanical milling was finished, the hydrogen that was produced every two hours was measured to determine the appropriate milling time in the production, also in each period of time samples of the powders produced during the milling of Mg were taken, in this process we used characterization techniques such as: X-ray diffraction at an angle of 2θi 5 and 2θf 90 degrees and scanning electron microscopy, taking micrographs of 100, 500, 1000 and 5000 magnifications. According to the mechanical milling results hydrogen was obtained when using water, as well as with methanol. In the techniques of X-ray diffraction characterization different results were obtained before and after the milling, since by the diffractogram s is possible to observe how the magnesium to be put in the mechanical milling along with the water and methanol was diminishing to be transformed into hydroxide and magnesium oxide, as well as in the micrographs taken with scanning electron microscopy the change in the magnesium morphology to hydroxide and magnesium oxide is observed. (Author)

  9. Quit Smoking >

    Science.gov (United States)

    Quit smoking; Stop smoking; Quit smoking women; Stop smoking women easy way for women to stop smoking; Smoking effects on women; effects of smoking on women; effects of smoking in women; smoking side effects for women; quit smoking cigarettes; smoking cessation; smoking cessation women

  10. The Value Generating Mechanisms of Open Government Data

    DEFF Research Database (Denmark)

    Jetzek, Thorhildur

    2013-01-01

    social progress, to an interconnected, networked world of shared resources and co-creation. One of the trends driving this change is open government data. This paper presents a framework of four value generating mechanisms from use of OGD. The framework makes it easier to compare and communicate......Recent trends towards openness and technical connectivity have offered the ability to drive massive social and economic change; however they demand a redefinition of relationships. We have observed a move from a polarized world where companies operate in economic markets while governments drive...... different pathways to value generation, while highlighting the current tensions between the private/public and economic/social domains. Our proposition is that these tensions bring about possibilites for synergies and value enhancement....

  11. Analytical generation of the dynamical equations for mechanical manipulators

    Directory of Open Access Journals (Sweden)

    Geir Horn

    1995-07-01

    Full Text Available A package to generate the symbolic dynamic equations describing the relation between forces and movements for serial mechanical linkages with rigid constituents is presented. The relative movement between the rigid parts is assumed to be either a rotation about an axis or a translation along an axis. Two algorithms are implemented, a Lagrange-Euler method and a Newton-Euler method. The former can be used to solve both the inverse and the forward dynamics problems, while the latter requires fewer arithmetical operations but only allows solution of the inverse dynamics problem. Two test examples are presented, the double pendulum and the modified Stanford manipulator.

  12. Mechanisms of nanotoxicity: generation of reactive oxygen species.

    Science.gov (United States)

    Fu, Peter P; Xia, Qingsu; Hwang, Huey-Min; Ray, Paresh C; Yu, Hongtao

    2014-03-01

    Nanotechnology is a rapidly developing field in the 21(st) century, and the commercial use of nanomaterials for novel applications is increasing exponentially. To date, the scientific basis for the cytotoxicity and genotoxicity of most manufactured nanomaterials are not understood. The mechanisms underlying the toxicity of nanomaterials have recently been studied intensively. An important mechanism of nanotoxicity is the generation of reactive oxygen species (ROS). Overproduction of ROS can induce oxidative stress, resulting in cells failing to maintain normal physiological redox-regulated functions. This in turn leads to DNA damage, unregulated cell signaling, change in cell motility, cytotoxicity, apoptosis, and cancer initiation. There are critical determinants that can affect the generation of ROS. These critical determinants, discussed briefly here, include: size, shape, particle surface, surface positive charges, surface-containing groups, particle dissolution, metal ion release from nanometals and nanometal oxides, UV light activation, aggregation, mode of interaction with cells, inflammation, and pH of the medium. Copyright © 2014. Published by Elsevier B.V.

  13. Generation Mechanism of Alternans in Luo-Rudy Model

    Science.gov (United States)

    Kitajima, Hiroyuki; Ioka, Eri; Yazawa, Toru

    Electrical alternans is the alternating amplitude from beat to beat in the action potential of the cardiac cell. It has been associated with ventricular arrhythmias in many clinical studies; however, its dynamical mechanisms remain unknown. The reason is that we do not have realistic network models of the heart system. Recently, Yazawa clarified the network structure of the heart and the central nerve system in the crustacean heart. In this study, we construct a simple model of the heart system based on Yazawa’s experimental data. Using this model, we clarify that two parameters (the conductance of sodium ions and free concentration of potassium ions in the extracellular compartment) play the key roles of generating alternans. In particular, we clarify that the inactivation gate of the time-independent potassium channel is the most important parameter. Moreover, interaction between the membrane potential and potassium ionic currents is significant for generating alternate rhythms. This result indicates that if the muscle cell has problems such as channelopathies, there is great risk of generating alternans.

  14. Examining an underlying mechanism between perceived stress and smoking cessation-related outcomes.

    Science.gov (United States)

    Robles, Zuzuky; Garey, Lorra; Hogan, Julianna; Bakhshaie, Jafar; Schmidt, Norman B; Zvolensky, Michael J

    2016-07-01

    The mediational role of negative reinforcement smoking outcome expectancies in the relation between perceived stress and (1) perceived barriers to cessation, (2) severity of problematic symptoms during past quit attempts, and (3) smoking-specific experiential avoidance (AIS) was examined. Data were drawn from a baseline assessment of a larger clinical trial. Participants included 332 adult treatment-seeking smokers (47.3% female; Mage=38.45; SD=.50; age range: 18-65 years). Results indicated that perceived stress was indirectly related to perceived barriers to smoking cessation, severity of problematic symptoms during past quit attempts, and AIS through negative reinforcement outcome expectancies. These results were evident after accounting for the variance explained by gender, negative affectivity, and alternative outcome expectancies for smoking. The present findings suggest that smokers with greater perceived stress experience greater negative reinforcement smoking expectancies, which in turn, may be related to numerous processes involved in the maintenance of smoking. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. The Effects of Electronic Cigarette (ECIG-Generated Aerosol and Conventional Cigarette Smoke on the Mucociliary Transport Velocity (MTV Using the Bullfrog (R. catesbiana Palate Paradigm

    Directory of Open Access Journals (Sweden)

    Dominic L. Palazzolo

    2017-12-01

    Full Text Available Background: While ECIGs are under scrutiny concerning safety, particularly in reference to the physiological impact that aerosolized ECIG liquid (E-liquid may have on respiratory tissues, others believe that ECIGs are a “Harm Reduction” alternative to conventional cigarettes. Previous studies investigating ciliated respiratory epithelium indicate that smoking shortens cilia length, reduces cilia beat frequency and disrupts respiratory epithelium, which most likely contributes to the inhibition of mucocilliary clearance. Monitoring mucous clearance of respiratory tissues exposed to ECIG-generated aerosol or conventional cigarette smoke, as indexed by mucous transport velocity (MTV, is one way to gauge the impact aerosol and smoke have on the respiratory tract. Therefore, we designed an experiment to test the effect of ECIG-generated aerosol and smoke on MTV using the frog palate paradigm.Methods: Peristaltic pumps transport ECIG-generated aerosol and conventional cigarette smoke into custom-made chambers containing excised bullfrog palates. MTVs were determined before exposure, immediately after exposure and approximately 1 day following exposure. MTVs were also determined (at the same time points for palates exposed to air (control. Surface and cross sectional SEM images of palates from all three groups were obtained to support MTV data.Results: The results indicate that ECIG-generated aerosol has a modest inhibitory effect (p < 0.05 on MTV 1 day post-exposure (0.09 ± 0.01 compared to control MTV (0.16 ± 0.03 mm/s. In contrast, smoke completely inhibits MTV from 0.14 ± 0.03 mm/s immediately before exposure to 0.00 mm/sec immediately after exposure and the MTV is unable to recover 1 day later. SEM images of control palates and palates exposed to ECIG-generated aerosol both show cilia throughout their epithelial surface, while some areas of palates exposed to smoke are completely devoid of cilia. Additionally, the epithelial thickness of

  16. Mechanisms of polymer degradation using an oxygen plasma generator

    Science.gov (United States)

    Colony, Joe A.; Sanford, Edward L.

    1987-01-01

    An RF oxygen plasma generator was used to produce polymer degradation which appears to be similar to that which has been observed in low Earth orbit. Mechanisms of this type of degradation were studied by collecting the reaction products in a cryogenic trap and identifying the molecular species using infrared, mass spectral, and X-ray diffraction techniques. No structurally dependent species were found from Kapton, Teflon, or Saran polymers. However, very reactive free radical entities are produced during the polymer degradation, as well as carbon dioxide and water. Reactions of the free radicals with the glass reaction vessel, with copper metal in the cold trap, and with a triphenyl phosphate scavenger in the cold trap, demonstrated the reactivity of the primary products.

  17. Effectiveness of levodropropizine against cigarette smoke-induced airway hyperreactivity: possible mechanism.

    Science.gov (United States)

    Daffonchio, L; Hernandez, A; Melillo, G; Clavenna, G; Omini, C

    1993-04-01

    We verified the possible effect of the new antitussive drug levodropropizine on airway hyperreactivity and lung inflammation induced by cigarette smoke exposure in anaesthetized guinea-pigs. Levodropropizine, administered by aerosol at 25 mg/ml for 30 s completely prevented smoke induced airway hyperreactivity. The protective effect was early in onset (3 min) and lasted up to 30 min. The same dose of codeine, administered in the form of an aerosol, decreased the increase in airway responsiveness induced by smoke inhalation slightly but not significantly. In parallel with the functional results, levodropropizine also inhibited the recruitment of inflammatory cells triggered by smoke exposure within the airway lumen. When levodropropizine was administered i.v. to anaesthetized guinea-pigs, it reduced the bronchocontractile effect of capsaicin dose-dependently, whereas it was without effect against substance P-induced bronchoconstriction. These data demonstrate the ability of levodropropizine to counteract the hyperreactive phenomenon and the associated inflammatory event induced by cigarette smoke exposure, an effect which might depend on its capacity to modulate the activation of the peptidergic system.

  18. Mechanism and modulation of terahertz generation from a semimetal - graphite

    Science.gov (United States)

    Ye, Tong; Meng, Sheng; Zhang, Jin; E, Yiwen; Yang, Yuping; Liu, Wuming; Yin, Yan; Wang, Li

    2016-01-01

    Semi-metals might offer a stronger interaction and a better confinement for terahertz wave than semiconductors, while preserve tunability. Particularly, graphene-based materials are envisioned as terahertz modulators, filters and ultra-broadband sources. However, the understanding of terahertz generation from those materials is still not clear, thus limits us recognizing the potential and improving device performances. Graphite, the mother material of graphene and a typical bulk semi-metal, is a good system to study semi-metals and graphene-based materials. Here we experimentally modulate and maximize the terahertz signal from graphite surface, thus reveal the mechanism - surface field driving photon induced carriers into transient current to radiate terahertz wave. We also discuss the differences between graphite and semiconductors; particularly graphite shows very weak temperature dependency from room temperature to 80 °C. Above knowledge will help us understand terahertz generations, achieve maximum output and electric modulation, in semi-metal or graphene based devices. PMID:26972818

  19. Organometallic rotaxane dendrimers with fourth-generation mechanically interlocked branches

    Science.gov (United States)

    Wang, Wei; Chen, Li-Jun; Wang, Xu-Qing; Sun, Bin; Li, Xiaopeng; Zhang, Yanyan; Shi, Jiameng; Yu, Yihua; Zhang, Li; Liu, Minghua; Yang, Hai-Bo

    2015-01-01

    Mechanically interlocked molecules, such as catenanes, rotaxanes, and knots, have applications in information storage, switching devices, and chemical catalysis. Rotaxanes are dumbbell-shaped molecules that are threaded through a large ring, and the relative motion of the two components along each other can respond to external stimuli. Multiple rotaxane units can amplify responsiveness, and repetitively branched molecules—dendrimers—can serve as vehicles for assembly of many rotaxanes on single, monodisperse compounds. Here, we report the synthesis of higher-generation rotaxane dendrimers by a divergent approach. Linkages were introduced as spacer elements to reduce crowding and to facilitate rotaxane motion, even at the congested periphery of the compounds up to the fourth generation. The structures were characterized by 1D multinuclear (1H, 13C, and 31P) and 2D NMR spectroscopy, MALDI-TOF-MS, gel permeation chromatography (GPC), and microscopy-based methods including atomic force microscopy (AFM) and transmission electron microscopy (TEM). AFM and TEM studies of rotaxane dendrimers vs. model dendrimers show that the rotaxane units enhance the rigidity and reduce the tendency of these assemblies to collapse by self-folding. Surface functionalization of the dendrimers with ferrocenes as termini produced electrochemically active assemblies. The preparation of dendrimers with a well-defined topological structure, enhanced rigidity, and diverse functional groups opens previously unidentified avenues for the application of these materials in molecular electronics and materials science. PMID:25902491

  20. The gluon mass generation mechanism: A concise primer

    Science.gov (United States)

    Aguilar, A. C.; Binosi, D.; Papavassiliou, J.

    2016-04-01

    We present a pedagogical overview of the nonperturbative mechanism that endows gluons with a dynamical mass. This analysis is performed based on pure Yang-Mills theories in the Landau gauge, within the theoretical framework that emerges from the combination of the pinch technique with the background field method. In particular, we concentrate on the Schwinger-Dyson equation satisfied by the gluon propagator and examine the necessary conditions for obtaining finite solutions within the infrared region. The role of seagull diagrams receives particular attention, as do the identities that enforce the cancellation of all potential quadratic divergences.We stress the necessity of introducing nonperturbative massless poles in the fully dressed vertices of the theory in order to trigger the Schwinger mechanism, and explain in detail the instrumental role of these poles in maintaining the Becchi-Rouet-Stora-Tyutin symmetry at every step of the mass-generating procedure. The dynamical equation governing the evolution of the gluon mass is derived, and its solutions are determined numerically following implementation of a set of simplifying assumptions. The obtained mass function is positive definite, and exhibits a power law running that is consistent with general arguments based on the operator product expansion in the ultraviolet region. A possible connection between confinement and the presence of an inflection point in the gluon propagator is briefly discussed.

  1. Steam Generator Analysis Tools and Modeling of Degradation Mechanisms

    International Nuclear Information System (INIS)

    Yetisir, M.; Pietralik, J.; Tapping, R.L.

    2004-01-01

    The degradation of steam generators (SGs) has a significant effect on nuclear heat transport system effectiveness and the lifetime and overall efficiency of a nuclear power plant. Hence, quantification of the effects of degradation mechanisms is an integral part of a SG degradation management strategy. Numerical analysis tools such as THIRST, a 3-dimensional (3D) thermal hydraulics code for recirculating SGs; SLUDGE, a 3D sludge prediction code; CHECWORKS a flow-accelerated corrosion prediction code for nuclear piping, PIPO-FE, a SG tube vibration code; and VIBIC and H3DMAP, 3D non-linear finite-element codes to predict SG tube fretting wear can be used to assess the impacts of various maintenance activities on SG thermal performance. These tools are also found to be invaluable at the design stage to influence the design by determining margins or by helping the designers minimize or avoid known degradation mechanisms. In this paper, the aforementioned numerical tools and their application to degradation mechanisms in CANDU recirculating SGs are described. In addition, the following degradation mechanisms are identified and their effect on SG thermal efficiency and lifetime are quantified: primary-side fouling, secondary-side fouling, fretting wear, and flow-accelerated corrosion (FAC). Primary-side tube inner diameter fouling has been a major contributor to SG thermal degradation. Using the results of thermalhydraulic analysis and field data, fouling margins are calculated. Individual effects of primary- and secondary-side fouling are separated through analyses, which allow station operators to decide what type of maintenance activity to perform and when to perform the maintenance activity. Prediction of the fretting-wear rate of tubes allows designers to decide on the number and locations of support plates and U-bend supports. The prediction of FAC rates for SG internals allows designers to select proper materials, and allows operators to adjust the SG maintenance

  2. Mechanized inspection of steam generator components during manufacture

    International Nuclear Information System (INIS)

    Otte, H.-J.; Leupoldt, K.; Meister, W.

    2009-01-01

    Steam Generator (SG) parts are intensively inspected by UT in the course of the manufacturing process. These inspections - mostly performed manually using different codes - are time consuming and call for a sophisticated documentation, figuring part of the life time documentation package. In order to reduce time and costs mechanized inspection equipment is introduced, combining short inspection times, avoiding influence of the human factor and providing proper electronic storage of all inspection results prepared for comparison with data generated during in-service inspection. Since 2001 Cegelec delivered various UT systems for gas turbine disks and rotor ends called SIRO-MAN. Within only a few years the majority of important providers of such components successfully switched from manual inspection to mechanized inspection following the requirements of manufacturers like ALSTOM, GE and Siemens. The SIRO-MAN is now adapted to the needs of mechanized inspection of SG components. The inspection is performed on the products during rotation around the vertical axis. The multi - probe assemblies are manoeuvred on the products by a manipulator system backed by a NC control unit. Acoustic coupling of UT probes to the product surface is performed with oil or water in a closed circuit. UT and - if requested ET - data along with position information of the probe assembly provided by the control unit are acquired, processed and evaluated by an UT / ET electronic system delivered by either Olympus or ZETEC. As performed already on rotor ends a sequence of inspections using different parameter settings can be programmed with simple means (Teach In) so that such inspection sequence can be executed without operating personnel. Probe assemblies allow for individual operation of probes out of the probe assembly according to the individual needs. Conventional UT and phased array applications or combination of both techniques can be provided. The UT / ET electronic equipment offers

  3. A dynamic smoke generation and nose-only inhalation exposure system for rats: preliminary results from studies of selected transportation materials.

    Science.gov (United States)

    Sun, Lei; Zhao, Xiaolong; Li, Daibo; Cai, Ying; An, Hui; Wang, Tao; Cui, Zhihong; Yang, Huan; Han, Fei; Ao, Lin; Liu, Jinyi; Cao, Jia

    2014-12-01

    Smoke inhalation injury is the main cause of fatalities for fire victims. Understanding in the pathophysiology of the injury has not been fully explored in recent years. To further explore the pathophysiological mechanism, a dynamic and controllable animal model is necessary. To develop a rat model of smoke inhalation injury to simulate human victims in air-restricted vehicle cabin fires. Smoke concentration, including CO, O2, VOCs and smoke temperature under different combustion conditions, were detected. Levels of COHb, respiratory function, lung wet-to-dry weight ratio and protein concentration in BALF and blood were measured. Pathological evaluations of lung in tissues were conducted at 1, 6, 24 and 48 h post-exposure. Smoke concentration rose with the increase of combustion temperature and decrease of oxygen flow. Further, 215 kinds of VOCs in the smoke were detected, and the concentrations of benzene, methylbenzene, ethylbenzene, dimethylbenzene, phenylethylene and trimethylbenzene was 32.93, 402.06, 764.03, 113.73, 1006.61 and 89.28 mg/m(3), respectively. Significant hypoxemia and CO poisoning occurred in rats. The FCOHb after exposure for 14 min immediately rose to (44.2 ± 12.3) % and then gradually decrease to a normal level at 300 min post-exposure. At 24 h post-exposure, Penh increased significantly (p smoke inhalation group. In summary, the novel rat model of smoke inhalation injury system used in the study is dynamic and controllable, and appropriate for use in smoke inhalation injury studies of air-restricted cabins in vehicles.

  4. The effect of varenicline and nicotine patch on smoking rate and satisfaction with smoking: an examination of the mechanism of action of two pre-quit pharmacotherapies.

    Science.gov (United States)

    Lu, Wenying; Chappell, Kate; Walters, Julia A E; Jacobson, Glenn A; Patel, Rahul; Schüz, Natalie; Ferguson, Stuart G

    2017-07-01

    In recent years, there has been growing research interest in using nicotine replacement medications to aid smoking reduction prior to a quit attempt. Gaining a better understanding of how treatments influence smoking reduction may allow for better tailoring of treatments and, ultimately, better cessation outcomes. The objective of the current study was to test the effects of the pre-quit use of varenicline and nicotine patch on smoking rate and satisfaction with smoking. All participants were required to attend up to five study visit sections. Participants (n = 213) who were interested in quitting were randomised (open-label) to receive either pre-quit patch or varenicline (both treatments started 2 weeks prior to an assigned quit day, followed by 10 weeks post-quit) or standard patch (10 weeks starting from an assigned quit day). Participants used modified smartphones to monitor their smoking in real time for 4 weeks. Participants in the two pre-quit treatment groups reported significant reductions in both their satisfaction with smoking (p < 0.001) and smoking rate (p < 0.001) from baseline to the end of pre-quit period; participants in the standard patch group did not. The observed reduction of smoking rate was associated with the satisfaction with smoking (p < 0.01), although the mediation effect of satisfaction was small. Pre-quit treatment caused reductions in satisfaction with smoking and smoking rate. Satisfaction was associated with changes in smoking rate, but the relationship was weak. As such, monitoring reductions in satisfaction do not appear to be a viable method of evaluating responsiveness to treatment.

  5. Thermal mechanical analysis of applications with internal heat generation

    Science.gov (United States)

    Govindarajan, Srisharan Garg

    control blade, spatial variations in temperature within the control blade occur from the non-uniform heat generation within the BORAL as a result of the non-uniform thermal neutron flux along the longitudinal direction when the control blade is partially withdrawn. There is also variation in the heating profile through the thickness and about the circumferential width of the control blade. Mathematical curve-fits are generated for the non-uniform volumetric heat generation profile caused by the thermal neutron absorption and the functions are applied as heating conditions within a finite element model of the control blade built using the commercial finite element code Abaqus FEA. The finite element model is solved as a fully coupled thermal mechanical problem as in the case of the annular target. The resulting deflection is compared with the channel gap to determine if there is a significant risk of the control blade binding during reactor operation. Hence, this dissertation will consist of two sections. The first section will seek to present the thermal and structural safety analyses of the annular targets for the production of molybdenum-99. Since there hasn't been any detailed, documented, study on these annular targets in the past, the work complied in this dissertation will help to understand the thermal-mechanical behavior and failure margins of the target during in-vessel irradiation. As the work presented in this dissertation provides a general performance analysis envelope for the annular target, the tools developed in the process can also be used as useful references for future analyses that are specific to any reactor. The numerical analysis approach adopted and the analytical models developed, can also be applied to other applications, outside the Mo-99 project domain, where internal heat generation exists such as in electronic components and nuclear reactor control blades. The second section will focus on estimating the thermally induced deflection and hence

  6. Association of homocysteine and smoking with cerebral microemboli in patients with mechanical heart valves: a transcranial Doppler study.

    Science.gov (United States)

    Mattia, Alicia; Azarpazhooh, M Reza; Munoz, Claudio; Bogiatzi, Chrysi; Quantz, Mackenzie A; Spence, J David

    2017-12-01

    Microembolic signals (MES) on transcranial Doppler (TCD) predict stroke and cognitive decline. Plasma levels of total homocysteine (tHcy), a prothrombotic factor, are higher in patients with microemboli in carotid stenosis and in patients with paradoxical embolism. In this study we assessed the association between the level of tHcy and the number of MES in patients with mechanical heart valves (MHVs). TCD monitoring was performed to detect MES before and after breathing 100% oxygen and repeated every 2-4 weeks up to six times. Twenty-five patients with MHVs (mean age: 63.60±10.15 years) participated in this study; 15 were men (66.47±7.25 years) and 10 were women (59.30±12.60 years). In total, there were 126 study visits. In multiple regression, higher tHcy was associated with more MES in both preoxygenation (OR 1.34 (95% CI 1.07 to 1.68, P=0.009)) and postoxygenation (OR 1.40 (95% CI 1.07 to 1.83, P=0.01)) phases. Current smoking and the length of time between the operation and monitoring also correlated with a higher number of MES before and after breathing oxygen, particularly in women. Higher tHcy and smoking were associated with a higher MES count in both preoxygenation and postoxygenation phases. Because smoking can be stopped and hyperhomocysteinaemia is treatable, these are clinically important findings.

  7. Microfluidic droplet generator with controlled break-up mechanism

    KAUST Repository

    Gonzalez, David Conchouso

    2017-04-13

    Droplet generation devices and systems that parallelize droplet generation devices are provided. The droplet generation devices can include a symmetric block-and-break system and a tapered droplet generation zone. The symmetric block-and-break system can include a pair of break channels and a pair of bypass channels symmetrically arranged with respect to the dispersed-phase input channel and the output channel. The droplet generation devices can generate monodisperse droplets with a predefined volume over a range of flow rates, pressures, and fluid properties. The droplet generation devices are therefore capable of parallelization to achieve large-capacity droplet generation, e.g. greater than 1 L/hr, with small overall coefficients of variation.

  8. Mechanism of cigarette smoke condensate-induced acute inflammatory response in human bronchial epithelial cells

    Directory of Open Access Journals (Sweden)

    Mohapatra Shyam S

    2002-07-01

    Full Text Available Abstract Background To demonstrate the involvement of tobacco smoking in the pathophysiology of lung disease, the responses of pulmonary epithelial cells to cigarette smoke condensate (CSC — the particulate fraction of tobacco smoke — were examined. Methods The human alveolar epithelial cell line A549 and normal human bronchial epithelial cells (NHBEs were exposed to 0.4 μg/ml CSC, a concentration that resulted in >90% cell survival and Results NHBEs exposed to CSC showed increased expression of the inflammatory mediators sICAM-1, IL-1β, IL-8 and GM-CSF, as determined by RT-PCR. CSC-induced IL-1β expression was reduced by PD98059, a blocker of mitogen-actived protein kinase (MAPK kinase (MEK, and by PDTC, a NFκB inhibitor. Analysis of intracellular signaling pathways, using antibodies specific for phosphorylated MAPKs (extracellular signal-regulated kinase [ERK]-1/2, demonstrated an increased level of phosphorylated ERK1/2 with increasing CSC concentration. Nuclear localization of phosphorylated ERK1/2 was seen within 30 min of CSC exposure and was inhibited by PD98059. Increased phosphorylation and nuclear translocation of IκB was also seen after CSC exposure. A549 cells transfected with a luciferase reporter plasmid containing a NFκB-inducible promoter sequence and exposed to CSC (0.4 μg/ml or TNF-α (50 ng/ml had an increased reporter activity of approximately 2-fold for CSC and 3.5-fold for TNF-α relative to untreated controls. Conclusion The acute phase response of NHBEs to cigarette smoke involves activation of both MAPK and NFκB.

  9. Analysis of mechanical behavior and hysteresis heat generating mechanism of PDM motor

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Changshuai; Zhu, Xiaohua; Tang, Liping [Southwest Petroleum University, Chengdu (China); Deng, Juan [Avic Chengdu Engine (Group) Co.,Ltd, Chengdu (China)

    2017-03-15

    Positive displacement motor (PDM), which is prone to high temperature fatigue failure, can be weakened in its application in deep and superdeep well. In order to study the forced state, deformation regularity and thermal hysteresis of PDM motor, the paper established the three-dimensional thermal-mechanical coupled Finite element model (FEM). Based on the theoretical research, experimental study and numerical simulation, the study found that the displacement of stator lining shows a sinusoidal variation under internal pressure, when adapting the general form of sine function to fitting inner contour line deformation function. Then the paper analyzed the hysteresis heat generating mechanism of the motor, learning that hysteresis thermogenous of stator lining occurs due to the viscoelastic of rubber material and cyclic loading of stator lining. A heartburn happens gradually in the center of the thickest part of the stator lining as temperature increases, which means work efficiency and service life of PDM will be decreased when used in deep or superdeep well. In this paper, we established a theory equation for the choice of interference fit and motor line type optimization design, showing hysteresis heat generating analyzing model and method are reasonable enough to significantly improve PDM’s structure and help better use PDM in deep and surdeep well.

  10. Tristetraprolin Down-Regulation Contributes to Persistent TNF-Alpha Expression Induced by Cigarette Smoke Extract through a Post-Transcriptional Mechanism

    Science.gov (United States)

    Cheng, Ming-Liang; Zhang, Quan; Mu, Mao; Li, Hong; Luo, Yuan; Liang, Yue-Dong; Luo, Xin-Hua; Gao, Chang-Qing; Jackson, Patricia L.; Wells, J. Michael; Zhou, Yong; Hu, Meng; Cai, Guoqiang; Thannickal, Victor J.; Steele, Chad; Blalock, J. Edwin; Han, Xiaosi; Chen, Ching-Yi; Ding, Qiang

    2016-01-01

    Rationale Tumor necrosis factor-alpha (TNF-α) is a potent pro-inflammatory mediator and its expression is up-regulated in chronic obstructive pulmonary disease (COPD). Tristetraprolin (TTP) is implicated in regulation of TNF-α expression; however, whether TTP is involved in cigarette smoke-induced TNF-α expression has not been determined. Methods TTP expression was examined by western blot analysis in murine alveolar macrophages and alveolar epithelial cells challenged without or with cigarette smoke extract (CSE). TNF-α mRNA stability, and the decay of TNF-α mRNA, were determined by real-time quantitative RT-PCR. TNF-α protein levels were examined at the same time in these cells. To identify the molecular mechanism involved, a construct expressing the human beta-globin reporter mRNA containing the TNF-α 3’-untranslated region was generated to characterize the TTP targeted site within TNF-α mRNA. Results CSE induced TTP down-regulation in alveolar macrophages and alveolar epithelial cells. Reduced TTP expression resulted in significantly increased TNF-α mRNA stability. Importantly, increased TNF-α mRNA stability due to impaired TTP function resulted in significantly increased TNF-α levels in these cells. Forced TTP expression abrogated the increased TNF-α mRNA stability and expression induced by CSE. By using the globin reporter construct containing TNF-α mRNA 3’-untranslated region, the data indicate that TTP directly targets the adenine- and uridine-rich region (ARE) of TNF-α mRNA and negatively regulates TNF-α expression at the post-transcriptional level. Conclusion The data demonstrate that cigarette smoke exposure reduces TTP expression and impairs TTP function, resulting in significantly increased TNF-α mRNA stability and excessive TNF-α expression in alveolar macrophages and epithelial cells. The data suggest that TTP is a novel post-transcriptional regulator and limits excessive TNF-α expression and inflammatory response induced by

  11. HPLC-MS Determination of Acrolein and Acetone Generated from 13C3 -Labeled Glycerol Added to Cigarette Tobacco Using Two Machine-Smoking Regimes

    Directory of Open Access Journals (Sweden)

    Yip SH

    2014-12-01

    Full Text Available The extent of blend glycerol degradation in a burning cigarette to form acrolein and acetone has been quantitatively determined by the addition of glycerol-13C3 to three styles of a leading commercial cigarette brand. Multiple Cambridge pads soaked with a solution of 2,4-dinitrophenylhydrazine (DNPH were employed to trap hydrazone derivatives of low molecular weight carbonyl compounds in both mainstream and sidestream smoke. High performance liquid chromatography coupled with negative ion mass spectrometry was used to isolate DNPH derivatives of the volatile carbonyl products of combustion and to ascertain their concentration. Acrolein, acetone, and propionaldehyde were the principal compounds of interest. The DNPH derivatives of acrolein-13C3 and acetone-13C3 were independently synthesized, and they served as external standards for absolute quantitation. The cost of fully labeled propionaldehyde precluded its use in this study. The brand styles selected for study represent the cigarette design features that are most prevalent in the U.S. market today and afford a representative range of standardized “tar” yields (14, 10, and 5 mg/cig, respectively by the Cambridge Filter Method. The brand styles studied are part of a commercial cigarette brand family that does not contain additives to the tobacco blend, including glycerol. Mainstream smoke was generated by an automated smoking machine employing the standard Cambridge Filter Smoking Regime and a more intense regime requiring larger, more frequent puffs and 100% vent blocking that is specified for regulatory purposes by the Canadian federal government. The research indicated that only a small fraction of added glycerol (~0.25%-0.30%, w/w was converted to the two compounds of interest, with the larger portion generally observed in sidestream smoke. Less than 0.1% of the added glycerol was converted to acrolein in mainstream smoke for all cigarette designs and smoking regimes studied.

  12. Parental smoking during pregnancy and total and abdominal fat distribution in school-age children: The Generation R Study

    NARCIS (Netherlands)

    B. Durmus (Busra); D.H.M. Heppe (Denise); H.R. Taal (Rob); R. Manniesing (Rashindra); H. Raat (Hein); A. Hofman (Albert); E.A.P. Steegers (Eric); R. Gaillard (Romy); V.W.V. Jaddoe (Vincent)

    2014-01-01

    textabstractObjective: Fetal smoke exposure may influence growth and body composition later in life. We examined the associations of maternal and paternal smoking during pregnancy with total and abdominal fat distribution in school-age children. Methods: We performed a population-based prospective

  13. Quit Smoking

    Science.gov (United States)

    ... Quit Smoking Print This Topic En español Quit Smoking Browse Sections The Basics Overview Secondhand Smoke How ... to be active with your family and friends. Smoking hurts almost every part of the body. Smoking ...

  14. [Smoking and periodontal disease].

    Science.gov (United States)

    Shizukuishi, Satoshi

    2007-02-01

    Over the past 20 years, numerous investigations have demonstrated epidemiologically and biologically that smoking is one of the most significant risk factors with respect to the development and progression of periodontal disease. In terms of the mechanism via which smoking influences periodontitis progression, various factors contribute to the deleterious periodontal effects of smoking, including alteration of both microbial and host response factors. Furthermore, since it is well known that smoking is also a risk factor of osteoporosis, the combination of smoking with osteoporosis further enhances the risk of periodontal disease. Recent investigations reported that passive smoking exposure may be a risk factor of periodontal disease and may stimulate inflammatory responses of periodontal tissue.

  15. Nonlinear mechanism of tsunami wave generation by atmospheric disturbances

    OpenAIRE

    Pelinovsky, E.; Talipova, T.; Kurkin, A.; Kharif, C.

    2001-01-01

    The problem of tsunami wave generation by variable meteo-conditions is discussed. The simplified linear and nonlinear shallow water models are derived, and their analytical solutions for a basin of constant depth are discussed. The shallow-water model describes well the properties of the generated tsunami waves for all regimes, except the resonance case. The nonlinear-dispersive model based on the forced Korteweg-de Vries equation ...

  16. Social Capital and Smoking Behavior

    OpenAIRE

    Lorenzo Rocco; Beatrice d'Hombres

    2014-01-01

    In this paper, we explore one mechanism that may underlie the negative relationship between social capital and smoking: whether social capital strengthens the effect of anti-smoking regulations. We use data on smoking behaviors collected immediately before and after the implementation of smoking bans in public places in Germany in order to determine whether the impact of these bans on smoking prevalence and intensity is greater among individuals richer in social capital. We find that smoking ...

  17. Smoke detection

    Energy Technology Data Exchange (ETDEWEB)

    Warmack, Robert J. Bruce; Wolf, Dennis A.; Frank, Steven Shane

    2017-10-17

    Various apparatus and methods for smoke detection are disclosed. In one embodiment, a method of training a classifier for a smoke detector comprises inputting sensor data from a plurality of tests into a processor. The sensor data is processed to generate derived signal data corresponding to the test data for respective tests. The derived signal data is assigned into categories comprising at least one fire group and at least one non-fire group. Linear discriminant analysis (LDA) training is performed by the processor. The derived signal data and the assigned categories for the derived signal data are inputs to the LDA training. The output of the LDA training is stored in a computer readable medium, such as in a smoke detector that uses LDA to determine, based on the training, whether present conditions indicate the existence of a fire.

  18. Smoke detection

    Science.gov (United States)

    Warmack, Robert J. Bruce; Wolf, Dennis A.; Frank, Steven Shane

    2015-10-27

    Various apparatus and methods for smoke detection are disclosed. In one embodiment, a method of training a classifier for a smoke detector comprises inputting sensor data from a plurality of tests into a processor. The sensor data is processed to generate derived signal data corresponding to the test data for respective tests. The derived signal data is assigned into categories comprising at least one fire group and at least one non-fire group. Linear discriminant analysis (LDA) training is performed by the processor. The derived signal data and the assigned categories for the derived signal data are inputs to the LDA training. The output of the LDA training is stored in a computer readable medium, such as in a smoke detector that uses LDA to determine, based on the training, whether present conditions indicate the existence of a fire.

  19. Smoking and Periodontal Diseases

    OpenAIRE

    Torkzaban; Khalili; Ziaei

    2013-01-01

    Context The aim of this review was to examine evidences for the association between smoking and periodontal disease, to discuss possible biological mechanisms whereby smoking may adversely affect the periodontium, and to consider the effect of smoking on periodontal treatment. Evidence Acquisition A web-based search in PubMed and Google Scholar was performed to identify publications regarding the effects of smoking on various aspe...

  20. Mechanisms of THz generation from silver nanoparticle and nanohole arrays

    NARCIS (Netherlands)

    Polyushkin, D.K.; Marton, I.; Racz, P.; Dombi, P.; Hendry, E.; Barnes, William Leslie

    2014-01-01

    We study THz pulses generated from plasmonic metal nanostructures under femtosecond illumination of near-IR light. We find two regimes of excitation, according to the order of the dependence of the THz fluence on the incident near-IR intensity: less then second order at low intensities, changing to

  1. Origin and generation mechanisms of geopressures in shale ...

    African Journals Online (AJOL)

    In the Niger Delta, Gulf of Mexico, and indeed worldwide, the generation of geopressure is often related to the sedimentation rate, while its dissipation depends on the hydrological properties of the sediments(that is porosity, permeability, etc).Geopressures influences many fluid related aspects of petroleum geology ...

  2. Full bundle mechanical cleaning of pressurized water reactor steam generators

    International Nuclear Information System (INIS)

    Reinhardt, M.; Lewis, G.

    1998-01-01

    An improved system for cleaning the upper bundle region of pressurized water reactor steam generators is now available. This system employs high pressure water jets to remove sludge and scale from tube and support plate surfaces and from the broach holes throughout the upper bundle region of steam generators. Benefits of sludge removal can include mitigation of the corrosion process, improvement of plant performance and increased operational stability. The cleaning equipment is installed through existing handholes in the tubesheet region and accesses the upper bundle through flow slots in the tube support plates. The system includes a Bulk Cleaning Head which directs high pressure water jets into the tube bundle, a Vertical Deployment System which delivers and positions the head at the desired locations in the upper bundle region, and a high pressure water pumping and sludge processing system. This paper describes the system, several key components, overall system operation, safety issues, and field use chronology. Specific performance issues that are discussed include the cleaning coverage achieved, the time required to clean a steam generator, and cleaning effectiveness. The Upper Bundle Hydraulic Cleaning System described in this paper is available for use in several types of steam generators

  3. Systems Biology Reveals Cigarette Smoke-Induced Concentration-Dependent Direct and Indirect Mechanisms That Promote Monocyte-Endothelial Cell Adhesion.

    Science.gov (United States)

    Poussin, Carine; Laurent, Alexandra; Peitsch, Manuel C; Hoeng, Julia; De Leon, Hector

    2015-10-01

    Cigarette smoke (CS) affects the adhesion of monocytes to endothelial cells, a critical step in atherogenesis. Using an in vitro adhesion assay together with innovative computational systems biology approaches to analyze omics data, our study aimed at investigating CS-induced mechanisms by which monocyte-endothelial cell adhesion is promoted. Primary human coronary artery endothelial cells (HCAECs) were treated for 4 h with (1) conditioned media of human monocytic Mono Mac-6 (MM6) cells preincubated with low or high concentrations of aqueous CS extract (sbPBS) from reference cigarette 3R4F for 2 h (indirect treatment, I), (2) unconditioned media similarly prepared without MM6 cells (direct treatment, D), or (3) freshly generated sbPBS (fresh direct treatment, FD). sbPBS promoted MM6 cells-HCAECs adhesion following I and FD, but not D. In I, the effect was mediated at a low concentration through activation of vascular inflammation processes promoted in HCAECs by a paracrine effect of the soluble mediators secreted by sbPBS-treated MM6 cells. Tumor necrosis factor α (TNFα), a major inducer, was actually shed by unstable CS compound-activated TNFα-converting enzyme. In FD, the effect was triggered at a high concentration that also induced some toxicity. This effect was mediated through an yet unknown mechanism associated with a stress damage response promoted in HCAECs by unstable CS compounds present in freshly generated sbPBS, which had decayed in D unconditioned media. Aqueous CS extract directly and indirectly promotes monocytic cell-endothelial cell adhesion in vitro via distinct concentration-dependent mechanisms. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. The effect of tobacco smoke exposure on the generation of reactive oxygen species and cellular membrane damage using co-culture model of blood brain barrier with astrocytes.

    Science.gov (United States)

    Seo, Seung-Beom; Choe, Eun Sang; Kim, Kwang-Sik; Shim, Soon-Mi

    2017-06-01

    Brain tissue is known to be vulnerable to the exposure by tobacco smoke. Tobacco smoke can induce generation of reactive oxygen species (ROS), causing inflammatory activity and blood-brain barrier (BBB) impairment. The aim of the present study was to investigate the effect of tobacco smoke on cell cytotoxicity, generation of ROS, and cellular membrane damage in astrocytes and BBB using a co-culture system. Cell viability of U373MG cells was reduced in a dose-dependent manner, ranging from 96.7% to 40.3% by tobacco smoke condensate (TSC). Cell viability of U373MG co-cultured with human brain microvascular endothelial cells (HBMECs) was 104.9% at the IC 50 value of TSC. Trans-epithelial electric resistance values drastically decreased 80% following 12-h incubation. The value was maintained until 48 h and then increased at 72-h incubation (85%). It then decreased to 75% at 120 h. Generation of ROS increased in a dose-dependent manner, ranging from 102.7% to 107.9%, when various concentrations of TSC (4-16 mg/mL) were administered to the U373MG monoculture. When TSC was added into U373MG co-cultured with HBMECs, production of ROS ranged from 101.7% to 102.6%, slightly increasing over 12 h. Maximum exposure-generated ROS of 104.8% was reached at 24 h. Cell cytotoxicity and oxidative stress levels in the U373MG co-culture model system with HBMECs were lower than U373MG monoculture. HBMECs effectively acted as a barrier to protect the astrocytes (U373MG) from toxicity of TSC.

  5. NREL Next Generation Drivetrain: Mechanical Design and Test Plan (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Keller, J.; Halse, C.

    2014-05-01

    The Department of Energy and industry partners are sponsoring a $3m project for design and testing of a 'Next Generation' wind turbine drivetrain at the National Renewable Energy Laboratory (NREL). This poster focuses on innovative aspects of the gearbox design, completed as part of an end-to-end systems engineering approach incorporating innovations that increase drivetrain reliability, efficiency, torque density and minimize capital cost.

  6. Working mechanisms of computer-tailored health education : evidence from smoking cessation

    NARCIS (Netherlands)

    Dijkstra, A.

    2005-01-01

    To further develop tailored interventions, their working mechanisms must be identified. In the present study, three tailored messages that each contained one potential working mechanism-personalization, adaptation or feedback-were compared with a standard information condition. Two hundred and two

  7. Mechanical Design of a Second Generation LHC IR Quadrupole

    International Nuclear Information System (INIS)

    Caspi, S.; Bartlett, S.E.; Dietderich, D.R.; Ferracin, P.; Gourlay, S.A.; Hafalia, R.R.; Hannaford, C.R.; Lietzke, A.F.; McInturff, A.D.; Sabbi, G.; Scanlan, R.M.

    2003-01-01

    One of the proposed options to increase the LHC luminosity is the replacement of the existing inner triplets at the Interaction Regions with new low-beta larger aperture quadrupoles operating at the same gradient. Lawrence Berkeley National Laboratory (LBNL) is carrying out preliminary studies of a large-bore Nb 3 Sn quadrupole. The mechanical design presents a support structure based on the use of keys and bladders without self-supporting collars. This technology has been proven effective in several successful common coil Nb 3 Sn dipoles built at LBNL, and it is for the first time applied to a cos(2(var t heta)) design. In this paper we present a detailed analysis of the quadrupole mechanical behavior, demonstrating the possibility of delivering, through this method, well-controlled coil precompression during assembly, cool-down and excitation. The study has been performed with the finite element program ANSYS

  8. Active oxygen generation as a possible mechanism of selenium toxicity.

    Science.gov (United States)

    Seko, Y; Imura, N

    1997-09-01

    Selenium plays an important role in scavenging active oxygen (AO) species as an essential constituent of glutathione peroxidase. On the other hand, several reports proposed a possible induction of toxic AO by selenium compounds in vitro. However, some of these experiments including ours, were revealed to conclude on the basis of experimental artifacts, and to have problems in the interpretation of data. Methods or principles so far used for the detection of AO species generated by selenium compound were measurement of chemiluminescence from lucigenin or luminol by AO species, the spectrophotometric analysis of reduction of ferricytochrome c or nitroblue tetrazolium (NBT) by superoxide anion (O2-), electron spin resonance (ESR) spectra using dimethylpyrroline oxide (DMPO) as a spin trapping agent, the deoxyribose decomposition by hydroxyl radical (HO.), the salicylate hydroxylation by HO., and the strand breakage of DNA by AO. Many of these methods together with their principles seem to have some defects which prevent clear conclusion as stated below. (i) Lucigenin was found to mediate the formation of O2- in the presence of selenite and reduced glutathione (GSH). Therefore, lucigenin is not a suitable reagent. (ii) Luminol may also mediate O2- generation in the presence of HO.. (iii) ferricytochrome c can be reduced to ferrocytochrome c in the mixture of selenite and GSH in the absence of oxygen. Moreover, the spectrophotometric method is interfered by turbidity of elemental selenium formed under some conditions in the reaction mixture containing selenite and GSH. (iv) NBT is also reduced by selenium compounds in the absence of O2. (v) ESR signals of AO species were obtained in the reaction mixture containing selenite and GSH, or in the solution of hydrogen selenide in the presence of O2. However, selenide decomposed spin adduct of DMPO with HO. (DMPO-OH). Therefore, the intensity of the signals is not quantitative. (vi) CuZn-SOD is not necessarily a good tool to

  9. Curved mesh generation and mesh refinement using Lagrangian solid mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Persson, P.-O.; Peraire, J.

    2008-12-31

    We propose a method for generating well-shaped curved unstructured meshes using a nonlinear elasticity analogy. The geometry of the domain to be meshed is represented as an elastic solid. The undeformed geometry is the initial mesh of linear triangular or tetrahedral elements. The external loading results from prescribing a boundary displacement to be that of the curved geometry, and the final configuration is determined by solving for the equilibrium configuration. The deformations are represented using piecewise polynomials within each element of the original mesh. When the mesh is sufficiently fine to resolve the solid deformation, this method guarantees non-intersecting elements even for highly distorted or anisotropic initial meshes. We describe the method and the solution procedures, and we show a number of examples of two and three dimensional simplex meshes with curved boundaries. We also demonstrate how to use the technique for local refinement of non-curved meshes in the presence of curved boundaries.

  10. Tsunamis: stochastic models of occurrence and generation mechanisms

    Science.gov (United States)

    Geist, Eric L.; Oglesby, David D.

    2014-01-01

    The devastating consequences of the 2004 Indian Ocean and 2011 Japan tsunamis have led to increased research into many different aspects of the tsunami phenomenon. In this entry, we review research related to the observed complexity and uncertainty associated with tsunami generation, propagation, and occurrence described and analyzed using a variety of stochastic methods. In each case, seismogenic tsunamis are primarily considered. Stochastic models are developed from the physical theories that govern tsunami evolution combined with empirical models fitted to seismic and tsunami observations, as well as tsunami catalogs. These stochastic methods are key to providing probabilistic forecasts and hazard assessments for tsunamis. The stochastic methods described here are similar to those described for earthquakes (Vere-Jones 2013) and volcanoes (Bebbington 2013) in this encyclopedia.

  11. Evaluation on mechanical and corrosion properties of steam generator tubing materials

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Sup; Lee, Byong Whi; Lee, Sang Kyu; Lee, Young Ho; Kim, Jun Whan; Lee, Ju Seok; Kwon, Hyuk Sang; Kim, Su Jung [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1998-06-15

    Steam generator is one of the major components of nuclear reactor pressure boundary. It's main function os transferring heat which generated in the reactor to turbine generator through steam generator tube. In these days, steam generator tubing materials of operating plant are used Inconel 600 alloys. But according to the operation time, there are many degradation phenomena which included mechanical damage due to flow induced vibration and corrosion damage due to PWSCC, IGA/SCC and pitting etc. Recently Inconel 690 alloys are selected as new and replacement steam generator tubes for domestic nuclear power plant. But there are few study about mechanical and corrosion properties of Inconel 600 and 690. The objectives of this study is to evaluate and compare mechanical and corrosion propertied of steam generator tube materials.

  12. On the generation mechanism of ULF seismogenic electromagnetic emissions

    Science.gov (United States)

    Molchanov, O. A.; Hayakawa, M.

    Microfracturing electrification is suggested as a possible mechanism for explaining ULF electromagnetic emissions observed before and after the earthquakes. This effect appears as fast fluctuation of microcracks and leads to the origination of wideband electromagnetic noise. This noise dissipates outside the source region and produces ULF emissions on the ground surface with an upper cutoff frequency ˜1 Hz due to the skin depth attenuation. Each microcurrent results from charge relaxation during microcrack opening and depends on the time of opening and conductivity of the rock medium. The normal size distribution of microcracks, their fast opening and healing (intermittence), and average size progression due to stress corrosion are assumed. Using this model, it is possible to compare these theoretical explanations with the observational results with reference to the intensity, frequency spectrum and temporal development of ULF magnetic field variations.

  13. Smoking and Passive Smoking

    Directory of Open Access Journals (Sweden)

    Russell V. Luepker, MD, MS

    2016-09-01

    Full Text Available Objective: To review the literature on associations between cardiovascular diseases and tobacco use, including recent trends in smoking behaviors and clinical approaches for cessation of smoking. Methods: A literature review of recent scientific findings for smoking and cardiovascular diseases and recommendations for obtaining cessation. Results: Tobacco smoking is causally related to cardiovascular disease, with nearly a half million deaths annually attributed to cigarette smoking in the United States. The human, economic, medical, and indirect costs are enormous. Secondhand smoke as inhaled from the environment also plays an important role in the genesis of cardiovascular diseases. A recent trend in the use of e-cigarettes is noted particularly among youth. For children, prevention is the best strategy. For adult smokers, behavioral treatments, self-help approaches, and pharmacologic therapies are readily available. Clinicians can have a significant impact on patients’ smoking habits. Adding to individual strategies, regulatory community and public health approaches provide the potential for eliminating the use of tobacco. Conclusion: Tobacco smoke causes cardiovascular morbidity and death. Clinicians can play a role in preventing smoking and promoting cessation.

  14. The inhibitory mechanism of Cordyceps sinensis on cigarette smoke extract-induced senescence in human bronchial epithelial cells.

    Science.gov (United States)

    Liu, Ailing; Wu, Jinxiang; Li, Aijun; Bi, Wenxiang; Liu, Tian; Cao, Liuzhao; Liu, Yahui; Dong, Liang

    2016-01-01

    Cellular senescence is a state of irreversible growth arrest induced either by telomere shortening (replicative senescence) or stress. The bronchial epithelial cell is often injured by inhaled toxic substances, such as cigarette smoke. In the present study, we investigated whether exposure to cigarette smoke extract (CSE) induces senescence of bronchial epithelial cells; and Cordyceps sinensis mechanism of inhibition of CSE-induced cellular senescence. Human bronchial epithelial cells (16HBE cells) cultured in vitro were treated with CSE and/or C. sinensis. p16, p21, and senescence-associated-galactosidase activity were used to detect cellular senescence with immunofluorescence, quantitative polymerase chain reaction, and Western blotting. Reactive oxygen species (ROS), PI3K/AKT/mTOR and their phosphorylated proteins were examined to testify the activation of signaling pathway by ROS fluorescent staining and Western blotting. Then, inhibitors of ROS and PI3K were used to further confirm the function of this pathway. Cellular senescence was upregulated by CSE treatment, and C. sinensis can decrease CSE-induced cellular senescence. Activation of ROS/PI3K/AKT/mTOR signaling pathway was enhanced by CSE treatment, and decreased when C. sinensis was added. Blocking ROS/PI3K/AKT/mTOR signaling pathway can attenuate CSE-induced cellular senescence. CSE can induce cellular senescence in human bronchial epithelial cells, and ROS/PI3K/AKT/mTOR signaling pathway may play an important role in this process. C. sinensis can inhibit the CSE-induced senescence.

  15. Hazardous Compounds in Tobacco Smoke

    OpenAIRE

    Talhout, Reinskje; Schulz, Thomas; Florek, Ewa; van Benthem, Jan; Wester, Piet; Opperhuizen, Antoon

    2011-01-01

    Tobacco smoke is a toxic and carcinogenic mixture of more than 5,000 chemicals. The present article provides a list of 98 hazardous smoke components, based on an extensive literature search for known smoke components and their human health inhalation risks. An electronic database of smoke components containing more than 2,200 entries was generated. Emission levels in mainstream smoke have been found for 542 of the components and a human inhalation risk value for 98 components. As components w...

  16. A proposal for a dipole-generated BLUF domain mechanism

    Directory of Open Access Journals (Sweden)

    Tilo eMathes

    2015-11-01

    Full Text Available The resting and signaling structures of the blue-light sensing using flavin (BLUF photoreceptor domains are still controversially debated due to differences in the molecular models obtained by crystal and NMR structures. Photocycles for the given preferred structural framework have been established, but a unifying picture combining experiment and theory remains elusive. We summarize present work on the AppA BLUF domain from both experiment and theory. We focus on IR and UV/vis spectra, and to what extent theory was able to reproduce experimental data and predict the structural changes upon formation of the signaling state. We find that the experimental observables can be theoretically reproduced employing any structural model, as long as the orientation of the signaling essential Gln63 and its tautomer state are a choice of the modeler. We also observe that few approaches are comparative, e.g. by considering all structures in the same context. Based on recent experimental findings and a few basic calculations, we suggest the possibility for a BLUF activation mechanism that only relies on electron transfer and its effect on the local electrostatics, not requiring an associated proton transfer. In this regard, we investigate the impact of dispersion correction on the interaction energies arising from weakly bound amino acids.

  17. Variate generation for probabilistic fracture mechanics and fitness-for-service studies

    International Nuclear Information System (INIS)

    Walker, J.R.

    1987-01-01

    Atomic Energy of Canada Limited is conducting studies in Probabilistic Fracture Mechanics. These studies are being conducted as part of a fitness-for-service programme in support of CANDU reactors. The Monte Carlo analyses, which form part of the Probabilistic Fracture Mechanics studies, require that variates can be sampled from probability density functions. Accurate pseudo-random numbers are necessary for accurate variate generation. This report details the principles of variate generation, and describes the production and testing of pseudo-random numbers. A new algorithm has been produced for the correct performance of the lattice test for the independence of pseudo-random numbers. Two new pseudo-random number generators have been produced. These generators have excellent randomness properties and can be made fully machine-independent. Versions, in FORTRAN, for VAX and CDC computers are given. Accurate and efficient algorithms for the generation of variates from the specialized probability density functions of Probabilistic Fracture Mechanics are given. 38 refs

  18. Bacteria and smoke-water extract improve growth and induce the synthesis of volatile defense mechanisms in Vitis vinifera L.

    Science.gov (United States)

    Salomon, María Victoria; Piccoli, Patricia; Funes Pinter, Iván; Stirk, Wendy Ann; Kulkarni, Manoj; van Staden, Johannes; Bottini, Rubén

    2017-11-01

    Sustainable agricultural practices have been developed as alternative to the use of agrochemicals, and viticulture is not exempt of that. Plant growth promoting rhizobacteria (PGPR) and smoke water extracts (SW) are environmentally-friendly alternative to those agrochemicals. The aim of this study was to investigate the single or combined effects of SW and the PGPR Pseudomonas fluorescens (Pf) and Bacillus licheniformis (Bl) on the physiology and biochemistry of grapevines plants. After 38 days, single applications of SW solutions and bacterial suspensions increase rooting and root length. Combined treatments had a slight positive effect compared to the water control. At the end of 60-days pot trial, grapevine treated with 1:1000 SW and Pf applied alone showed increases in stem length, leaf area and fresh weight of the roots, shoot and leaves, although not significantly differences from the water control were found. In addition, Pf augmented chlorophyll relative content, all treatments decreased the stomatal conductance (mainly 1:500 SW, Pf and 1:1000 SW + Bl), as well as lipid peroxidation in roots (mainly in bacterial treatments), and induced the synthesis of mono and sesquiterpenes in leaves, where the effect was enhanced in combined treatments. In conclusion, PGPR and SW are effective to improve growth of V. vinifera cuttings as well as to increase the plants defense mechanisms that may help them to cope with biotic and abiotic stresses. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. The inhibitory mechanism of Cordyceps sinensis on cigarette smoke extract-induced senescence in human bronchial epithelial cells

    Directory of Open Access Journals (Sweden)

    Liu AL

    2016-07-01

    Full Text Available Ailing Liu,1,2,* Jinxiang Wu,1,* Aijun Li,2 Wenxiang Bi,3 Tian Liu,1 Liuzhao Cao,1 Yahui Liu,1 Liang Dong1 1Department of Pulmonary Diseases, Qilu Hospital, Shandong University, Jinan, Shandong, People’s Republic of China; 2Department of Pulmonary Diseases, Weihai Municipal Hospital, Weihai, Shandong, People’s Republic of China; 3Institute of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, Shandong, People’s Republic of China *These authors contributed equally to this work Objectives: Cellular senescence is a state of irreversible growth arrest induced either by telomere shortening (replicative senescence or stress. The bronchial epithelial cell is often injured by inhaled toxic substances, such as cigarette smoke. In the present study, we investigated whether exposure to cigarette smoke extract (CSE induces senescence of bronchial epithelial cells; and Cordyceps sinensis mechanism of inhibition of CSE-induced cellular senescence.Methods: Human bronchial epithelial cells (16HBE cells cultured in vitro were treated with CSE and/or C. sinensis. p16, p21, and senescence-associated-galactosidase activity were used to detect cellular senescence with immunofluorescence, quantitative polymerase chain reaction, and Western blotting. Reactive oxygen species (ROS, PI3K/AKT/mTOR and their phosphorylated proteins were examined to testify the activation of signaling pathway by ROS fluorescent staining and Western blotting. Then, inhibitors of ROS and PI3K were used to further confirm the function of this pathway.Results: Cellular senescence was upregulated by CSE treatment, and C. sinensis can decrease CSE-induced cellular senescence. Activation of ROS/PI3K/AKT/mTOR signaling pathway was enhanced by CSE treatment, and decreased when C. sinensis was added. Blocking ROS/PI3K/AKT/mTOR signaling pathway can attenuate CSE-induced cellular senescence.Conclusion: CSE can induce cellular senescence in human bronchial

  20. Development of an in-orbit refocusing mechanism for the meteosat second generation weather satellites

    NARCIS (Netherlands)

    Verhoeff, P.; Mierlo, H.A. van; Braam, B.C.; Hopman, J.; Werkhoven, W.P. van; Kluse, M. le

    1998-01-01

    A Refocusing Mechanism (REM) has been designed and built for the SEVIRI instrument, the imager in the Meteosat Second Generation (MSG) satellite. The purpose of the mechanism is in-orbit focal adjustment of a mirror assembly which forms part of SEVIRI. As the MSG satellite observes the earth and its

  1. A Quantitative Comparison of some Mechanisms Generating Overpressure in Sedimentary Basins

    Energy Technology Data Exchange (ETDEWEB)

    Wangen, Magnus

    2001-05-01

    Expulsion of fluids in low permeable rock generate overpressure. Several mechanisms are suggested for fluid expulsion and overpressure build-up, and some of them have here been studied and compared. These are mechanical compaction, aquathermal pressuring, dehydration of clays, hydrocarbon generation and cementation of the pore space. A single pressure equation for these fluid expulsion processes has been studied. In particular, the source term in this pressure equation is studied carefully, because the source term consists of separate terms representing each mechanism for pressure build-up. The amount of fluid expelled from each mechanism is obtained from these individual contributions to the source term. It is shown that the rate of change of porosity can be expressed in at least two different ways for dehydration reactions and oil generation. One way in which the reduction in the solid volume enhances the porosity, and another where the porosity remains constant. A gravity number is defined by the permeability and the Darcy flux of the expelled fluid. The gravity number is shown to be a useful indicator for overpressure build-up. The gravity number is also used to estimate the thickness a seal needs for overpressure to rise from almost hydrostatic conditions above the seal to almost lithostatic conditions below the seal. Simple expressions for the Darcy fluxes caused by mechanical compaction, dehydration of clays, hydrocarbon generation and cementation of the pore space are derived. It is shown how these expressions can be combined with the gravity number to obtain an upper bound for the permeability for overpressure build-up to take place. Mechanical compaction and cementation of the pore space are shown to be the strongest expulsion mechanisms. Although most mechanisms can generate overpressure alone given a sufficiently low permeability, it is concluded that cementation of pore space is the most likely mechanism for overpressure generation in deeply buried

  2. Surface acoustic wave opto-mechanical oscillator and frequency comb generator.

    Science.gov (United States)

    Savchenkov, A A; Matsko, A B; Ilchenko, V S; Seidel, D; Maleki, L

    2011-09-01

    We report on realization of an efficient triply resonant coupling between two long lived optical modes and a high frequency surface acoustic wave (SAW) mode of the same monolithic crystalline whispering gallery mode resonator. The coupling results in an opto-mechanical oscillation and generation of a monochromatic SAW. A strong nonlinear interaction of this mechanical mode with other equidistant SAW modes leads to mechanical hyperparametric oscillation and generation of a SAW pulse train and associated frequency comb in the resonator. We visualized the comb by observing the modulation of the light escaping the resonator.

  3. Study of the relation between evaluation of strain distribution on superconducting coil and mechanical heat generation

    Science.gov (United States)

    Seino, Hiroshi; Kurihara, Minoru; Herai, Toshiki; Suzuki, Eiji

    2002-10-01

    In the superconducting Maglev system, on-board superconducting magnets (SCMs) are vibrated at various frequencies according to the train speed by the electromagnetic disturbance which is caused when the train passes over ground coils. Then a mechanical loss is generated inside the inner vessel in the SCM. This phenomenon increases the heat load on the cryogenic equipment in the SCM. It has been surmised that the mechanical heat inside the inner vessel is generated by the frictional heat caused by the relative microscopic slips between fasteners and superconducting coil (SC coil). Nevertheless, heat generation mechanisms inside the inner vessel have not been studied sufficiently. In this study, we suggest a hypothesis that the frictional heat generated by the relative microscopic slips between fasteners and a SC coil will be indicated if the calculated strain distribution on the SC coil is evaluated. The results of this study supported this hypothesis.

  4. Simulation Tool to Assess Mechanical and Electrical Stresses on Wind Turbine Generators: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Singh, M.; Muljadi, E.; Gevorgian, V.; Jonkman, J.

    2013-10-01

    Wind turbine generators (WTGs) consist of many different components to convert kinetic energy of the wind into electrical energy for end users. Wind energy is accessed to provide mechanical torque for driving the shaft of the electrical generator. The conversion from wind power to mechanical power is governed by the aerodynamic conversion. The aerodynamic-electrical-conversion efficiency of a WTGis influenced by the efficiency of the blades, the gearbox, the generator, and the power converter. This paper describes the use of MATLAB/Simulink to simulate the electrical and grid-related aspects of a WTG coupled with the FAST aero-elastic wind turbine computer-aided engineering tool to simulate the aerodynamic and mechanical aspects of a WTG. The combination of the two enables studiesinvolving both electrical and mechanical aspects of a WTG. This digest includes some examples of the capabilities of the FAST and MATLAB coupling, namely the effects of electrical faults on the blade moments.

  5. Comparison of Airway Pressure Release Ventilation to Conventional Mechanical Ventilation in the Early Management of Smoke Inhalation Injury in Swine

    Science.gov (United States)

    2011-01-01

    Measurements and Main Results: Anesthetized female Yorkshire pigs (n 33) inhaled room- temperature pine-bark smoke. Before injury, the pigs were...0188 Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing...Healthcare MR850JHU humidifier ( Auckland , NZ). Measurements. The following variables were measured: body weight, number of smoke breaths received, volume of

  6. Electricity Generation Characteristics of Energy-Harvesting System with Piezoelectric Element Using Mechanical-Acoustic Coupling

    Directory of Open Access Journals (Sweden)

    Hirotarou Tsuchiya

    2016-01-01

    Full Text Available This paper describes the electricity generation characteristics of a new energy-harvesting system with piezoelectric elements. The proposed system is composed of a rigid cylinder and thin plates at both ends. The piezoelectric elements are installed at the centers of both plates, and one side of each plate is subjected to a harmonic point force. In this system, vibration energy is converted into electrical energy via electromechanical coupling between the plate vibration and piezoelectric effect. In addition, the plate vibration excited by the point force induces a self-sustained vibration at the other plate via mechanical-acoustic coupling between the plate vibrations and an internal sound field into the cylindrical enclosure. Therefore, the electricity generation characteristics should be considered as an electromechanical-acoustic coupling problem. The characteristics are estimated theoretically and experimentally from the electric power in the electricity generation, the mechanical power supplied to the plate, and the electricity generation efficiency that is derived from the ratio of both power. In particular, the electricity generation efficiency is one of the most appropriate factors to evaluate a performance of electricity generation systems. Thus, the effect of mechanical-acoustic coupling is principally evaluated by examining the electricity generation efficiency.

  7. Smoke-induced seed germination in California chaparral

    Science.gov (United States)

    Keeley, J.E.; Fotheringham, C.J.

    1998-01-01

    The California chaparral community has a rich flora of species with different mechanisms for cuing germination to postfire conditions. Heat shock triggers germination of certain species but has no stimulatory effect on a great many other postfire species that are chemically stimulated by combustion products. Previous reports have shown that charred wood will induce germination, and here we report that smoke also induces germination in these same species. Smoke is highly effective, often inducing 100% germination in deeply dormant seed populations with 0% control germination. Smoke induces germination both directly and indirectly by aqueous or gaseous transfer from soil to seeds. Neither nitrate nor ammonium ions were effective in stimulating germination of smoke-stimulated species, nor were most of the quantitatively important gases generated by biomass smoke. Nitrogen dioxide, however, was very effective at inducing germination in Caulanthus heterophyllus (Brassicaceae), Emmenanthe penduliflora (Hydrophyllaceae), Phacelia grandiflora (Hydrophyllaceae), and Silene multinervia (Caryophyllaceae). Three species, Dendromecon rigida (Papaveraceae), Dicentra chrysantha, and Trichostema lanatum (Lamiaceae), failed to germinate unless smoke treatment was coupled with prior treatment of 1 yr soil storage. Smoke-stimulated germination was found in 25 chaparral species, representing 11 families, none of which were families known for heat-shock-stimulated germination. Seeds of smoke-stimulated species have many analogous characteristics that separate them from most heat-shock-stimulated seeds, including: (1) outer seed coats that are highly textured, (2) a poorly developed outer cuticle, (3) absence of a dense palisade tissue in the seed coat, and (4) a subdermal membrane that is semipermeable, allowing water passage but blocking entry of large (molecular mass > 500) solutes. Tentative evidence suggests that permeability characteristics of this subdermal layer are altered by

  8. Quitting Smoking

    Science.gov (United States)

    ... half of the people who don't quit smoking will die of smoking-related problems. Quitting smoking is important for your health. Soon after you ... they succeed. There are many ways to quit smoking. Some people stop "cold turkey." Others benefit from ...

  9. A novel holding mechanism for next generation active wireless capsule endoscopy.

    Science.gov (United States)

    Woods, Stephen P; Constandinou, Timothy G

    2015-08-01

    This paper proposes that next generation wireless capsule endoscopy (WCE) technology will feature active mechanical components (i.e. actuated) as opposed to current systems that are predominantly passive (e.g. for imaging purposes). Future systems will integrate microsystems that use micro-actuators to, for example, perform micro-surgery, take tissue samples, deliver medication, etc. In this paper we detail a novel, ultra-compact integrated mechanism for resisting peristalsis and describe how this can be fabricated in Nylon 6 using CNC milling. The holding action is achieved by extending an "anchor" spanning an effective 60.4mm circumference, for a 11.0mm diameter WCE. This function is achieved by a mechanism that occupies only 347.0mm(3) volume, including mechanics and actuator. This shows how exploiting conventional manufacturing processes can result in a radical change in the capabilities of WCE systems and empower the next generation of active devices.

  10. Simultaneous type and dimensional synthesis of articulated mechanisms for path-generation

    DEFF Research Database (Denmark)

    Kawamoto, Atsushi

    2004-01-01

    This paper deals with a path-generation problem for articulated mechanisms using a truss-based ground-structure representation. The proposed method uses both cross-sectional areas and nodal positions as design variables and thus leads to a simultaneous type and dimensional synthesis. For the anal......This paper deals with a path-generation problem for articulated mechanisms using a truss-based ground-structure representation. The proposed method uses both cross-sectional areas and nodal positions as design variables and thus leads to a simultaneous type and dimensional synthesis....... For the analysis part, it is essential to control the mechanism configurations so that the mechanism should stay within the same configuration space, thus stabilizing the optimization process and resulting in a realistic solution....

  11. Up-regulation of thromboxane A2 receptor expression by lipid soluble smoking particles through post-transcriptional mechanisms

    DEFF Research Database (Denmark)

    Zhang, Wei; Zhang, Yaping; Edvinsson, Lars

    2008-01-01

    Atherosclerosis is a key factor in vascular disease, and cigarette smoking is a well-known risk factor that may induce an inflammatory response and enhance plaque formation in arteries. Thromboxane (Tx) is one key inflammatory mediator involved in the pathogenesis of cardiovascular disease....... The present study was designed to test if lipid soluble smoking particles (DSP) enhance TxA(2) receptor (TP) expression in rat mesenteric arteries, and if intracellular mitogen-activated protein kinase (MAPK) pathways play a role. Organ culture of rat mesenteric arteries in the presence of DSP (0.2 microl...

  12. The electricity generation adequacy problem: Assessing dynamic effects of capacity remuneration mechanisms

    International Nuclear Information System (INIS)

    Hary, Nicolas; Rious, Vincent; Saguan, Marcelo

    2016-01-01

    Following liberalization reforms, the ability of power markets to provide satisfactory incentives for capacity investments has become a major concern. In particular, current energy markets can exhibit a phenomenon of investment cycles, which generate phases of under and over-capacity, and hence additional costs and risks for generation adequacy. To cope with these issues, new mechanisms, called capacity remuneration mechanisms (CRM), have been (or will be) implemented. This paper assesses the dynamic effects of two CRMs, the capacity market and the strategic reserve mechanism, and studies to what extent they can reduce the investment cycles. Generation costs and shortage costs of both mechanisms are also compared to conclude on their effectivity and economic efficiency. A simulation model, based on system dynamics, is developed to study the functioning of both CRMs and the related investment decisions. The results highlight the benefits of deploying CRMs to solve the adequacy issue: shortages are strongly reduced compared to an energy-only market. Besides, the capacity market appears to be more beneficial, since it experiences fewer shortages and generation costs are lower. These comparisons can be used by policy makers (in particular in Europe, where these two CRMs are mainly debated) to determine which CRM to adopt. - Highlights: •A study of the dynamic effects of CRMs on generation investments is provided. •Capacity market and strategic reserve mechanism are compared. •Both CRMs reduce the cyclical tendencies prone to appear in energy-only market. •The capacity market experiences fewer shortages and generation costs are lower.

  13. Up-regulation of thromboxane A2 receptor expression by lipid soluble smoking particles through post-transcriptional mechanisms

    DEFF Research Database (Denmark)

    Zhang, Wei; Zhang, Yaping; Edvinsson, Lars

    2008-01-01

    . The present study was designed to test if lipid soluble smoking particles (DSP) enhance TxA(2) receptor (TP) expression in rat mesenteric arteries, and if intracellular mitogen-activated protein kinase (MAPK) pathways play a role. Organ culture of rat mesenteric arteries in the presence of DSP (0.2 microl...

  14. Impact of Conflict Management Strategies on the Generation Mechanism of Miners' Unsafe Behavior Tendency

    Science.gov (United States)

    Li, Ji-Zu; Zhang, Ya-Ping; Liu, Xiao-Guang; Liu, Yao-Long; Wang, Tian-Ri

    2017-01-01

    In this paper, we examine the relationship between the generation mechanism of miners' unsafe behavior tendency and conflict management strategies, including cooperative conflict management strategy, competitive conflict management strategy and avoidant conflict management strategy. Miners from 3 collieries in Shanxi province completed a…

  15. Hierarchy of mechanisms involved in generating Na/K-ATPase polarity in MDCK epithelial cells

    NARCIS (Netherlands)

    Mays, R.W.; Siemers, K.A.; Fritz, B.A.; Lowe, A.W.; van Meer, G.; Nelson, W.J.

    1995-01-01

    We have studied mechanisms involved in generating a polarized distribution of Na/K-ATPase in the basal-lateral membrane of two clones of MDCK II cells. Both clones exhibit polarized distributions of marker proteins of the apical and basal-lateral membranes, including Na/K-ATPase, at steady state.

  16. CURVES AND AESTHETIC SURFACES GENERATED BY THE R-R-RTR MECHANISM

    Directory of Open Access Journals (Sweden)

    Liliana LUCA

    2013-05-01

    Full Text Available Let’s consider a mechanism having two driving elements with revolving movements and a RTR dyad, with elements of null length and aesthetic tracks of a point are determined on a rod, for various linear movement laws of driving elements. The generated curves revolve around x and y axes and aesthetic surfaces result.

  17. Design mechanic generator under speed bumper to support electricity recourse for urban traffic light

    Science.gov (United States)

    Sabri, M.; Lauzuardy, Jason; Syam, Bustami

    2018-03-01

    The electrical energy needs for the traffic lights in some cities of developing countries cannot be achieved continuously due to limited capacity and interruption of electricity distribution, the main power plant. This issues can lead to congestion at the crossroads. To overcome the problem of street chaos due to power failure, we can cultivate to provide electrical energy from other sources such as using the bumper to generate kinetic energy, which can be converted into electrical energy. This study designed a generator mechanic that will be mounted on the bumper construction to generate electricity for the purposes of traffic lights at the crossroads. The Mechanical generator is composed of springs, levers, sprockets, chains, flywheel and customize power generator. Through the rotation of the flywheel, we can earned 9 Volt DC voltage and electrical current of 5.89 Ampere. This achievement can be used to charge the accumulator which can be used to power the traffic lights, and to charge the accumulator capacity of 6 Ah, the generator works in the charging time for 1.01 hours.

  18. Understanding the impact of school tobacco policies on adolescent smoking behaviour: A realist review.

    Science.gov (United States)

    Schreuders, Michael; Nuyts, Paulien A W; van den Putte, Bas; Kunst, Anton E

    2017-06-01

    Secondary schools increasingly implement school tobacco policies (STPs) to decrease adolescents' smoking. Recent studies suggested that STPs' impact depends on their implementation. We examined adolescents' cognitive and behavioural responses to STPs that impact adolescents' smoking and how these responses depend on elements of STPs' implementation. To examine STPs and adolescent smoking, we performed a realist review, which is an explanatory approach that synthesizes existing evidence into a program theory that links elements of STPs' implementation to outcomes by specifying its underlying generative mechanisms. The search was performed in MEDLINE/PubMed, PsycINFO, and Embase between January 1991 and 2016. Thirty-seven English language articles were identified for inclusion, reporting quantitative and/or qualitative primary evidence on STPs at secondary schools, adolescent smoking behaviour, and mechanisms. From these articles, evidence was extracted about mechanisms that decrease smoking and associated countervailing-mechanisms that reduce, nullify, or revert this positive impact. The program theory showed that STPs may trigger four mechanisms and seven associated countervailing-mechanisms. Adolescents' smoking decreases if STPs make them feel they can get sanctioned, feel less pressure to conform to smokers, internalise anti-smoking beliefs, and find it easier to stick to the decision not to smoke. This positive impact may reduce, nullify, or revert if the implementation of STPs cause adolescents to find alternative places to smoke, develop new social meanings of smoking, want to belong in smoker groups, internalise beliefs that smoking is not bad or that it asserts personal autonomy, or alienate from schools and schools' messages. The program theory, moreover, provided insights on how elements of STPs' implementation trigger mechanisms and avoid the countervailing-mechanisms. STPs' impact can be influenced by adequate implementation and embedding them in

  19. Novel mechanism of network protection against the new generation of cyber attacks

    Science.gov (United States)

    Milovanov, Alexander; Bukshpun, Leonid; Pradhan, Ranjit

    2012-06-01

    A new intelligent mechanism is presented to protect networks against the new generation of cyber attacks. This mechanism integrates TCP/UDP/IP protocol stack protection and attacker/intruder deception to eliminate existing TCP/UDP/IP protocol stack vulnerabilities. It allows to detect currently undetectable, highly distributed, low-frequency attacks such as distributed denial-of-service (DDoS) attacks, coordinated attacks, botnet, and stealth network reconnaissance. The mechanism also allows insulating attacker/intruder from the network and redirecting the attack to a simulated network acting as a decoy. As a result, network security personnel gain sufficient time to defend the network and collect the attack information. The presented approach can be incorporated into wireless or wired networks that require protection against known and the new generation of cyber attacks.

  20. Guideline Implementation: Surgical Smoke Safety.

    Science.gov (United States)

    Fencl, Jennifer L

    2017-05-01

    Research conducted during the past four decades has demonstrated that surgical smoke generated from the use of energy-generating devices in surgery contains toxic and biohazardous substances that present risks to perioperative team members and patients. Despite the increase in information available, however, perioperative personnel continue to demonstrate a lack of knowledge of these hazards and lack of compliance with recommendations for evacuating smoke during surgical procedures. The new AORN "Guideline for surgical smoke safety" provides guidance on surgical smoke management. This article focuses on key points of the guideline to help perioperative personnel promote smoke-free work environments; evacuate surgical smoke; and develop education programs and competency verification tools, policies and procedures, and quality improvement initiatives related to controlling surgical smoke. Perioperative RNs should review the complete guideline for additional information and for guidance when writing and updating policies and procedures. Copyright © 2017 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  1. Dynamical mechanism of symmetry breaking and particle mass generation in gauge field theories

    International Nuclear Information System (INIS)

    Miranskij, V.A.; Fomin, P.I.

    1985-01-01

    The dynamics of the spotaneous symmetry breaking and the particle mass generation in gauge theories with no fundamental scalar fields is considered. The emphasis is on the consideration of the symmetry breaking mechanism connected with the dynamics of the supercritical Coulomb-like forces caused by the gauge boson exchange between fermions. This mechanism is applied to different gauge theories, in particular, to the description of the spontaneous chira symmetry breaking in quantum chromodynamics. The mass relations for pseudoscalar meson nonet are obtained and it is shown that this mechanism resuls in the dynamical realisation of the hypothesis of the partial conservation of the axial-vector currents. The qualitative description of scalar mesons is given. The nature of the ultraviolet divergencies in quantum electrodynamics (QED) is investigated from the viewpoint of the dynamics of the fermion mass generation. The mechanism of the appearance of the additional (in comparison with perturbation theory) ultraviolet divergencies in QED with large bare coupling constant is indicated. The physical phenomenon underlying this mechanism is identified as the field theory analogue of the quantum mechanical ''fall into the centre'' (collapse) phenomenon. The similr phenomenon is shown to take place in some two-dimensional quantum field models. The dynamics of the bifermion condensates formation in tumblin gauge theories is briefly discussed

  2. Medicinal smokes.

    Science.gov (United States)

    Mohagheghzadeh, Abdolali; Faridi, Pouya; Shams-Ardakani, Mohammadreza; Ghasemi, Younes

    2006-11-24

    All through time, humans have used smoke of medicinal plants to cure illness. To the best of our knowledge, the ethnopharmacological aspects of natural products' smoke for therapy and health care have not been studied. Mono- and multi-ingredient herbal and non-herbal remedies administered as smoke from 50 countries across the 5 continents are reviewed. Most of the 265 plant species of mono-ingredient remedies studied belong to Asteraceae (10.6%), followed by Solanaceae (10.2%), Fabaceae (9.8%) and Apiaceae (5.3%). The most frequent medical indications for medicinal smoke are pulmonary (23.5%), neurological (21.8%) and dermatological (8.1%). Other uses of smoke are not exactly medical but beneficial to health, and include smoke as a preservative or a repellent and the social use of smoke. The three main methods for administering smoke are inhalation, which accounts for 71.5% of the indications; smoke directed at a specific organ or body part, which accounts for 24.5%; ambient smoke (passive smoking), which makes up the remaining 4.0%. Whereas inhalation is typically used in the treatment of pulmonary and neurological disorders and directed smoke in localized situations, such as dermatological and genito-urinary disorders, ambient smoke is not directed at the body at all but used as an air purifier. The advantages of smoke-based remedies are rapid delivery to the brain, more efficient absorption by the body and lower costs of production. This review highlights the fact that not enough is known about medicinal smoke and that a lot of natural products have potential for use as medicine in the smoke form. Furthermore, this review argues in favor of medicinal smoke extended use in modern medicine as a form of drug delivery and as a promising source of new active natural ingredients.

  3. Smoking, Stress, and Coronary Heart Disease.

    Science.gov (United States)

    Epstein, Leonard H.; Perkins, Kenneth A.

    1988-01-01

    Focuses on the interrelation between stressors and smoking, and on its potential impact on coronary heart disease risk beyond that due to stressors or to smoking alone. Reviews evidence supporting the stress-smoking interrelationship, its relevance to the risk of heart disease, and mechanisms explaining why smokers smoke more during stress and why…

  4. Smoking Cessation

    Science.gov (United States)

    ... Division of Reproductive Health More CDC Sites Quitting Smoking Recommend on Facebook Tweet Share Compartir On This ... You are never too old to quit . Stopping smoking is associated with the following health benefits: 1, ...

  5. Diversity Generator Mechanisms Are Essential Components of Biological Systems: The Two Queen Hypothesis

    Directory of Open Access Journals (Sweden)

    Eric Muraille

    2018-02-01

    Full Text Available Diversity is widely known to fuel adaptation and evolutionary processes and increase robustness at the population, species and ecosystem levels. The Neo-Darwinian paradigm proposes that the diversity of biological entities is the consequence of genetic changes arising spontaneously and randomly, without regard for their usefulness. However, a growing body of evidence demonstrates that the evolutionary process has shaped mechanisms, such as horizontal gene transfer mechanisms, meiosis and the adaptive immune system, which has resulted in the regulated generation of diversity among populations. Though their origins are unrelated, these diversity generator (DG mechanisms share common functional properties. They (i contribute to the great unpredictability of the composition and/or behavior of biological systems, (ii favor robustness and collectivism among populations and (iii operate mainly by manipulating the systems that control the interaction of living beings with their environment. The definition proposed here for DGs is based on these properties and can be used to identify them according to function. Interestingly, prokaryotic DGs appear to be mainly reactive, as they generate diversity in response to environmental stress. They are involved in the widely described Red Queen/arms race/Cairnsian dynamic. The emergence of multicellular organisms harboring K selection traits (longer reproductive life cycle and smaller population size has led to the acquisition of a new class of DGs that act anticipatively to stress pressures and generate a distinct dynamic called the “White Queen” here. The existence of DGs leads to the view of evolution as a more “intelligent” and Lamarckian-like process. Their repeated selection during evolution could be a neglected example of convergent evolution and suggests that some parts of the evolutionary process are tightly constrained by ecological factors, such as the population size, the generation time and

  6. Diversity Generator Mechanisms Are Essential Components of Biological Systems: The Two Queen Hypothesis.

    Science.gov (United States)

    Muraille, Eric

    2018-01-01

    Diversity is widely known to fuel adaptation and evolutionary processes and increase robustness at the population, species and ecosystem levels. The Neo-Darwinian paradigm proposes that the diversity of biological entities is the consequence of genetic changes arising spontaneously and randomly, without regard for their usefulness. However, a growing body of evidence demonstrates that the evolutionary process has shaped mechanisms, such as horizontal gene transfer mechanisms, meiosis and the adaptive immune system, which has resulted in the regulated generation of diversity among populations. Though their origins are unrelated, these diversity generator (DG) mechanisms share common functional properties. They (i) contribute to the great unpredictability of the composition and/or behavior of biological systems, (ii) favor robustness and collectivism among populations and (iii) operate mainly by manipulating the systems that control the interaction of living beings with their environment. The definition proposed here for DGs is based on these properties and can be used to identify them according to function. Interestingly, prokaryotic DGs appear to be mainly reactive, as they generate diversity in response to environmental stress. They are involved in the widely described Red Queen/arms race/Cairnsian dynamic. The emergence of multicellular organisms harboring K selection traits (longer reproductive life cycle and smaller population size) has led to the acquisition of a new class of DGs that act anticipatively to stress pressures and generate a distinct dynamic called the "White Queen" here. The existence of DGs leads to the view of evolution as a more "intelligent" and Lamarckian-like process. Their repeated selection during evolution could be a neglected example of convergent evolution and suggests that some parts of the evolutionary process are tightly constrained by ecological factors, such as the population size, the generation time and the intensity of

  7. Beyond pure offsetting: Assessing options to generate Net-Mitigation-Effects in carbon market mechanisms

    International Nuclear Information System (INIS)

    Warnecke, Carsten; Wartmann, Sina; Höhne, Niklas; Blok, Kornelis

    2014-01-01

    The current project-based carbon market mechanisms such as the Clean Development Mechanism (CDM) and the Joint Implementation (JI) do not have a direct impact on global greenhouse gas emission levels, because they only replace or offset emissions. Nor do they contribute to host country's national greenhouse gas emission reduction targets. Contributions to net emission reductions in host countries is likely to become mandatory in new mechanisms under development such as in the framework for various approaches, a new market-based mechanism and even in a reformed JI. This research analysed the question if approaches for carbon market-based mechanisms exist that allow the generation of net emission reductions in host countries while keeping project initiation attractive. We present a criteria-based assessment method and apply it for four generic options in existing mechanisms and derive implications for future mechanism frameworks. We identified the application of “discounts” on the amount of avoided emissions for the issuance of carbon credits and “standardisation below business as usual” as most promising options over “limiting the crediting period” and “over-conservativeness”. We propose to apply these options differentiated over project types based on internal rate of return to ensure cost-efficiency and attractiveness. - Highlights: • Options for net emission reductions of market-based mechanisms are assessed. • Research combines past and current views for project and sector-based mechanisms. • Implementation ensures initiation of mitigation activities is not discouraged. • Important insights for methodological design of new market-based mechanisms. • Profitability-based approach for project-based mechanisms suggested

  8. Dynamic model of Stirling engine crank mechanism with connected electric generator

    OpenAIRE

    Vlach R.; Sikora M.

    2009-01-01

    This paper treats of a numerical dynamic model of Stirling engine crank mechanism. The model is included in the complex model of combined heat and power unit. The unit is composed of the Stirling engine and of attached three-phase synchronous generator. This generator should start the Stirling engine in motor mode as well. It is necessary to combine the crank shaft dynamic model and the complete thermal model of Stirling engine for simulations and analyses of engine run. Our aim is to create ...

  9. Teen Smoking

    Science.gov (United States)

    ... al. Parental smoking, closeness to parents, and youth smoking. American Journal of Health Behavior. 2007;31:261. Guide to ... cigarette use with initiation of combustible tobacco product smoking in early adolescence. Journal of the American Medical Association. 2015;314:700. ...

  10. Second Generation MOSAIC:A Novel Mechanism Based on Reference Database for Map Updating

    Science.gov (United States)

    Hu, G.; Bignone, F.

    2011-08-01

    A totally new automatic workflow mechanism, named Second generation Mosaic module, based on the well-known Pixel Factory system, will be introduced here, which enables existing digital orthoimages and mosaics to be quickly updated. The process extracts all required parameters from the reference database to be able to perform automatic bundle adjustment and radiometric adaptation.In this paper, two examples for both satellite data and aerial data processed based on this mechanism will be presented here and discussed. Finally, the cost reduction will also be analysed according to the real mapping updating project.In a final statement, this paper will present an integrated solution named second generation mosaic module based on the well-known Pixel Factory system which is completely dedicated to fast processing of photogrammetric products Thanks to this integrated hardware and software solution, it is even possible to manage large data volume quickly in order to have precise map updating information as soon as possible after acquisition.

  11. A discrete mechanics approach to gait generation for the compass-type biped robot

    Science.gov (United States)

    Kai, Tatsuya; Shintani, Takeshi

    In this paper, we develop a new approach based on discrete mechanics to a gait generation problem for the compass-type biped robot. First, both continuous-time and discrete-time models of the compass-type biped robot are derived. We next formulate a discrete gait generation problem for the discrete compass-type biped robot as a finite dimensional nonlinear optimal control problem and show an algorithm to solve the problem based on the sequential quadratic programming. Then, we propose a transformation method that converts a discrete-time control input into a continuous-time zero-order hold one and apply it to gait generation for the continuous compass-type biped robot. Some simulations are also shown in order to verify the effectiveness of our new approach.

  12. Generalized generating functional for mixed-representation Green's functions: A quantum-mechanical approach

    Science.gov (United States)

    Blasone, Massimo; Jizba, Petr; Smaldone, Luca

    2017-11-01

    When one tries to take into account the nontrivial vacuum structure of quantum field theory, the standard functional-integral tools, such as generating functionals or transitional amplitudes, are often quite inadequate for such purposes. Here we propose a generalized generating functional for Green's functions which allows one to easily distinguish among a continuous set of vacua that are mutually connected via unitary canonical transformations. In order to keep our discussion as simple as possible, we limit ourselves to quantum mechanics where the generating functional of Green's functions is constructed by means of phase-space path integrals. The quantum-mechanical setting allows us to accentuate the main logical steps involved without embarking on technical complications such as renormalization or inequivalent representations that should otherwise be addressed in the full-fledged quantum field theory. We illustrate the inner workings of the generating functional obtained by discussing Green's functions among vacua that are mutually connected via translations and dilatations. Salient issues, including connection with quantum field theory, vacuum-to-vacuum transition amplitudes, and perturbation expansion in the vacuum parameter, are also briefly discussed.

  13. Various bio-mechanical factors affecting heat generation during osteotomy preparation: A systematic review.

    Science.gov (United States)

    Chauhan, Chirag J; Shah, Darshana N; Sutaria, Foram B

    2018-01-01

    As implant site preparation and bone are critical precursors to primary healing, thermal and mechanical damage to the bone must be minimized during the preparation of the implant site. Moreover, excessively traumatic surgery can adversely affect the maturation of bone tissue at the bone/implant interface and consequently diminish the predictability of osseointegration. So, this study was carried out to evaluate the various biological and mechanical factors responsible for heat generation during osteotomy site preparation to reduce the same for successful osseointegration of dental implants. A broad search of the dental literature in PubMed added by manual search was performed for articles published between 1992 and December 2015. Various bio-mechanical factors related to dental implant osteotomy preparation such as dental implant drill designs/material/wear, drilling methods, type of irrigation, and bone quality were reviewed. Titles and abstracts were screened and articles which fulfilled the inclusion criteria were selected for a full-text reading. The initial database search yielded 123 titles, of which 59 titles were discarded after reading the titles and abstracts, 30 articles were again excluded based on inclusion and exclusion criteria, and finally 34 articles were selected for data extraction. Many biological and mechanical factors responsible for heat generation were found. Literatures of this review study have indicated that there are various bio-mechanical reasons, which affect the temperature rise during osteotomy and suggest that the amount of heat generation is a multifactorial in nature and it should be minimized for better primary healing of the implant site.

  14. Various bio-mechanical factors affecting heat generation during osteotomy preparation: A systematic review

    Directory of Open Access Journals (Sweden)

    Chirag J Chauhan

    2018-01-01

    Full Text Available Background: As implant site preparation and bone are critical precursors to primary healing, thermal and mechanical damage to the bone must be minimized during the preparation of the implant site. Moreover, excessively traumatic surgery can adversely affect the maturation of bone tissue at the bone/implant interface and consequently diminish the predictability of osseointegration. So, this study was carried out to evaluate the various biological and mechanical factors responsible for heat generation during osteotomy site preparation to reduce the same for successful osseointegration of dental implants. Study Design: A broad search of the dental literature in PubMed added by manual search was performed for articles published between 1992 and December 2015. Various bio-mechanical factors related to dental implant osteotomy preparation such as dental implant drill designs/material/wear, drilling methods, type of irrigation, and bone quality were reviewed. Titles and abstracts were screened and articles which fulfilled the inclusion criteria were selected for a full-text reading. Results: The initial database search yielded 123 titles, of which 59 titles were discarded after reading the titles and abstracts, 30 articles were again excluded based on inclusion and exclusion criteria, and finally 34 articles were selected for data extraction. Many biological and mechanical factors responsible for heat generation were found. Conclusion: Literatures of this review study have indicated that there are various bio-mechanical reasons, which affect the temperature rise during osteotomy and suggest that the amount of heat generation is a multifactorial in nature and it should be minimized for better primary healing of the implant site.

  15. Affirming independence: Exploring mechanisms underlying a values affirmation intervention for first-generation students.

    Science.gov (United States)

    Tibbetts, Yoi; Harackiewicz, Judith M; Canning, Elizabeth A; Boston, Jilana S; Priniski, Stacy J; Hyde, Janet S

    2016-05-01

    First-generation college students (students for whom neither parent has a 4-year college degree) earn lower grades and worry more about whether they belong in college, compared with continuing-generation students (who have at least 1 parent with a 4-year college degree). We conducted a longitudinal follow-up of participants from a study in which a values-affirmation intervention improved performance in a biology course for first-generation college students, and found that the treatment effect on grades persisted 3 years later. First-generation students in the treatment condition obtained a GPA that was, on average, .18 points higher than first-generation students in the control condition, 3 years after values affirmation was implemented (Study 1A). We explored mechanisms by testing whether the values-affirmation effects were predicated on first-generation students reflecting on interdependent values (thus affirming their values that are consistent with working-class culture) or independent values (thus affirming their values that are consistent with the culture of higher education). We found that when first-generation students wrote about their independence, they obtained higher grades (both in the semester in which values affirmation was implemented and in subsequent semesters) and felt less concerned about their background. In a separate laboratory experiment (Study 2) we manipulated the extent to which participants wrote about independence and found that encouraging first-generation students to write more about their independence improved their performance on a math test. These studies highlight the potential of having FG students focus on their own independence. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  16. Reaction mechanism and influence factors analysis for calcium sulfide generation in the process of phosphogypsum decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Liping, E-mail: lpma2522@hotmail.com [Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Niu, Xuekui; Hou, Juan; Zheng, Shaocong; Xu, Wenjuan [Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650093 (China)

    2011-11-10

    Highlights: Black-Right-Pointing-Pointer Reusing phosphogypsum is to decompose and recycle Ca and sulfur. Black-Right-Pointing-Pointer FactSage6.1 software was used to simulate the decomposition reactions. Black-Right-Pointing-Pointer Experiments had been taken with high sulfur concentration coal as reducing agent. Black-Right-Pointing-Pointer The reaction mechanism of CaS generation had been analysis, 1100 Degree-Sign C could be the best temperature for PG decomposition. - Abstract: FactSage6.1 software simulation and experiments had been used to analysis the reaction mechanism and influence factors for CaS generation during the process of phosphogypsum decomposition. Thermodynamic calculation showed that the reaction for CaS generation was very complex and CaS was generated mainly through solid-solid reaction and gas-solid reaction. The proper CO and CO{sub 2} have benefit for improving the decomposition effects of phosphogypsum and reducing the generation of CaS at 1100 Degree-Sign C. Using high sulfur concentration coal as reducer, the proper reaction conditions to control the generation of CaS were: the coal particle size was between 60 mesh and 100 mesh, reaction temperature was above 1100 Degree-Sign C and the heating rate was 5 Degree-Sign C/min. Experimental and theoretical calculation indicated that the concentration of CaS was only ten percents in the solid product at 1100 Degree-Sign C, which is favorable for the further cement producing using solid production.

  17. Ab initio Algorithmic Causal Deconvolution of Intertwined Programs and Networks by Generative Mechanism

    KAUST Repository

    Zenil, Hector

    2018-02-18

    To extract and learn representations leading to generative mechanisms from data, especially without making arbitrary decisions and biased assumptions, is a central challenge in most areas of scientific research particularly in connection to current major limitations of influential topics and methods of machine and deep learning as they have often lost sight of the model component. Complex data is usually produced by interacting sources with different mechanisms. Here we introduce a parameter-free model-based approach, based upon the seminal concept of Algorithmic Probability, that decomposes an observation and signal into its most likely algorithmic generative mechanisms. Our methods use a causal calculus to infer model representations. We demonstrate the method ability to distinguish interacting mechanisms and deconvolve them, regardless of whether the objects produce strings, space-time evolution diagrams, images or networks. We numerically test and evaluate our method and find that it can disentangle observations from discrete dynamic systems, random and complex networks. We think that these causal inference techniques can contribute as key pieces of information for estimations of probability distributions complementing other more statistical-oriented techniques that otherwise lack model inference capabilities.

  18. HIV & smoking in India.

    Science.gov (United States)

    Kumar, S Ramesh; Swaminathan, Soumya; Flanigan, Timothy; Mayer, K H; Niaura, Raymond

    2009-07-01

    There are approximately 2.5 million people living with HIV/AIDS (PLWHA) in India - the young being particularly vulnerable. The prevalence of smoking has increased in India especially among rural, lower socio-economic and illiterate men. Studies have shown that HIV-infected smokers may be at additional risk for several infectious and non-infectious complications, including malignancies and cardiovascular events. Smoking alters immunological mechanisms and suppresses host defenses in the alveolar environment. HIV-infected smokers have also been found to have a poorer response to antiretroviral therapy and a higher risk of death. HIV-infected individuals who smoke could be at a greater risk for developing TB and subsequently suffer higher morbidity and mortality than those who do not smoke. Currently available smoking cessation interventions like physician's advice, nicotine replacement therapy and pharmacological agents like bupropion and varenicline have had varying degrees of success. Smoking cessation intervention in the HIV-infected population might be more complex because of associated psychosocial problems like drug addiction, alcoholism, depression, etc. More research including clinical trials testing the efficacy of smoking cessation interventions in HIV infected persons is required in India. In addition to public health measures like banning smoking in public places and raising tobacco tax, comprehensive guidelines for health workers can help address this problem. Counselling on smoking cessation should be one of the main components of primary care, especially in the management of HIV-infected persons. This review highlights the importance of smoking cessation among HIV-infected persons in India.

  19. Effect of vortex generators on the closing transient flow of bileaflet mechanical heart valves

    Science.gov (United States)

    Murphy, David; Dasi, Lakshmi; Yoganathan, Ajit; Glezer, Ari

    2006-11-01

    The time-periodic closing of bileaflet mechanical heart valves is accompanied by a strong flow transient that is associated with the formation of a counter-rotating vortex pair near the b-datum line of leaflet edges. The strong transitory shear that is generated by these vortices may be damaging to blood elements and may result in platelet activation. In the present work, these flow transients are mitigated using miniature vortex generator arrays that are embedded on the surface of the leaflets. Two vortex generator designs were investigated: one design comprised staggered rectangular fins and the other one staggered hemispheres. The closing transients in the absence and presence of the passive vortex generators are characterized using phase locked PIV measurements. The study utilizes a 25 mm St. Jude Medical valve placed in the aortic position of the Georgia Tech left heart simulator. Measurements of the velocity field in the center plane of the leaflets demonstrate that the dynamics of the transient vortices that precede the formation of the leakage jets can be significantly altered and controlled by relatively simple passive modifications of existing valve designs. Human blood experiments validated the effectiveness of miniature vortex generators in reducing thrombus formation by over 42 percent.

  20. Methylation on RNA: A Potential Mechanism Related to Immune Priming within But Not across Generations.

    Science.gov (United States)

    Castro-Vargas, Cynthia; Linares-López, César; López-Torres, Adolfo; Wrobel, Katarzyna; Torres-Guzmán, Juan C; Hernández, Gloria A G; Wrobel, Kazimierz; Lanz-Mendoza, Humberto; Contreras-Garduño, Jorge

    2017-01-01

    Invertebrate immune priming is a growing field in immunology. This phenomenon refers to the ability of invertebrates to generate a more vigorous immune response to a second encounter with a specific pathogen and can occur within and across generations. Although the precise mechanism has not been elucidated, it has been suggested that methylation of DNA is a cornerstone for this phenomenon. Here, using a novel method of analytical chemistry (a reversed-phase liquid chromatography procedure) and the beetle Tenebrio molitor as a model system, we did not find evidence to support this hypothesis taking into account the percentage of methylated cytosine entities in DNA (5mdC) within or across generations. However, we found a lower percentage of methylated cytosine entities in RNA (5mC) within but not across generations in immune priming experiments with adults against the bacteria Micrococcus lysodeikticus and larvae against the fungus Metarhizium anisopliae . To our knowledge, this is the first report suggesting a role of differential methylation on RNA during immune priming within generations.

  1. Maximum Smoke Temperature in Non-Smoke Model Evacuation Region for Semi-Transverse Tunnel Fire

    OpenAIRE

    B. Lou; Y. Qiu; X. Long

    2017-01-01

    Smoke temperature distribution in non-smoke evacuation under different mechanical smoke exhaust rates of semi-transverse tunnel fire were studied by FDS numerical simulation in this paper. The effect of fire heat release rate (10MW 20MW and 30MW) and exhaust rate (from 0 to 160m3/s) on the maximum smoke temperature in non-smoke evacuation region was discussed. Results show that the maximum smoke temperature in non-smoke evacuation region decreased with smoke exhaust rate. Plug-holing was obse...

  2. Cigarette Smoking and Dyspnea Perception

    Directory of Open Access Journals (Sweden)

    Scano Giorgio

    2004-03-01

    Full Text Available Abstract Cigarette smoking has been implicated as an important risk factor for the development of respiratory symptoms in adults. The relationship of dyspnea with cigarette smoking has been examined in smokers and ex-smokers and the beneficial effects of smoking cessation have been demonstrated. Recent studies reported that in subjects who smoke cigarettes the risk of developing respiratory symptoms is higher in a dose-dependent way. Environmental tobacco smoke heavily influences the incidence of respiratory symptoms in both adults and in children. Up to the present time, the mechanisms whereby cigarette smoking causes dyspnea perception remain to be defined. Abnormalities in sensory nerves might diminish the perception of bronchoconstriction in smokers. In this regard, it has been postulated that prolonged exposure to cigarette smoke may lead to chronic depletion of sensory nerve neurotransmitters. Eosinophil airway inflammation has been proposed as a determinant of breathlessness via mechanisms affecting either the mechanical pathways that control breathlessness or the afferent nerves involved in perception of dyspnea. An increased number of eosinophils in some smokers implies the possibility that smoking may trigger immunological or other reactions associated with eosinophilia. In conclusion, cigarette smoking is by far one of the greatest risk factors for most respiratory symptoms, including dyspnea. Smoking is associated with the development of symptoms in a dose-dependent way and eosinophilia and airway hyperresponsiveness (AHR increase the risk of developing dyspnea.

  3. Enhanced Efficiency of Thermoelectric Generator by Optimizing Mechanical and Electrical Structures

    Directory of Open Access Journals (Sweden)

    Jinlong Chen

    2017-09-01

    Full Text Available Much attention has been paid to the application of low temperature thermal resources, especially for power generation in recent years. Most of the current commercialized thermal (including geothermal power-generation technologies convert thermal energy to electric energy indirectly, that is, making mechanical work before producing electricity. Technology using a thermoelectric generator (TEG, however, can directly transform thermal energy into electricity through the Seebeck effect. TEG technology has many advantages such as compactness, quietness, and reliability because there are no moving parts. One of the biggest disadvantages of TEGs is the low efficiency from thermal to electric energy. For this reason, we redesigned and modified our previous 1 KW (at a temperature difference of around 120 °C TEG system. The output power of the system was improved significantly, about 34.6% greater; the instantaneous efficiency of the TEG system could reach about 6.5%. Laboratory experiments have been conducted to measure the output power at different conditions: different connection modes between TEG modules, different mechanical structures, and different temperature differences between hot and cold sides. The TEG apparatus has been tested and the data have been presented. This kind of TEG power system can be applied in many thermal and geothermal sites with low temperature resources, including oil fields where fossil and geothermal energies are coproduced.

  4. Real-time transient stabilization and voltage regulation of power generators with unknown mechanical power input

    International Nuclear Information System (INIS)

    Kenne, Godpromesse; Goma, Raphael; Nkwawo, Homere; Lamnabhi-Lagarrigue, Francoise; Arzande, Amir; Vannier, Jean Claude

    2010-01-01

    A nonlinear adaptive excitation controller is proposed to enhance the transient stability and voltage regulation of synchronous generators with unknown power angle and mechanical power input. The proposed method is based on a standard third-order model of a synchronous generator which requires only information about the physical available measurements of relative angular speed, active electric power, infinite bus and generator terminal voltages. The operating conditions are computed online using the above physical available measurements, the terminal voltage reference value and the estimate of the mechanical power input. The proposed design is therefore capable of providing satisfactory voltage in the presence of unknown variations of the power system operating conditions. Using the concept of sliding mode equivalent control techniques, a robust decentralized adaptive controller which insures the exponential convergence of the outputs to the desired ones, is obtained. Real-time experimental results are reported, comparing the performance of the proposed adaptive nonlinear control scheme to one of the conventional AVR/PSS controller. The high simplicity of the overall adaptive control scheme and its robustness with respect to line impedance variation including critical unbalanced operating condition and temporary turbine fault, constitute the main positive features of the proposed approach.

  5. Fracture Mechanics Method for Word Embedding Generation of Neural Probabilistic Linguistic Model

    Directory of Open Access Journals (Sweden)

    Size Bi

    2016-01-01

    Full Text Available Word embedding, a lexical vector representation generated via the neural linguistic model (NLM, is empirically demonstrated to be appropriate for improvement of the performance of traditional language model. However, the supreme dimensionality that is inherent in NLM contributes to the problems of hyperparameters and long-time training in modeling. Here, we propose a force-directed method to improve such problems for simplifying the generation of word embedding. In this framework, each word is assumed as a point in the real world; thus it can approximately simulate the physical movement following certain mechanics. To simulate the variation of meaning in phrases, we use the fracture mechanics to do the formation and breakdown of meaning combined by a 2-gram word group. With the experiments on the natural linguistic tasks of part-of-speech tagging, named entity recognition and semantic role labeling, the result demonstrated that the 2-dimensional word embedding can rival the word embeddings generated by classic NLMs, in terms of accuracy, recall, and text visualization.

  6. Mechanical energy generation and transfer in the racket arm during table tennis topspin backhands.

    Science.gov (United States)

    Iino, Yoichi; Kojima, Takeji

    2016-06-01

    The ability to generate a high racket speed and a large amount of racket kinetic energy on impact is important for table tennis players. The purpose of this study was to understand how mechanical energy is generated and transferred in the racket arm during table tennis backhands. Ten male advanced right-handed table tennis players hit topspin backhands against pre-impact topspin and backspin balls. The joint kinetics at the shoulder, elbow and wrist of the racket arm was determined using inverse dynamics. A majority of the mechanical energy of the racket arm acquired during forward swing (65 and 77% against topspin and backspin, respectively) was due to energy transfer from the trunk. Energy transfer by the shoulder joint force in the vertical direction was the largest contributor to the mechanical energy of the racket arm against both spins and was greater against backspin than against topspin (34 and 28%, respectively). The shoulder joint force directed to the right, which peaked just before impact, transferred additional energy to the racket. Our results suggest that the upward thrust of the shoulder and the late timing of the axial rotation of the upper trunk are important for an effective topspin backhand.

  7. Secondhand Tobacco Smoke (Environmental Tobacco Smoke)

    Science.gov (United States)

    Learn about secondhand tobacco smoke, which can raise your risk of lung cancer. Secondhand tobacco smoke is the combination of the smoke given off by a burning tobacco product and the smoke exhaled by a smoker. Also called environmental tobacco smoke, involuntary smoke, and passive smoke.

  8. Computational Models Describing Possible Mechanisms for Generation of Excessive Beta Oscillations in Parkinson's Disease.

    Directory of Open Access Journals (Sweden)

    Alex Pavlides

    2015-12-01

    Full Text Available In Parkinson's disease, an increase in beta oscillations within the basal ganglia nuclei has been shown to be associated with difficulty in movement initiation. An important role in the generation of these oscillations is thought to be played by the motor cortex and by a network composed of the subthalamic nucleus (STN and the external segment of globus pallidus (GPe. Several alternative models have been proposed to describe the mechanisms for generation of the Parkinsonian beta oscillations. However, a recent experimental study of Tachibana and colleagues yielded results which are challenging for all published computational models of beta generation. That study investigated how the presence of beta oscillations in a primate model of Parkinson's disease is affected by blocking different connections of the STN-GPe circuit. Due to a large number of experimental conditions, the study provides strong constraints that any mechanistic model of beta generation should satisfy. In this paper we present two models consistent with the data of Tachibana et al. The first model assumes that Parkinsonian beta oscillation are generated in the cortex and the STN-GPe circuits resonates at this frequency. The second model additionally assumes that the feedback from STN-GPe circuit to cortex is important for maintaining the oscillations in the network. Predictions are made about experimental evidence that is required to differentiate between the two models, both of which are able to reproduce firing rates, oscillation frequency and effects of lesions carried out by Tachibana and colleagues. Furthermore, an analysis of the models reveals how the amplitude and frequency of the generated oscillations depend on parameters.

  9. Smoke detectors

    International Nuclear Information System (INIS)

    Bryant, J.; Howes, J.H.; Smout, D.W.S.

    1979-01-01

    A smoke detector is described which provides a smoke sensing detector and an indicating device and in which a radioactive substance is used in conjunction with two ionisation chambers. The system includes an outer electrode, a collector electrode and an inner electrode which is made of or supports the radioactive substance which, in this case, is 241 Am. The invention takes advantage of the fact that smoke particles can be allowed to enter freely the inner ionisation chamber. (U.K.)

  10. Impact of a cell phone intervention on mediating mechanisms of smoking cessation in individuals living with HIV/AIDS.

    Science.gov (United States)

    Vidrine, Damon J; Arduino, Roberto C; Gritz, Ellen R

    2006-12-01

    Mounting evidence suggests that smokers living with HIV/AIDS have a significantly increased risk of numerous adverse health outcomes (both AIDS- and non-AIDS-related) compared with HIV-positive nonsmokers. Therefore, efforts to design and implement effective cessation programs for this ever-growing special population are warranted. The present study assessed the effects of a cell phone intervention (CPI) on hypothesized mediators (i.e., changes in depression, anxiety, social support, and self-efficacy) demonstrated to influence cessation outcomes in other populations. Ninety-five participants from an inner-city AIDS clinic were randomized to receive either the CPI or recommended standard of care (RSOC) smoking cessation treatment. Participants randomized to the RSOC group (n=47) received brief advice to quit, a 10-week supply of nicotine patches, and self-help materials. Participants randomized to the CPI group (n=48) received RSOC components plus a series of eight proactive counseling sessions delivered via cell phones. A series of regression analyses (linear and logistic) was used to assess the relationships between treatment group, the hypothesized mediators, and biochemically confirmed smoking cessation outcomes. Results indicated that the CPI group experienced greater reductions in anxiety and depression, and increases in self-efficacy compared with the RSOC group. Further, changes in depression, anxiety, and self-efficacy weakened the association between treatment group and cessation outcome. The mediator hypothesis, however, for social support was rejected, as the difference score was not significantly associated with treatment group. These results suggest that the efficacy of the CPI is at least partially mediated by its ability to decrease symptoms of distress while increasing self-efficacy.

  11. Development of simulation technique and examination of mechanism for swelling of steam generator tube

    International Nuclear Information System (INIS)

    Kim, Seon Jin; Kim, Ki Nam; Park, Myung Chul; Shin, Gyeong Su; Cho, Jae Hwan

    2010-05-01

    This study was aimed at identifying the mechanism of the swelling through the development of simulation techniques for the swelling of steam generator tubes and correct understanding of swelling so as to evaluate the effect of swelling on soundness of steam generator based on results of the study. Test apparatus designed to simulate the tube swelling was fabricated and through a number of preliminary experiments at different conditions, swelling simulation was successfully completed. A tube swelling phenomenon is caused by a sort of ratcheting which is analyzable and is considered as a sort of fatigue phenomenon in which the stress is accumulated by action/reaction moment resulting from repeated impact of low energy, despite of hoop stress by internal pressure is significantly lower than yield strength of the material which has effect on hoop stress, overcoming the yield strength and causing the tubes to suffer plastic deformation

  12. Dust generation mechanisms under powerful plasma impacts to the tungsten surfaces in ITER ELM simulation experiments

    International Nuclear Information System (INIS)

    Makhlaj, V.A.; Garkusha, I.E.; Aksenov, N.N.; Chuvilo, A.A.; Chebotarev, V.V.; Landman, I.; Malykhin, S.V.; Pestchanyi, S.; Pugachov, A.T.

    2013-01-01

    In recent tokamak simulation experiments with the QSPA Kh-50 facility several mechanisms of dust generation from tungsten surfaces under ITER ELM-like energy loads have been identified. Here cracking and melting are reported. The brittle destruction dominates after a few transient impacts when a network of major cracks forms on the surface. Bifurcation of major cracks results in ejection of dust particles with sizes up to ∼30 μm. Dust generation occurs also after surface melting and following resolidification when fine crack networks along the grain boundaries develop. In this process the destruction is accompanied by bridge formation due to capillary tension across the fine cracks. Next impacts (even weak melt-free ones) can destroy those bridges, which produces considerable amounts of dust particles of nm-size dust. Surface modification after the repetitive plasma pulses also results in creation of nm-size dust

  13. Control mechanisms in the third-generation planning. Case study: Control to realize sustainable cities

    Science.gov (United States)

    Wicaksono, A. D.

    2017-06-01

    Since the last few years, Indonesia has experienced important events that bring significant changes to the social, political and economic life. The changes directly or indirectly impact the field of planning. With the challenging condition which grows fast and is more complex ahead, and the greater demands on the role of planning, it is required that planning should have higher quality. This paper seeks to answer some questions as follows: (i) How are changes in paradigm and also the development of planning model for the current transition era?, (ii) What is the best way to improve the quality of planning control on the last generation planning model to realize sustainable city?. Analysis steps that will be used to achieve the paper objectives are: (i) Review of planning and sustainable cities theory, (ii) Pattern recognition, (iii) Identifying control mechanisms and sustainable urban forms, (iv) conceptualization. Based on discussion about sustainable cities and control mechanism, some conclusions can be generated as follows: (i) The third generation planning model is based on the theory of expanded system, emphasizing on the constraint of capacity and the ability of planners within the context of larger environment, (ii) There are various theoretical studies that recommend prescriptive model or solution for sustainable urban form and structure. The concepts of Sustainable Cities can be grouped in Neotraditional Development, Urban Containment, Compact City and The Eco-City. The four models above have criteria, namely (i) high density; (ii) a high level of diversity; (iii) mixed land use; (iv) compactness; (5) sustainable transport; (6) passive solar design; (7) Greening Ecological Design. The three main activities in control mechanisms are: Monitoring and Recommendation; a comparative review of the facts (conditions that exist or are developing) with the purpose (expected conditions, set out in urban planning) and recommendations; Evaluation, a review on the

  14. Oxidative Stress: A Unifying Mechanism for Cell Damage Induced by Noise, (Water-Pipe) Smoking, and Emotional Stress-Therapeutic Strategies Targeting Redox Imbalance.

    Science.gov (United States)

    Golbidi, Saeid; Li, Huige; Laher, Ismail

    2018-03-20

    Modern technologies have eased our lives but these conveniences can impact our lifestyles in destructive ways. Noise pollution, mental stresses, and smoking (as a stress-relieving solution) are some environmental hazards that affect our well-being and healthcare budgets. Scrutinizing their pathophysiology could lead to solutions to reduce their harmful effects. Recent Advances: Oxidative stress plays an important role in initiating local and systemic inflammation after noise pollution, mental stress, and smoking. Lipid peroxidation and release of lysolipid by-products, disturbance in activation and function of nuclear factor erythroid 2-related factor 2 (Nrf2), induction of stress hormones and their secondary effects on intracellular kinases, and dysregulation of intracellular Ca 2+ can all potentially trigger other vicious cycles. Recent clinical data suggest that boosting the antioxidant system through nonpharmacological measures, for example, lifestyle changes that include exercise have benefits that cannot easily be achieved with pharmacological interventions alone. Indiscriminate manipulation of the cellular redox network could lead to a new series of ailments. An ideal approach requires meticulous scrutiny of redox balance mechanisms for individual pathologies so as to create new treatment strategies that target key pathways while minimizing side effects. Extrapolating our understanding of redox balance to other debilitating conditions such as diabetes and the metabolic syndrome could potentially lead to devising a unifying therapeutic strategy. Antioxid. Redox Signal. 28, 741-759.

  15. Application of probabilistic fracture mechanics to optimize the maintenance of PWR steam generator tubes

    International Nuclear Information System (INIS)

    Pitner, P.; Riffard, T.

    1993-09-01

    This paper describes the COMPROMIS code developed by Electricite de France (EDF) to optimize the tube bundle maintenance of steam generators (SG). The model, based on probabilistic fracture mechanics, makes it possible to quantify the influence of in-service inspections and maintenance work on the risk of an SG tube rupture, taking all significant parameters into account as random variables (initial defect size distribution, reliability of nondestructive detection and sizing, crack initiation and propagation, critical sizes, leak before risk of break, etc). (authors). 14 figs., 4 tabs., 12 refs

  16. Application of probabilistic fracture mechanics to estimate the risk of rupture of PWR steam generator tubes

    International Nuclear Information System (INIS)

    Pitner, P.; Riffard, T.; Granger, B.

    1992-01-01

    This paper describes the COMPROMIS code developed by Electricite de France (EDF) to optimize the tube bundle maintenance of steam generators. The model, based on probabilistic fracture mechanics, makes it possible to quantify the influence of in-service inspections and maintenance work on the risk of an SG tube rupture, taking all significant parameters into account as random variables (initial defect size distribution, reliability of non-destructive detection and sizing, crack initiation and propagation, critical sizes, leak before risk of break, etc.). (authors). 5 refs., 8 figs., 3 tabs

  17. Flow focusing geometry generates droplets through a plug and squeeze mechanism.

    Science.gov (United States)

    Romero, Philip A; Abate, Adam R

    2012-12-21

    Microdroplets are typically generated by one of two microfluidic geometries, the T-junction and flow focusing. These two geometries are often thought to form drops through different mechanisms. Here, by directly measuring the pressures in the drop maker, we show that flow focus devices exhibit pressure fluctuations that are essentially identical to those found in T-junctions, suggesting that, in these devices and low-to-moderate capillary number, the drop formation process is also dominated by interfacial stresses and proceeds through a plugging-squeezing process.

  18. Study on tsunami damage mechanism in Fukushima Prefecture focusing on the generation of bores

    International Nuclear Information System (INIS)

    Okuma, Shohei; Sato, Shinji; Yamanaka, Yusuke; Sanuki, Hiroshi

    2015-01-01

    Destruction mechanisms of coastal structures due to the 2011 Tohoku Tsunami were investigated on the basis of field surveys in Fukushima Prefecture. Severe destruction appeared to be developed by the action of breaking bores. Laboratory experiments demonstrated that the angle of the tsunami front was an essential parameter for the generation of breaking bores. Larger wave force was observed as the angle of the tsunami front became steeper. Numerical simulation revealed that such a steep tsunami was developed in the central part of Fukushima Prefecture, where the reflection of the preceding tsunami by coastal cliff enhanced the steepness of the largest tsunami. (author)

  19. Deteriorating mechanisms of electric generators; Mecanismos de deterioro de generadores electricos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Tevillo, Arturo; Reyes Martinez, Oscar Alfonso; Robles Pimentel, Edgar Guillermo; Esparza Saucedo, Marcos; Lopez Azamar, Jose Ernesto; Medina Flores, Alfredo; Uribe Martinez, Manuel O. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-12-31

    It is of the greatest importance to know the deteriorating mechanisms that an electric generator undergoes, in order to take corrective measures to stop the process in order to avoid catastrophic damages that imply non scheduled interruptions for maintenance, or inclusively, to carry on the overhaul. In this paper are discussed the deteriorating mechanisms that have been found in the stator (winding and core) and the rotor of thermoelectric and hydroelectric power stations by the natural aging process and abnormal operation. [Espanol] Es de suma importancia conocer los mecanismos de deterioro que sufre un generador, para tomar medidas correctivas que detengan el proceso, con el fin de evitar danos catastroficos que impliquen salidas no programadas para dar mantenimiento, o incluso, para efectuar la rehabilitacion. En este articulo se discuten los mecanismos de deterioro que se han encontrado en el estator (devanado y nucleo) y el rotor de generadores termicos e hidroelectricos por el proceso natural de envejecimiento y por operacion anormal.

  20. Trajectory Generation and Stability Analysis for Reconfigurable Klann Mechanism Based Walking Robot

    Directory of Open Access Journals (Sweden)

    Jaichandar Kulandaidaasan Sheba

    2016-06-01

    Full Text Available Reconfigurable legged robots based on one degree of freedom are highly desired because they are effective on rough and irregular terrains and they provide mobility in such terrain with simple control schemes. It is necessary that reconfigurable legged robots should maintain stability during rest and motion, with a minimum number of legs while maintaining their full range of walking patterns resulting from different gait configuration. In this paper we present a method to generate input trajectory for reconfigurable quadruped robots based on Klann mechanism to properly synchronize movement. Six useful gait cycles based on this reconfigurable Klann mechanism for quadruped robots has been clearly shown here. The platform stability for these six useful gait cycles are validated through simulated results which clearly shows the capabilities of reconfigurable design.

  1. A Theoretical and Experimental Investigation of Mechanical Damage to Rodent Sperm Generated by Microscale Ice Formation.

    Science.gov (United States)

    Han, X; Critser, J K

      BACKGROUND: Rodent sperm cryopreservation is of critical importance for the maintenance of lines or strains of genetically engineered mice and rats. However, rodent sperm are extremely mechanically sensitive due to their unusual morphology, and are severely damaged using current methods of cryopreservation. Those methods result in poor post thaw motility (PTM) for mouse. To investigate the mechanism of mechanical damage introduced to rodent sperm during freezing, a micro-mechanical model was established to analyze the sperm radial and axial thermal stresses generated by microscale extracellular ice formation. PTM of mouse sperm cryopreserved in capillaries of different radii (100, 200, 344, 526, 775µm) was measured using a standard computer-assisted sperm analysis system. The model predicts that when one of the inner dimensions of the containers (the inner diameter of plastic straws or straw capillaries) is on the same order of magnitude of sperm length, axial stress is significantly increased. The experimental results showed that the value of PTM was decreased from 38 ± 8 % in the larger (775µm) capillaries to 0 ± 0 % in the smaller (100 µm) ones. Theoretical analysis based on the established model were experimentally validated and can be used to guide the design of novel devices to improve the efficiency of rodent sperm cryopreservation.

  2. Generating Sub-nanometer Displacement Using Reduction Mechanism Consisting of Torsional Leaf Spring Hinges

    Directory of Open Access Journals (Sweden)

    Fukuda Makoto

    2014-02-01

    Full Text Available Recent demand on the measurement resolution of precise positioning comes up to tens of picometers. Some distinguished researches have been performed to measure the displacement in picometer order, however, few of them can verify the measurement performance as available tools in industry. This is not only because the picometer displacement is not yet required for industrial use, but also due to the lack of standard tools to verify such precise displacement. We proposed a displacement reduction mechanism for generating precise displacement using torsional leaf spring hinges (TLSHs that consist of four leaf springs arranged radially. It has been demonstrated that a prototype of the reduction mechanism was able to provide one-nanometer displacement with 1/1000 reduction rate by a piezoelectric actuator. In order to clarify the potential of the reduction mechanism, a displacement reduction table that can be mounted on AFM stage was newly developed using TLSHs. This paper describes the design of the reduction mechanism and the sub-nanometer displacement performance of the table obtained from its dynamic and static characteristics measured by displacement sensors and from the AFM images

  3. Assessing Smoking Behaviour and Tobacco Smoke Exposure: Definitions and Methods

    Directory of Open Access Journals (Sweden)

    Gregg E

    2014-12-01

    Full Text Available In recent years, the increased availability of tobacco products other than conventional cigarettes, the use of puffing topography devices for smoking behaviour studies and the use of biomarkers to study smoke constituents exposure have generated the need for a more comprehensive set of definitions concerning smoking behaviour and exposure to smoke. The definitions offered in this paper are based on many years of practical experience and on consensus within a broad group of scientists working in these areas. It is intended that, with wider and more consistent usage, these definitions should reduce any misunderstandings and facilitate interpretation of future studies.

  4. Quinones as photosensitizer for photodynamic therapy: ROS generation, mechanism and detection methods.

    Science.gov (United States)

    Rajendran, M

    2016-03-01

    Photodynamic therapy (PDT) is based on the dye-sensitized photooxidation of biological matter in the target tissue, and utilizes light activated drugs for the treatment of a wide variety of malignancies. Quinones and porphyrins moiety are available naturally and involved in the biological process. Quinone metabolites perform a variety of key functions in plants which includes pathogen protection, oxidative phosphorylation, and redox signaling. Quinones and porphyrin are biologically accessible and will not create any allergic effects. In the field of photodynamic therapy, porphyrin derivatives are widely used, because it absorb in the photodynamic therapy window region (600-900 nm). Hence, researchers synthesize drugs based on porphyrin structure. Benzoquinone and its simple polycyclic derivatives such as naphthaquinone and anthraquinones absorb at lower wavelength region (300-400 nm), which is lower than porphyrin. Hence they are not involved in PDT studies. However, higher polycyclic quinones absorb in the photodynamic therapy window region (600-900 nm), because of its conjugation and can be used as PDT agents. Redox cycling has been proposed as a possible mechanism of action for many quinone species. Quinones are involved in the photodynamic as well as enzymatic generation of reactive oxygen species (ROS). Generations of ROS may be measured by optical, phosphorescence and EPR methods. The photodynamically generated ROS are also involved in many biological events. The photo-induced DNA cleavage by quinones correlates with the ROS generating efficiencies of the quinones. In this review basic reactions involving photodynamic generation of ROS by quinones and their biological applications were discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Accumulation mechanism of tight sandstone gas in low gas generation intensity area

    Directory of Open Access Journals (Sweden)

    Fudong Zhang

    2017-04-01

    Full Text Available Before 11th five-year plan, geologists proposed the viewpoint that the gas generation intensity that's more than 20 × 108 m3/km2 was an important condition for forming conventional large gas fields. However, recent exploration findings indicate that large-area tight sandstone gas that has a gas generation intensity of less than 20 × 108 m3/km2 can still form reserves. This is an area worth exploring. Through innovative accumulation simulation, microscopic pore throat analysis of reservoirs, and dissection of typical gas reservoirs, several factors have been established, including the comprehensive evaluation models involving gas charging pressure, reservoir physical properties, and lower gas generation limit. In addition, the paper has made it certain that the tight sandstone gas in a low gas generation intensity area has accumulation characteristics such as “partial water displacing, long-term gas supply, gas control by tight reservoirs of scale, gas abundance control by physical properties, combined control and enrichment of dominant resources, etc.”, and has proposed the viewpoint that this area has the accumulation mechanism that of a “non-dominant transportation, long-term continuous charging, reservoir controlling by physical property difference, and enrichment in partial sweet spots” and shows discontinuous “patchy distribution” on the plane. This is of much significance to fine exploration and development of the trillion cubic meter resources of the low gas generation intensity areas in the west of Sulige gas field.

  6. SECOND GENERATION MOSAIC:A NOVEL MECHANISM BASED ON REFERENCE DATABASE FOR MAP UPDATING

    Directory of Open Access Journals (Sweden)

    G. Hu

    2012-08-01

    Full Text Available A totally new automatic workflow mechanism, named Second generation Mosaic module, based on the well-known Pixel Factory system, will be introduced here, which enables existing digital orthoimages and mosaics to be quickly updated. The process extracts all required parameters from the reference database to be able to perform automatic bundle adjustment and radiometric adaptation.In this paper, two examples for both satellite data and aerial data processed based on this mechanism will be presented here and discussed. Finally, the cost reduction will also be analysed according to the real mapping updating project.In a final statement, this paper will present an integrated solution named second generation mosaic module based on the well-known Pixel Factory system which is completely dedicated to fast processing of photogrammetric products Thanks to this integrated hardware and software solution, it is even possible to manage large data volume quickly in order to have precise map updating information as soon as possible after acquisition.

  7. Study on thermal and mechanical properties of U-tube materials for steam generator

    International Nuclear Information System (INIS)

    Rheu, Woo Suk; Kang, Young Hwan; Park, Jong Man; Joo, Ki Nam; Kim, Sung Soo; Maeng, Wan Young; Park, Se Jin

    1993-01-01

    Most of domestic nuclear plants have used I600 TT material for steam generator U-tube, and piled up the field experience. I600 HTMA and I690 TT, however, are recommended for an alternative of U-tube by ABB-CE since YK-3 and 4. Field experience of I600 HTMA and I690 TT have not compiled in the country, so it is concerned to select the future materials for U-tube. Thus, database on the thermal and mechanical properties of U-tube materials is very necessary for design documentations. In this study, the thermal, mechanical and metallugical properties were tested and evaluated to establish the database for steam generator U-tube. In addition, thermal conductivity of I600 and I690 was measured and compared statistically, providing a basic document for applying I690 to U-tube. The results will be used to improve the manufacturing process in order to increase the integrity of U-tube. (Author)

  8. Potential of different mechanical and thermal treatments to control off-flavour generation in broccoli puree.

    Science.gov (United States)

    Koutidou, Maria; Grauwet, Tara; Van Loey, Ann; Acharya, Parag

    2017-02-15

    The aim of this study was scientifically investigate the impact of the sequence of different thermo-mechanical treatments on the volatile profile of differently processed broccoli puree, and to investigate if any relationship persists between detected off-flavour changes and microstructural changes as a function of selected process conditions. Comparison of the headspace GC-MS fingerprinting of the differently processed broccoli purees revealed that an adequate combination of processing steps allows to reduce the level of off-flavour volatiles. Moreover, applying mechanical processing before or after the thermal processing at 90°C determines the pattern of broccoli tissue disruption, resulting into different microstructures and various enzymatic reactions inducing volatile generation. These results may aid the identification of optimal process conditions generating a reduced level of off-flavour in processed broccoli. In this way, broccoli can be incorporated as a food ingredient into mixed food products with limited implications on sensorial consumer acceptance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. An Experimental Investigation of Wind- and Mechanically Generated Short Wavelength Spilling Breakers

    Science.gov (United States)

    Diorio, J. D.; Liu, X.; Duncan, J. H.

    2006-11-01

    Short wavelength spilling breakers are studied in a wind wave tank that is 12.8 m long and 1.15 m wide and 0.91 m deep. The crest profile histories during breaking are measured with a photographic technique that employs a high-speed digital movie camera, a laser light sheet, and fluorescent dye. The photographic system is mounted on an instrument carriage that is set to move along the tank in phase with the crests of the breaking waves. In the first step in the experiment, breakers generated by the wind are measured at three wind speeds and three fetches at each wind speed. In the second step in the experiment, a mechanical wave maker is used without wind to generate a wave train consisting of a dominant wave and two unstable sidebands. The amplitudes and frequencies of these wave components are adjusted to create breakers at the various fetches and dominant wave frequencies found in the wind wave experiments. The similarities and differences between the ripple patterns at the crest during breaking between the wind wave and mechanical wave cases are discussed.

  10. Undulations in a weakly interacting mechanically generated molecular braid under tension

    International Nuclear Information System (INIS)

    O’ Lee, D J

    2014-01-01

    We consider mechanically generated molecular braids composed of two molecules where long range interactions between them can be considered to be very weak. We describe a model that takes account of the thermal fluctuations of the braid, steric interactions between the molecules, and external mechanical forces. In this model, both sets of ends, of the two molecules, are considered to be separated by a fixed distance much larger than the radius of the braid. One set of ends is rotated to generate a braid of a certain number of pitches (or turns), while the other set remains fixed. This model may describe the situation in which the ends of each molecule are attached to a substrate and a magnetic bead; to the latter a pulling force and rotational torque can be applied. We discuss various aspects of our model. Most importantly, an expression for the free energy is given, from which equations, determining the various geometric parameters of the braid, can be obtained. By numerically solving these equations, we give predictions from the model for the external torque needed to produce a braid with a certain number of turns per bending persistence length, as well as the end to end extension of the two molecules for a given pulling force. Other geometric parameters, as well as the lateral force required to keep the ends of the two molecules apart, are also calculated. (paper)

  11. Mechanisms of generation of local ΔpH in mitochondria and bacteria.

    Science.gov (United States)

    Medvedev, E S; Stuchebrukhov, A A

    2014-05-01

    The concepts of global and local coupling between proton generators, the enzymes of the respiratory chain, and the consumer, the ATP synthase, coexist in the theory of oxidative phosphorylation. Global coupling is trivial proton transport via the aqueous medium, whereas local coupling implies that the protons pumped are consumed before they escape to the bulk phase. In this work, the conditions for the occurrence of local coupling are explored. It is supposed that the membrane retains protons near its surface and that the proton current generated by the proton pumps rapidly decreases with increasing proton motive force (pmf). It is shown that the competition between the processes of proton translocation across the membrane and their dissipation from the surface to the bulk can result in transient generation of a local ΔpH in reply to a sharp change in pmf; the appearance of local ΔpH, in turn, leads to rapid recovery of the pmf, and hence, it provides for stabilization of the potential at the membrane. Two mechanisms of such kind are discussed: 1) pH changes in the surface area due to proton pumping develop faster than those due to proton escape to the bulk; 2) the former does not take place, but the protons leaving the surface do not equilibrate with the bulk immediately; rather, they give rise to a non-equilibrium concentration near the surface and, as a result, to a back proton flow to the surface. The first mechanism is more efficient, but it does not occur in mitochondria and neutrophilic bacteria, whereas the second can produce ΔpH on the order of unity. In the absence of proton retardation at the surface, local ΔpH does not arise, whereas the formation of global ΔpH is possible only at buffer concentration of less than 10 mM. The role of the mechanisms proposed in transitions between States 3 and 4 of the respiratory chain is discussed. The main conclusion is that surface protons, under conditions where they play a role, support stabilization of the

  12. Secondhand Smoke

    Science.gov (United States)

    ... 5 (43.2%) nonsmokers who lived below the poverty level were exposed to secondhand smoke. Occupation 10 Differences in secondhand smoke exposure related to people’s jobs decreased over the past 20 years, but large differences still exist. Some groups continue to have high levels of ...

  13. A study on the deformation mechanism of inconel alloys for steam generator tubes

    Energy Technology Data Exchange (ETDEWEB)

    Hong, S. H.; Kim, H. Y.; Ahn, Y. C.; Lee, H. S.; Sohn, W. H.; Cha, S. I.; Bae, Y. H. [Korea Advanced Institute of Science and Technology, Taejeon (Korea)

    2001-04-01

    The microstructure and the mechanical properties of lnconel 600 and 690 steam generator tube were investigated to develop the lnconel steam generator tube for nuclear power plant. The grain size and shape of lnconel 690 alloy were dependent on Mill Annealing temperature. It is shown that the smaller grain and the more serrated grain boundary, the higher tensile strength and creep resistance. The carbides were analyzed by using SEM and TEM after Thermal Treatment. Also, the quantitative analysis of carbide precipitation with Thermal Treatment was conducted by SPEED method. Thermal Treatment temperature was 705 deg C for lnconel 600 alloy and 720 deg C for lnconel 690 alloy. It is observed by XRD that the M{sub 23}C{sub 6} type and M{sub 7}C{sub 3}-type carbides were simultaneously precipitated in lnconel 600 alloy and only M{sub 23}C{sub 6}-type carbides were precipitated in lnconel 690 alloy. While the carbide length and thickness increased with increasing Thermal Treatment time, the growth rate of carbide length was higher than that of carbide thickness. The distance between carbides decreased for the first 15 hour Thermal Treatment for lnconel 600 alloy and 10 hour for lnconel 690 alloy, respectively, and then increased again. The distance between carbides decreased until the carbide precipitation reached at 90% of maximum precipitation because the carbides were precipitated and grown simultaneously. After 90% precipitation time, the precipitation ceased and only growth of the carbides took place, so the distance between carbides decreased. The serrations in stress-strain curves of in lnconel 690 could be interpreted in the temperature range from 200 deg C to 600 deg C. The phenomena and controlling mechanism of serrations were analyzed by investigating the critical strains for the onset of the serrations. The controlling mechanism for A1 serration was generation of vacancy by deformation, and those for A2 serration and B serrations were diffusion of

  14. The grand unified link between the Peccei-Quinn mechanism and the generation puzzle

    International Nuclear Information System (INIS)

    Davidson, A.; Wali, K.C.

    1982-03-01

    The essential ingredients of the Peccei-Quinn mechanism are shown to be dictated by a proper choice of a grand unification scheme. The presence of U(1)sub(PQ) gives rise to the possibility that the same physics which resolves the strong CP-violation problem may decode the generation puzzle with no extra cost. Multigenerational signatures of the invisible axion scenario, such as the canonical fermion mass matrix, are discussed. The uniqueness and the special values of the quantized PQ-assignments, namely 1,-3,5-7,... for successive generations, acquire an automatic explanation once the idea of ''horizontal compositeness'' is invoked. A characteristic feature then is that the muon appears to have a less complicated structure than the electron. Furthermore, U(1)sub(PQ) chooses SO(10) to be its only tenable gauge symmetry partner, and at the same time crucially restricts the associated Higgs system. All this finally results in a consistent fermion mass hierarchy with log m, to the crudest estimation, varying linearly with respect to the generation index. (author)

  15. Possible Mechanism for the Generation of a Fundamental Unit of Charge (long version)

    Energy Technology Data Exchange (ETDEWEB)

    Lestone, John Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-06-16

    Various methods for calculating particle-emission rates from hot systems are reviewed. Semi-classically derived photon-emission rates often contain the term exp(-ε/T) which needs to be replaced with the corresponding Planckian factor of [exp(-ε/T)-1]-1 to obtain the correct rate. This replacement is associated with the existence of stimulated emission. Simple arguments are used to demonstrate that black holes can also undergo stimulated emission, as previously determined by others. We extend these concepts to fundamental particles, and assume they can be stimulated to emit virtual photons with a cross section of πλ2, in the case of an isolated particle when the incident virtual-photon energy is < 2πmc2. Stimulated-virtual photons can be exchanged with other particles generating a force. With the inclusion of near-field effects, the model choices presented give a calculated fundamental unit of charge of 1.6022x10-19 C. If these choices are corroborated by detailed calculations then an understanding of the numerical value of the fine structure constant may emerge. The present study suggests charge might be an emergent property generated by a simple interaction mechanism between point-like particles and the electromagnetic vacuum, similar to the process that generates the Lamb shift.

  16. Generation mechanism of RANKL(+) effector memory B cells: relevance to the pathogenesis of rheumatoid arthritis.

    Science.gov (United States)

    Ota, Yuri; Niiro, Hiroaki; Ota, Shun-Ichiro; Ueki, Naoko; Tsuzuki, Hirofumi; Nakayama, Tsuyoshi; Mishima, Koji; Higashioka, Kazuhiko; Jabbarzadeh-Tabrizi, Siamak; Mitoma, Hiroki; Akahoshi, Mitsuteru; Arinobu, Yojiro; Kukita, Akiko; Yamada, Hisakata; Tsukamoto, Hiroshi; Akashi, Koichi

    2016-03-16

    The efficacy of B cell-depleting therapies for rheumatoid arthritis underscores antibody-independent functions of effector B cells such as cognate T-B interactions and production of pro-inflammatory cytokines. Receptor activator of nuclear factor κB ligand (RANKL) is a key cytokine involved in bone destruction and is highly expressed in synovial fluid B cells in patients with rheumatoid arthritis. In this study we sought to clarify the generation mechanism of RANKL(+) effector B cells and their impacts on osteoclast differentiation. Peripheral blood and synovial fluid B cells from healthy controls and patients with rheumatoid arthritis were isolated using cell sorter. mRNA expression of RANKL, osteoprotegerin, tumor necrosis factor (TNF)-α, and Blimp-1 was analyzed by quantitative real-time polymerase chain reaction. Levels of RANKL, CD80, CD86, and CXCR3 were analyzed using flow cytometry. Functional analysis of osteoclastogenesis was carried out in the co-culture system using macrophage RAW264 reporter cells. RANKL expression was accentuated in CD80(+)CD86(+) B cells, a highly activated B-cell subset more abundantly observed in patients with rheumatoid arthritis. Upon activation via B-cell receptor and CD40, switched-memory B cells predominantly expressed RANKL, which was further augmented by interferon-γ (IFN-γ) but suppressed by interleukin-21. Strikingly, IFN-γ also enhanced TNF-α expression, while it strongly suppressed osteoprotegerin expression in B cells. IFN-γ increased the generation of CXCR3(+)RANKL(+) effector B cells, mimicking the synovial B cell phenotype in patients with rheumatoid arthritis. Finally, RANKL(+) effector B cells in concert with TNF-α facilitated osteoclast differentiation in vitro. Our current findings have shed light on the generation mechanism of pathogenic RANKL(+) effector B cells that would be an ideal therapeutic target for rheumatoid arthritis in the future.

  17. Insights into the mechanisms of absence seizure generation provided by EEG with Functional MRI.

    Directory of Open Access Journals (Sweden)

    Patrick William Carney

    2014-09-01

    Full Text Available Absence seizures are brief epileptic events characterized by loss of awareness with subtle motor features. They may be very frequent, and impact on attention, learning and memory. A number of pathophysiological models have been developed to explain the mechanism of absence seizure generation which rely heavily on observations from animal studies. Studying the structural and functional relationships between large-scale brain networks in humans is only practical with non-invasive whole brain techniques. EEG with functional MRI (EEG-fMRI is one such technique that provides an opportunity to explore the interactions between brain structures involved in AS generation. A number of fMRI techniques including event-related analysis, time course analysis and functional connectivity have identified a common network of structures involved in AS seizures. This network comprises the thalamus, midline and lateral parietal cortex (the default mode network [DMN], caudate nuclei and the reticular structures of the pons. The main component displaying an increase in BOLD signal relative to the resting state, in group studies, is the thalamus while the most consistent cortical change is reduced BOLD signal in the DMN. Time course analysis shows that, rather than some structures being activated or inactivated during AS, there appears to be increase in activity across components of the network preceding or following the electro-clinical onset of the seizure. The earliest change in BOLD signal occurs in the DMN, prior to the onset of epileptiform events. This region also shows altered functional connectivity in patients with absence seizures. Hence it appears that engagement of this network is central to absence seizures. In this review we will explore the insights EEG-fMRI studies into the mechanisms of AS and considers how the DMN is likely to be the major large scale brain network central to both seizure generation and the seizure manifestations.

  18. Engineering mechanical gradients in next generation biomaterials - Lessons learned from medical textile design.

    Science.gov (United States)

    Ng, Joanna L; Collins, Ciara E; Knothe Tate, Melissa L

    2017-07-01

    Nonwoven and textile membranes have been applied both externally and internally to prescribe boundary conditions for medical conditions as diverse as oedema and tissue defects. Incorporation of mechanical gradients in next generation medical membrane design offers great potential to enhance function in a dynamic, physiological context. Yet the gradient properties and resulting mechanical performance of current membranes are not well described. To bridge this knowledge gap, we tested and compared the mechanical properties of bounding membranes used in both external (compression sleeves for oedema, exercise bands) and internal (surgical membranes) physiological contexts. We showed that anisotropic compression garment textiles, isotropic exercise bands and surgical membranes exhibit similar ranges of resistance to tension under physiologic strains. However, their mechanical gradients and resulting stress-strain relationships show differences in work capacity and energy expenditure. Exercise bands' moduli of elasticity and respective thicknesses allow for controlled, incremental increases in loading to facilitate healing as injured tissues return to normal structure and function. In contrast, the gradients intrinsic to compression sleeve design exhibit gaps in the middle range (1-5N) of physiological strains and also inconsistencies along the length of the sleeve, resulting in less than optimal performance of these devices. These current shortcomings in compression textile and garment design may be addressed in the future through implementation of novel approaches. For example, patterns, fibre compositions, and fibre anisotropy can be incorporated into biomaterial design to achieve seamless mechanical gradients in structure and resulting dynamic function, which would be particularly useful in physiological contexts. These concepts can be applied further to biomaterial design to deliver pressure gradients during movement of oedematous limbs (compression garments) and

  19. Evaluation of the user interface simplicity in the modern generation of mechanical ventilators.

    Science.gov (United States)

    Uzawa, Yoshihiro; Yamada, Yoshitsugu; Suzukawa, Masayuki

    2008-03-01

    We designed this study to evaluate the simplicity of the user interface in modern-generation mechanical ventilators. We hypothesized that different designs in the user interface could result in different rates of operational failures. A laboratory in a tertiary teaching hospital. Crossover design. Twenty-one medical resident physicians who did not possess operating experience with any of the selected ventilators. Four modern mechanical ventilators were selected: Dräger Evita XL, Maquet Servo-i, Newport e500, and Puritan Bennett 840. Each subject was requested to perform 8 tasks on each ventilator. Two objective variables (the number of successfully completed tasks without operational failures and the operational time) and the overall subjective rating of the ease of use, measured with a 100-mm visual analog scale were recorded. The total percentage of operational failures made for all subjects, for all tasks, was 23%. There were significant differences in the rates of operational failures and operational time among the 4 ventilators. Subjects made more operational failures in setting up the ventilators and in making ventilator-setting changes than in reacting to alarms. The subjective feeling of the ease of use was also significantly different among the ventilators. The design of the user interface is relevant to the occurrence of operational failures. Our data indicate that ventilator designers could optimize the user-interface design to reduce the operational failures; therefore, basic user interface should be standardized among the clinically used mechanical ventilators.

  20. The generation and management of references with the Online Mechanism for References - MORE

    Directory of Open Access Journals (Sweden)

    Proxério Manoel Felisberto

    2015-04-01

    Full Text Available The scientific production and the development of academic papers have their own formalities. In this paper, is sought seek from these formalities for the ones that refers to the way of granting merits to the authors of the works used in the theoretical basis, through quotations and references. The goal is to help users of libraries to generate and manage references using a web tool developed for this purpose. There are many applications, in desktop and web platforms, that could be used to do this task. However, some of them require the payment of an expensive license to be fully functional. Others offers free versions, but they are very limited and often do not generate references specified by ABNT. There are others that do not store the generate references for later use. In order to fill this gap, the Online Mechanism for References (MORE was developed and made available to the general public in the web. Even so, the fast technological advances combined with a high number of users demanded an update to the application, done recently. It is important to state that all the work was developed exclusively with proven and free to use technologies. Initially, sought up identified the main tools available to generate and manage references and which free technologies could be used to build interactive web applications. This paper briefly describes the reengineering process that MORE was submitted, its new structure, new requirements met and its expanded portfolio of features. Finally, the results achieved after the reengineering are compared to indicators of its previous version.

  1. A Facile Method and Novel Mechanism Using Microneedle-Structured PDMS for Triboelectric Generator Applications.

    Science.gov (United States)

    Trinh, Van-Long; Chung, Chen-Kuei

    2017-08-01

    The triboelectric generator (TEG) is a cost-effective, multi-fabricated, friendly mechanical-energy-harvesting device. The traditional TEG, generally formed by two triboelectric materials in multilayers or a simple pattern, generated triboelectricity as it worked in the cycling contact-separation operation. This paper demonstrates a novel, high-aspect-ratio, microneedle (MN)-structured polydimethylsiloxane (PDMS)-based triboelectric generator (MN-TEG) by means of a low-cost, simple fabrication using CO 2 laser ablation on the polymethyl methacrylate substrate and a molding process. The MN-TEG, consisting of an aluminum foil and a microneedle-structured PDMS (MN-PDMS) film, generates an output performance with an open-circuit voltage up to 102.8 V, and a short-circuit current of 43.1 µA, corresponding to the current density of 1.5 µA cm -2 . With introducing MN-PDMS into the MN-TEG, a great increase of randomly closed bending-friction-deformation (BFD) behavior of MNs leads to highly enhanced triboelectric performance of the MN-TEG. The BFD keeps increasingly on in-contact between MN with Al that results in enhancement of electrical capacitance of PDMS. The effect of aspect ratio and density of MN morphology on the output performance of MN-PDMS TEG is studied further. The MN-TEG can rapidly charge electric energy on a 0.1 µF capacitor up to 2.1 V in about 0.56 s. The MN-TEG source under tapping can light up 53 light-emitting diodes with different colors, connected in series. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Examination of incentive mechanisms for innovative technologies applicable to utility and nonutility power generators

    Energy Technology Data Exchange (ETDEWEB)

    McDermott, K.A. [Illinois Commerce Commission, Springfield, IL (United States); Bailey, K.A.; South, D.W. [Argonne National Lab., IL (United States). Environmental Assessment and Information Sciences Div.

    1993-08-01

    Innovative technologies, built by either utility or nonutility power generators, have the potential to lower costs with less environmental emissions than conventional technologies. However, the public-good nature of information, along with uncertain costs, performance, and reliability, discourages rapid adoption of these technologies. The effect of regulation of electricity production may also have an adverse impact on motivation to innovate. Slower penetration of cleaner, more efficient technologies could result in greater levels of pollution, higher electricity prices, and a reduction in international competitiveness. Regulatory incentives could encourage adoption and deployment of innovative technologies of all kinds, inducting clean coal technologies. Such incentives must be designed to offset risks inherent in innovative technology and encourage cost-effective behavior. To evaluate innovative and conventional technologies equally, the incremental cost of risk (ICR) of adopting the innovative technology must be determined. Through the ICR, the magnitude of incentive required to make a utility (or nonutility) power generator equally motivated to use either conventional or innovative technologies can be derived. Two technology risks are examined: A construction risk, represented by a 15% cost overrun, and an operating risk, represented by a increased forced outage rate (decreased capacity factor). Different incentive mechanisms and measurement criteria are used to assess the effects of these risks on ratepayers and shareholders. In most cases, a regulatory incentive could offset the perceived risks while encouraging cost-effective behavior by both utility and nonutility power generators. Not only would the required incentive be recouped, but the revenue requirements would be less for the innovative technology; also, less environmental pollution would be generated. In the long term, ratepayers and society would benefit from innovative technologies.

  3. Explicit polarization: a quantum mechanical framework for developing next generation force fields.

    Science.gov (United States)

    Gao, Jiali; Truhlar, Donald G; Wang, Yingjie; Mazack, Michael J M; Löffler, Patrick; Provorse, Makenzie R; Rehak, Pavel

    2014-09-16

    Conspectus Molecular mechanical force fields have been successfully used to model condensed-phase and biological systems for a half century. By means of careful parametrization, such classical force fields can be used to provide useful interpretations of experimental findings and predictions of certain properties. Yet, there is a need to further improve computational accuracy for the quantitative prediction of biomolecular interactions and to model properties that depend on the wave functions and not just the energy terms. A new strategy called explicit polarization (X-Pol) has been developed to construct the potential energy surface and wave functions for macromolecular and liquid-phase simulations on the basis of quantum mechanics rather than only using quantum mechanical results to fit analytic force fields. In this spirit, this approach is called a quantum mechanical force field (QMFF). X-Pol is a general fragment method for electronic structure calculations based on the partition of a condensed-phase or macromolecular system into subsystems ("fragments") to achieve computational efficiency. Here, intrafragment energy and the mutual electronic polarization of interfragment interactions are treated explicitly using quantum mechanics. X-Pol can be used as a general, multilevel electronic structure model for macromolecular systems, and it can also serve as a new-generation force field. As a quantum chemical model, a variational many-body (VMB) expansion approach is used to systematically improve interfragment interactions, including exchange repulsion, charge delocalization, dispersion, and other correlation energies. As a quantum mechanical force field, these energy terms are approximated by empirical functions in the spirit of conventional molecular mechanics. This Account first reviews the formulation of X-Pol, in the full variationally correct version, in the faster embedded version, and with systematic many-body improvements. We discuss illustrative examples

  4. Study of an ionic smoke sensor

    International Nuclear Information System (INIS)

    Mokhtari, Z; Holé, S; Lewiner, J

    2013-01-01

    Ionization smoke sensors are among the best smoke sensors; however, the little radioactive source they include is no longer desirable since it makes recycling more complicated. In this paper, we discuss an electrostatic system in which a corona discharge is used to generate the ions needed for smoke detection. We show how the velocity of ions is reduced in our system for a better interaction between smoke and drifting ions. The influence of smoke, temperature and moisture is studied. It is shown that the proposed sensor has good sensitivity compared with conventional ionic and optical smoke sensors. (paper)

  5. Apoptosis generates mechanical forces that close the lens vesicle in the chick embryo

    Science.gov (United States)

    Oltean, Alina; Taber, Larry A.

    2018-03-01

    During the initial stages of eye development, optic vesicles grow laterally outward from both sides of the forebrain and come into contact with the surrounding surface ectoderm (SE). Within the region of contact, these layers then thicken locally to create placodes and invaginate to form the optic cup (primitive retina) and lens vesicle (LV), respectively. This paper examines the biophysical mechanisms involved in LV formation, which consists of three phases: (1) lens placode formation; (2) invagination to create the lens pit (LP); and (3) closure to form a complete ellipsoidally shaped LV. Previous studies have suggested that extracellular matrix deposited between the SE and optic vesicle causes the lens placode to form by locally constraining expansion of the SE as it grows, while actomyosin contraction causes this structure to invaginate. Here, using computational modeling and experiments on chick embryos, we confirm that these mechanisms for Phases 1 and 2 are physically plausible. Our results also suggest, however, that they are not sufficient to close the LP during Phase 3. We postulate that apoptosis provides an additional mechanism by removing cells near the LP opening, thereby decreasing its circumference and generating tension that closes the LP. This hypothesis is supported by staining that shows a ring of cell death located around the LP opening during closure. Inhibiting apoptosis in cultured embryos using caspase inhibitors significantly reduced LP closure, and results from a finite-element model indicate that closure driven by cell death is plausible. Taken together, our results suggest an important mechanical role for apoptosis in lens development.

  6. Stop smoking support programs

    Science.gov (United States)

    Smokeless tobacco - stop smoking programs; Stop smoking techniques; Smoking cessation programs; Smoking cessation techniques ... You can find out about smoking cessation programs from: Your ... Your employer Your local health department The National Cancer ...

  7. Smoking during Pregnancy

    Science.gov (United States)

    ... Home > Pregnancy > Is it safe? > Smoking during pregnancy Smoking during pregnancy E-mail to a friend Please ... smoking, tell your health care provider. Why is smoking during pregnancy harmful? Smoking during pregnancy is bad ...

  8. Generation and Decay Mechanisms of Ningaloo Niño/Niña

    Science.gov (United States)

    Kataoka, Takahito; Tozuka, Tomoki; Yamagata, Toshio

    2017-11-01

    Using an ocean model, generation and decay mechanisms of warm/cool sea surface temperature anomalies (SSTAs) off Western Australia, or Ningaloo Niño/Niña, are investigated through the calculation of a mixed-layer temperature (MLT) balance taking the mixed-layer depth (MLD) variation into account. Since Ningaloo Niño/Niña develops owing to local air-sea interaction and/or remote forcing, events are classified into two cases based on alongshore wind anomalies and analyzed separately. It is revealed that the anomalous meridional advection associated with the stronger Leeuwin Current and the enhanced warming by the climatological shortwave radiation because of the shallower MLD generate warm SSTAs in the coastal region for both cases of Ningaloo Niño. On the other hand, the latent heat flux damps SSTAs only in a case without northerly alongshore wind anomalies. In the decay, larger sensible heat loss is important. Because of the reduced meridional temperature gradient, the meridional advection eventually damps SSTAs. The sensitivity change to the climatological shortwave radiation owing to MLD anomalies explains offshore MLT tendency anomalies for both cases throughout the events. The mechanisms for Ningaloo Niña are close to a mirror image of Ningaloo Niño but differ in that the latent heat flux damps offshore SSTAs. The seasonal phase-locking nature of Ningaloo Niño/Niña is related to the seasonal variations of MLD and surface heat fluxes, which regulate the amplitude and sign of the sensitivity change to surface heat fluxes. It is also related to the seasonal variations of the Leeuwin Current and meridional temperature gradient through advection anomalies.

  9. Research and Improvement on Characteristics of Emergency Diesel Generating Set Mechanical Support System in Nuclear Power Plant

    Science.gov (United States)

    Zhe, Yang

    2017-06-01

    There are often mechanical problems of emergency power generation units in nuclear power plant, which bring a great threat to nuclear safety. Through analyzing the influence factors caused by mechanical failure, the existing defects of the design of mechanical support system are determined, and the design idea has caused the direction misleading in the field of maintenance and transformation. In this paper, research analysis is made on basic support design of diesel generator set, main pipe support design and important components of supercharger support design. And this paper points out the specific design flaws and shortcomings, and proposes targeted improvement program. Through the implementation of improvement programs, vibration level of unit and mechanical failure rate are reduced effectively. At the same time, it also provides guidance for design, maintenance and renovation of diesel generator mechanical support system of nuclear power plants in the future.

  10. Investigation of the sound generation mechanisms for in-duct orifice plates.

    Science.gov (United States)

    Tao, Fuyang; Joseph, Phillip; Zhang, Xin; Stalnov, Oksana; Siercke, Matthias; Scheel, Henning

    2017-08-01

    Sound generation due to an orifice plate in a hard-walled flow duct which is commonly used in air distribution systems (ADS) and flow meters is investigated. The aim is to provide an understanding of this noise generation mechanism based on measurements of the source pressure distribution over the orifice plate. A simple model based on Curle's acoustic analogy is described that relates the broadband in-duct sound field to the surface pressure cross spectrum on both sides of the orifice plate. This work describes careful measurements of the surface pressure cross spectrum over the orifice plate from which the surface pressure distribution and correlation length is deduced. This information is then used to predict the radiated in-duct sound field. Agreement within 3 dB between the predicted and directly measured sound fields is obtained, providing direct confirmation that the surface pressure fluctuations acting over the orifice plates are the main noise sources. Based on the developed model, the contributions to the sound field from different radial locations of the orifice plate are calculated. The surface pressure is shown to follow a U 3.9 velocity scaling law and the area over which the surface sources are correlated follows a U 1.8 velocity scaling law.

  11. Gas Supply, Pricing Mechanism and the Economics of Power Generation in China

    Directory of Open Access Journals (Sweden)

    Yuanxin Liu

    2018-04-01

    Full Text Available During the “13th Five-Year Plan” period, green energy is the top priority for China. China has realized that natural gas, as a low-carbon energy source, fits with the nation’s energy demand and will play a critical role in the energy transition, but the actual industry development is slower than expected. By analyzing the major gas corporations around the world, the paper finds that the key factors of the sector are supply and price of the energy resource. A comprehensive analysis on domestic and foreign imported gas reveals a trend of oversupply in China in the future. Given the critical import dependence, China has introduced a series of gas price reforms since 2013, which have led to negative impacts on important gas consumption sectors including power generation. With the levelized cost of electricity (LCOE model, we find that under the prevailing gas supply structure and price level, the economy of utility gas power generation will remain unprofitable, while combined cooling heating and power (CCHP is only commercially feasible in coastal developed regions. If continuing, such a trend will not only bring forth disastrous consequences to gas power industry, but also damage the upstream gas industry, more importantly, impede the energy transition. We conclude the paper with policy implications on pricing mechanism reform, developing domestic unconventional gas and the R&D of gas turbine.

  12. Conserved mechanisms of microtubule-stimulated ADP release, ATP binding, and force generation in transport kinesins.

    Science.gov (United States)

    Atherton, Joseph; Farabella, Irene; Yu, I-Mei; Rosenfeld, Steven S; Houdusse, Anne; Topf, Maya; Moores, Carolyn A

    2014-09-10

    Kinesins are a superfamily of microtubule-based ATP-powered motors, important for multiple, essential cellular functions. How microtubule binding stimulates their ATPase and controls force generation is not understood. To address this fundamental question, we visualized microtubule-bound kinesin-1 and kinesin-3 motor domains at multiple steps in their ATPase cycles--including their nucleotide-free states--at ∼ 7 Å resolution using cryo-electron microscopy. In both motors, microtubule binding promotes ordered conformations of conserved loops that stimulate ADP release, enhance microtubule affinity and prime the catalytic site for ATP binding. ATP binding causes only small shifts of these nucleotide-coordinating loops but induces large conformational changes elsewhere that allow force generation and neck linker docking towards the microtubule plus end. Family-specific differences across the kinesin-microtubule interface account for the distinctive properties of each motor. Our data thus provide evidence for a conserved ATP-driven mechanism for kinesins and reveal the critical mechanistic contribution of the microtubule interface.

  13. Mitigation of Shear-Induced Blood Damage of Mechanical Bileaflet Heart Valves using Embedded Vortex Generators

    Science.gov (United States)

    Hidalgo, Pablo; Arjunon, Sivakkumar; Saikrishnan, Neelakantan; Yoganathan, Ajit; Glezer, Ari

    2012-11-01

    The strong transitory shear stress generated during the time-periodic closing of the mechanical prosthetic bileaflet aortic heart valve, is considered to be one of the main factors responsible for complications, associated with thrombosis and thromboembolism. These flow transients are investigated using phase and time-averaged PIV in a low-volume (about 150 ml) test setup that simulates the pulsatile physiological conditions associated with a 23 mm St. Jude Medical valve. The PIV measurements are accompanied by continuous monitoring of the ventricular and aortic pressures and valve flow rate. Following the valve closure, the leakage flow between the valve leaflets is caused by the pressure buildup across the leaflets, leading to the formation of a regurgitation jet starting from the BMHV B-datum line. As in a typical starting jet, a counter-rotating vortex pair is formed along each leaflet edge and the vorticity sheet is associated with high shear stress that may be result in blood platelet activation. The present investigation demonstrates that the placement of arrays of mm-scale vortex generators near the edges of the leaflets diffuses the vortex sheet and suppresses the formation of these vortices, weakening the local velocity gradients and small-scale vortical structures. Supported by NIH and NSF.

  14. Ionization chamber smoke detectors

    International Nuclear Information System (INIS)

    1988-03-01

    One kind of smoke detector, the ionization-type, is regulated by the Atomic Energy Control Board (AECB) because it uses a radioactive substance in its mechanism. Radioactivity and radiation are natural phenomena, but they are not very familiar to the average householder. This has led to a number of questions being asked of the AECB. These questions and AECB responses are outlined

  15. Dung biomass smoke activates inflammatory signaling pathways in human small airway epithelial cells.

    Science.gov (United States)

    McCarthy, Claire E; Duffney, Parker F; Gelein, Robert; Thatcher, Thomas H; Elder, Alison; Phipps, Richard P; Sime, Patricia J

    2016-12-01

    Animal dung is a biomass fuel burned by vulnerable populations who cannot afford cleaner sources of energy, such as wood and gas, for cooking and heating their homes. Exposure to biomass smoke is the leading environmental risk for mortality, with over 4,000,000 deaths each year worldwide attributed to indoor air pollution from biomass smoke. Biomass smoke inhalation is epidemiologically associated with pulmonary diseases, including chronic obstructive pulmonary disease (COPD), lung cancer, and respiratory infections, especially in low and middle-income countries. Yet, few studies have examined the mechanisms of dung biomass smoke-induced inflammatory responses in human lung cells. Here, we tested the hypothesis that dung biomass smoke causes inflammatory responses in human lung cells through signaling pathways involved in acute and chronic lung inflammation. Primary human small airway epithelial cells (SAECs) were exposed to dung smoke at the air-liquid interface using a newly developed, automated, and reproducible dung biomass smoke generation system. The examination of inflammatory signaling showed that dung biomass smoke increased the production of several proinflammatory cytokines and enzymes in SAECs through activation of the activator protein (AP)-1 and arylhydrocarbon receptor (AhR) but not nuclear factor-κB (NF-κB) pathways. We propose that the inflammatory responses of lung cells exposed to dung biomass smoke contribute to the development of respiratory diseases. Copyright © 2016 the American Physiological Society.

  16. Dense framelets with two generators and their application in mechanical fault diagnosis

    Science.gov (United States)

    Qin, Yi; Wang, Jiaxu; Mao, Yongfang

    2013-11-01

    Wavelet analysis has been widely applied to mechanical fault diagnosis. Aiming at the problems of current wavelet basis, such as low time-frequency sampling, asymmetry and poor shift-invariance, this paper develops a new family of dense framelets with two generators and some desirable properties. To perform the corresponding framelet transform, three-channel iterated filterbank should be used, where the first and the third channel is decimated while the second channel is undecimated. This arrangement is very helpful for extracting the fault feature of the mid and low frequency band signal components and obtaining some symmetric framelets. To obtain framelets with high symmetry and a specified number of vanishing moments, B-spline and maximally flat linear FIR filter are, respectively, used to design filterbank. Three symmetric framelets and one framelets with symmetric low-pass filter and high-pass filter are constructed. Compared with the higher density framelets and orthonormal wavelets, the proposed framelets have better shift-invariance and denoising performance. Finally, the proposed framelets are applied to fault diagnosis of two gearboxes. The results show that the proposed framelets can be effectively applied to mechanical fault diagnosis and is superior to other commonly-used framelets/wavelets.

  17. Aerosciences, Aero-Propulsion and Flight Mechanics Technology Development for NASA's Next Generation Launch Technology Program

    Science.gov (United States)

    Cockrell, Charles E., Jr.

    2003-01-01

    The Next Generation Launch Technology (NGLT) program, Vehicle Systems Research and Technology (VSR&T) project is pursuing technology advancements in aerothermodynamics, aeropropulsion and flight mechanics to enable development of future reusable launch vehicle (RLV) systems. The current design trade space includes rocket-propelled, hypersonic airbreathing and hybrid systems in two-stage and single-stage configurations. Aerothermodynamics technologies include experimental and computational databases to evaluate stage separation of two-stage vehicles as well as computational and trajectory simulation tools for this problem. Additionally, advancements in high-fidelity computational tools and measurement techniques are being pursued along with the study of flow physics phenomena, such as boundary-layer transition. Aero-propulsion technology development includes scramjet flowpath development and integration, with a current emphasis on hypervelocity (Mach 10 and above) operation, as well as the study of aero-propulsive interactions and the impact on overall vehicle performance. Flight mechanics technology development is focused on advanced guidance, navigation and control (GN&C) algorithms and adaptive flight control systems for both rocket-propelled and airbreathing vehicles.

  18. Secondhand Smoke

    Science.gov (United States)

    ... clothing, when smokers come back inside, they should wash their hands and change their clothing, especially before holding or hugging children. Never smoke in a car with other people. Even exhaling out the window ...

  19. Measuring environmental emissions from tobacco combustion: Sidestream cigarette smoke literature review

    Science.gov (United States)

    Guerin, M. R.; Higgins, C. E.; Jenkins, R. A.

    The tobacco-derived environmental emission of most common concern is the smoke issuing from cigarettes between puffs. A literature review of smoke formation mechanisms, sampling methods and selected emission factors suggests that sidestream deliveries are actually much less variable than is commonly thought. Examples of devices used to generate and collect sidestream smoke for analysis are described and their advantages and disadvantages discussed. Emissions computed as is common practice from sidestream/mainstream ratios are compared to those determined directly. The ratio method can yield misleading results because of the sensitivity of mainstream deliveries to cigarette and burn characteristics.

  20. The opto-mechanical design for GMOX: a next-generation instrument concept for Gemini

    Science.gov (United States)

    Smee, Stephen A.; Barkhouser, Robert; Robberto, Massimo; Ninkov, Zoran; Gennaro, Mario; Heckman, Timothy M.

    2016-08-01

    We present the opto-mechanical design of GMOX, the Gemini Multi-Object eXtra-wide-band spectrograph, a potential next-generation (Gen-4 #3) facility-class instrument for Gemini. GMOX is a wide-band, multi-object, spectrograph with spectral coverage spanning 350 nm to 2.4 um with a nominal resolving power of R 5000. Through the use of Digital Micromirror Device (DMD) technology, GMOX will be able to acquire spectra from hundreds of sources simultaneously, offering unparalleled flexibility in target selection. Utilizing this technology, GMOX can rapidly adapt individual slits to either seeing-limited or diffraction-limited conditions. The optical design splits the bandpass into three arms, blue, red, and near infrared, with the near-infrared arm being split into three channels covering the Y+J band, H band, and K band. A slit viewing camera in each arm provides imaging capability for target acquisition and fast-feedback for adaptive optics control with either ALTAIR (Gemini North) or GeMS (Gemini South). Mounted at the Cassegrain focus, GMOX is a large (1.3 m x 2.8 m x 2.0 m) complex instrument, with six dichroics, three DMDs (one per arm), five science cameras, and three acquisition cameras. Roughly half of these optics, including one DMD, operate at cryogenic temperature. To maximize stiffness and simplify assembly and alignment, the opto-mechanics are divided into three main sub-assemblies, including a near-infrared cryostat, each having sub-benches to facilitate ease of alignment and testing of the optics. In this paper we present the conceptual opto-mechanical design of GMOX, with an emphasis on the mounting strategy for the optics and the thermal design details related to the near-infrared cryostat.

  1. Mechanism of heat generation from loading gaseous hydrogen isotopes into palladium nanoparticles

    Science.gov (United States)

    Dmitriyeva, Olga

    I have carried out the study of hydrogen isotope reactions in the presence of palladium nanoparticles impregnated into oxide powder. My goal was to explain the mechanisms of heat generation in those systems as a result of exposure to deuterium gas. Some researchers have associated this heating with a nuclear reaction in the Pd lattice. While some earlier experiments showed a correlation between the generation of excess heat and helium production as possible evidence of a nuclear reaction, the results of that research have not been replicated by the other groups and the search for radiation was unsuccessful. Therefore, the unknown origin of the excess heat produced by these systems is of great interest. I synthesized different types of Pd and Pt-impregnated oxide samples similar to those used by other research groups. I used different characterization techniques to confirm that the fabrication method I used is capable of producing Pd nanoparticles on the surface of alumina support. I used a custom built gas-loading system to pressurize the material with hydrogen and deuterium gas while measuring heat output as a result of these pressurizations. My initial study confirmed the excess heat generation in the presence of deuterium. However, the in-situ radiometry and alpha-particle measurements did not show any abnormal increase in counts above the background level. In the absence of nuclear reaction products, I decided to look for a conventional chemical process that could account for the excess heat generation. It was earlier suggested that Pd in its nanoparticle form catalyzes hydrogen/deuterium (H/D) exchange reactions in the material. To prove the chemical nature of the observed phenomena I demonstrated that the reaction can be either exo- or endothermic based on the water isotope trapped in the material and the type of gas provided to the system. The H/D exchange was confirmed by RGA, NMR and FTIR analysis. I quantified the amount of energy that can be released due

  2. A simple distributed mechanism for accounting system self-configuration in next-generation charging and billing

    NARCIS (Netherlands)

    Kühne, R.; Huitema, G.B.; Carle, G.

    2011-01-01

    Modern communication systems are becoming increasingly dynamic and complex. In this article a novel mechanism for next generation charging and billing is presented that enables self-configurability for accounting systems consisting of heterogeneous components. The mechanism is required to be simple,

  3. Second-hand smoke exposure generated by new electronic devices (IQOS® and e-cigs) and traditional cigarettes: submicron particle behaviour in human respiratory system.

    Science.gov (United States)

    Protano, C; Manigrasso, M; Avino, P; Sernia, S; Vitali, M

    2016-01-01

    Passive exposure profiles to submicronic particles (SMPs, 5.6-560 nm) of traditional cigarettes and new electronic commercial devices (e-cig and IQOS®, a new heat-not-burn smoking device) were compared. During smoking, SMPs released by traditional cigarettes resulted four-times higher than those released by electronic and heat-not-burn devices and remained high for at least one hour, while SMPs values returned immediately similar to background for electronic and heat-not-burn devices. In all experiments, approximately half of SMPs resulted so small to reach the alveolar region.

  4. Oscillation mechanics of the respiratory system in never-smoking patients with silicosis: pathophysiological study and evaluation of diagnostic accuracy.

    Science.gov (United States)

    Sá, Paula Morisco de; Lopes, Agnaldo José; Jansen, José Manoel; Melo, Pedro Lopes de

    2013-05-01

    Silicosis is a chronic and incurable occupational disease that can progress even after the cessation of exposure. Recent studies suggest that the forced oscillation technique may help to clarify the changes in lung mechanics resulting from silicosis as well as the detection of these changes. We investigated the effects of airway obstruction in silicosis on respiratory impedance and evaluated the diagnostic efficacy of the forced oscillation technique in these patients. Spirometry was used to classify the airway obstruction, which resulted in four subject categories: controls (n=21), patients with a normal exam (n=12), patients with mild obstruction (n=22), and patients with moderate-to-severe obstruction (n=12). Resistive data were interpreted using the zero-intercept resistance (R0), the resistance at 4 Hz (Rrs4), and the mean resistance. We also analyzed the mean reactance (Xm) and the dynamic compliance. The total mechanical load was evaluated using the absolute value of the respiratory impedance (Z4Hz). The diagnostic potential was evaluated by investigating the area under the receiver operating characteristic curve. ClinicalTrials.gov: NCT01725971. We observed significant (p0.80) and highly accurately in the detection of moderate-to-severe obstruction (area under the curve>0.90). The forced oscillation technique may contribute to the study of the pathophysiology of silicosis and may improve the treatment offered to these patients, thus representing an alternative and/or complementary tool for evaluating respiratory mechanics.

  5. Optical absorption of epoxy resin and its role in the laser ultrasonic generation mechanism in composite materials

    International Nuclear Information System (INIS)

    Stratoudaki, T.; Edwards, C.; Dixon, S.; Palmer, S.B.

    2003-01-01

    Epoxy resins are used in various applications and are essential to the fabrication of carbon fibre reinforced composite materials (CFRCs). This paper investigates laser generated ultrasound in epoxy resins using three different lasers, a TEA CO2, a Nd:YAG and a XeCl excimer. In these partially transparent materials the ultrasonic generation mechanism is directly related to the optical absorption depth which can therefore be measured directly from the ultrasonic waveforms using for example a Michelson interferometer as detector. The present work aims firstly to relate the observed amplitude of the longitudinal wave to the optical absorption depth of the epoxy and secondly to evaluate the role of the epoxy resin to the generation of the ultrasound in CFRCs. For the latter, comparative results of generation efficiency between the three wavelengths are presented and an attempt is made to understand the way that the resin matrix influences the generation mechanism of ultrasound in composite materials

  6. A varying coefficient model to measure the effectiveness of mass media anti-smoking campaigns in generating calls to a Quitline.

    Science.gov (United States)

    Bui, Quang M; Huggins, Richard M; Hwang, Wen-Han; White, Victoria; Erbas, Bircan

    2010-01-01

    Anti-smoking advertisements are an effective population-based smoking reduction strategy. The Quitline telephone service provides a first point of contact for adults considering quitting. Because of data complexity, the relationship between anti-smoking advertising placement, intensity, and time trends in total call volume is poorly understood. In this study we use a recently developed semi-varying coefficient model to elucidate this relationship. Semi-varying coefficient models comprise parametric and nonparametric components. The model is fitted to the daily number of calls to Quitline in Victoria, Australia to estimate a nonparametric long-term trend and parametric terms for day-of-the-week effects and to clarify the relationship with target audience rating points (TARPs) for the Quit and nicotine replacement advertising campaigns. The number of calls to Quitline increased with the TARP value of both the Quit and other smoking cessation advertisement; the TARP values associated with the Quit program were almost twice as effective. The varying coefficient term was statistically significant for peak periods with little or no advertising. Semi-varying coefficient models are useful for modeling public health data when there is little or no information on other factors related to the at-risk population. These models are well suited to modeling call volume to Quitline, because the varying coefficient allowed the underlying time trend to depend on fixed covariates that also vary with time, thereby explaining more of the variation in the call model.

  7. Smoking and periodontal disease.

    Science.gov (United States)

    Zee, K-Y

    2009-09-01

    Periodontal disease is considered to be an opportunistic infection as a result of interactions between the causative agents (dental plaque) and the host responses which may be modulated by genetic, environmental and acquired risk factors. Besides being a well-confirmed risk factor in a number of systemic diseases, tobacco smoking has also been associated with periodontal disease. Over the past 10-15 years, more and more scientific data on the impact of smoking on various aspects of periodontal disease and the underlying mechanisms has been published. The purpose of this review was to provide an overview of the available data in order to give practitioners a better understanding of the relationship between smoking and periodontal disease. Subsequently, they can use some of the information in treatment decisions and give advice to patients who are smokers suffering from periodontal disease.

  8. Smoking and Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Kathleen Chang

    2014-12-01

    Full Text Available Rheumatoid arthritis (RA is a chronic inflammatory disease caused by both genetic and environmental factors. Smoking has been implicated as one of the most important extrinsic risk factors for its development and severity. Recent developments have shed light on the pathophysiology of RA in smokers, including oxidative stress, inflammation, autoantibody formation and epigenetic changes. The association of smoking and the development of RA have been demonstrated through epidemiologic studies, as well as through in vivo and animal models of RA. With increased use of biological agents in addition to standard disease-modifying antirheumatic drugs (DMARDs, there has been interest in how smoking affects drug response in RA treatment. Recent evidence suggests the response and drug survival in people treated with anti-tumour necrosis factor (anti-TNF therapy is poorer in heavy smokers, and possible immunological mechanisms for this effect are presented in the current paper.

  9. Diagnostic examination of Generation 2 lithium-ion cells and assessment ofperformance degradation mechanisms.

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, D. P.; Dees, D. W.; Knuth, J.; Reynolds, E.; Gerald, R.; Hyung,Y.-E.; Belharouak, I.; Stoll, M.; Sammann, E.; MacLaren, S.; Haasch, R.; Twesten,R.; Sardela, M.; Battaglia, V.; Cairns, E.; Kerr, J.; Kerlau, M.; Kostecki, R.; Lei,J.; McCarthy, K.; McLarnon, F.; Reimer, J.; Richardson, T.; Ross, P.; Sloop,S.; Song, X.; Zhuang, V.; Balasubramanian, M.; McBreen, J.; Chung, K.-Y.; Yang, X.Q.; Yoon, W.-S.; Norin, L.

    2005-07-15

    The Advanced Technology Development (ATD) Program is a multilaboratory effort to assist industrial developers of high-power lithium-ion batteries overcome the barriers of cost, calendar life, abuse tolerance, and low-temperature performance so that this technology may be rendered practical for use in hybrid electric vehicles (HEVs). Included in the ATD Program is a comprehensive diagnostics effort conducted by researchers at Argonne National Laboratory (ANL), Brookhaven National Laboratory (BNL), and Lawrence Berkeley National Laboratory (LBNL). The goals of this effort are to identify and characterize processes that limit lithium-ion battery performance and calendar life, and ultimately to describe the specific mechanisms that cause performance degradation. This report is a compilation of the diagnostics effort conducted since spring 2001 to characterize Generation 2 ATD cells and cell components. The report is divided into a main body and appendices. Information on the diagnostic approach, details from individual diagnostic techniques, and details on the phenomenological model used to link the diagnostic data to the loss of 18650-cell electrochemical performance are included in the appendices. The main body of the report includes an overview of the 18650-cell test data, summarizes diagnostic data and modeling information contained in the appendices, and provides an assessment of the various mechanisms that have been postulated to explain performance degradation of the 18650 cells during accelerated aging. This report is intended to serve as a ready reference on ATD Generation 2 18650-cell performance and provide information on the tools for diagnostic examination and relevance of the acquired data. A comprehensive account of our experimental procedures and resulting data may be obtained by consulting the various references listed in the text. We hope that this report will serve as a roadmap for the diagnostic analyses of other lithium-ion technologies being

  10. Evaluate and characterize mechanisms controlling transport, fate and effects of army smokes in an aerosol wind tunnel: Transport, transformations, fate and terrestrial ecological effects of fog oil obscurant smokes: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cataldo, D.A.; Van Voris, P.; Ligotke, M.W.; Fellows, R.J.; McVeety, B.D.; Li, Shu-mei W.; Bolton, H. Jr.; Fredrickson, J.K.

    1989-01-01

    The terrestrial transport, chemical fate, and ecological effects of fog oil (FO) smoke obscurants were evaluated under controlled wind tunnel conditions. The primary objectives of this research program are to characterize and assess the impacts of smoke and obscurants on: (1) natural vegetation characteristic of US Army training sites in the United States; (2) physical and chemical properties of soils representative of these training sites; and (3) soil microbiological and invertebrate communities. Impacts and dose/responses were evaluated based on an exposure scenario, including exposure duration, exposure rate, and sequential cumulative dosing. Key to understanding the environmental impacts of fog oil smoke/obscurants is establishing the importance of environmental parameters, such as relative humidity and wind speed on airborne aerosol characteristics and deposition to receptor surfaces. Direct and indirect biotic effects were evaluated using five plant species and three soil types. 29 refs., 35 figs., 32 tabs.

  11. CRISPR transcript processing: a mechanism for generating a large number of small interfering RNAs

    Directory of Open Access Journals (Sweden)

    Djordjevic Marko

    2012-07-01

    orders of magnitude increase of crRNAs upon cas overexpression. A crucial ingredient of this large increase is fast non-specific degradation by an unspecified nuclease, which suggests that a yet unidentified nuclease(s is a major control element of CRISPR response. Transcriptional regulation may be another important control mechanism, as it can either increase the amount of generated pre-crRNA, or alter the level of cas gene activity. Reviewers This article was reviewed by Mikhail Gelfand, Eugene Koonin and L Aravind.

  12. The ability to generate senescent progeny as a mechanism underlying breast cancer cell heterogeneity.

    Directory of Open Access Journals (Sweden)

    Mine Mumcuoglu

    Full Text Available BACKGROUND: Breast cancer is a remarkably heterogeneous disease. Luminal, basal-like, "normal-like", and ERBB2+ subgroups were identified and were shown to have different prognoses. The mechanisms underlying this heterogeneity are poorly understood. In our study, we explored the role of cellular differentiation and senescence as a potential cause of heterogeneity. METHODOLOGY/PRINCIPAL FINDINGS: A panel of breast cancer cell lines, isogenic clones, and breast tumors were used. Based on their ability to generate senescent progeny under low-density clonogenic conditions, we classified breast cancer cell lines as senescent cell progenitor (SCP and immortal cell progenitor (ICP subtypes. All SCP cell lines expressed estrogen receptor (ER. Loss of ER expression combined with the accumulation of p21(Cip1 correlated with senescence in these cell lines. p21(Cip1 knockdown, estrogen-mediated ER activation or ectopic ER overexpression protected cells against senescence. In contrast, tamoxifen triggered a robust senescence response. As ER expression has been linked to luminal differentiation, we compared the differentiation status of SCP and ICP cell lines using stem/progenitor, luminal, and myoepithelial markers. The SCP cells produced CD24+ or ER+ luminal-like and ASMA+ myoepithelial-like progeny, in addition to CD44+ stem/progenitor-like cells. In contrast, ICP cell lines acted as differentiation-defective stem/progenitor cells. Some ICP cell lines generated only CD44+/CD24-/ER-/ASMA- progenitor/stem-like cells, and others also produced CD24+/ER- luminal-like, but not ASMA+ myoepithelial-like cells. Furthermore, gene expression profiles clustered SCP cell lines with luminal A and "normal-like" tumors, and ICP cell lines with luminal B and basal-like tumors. The ICP cells displayed higher tumorigenicity in immunodeficient mice. CONCLUSIONS/SIGNIFICANCE: Luminal A and "normal-like" breast cancer cell lines were able to generate luminal-like and

  13. CRISPR transcript processing: a mechanism for generating a large number of small interfering RNAs

    Science.gov (United States)

    2012-01-01

    ) increase of crRNAs upon cas overexpression. A crucial ingredient of this large increase is fast non-specific degradation by an unspecified nuclease, which suggests that a yet unidentified nuclease(s) is a major control element of CRISPR response. Transcriptional regulation may be another important control mechanism, as it can either increase the amount of generated pre-crRNA, or alter the level of cas gene activity. Reviewers This article was reviewed by Mikhail Gelfand, Eugene Koonin and L Aravind. PMID:22849651

  14. Peers and adolescent smoking.

    Science.gov (United States)

    Kobus, Kimberly

    2003-05-01

    There is a considerable body of empirical research that has identified adolescent peer relationships as a primary factor involved in adolescent cigarette smoking. Despite this large research base, many questions remain unanswered about the mechanisms by which peers affect youths' smoking behavior. Understanding these processes of influence is key to the development of prevention and intervention programs designed to address adolescent smoking as a significant public health concern. In this paper, theoretical frameworks and empirical findings are reviewed critically which inform the current state of knowledge regarding peer influences on teenage smoking. Specifically, social learning theory, primary socialization theory, social identity theory and social network theory are discussed. Empirical findings regarding peer influence and selection, as well as multiple reference points in adolescent friendships, including best friendships, romantic relationships, peer groups and social crowds, are also reviewed. Review of this work reveals the contribution that peers have in adolescents' use of tobacco, in some cases promoting use, and in other cases deterring it. This review also suggests that peer influences on smoking are more subtle than commonly thought and need to be examined more carefully, including consideration of larger social contexts, e.g. the family, neighborhood, and media. Recommendations for future investigations are made, as well as suggestions for specific methodological approaches that offer promise for advancing our knowledge of the contribution of peers on adolescent tobacco use.

  15. GeMini: The Next-Generation Mechanically-Cooled Germanium Spectrometer

    International Nuclear Information System (INIS)

    Burks, M.

    2008-01-01

    The next-generation mechanically-cooled germanium spectrometer has been developed. GeMini (MINIature GErmanium spectrometer) has been designed to bring high-resolution gamma-ray spectroscopy to a range of demanding field environments. Intended applications include short-notice inspections, border patrol, port monitoring and emergency response, where positive nuclide identification of radioactive materials is required but power and liquid cryogen are not easily available. GeMini weighs 2.75 kg for the basic instrument and 4.5 kg for the full instrument including user interface and ruggedized hermetic packaging. It is very low power allowing it to operate for 10 hours on a single set of rechargeable batteries. This instrument employs technology adapted from the gamma-ray spectrometer currently flying on NASA's Mercury MESSENGER spacecraft. Specifically, infrared shielding techniques allow for a vast reduction of thermal load. This in turn allows for a smaller, lighter-weight design, well-suited for a hand-held instrument. Three working prototypes have been built and tested in the lab. The measured energy resolution is 3 keV fwhm at 662 keV gamma-rays. This paper will focus on the design and performance of the instrument

  16. Anatomy of infrasonic communication in baleen whales: Divergent mechanisms of sound generation in mysticetes and odontocetes

    Science.gov (United States)

    Reidenberg, Joy S.; Laitman, Jeffrey T.

    2004-05-01

    Cetaceans produce sounds at opposite ends of the frequency spectrum. The laryngeal role in odontocete sound production (echolocation, communication) remains unclear. Mysticete infrasonics are presumed to be laryngeal in origin, but production mechanisms are unknown. To address this, we examined postmortem larynges in 6 mysticete species (3 genera) and compared them to our odontocete collection (20 species/15 genera). Results indicate that the rostral portion of the odontocete larynx is elongated, narrow, rigid, and normally positioned intranarially. This portion of the mysticete larynx is comparatively shortened, open, pliable, and in Megaptera may be retracted from its intranarial position. Internally, mysticete vocal folds are thick, paired, and oriented horizontally, compared with the thin, usually unpaired, and vertically oriented odontocete fold. Mysticetes may generate low frequency sounds via pneumatically driven fold vibrations, which then pass to attached laryngeal sac walls, through overlying throat pleats, to water. Rorqual mysticetes may also vibrate paired corniculate flaps while regulating airflow into the nasal region. Infrasonic pulses may pass through adjacent soft palate, skull, or nasal cartilages to water. Laryngeal anatomy in mysticetes and odontocetes appears highly divergent. These morphological differences may correlate to adaptations for producing infrasonic (mysticete) or ultrasonic (odontocete) communication. [Work supported by ONR:N00014-96-1-0764, ONR:N00014-99-1-0815, and AMNHSOF.

  17. Hybrid scheduling mechanisms for Next-generation Passive Optical Networks based on network coding

    Science.gov (United States)

    Zhao, Jijun; Bai, Wei; Liu, Xin; Feng, Nan; Maier, Martin

    2014-10-01

    Network coding (NC) integrated into Passive Optical Networks (PONs) is regarded as a promising solution to achieve higher throughput and energy efficiency. To efficiently support multimedia traffic under this new transmission mode, novel NC-based hybrid scheduling mechanisms for Next-generation PONs (NG-PONs) including energy management, time slot management, resource allocation, and Quality-of-Service (QoS) scheduling are proposed in this paper. First, we design an energy-saving scheme that is based on Bidirectional Centric Scheduling (BCS) to reduce the energy consumption of both the Optical Line Terminal (OLT) and Optical Network Units (ONUs). Next, we propose an intra-ONU scheduling and an inter-ONU scheduling scheme, which takes NC into account to support service differentiation and QoS assurance. The presented simulation results show that BCS achieves higher energy efficiency under low traffic loads, clearly outperforming the alternative NC-based Upstream Centric Scheduling (UCS) scheme. Furthermore, BCS is shown to provide better QoS assurance.

  18. Generation mechanism of nonlinear ultrasonic Lamb waves in thin plates with randomly distributed micro-cracks.

    Science.gov (United States)

    Zhao, Youxuan; Li, Feilong; Cao, Peng; Liu, Yaolu; Zhang, Jianyu; Fu, Shaoyun; Zhang, Jun; Hu, Ning

    2017-08-01

    Since the identification of micro-cracks in engineering materials is very valuable in understanding the initial and slight changes in mechanical properties of materials under complex working environments, numerical simulations on the propagation of the low frequency S 0 Lamb wave in thin plates with randomly distributed micro-cracks were performed to study the behavior of nonlinear Lamb waves. The results showed that while the influence of the randomly distributed micro-cracks on the phase velocity of the low frequency S 0 fundamental waves could be neglected, significant ultrasonic nonlinear effects caused by the randomly distributed micro-cracks was discovered, which mainly presented as a second harmonic generation. By using a Monte Carlo simulation method, we found that the acoustic nonlinear parameter increased linearly with the micro-crack density and the size of micro-crack zone, and it was also related to the excitation frequency and friction coefficient of the micro-crack surfaces. In addition, it was found that the nonlinear effect of waves reflected by the micro-cracks was more noticeable than that of the transmitted waves. This study theoretically reveals that the low frequency S 0 mode of Lamb waves can be used as the fundamental waves to quantitatively identify micro-cracks in thin plates. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. GeMini: The Next-Generation Mechanically-Cooled Germanium Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Burks, M

    2008-11-12

    The next-generation mechanically-cooled germanium spectrometer has been developed. GeMini (MINIature GErmanium spectrometer) has been designed to bring high-resolution gamma-ray spectroscopy to a range of demanding field environments. Intended applications include short-notice inspections, border patrol, port monitoring and emergency response, where positive nuclide identification of radioactive materials is required but power and liquid cryogen are not easily available. GeMini weighs 2.75 kg for the basic instrument and 4.5 kg for the full instrument including user interface and ruggedized hermetic packaging. It is very low power allowing it to operate for 10 hours on a single set of rechargeable batteries. This instrument employs technology adapted from the gamma-ray spectrometer currently flying on NASA's Mercury MESSENGER spacecraft. Specifically, infrared shielding techniques allow for a vast reduction of thermal load. This in turn allows for a smaller, lighter-weight design, well-suited for a hand-held instrument. Three working prototypes have been built and tested in the lab. The measured energy resolution is 3 keV fwhm at 662 keV gamma-rays. This paper will focus on the design and performance of the instrument.

  20. Combining mechanical foaming and thermally induced phase separation to generate chitosan scaffolds for soft tissue engineering.

    Science.gov (United States)

    Biswas, D P; Tran, P A; Tallon, C; O'Connor, A J

    2017-02-01

    In this paper, a novel foaming methodology consisting of turbulent mixing and thermally induced phase separation (TIPS) was used to generate scaffolds for tissue engineering. Air bubbles were mechanically introduced into a chitosan solution which forms the continuous polymer/liquid phase in the foam created. The air bubbles entrained in the foam act as a template for the macroporous architecture of the final scaffolds. Wet foams were crosslinked via glutaraldehyde and frozen at -20 °C to induce TIPS in order to limit film drainage, bubble coalescence and Ostwald ripening. The effects of production parameters, including mixing speed, surfactant concentration and chitosan concentration, on foaming are explored. Using this method, hydrogel scaffolds were successfully produced with up to 80% porosity, average pore sizes of 120 μm and readily tuneable compressive modulus in the range of 2.6 to 25 kPa relevant to soft tissue engineering applications. These scaffolds supported 3T3 fibroblast cell proliferation and penetration and therefore show significant potential for application in soft tissue engineering.

  1. Carter constant induced mechanism for generation of anisotropic kinetic equilibria in collisionless N-body systems

    Science.gov (United States)

    Cremaschini, Claudio; Stuchlík, Zdeněk

    A new intrinsically-relativistic kinetic mechanism for generation of nonisotropic relativistic kinetic equilibria in collisionless N-body systems is pointed out. The theory is developed in the framework of the covariant Vlasov statistical description. The new effect is based on the constraints placed by the conservation laws of neutral single-particle dynamics in prescribed background curved-spacetimes demonstrating existence of Killing tensors. As an illustration, the particular case of the Kerr spacetime admitting the so-called Carter constant for the particle geodesic motion is considered. The general functional form of the equilibrium kinetic distribution function (KDF) is determined and an explicit realization in terms of Gaussian-like distributions is provided. It is shown that, due to the Carter constant, these equilibrium KDFs exhibit an anisotropic phase-space functional dependence in terms of the single-particle 4-velocity components, giving rise to corresponding nonisotropic continuum fluid fields. The qualitative properties of the equilibrium stress-energy tensor associated with these systems are discussed, with a particular emphasis on the related occurrence of temperature anisotropy effects. The theory is susceptible of astrophysical applications, including in particular the statistical properties of dark matter (DM) halos around stellar-mass or galactic-center black holes.

  2. Economic evaluation of maintenance strategies for steam generator tubes using probabilistic fracture mechanics and financial method

    International Nuclear Information System (INIS)

    Sagisaka, Mitsuyuki; Isobe, Yoshihiro; Yoshimura, Shinobu; Yagawa, Genki

    2004-01-01

    As an application of probabilistic fracture mechanics (PFM) and a financial method, risk-benefit analyses were performed for the purpose of optimizing maintenance activities of steam generator (SG) tubes used in pressurized water reactors (PWRs). Parameters such as in-service inspection (ISI) detection accuracy, ISI interval, sampling inspection, replacement of SGs and stress corrosion cracking (SCC) allowance operation were selected for sensitivity analyses. In the analysis of the operation introducing maintenance criteria, the effect of quantitative accuracy of the inspection was also taken into account. Although the analyses were mainly conducted for SG tubes made of Inconel 600 mill anneal (MA) materials, the analyses were also performed for SCC-resistant materials with making assumptions on their crack initiation probabilities and crack propagation laws. To justify whether or not it is worth while implementing the selected maintenance strategies in terms of an economic point of view, net present value (NPV) was calculated as an index which is one of the most fundamental financial indices for decision-making based on the discounted cash flow (DCF) method. (author)

  3. Benefits of integrating chemical and mechanical cleaning processes for steam generator sludge removal

    International Nuclear Information System (INIS)

    Varrin, R.D.; Ferriter, A.M.; Oliver, T.W.; Le Surf, J.E.

    1992-01-01

    This paper discusses the benefits of performing in-bundle tubesheet lancing in conjunction with chemical cleaning of PWR and PHWR steam generators in which a hard sludge pile is known to exist. The primary benefits of in-bundle lancing are to: (1) increase the exposed area of the sludge pile by cutting furrows in the surface thereby enhancing dissolution of sludge, (2) reduce the volume of solvents required since material removed by lancing does not have to be dissolved chemically, (3) improve rinsing and removal of residual solvent between iron and copper dissolution steps, and (4) allow for verification of process effectiveness by providing high quality in-bundle visual inspection. The reduction in solvent volumes can lead to a significant reduction in solvent costs and waste processing. A case study which includes an economic evaluation for a combined chemical and mechanical cleaning shows a potential cost saving of up to US$ 300,000 over use of chemical cleaning alone. 14 refs., 2 tabs., 2 figs

  4. Influence of smoking parameters on the concentration of polycyclic aromatic hydrocarbons (PAHs) in Danish smoked fish

    DEFF Research Database (Denmark)

    Duedahl-Olesen, Lene; Christensen, J. H.; Højgård, A.

    2010-01-01

    were also tested in a pilot plant study with smoked trout as a model fish. In addition to confirming that increased combustion temperatures and usage of common alder in comparison with beech increased Sigma PAH25, it was also revealed that the PAH concentration decreased in the order fish skin >> outer...... smoking, and for other fish species direct smoking leads to higher sigma PAH25 than indirect smoking. Also, the usage of common alder increases the PAH contamination compared with beech. The effects of smoking time, combustion temperatures, and two types of smoke-generating material on the Sigma PAH25...

  5. Quantum Mechanical Energy-based Screening of Combinatorially Generated Library of Tautomers. TauTGen. A Tautomer Generator Program

    Energy Technology Data Exchange (ETDEWEB)

    Haranczyk, Maciej; Gutowski, Maciej S

    2007-03-01

    Many computational methods have been derived from quantum mechanics for molecular and extended systems. We advocate that these methods will soon become indispensable research tools of combinatorial chemistry. Although applications of these combinatorial methods driven by quantum-mechanics-derived computational engines seem to be distant, our recent experience suggests the opposite. We developed algorithms and codes to search for the most stable tautomers of molecules. In our approach, we: (i) create large libraries of molecular tautomers using combinatorial methods, and (ii) prescreen these libraries using quantum chemical electronic structure methods. We have identified many adiabatically bound and previously unknown tautomers of anionic nucleic acid bases. Our results unraveled that ordering of nucleic acid bases according to their affinity to an excess electron is: G > U > T > C > A , when all biologically relevant tautomers are considered. Acknowledgements This work was supported by the: (i) US DOE Office of Biological and Environmental Research, Low Dose Radiation Research Program (M.G.) and (ii) Polish State Committee for Scientific Research (KBN) Grant DS/8221-4-0140-4 (M.H.). M.H. thanks for financial support from the European Union Social Funds ZPORR/2.22/II/2.6/ARP/U/2/O5. M.H. is a holder of the award from the Fundation for Polish Science (FNP). R.A.B. acknowledges the financial support from Nanoquant EC Marie Curie Research Training Network, contract number: MRTN-506842. Computing resources were available through: (i) the Academic Computer Center in Gdansk (TASK) (ii) a Computational Grand Challenge Application grant from the Molecular Sciences Computing Facility (MSCF) in the Environmental Molecular Sciences Laboratory located at the Pacific Northwest National Laboratory, and (iii) the National Energy Research Scientific Computing Center (NERSC). The MSCF is funded by DOE’s Office of Biological and Environmental Research. PNNL is operated by Battelle

  6. Smoke detectors

    International Nuclear Information System (INIS)

    Bryant, J.

    1979-01-01

    An ionization smoke detector consisting of two electrodes defining an ionization chamber permitting entry of smoke, a radioactive source to ionize gas in the chamber and a potential difference applied across the first and second electrodes to cause an ion current to flow is described. The current is affected by entry of smoke. An auxiliary electrode is positioned in the ionization chamber between the first and second electrodes, and it is arranged to maintain or create a potential difference between the first electrode and the auxiliary electrode. The auxiliary electrode may be used for testing or for adjustment of sensitivity. A collector electrode divides the chamber into two regions with the auxiliary electrode in the outer sensing region. (U.K.)

  7. Smoke Mask

    Science.gov (United States)

    2003-01-01

    Smoke inhalation injury from the noxious products of fire combustion accounts for as much as 80 percent of fire-related deaths in the United States. Many of these deaths are preventable. Smoke Mask, Inc. (SMI), of Myrtle Beach, South Carolina, is working to decrease these casualties with its line of life safety devices. The SMI personal escape hood and the Guardian Filtration System provide respiratory protection that enables people to escape from hazardous and unsafe conditions. The breathing filter technology utilized in the products is specifically designed to supply breathable air for 20 minutes. In emergencies, 20 minutes can mean the difference between life and death.

  8. Cigarette Smoking and Sociodemographic, Military, and Health Characteristics of Operation Enduring Freedom and Operation Iraqi Freedom Veterans: 2009-2011 National Health Study for a New Generation of US Veterans.

    Science.gov (United States)

    Cypel, Yasmin S; Hamlett-Berry, Kim; Barth, Shannon K; Christofferson, Dana E; Davey, Victoria J; Eber, Stephanie; Schneiderman, Aaron I; Bossarte, Robert M

    2016-09-01

    We examined the sociodemographic, military, and health characteristics of current cigarette smokers, former smokers, and nonsmokers among Operation Enduring Freedom (OEF) / Operation Iraqi Freedom (OIF) veterans and estimated smoking prevalence to better understand cigarette use in this population. We analyzed data from the US Department of Veterans Affairs (VA) 2009-2011 National Health Study for a New Generation of US Veterans. On the basis of a stratified random sample of 60 000 OEF/OIF veterans, we sought responses to a 72-item questionnaire via mail, telephone, or Internet. Cigarette smoking status was based on self-reported cigarette use in the past year. We used multinomial logistic regression to evaluate associations between smoking status and sociodemographic, military, and health characteristics. Among 19 911 veterans who provided information on cigarette smoking, 5581 were current smokers (weighted percentage: 32.5%, 95% confidence interval [CI]: 31.7-33.2). Current smokers were more likely than nonsmokers or former smokers to be younger, to have less education or income, to be separated/divorced or never married/single, and to have served on active duty or in the army. Comparing current smokers and nonsmokers, some significant associations from adjusted analyses included the following: having a Mental Component Summary score (a measure of overall mental health) above the mean of the US population relative to below the mean (adjusted odds ratio [aOR] = 0.81, 95% CI: 0.73-0.90); having physician-diagnosed depression (aOR = 1.52, 95% CI: 1.33-1.74), respiratory conditions (aOR = 1.16, 95% CI: 1.04-1.30), or repeated seizures/blackouts/convulsions (aOR = 1.80, 95% CI: 1.22-2.67); heavy alcohol use vs never use (aOR = 5.49, 95% CI: 4.57-6.59); a poor vs excellent perception of overall health (aOR = 3.79, 95% CI: 2.60-5.52); and being deployed vs nondeployed (aOR = 0.87, 95% CI: 0.78-0.96). Using health care services from the VA protected against current

  9. A 12-month, randomized, controlled study to evaluate exposure and cardiovascular risk factors in adult smokers switching from conventional cigarettes to a second-generation electrically heated cigarette smoking system.

    Science.gov (United States)

    Roethig, Hans J; Feng, Shixia; Liang, Qiwei; Liu, Jianmin; Rees, William A; Zedler, Barbara K

    2008-05-01

    This randomized, controlled, forced-switching, open-label, parallel-group study in 97 adult male and female smokers of conventional cigarettes evaluated biomarkers of tobacco smoke exposure and cardiovascular risk factors. After baseline measurements, smokers were either switched to a second-generation electrically heated cigarette smoking system (EHCSS) or continued smoking conventional cigarettes for 12 months. Biomarkers of exposure and cardiovascular risk factors were measured at 0.5, 1, 2, 3, 4, 5, 6, 9, and 12 months. There was a rapid and sustained reduction in all biomarkers of exposure after switching to the EHCSS, with statistically significant reductions from baseline in nicotine equivalents (-18%), plasma cotinine (-16%), total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (-73%), total 1-hydroxypyrene (-53%), urine mutagenicity (-52%), 4-aminobiphenyl hemoglobin adducts (-43%), carboxyhemoglobin AUC7-23 h (-80%), and 3-hydroxypropylmercapturic acid (-35%). These reductions in exposure in the EHCSS group were associated with statistically significant and pathophysiologically favorable changes in several cardiovascular risk factors, including white blood cell count (-0.78 x 10(3)/microL), hemoglobin (-0.16 g/dL), hematocrit (-0.44%), urine 11-dehydrothromboxane B2 (-374 ng/24 h), and high-density lipoprotein cholesterol (+5 mg/dL).

  10. Mechanically Reconfigurable Single-Arm Spiral Antenna Array for Generation of Broadband Circularly Polarized Orbital Angular Momentum Vortex Waves.

    Science.gov (United States)

    Li, Long; Zhou, Xiaoxiao

    2018-03-23

    In this paper, a mechanically reconfigurable circular array with single-arm spiral antennas (SASAs) is designed, fabricated, and experimentally demonstrated to generate broadband circularly polarized orbital angular momentum (OAM) vortex waves in radio frequency domain. With the symmetrical and broadband properties of single-arm spiral antennas, the vortex waves with different OAM modes can be mechanically reconfigurable generated in a wide band from 3.4 GHz to 4.7 GHz. The prototype of the circular array is proposed, conducted, and fabricated to validate the theoretical analysis. The simulated and experimental results verify that different OAM modes can be effectively generated by rotating the spiral arms of single-arm spiral antennas with corresponding degrees, which greatly simplify the feeding network. The proposed method paves a reconfigurable way to generate multiple OAM vortex waves with spin angular momentum (SAM) in radio and microwave satellite communication applications.

  11. Attractive Noncovalent Interactions in the Mechanism of Grubbs Second-Generation Ru Catalysts for Olefin Metathesis.

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yan; Truhlar, Donald G.

    2007-05-10

    Second-generation ruthenium carbenoid catalysts for olefin metathesis are a hundred to a thousand times more active than first-generation catalysts, despite a slower initiation step. A new density functional capable of treating medium-range correlation energy shows that the relative rates of generation of the catalyst are determined by attractive noncovalent interactions.

  12. Frictional melt generated by the 2008 Mw 7.9 Wenchuan earthquake and its faulting mechanisms

    Science.gov (United States)

    Wang, H.; Li, H.; Si, J.; Sun, Z.; Zhang, L.; He, X.

    2017-12-01

    Fault-related pseudotachylytes are considered as fossil earthquakes, conveying significant information that provide improved insight into fault behaviors and their mechanical properties. The WFSD project was carried out right after the 2008 Wenchuan earthquake, detailed research was conducted in the drilling cores. 2 mm rigid black layer with fresh slickenlines was observed at 732.6 m in WFSD-1 cores drilled at the southern Yingxiu-Beichuan fault (YBF). Evidence of optical microscopy, FESEM and FIB-TEM show it's frictional melt (pseudotachylyte). In the northern part of YBF, 4 mm fresh melt was found at 1084 m with similar structures in WFSD-4S cores. The melts contain numerous microcracks. Considering that (1) the highly unstable property of the frictional melt (easily be altered or devitrified) under geological conditions; (2) the unfilled microcracks; (3) fresh slickenlines and (4) recent large earthquake in this area, we believe that 2-4 mm melt was produced by the 2008 Wenchuan earthquake. This is the first report of fresh pseudotachylyte with slickenlines in natural fault that generated by modern earthquake. Geochemical analyses show that fault rocks at 732.6 m are enriched in CaO, Fe2O3, FeO, H2O+ and LOI, whereas depleted in SiO2. XRF results show that Ca and Fe are enriched obviously in the 2.5 cm fine-grained fault rocks and Ba enriched in the slip surface. The melt has a higher magnetic susceptibility value, which may due to neoformed magnetite and metallic iron formed in fault frictional melt. Frictional melt visible in both southern and northern part of YBF reveals that frictional melt lubrication played a major role in the Wenchuan earthquake. Instead of vesicles and microlites, numerous randomly oriented microcracks in the melt, exhibiting a quenching texture. The quenching texture suggests the frictional melt was generated under rapid heat-dissipation condition, implying vigorous fluid circulation during the earthquake. We surmise that during

  13. The Young Generation at UNICEF COP6 ... and other flexibility mechanisms

    International Nuclear Information System (INIS)

    Meskens, Gaston; Avezou, Florence

    2001-01-01

    Climate change and long term energy strategies are world-scale common concerns, and decisions taken now will have an important impact on the quality of life of our future generations. As electricity production is one of the major CO 2 sources (next to transport and domestic use of energy), nuclear can play a role when it comes to agree on policies and measures to cut global warming - even with regard to sensitive topics such as joint implementation, clean development mechanisms and trading. The Sixth Conference of the Parties (COP6) on the UN Framework Convention on Climate Change met in The Hague (Netherlands) on November 13-24, 2000. It was expected that the final details on the implementation of the Kyoto Protocol would be determined during this conference, so that developed countries can start the process of ratification of the accords. It turned out different. For the nuclear industry, there is optimism. The conference was a success because no agreement is better than exclusion. The industry received a lot of attention, that was more negative than positive, but still, it is open for discussion. COP6 was very different from the previous COP's and SB's. There has never been a bigger difference in perception of nuclear between 'buzz in the corridors' (based on actual positive evolutions in some countries) on the one hand, and references in the official talks on the other hand. This also means that the negotiations are becoming more and more complicated and that a lot of diplomacy is necessary. Given the sensitiveness of the topic, the nuclear representatives decided to keep 'low profile' at COP6. For what the impact of the Young Generation (YG) contacts with the pressure group are concerned, we foresaw COP6 to be the turning point, and we were right. The surprise effect (COP3) is gone, the period of curiosity and 'sympathy' (COP4) and neglect (COP5) is passed and, now that the green groups see that our attendance has an effect, they start to take us seriously

  14. Secondhand Smoke Quiz

    Science.gov (United States)

    ... Ventilation and separate non-smoking sections can eliminate secondhand smoke exposure. True False 8. A healthy non-smoker must ... limit where a person can smoke and reduce secondhand smoke exposure: a) Hurt only small businesses a) Hurt only ...

  15. Smoking and COPD

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000696.htm Smoking and COPD To use the sharing features on ... than if you were to stop smoking. Quit Smoking Quitting smoking is the best thing you can ...

  16. Thermodynamics of a tropical cyclone: generation and dissipation of mechanical energy in a self-driven convection system

    OpenAIRE

    Hisashi Ozawa; Shinya Shimokawa

    2015-01-01

    The formation process of circulatory motion of a tropical cyclone is investigated from a thermodynamic viewpoint. The generation rate of mechanical energy by a fluid motion under diabatic heating and cooling, and the dissipation rate of this energy due to irreversible processes are formulated from the first and second laws of thermodynamics. This formulation is applied to a tropical cyclone, and the formation process of the circulatory motion is examined from a balance between the generation ...

  17. Infinite cloud model of electrification by the precipitation mechanism in the pressence of high rates of ion generation

    International Nuclear Information System (INIS)

    Spangler, J.D.; Rosenkilde, C.E.

    1978-01-01

    We have extended a simple, infinite-cloud, precipitation-mechanism model of thundercloud electrification to include effects due to the presence of radioactive aerosol particles. These effects involve ion generation, currents due to motions of ions and charged aerosol particles, and collection of ions and aerosol particles by hydrometeors and cloud droplets. Our conclusion is that an ion-pair generation rate G equal to or greater than 10 12 m -3 s -1 will prevent significant electric-field growth

  18. The Effect of Five Smoking Cessation Pharmacotherapies on Smoking Cessation Milestones

    Science.gov (United States)

    Japuntich, Sandra J.; Piper, Megan E.; Leventhal, Adam M.; Bolt, Daniel M.; Baker, Timothy B.

    2011-01-01

    Objective: Most smoking cessation studies have used long-term abstinence as their primary outcome measure. Recent research has suggested that long-term abstinence may be an insensitive index of important smoking cessation mechanisms. The goal of the current study was to examine the effects of 5 smoking cessation pharmacotherapies using Shiffman et…

  19. Electrokinetic effect combined with surface-charge assumption: a possible generation mechanism of coseismic EM signals

    Science.gov (United States)

    Ren, Hengxin; Wen, Jian; Huang, Qinghua; Chen, Xiaofei

    2015-02-01

    According to field observations, electromagnetic (EM) signals accompanying seismic waves can be recorded. The orders of magnitude of observed coseismic electric and magnetic signals associated with earthquakes are usually around 1 to 101 mV km-1 and 10-2 to 1 nT, respectively. In this paper, we carry out numerical simulation of coseismic EM signals associated with seismic waves due to electrokinetic effect and compare with field observations. The seismic source is represented by a finite fault measuring 15 × 9 km2 with a max slip displacement 1.5 m, corresponding to a Mw 5.9 earthquake. While using the EM surface boundary condition of continuous horizontal EM components, the magnetic signals only accompany the late-arriving S waves at receiver near the ground surface. This is obviously different from field observations. Thus, we adopt another EM surface boundary condition which assumes the ground surface carries surface charge. For the used half-space model, a surface-charge density magnitude |Qsc| in excess of 10-4 C m-2 is sufficient to make horizontal magnetic components clearly show up at the whole time duration of seismic waves. When |Qsc| increases, the contribution of surface-charge density to coseismic EM signals becomes more and more dominant comparing with that of the seismically induced streaming-current. We estimate the Qsc expected at the Earth's surface might be a value between -5 × 10-4 and -0.1 C m-2 by the comparison between numerical results and field observations. The vertical magnetic signals only accompany the late-arriving seismic waves, because they are theoretically only induced by SH wave. The field observation results of vertical magnetic signals may be resulted from the scattering effect or the seismic dynamo effect. We conclude that electrokinetic effect combined with surface-charge assumption is one possible generation mechanism of the observed coseismic EM signals.

  20. Troxerutin with copper generates oxidative stress in cancer cells: Its possible chemotherapeutic mechanism against hepatocellular carcinoma.

    Science.gov (United States)

    Subastri, Ariraman; Suyavaran, Arumugam; Preedia Babu, Ezhuthupurakkal; Nithyananthan, Subramaniyam; Barathidasan, Rajamani; Thirunavukkarasu, Chinnasamy

    2018-03-01

    Troxerutin (TXER) a rutin derivative is known for its anticancer effect against hepatocellular carcinoma (HCC). As part of large study, recently we have shown TXER interact with genetic material and its anti-mutagenic property. In the present study we have explored its possible mode of action in HCC. Since TXER alone did not show significant anticancer effect on Huh-7 cells, in vitro biochemical assays were performed for determining anticancer efficacy of TXER + metal complex using transition metals such as Cu, Zn, and Fe. The anticancer efficacy of TXER + Cu on Huh-7 cells were evaluated using MTT assay, DCFDA, JC-1 staining, comet assay, cell cycle analysis, immunocytochemistry, and Western blotting. Non-toxic nature of TXER was analyzed on primary rat hepatocytes. The in vivo efficacy of TXER was tested in N-nitrosodiethylamine initiated and γ-benzene hexachloride and partial hepatectomy promoted rat liver cancer. Liver markers, transition metal levels, histopathological examination, and expression levels of GST-P, 8-OHdG and Ki-67 were studied to assess the in vivo anticancer effect of TXER. We observed that TXER + Cu induced extensive cellular death on Huh-7 cells through generating free radicals and did not possess any toxic effect on normal hepatocytes. The in vivo studies revealed that TXER possess significant anti-cancer effect as assessed through improved liver markers and suppressed GST-P, 8-OHdG, and Ki-67 expression. TXER treatment reduced the hepatic Cu level in cancer bearing animals. Current study brings the putative mechanism involved in anti-cancer effect of TXER, further it will help to formulate phytoconstituents coupled anti-cancer drug for effective treatment of HCC. © 2017 Wiley Periodicals, Inc.

  1. Oxidative Stress, Cell Death, and Other Damage to Alveolar Epithelial Cells Induced by Cigarette Smoke

    Directory of Open Access Journals (Sweden)

    Nagai A

    2003-09-01

    Full Text Available Abstract Cigarette smoking is a major risk factor in the development of various lung diseases, including pulmonary emphysema, pulmonary fibrosis, and lung cancer. The mechanisms of these diseases include alterations in alveolar epithelial cells, which are essential in the maintenance of normal alveolar architecture and function. Following cigarette smoking, alterations in alveolar epithelial cells induce an increase in epithelial permeability, a decrease in surfactant production, the inappropriate production of inflammatory cytokines and growth factors, and an increased risk of lung cancer. However, the most deleterious effect of cigarette smoke on alveolar epithelial cells is cell death, i.e., either apoptosis or necrosis depending on the magnitude of cigarette smoke exposure. Cell death induced by cigarette smoke exposure can largely be accounted for by an enhancement in oxidative stress. In fact, cigarette smoke contains and generates many reactive oxygen species that damage alveolar epithelial cells. Whether apoptosis and/or necrosis in alveolar epithelial cells is enhanced in healthy cigarette smokers is presently unclear. However, recent evidence indicates that the apoptosis of alveolar epithelial cells and alveolar endothelial cells is involved in the pathogenesis of pulmonary emphysema, an important cigarette smoke-induced lung disease characterized by the loss of alveolar structures. This review will discuss oxidative stress, cell death, and other damage to alveolar epithelial cells induced by cigarette smoke.

  2. Smoking cessation

    African Journals Online (AJOL)

    It may be worthwhile targeting this population group when developing smoking cessation strategies. Nicotine dependence. Tobacco products contain nicotine, which is the drug that produces dependence in smokers.6. Nicotine affects the dopaminergic system in the brain, causing a sense of well- being, and also increases ...

  3. Smoke detectors

    International Nuclear Information System (INIS)

    Macdonald, E.

    1976-01-01

    A smoke detector is described consisting of a ventilated ionisation chamber having a number of electrodes and containing a radioactive source in the form of a foil supported on the surface of the electrodes. This electrode consists of a plastic material treated with graphite to render it electrically conductive. (U.K.)

  4. The Performance Evaluation of Horizontal Axis Wind Turbine Torque and Mechanical Power Generation Affected by the Number of Blade

    OpenAIRE

    Tan Rodney H. G.; Teow Matthew Y. W.

    2016-01-01

    This paper presents the evaluation of horizontal axis wind turbine torque and mechanical power generation and its relation to the number of blades at a given wind speed. The relationship of wind turbine rotational frequency, tip speed, minimum wind speed, mechanical power and torque related to the number of blades are derived. The purpose of this study is to determine the wind energy extraction efficiency achieved for every increment of blade number. Effective factor is introduced to interpre...

  5. How social media influence college students’ smoking attitudes and intentions

    Science.gov (United States)

    Yoo, Woohyun; Yang, JungHwan; Cho, Eunji

    2016-01-01

    Building on the influence of presumed influence (IPI) model, this study examines how smoking- related messages on social media influence college students’ smoking. We surveyed 366 college students from three U.S. Midwestern universities in 2012 and examined the effects of expression and reception of smoking-related messages on smoking using path analysis. We found that the expression and reception of prosmoking messages not only directly affected smoking but also had indirect effects on smoking through (1) perceived peer expression of prosmoking messages and (2) perceived peer smoking norms. For antismoking messages, only reception had a significant indirect influence on smoking through (1) perceived peer reception of antismoking messages and (2) perceived peer smoking norms. In conclusion, social media function as an effective communication channel for generating, sharing, receiving, and commenting on smoking-related content and are thus influential on college students’ smoking. PMID:27956757

  6. How social media influence college students' smoking attitudes and intentions.

    Science.gov (United States)

    Yoo, Woohyun; Yang, JungHwan; Cho, Eunji

    2016-11-01

    Building on the influence of presumed influence (IPI) model, this study examines how smoking- related messages on social media influence college students' smoking. We surveyed 366 college students from three U.S. Midwestern universities in 2012 and examined the effects of expression and reception of smoking-related messages on smoking using path analysis. We found that the expression and reception of prosmoking messages not only directly affected smoking but also had indirect effects on smoking through (1) perceived peer expression of prosmoking messages and (2) perceived peer smoking norms. For antismoking messages, only reception had a significant indirect influence on smoking through (1) perceived peer reception of antismoking messages and (2) perceived peer smoking norms. In conclusion, social media function as an effective communication channel for generating, sharing, receiving, and commenting on smoking-related content and are thus influential on college students' smoking.

  7. Assessment of Nicotine Exposure From Active Human Cigarette Smoking Time

    Directory of Open Access Journals (Sweden)

    Cahours Xavier

    2017-09-01

    Full Text Available The burning of a cigarette is a series of consecutive sequences of both passive and active burnings when a smoking cycle is applied to the cigarette. A previous study, using a smoking machine, showed that cigarette nicotine yields are dependent linearly on the difference between the time of smouldering (passive burning and the time of smoking (active burning. It is predicted that the smoker’s nicotine yield increases when the intensity of smoking increases, i.e., when the time to smoke a cigarette (smoking time decreases. Note that observations made on machines might not be comparable to human behaviours. The aim of this study was to determine whether nicotine mouth-level exposure could be predicted through measurement of human smoking time. A smoking behaviour study was conducted to compare human smoking nicotine yields obtained from both filter tip analysis and the cigarette burning time model. Results showed that smokers’ exposure to the smoke depends essentially on the speed at which the cigarette is smoked. An increase in human smoking intensity, resulting in a decrease in smoking time, generates an increase in smoke exposure, whatever the puff number, puff duration, puff volume and filter ventilation (open or blocked. The association of a machine smoking yield with a corresponding smoking time, and the time taken by a consumer to smoke the cigarette would provide information on the exposure to smoke constituents in a simple and effective manner.

  8. Smoking During Pregnancy

    Science.gov (United States)

    ... and after they are born. 1,3 Health Effects of Smoking and Secondhand Smoke on Pregnancies Women who smoke have more difficulty ... that can harm unborn babies. 1,2 Health Effects of Smoking and Secondhand Smoke on Babies Mothers who smoke are more likely ...

  9. Lysosomal membrane permeabilization: Carbon nanohorn-induced reactive oxygen species generation and toxicity by this neglected mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Mei, E-mail: happy_deercn@163.com [Nanotube Research Center, National Institute of Advanced Industrial Science and Technology 5-2, 1-1-1 Higashi, Tsukuba 305-8565 (Japan); Zhang, Minfang; Tahara, Yoshio; Chechetka, Svetlana; Miyako, Eijiro [Nanotube Research Center, National Institute of Advanced Industrial Science and Technology 5-2, 1-1-1 Higashi, Tsukuba 305-8565 (Japan); Iijima, Sumio [Nanotube Research Center, National Institute of Advanced Industrial Science and Technology 5-2, 1-1-1 Higashi, Tsukuba 305-8565 (Japan); Faculty of Science and Technology, Meijo University, 1-501 Shiogamaguchi, Tenpaku, Nagoya 468-8502 (Japan); Yudasaka, Masako, E-mail: m-yudasaka@aist.go.jp [Nanotube Research Center, National Institute of Advanced Industrial Science and Technology 5-2, 1-1-1 Higashi, Tsukuba 305-8565 (Japan)

    2014-10-01

    Understanding the molecular mechanisms responsible for the cytotoxic effects of carbon nanomaterials is important for their future biomedical applications. Carbon nanotubular materials induce the generation of reactive oxygen species (ROS), which causes cell death; however, the exact details of this process are still unclear. Here, we identify a mechanism of ROS generation that is involved in the apoptosis of RAW264.7 macrophages caused by excess uptake of carbon nanohorns (CNHs), a typical type of carbon nanotubule. CNH accumulated in the lysosomes, where they induced lysosomal membrane permeabilization (LMP) and the subsequent release of lysosomal proteases, such as cathepsins, which in turn caused mitochondrial dysfunction and triggered the generation of ROS in the mitochondria. The nicotinamide adenine dinucleotide phosphate oxidase was not directly involved in CNH-related ROS production, and the ROS generation cannot be regulated by mitochondrial electron transport chain. ROS fed back to amplify the mitochondrial dysfunction, leading to the subsequent activation of caspases and cell apoptosis. Carbon nanotubules commonly accumulate in the lysosomes after internalization in cells; however, lysosomal dysfunction has not attracted much attention in toxicity studies of these materials. These results suggest that LMP, a neglected mechanism, may be the primary reason for carbon nanotubule toxicity. - Highlights: • We clarify an apoptotic mechanism of RAW264.7 cells caused by carbon nanohorns. • In the meantime, the mechanism of CNH-induced ROS generation is identified. • LMP is the initial factor of CNH-induced ROS generation and cell death. • Cathepsins work as mediators that connect LMP and mitochondrial dysfunction.

  10. The Generation Mechanism of Airy—Bessel Wave Packets in Free Space

    International Nuclear Information System (INIS)

    Ren Zhi-Jun; Ying Chao-Fu; Fan Chang-Jiang; Wu Qiong

    2012-01-01

    Localized optical Airy—Bessel configuration wave packets were first generated on the basis of a grating-telescope combination [Nat. Photon. 4(2010) 103]. By studying the spatially induced group velocity dispersion effect of ultrashort pulsed Bessel beams during propagation, we find the universal physical foundation of generating Airy—Bessel wave packets (ABWs) in free space. The research results are expected to open up more common channels for generating stable linear localized ABWs

  11. Overland flow generation mechanisms affected by topsoil treatment: Application to soil conservation

    Science.gov (United States)

    González Paloma, Hueso; Juan Francisco, Martinez-Murillo; Damian, Ruiz-Sinoga Jose; Hanoch, Lavee

    2015-04-01

    Hortonian overland-flow is responsible for significant amounts of soil loss in Mediterranean geomorphological systems. Restoring the native vegetation is the most effective way to control runoff and sediment yield. During the seeding and plant establishment, vegetation cover may be better sustained if soil is amended with an external source. Four amendments were applied in an experimental set of plots: straw mulching (SM); mulch with chipped branches of Aleppo Pine (Pinus halepensis L.) (PM); TerraCotten hydroabsobent polymers (HP); sewage sludge (RU); and control (C). Plots were afforested following the same spatial pattern, and amendments were mixed with the soil at the rate 10 Mg ha-1. This research demonstrates the role played by the treatments in overland flow generation mechanism (runoff, overland flow and soil moisture along the soil profile). The general overland flow characteristics showed that in the C plots the average overland flow was 8.0 ± 22.0 l per event, and the HP plots produced a similar mean value (8.1 ± 20.1 l). The average overland flow per event was significantly less for soil amended with SM, PM or RU (2.7 ± 8.3 l; 1.3 ± 3.5 l and 2.2 ± 5.9 l, respectively). There was a similar trend with respect to the maximum overland flow. The mean sediment yield per event was relatively high in the C and HP plots (8.6 ± 27.8 kg and 14.8 ± 43.4 kg, respectively), while significantly lower values were registered in the SM, PM and RU plots (0.4 ± 1.0 kg; 0.2 ± 0.3 kg and 0.2 ± 0.3 kg, respectively). Very similar trends were found for the maximum sediment yield. Regarding to the soil moisture values, there was a difference in the trends between the C and HP plots and the SM, PM and RU plots. In the C and HP plots the general trend was for a decrease in soil moisture downward through the soil profile, while in the SM, PM and RU plots the soil moisture remained relatively constant or increased, except for the RU treatment in which the soil moisture

  12. Study on generation mechanisms of second-order nonlinear signals in surface acoustic wave devices and their suppression

    Science.gov (United States)

    Nakagawa, Ryo; Kyoya, Haruki; Shimizu, Hiroshi; Kihara, Takashi; Hashimoto, Ken-ya

    2015-07-01

    In this study, we examine the generation mechanisms of the second-order nonlinear signals in surface acoustic wave resonators/duplexers fabricated on a 42°YX-LiTaO3 substrate. It is shown that the crystal asymmetry of the substrate can generate the second-order nonlinear signals. The following two mechanisms mainly contribute to their generation: (a) self-mixing of the electrostatic field and (b) mixing of the electrostatic field with the strain field associated with laterally propagating modes. Both of them occur at the gaps between the electrode tip and the dummy electrode. In addition, an interdigital transducer design that cancels this asymmetry is proposed. The design is applied to a one-port resonator and a duplexer, and the effectiveness of this technique is demonstrated.

  13. Dissection of the mechanism of manganese porphyrin-catalyzed chlorine dioxide generation.

    Science.gov (United States)

    Umile, Thomas P; Wang, Dong; Groves, John T

    2011-10-17

    Chlorine dioxide, an industrially important biocide and bleach, is produced rapidly and efficiently from chlorite ion in the presence of water-soluble, manganese porphyrins and porphyrazines at neutral pH under mild conditions. The electron-deficient manganese(III) tetra-(N,N-dimethyl)imidazolium porphyrin (MnTDMImP), tetra-(N,N-dimethyl)benzimidazolium (MnTDMBImP) porphyrin, and manganese(III) tetra-N-methyl-2,3-pyridinoporphyrazine (MnTM23PyPz) were found to be the most efficient catalysts for this process. The more typical manganese tetra-4-N-methylpyridiumporphyrin (Mn-4-TMPyP) was much less effective. Rates for the best catalysts were in the range of 0.24-32 TO/s with MnTM23PyPz being the fastest. The kinetics of reactions of the various ClO(x) species (e.g., chlorite ion, hypochlorous acid, and chlorine dioxide) with authentic oxomanganese(IV) and dioxomanganese(V)MnTDMImP intermediates were studied by stopped-flow spectroscopy. Rate-limiting oxidation of the manganese(III) catalyst by chlorite ion via oxygen atom transfer is proposed to afford a trans-dioxomanganese(V) intermediate. Both trans-dioxomanganese(V)TDMImP and oxoaqua-manganese(IV)TDMImP oxidize chlorite ion by 1-electron, generating the product chlorine dioxide with bimolecular rate constants of 6.30 × 10(3) M(-1) s(-1) and 3.13 × 10(3) M(-1) s(-1), respectively, at pH 6.8. Chlorine dioxide was able to oxidize manganese(III)TDMImP to oxomanganese(IV) at a similar rate, establishing a redox steady-state equilibrium under turnover conditions. Hypochlorous acid (HOCl) produced during turnover was found to rapidly and reversibly react with manganese(III)TDMImP to give dioxoMn(V)TDMImP and chloride ion. The measured equilibrium constant for this reaction (K(eq) = 2.2 at pH 5.1) afforded a value for the oxoMn(V)/Mn(III) redox couple under catalytic conditions (E' = 1.35 V vs NHE). In subsequent processes, chlorine dioxide reacts with both oxomanganese(V) and oxomanganese(IV)TDMImP to afford chlorate

  14. Lead generation strategy as a multichannel mechanism of growth of a modern enterprise

    Directory of Open Access Journals (Sweden)

    Łukowski Wojciech

    2016-09-01

    Full Text Available Lead generation strategy describes the marketing process of involvement and capture of interest in a product or service which is aimed at developing sales plans and, as a consequence, soliciting new clients. Lead generation is becoming an increasingly popular demand-generating strategy, which – through its multichannelled dissemination of the generated message – gives it a much greater reach. Lead generation assists organisations in achieving a greater brand awareness, building relationships and attracting more potential clients to fill their sales pipeline. The primary purpose of this publication is identifying the possibilities that the implementation of lead generation strategies provides to modern enterprises. It discusses the key aspects of this issue, demonstrating how the significance of organisations change, how their value effectively increases as a result of the implementation of tools furnished by processes that form an integral part of lead generation. The article defines the factors and processes that affect the effective course of actions undertaken within lead generation campaigns.

  15. A method for generating reduced-order combustion mechanisms that satisfy the differential entropy inequality

    Science.gov (United States)

    Ream, Allen E.; Slattery, John C.; Cizmas, Paul G. A.

    2018-04-01

    This paper presents a new method for determining the Arrhenius parameters of a reduced chemical mechanism such that it satisfies the second law of thermodynamics. The strategy is to approximate the progress of each reaction in the reduced mechanism from the species production rates of a detailed mechanism by using a linear least squares method. A series of non-linear least squares curve fittings are then carried out to find the optimal Arrhenius parameters for each reaction. At this step, the molar rates of production are written such that they comply with a theorem that provides the sufficient conditions for satisfying the second law of thermodynamics. This methodology was used to modify the Arrhenius parameters for the Westbrook and Dryer two-step mechanism and the Peters and Williams three-step mechanism for methane combustion. Both optimized mechanisms showed good agreement with the detailed mechanism for species mole fractions and production rates of most major species. Both optimized mechanisms showed significant improvement over previous mechanisms in minor species production rate prediction. Both optimized mechanisms produced no violations of the second law of thermodynamics.

  16. A Fast Response Mechanism for Insulin Storage in Crystals May Involve a Novel Mode of Kink Generation

    Science.gov (United States)

    Vekilov, Peter

    2010-03-01

    Crystals, likely rhombohedral, of Zn-insulin hexamers form in the islets of Langerhans in the pancreases of many mammals. The suggested function of crystal formation is to protect the insulin from proteases and increase the degree of conversion of soluble proinsulin. To accomplish this, crystal growth should be fast and adaptable to rate fluctuations in the conversion reaction. Zn-insulin crystals grow layer-by-layer. Each layer spreads by the attachment of molecules to kinks located at the layers' edges, also called steps. The kinks are thought to be generated either by thermal fluctuations, as postulated by Gibbs, or by one-dimensional nucleation of new crystalline rows. The kink density determines the rate at which steps advance, and these two kink-generation mechanisms lead to weak near-linear responses of the growth rate to concentration variations. We demonstrate for the crystallization of Zn-insulin a novel mechanism of kink generation, whereby 2D clusters of several insulin molecules pre-formed on the terraces between steps associate to the steps. This mechanism results in several-fold higher kink density, faster rate of crystallization, and a high sensitivity of the kinetics to small increases of the solute concentration. If the found mechanism operates during insulin crystallization in vivo, it could be a part of the biological regulation of insulin production and function. For other crystallizing materials in biological and non-biological systems, this mechanism provides an understanding of the often seen non-linear acceleration of the kinetics.

  17. Mechanical and physical properties of 2 1/4 Cr--1 Mo steel in support of CRBRP steam generator design

    International Nuclear Information System (INIS)

    Brinkman, C.R.; Williams, R.K.; Klueh, R.L.; Hebble, T.L.

    1975-01-01

    Mechanical and physical property tests on annealed 2 1 / 4 Cr-1 Mo steel were conducted in an effort to define behavior in support of the design of the Clinch River Breeder Reactor Plant (CRBRP) steam generator design. Interim empirical expressions and/or data are reported from the results of tensile, creep, fatigue, creep-fatigue, subcritical crack growth, thermal conductivity, thermal diffusivity, and thermal expansion tests and analysis. These expressions cover behavior, where appropriate, over a range of temperatures from 25 to as high as 700 0 C. Comparisons between thermal conductivity and diffusivity values and those found in the American Society of Mechanical Engineers (ASME) Code indicated that the new values were significantly higher than those found presently in the Code. The importance and complexity of obtaining valid mechanical and physical properties for the Clinch River Breeder Reactor Plant (CRBRP) steam generator are discussed. (U.S.)

  18. A Cross-Bridge Cycle with Two Tension-Generating Steps Simulates Skeletal Muscle Mechanics

    Science.gov (United States)

    Offer, Gerald; Ranatunga, K.W.

    2013-01-01

    We examined whether cross-bridge cycle models with one or two tension-generating steps can account for the force-velocity relation of and tension response to length steps of frog skeletal muscle. Transition-state theory defined the strain dependence of the rate constants. The filament stiffness was non-Hookean. Models were refined against experimental data by simulated annealing and downhill simplex runs. Models with one tension-generating step were rejected, as they had a low efficiency and fitted the experimental data relatively poorly. The best model with two tension-generating steps (stroke distances 5.6 and 4.6 nm) and a cross-bridge stiffness of 1.7 pN/nm gave a good account of the experimental data. The two tensing steps allow an efficiency of up to 38% during shortening. In an isometric contraction, 54.7% of the attached heads were in a pre-tension-generating state, 44.5% of the attached heads had undergone the first tension-generating step, and only 0.8% had undergone both tension-generating steps; they bore 34%, 64%, and 2%, respectively, of the isometric tension. During slow shortening, the second tensing step made a greater contribution. During lengthening, up to 93% of the attached heads were in a pre-tension-generating state yet bore elevated tension by being dragged to high strains before detaching. PMID:23972845

  19. Dispositional Mindfulness Predicts Enhanced Smoking Cessation and Smoking Lapse Recovery

    Science.gov (United States)

    Heppner, Whitney L.; Spears, Claire Adams; Correa-Fernández, Virmarie; Castro, Yessenia; Li, Yisheng; Guo, Beibei; Reitzel, Lorraine R.; Vidrine, Jennifer Irvin; Mazas, Carlos A.; Cofta-Woerpel, Ludmila; Cinciripini, Paul M.; Ahluwalia, Jasjit S.; Wetter, David W.

    2016-01-01

    Background Although mindfulness has been hypothesized to promote health behaviors, no research has examined how dispositional mindfulness might influence the process of smoking cessation. Purpose The current study investigated dispositional mindfulness, smoking abstinence, and recovery from a lapse among African American smokers. Methods Participants were 399 African Americans seeking smoking cessation treatment (treatments did not include any components related to mindfulness). Dispositional mindfulness and other psychosocial measures were obtained pre-quit; smoking abstinence was assessed 3 days, 31 days, and 26 weeks post-quit. Results Individuals higher in dispositional mindfulness were more likely to quit smoking both initially and over time. Moreover, among individuals who had lapsed at day 3, those higher in mindfulness were more likely to recover abstinence by the later time points. The mindfulness-early abstinence association was mediated by lower negative affect, lower expectancies to regulate affect via smoking, and higher perceived social support. Conclusions Results suggest that mindfulness might enhance smoking cessation among African American smokers by operating on mechanisms posited by prominent models of addiction. PMID:26743533

  20. Dispositional Mindfulness Predicts Enhanced Smoking Cessation and Smoking Lapse Recovery.

    Science.gov (United States)

    Heppner, Whitney L; Spears, Claire Adams; Correa-Fernández, Virmarie; Castro, Yessenia; Li, Yisheng; Guo, Beibei; Reitzel, Lorraine R; Vidrine, Jennifer Irvin; Mazas, Carlos A; Cofta-Woerpel, Ludmila; Cinciripini, Paul M; Ahluwalia, Jasjit S; Wetter, David W

    2016-06-01

    Although mindfulness has been hypothesized to promote health behaviors, no research has examined how dispositional mindfulness might influence the process of smoking cessation. The current study investigated dispositional mindfulness, smoking abstinence, and recovery from a lapse among African American smokers. Participants were 399 African Americans seeking smoking cessation treatment (treatments did not include any components related to mindfulness). Dispositional mindfulness and other psychosocial measures were obtained pre-quit; smoking abstinence was assessed 3, 31 days, and 26 weeks post-quit. Individuals higher in dispositional mindfulness were more likely to quit smoking both initially and over time. Moreover, among individuals who had lapsed at day 3, those higher in mindfulness were more likely to recover abstinence by the later time points. The mindfulness-early abstinence association was mediated by lower negative affect, lower expectancies to regulate affect via smoking, and higher perceived social support. Results suggest that mindfulness might enhance smoking cessation among African American smokers by operating on mechanisms posited by prominent models of addiction.

  1. Hazardous compounds in tobacco smoke.

    Science.gov (United States)

    Talhout, Reinskje; Schulz, Thomas; Florek, Ewa; van Benthem, Jan; Wester, Piet; Opperhuizen, Antoon

    2011-02-01

    Tobacco smoke is a toxic and carcinogenic mixture of more than 5,000 chemicals. The present article provides a list of 98 hazardous smoke components, based on an extensive literature search for known smoke components and their human health inhalation risks. An electronic database of smoke components containing more than 2,200 entries was generated. Emission levels in mainstream smoke have been found for 542 of the components and a human inhalation risk value for 98 components. As components with potential carcinogenic, cardiovascular and respiratory effects have been included, the three major smoke-related causes of death are all covered by the list. Given that the currently used Hoffmann list of hazardous smoke components is based on data from the 1990s and only includes carcinogens, it is recommended that the current list of 98 hazardous components is used for regulatory purposes instead. To enable risk assessment of components not covered by this list, thresholds of toxicological concern (TTC) have been established from the inhalation risk values found: 0.0018 μg day(-1) for all risks, and 1.2 μg day(-1) for all risks excluding carcinogenicity, the latter being similar to previously reported inhalation TTCs.

  2. Hazardous Compounds in Tobacco Smoke

    Directory of Open Access Journals (Sweden)

    Piet Wester

    2011-02-01

    Full Text Available Tobacco smoke is a toxic and carcinogenic mixture of more than 5,000 chemicals. The present article provides a list of 98 hazardous smoke components, based on an extensive literature search for known smoke components and their human health inhalation risks. An electronic database of smoke components containing more than 2,200 entries was generated. Emission levels in mainstream smoke have been found for 542 of the components and a human inhalation risk value for 98 components. As components with potential carcinogenic, cardiovascular and respiratory effects have been included, the three major smoke-related causes of death are all covered by the list. Given that the currently used Hoffmann list of hazardous smoke components is based on data from the 1990s and only includes carcinogens, it is recommended that the current list of 98 hazardous components is used for regulatory purposes instead. To enable risk assessment of components not covered by this list, thresholds of toxicological concern (TTC have been established from the inhalation risk values found: 0.0018 µg day−1 for all risks, and 1.2 µg day−1 for all risks excluding carcinogenicity, the latter being similar to previously reported inhalation TTCs.

  3. Do Workplace Smoking Bans Reduce Smoking?

    OpenAIRE

    Matthew C. Farrelly; William N. Evans; Edward Montgomery

    1999-01-01

    In recent years there has been a heightened public concern over the potentially harmful effects of environmental tobacco smoke (ETS). In response, smoking has been banned on many jobs. Using data from the 1991 and 1993 National Health Interview Survey and smoking supplements to the September 1992 and May 1993 Current Population Survey, we investigate whether these workplace policies reduce smoking prevalence and smoking intensity among workers. Our estimates suggest that workplace bans reduce...

  4. Hybrid Electro-Mechanical Simulation Tool for Wind Turbine Generators: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Singh, M.; Muljadi, E.; Jonkman, J.

    2013-05-01

    This paper describes the use of MATLAB/Simulink to simulate the electrical and grid-related aspects of a WTG and the FAST aero-elastic wind turbine code to simulate the aerodynamic and mechanical aspects of the WTG. The combination of the two enables studies involving both electrical and mechanical aspects of the WTG.

  5. To create or to recall? Neural mechanisms underlying the generation of creative new ideas☆

    Science.gov (United States)

    Benedek, Mathias; Jauk, Emanuel; Fink, Andreas; Koschutnig, Karl; Reishofer, Gernot; Ebner, Franz; Neubauer, Aljoscha C.

    2014-01-01

    This fMRI study investigated brain activation during creative idea generation using a novel approach allowing spontaneous self-paced generation and expression of ideas. Specifically, we addressed the fundamental question of what brain processes are relevant for the generation of genuinely new creative ideas, in contrast to the mere recollection of old ideas from memory. In general, creative idea generation (i.e., divergent thinking) was associated with extended activations in the left prefrontal cortex and the right medial temporal lobe, and with deactivation of the right temporoparietal junction. The generation of new ideas, as opposed to the retrieval of old ideas, was associated with stronger activation in the left inferior parietal cortex which is known to be involved in mental simulation, imagining, and future thought. Moreover, brain activation in the orbital part of the inferior frontal gyrus was found to increase as a function of the creativity (i.e., originality and appropriateness) of ideas pointing to the role of executive processes for overcoming dominant but uncreative responses. We conclude that the process of idea generation can be generally understood as a state of focused internally-directed attention involving controlled semantic retrieval. Moreover, left inferior parietal cortex and left prefrontal regions may subserve the flexible integration of previous knowledge for the construction of new and creative ideas. PMID:24269573

  6. Health Effects of Hexachloroethane (HC) Smoke

    Science.gov (United States)

    1994-02-08

    chloride, Inhalation, 74_ 07 Toxicity, Toxicology review. 19. ABSTRACT (Continue on revenre i necessary and ientify by block numbr) Grenades, smoke pots...Smoke from Fire Training Devices. The National Institute of Occupational Safety and Health (NIOSH) conducted experiments with several HC smoke generating... camphor - like odor. It has a high vapor pressure which allows for a maximum air concentration of about 770 ppm at 25*C. Because of this volatility, it

  7. Vaccines to combat smoking.

    Science.gov (United States)

    Bevins, Rick A; Wilkinson, Jamie L; Sanderson, Sam D

    2008-04-01

    Current US FDA-approved biological therapies for treating smoking target central nervous system processes. Although these therapies have had some success, relapse within a year is still high. Clearly additional strategies are needed to aid individuals in maintaining abstinence. We briefly discuss promising research using vaccines to combat smoking and then identify some potentially important directions for future research. Immunization with a nicotine vaccine generates drug-specific antibodies that sequester some of the nicotine in the peripheral circulation preventing it from entering the brain, thus decreasing its addictive effects. Albeit promising, much more research is necessary to identify more efficacious vaccine designs and formulations, as well as optimal immunization regimens. A further understanding of the factors contributing to the substantial individual differences in immunogenicity to these vaccines and how to best use vaccines in combination with other treatment strategies will increase the success of intervention efforts.

  8. Generation of blue chrysanthemums by anthocyanin B-ring hydroxylation and glucosylation and its coloration mechanism.

    Science.gov (United States)

    Noda, Naonobu; Yoshioka, Satoshi; Kishimoto, Sanae; Nakayama, Masayoshi; Douzono, Mitsuru; Tanaka, Yoshikazu; Aida, Ryutaro

    2017-07-01

    Various colored cultivars of ornamental flowers have been bred by hybridization and mutation breeding; however, the generation of blue flowers for major cut flower plants, such as roses, chrysanthemums, and carnations, has not been achieved by conventional breeding or genetic engineering. Most blue-hued flowers contain delphinidin-based anthocyanins; therefore, delphinidin-producing carnation, rose, and chrysanthemum flowers have been generated by overexpression of the gene encoding flavonoid 3',5'-hydroxylase (F3'5'H), the key enzyme for delphinidin biosynthesis. Even so, the flowers are purple/violet rather than blue. To generate true blue flowers, blue pigments, such as polyacylated anthocyanins and metal complexes, must be introduced by metabolic engineering; however, introducing and controlling multiple transgenes in plants are complicated processes. We succeeded in generating blue chrysanthemum flowers by introduction of butterfly pea UDP (uridine diphosphate)-glucose:anthocyanin 3',5'- O -glucosyltransferase gene, in addition to the expression of the Canterbury bells F3'5'H . Newly synthesized 3',5'-diglucosylated delphinidin-based anthocyanins exhibited a violet color under the weakly acidic pH conditions of flower petal juice and showed a blue color only through intermolecular association, termed "copigmentation," with flavone glucosides in planta. Thus, we achieved the development of blue color by a two-step modification of the anthocyanin structure. This simple method is a promising approach to generate blue flowers in various ornamental plants by metabolic engineering.

  9. Smoking and caffeine consumption: a genetic analysis of their association

    NARCIS (Netherlands)

    Treur, J.L.; Taylor, A.E.; Ware, J.J.; Nivard, M.G.; Neale, M.C.; McMahon, G.; Hottenga, J.J.; Baselmans, B.M.L.; Boomsma, D.I.; Munafò, M.; Vink, J.M.

    2017-01-01

    Smoking and caffeine consumption show a strong positive correlation, but the mechanism underlying this association is unclear. Explanations include shared genetic/environmental factors or causal effects. This study employed three methods to investigate the association between smoking and caffeine.

  10. An agent-based simulation of power generation company behavior in electricity markets under different market-clearing mechanisms

    International Nuclear Information System (INIS)

    Aliabadi, Danial Esmaeili; Kaya, Murat; Şahin, Güvenç

    2017-01-01

    Deregulated electricity markets are expected to provide affordable electricity for consumers through promoting competition. Yet, the results do not always fulfill the expectations. The regulator's market-clearing mechanism is a strategic choice that may affect the level of competition in the market. We conceive of the market-clearing mechanism as composed of two components: pricing rules and rationing policies. We investigate the strategic behavior of power generation companies under different market-clearing mechanisms using an agent-based simulation model which integrates a game-theoretical understanding of the auction mechanism in the electricity market and generation companies' learning mechanism. Results of our simulation experiments are presented using various case studies representing different market settings. The market in simulations is observed to converge to a Nash equilibrium of the stage game or to a similar state under most parameter combinations. Compared to pay-as-bid pricing, bid prices are closer to marginal costs on average under uniform pricing while GenCos' total profit is also higher. The random rationing policy of the ISO turns out to be more successful in achieving lower bid prices and lower GenCo profits. In minimizing GenCos' total profit, a combination of pay-as-bid pricing rule and random rationing policy is observed to be the most promising. - Highlights: • An agent-based simulation of generation company behavior in electricity markets is developed. • Learning dynamics of companies is modeled with an extended Q-learning algorithm. • Different market clearing mechanisms of the regulator are compared. • Convergence to Nash equilibria is analyzed under different cases. • The level of competition in the market is studied.

  11. Effects of exposure to cigarette smoke prior to pregnancy in diabetic rats

    Directory of Open Access Journals (Sweden)

    Damasceno Débora C

    2011-08-01

    Full Text Available Abstract Background The purpose of this study was to evaluate the effects of cigarette smoke exposure before pregnancy on diabetic rats and their offspring development. Methods Diabetes was induced by streptozotocin and cigarette smoke exposure was conducted by mainstream smoke generated by a mechanical smoking device and delivered into a chamber. Diabetic female Wistar rats were randomly distributed in four experimental groups (n minimum = 13/group: nondiabetic (ND and diabetic rats exposed to filtered air (D, diabetic rats exposed to cigarette smoke prior to and into the pregnancy period (DS and diabetic rats exposed to cigarette smoke prior to pregnancy period (DSPP. At day 21 of pregnancy, rats were killed for maternal biochemical determination and reproductive outcomes. Results The association of diabetes and cigarette smoke in DSPP group caused altered glycemia at term, reduced number of implantation and live fetuses, decreased litter and maternal weight, increased pre and postimplantation loss rates, reduced triglyceride and VLDL-c concentrations, increased levels of thiol groups and MDA. Besides, these dams presented increased SOD and GSH-Px activities. However, the increased antioxidant status was not sufficient to prevent the lipid peroxidation observed in these animals. Conclusion Despite the benefits stemming from smoking interruption during the pregnancy of diabetic rats, such improvement was insufficient to avoid metabolic alterations and provide an adequate intrauterine environment for embryofetal development. Therefore, these results suggest that it is necessary to cease smoking extensive time before planning pregnancy, since stopping smoking only when pregnancy is detected may not contribute effectively to fully adequate embryofetal development.

  12. A reforming system for co-generation of hydrogen and mechanical work from methanol

    Science.gov (United States)

    Lyubovsky, Maxim; Walsh, Dennis

    The paper describes a reforming system for converting methanol into pure hydrogen. The system is based on an autothermal reforming reactor operating at elevated pressures followed by membrane-based hydrogen separation. The high-pressure membrane retentate stream is combusted and expanded through a turbine generating additional power. Process simulation illustrates the effects of the system operating parameters on performance and demonstrates system reforming efficiency up to ∼90%. When coupled with a PEM fuel cell and an electrical generator, overall fuel to electricity efficiency can be >48% depending upon the efficiency of a PEM fuel cell stack.

  13. Reforming system for co-generation of hydrogen and mechanical work

    Science.gov (United States)

    Lyubovsky, Maxim; Walsh, Dennis

    The paper describes a new design for a reforming system for converting hydrocarbon fuels into pure hydrogen. The system is based on an autothermal reforming (ATR) reactor operating at elevated pressures followed by membrane-based hydrogen separation. The high-pressure membrane discharge stream is combusted and expanded through a turbine generating additional power. Process simulation modeling illustrates the effect of pressure and other operating parameters on system performance and demonstrates a system reforming efficiency approaching 80%. When coupled with a PEM fuel cell and an electrical generator, fuel to electricity efficiency is above 40%. Other anticipated benefits of the system include compact size, simplicity in control and fast start up.

  14. Native Cellulose Microfiber-Based Hybrid Piezoelectric Generator for Mechanical Energy Harvesting Utility.

    Science.gov (United States)

    Alam, Md Mehebub; Mandal, Dipankar

    2016-01-27

    A flexible hybrid piezoelectric generator (HPG) based on native cellulose microfiber (NCMF) and polydimethylsiloxane (PDMS) with multi wall carbon nanotubes (MWCNTs) as conducting filler is presented where the further chemical treatment of the cellulose and traditional electrical poling steps for piezoelectric voltage generation is avoided. It delivers a high electrical throughput that is an open circuit voltage of ∼30 V and power density ∼9.0 μW/cm(3) under repeated hand punching. We demonstrate to power up various portable electronic units by HPG. Because cellulose is a biocompatible material, suggesting that HPG may have greater potential in biomedical applications such as implantable power source in human body.

  15. Fragmentation of the "bag-breakup" type as a mechanism of the generation of sea spray at strong and hurricane winds

    Science.gov (United States)

    Troitskaya, Yu. I.; Ermakova, O. S.; Kandaurov, A. A.; Kozlov, D. S.; Sergeev, D. A.; Zilitinkevich, S. S.

    2017-11-01

    Experiments on generation mechanisms of sea water spray under hurricane wind were performed using shadow illumination high-speed video recording from several camera positions. Classification of fragmentation mechanism leading to generation of spray was conducted. Statistics of the events causing generation of spray was studied. A phenomenological model was developed based on the methods of statistical physics to describe the "bag-breakup" generation mechanism. The function of spray generation was conducted on this basis, which describes well the experimental data obtained under hurricane winds in the natural and laboratory conditions.

  16. Generation mechanism of hydroxyl radical species and its lifetime prediction during the plasma-initiated ultraviolet (UV) photolysis

    Science.gov (United States)

    Attri, Pankaj; Kim, Yong Hee; Park, Dae Hoon; Park, Ji Hoon; Hong, Young J.; Uhm, Han Sup; Kim, Kyoung-Nam; Fridman, Alexander; Choi, Eun Ha

    2015-03-01

    Through this work, we have elucidated the mechanism of hydroxyl radicals (OH•) generation and its life time measurements in biosolution. We observed that plasma-initiated ultraviolet (UV) photolysis were responsible for the continues generation of OH• species, that resulted in OH• to be major reactive species (RS) in the solution. The density and lifetime of OH• species acted inversely proportional to each other with increasing depth inside the solution. The cause of increased lifetime of OH• inside the solution is predicted using theoretical and semiempirical calculations. Further, to predict the mechanism of conversion of hydroxide ion (OH-) to OH• or H2O2 (hydrogen peroxide) and electron, we determined the current inside the solution of different pH. Additionally, we have investigated the critical criterion for OH• interaction on cancer cell inducing apoptosis under effective OH• exposure time. These studies are innovative in the field of plasma chemistry and medicine.

  17. Identification of the physical mechanism of generation of coherent N2(+) emissions in air by femtosecond laser excitation.

    Science.gov (United States)

    Ni, Jielei; Chu, Wei; Jing, Chenrui; Zhang, Haisu; Zeng, Bin; Yao, Jinping; Li, Guihua; Xie, Hongqiang; Zhang, Chaojin; Xu, Huailiang; Chin, See-Leang; Cheng, Ya; Xu, Zhizhan

    2013-04-08

    Recently, amplification of harmonic-seeded radiation generated through femtosecond laser filamentation in air has been observed, giving rise to coherent emissions at wavelengths corresponding to transitions between different vibrational levels of the electronic B(2)Σ(u)(+) and X(2)Σ(g)(+) states of molecular nitrogen ions [Phys. Rev. A. 84, 051802(R) (2011)]. Here, we carry out systematic investigations on its physical mechanism. Our experimental results do not support the speculation that such excellent coherent emissions could originate from nonlinear optical processes such as four-wave mixing or stimulated Raman scattering, leaving stimulated amplification of harmonic seed due to the population inversion generated in molecular nitrogen ions the most likely mechanism.

  18. Reactor core and passive safety systems descriptions of a next generation pressure tube reactor - mechanical aspects

    Energy Technology Data Exchange (ETDEWEB)

    Yetisir, M.; Gaudet, M.; Rhodes, D.; Hamilton, H.; Pencer, J. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

    2014-07-01

    Canada has been developing a channel-type supercritical water-cooled nuclear reactor concept, often called the Canadian SCWR. The objective of this reactor concept is to meet the technology goals of the Generation IV International Forum (GIF) for the next generation nuclear reactor development, which include enhanced safety features (inherent safe operation and deploying passive safety features), improved resource utilization, sustainable fuel cycle, and greater proliferation resistance than Generation III nuclear reactors. The Canadian SCWR core concept consists of a high-pressure inlet plenum, a separate low-pressure heavy water moderator contained in a calandria vessel, and 336 pressure tubes surrounded by the moderator. The reactor uses supercritical water as a coolant, and a direct steam power cycle to generate electricity. The reactor concept incorporates advanced safety features such as passive core cooling, long-term decay heat rejection to the environment and fuel melt prevention via passive moderator cooling. These features significantly reduce core damage frequency relative to existing nuclear reactors. This paper presents a description of the design concepts for the Canadian SCWR core, reactor building layout and the plant layout. Passive safety concepts are also described that address containment and core cooling following a loss-of coolant accident, as well as long term reactor heat removal at station blackout conditions. (author)

  19. Mechanisms of chemical generation of volatile hydrides for trace element determination (IUPAC Technical Report)

    Czech Academy of Sciences Publication Activity Database

    D'Ulivo, A.; Dědina, Jiří; Mester, Z.; Sturgeon, R. E.; Wang, Q.; Welz, B.

    2011-01-01

    Roč. 83, č. 6 (2011), s. 1283-1340 ISSN 0033-4545 Institutional research plan: CEZ:AV0Z40310501 Keywords : borane complexes * chemical generation of volatile hydrides (CHG) * volatile hydrides Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.789, year: 2011

  20. Effects of smoking in pregnancy on neonatal lung function

    OpenAIRE

    Milner, A.; Marsh, M.; Ingram, D.; Fox, G.; Susiva, C.

    1999-01-01

    AIMS—To assess the effects of smoking during pregnancy on lung mechanics and lung volumes in the immediate neonatal period, before infants are exposed to passive smoking.
METHODS—Lung function tests were carried out within 72 hours of delivery in infants born to 100 non-smoking and 189 smoking mothers. Lung growth was assessed by plethysmography and lung mechanics using the single breath occlusion technique and oesophageal balloon/ pneumotachography. Antenatal maternal serum cotin...

  1. A Robust Method to Generate Mechanically Anisotropic Vascular Smooth Muscle Cell Sheets for Vascular Tissue Engineering.

    Science.gov (United States)

    Backman, Daniel E; LeSavage, Bauer L; Shah, Shivem B; Wong, Joyce Y

    2017-06-01

    In arterial tissue engineering, mimicking native structure and mechanical properties is essential because compliance mismatch can lead to graft failure and further disease. With bottom-up tissue engineering approaches, designing tissue components with proper microscale mechanical properties is crucial to achieve the necessary macroscale properties in the final implant. This study develops a thermoresponsive cell culture platform for growing aligned vascular smooth muscle cell (VSMC) sheets by photografting N-isopropylacrylamide (NIPAAm) onto micropatterned poly(dimethysiloxane) (PDMS). The grafting process is experimentally and computationally optimized to produce PNIPAAm-PDMS substrates optimal for VSMC attachment. To allow long-term VSMC sheet culture and increase the rate of VSMC sheet formation, PNIPAAm-PDMS surfaces were further modified with 3-aminopropyltriethoxysilane yielding a robust, thermoresponsive cell culture platform for culturing VSMC sheets. VSMC cell sheets cultured on patterned thermoresponsive substrates exhibit cellular and collagen alignment in the direction of the micropattern. Mechanical characterization of patterned, single-layer VSMC sheets reveals increased stiffness in the aligned direction compared to the perpendicular direction whereas nonpatterned cell sheets exhibit no directional dependence. Structural and mechanical anisotropy of aligned, single-layer VSMC sheets makes this platform an attractive microstructural building block for engineering a vascular graft to match the in vivo mechanical properties of native arterial tissue. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Thermal analysis experiment for elucidating sodium-water chemical reaction mechanism in steam generator of sodium-cooled fast reactor

    International Nuclear Information System (INIS)

    Kikuchi, Shin; Kurihara, Akikazu; Ohshima, Hiroyuki

    2012-01-01

    For the purpose of elucidating the mechanism of the sodium-water surface reaction in a steam generator of sodium-cooled fast reactors, kinetic study of the sodium (Na)-sodium hydroxide (NaOH) reaction has been carried out by using Differential Thermal Analysis (DTA) technique. The parameters, including melting points of Na and NaOH, phase transition temperature of NaOH, Na-NaOH reaction temperature, and decomposition temperature of sodium hydride (NaH) have been identified from DTA curves. Based on the measured reaction temperature, rate constant of sodium monoxide (Na 2 O) generation was obtained. Thermal analysis results indicated that Na 2 O generation at the secondary overall reaction should be considered during the sodium-water reaction. (author)

  3. MODELING THE ASIAN TSUNAMI EVOLUTION AND PROPAGATION WITH A NEW GENERATION MECHANISM AND A NON-LINEAR DISPERSIVE WAVE MODEL

    Directory of Open Access Journals (Sweden)

    Paul C. Rivera

    2006-01-01

    Full Text Available A common approach in modeling the generation and propagation of tsunami is based on the assumption of a kinematic vertical displacement of ocean water that is analogous to the ocean bottom displacement during a submarine earthquake and the use of a non-dispersive long-wave model to simulate its physical transformation as it radiates outward from the source region. In this study, a new generation mechanism and the use of a highly-dispersive wave model to simulate tsunami inception, propagation and transformation are proposed. The new generation model assumes that transient ground motion during the earthquake can accelerate horizontal currents with opposing directions near the fault line whose successive convergence and divergence generate a series of potentially destructive oceanic waves. The new dynamic model incorporates the effects of earthquake moment magnitude, ocean compressibility through the buoyancy frequency, the effects of focal and water depths, and the orientation of ruptured fault line in the tsunami magnitude and directivity.For tsunami wave simulation, the nonlinear momentum-based wave model includes important wave propagation and transformation mechanisms such as refraction, diffraction, shoaling, partial reflection and transmission, back-scattering, frequency dispersion, and resonant wave-wave interaction. Using this model and a coarse-resolution bathymetry, the new mechanism is tested for the Indian Ocean tsunami of December 26, 2004. A new flooding and drying algorithm that consider waves coming from every direction is also proposed for simulation of inundation of low-lying coastal regions.It is shown in the present study that with the proposed generation model, the observed features of the Asian tsunami such as the initial drying of areas east of the source region and the initial flooding of western coasts are correctly simulated. The formation of a series of tsunami waves with periods and lengths comparable to observations

  4. Cigarette Smoke Disturbs the Survival of CD8+ Tc/Tregs Partially through Muscarinic Receptors-Dependent Mechanisms in Chronic Obstructive Pulmonary Disease.

    Directory of Open Access Journals (Sweden)

    Gang Chen

    Full Text Available CD8+ T cells (Cytotoxic T cells, Tc are known to play a critical role in the pathogenesis of smoking related airway inflammation including chronic obstructive pulmonary disease (COPD. However, how cigarette smoke directly impacts systematic CD8+ T cell and regulatory T cell (Treg subsets, especially by modulating muscarinic acetylcholine receptors (MRs, has yet to be well elucidated.Circulating CD8+ Tc/Tregs in healthy nonsmokers (n = 15, healthy smokers (n = 15 and COPD patients (n = 18 were evaluated by flow cytometry after incubating with anti-CD3, anti-CD8, anti-CD25, anti-Foxp3 antibodies. Peripheral blood T cells (PBT cells from healthy nonsmokers were cultured in the presence of cigarette smoke extract (CSE alone or combined with MRs agonist/antagonist for 5 days. Proliferation and apoptosis were evaluated by flow cytometry using Ki-67/Annexin-V antibodies to measure the effects of CSE on the survival of CD8+ Tc/Tregs.While COPD patients have elevated circulating percentage of CD8+ T cells, healthy smokers have higher frequency of CD8+ Tregs. Elevated percentages of CD8+ T cells correlated inversely with declined FEV1 in COPD. CSE promoted the proliferation and inhibited the apoptosis of CD8+ T cells, while facilitated both the proliferation and apoptosis of CD8+ Tregs. Notably, the effects of CSE on CD8+ Tc/Tregs can be mostly simulated or attenuated by muscarine and atropine, the MR agonist and antagonist, respectively. However, neither muscarine nor atropine influenced the apoptosis of CD8+ Tregs.The results imply that cigarette smoking likely facilitates a proinflammatory state in smokers, which is partially mediated by MR dysfunction. The MR antagonist may be a beneficial drug candidate for cigarette smoke-induced chronic airway inflammation.

  5. Smoking (For Teens)

    Science.gov (United States)

    ... a word, is addiction. Once You Start, It's Hard to Stop Smoking is a hard habit to ... less active than nonsmokers because smoking affects lung power. Smoking can also cause fertility problems and can ...

  6. Smoking Stinks! (For Kids)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Smoking Stinks! KidsHealth / For Kids / Smoking Stinks! What's in ... out more about cigarettes and tobacco. What Are Smoking and Smokeless Tobacco? Tobacco (say: tuh-BA-ko) ...

  7. Smoking and surgery

    Science.gov (United States)

    Surgery - quitting smoking; Surgery - quitting tobacco; Wound healing - smoking ... Tar, nicotine, and other chemicals from smoking can increase your risk of many health problems. These include heart and blood vessel problems, such as: Blood clots and aneurysms in ...

  8. Smoking and Youth

    Science.gov (United States)

    Smoking cigarettes has many health risks for everyone. However, the younger you are when you start smoking, the more problems it can cause. People who start smoking before the age of 21 have the hardest ...

  9. Effects of active and passive tobacco cigarette smoking on heart rate variability.

    Science.gov (United States)

    Dinas, Petros C; Koutedakis, Yiannis; Flouris, Andreas D

    2013-02-20

    Given the widespread incidence of smoking as well as its deleterious health effects, it is crucial to examine practical and cost effective prognostic markers assessing its health impact. Heart rate variability (HRV) is a straightforward and cost effective technique to foresee health problems of cardiovascular nature and may be used to predict in advance smoking-induced health effects. In this review we evaluate the existing biological evidence regarding the effects of smoking on HRV and their associated cardiovascular consequences. In addition, we summarize fundamental information on the various HRV indicators and their diagnostic significance in relation to heart failure. An in depth analysis of the various HRV indices characterizing changes in the activation of the autonomic nervous system is provided together with a critical evaluation of all evidence published to date on the influence of chronic and acute active and passive smoking on HRV. Overall, the vast majority of published evidence suggests that acute and chronic active and passive smoking generate marked disruptions in the normal autonomic nervous system functioning characterized by increased sympathetic drive and reduced HRV and parasympathetic modulation. The proposed mechanisms that may generate this smoke-induced HRV reduction as well as its clinical implications are thoroughly evaluated. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  10. Parental Smoking Exposure and Adolescent Smoking Trajectories

    Science.gov (United States)

    Gilman, Stephen E.; Rende, Richard; Luta, George; Tercyak, Kenneth P.; Niaura, Raymond S.

    2014-01-01

    OBJECTIVE: In a multigenerational study of smoking risk, the objective was to investigate the intergenerational transmission of smoking by examining if exposure to parental smoking and nicotine dependence predicts prospective smoking trajectories among adolescent offspring. METHODS: Adolescents (n = 406) ages 12 to 17 and a parent completed baseline interviews (2001–2004), and adolescents completed up to 2 follow-up interviews 1 and 5 years later. Baseline interviews gathered detailed information on parental smoking history, including timing and duration, current smoking, and nicotine dependence. Adolescent smoking and nicotine dependence were assessed at each time point. Latent Class Growth Analysis identified prospective smoking trajectory classes from adolescence into young adulthood. Logistic regression was used to examine relationships between parental smoking and adolescent smoking trajectories. RESULTS: Four adolescent smoking trajectory classes were identified: early regular smokers (6%), early experimenters (23%), late experimenters (41%), and nonsmokers (30%). Adolescents with parents who were nicotine-dependent smokers at baseline were more likely to be early regular smokers (odds ratio 1.18, 95% confidence interval 1.05–1.33) and early experimenters (odds ratio 1.04, 95% confidence interval 1.04–1.25) with each additional year of previous exposure to parental smoking. Parents’ current non-nicotine–dependent and former smoking were not associated with adolescent smoking trajectories. CONCLUSIONS: Exposure to parental nicotine dependence is a critical factor influencing intergenerational transmission of smoking. Adolescents with nicotine-dependent parents are susceptible to more intense smoking patterns and this risk increases with longer duration of exposure. Research is needed to optimize interventions to help nicotine-dependent parents quit smoking early in their children’s lifetime to reduce these risks. PMID:24819567

  11. Synthesis, Properties, and Mechanism of Action of New Generation of Polycyclic Glycopeptide Antibiotics.

    Science.gov (United States)

    Olsufyeva, Eugenia N; Tevyashova, Anna N

    2017-01-01

    The increased resistance of glycopeptide based antibiotics has become a serious problem for the chemotherapy of infections triggered by resistant Gram-positive bacteria. This has motivated the urgent sincere efforts to develop potent glycopeptide-based antibiotics in both academy and industry research laboratories. Understanding of the mechanism of action of natural and modified glycopeptides is considered as the basis for the rational design of compounds with valuable properties to achieve the fundamental results. Several hydrophobic glycopeptide analogues active against resistant strains were developed during the last two decades. Three drugs, namely, oritavancin, telavancin and dalbavancin were approved by FDA in 2013-2014. It was found that hydrophobic derivatives act through different mechanisms without binding with the modified target of resistant bacteria. Types: Different types of chemical modifications led to several glycopeptide analogues active against Gram-negative bacteria as advocated by in vitro studies or demonstrating potent antiviral activity in the cell models. A new class of glycopeptide antibiotics with potent activity against sensitive and resistant bacterial strains has been recently reported with the aim to overcome the resistance, however, there are a lot of obscure problems in the complete understanding of their mechanisms of actions. In this review, we summarized the achievements of synthetic methods devoted to the construction of new polycyclic glycopeptide antibiotics and described the studies related to their mechanism of actions. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  12. Sociocultural Mechanisms of Intergenerational Values and Mindset Translation in Modern Family Development and Generational Change

    Science.gov (United States)

    Nemova, Olga A.; Retivina, Veronika V.; Kutepova, Lubov I.; Vinnikova, Irina S.; Kuznetsova, Ekaterina A.

    2016-01-01

    The paper considers the issue of functioning of the mechanism of formation and translation of values of labor in family. Fundamental labor values and main channels of their distribution are revealed based on empiric material. Family influence on motivation of today's Russian youth's labor behavior was determined. An intergenerational comparative…

  13. On a mechanism of NPP steam generator cleaning using chelating agents

    International Nuclear Information System (INIS)

    Zverev, V.A.; Margulova, T.Kh.

    1984-01-01

    The experience of steam generator cleaning at the Novovoronezh NPP by means of chelating agents is briefly described. The cleaning process was carried out with the NPP being operative. Examination of surfaces after shutdown shows an essenial decrease in the surface fouling. The heat exchange surface of the steam generator is made of 08Kh18N10T austenitic stainless steel, and the reactor vessel-of pealitic steel. In-operation cleaning in the presence of two different steels consists in hematite removal from the 08Kh18N10T steel with the ferrum chelating agent formation and thermal decomposition of the latter in water and on the vessel pearlitic steel surface with the magnetite layer formation on it

  14. Damage mechanisms and estimation of the frequency of leaks of steam generator tubes in German PWRs

    International Nuclear Information System (INIS)

    Reck, H.

    1992-01-01

    Operating experience of steam generator tubes in German PWRs has shown that so far there have only relatively few cases of damage been registered. The only steam generators with a high failure rate were exchanged in 1983. The material of the affected tubes was Inconel 600. The types of failure that occurred in the late 70's and early 80's were mainly wastage corrosion, which was thought to be the result of phosphate operating. After optimising the water chemistry and changing to ''high AVT'' operating, the failure rate decreased considerably. In total, about 973 of the 193335 tubes that were in operation were plugged because of wall-thinning or leaks. There have been 6 leaks, with the highest leakage volume being 40 liters per hour. 7 refs., 6 figs., 6 tabs

  15. Radiatively Generating the Higgs Potential and Electroweak Scale via the Seesaw Mechanism.

    Science.gov (United States)

    Brivio, Ilaria; Trott, Michael

    2017-10-06

    The minimal seesaw scenario can radiatively generate the Higgs potential to induce electroweak symmetry breaking while supplying an origin of the Higgs vacuum expectation value from an underlying Majorana scale. If the Higgs potential and (derived) electroweak scale have this origin, the heavy SU(3)×SU(2)×U(1)_{Y} singlet states are expected to reside at m_{N}∼10-500  PeV for couplings |ω|∼10^{-4.5}-10^{-6} between the Majorana sector and the standard model. In this framework, the usual challenge of the electroweak scale hierarchy problem with a classically assumed potential is absent as the electroweak scale is not a fundamental scale. The new challenge is the need to generate or accommodate PeV Majorana mass scales while simultaneously suppressing tree-level contributions to the potential in ultraviolet models.

  16. Development of Kinetic Mechanisms for Next-Generation Fuels and CFD Simulation of Advanced Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Pitz, William J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McNenly, Matt J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whitesides, Russell [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mehl, Marco [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Killingsworth, Nick J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Westbrook, Charles K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-12-17

    Predictive chemical kinetic models are needed to represent next-generation fuel components and their mixtures with conventional gasoline and diesel fuels. These kinetic models will allow the prediction of the effect of alternative fuel blends in CFD simulations of advanced spark-ignition and compression-ignition engines. Enabled by kinetic models, CFD simulations can be used to optimize fuel formulations for advanced combustion engines so that maximum engine efficiency, fossil fuel displacement goals, and low pollutant emission goals can be achieved.

  17. Fracture mechanics analysis of the steam generator tube after shot peening

    International Nuclear Information System (INIS)

    Shin, Kyu In; Jhung, Myung Jo; Choi, Young Hwan; Park, Jai Hak

    2003-01-01

    One of the main degradation of steam generator tubes is stress corrosion cracking induced by residual stress. The resulting damages can cause tube bursting or leakage of the primary water which contained radioactivity. Primary water stress corrosion crack occurs at the location of tube/tubesheet hard rolled transition zone. In order to investigate the effect of shot peening on stress corrosion cracking, stress intensity factors are calculated for the crack which is located in the induced residual stress field

  18. CRISPR transcript processing: a mechanism for generating a large number of small interfering RNAs

    OpenAIRE

    Djordjevic Marko; Djordjevic Magdalena; Severinov Konstantin

    2012-01-01

    Abstract Background CRISPR/Cas (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated sequences) is a recently discovered prokaryotic defense system against foreign DNA, including viruses and plasmids. CRISPR cassette is transcribed as a continuous transcript (pre-crRNA), which is processed by Cas proteins into small RNA molecules (crRNAs) that are responsible for defense against invading viruses. Experiments in E. coli report that overexpression of cas genes generates a...

  19. Generation Mechanism of Linear and Angular Ball Velocity in Baseball Pitching

    Directory of Open Access Journals (Sweden)

    Sekiya Koike

    2018-02-01

    Full Text Available The purpose of this study was to quantify the functional roles of the whole-body’s joint torques including fingers’ joints in the generation of ball speed and spin during baseball fast-ball pitching motion. The dynamic contributions of joint torque term, gravitational term, and motion-dependent term (MDT consisting of centrifugal force and Coriolis force, to the generation of the ball variables were calculated using two types of models. Motion and ground reaction forces of a baseball pitcher, who was instructed to throw a fastball into the target, were measured with a motion capture system with two force platforms. The results showed (1 the MDT is the largest contributor to ball speed (e.g., about 31 m/s prior to ball release when using 16-segment model, and (2 the horizontal adduction torque of pitching-side shoulder joint plays a crucial role in generating ball speed with conversion of the MDT into other terms using a recurrence formula.

  20. Generation of sclerosant foams by mechanical methods increases the foam temperature.

    Science.gov (United States)

    Tan, Lulu; Wong, Kaichung; Connor, David; Fakhim, Babak; Behnia, Masud; Parsi, Kurosh

    2017-08-01

    Objective To investigate the effect of agitation on foam temperature. Methods Sodium tetradecyl sulphate and polidocanol were used. Prior to foam generation, the sclerosant and all constituent equipment were cooled to 4-25℃ and compared with cooling the sclerosant only. Foam was generated using a modified Tessari method. During foam agitation, the temperature change was measured using a thermocouple for 120 s. Results Pre-cooling all the constituent equipment resulted in a cooler foam in comparison with only cooling the sclerosant. A starting temperature of 4℃ produced average foam temperatures of 12.5 and 13.2℃ for sodium tetradecyl sulphate and polidocanol, respectively. It was also found that only cooling the liquid sclerosant provided minimal cooling to the final foam temperature, with the temperature 20 and 20.5℃ for sodium tetradecyl sulphate and polidocanol, respectively. Conclusion The foam generation process has a noticeable impact on final foam temperature and needs to be taken into consideration when creating foam.

  1. Evolving Distributed Generation Support Mechanisms: Case Studies from United States, Germany, United Kingdom, and Australia

    Energy Technology Data Exchange (ETDEWEB)

    Lowder, Travis [National Renewable Energy Lab. (NREL), Golden, CO (United States); Zhou, Ella [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tian, Tian [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-03-14

    This report expands on a previous National Renewable Energy Laboratory (NREL) technical report (Lowder et al. 2015) that focused on the United States' unique approach to distributed generation photovoltaics (DGPV) support policies and business models. While the focus of that report was largely historical (i.e., detailing the policies and market developments that led to the growth of DGPV in the United States), this report looks forward, narrating recent changes to laws and regulations as well as the ongoing dialogues over how to incorporate distributed generation (DG) resources onto the electric grid. This report also broadens the scope of Lowder et al. (2015) to include additional countries and technologies. DGPV and storage are the principal technologies under consideration (owing to market readiness and deployment volumes), but the report also contemplates any generation resource that is (1) on the customer side of the meter, (2) used to, at least partly, offset a host's energy consumption, and/or (3) potentially available to provide grid support (e.g., through peak shaving and load shifting, ancillary services, and other means).

  2. Mechanisms Underlying the Immune Response Generated by an Oral Vibrio cholerae Vaccine

    Directory of Open Access Journals (Sweden)

    Danylo Sirskyj

    2016-07-01

    Full Text Available Mechanistic details underlying the resulting protective immune response generated by mucosal vaccines remain largely unknown. We investigated the involvement of Toll-like receptor signaling in the induction of humoral immune responses following oral immunization with Dukoral, comparing wild type mice with TLR-2-, TLR-4-, MyD88- and Trif-deficient mice. Although all groups generated similar levels of IgG antibodies, the proliferation of CD4+ T-cells in response to V. cholerae was shown to be mediated via MyD88/TLR signaling, and independently of Trif signaling. The results demonstrate differential requirements for generation of immune responses. These results also suggest that TLR pathways may be modulators of the quality of immune response elicited by the Dukoral vaccine. Determining the critical signaling pathways involved in the induction of immune response to this vaccine would be beneficial, and could contribute to more precisely-designed versions of other oral vaccines in the future.

  3. Characterization of polymer surface structure and surface mechanical behaviour by sum frequency generation surface vibrational spectroscopy and atomic force microscopy

    International Nuclear Information System (INIS)

    Opdahl, Aric; Koffas, Telly S; Amitay-Sadovsky, Ella; Kim, Joonyeong; Somorjai, Gabor A

    2004-01-01

    Sum frequency generation (SFG) vibrational spectroscopy and atomic force microscopy (AFM) have been used to study polymer surface structure and surface mechanical behaviour, specifically to study the relationships between the surface properties of polymers and their bulk compositions and the environment to which the polymer is exposed. The combination of SFG surface vibrational spectroscopy and AFM has been used to study surface segregation behaviour of polyolefin blends at the polymer/air and polymer/solid interfaces. SFG surface vibrational spectroscopy and AFM experiments have also been performed to characterize the properties of polymer/liquid and polymer/polymer interfaces, focusing on hydrogel materials. A method was developed to study the surface properties of hydrogel contact lens materials at various hydration conditions. Finally, the effect of mechanical stretching on the surface composition and surface mechanical behaviour of phase-separated polyurethanes, used in biomedical implant devices, has been studied by both SFG surface vibrational spectroscopy and AFM. (topical review)

  4. Modifying exposure to smoking depicted in movies: a novel approach to preventing adolescent smoking.

    Science.gov (United States)

    Sargent, James D; Dalton, Madeline A; Heatherton, Todd; Beach, Mike

    2003-07-01

    Most behavioral approaches to adolescent smoking address the behavior directly. We explore an indirect approach: modifying exposure to portrayals of smoking in movies. To describe adolescents' exposure to smoking in movies and to examine factors that could modify such exposure. Occurrences of smoking were counted in each of 601 popular movies. Four thousand nine hundred ten northern New England junior high school students were asked to report which movies they had seen from a randomly generated subsample of 50 films, and responses were used to estimate exposure to the entire sample. Analysis The outcome variable was exposure to movie smoking, defined as the number of smoking occurrences seen. Risk factors for exposure included access to movies (movie channels, videotape use, and movie theater); parenting (R [restricted]-rated movie restrictions, television restrictions, parenting style); and characteristics of the child (age, sex, school performance, sensation-seeking propensity, rebelliousness, and self-esteem). We used multiple regression to assess the association between risk factors and exposure to movie smoking. Subjects had seen an average of 30% of the movie sample (interquartile range, 20%-44%), from which they were exposed to 1160 (interquartile range, 640-1970) occurrences of smoking. In a multivariate model, exposure to movie smoking increased (all P values Parent restriction on viewing R-rated movies resulted in a 50% reduction in exposure to movie smoking. There was no association between parenting style and exposure to movie smoking. Much of the protective effect of parent R-rated movie restriction on adolescent smoking was mediated through lower exposure to movie smoking. Adolescents see thousands of smoking depictions in movies, and this influences their attitudes and behavior. Exposure to movie smoking is reduced when parents limit movie access. Teaching parents to monitor and enforce movie access guidelines could reduce adolescent smoking in an

  5. EFFECTS OF IMPLEMENTATION OF CO-GENERATION IN THE DISTRICT HEATING SYSTEM OF THE FACULTY OF MECHANICAL ENGINEERING IN NIŠ

    Directory of Open Access Journals (Sweden)

    Mladen M Stojiljković

    2010-01-01

    Full Text Available Implementation of co-generation of thermal and electrical energy in district heating systems often results with higher overall energy efficiency of the systems, primary energy savings and environmental benefits. Financial results depend on number of parameters, some of which are very difficult to predict. After introduction of feed-in tariffs for generation of electrical energy in Serbia, better conditions for implementation of co-generation are created, although in district heating systems barriers are still present. In this paper, possibilities and effects of implementation of natural gas fired co-generation engines are examined and presented for the boiler house that is a part of the district heating system owned and operated by the Faculty of Mechanical Engineering in Niš. At the moment, in this boiler house only thermal energy is produced. The boilers are natural gas fired and often operate in low part load regimes. The plant is working only during the heating season. For estimation of effects of implementation of co-generation, referent values are taken from literature or are based on the results of measurements performed on site. Results are presented in the form of primary energy savings and greenhouse gasses emission reduction potentials. Financial aspects are also considered and triangle of costs is shown.

  6. Extracellular histones promote thrombin generation through platelet-dependent mechanisms: involvement of platelet TLR2 and TLR4

    Science.gov (United States)

    Semeraro, Fabrizio; Ammollo, Concetta T.; Morrissey, James H.; Dale, George L.; Friese, Paul; Esmon, Naomi L.

    2011-01-01

    The release of histones from dying cells is associated with microvascular thrombosis and, because histones activate platelets, this could represent a possible pathogenic mechanism. In the present study, we assessed the influence of histones on the procoagulant potential of human platelets in platelet-rich plasma (PRP) and in purified systems. Histones dose-dependently enhanced thrombin generation in PRP in the absence of any trigger, as evaluated by calibrated automated thrombinography regardless of whether the contact phase was inhibited. Activation of coagulation required the presence of fully activatable platelets and was not ascribable to platelet tissue factor, whereas targeting polyphosphate with phosphatase reduced thrombin generation even when factor XII (FXII) was blocked or absent. In the presence of histones, purified polyphosphate was able to induce thrombin generation in plasma independently of FXII. In purified systems, histones induced platelet aggregation; P-selectin, phosphatidylserine, and FV/Va expression; and prothrombinase activity. Blocking platelet TLR2 and TLR4 with mAbs reduced the percentage of activated platelets and lowered the amount of thrombin generated in PRP. These data show that histone-activated platelets possess a procoagulant phenotype that drives plasma thrombin generation and suggest that TLR2 and TLR4 mediate the activation process. PMID:21673343

  7. Smoking cessation medications

    Science.gov (United States)

    Smoking cessation - medications; Smokeless tobacco - medications; Medications for stopping tobacco ... Smoking cessation medicines can: Help with the craving for tobacco. Help you with withdrawal symptoms. Keep you ...

  8. Runoff Generation Mechanisms and Mean Transit Time in a High-Elevation Tropical Ecosystem

    Science.gov (United States)

    Mosquera, G.

    2015-12-01

    Understanding runoff generation processes in tropical mountainous regions remains poorly understood, particularly in ecosystems above the tree line. Here, we provide insights on the process dominating the ecohydrology of the tropical alpine biome (i.e., páramo) of the Zhurucay River Ecohydrological Observatory. The study site is located in south Ecuador between 3400-3900 m in elevation. We used a nested monitoring system with eight catchments (20-753 ha) to measure hydrometric data since December 2010. Biweekly samples of rainfall, streamflow, and soil water at low tension were collected for three years (May 2011-May2014) and analyzed for water stable isotopes. We conducted an isotopic characterization of rainfall, streamflow, and soil waters to investigate runoff generation. These data were also integrated into a lumped model to estimate the mean transit time (MTT) and to investigate landscape features that control its variability. The isotopic characterization evidenced that the water stored in the shallow organic horizon of the Histosol soils (Andean wetlands) located near the streams is the major contributor of water to the streams year-round, whereas the water draining through the hillslope soils, the Andosols, regulates discharge by recharging the wetlands at the valley bottoms. The MTT evaluation indicated relatively short MTTs (0.15-0.73 yr) linked to short subsurface flow paths of water. We also found evidence for topographic controls on the MTT variability. These results reveal that: 1) the ecohydrology of this ecosystem is dominated by shallow subsurface flow in the organic horizon of the soils and 2) the combination of the high storage capacity of the Andean wetlands and the slope of the catchments controls runoff generation and the high water regulation capacity of the ecosystem.

  9. Mechanical design of the hot steam headers of the THTR-300 steam generators

    International Nuclear Information System (INIS)

    Blumer, U.; Stumpf, M.

    1988-01-01

    The high pressure steam headers of the THTR steam generators have been subject to special attention during the design phase due to the following reasons: these components are the pressure retaining parts with the heaviest wall thickness in the region of the steam generators; they therefore are sensitive to thermal transient conditions; they are operated in the elevated temperature regime, where creep effects cannot be neglected; there is almost no service experience from fossil steam generators with this type of material (Alloy 800). Safety consideration therefore have been rather extensive and have focussed on two main areas which will be treated in this paper: 1. Analytical investigations on the cyclic material behaviour under all specified operating conditions, taking into account the non-elastic response of the material. 2. Limitation of the consequences of a header rupture by installation of heavy whip restraints. Elastic-plastic-creep analyses: The analyses were performed in different stages and are explained in the corresponding order: Evaluation of the critical location on the header and establishment of a simplified model of a nozzle region for further analysis. Preliminary thermal analyses of all specified transient conditions on simplified procedures, in order to establish a severity ranking of the conditions. Establishment of representative loading blocks. Evaluation of the material properties for thermal and structural, especially non-elastic behaviour. Detailed thermal analyses. Detailed structural analyses of the non-elastic cyclic response. Extrapolation for all cycles and assessment of the results by design codes. Discussion of the results. Header whip restraint design: In addition to the above analysis efforts, heavy whip restraints were provided to assure limitation of the effects of a header failure. This pager shows the measures that were taken to restrain the movement in case of longitudinal and transverse breaks: The anti-whip designs are

  10. Lead telluride with increased mechanical stability for cylindrical thermoelectric generators; Bleitellurid mit erhoehter mechanischer Stabilitaet fuer zylindrische thermoelektrische Generatoren

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, Andreas

    2013-04-30

    The aim of this work is to improve the mechanical stability of lead telluride (PbTe), trying to vary its mechanical properties independently from its thermoelectric properties. Thus the influence of material preparation as well as different dopants on the mechanical and thermoelectric properties of lead telluride is being analysed. When using appropriately set process parameters, milling and sintering of lead telluride increases the material's hardness. With sintering temperatures exceeding 300 C stable material of high relative density can be achieved. Milling lead telluride generates lattice defects leading to a reduction of the material's charge carrier density. These defects can be reduced by increased sintering temperatures. Contamination of the powder due to the milling process leads to bloating during thermal cycling and thus reduced density of the sintered material. In addition to that, evaporation of tellurium at elevated temperatures causes instability of the material's thermoelectric properties. Based on the experimental results obtained in this work, the best thermoelectric and mechanical properties can be obtained by sintering coarse powders at around 400 C. Within this work a concept was developed to vary the mechanical properties of lead telluride via synthesis of PbTe with electrically nondoping elements, which thus may keep the thermoelectric properties unchanged. Therefore, the mechanical and thermoelectric properties of Pb{sub 1-x}Ca{sub x}Te were investigated. Doping pure PbTe with calcium causes a significant increase of the material's hardness while only slightly decreasing the charge carrier density and thus keeping the thermoelectric properties apart from a slight reduction of the electrical conductivity nearly unchanged. The abovementioned concept is proven using sodium doped lead telluride, as it is used for thermoelectric generators: The additional doping with calcium again increases the material's hardness while

  11. Smoking and women: tragedy of the majority.

    Science.gov (United States)

    Fielding, J E

    1987-11-19

    An increasing number of women are becoming victims of their smoking habit. A broader cross-section of women, other than the very rich and the "indecent," began to smoke in the 1920s, and over the past 50 years tobacco advertising has linked smoking with women's emancipation and achievement of equality with men. The marketing efforts directed to women include special packaging for feminine appeal, "designer" cigarettes, and offering discounted women's products with the purchase of a particular brand of cigarettes. Sponsorship of sporting events coupled with sports themes in cigarette advertisements associates smoking with enhanced physical capacity--a deception. The marketing experts promote smoking as a way of remaining slim in a culture obsessed with thinness. The woman who smokes today is a heavier smoker, on average, with the percentage of women smoking more than 25 cigarettes/day almost doubling from 13% in 1965 to 23% in 1985. Women start smoking at younger and younger ages. 84% of women smokers who are now 28-37 years began to smoke before age 20 as compared with 42% of those now 58-67 years. Today more young women than young men smoke. In addition to the risk of lung cancer, women who smoke also have sex-specific risks, such as those pertaining to a women's reproductive organs and processes. When smoking is of long duration, it appears to increase the risks of intraepithelial neoplasia of the cervix and of invasive cervical cancer. An antiestrogen effect of smoking may provide the explanation for why smoking women reach menopause 1-2 years earlier than nonsmokers. The same mechanism, which has been supported by several case-control studies, may increase postmenopausal osteoporotic fractures, particularly among nonobese women. Possibly the worst consequences of smoking by women are its effects on reproduction and on children. Both a dose-response depressant effect of smoking on fetal development and birth weight have been confirmed. Smoking also reduces

  12. How tobacco smoke causes disease: the biology and behavioral basis for smoking-attributable disease : a report of the Surgeon General

    National Research Council Canada - National Science Library

    2010-01-01

    .... This report specifically reviews the evidence on the potential mechanisms by which smoking causes diseases and considers whether a mechanism is likely to be operative in the production of human disease by tobacco smoke...

  13. Universal smoking installation of rotary type

    Directory of Open Access Journals (Sweden)

    Aminov V. A.

    2017-11-01

    Full Text Available According to the research carried out by the authors the most technological installations for producing meat and fish products are oriented only on one type of raw material (meat or fish, as well as the kind of smoking (cold or hot. Limitations are related to the maximum temperature of the drying agent that affects the product; presence of the system for maintaining the relative humidity of the air mixture; presence of the smoke cooling system coming from the smoke generator and a number of other factors. Enterprises expanding the range of products are forced to purchase new equipment. With a limited production area especially for small businesses this is not convenient. In the paper, a universal smoking installation of the rotor type (USIRT is considered for the production of both meat and fish products using cold or hot smoking. The installation is oriented to a wide range of products. The presence of the smoke cooling system will allow the production of cold smoking products, the presence of the dehumidification and humidification system for the smoke-air mixture will ensure the maintenance of the required technological regime for producing fish and meat products. Based on the example of cold smoking studies have shown that the duration of the process should be reduced while maintaining the quality of the product. For this purpose, ultrasonic (US vibrations have been applied to the smoke-air mixture in USIRT. The studies have been carried out to identify the best type of ultrasound radiators capable of transmitting vibrations of the installation metal surface and from it to pass into the smoke-air mixture in order to intensify the process of cold smoking. The necessary power of ultrasonic generators has been determined. Comparative results of technological processes with the application of ultrasound in the production of fish products have been presented.

  14. Air-coupled acoustic radiation force for non-contact generation of broadband mechanical waves in soft media

    Energy Technology Data Exchange (ETDEWEB)

    Ambroziński, Łukasz [Department of Bioengineering, University of Washington, Seattle, Washington 98195 (United States); AGH University of Science and Technology, Krakow 30059 (Poland); Pelivanov, Ivan, E-mail: ivanp3@uw.edu [Department of Bioengineering, University of Washington, Seattle, Washington 98195 (United States); Faculty of Physics, Moscow State University, Moscow 119991 (Russian Federation); Song, Shaozhen; Yoon, Soon Joon; Gao, Liang; O' Donnell, Matthew [Department of Bioengineering, University of Washington, Seattle, Washington 98195 (United States); Li, David [Department of Bioengineering, University of Washington, Seattle, Washington 98195 (United States); Department of Chemical Engineering, University of Washington Seattle, Washington 98195 (United States); Shen, Tueng T.; Wang, Ruikang K. [Department of Bioengineering, University of Washington, Seattle, Washington 98195 (United States); Department of Ophthalmology, University of Washington, Seattle, Washington 98104 (United States)

    2016-07-25

    A non-contact method for efficient, non-invasive excitation of mechanical waves in soft media is proposed, in which we focus an ultrasound (US) signal through air onto the surface of a medium under study. The US wave reflected from the air/medium interface provides radiation force to the medium surface that launches a transient mechanical wave in the transverse (lateral) direction. The type of mechanical wave is determined by boundary conditions. To prove this concept, a home-made 1 MHz piezo-ceramic transducer with a matching layer to air sends a chirped US signal centered at 1 MHz to a 1.6 mm thick gelatin phantom mimicking soft biological tissue. A phase-sensitive (PhS)-optical coherence tomography system is used to track/image the mechanical wave. The reconstructed transient displacement of the mechanical wave in space and time demonstrates highly efficient generation, thus offering great promise for non-contact, non-invasive characterization of soft media, in general, and for elasticity measurements in delicate soft tissues and organs in bio-medicine, in particular.

  15. Reforming water to generate hydrogen using mechanical alloy; El reformado del agua para generar hidrogeno mediante aleado mecanico

    Energy Technology Data Exchange (ETDEWEB)

    Pena F, D. L.

    2016-07-01

    The objective of this research was to generate a hydrogen production system by means of mechanical milling, in which 0.1 g of magnesium were weighed using a volume of 300 μL for each water solvent (H{sub 2}O) and methanol (CH{sub 3}OH) in a container to start mechanical milling for 2, 4 and 6 h. Once the mechanical milling was finished, the hydrogen that was produced every two hours was measured to determine the appropriate milling time in the production, also in each period of time samples of the powders produced during the milling of Mg were taken, in this process we used characterization techniques such as: X-ray diffraction at an angle of 2θi 5 and 2θf 90 degrees and scanning electron microscopy, taking micrographs of 100, 500, 1000 and 5000 magnifications. According to the mechanical milling results hydrogen was obtained when using water, as well as with methanol. In the techniques of X-ray diffraction characterization different results were obtained before and after the milling, since by the diffractogram s is possible to observe how the magnesium to be put in the mechanical milling along with the water and methanol was diminishing to be transformed into hydroxide and magnesium oxide, as well as in the micrographs taken with scanning electron microscopy the change in the magnesium morphology to hydroxide and magnesium oxide is observed. (Author)

  16. Mechanisms Governing the Creep Behavior of High Temperature Alloys for Generation IV Nuclear Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Vasudevan, Vijay [Univ. of Cincinnati, OH (United States); Carroll, Laura [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sham, Sam [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-04-06

    This research project, which includes collaborators from INL and ORNL, focuses on the study of alloy 617 and alloy 800H that are candidates for applications as intermediate heat exchangers in GEN IV nuclear reactors, with an emphasis on the effects of grain size, grain boundaries and second phases on the creep properties; the mechanisms of dislocation creep, diffusional creep and cavitation; the onset of tertiary creep; and theoretical modeling for long-term predictions of materials behavior and for high temperature alloy design.

  17. Thermodynamics of a tropical cyclone: generation and dissipation of mechanical energy in a self-driven convection system

    Directory of Open Access Journals (Sweden)

    Hisashi Ozawa

    2015-01-01

    Full Text Available The formation process of circulatory motion of a tropical cyclone is investigated from a thermodynamic viewpoint. The generation rate of mechanical energy by a fluid motion under diabatic heating and cooling, and the dissipation rate of this energy due to irreversible processes are formulated from the first and second laws of thermodynamics. This formulation is applied to a tropical cyclone, and the formation process of the circulatory motion is examined from a balance between the generation and dissipation rates of mechanical energy in the fluid system. We find from this formulation and data analysis that the thermodynamic efficiency of tropical cyclones is about 40% lower than the Carnot maximum efficiency because of the presence of thermal dissipation due to irreversible transport of sensible and latent heat in the atmosphere. We show that a tropical cyclone tends to develop within a few days through a feedback supply of mechanical energy when the sea surface temperature is higher than 300 K, and when the horizontal scale of circulation becomes larger than the vertical height of the troposphere. This result is consistent with the critical radius of 50 km and the corresponding central pressure of about 995 hPa found in statistical properties of typhoons observed in the western North Pacific.

  18. Mechanisms of high-frequency song generation in brachypterous crickets and the role of ghost frequencies.

    Science.gov (United States)

    Robillard, Tony; Montealegre-Z, Fernando; Desutter-Grandcolas, Laure; Grandcolas, Philippe; Robert, Daniel

    2013-06-01

    Sound production in crickets relies on stridulation, the well-understood rubbing together of a pair of specialised wings. As the file of one wing slides over the scraper of the other, a series of rhythmic impacts causes harmonic oscillations, usually resulting in the radiation of pure tones delivered at low frequencies (2-8 kHz). In the short-winged crickets of the Lebinthini tribe, acoustic communication relies on signals with remarkably high frequencies (>8 kHz) and rich harmonic content. Using several species of the subfamily Eneopterinae, we characterised the morphological and mechanical specialisations supporting the production of high frequencies, and demonstrated that higher harmonics are exploited as dominant frequencies. These specialisations affect the structure of the stridulatory file, the motor control of stridulation and the resonance of the sound radiator. We placed these specialisations in a phylogenetic framework and show that they serve to exploit high-frequency vibrational modes pre-existing in the phylogenetic ancestor. In Eneopterinae, the lower frequency components are harmonically related to the dominant peak, suggesting they are relicts of ancestral carrier frequencies. Yet, such ghost frequencies still occur in the wings' free resonances, highlighting the fundamental mechanical constraints of sound radiation. These results support the hypothesis that such high-frequency songs evolved stepwise, by a form of punctuated evolution that could be related to functional constraints, rather than by only the progressive increase of the ancestral fundamental frequency.

  19. Diffusion with finite-helicity field tensor: A mechanism of generating heterogeneity

    Science.gov (United States)

    Sato, N.; Yoshida, Z.

    2018-02-01

    Topological constraints on a dynamical system often manifest themselves as breaking of the Hamiltonian structure; well-known examples are nonholonomic constraints on Lagrangian mechanics. The statistical mechanics under such topological constraints is the subject of this study. Conventional arguments based on phase spaces, Jacobi identity, invariant measure, or the H theorem are no longer applicable since all these notions stem from the symplectic geometry underlying canonical Hamiltonian systems. Remembering that Hamiltonian systems are endowed with field tensors (canonical 2-forms) that have zero helicity, our mission is to extend the scope toward the class of systems governed by finite-helicity field tensors. Here, we introduce a class of field tensors that are characterized by Beltrami vectors. We prove an H theorem for this Beltrami class. The most general class of energy-conserving systems are non-Beltrami, for which we identify the "field charge" that prevents the entropy to maximize, resulting in creation of heterogeneous distributions. The essence of the theory can be delineated by classifying three-dimensional dynamics. We then generalize to arbitrary (finite) dimensions.

  20. Thermoelectric generator testing and RTG degradation mechanisms evaluation. Progress report No. 35

    Energy Technology Data Exchange (ETDEWEB)

    Lockwood, A.; Shields, V.

    1980-05-01

    The n-type selenide legs after 14,000 hours continue to show reasonable agreement with the 3M Co. published data. In the ingradient testing after 14,700 hours the n-legs show serious degradation in power to load. Weight loss measurements on the first samples of material produced by G.E. match the results previously obtained on R.C.A. material from the MHW program. The remaining MHW generator on test Q1-A has accumulated 22,519 hours and performance remains stable. The 18 couple modules S/N-1 and -3 previously tested at RCA show no significant change in operation during the current JPL testing. No changes in the trends of degradation of LES 8 and 9 and the Voyager RTGs have been observed.

  1. Program of thermoelectric generator testing and RTG degradation mechanisms evaluation. Progress report No. 38

    Energy Technology Data Exchange (ETDEWEB)

    Lockwood, A.; Shields, V.

    1980-11-01

    The n-type gadolinium selenide legs after 17,500 hours continue to show reasonable agreement with the 3M Co. published thermal conductivity data. Weight loss for both coated and uncoated Si-Ge material produced by G.E. are reported. No significant discrepancies with the results previously obtained on R.C.A. material from the MHW program have been found. Thermal conductivity measurements are also in agreement. The remaining MHW generator on test, Q1-A, has accumulated 26,800 hours and performance remains stable. The performance of the 18 couple modules S/N-1, S/N-2, and S/N-3 to date is summarized. Telemetry data indicate no changes in the trends of degradation of LES 8 and 9 and the Voyager RTGs.

  2. Dynamical centrosymmetry breaking — A novel mechanism for second harmonic generation in graphene

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, David N. [School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS Edinburgh (United Kingdom); Marini, Andrea [ICFO-Institut de Ciencies Fotoniques, 08860 Castelldefels (Barcelona) (Spain); Biancalana, Fabio, E-mail: f.biancalana@hw.ac.uk [School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS Edinburgh (United Kingdom)

    2017-03-15

    We discover an unusual phenomenon that occurs when a graphene monolayer is illuminated by a short and intense pulse at normal incidence. Due to the pulse-induced oscillations of the Dirac cones, a dynamical breaking of the layer’s centrosymmetry takes place, leading to the generation of second harmonic waves. We prove that this result can only be found by using the full Dirac equation and show that the widely used semiconductor Bloch equations fail to reproduce this and some other important physics of graphene. Our results open new windows in the understanding of nonlinear light-matter interactions in a wide variety of new 2D materials with a gapped or ungapped Dirac-like dispersion.

  3. The contribution of parental smoking history and socio-demographic factors to the smoking behavior of Israeli women.

    Science.gov (United States)

    Segal-Engelchin, Dorit; Friedmann, Enav; Cwikel, Julie G

    2014-01-01

    This study examined the interplay between sociodemographic factors and parental smoking history in shaping the smoking behavior of Israeli women (N = 302). The study was conducted in the Negev region, which is characterized by a high proportion of immigrants and high percentage of low socioeconomic and educational groups. The specific objectives of this study were to examine: (1) The prevalence and characteristics of women smokers, ex-smokers and never-smokers; and (2) the contribution of education and parent smoking history to women's current smoking. Low levels of education, being Israeli born or veteran immigrants of European-American origin significantly increased the risk of smoking, whereas an orthodox lifestyle and new immigrant status significantly reduced the likelihood of smoking. Occasional smokers reported significantly higher primary care utilization than never smokers. A significant relationship between smoking and pain, gynecological symptoms and depression was found. Results indicate that childhood exposure to maternal smoking was a significant risk factor for smoking, whereas paternal past smoking negatively affects smoking in women. Also, results show that parental educational level affects women's smoking behavior indirectly by influencing their own educational attainment, which in turn is negatively associated with the likelihood of smoking. Mothers with higher education were more likely to smoke, an effect that was reversed for their daughters. Our results demonstrate how demographic, parental and lifestyle factors affect women's smoking in a multi-ethnic society and highlight the need to examine both generational and intergenerational effects.

  4. Smoke-free laws and direct democracy initiatives on smoking bans in Germany: a systematic review and quantitative assessment.

    Science.gov (United States)

    Kohler, Stefan; Minkner, Philipp

    2014-01-03

    Germany's 16 states regulate smoking differently within health protection principles laid down in the federal law. All state smoke-free laws in Germany have undergone at least one change since taking effect. We systematically review federal and state laws regulating smoking, as well as petitions, popular initiatives and referenda that aimed at changing statutory smoking bans. Data generated through the systematic review were correlated with state smoking rates. The protection from the dangers of secondhand smoke is the primary motive for smoking bans in Germany. The first smoke-free laws affecting smoking in pubs, restaurants and several other public places were introduced in 2007. In 2008, the Federal Constitutional Court of Germany ruled in a leading decision on the smoke-free laws of two states that some common smoking ban exemptions of the introduced smoke-free laws violate the basic right to freely exercise a profession and mandated revisions. All states but Bavaria and Saarland, whose smoking bans were more and less comprehensive than those judged by the constitutional court, respectively, needed to change the smoking ban exemptions to reconcile their smoke-free laws with the constitution. Direct democracy initiatives to change smoking bans were only successful in Bavaria in 2010, but a total of 15 initiatives by citizens' or interest groups attempted to influence non-smokers protection legislation through direct democratic procedures. Early ratification of a smoking ban in a federal state correlates with a higher reduction in the smoking rate from 2005 to 2009 (Spearman's ρ = 0.51, p = 0.04). The federal government structure and direct democratic participation in smoke-free legislation in Germany has produced a diversity of local smoking bans and exemptions.

  5. Smoke-Free Laws and Direct Democracy Initiatives on Smoking Bans in Germany: A Systematic Review and Quantitative Assessment

    Directory of Open Access Journals (Sweden)

    Stefan Kohler

    2014-01-01

    Full Text Available Background: Germany’s 16 states regulate smoking differently within health protection principles laid down in the federal law. All state smoke-free laws in Germany have undergone at least one change since taking effect. Methods: We systematically review federal and state laws regulating smoking, as well as petitions, popular initiatives and referenda that aimed at changing statutory smoking bans. Data generated through the systematic review were correlated with state smoking rates. Results: The protection from the dangers of secondhand smoke is the primary motive for smoking bans in Germany. The first smoke-free laws affecting smoking in pubs, restaurants and several other public places were introduced in 2007. In 2008, the Federal Constitutional Court of Germany ruled in a leading decision on the smoke-free laws of two states that some common smoking ban exemptions of the introduced smoke-free laws violate the basic right to freely exercise a profession and mandated revisions. All states but Bavaria and Saarland, whose smoking bans were more and less comprehensive than those judged by the constitutional court, respectively, needed to change the smoking ban exemptions to reconcile their smoke-free laws with the constitution. Direct democracy initiatives to change smoking bans were only successful in Bavaria in 2010, but a total of 15 initiatives by citizens’ or interest groups attempted to influence non-smokers protection legislation through direct democratic procedures. Early ratification of a smoking ban in a federal state correlates with a higher reduction in the smoking rate from 2005 to 2009 (Spearman’s ρ = 0.51, p = 0.04. Conclusions: The federal government structure and direct democratic participation in smoke-free legislation in Germany has produced a diversity of local smoking bans and exemptions.

  6. Concurrent Phosphorus Recovery and Energy Generation in Mediator-Less Dual Chamber Microbial Fuel Cells: Mechanisms and Influencing Factors

    Directory of Open Access Journals (Sweden)

    Abdullah Almatouq

    2016-03-01

    Full Text Available This study investigated the mechanism and key factors influencing concurrent phosphorus (P recovery and energy generation in microbial fuel cells (MFC during wastewater treatment. Using a mediator-less dual chamber microbial fuel cell operated for 120 days; P was shown to precipitate as struvite when ammonium and magnesium chloride solutions were added to the cathode chamber. Monitoring data for chemical oxygen demand (COD, pH, oxidation reduction potential (ORP and aeration flow rate showed that a maximum 38% P recovery was achieved; and this corresponds to 1.5 g/L, pH > 8, −550 ± 10 mV and 50 mL/min respectively, for COD, pHcathode, ORP and cathode aeration flow rate. More importantly, COD and aeration flow rate were shown to be the key influencing factors for the P recovery and energy generation. Results further show that the maximum P recovery corresponds to 72 mW/m2 power density. However, the energy generated at maximum P recovery was not the optimum; this shows that whilst P recovery and energy generation can be concurrently achieved in a microbial fuel cell, neither can be at the optimal value.

  7. Escherichia coli Quorum-Sensing EDF, A Peptide Generated by Novel Multiple Distinct Mechanisms and Regulated by trans-Translation

    Directory of Open Access Journals (Sweden)

    Sathish Kumar

    2016-01-01

    Full Text Available Eshcerichia coli mazEF is a stress-induced toxin-antitoxin module mediating cell death and requiring a quorum-sensing (QS extracellular death factor (EDF, the pentapeptide NNWNN. Here we uncovered several distinct molecular mechanisms involved in its generation from the zwf mRNA encoding glucose-6-phosphate dehydrogenase. In particular, we show that, under stress conditions, the endoribonuclease MazF cleaves specific ACA sites, thereby generating a leaderless zwf mRNA which is truncated 30 codons after the EDF-encoding region. Since the nascent ribosome peptide exit tunnel can accommodate up to 40 amino acids, this arrangement allows the localization of the EDF residues inside the tunnel when the ribosome is stalled at the truncation site. Moreover, ribosome stalling activates the trans-translation system, which provides a means for the involvement of ClpPX in EDF generation. Furthermore, the trans-translation is described as a regulatory system that attenuated the generation of EDF, leading to low levels of EDF in the single cell. Therefore, the threshold EDF molecule concentration required is achieved only by the whole population, as expected for QS.

  8. Study of particle size distribution and formation mechanism of radioactive aerosols generated in high-energy neutron fields

    CERN Document Server

    Endo, A; Noguchi, H; Tanaka, S; Iida, T; Furuichi, S; Kanda, Y; Oki, Y

    2003-01-01

    The size distributions of sup 3 sup 8 Cl, sup 3 sup 9 Cl, sup 8 sup 2 Br and sup 8 sup 4 Br aerosols generated by irradiations of argon and krypton gases containing di-octyl phthalate (DOP) aerosols with 45 MeV and 65 MeV quasi-monoenergetic neutrons were measured in order to study the formation mechanism of radioactive particles in high energy radiation fields. The effects of the size distribution of the radioactive aerosols on the size of the added DOP aerosols, the energy of the neutrons and the kinds of nuclides were studied. The observed size distributions of the radioactive particles were explained by attachment of the radioactive atoms generated by the neutron-induced reactions to the DOP aerosols. (author)

  9. A distinct translation initiation mechanism generates cryptic peptides for immune surveillance.

    Directory of Open Access Journals (Sweden)

    Shelley R Starck

    Full Text Available MHC class I molecules present a comprehensive mixture of peptides on the cell surface for immune surveillance. The peptides represent the intracellular protein milieu produced by translation of endogenous mRNAs. Unexpectedly, the peptides are encoded not only in conventional AUG initiated translational reading frames but also in alternative cryptic reading frames. Here, we analyzed how ribosomes recognize and use cryptic initiation codons in the mRNA. We find that translation initiation complexes assemble at non-AUG codons but differ from canonical AUG initiation in response to specific inhibitors acting within the peptidyl transferase and decoding centers of the ribosome. Thus, cryptic translation at non-AUG start codons can utilize a distinct initiation mechanism which could be differentially regulated to provide peptides for immune surveillance.

  10. Cross-generational influences on childhood anxiety disorders: pathways and mechanisms

    Science.gov (United States)

    Leckman, James F.; Silverman, Wendy K.; Feldman, Ruth

    2016-01-01

    Anxiety disorders are common across the lifespan, cause severe distress and impairment, and usually have their onset in childhood. Substantial clinical and epidemiological research has demonstrated the existence of links between anxiety and its disorders in children and parents. Research on the pathways and mechanisms underlying these links has pointed to both behavioral and biological systems. This review synthesizes and summarizes several major aspects of this research. Behavioral systems include vicarious learning, social referencing, and modeling of parental anxiety; overly protective or critical parenting styles; and aspects of parental responses to child anxiety including family accommodation of the child’s symptoms. Biological systems include aspects of the prenatal environment affected by maternal anxiety, development and functioning of the oxytocinergic system, and genetic and epigenetic transmission. Implications for the prevention and treatment of child anxiety disorders are discussed, including the potential to enhance child anxiety treatment outcomes through biologically informed parent-based interventions. PMID:27145763

  11. Wear Resistance of Steels with Surface Nanocrystalline Structure Generated by Mechanical-Pulse Treatment.

    Science.gov (United States)

    Nykyforchyn, Hryhoriy; Kyryliv, Volodymyr; Maksymiv, Olha

    2017-12-01

    The influence of the surface mechanical-pulse treatment based on high-speed friction with a rapid cooling by the technological environment on the wear resistance of medium- and high-carbon steels was considered. The treatment due to a severe plastic deformation enabled obtaining the nanocrystalline structure with a grain size of 14-40 nm. A high positive effect of this treatment was obtained not only because of metal nanocrystallization but also thanks to other factors, namely, structural-phase transformations, carbon saturation of the surface due to decomposition of the coolant and the friction coefficient decrease. Higher carbon content leads to better strengthening of the surface, and its microhardness can reach 12 GPa.

  12. Cross-generational influences on childhood anxiety disorders: pathways and mechanisms.

    Science.gov (United States)

    Lebowitz, Eli R; Leckman, James F; Silverman, Wendy K; Feldman, Ruth

    2016-09-01

    Anxiety disorders are common across the lifespan, cause severe distress and impairment, and usually have their onset in childhood. Substantial clinical and epidemiological research has demonstrated the existence of links between anxiety and its disorders in children and parents. Research on the pathways and mechanisms underlying these links has pointed to both behavioral and biological systems. This review synthesizes and summarizes several major aspects of this research. Behavioral systems include vicarious learning, social referencing, and modeling of parental anxiety; overly protective or critical parenting styles; and aspects of parental responses to child anxiety including family accommodation of the child's symptoms. Biological systems include aspects of the prenatal environment affected by maternal anxiety, development and functioning of the oxytocinergic system, and genetic and epigenetic transmission. Implications for the prevention and treatment of child anxiety disorders are discussed, including the potential to enhance child anxiety treatment outcomes through biologically informed parent-based interventions.

  13. Relaxation time diagram for identifying heat generation mechanisms in magnetic fluid hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Enio, E-mail: lima@cab.cnea.gov.ar; De Biasi, Emilio; Zysler, Roberto D.; Vasquez Mansilla, Marcelo; Mojica-Pisciotti, Mary L. [Centro Atómico Bariloche/CONICET (Argentina); Torres, Teobaldo E.; Calatayud, M. Pilar; Marquina, C.; Ricardo Ibarra, M.; Goya, Gerardo F. [Universidad de Zaragoza, Instituto de Nanociencia de Aragón INA (Spain)

    2014-12-15

    We present a versatile diagram to envisage the dominant relaxation mechanism of single-domain magnetic nanoparticles (MNPs) under alternating magnetic fields, as those used in magnetic fluid hyperthermia (MFH). The diagram allows estimating the heating efficiency, measured by the Specific Power Absorption (SPA), originated in the magnetic and viscous relaxation times of single-domain MNPs for a given frequency of the ac magnetic field (AFM). The diagram has been successfully applied to different colloids, covering a wide variety of MNPs with different magnetic anisotropy and particle size, and dispersed in different viscous liquid carriers. From the general diagram, we derived a specific chart based on the Linear Response Theory in order to easily estimate the experimental condition for the optimal SPA values of most colloids currently used in MFH.

  14. Use of mutagenesis, genetic mapping and next generation transcriptomics to investigate insecticide resistance mechanisms.

    Directory of Open Access Journals (Sweden)

    Predrag Kalajdzic

    Full Text Available Insecticide resistance is a worldwide problem with major impact on agriculture and human health. Understanding the underlying molecular mechanisms is crucial for the management of the phenomenon; however, this information often comes late with respect to the implementation of efficient counter-measures, particularly in the case of metabolism-based resistance mechanisms. We employed a genome-wide insertional mutagenesis screen to Drosophila melanogaster, using a Minos-based construct, and retrieved a line (MiT[w(-]3R2 resistant to the neonicotinoid insecticide Imidacloprid. Biochemical and bioassay data indicated that resistance was due to increased P450 detoxification. Deep sequencing transcriptomic analysis revealed substantial over- and under-representation of 357 transcripts in the resistant line, including statistically significant changes in mixed function oxidases, peptidases and cuticular proteins. Three P450 genes (Cyp4p2, Cyp6a2 and Cyp6g1 located on the 2R chromosome, are highly up-regulated in mutant flies compared to susceptible Drosophila. One of them (Cyp6g1 has been already described as a major factor for Imidacloprid resistance, which validated the approach. Elevated expression of the Cyp4p2 was not previously documented in Drosophila lines resistant to neonicotinoids. In silico analysis using the Drosophila reference genome failed to detect transcription binding factors or microRNAs associated with the over-expressed Cyp genes. The resistant line did not contain a Minos insertion in its chromosomes, suggesting a hit-and-run event, i.e. an insertion of the transposable element, followed by an excision which caused the mutation. Genetic mapping placed the resistance locus to the right arm of the second chromosome, within a ∼1 Mb region, where the highly up-regulated Cyp6g1 gene is located. The nature of the unknown mutation that causes resistance is discussed on the basis of these results.

  15. Mechanisms of Left-Right Coordination in Mammalian Locomotor Pattern Generation Circuits: A Mathematical Modeling View

    Science.gov (United States)

    Talpalar, Adolfo E.; Rybak, Ilya A.

    2015-01-01

    The locomotor gait in limbed animals is defined by the left-right leg coordination and locomotor speed. Coordination between left and right neural activities in the spinal cord controlling left and right legs is provided by commissural interneurons (CINs). Several CIN types have been genetically identified, including the excitatory V3 and excitatory and inhibitory V0 types. Recent studies demonstrated that genetic elimination of all V0 CINs caused switching from a normal left-right alternating activity to a left-right synchronized “hopping” pattern. Furthermore, ablation of only the inhibitory V0 CINs (V0D subtype) resulted in a lack of left-right alternation at low locomotor frequencies and retaining this alternation at high frequencies, whereas selective ablation of the excitatory V0 neurons (V0V subtype) maintained the left–right alternation at low frequencies and switched to a hopping pattern at high frequencies. To analyze these findings, we developed a simplified mathematical model of neural circuits consisting of four pacemaker neurons representing left and right, flexor and extensor rhythm-generating centers interacting via commissural pathways representing V3, V0D, and V0V CINs. The locomotor frequency was controlled by a parameter defining the excitation of neurons and commissural pathways mimicking the effects of N-methyl-D-aspartate on locomotor frequency in isolated rodent spinal cord preparations. The model demonstrated a typical left-right alternating pattern under control conditions, switching to a hopping activity at any frequency after removing both V0 connections, a synchronized pattern at low frequencies with alternation at high frequencies after removing only V0D connections, and an alternating pattern at low frequencies with hopping at high frequencies after removing only V0V connections. We used bifurcation theory and fast-slow decomposition methods to analyze network behavior in the above regimes and transitions between them. The model

  16. Epigenetic Signatures of Cigarette Smoking

    NARCIS (Netherlands)

    R. Joehanes (Roby); Just, A.C. (Allan C.); R.E. Marioni (Riccardo); L.C. Pilling (Luke); L.M. Reynolds (Lindsay); Mandaviya, P.R. (Pooja R.); W. Guan (Weihua); Xu, T. (Tao); C.E. Elks (Cathy); Aslibekyan, S. (Stella); H. Moreno-Macías (Hortensia); J.A. Smith (Jennifer A); J. Brody (Jennifer); Dhingra, R. (Radhika); P. Yousefi (Paul); J.S. Pankow (James); Kunze, S. (Sonja); Shah, S.H. (Sonia H.); A.F. McRae (Allan F.); K. Lohman (Kurt); Sha, J. (Jin); D. Absher (Devin); L. Ferrucci (Luigi); Zhao, W. (Wei); E.W. Demerath (Ellen); J. Bressler (Jan); M.L. Grove (Megan); T. Huan (Tianxiao); C. Liu (Chunyu); Mendelson, M.M. (Michael M.); C. Yao (Chen); D.P. Kiel (Douglas P.); A. Peters (Annette); R. Wang-Sattler (Rui); P.M. Visscher (Peter); N.R. Wray (Naomi); J.M. Starr (John); Ding, J. (Jingzhong); Rodriguez, C.J. (Carlos J.); N.J. Wareham (Nick); Irvin, M.R. (Marguerite R.); Zhi, D. (Degui); M. Barrdahl (Myrto); P. Vineis (Paolo); Ambatipudi, S. (Srikant); A.G. Uitterlinden (André); A. Hofman (Albert); Schwartz, J. (Joel); Colicino, E. (Elena); Hou, L. (Lifang); Vokonas, P.S. (Pantel S.); D.G. Hernandez (Dena); A. Singleton (Andrew); S. Bandinelli (Stefania); S.T. Turner (Stephen); E.B. Ware (Erin B.); Smith, A.K. (Alicia K.); T. Klengel (Torsten); E.B. Binder (Elisabeth B.); B.M. Psaty (Bruce); K.D. Taylor (Kent); S.A. Gharib (Sina); Swenson, B.R. (Brenton R.); Liang, L. (Liming); D.L. Demeo (Dawn L.); G.T. O'Connor (George); Z. Herceg (Zdenko); Ressler, K.J. (Kerry J.); K.N. Conneely (Karen N.); N. Sotoodehnia (Nona); Kardia, S.L.R. (Sharon L. R.); D. Melzer (David); A.A. Baccarelli (Andrea A.); J.B.J. van Meurs (Joyce); I. Romieu (Isabelle); D.K. Arnett (Donna); Ong, K.K. (Ken K.); Y. Liu (YongMei); M. Waldenberger (Melanie); I.J. Deary (Ian J.); M. Fornage (Myriam); D. Levy (Daniel); S.J. London (Stephanie J.)

    2016-01-01

    textabstractBackground-DNA methylation leaves a long-term signature of smoking exposure and is one potential mechanism by which tobacco exposure predisposes to adverse health outcomes, such as cancers, osteoporosis, lung, and cardiovascular disorders. Methods and Results-To comprehensively determine

  17. Smoking and Pregnancy

    Science.gov (United States)

    Smoking and Pregnancy Smoking can cause problems for a woman trying to become pregnant or who is already pregnant, and for her baby ... too early • Pregnancy occurs outside of the womb Smoking causes these health effects. Smoking could cause these ...

  18. All about Quitting Smoking

    Science.gov (United States)

    Toolkit No. 7 All About Quitting Smoking Are you ready to quit smoking? You can find a way to do it. Once you’ve quit, you’ll feel healthier ... ve quit. What are the benefits of quitting smoking? You’ve probably already heard that smoking is ...

  19. The interaction of meal-related, rhythmic and homeostatic mechanisms and the generation of thirst and drinking

    Directory of Open Access Journals (Sweden)

    R.F. Johnson

    1997-04-01

    Full Text Available One of the primary goals of the study of thirst is to understand why drinking occurs under ad libitum or natural conditions. An appreciation of the experimental strategies applied by physiologists studying thirst from different perspectives can facilitate progress toward understanding the natural history of drinking behavior. Drinking research carried out using three separate perspectives - homeostatic, circadian rhythms, and food-associated - generates types of information about the mechanisms underlying drinking behavior. By combining research strategies and methods derived from each of these approaches, it has been possible to gain new information that increases our appreciation of the interactions between homeostatic mechanisms and circadian rhythms in the modulation of water intake and how these might be related to drinking associated with food intake under near natural conditions

  20. Thermoelectric generator testing and RTG degradation mechanisms evaluation. Progress report No. 37

    Energy Technology Data Exchange (ETDEWEB)

    Lockwood, A.; Shields, V.

    1980-09-01

    The n-type selenide legs after 16,500 hours continue to show reasonable agreement with the 3M Co. published thermal conductivity data. In the ingradient testing after 17,000 hours the 3 surviving n-legs (out of 5) show serious degradation in power to load. Small scale ratcheting has been observed on the four p-legs but no large scale effects. Weight loss for both coated and uncoated material produced by G.E. are reported. No significant discrepancies with the results previously obtained on R.C.A. material from the MHW program have been found. Thermal conductivity measurements are also in agreement. The remaining MHW generator on test, Q1-A, has accumulated 25,600 hours and performance remains stable. The 18 couple modules S/N-1 and -3 previously tested at RCA show no significant change in operation during the current JPL testing. No changes in the trends of degradation of LES 8 and 9 and the Voyager RTGs have been observed.

  1. Thermoelectric generator testing and RTG degradation mechanisms evaluation. Progress report No. 36

    Energy Technology Data Exchange (ETDEWEB)

    Lockwood, A.; Shields, V.

    1980-07-01

    The n-type selenide legs after 15,000 hours continue to show reasonable agreement with the 3M Co. published thermal conductivity data. In the ingradient testing after 16,500 hours the 3 surviving n-legs (out of 5) show serious degradation in power to load. Weight loss and thermoelectricity property measurements on the first samples of material produced by G.E. continue to correspond to the results previously obtained on R.C.A. material from the MHW program. The remaining MHW generator on test, Q1-A, has accumulated 23,679 hours and performance remains stable. The 18 couple modules S/N-1 and -3 previously tested at RCA show no significant change in operation during the current JPL testing. A comparison of LES 8/9 RTG's with an improved version of DEGRA is shown. No changes in the trends of degradation of LES 8 and 9 and the Voyager RTGs have been observed.

  2. Maximum power point tracking-based control algorithm for PMSG wind generation system without mechanical sensors

    International Nuclear Information System (INIS)

    Hong, Chih-Ming; Chen, Chiung-Hsing; Tu, Chia-Sheng

    2013-01-01

    Highlights: ► This paper presents MPPT based control for optimal wind energy capture using RBFN. ► MPSO is adopted to adjust the learning rates to improve the learning capability. ► This technique can maintain the system stability and reach the desired performance. ► The EMF in the rotating reference frame is utilized in order to estimate speed. - Abstract: This paper presents maximum-power-point-tracking (MPPT) based control algorithms for optimal wind energy capture using radial basis function network (RBFN) and a proposed torque observer MPPT algorithm. The design of a high-performance on-line training RBFN using back-propagation learning algorithm with modified particle swarm optimization (MPSO) regulating controller for the sensorless control of a permanent magnet synchronous generator (PMSG). The MPSO is adopted in this study to adapt the learning rates in the back-propagation process of the RBFN to improve the learning capability. The PMSG is controlled by the loss-minimization control with MPPT below the base speed, which corresponds to low and high wind speed, and the maximum energy can be captured from the wind. Then the observed disturbance torque is feed-forward to increase the robustness of the PMSG system

  3. Mitotic Spindle Asymmetry: A Wnt/PCP-Regulated Mechanism Generating Asymmetrical Division in Cortical Precursors

    Directory of Open Access Journals (Sweden)

    Delphine Delaunay

    2014-01-01

    Full Text Available The regulation of asymmetric cell division (ACD during corticogenesis is incompletely understood. We document that spindle-size asymmetry (SSA between the two poles occurs during corticogenesis and parallels ACD. SSA appears at metaphase and is maintained throughout division, and we show it is necessary for proper neurogenesis. Imaging of spindle behavior and division outcome reveals that neurons preferentially arise from the larger-spindle pole. Mechanistically, SSA magnitude is controlled by Wnt7a and Vangl2, both members of the Wnt/planar cell polarity (PCP-signaling pathway, and relayed to the cell cortex by P-ERM proteins. In vivo, Vangl2 and P-ERM downregulation promotes early cell-cycle exit and prevents the proper generation of late-born neurons. Thus, SSA is a core component of ACD that is conserved in invertebrates and vertebrates and plays a key role in the tight spatiotemporal control of self-renewal and differentiation during mammalian corticogenesis.

  4. Mechanism of Cisplatin-Induced Cytotoxicity Is Correlated to Impaired Metabolism Due to Mitochondrial ROS Generation

    Science.gov (United States)

    Shim, Wooyoung; Anwar, Muhammad Ayaz; Kwon, Ji-Woong; Kwon, Hyuk-Kwon; Kim, Hyung Joong; Jeong, Hyobin; Kim, Hwan Myung; Hwang, Daehee; Kim, Hyung Sik; Choi, Sangdun

    2015-01-01

    The chemotherapeutic use of cisplatin is limited by its severe side effects. In this study, by conducting different omics data analyses, we demonstrated that cisplatin induces cell death in a proximal tubular cell line by suppressing glycolysis- and tricarboxylic acid (TCA)/mitochondria-related genes. Furthermore, analysis of the urine from cisplatin-treated rats revealed the lower expression levels of enzymes involved in glycolysis, TCA cycle, and genes related to mitochondrial stability and confirmed the cisplatin-related metabolic abnormalities. Additionally, an increase in the level of p53, which directly inhibits glycolysis, has been observed. Inhibition of p53 restored glycolysis and significantly reduced the rate of cell death at 24 h and 48 h due to p53 inhibition. The foremost reason of cisplatin-related cytotoxicity has been correlated to the generation of mitochondrial reactive oxygen species (ROS) that influence multiple pathways. Abnormalities in these pathways resulted in the collapse of mitochondrial energy production, which in turn sensitized the cells to death. The quenching of ROS led to the amelioration of the affected pathways. Considering these observations, it can be concluded that there is a significant correlation between cisplatin and metabolic dysfunctions involving mROS as the major player. PMID:26247588

  5. Mechanisms of generation of membrane potential resonance in a neuron with multiple resonant ionic currents.

    Directory of Open Access Journals (Sweden)

    David M Fox

    2017-06-01

    Full Text Available Neuronal membrane potential resonance (MPR is associated with subthreshold and network oscillations. A number of voltage-gated ionic currents can contribute to the generation or amplification of MPR, but how the interaction of these currents with linear currents contributes to MPR is not well understood. We explored this in the pacemaker PD neurons of the crab pyloric network. The PD neuron MPR is sensitive to blockers of H- (IH and calcium-currents (ICa. We used the impedance profile of the biological PD neuron, measured in voltage clamp, to constrain parameter values of a conductance-based model using a genetic algorithm and obtained many optimal parameter combinations. Unlike most cases of MPR, in these optimal models, the values of resonant- (fres and phasonant- (fϕ = 0 frequencies were almost identical. Taking advantage of this fact, we linked the peak phase of ionic currents to their amplitude, in order to provide a mechanistic explanation the dependence of MPR on the ICa gating variable time constants. Additionally, we found that distinct pairwise correlations between ICa parameters contributed to the maintenance of fres and resonance power (QZ. Measurements of the PD neuron MPR at more hyperpolarized voltages resulted in a reduction of fres but no change in QZ. Constraining the optimal models using these data unmasked a positive correlation between the maximal conductances of IH and ICa. Thus, although IH is not necessary for MPR in this neuron type, it contributes indirectly by constraining the parameters of ICa.

  6. Electronic transport mechanism and photocurrent generations of single-crystalline InN nanowires

    Science.gov (United States)

    Lee, Sunghun; Lee, Wonjoo; Seo, Kwanyong; Kim, Jinhee; Han, Sung-Hwan; Kim, Bongsoo

    2008-10-01

    Nanodevices using individual indium nitride nanowires are fabricated by e-beam lithography. The nanowires have diameters of 40-80 nm, lengths up to several tens of micrometres and single-crystalline nature. We observed ohmic I-V behaviour of InN nanowires above nearly 100 K, which is consistent with the pinning Fermi level of the metal electrode near the conduction band edge of InN nanowire. At low temperatures, the device shows typical semiconductor behaviour along with a quantum tunnelling effect through the Schottky barrier rather than thermally activated transport. The activation energy calculated above and below 80 K is 28.2 and 5.08 meV, respectively. We have also fabricated a photocurrent generation device using InN nanowires. The photocurrent of an acceptor-sensitizer dyad with di-(3-aminopropyl)-viologen (DAPV) and a Ru complex on an InN nanowires/ITO plate was 8.3 nA cm-2, which increased by 62.7% compared to that without InN nanowire layers.

  7. THYROID FUNCTION Quitting smoking-transient risk of autoimmune hypothyroidism

    NARCIS (Netherlands)

    Wiersinga, Wilmar M.

    2012-01-01

    Smoking is a risk factor for Graves disease. However, Carle et al. have demonstrated that individuals have a transient increased risk of developing overt autoimmune hypothyroidism in the first 2 years after quitting smoking. The mechanisms involved in these two opposing effects of smoking on the

  8. Development of next generation consumable technologies for chemical mechanical planarization of copper/low K devices

    Science.gov (United States)

    Keleher, Jason J.

    Chemical Mechanical Planarization (CMP) has become the key planarization technology for the fabrication of ultra large-scale integration (ULSI) silicon devices that contain sub-quarter micron metal and dielectric lines. The rapid integration of copper as the interconnect material into IC production has placed a high demand on Cu CMP slurry development. Key issues in CMP today include reduction of surface defectivity and enhancement of planarization efficiency. More specifically, the polished surface should be free of defects such as scratches, pits, corrosion spots, trench copper loss, and residue particles. This dissertation will explore the use of Abrasive Free and Novel Abrasive systems as a plausible solution for the planarization Cu/low K devices. For copper/low K CMP, one of the most promising strategies to accomplishing these goals is an Abrasive-Free Process (AFP). By eliminating abrasive particles from the process, either free or fixed to the pad, it has been anticipated and realized that defects such as severe scratching, particle contamination and slurry instability via particle aggregation or settling will be significantly reduced. In addition, with proper formulation, an abrasive free process can also yield an excellent over polishing window and desired step function of pressure for material removal rate. Coupled with a supramolecular design, some of the characteristic advantages seen in abrasive containing systems, such as step height reduction efficiency, can be realized without the side effects often introduced from solid particles. The second portion of this dissertation deals with the use of novel hydrophobic particles such as diamond and boron nitride. Hydrophobic particles have received much less attention because of issues related to the stability when placed in an aqueous media as well as the inability of the particles to interact with the abraded material. In general the ability of the hydrophobic particle to interact with the oxidized or

  9. Momentary smoking context as a mediator of the relationship between SES and smoking.

    Science.gov (United States)

    Jahnel, Tina; Ferguson, Stuart G; Shiffman, Saul; Thrul, Johannes; Schüz, Benjamin

    2017-12-15

    There is a well-established socioeconomic gradient in smoking behavior: those with lower socioeconomic status smoke more. However, much less is known about the mechanisms explaining how SES is linked to smoking. This study takes a social-ecological perspective by examining whether socioeconomic status affects smoking behavior by differential exposure to places where smoking is allowed. Exposure to smoking restrictions was assessed in real-time using Ecological Momentary Assessment methods. A sample of 194 daily smokers, who were not attempting to quit, recorded their smoking and information about situational and contextual factors for three weeks using an electronic diary. We tested whether a smoker's momentary context mediated the relationship between socioeconomic status (educational attainment) and cigarettes smoked per day (CPD). Momentary context was operationalized as the proportion of random assessments answered in locations where smoking was allowed versus where smoking was not allowed. Data were analysed using multilevel regression (measurements nested within participants) with a lower level mediation model (2-1-1 mediation). Although no significant direct effect of SES on CPD were observed, there was a significant indirect effect of SES on CPD via the momentary context. Compared to participants with higher education, lower educated participants were more likely to encounter places where smoking was allowed, and this in turn, was associated with a higher number of CPD. These findings suggest that SES is associated with smoking at least partially via differential exposure to smoking-friendly environments, with smokers from lower SES backgrounds accessing more places where smoking is allowed. Implications for current smoke-free legislation are discussed. Copyright © 2017. Published by Elsevier Ltd.

  10. Smoke from Colorado Wildfires

    Science.gov (United States)

    2002-01-01

    The Hayman fire, situated about 65 kilometers southwest of Denver, Colorado, is the largest fire ever recorded in that state. The amount and distribution of smoke from the Hayman fire and from the Ponil Complex fires south of the New Mexico-Colorado border are portrayed in these views from the Multi-angle Imaging SpectroRadiometer (MISR). The images were captured on June 9, 2002, on the second day of the Hayman fire, when only about 13 percent of the total 137,000 acres eventually consumed had been scorched.The image at top-left was acquired by MISR's most oblique (70-degree) forward-viewing camera, and the view at bottom-left was captured by MISR's 26-degree forward-viewing camera. Both left-hand panels are 'false color' views, utilizing near-infrared, red, and blue spectral bands displayed as red, green and blue respectively. With this spectral combination, highly vegetated areas appear red. At top right is a map of aerosol optical depth. This map utilizes the capability of the oblique view angles to measure the abundance of particles in the atmosphere. Haze distributed across the eastern part of the state is indicated by a large number of green pixels, and areas where no retrieval occurred are shown in dark grey. The more oblique perspective utilized within the top panels enhances the appearance of smoke and reveals the haze. In the lower left-hand panel the view is closer to nadir (downward-looking). Here the smoke plumes appear more compact and the haze across eastern Colorado is not detected. The lower right-hand panel is a stereoscopically derived height field that echoes the compact shape of the smoke plumes in the near-nadir image. Results indicate that the smoke plumes reached altitudes of a few kilometers above the surface terrain, or about the same height as the small clouds that appear orange along the bottom edge to the left of center.Data used in these visualizations were generated as part of operational processing at the Atmospheric Sciences Data

  11. MONO, DI and TRI SSRs data extraction & storage from 1403 virus genomes with next generation retrieval mechanism

    Directory of Open Access Journals (Sweden)

    K.V.S.S.R. Murthy

    2017-08-01

    Full Text Available Now a day׳s SSRs occupy the dominant role in different areas of bio-informatics like new virus identification, DNA finger printing, paternity & maternity identification, disease identification, future disease expectations and possibilities etc., Due to their wide applications in various fields and their significance, SSRs have been the area of interest for many researchers. In the SSRs extraction, retrieval algorithms are used; if retrieval algorithms quality is improved then automatically SSRs extraction system will achieve the most relevant results. For this retrieval purpose in this paper a new retrieval mechanism is proposed which will extracted the MONO, DI and TRI patterns. To extract the MONO, DI and TRI patterns using proposed retrieval mechanism in this paper, DNA sequence of 1403 virus genome data sets are considered and different MONO, DI and TRI patterns are searched in the data genome sequence file. The proposed Next Generation Sequencing (NGS retrieval mechanism extracted the MONO, DI and TRI patterns without missing anything. It is observed that the retrieval mechanism reduces the unnecessary comparisons. Finally the extracted SSRs provide the useful, single view and useful resource to researchers.

  12. Elastic hydrogel as a sensor for detection of mechanical stress generated by single cells grown in three-dimensional environment.

    Science.gov (United States)

    Huang, Jianyong; Wang, Liangli; Xiong, Chunyang; Yuan, Fan

    2016-08-01

    Cell volume growth occurs in all living tissues. The growth exerts mechanical stresses on surrounding tissues that may alter tissue microenvironment, and have significant implications in health and diseases. However, the level of growth stress generated by single cells in three-dimensional (3D) environment remains to be determined. To this end, we developed a growth force microscopy technique to determine 3D distribution of the stress. The technique was based on encapsulation of cells in elastic hydrogels, and involved 3D particle tracking and mechanical analysis of gel deformation. Data from the study demonstrated that the growth stress was dynamic, and the stress distribution at the gel-cell interface was correlated inversely to the mean surface curvature or the distance to the geometric center of the cell. The stress averaged over the cell surface increased with increasing gel stiffness, suggesting that cells could alter growth stress in response to stiffness change in microenvironment. These findings suggested that the elastic hydrogel-based microscopy technique had a potential to provide new insights into mechanisms of mechanical interactions between cell and its microenvironment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. MONO, DI and TRI SSRs data extraction & storage from 1403 virus genomes with next generation retrieval mechanism.

    Science.gov (United States)

    Murthy, K V S S R; Satyanarayana, K V V

    2017-08-01

    Now a day׳s SSRs occupy the dominant role in different areas of bio-informatics like new virus identification, DNA finger printing, paternity & maternity identification, disease identification, future disease expectations and possibilities etc., Due to their wide applications in various fields and their significance, SSRs have been the area of interest for many researchers. In the SSRs extraction, retrieval algorithms are used; if retrieval algorithms quality is improved then automatically SSRs extraction system will achieve the most relevant results. For this retrieval purpose in this paper a new retrieval mechanism is proposed which will extracted the MONO, DI and TRI patterns. To extract the MONO, DI and TRI patterns using proposed retrieval mechanism in this paper, DNA sequence of 1403 virus genome data sets are considered and different MONO, DI and TRI patterns are searched in the data genome sequence file. The proposed Next Generation Sequencing (NGS) retrieval mechanism extracted the MONO, DI and TRI patterns without missing anything. It is observed that the retrieval mechanism reduces the unnecessary comparisons. Finally the extracted SSRs provide the useful, single view and useful resource to researchers.

  14. Mechanisms by Which Metabolic Reprogramming in GSD1 Liver Generates a Favorable Tumorigenic Environment

    Directory of Open Access Journals (Sweden)

    Monika Gjorgjieva PhD Student

    2016-11-01

    Full Text Available Glycogen storage disease type 1 (GSD1 is an inherited disorder caused by impaired glucose 6-phosphatase activity. This impairment translates into the inhibition of endogenous glucose production and the subsequent accumulation of cellular glucose 6-phosphate. Excess glucose 6-phosphate enhances glycolysis, increases the production of fatty acids, uric acid, and lactate, causes hepatomegaly due to glycogen and lipid accumulation, and finally results in liver tumor development. Although the exact mechanisms of tumorigenesis in patients with GSD1 remain unclear, GSD1 hepatocytes undergo a Warburg-like metabolic switch. The consequent hyperactivation of specific metabolic pathways renders GSD1 hepatocytes susceptible to tumor development, presumably by providing the building blocks and energy required for cell proliferation. In addition to this, enhanced apoptosis in GSD1 may promote mitotic activity and hence result in DNA replication errors, thereby contributing to tumorigenesis. Increased carbohydrate responsive element-binding protein (ChREBP and mammalian target of rapamycin (mTOR activity and impaired AMP-activated protein kinase (AMPK function likely play key roles in these pro-oncogenic processes.

  15. Teaching Practice generated stressors and coping mechanisms among student teachers in Zimbabwe

    Directory of Open Access Journals (Sweden)

    John S Mapfumo

    2012-01-01

    Full Text Available We sought to establish stressors and coping mechanisms for student teachers on Teaching Practice from a Christian-related university and a government-owned teachers' college in Zimbabwe. The sample was made up of 77 participants (38 females, 39 males. Thirty-two participants were from the university and 45 were from the teachers' college. A questionnaire and an interview schedule were used to collect data. Frequencies and percentages were used in quantitative data analysis while qualitative data were thematically analysed. The main stressors revealed were problems with difficult learners, low allowances, heavy workload, and shortage of teaching and learning aids and, to some extent, supervision-related matters and the effect of the protracted industrial action by serving teachers that overlapped with the Teaching Practice period in the study. Most coping strategies were in the form of social-support networks, particularly interactions with family and friends. Student teachers suggested a number of actions to be taken to reduce the related stress. Recommendations are made.

  16. Mechanical removal of dendritic cell-generating non-classical monocytes via ex vivo lung perfusion.

    Science.gov (United States)

    Stone, John P; Sevenoaks, Hannah; Sjöberg, Trygve; Steen, Stig; Yonan, Nizar; Fildes, James E

    2014-08-01

    Ex vivo lung perfusion (EVLP) is a novel procedure designed to rapidly assess and recondition unusable donor lungs for transplantation (LTx). EVLP may reduce graft immunogenicity and allorecognition via removal of passenger leukocytes. We aimed to explore this hypothesis using human EVLP and in vitro analysis. Explanted human lungs (n = 7) underwent standard EVLP. Perfusate samples and the leukocyte filter were collected, and cells characterized via flow cytometry. Isolated alveolar monocytes (from post-LTx bronchoalveolar lavage) were differentiated to dendritic cells and characterized (n = 10). An in vitro (air epithelial-liquid endothelial) lung model was utilized to evaluate monocyte migration and differentiation within the lung. Non-classical monocytes (NCM, normally <1% of total white blood cell repertoire) mobilized within 30 minutes of EVLP and represented 80.04% of the passenger leukocyte population. This subset readily differentiated to dendritic cells and secreted pro-inflammatory cytokines (interferon-γ and interleukin-2) after stimulation. NCM rapidly diapedesed from the vascular bed to the alveolus and, when cultured on the alveolus, differentiated to dendritic cells with inflammatory phenotypes. The lung possesses a reservoir of NCM, which can readily diapedese to the alveolus or mobilize in the circulation. After activation, NCM differentiate to inflammatory dendritic cells with T-cell co-stimulatory capacity. EVLP may impart additional benefits after LTx via the removal of passenger monocytes, which may represent a previously unidentified beneficial mechanism of action. Copyright © 2014 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  17. Automatic generation of virtual worlds from architectural and mechanical CAD models

    International Nuclear Information System (INIS)

    Szepielak, D.

    2003-12-01

    Accelerator projects like the XFEL or the planned linear collider TESLA involve extensive architectural and mechanical design work, resulting in a variety of CAD models. The CAD models will be showing different parts of the project, like e.g. the different accelerator components or parts of the building complexes, and they will be created and stored by different groups in different formats. A complete CAD model of the accelerator and its buildings is thus difficult to obtain and would also be extremely huge and difficult to handle. This thesis describes the design and prototype development of a tool which automatically creates virtual worlds from different CAD models. The tool will enable the user to select a required area for visualization on a map, and then create a 3D-model of the selected area which can be displayed in a web-browser. The thesis first discusses the system requirements and provides some background on data visualization. Then, it introduces the system architecture, the algorithms and the used technologies, and finally demonstrates the capabilities of the system using two case studies. (orig.)

  18. Smoking-a true periodontal hazard

    Directory of Open Access Journals (Sweden)

    Mani Ameet M, Mani Shubhangi A, Tejnani Avneesh H, Gupta Ankit

    2013-04-01

    Full Text Available It is now well established that tobacco use in general and cigarette smoking in particular, is a major risk factor in the incidence and severity of several forms of periodontal diseases.A large number of studies have been published in the dental literature regarding this possible role. Much of the literature has also indicated that smokers affected with periodontitis respond less favourably to periodontal treatment be it non-surgical, surgical or regenerative. Numerous studies of the potential mechanisms whereby smoking tobacco may predispose to periodontal disease have been conducted, and it appears that smoking may affect the vasculature, the humoral immune system, and the cellular immune and inflammatory systems, and have effects throughout the cytokine and adhesion molecule network. The aim of this review is to consider the evidence for the association between smoking and periodontal diseases and to highlight the biological mechanisms whereby smoking may affect the periodontium.

  19. Coordination of fictive motor activity in the larval zebrafish is generated by non-segmental mechanisms.

    Directory of Open Access Journals (Sweden)

    Timothy D Wiggin

    Full Text Available The cellular and network basis for most vertebrate locomotor central pattern generators (CPGs is incompletely characterized, but organizational models based on known CPG architectures have been proposed. Segmental models propose that each spinal segment contains a circuit that controls local coordination and sends longer projections to coordinate activity between segments. Unsegmented/continuous models propose that patterned motor output is driven by gradients of neurons and synapses that do not have segmental boundaries. We tested these ideas in the larval zebrafish, an animal that swims in discrete episodes, each of which is composed of coordinated motor bursts that progress rostrocaudally and alternate from side to side. We perturbed the spinal cord using spinal transections or strychnine application and measured the effect on fictive motor output. Spinal transections eliminated episode structure, and reduced both rostrocaudal and side-to-side coordination. Preparations with fewer intact segments were more severely affected, and preparations consisting of midbody and caudal segments were more severely affected than those consisting of rostral segments. In reduced preparations with the same number of intact spinal segments, side-to-side coordination was more severely disrupted than rostrocaudal coordination. Reducing glycine receptor signaling with strychnine reversibly disrupted both rostrocaudal and side-to-side coordination in spinalized larvae without disrupting episodic structure. Both spinal transection and strychnine decreased the stability of the motor rhythm, but this effect was not causal in reducing coordination. These results are inconsistent with a segmented model of the spinal cord and are better explained by a continuous model in which motor neuron coordination is controlled by segment-spanning microcircuits.

  20. Electrostatic mode coupling at 2ω/sub UH/: a generation mechanism for auroral kilometric radiation

    International Nuclear Information System (INIS)

    Barbosa, D.D.

    1976-01-01

    The instability of a low density, electron beam drifting along a magnetic field to nearly perpendicular propagating electrostatic waves near the upper hybrid frequency is investigated for application to an auroral environment. It was found that 4 to 10 KeV beams can interact significantly with the background plasma through anomalous cyclotron resonances which extend the range of unstable parallel wave numbers over a large region of wave number space. This region can include a nonconvective hot spot where the group velocity of the unstable waves approaches zero. Positive slope in the total distribution function is not a necessary requirement for instability; the broken symmetry along the field can allow the transfer of beam drift energy to electrostatic wave turbulence. Using Gurnett's (1974) polar ionospheric model for a representative auroral field line modeled as dipolar (L = 8), one infers that certain heights favor generation of enhanced, beamdriven electrostatic turbulence. Those regions are in the vicinity of where ω/sub UH//Ω/sub c/ approx. 3/2 with an excursion from this value depending on beam parameters. We speculate that electrostatic turbulence will heat the background electrons to a limiting temperature such that the instability becomes marginally effective. This limiting temperature is estimated for auroral beam-plasma conditions as 1 to 6 eV. Quasi-linear beam moment equations are developed to compute an upper bound to electrostatic wave amplitudes that can be maintained by the beam. We find that energy densities approaching E 2 /8πnT approx. 1 over auroral scale lengths can result in effective energy transfer from the beam to the plasma

  1. Coordination of fictive motor activity in the larval zebrafish is generated by non-segmental mechanisms.

    Science.gov (United States)

    Wiggin, Timothy D; Peck, Jack H; Masino, Mark A

    2014-01-01

    The cellular and network basis for most vertebrate locomotor central pattern generators (CPGs) is incompletely characterized, but organizational models based on known CPG architectures have been proposed. Segmental models propose that each spinal segment contains a circuit that controls local coordination and sends longer projections to coordinate activity between segments. Unsegmented/continuous models propose that patterned motor output is driven by gradients of neurons and synapses that do not have segmental boundaries. We tested these ideas in the larval zebrafish, an animal that swims in discrete episodes, each of which is composed of coordinated motor bursts that progress rostrocaudally and alternate from side to side. We perturbed the spinal cord using spinal transections or strychnine application and measured the effect on fictive motor output. Spinal transections eliminated episode structure, and reduced both rostrocaudal and side-to-side coordination. Preparations with fewer intact segments were more severely affected, and preparations consisting of midbody and caudal segments were more severely affected than those consisting of rostral segments. In reduced preparations with the same number of intact spinal segments, side-to-side coordination was more severely disrupted than rostrocaudal coordination. Reducing glycine receptor signaling with strychnine reversibly disrupted both rostrocaudal and side-to-side coordination in spinalized larvae without disrupting episodic structure. Both spinal transection and strychnine decreased the stability of the motor rhythm, but this effect was not causal in reducing coordination. These results are inconsistent with a segmented model of the spinal cord and are better explained by a continuous model in which motor neuron coordination is controlled by segment-spanning microcircuits.

  2. Detection of stimulus deviance within primate primary auditory cortex: intracortical mechanisms of mismatch negativity (MMN) generation.

    Science.gov (United States)

    Javitt, D C; Steinschneider, M; Schroeder, C E; Vaughan, H G; Arezzo, J C

    1994-12-26

    Mismatch negativity (MMN) is a cognitive, auditory event-related potential (AEP) that reflects preattentive detection of stimulus deviance and indexes the operation of the auditory sensory ('echoic') memory system. MMN is elicited most commonly in an auditory oddball paradigm in which a sequence of repetitive standard stimuli is interrupted infrequently and unexpectedly by a physically deviant 'oddball' stimulus. Electro- and magnetoencephalographic dipole mapping studies have localized the generators of MMN to supratemporal auditory cortex in the vicinity of Heschl's gyrus, but have not determined the degree to which MMN reflects activation within primary auditory cortex (AI) itself. The present study, using moveable multichannel electrodes inserted acutely into superior temporal plane, demonstrates a significant contribution of AI to scalp-recorded MMN in the monkey, as reflected by greater response of AI to loud or soft clicks presented as deviants than to the same stimuli presented as repetitive standards. The MMN-like activity was localized primarily to supragranular laminae within AI. Thus, standard and deviant stimuli elicited similar degrees of initial, thalamocortical excitation. In contrast, responses within supragranular cortex were significantly larger to deviant stimuli than to standards. No MMN-like activity was detected in a limited number to passes that penetrated anterior and medial to AI. AI plays a well established role in the decoding of the acoustic properties of individual stimuli. The present study demonstrates that primary auditory cortex also plays an important role in processing the relationships between stimuli, and thus participates in cognitive, as well as purely sensory, processing of auditory information.

  3. Smoke-Free Workplace

    Science.gov (United States)

    1994-03-07

    34Environmental Smoke in the Workplace," June 1991 (d) Environmental Protection Agency (EPA) Report, "Respiratory Health Effects of Passive Smoking : Lung Cancer and...8217 (FTý, . kIrcferred to a, secondhand or passive smoke . Exhaled and/or sidestream smoke emitted from smokers and the burning of cigarettes, cigars, and...this - Urutti~. -- 2 / Each DoD Component thall:- 1. Control worker exposure to ETS by eliminatina smoking in the workplace. 2. Provide effective

  4. Towards the Education of the Future: Computational Thinking as a Generative Learning Mechanism

    Directory of Open Access Journals (Sweden)

    Eduardo SEGREDO

    2017-07-01

    Full Text Available The transformation of traditional education into a Sensitive, Manageable, Adaptable, Responsive and Timely (SMART education involves the comprehensive modernisation of all educational processes. For such a transformation, smart pedagogies are needed as a methodological issue while smart learning environments represent the technological issue, both having as an ultimate goal to cultivate smart learners. Smart learners need to develop 21st century skills so that they can become into smart citizens of our changing world. Technology and computers are an essential aspect for this modernisation, not only in terms of technological support for smart environments but also in terms of offering new methodologies for smart pedagogy and the development of smart skills. In this context, computational thinking appears as a promising mechanism to encourage core skills since it offers tools that fit learners’ interests and gives them the possibility to better understand the foundations of our ICT-based society and environments. In this work, we raise to make an effort to encourage the development of computational thinking as an opportunity to transform traditional pedagogies to smarter methodologies. We provide a general background about computational thinking and analyse the current state-of-the-art of smart education, emphasizing that there is a lack of smart methodologies which can support the training of 21st century smart skills. Finally, we provide —to those educators interested in pursuing the philosophy of smart education— information about initiatives devoted to the dissemination or promotion of computational thinking; existing tools or materials which support educators for the development of computational thinking among the students; and previous experiences and results about the application of computational thinking in educational environments.

  5. Cigarette smoke causes rapid lipid peroxidation of rat tracheal epithelium.

    OpenAIRE

    Churg, A.; Cherukupalli, K.

    1993-01-01

    Cigarette smoke-induced lipid peroxidation may be an important mechanism of smoke toxicity, but attempts to demonstrate peroxidation of pulmonary tissues after smoke exposure have yielded conflicting results. To examine this question, we exposed rat tracheal explants to whole smoke for 10 minutes followed by air recovery for periods up to 50 minutes (test), or to air alone (controls) and measured conjugated diene levels in the tissue. A dose-related increase in conjugated diene levels was see...

  6. Mechanisms of the Internally Generated Decadal-to-Multidecadal Variability in the Atlantic

    Science.gov (United States)

    Chen, Hua

    The thesis investigates the physical question of mechanisms of the Atlantic multidecadal variability (AMV) in a new way, using the weather noise forced interactive ensemble. It includes two distinct but closely related components. 1) Verification of the interactive ensemble strategy and justification for the noise forcing. In order to separate the noise from the SST forced response, the SST forced response in the atmospheric GCM (AGCM), forced by the SST from the coupled GCM (CGCM), has to be the same as in the CGCM. To be consistent, the noise should also be the same statistically in the CGCM and AGCM. Comparison of the CGCM and AGCM ensemble shows that these conditions are satisfied. Therefore, the interactive ensemble is an appropriate tool for the investigation, and the "noise" that is diagnosed and used as forcing is appropriate. Our results apply not just to the interactive ensemble, but also have broader implications important for the design of a wide range of climate modeling experiments. 2) Diagnosis of the multidecadal variability in the CGCM simulation. The diagnosis is done using the interactive ensemble CGCM, in which the heat flux, wind stress and fresh water flux weather noise components are applied at the ocean surface in different regions and in different combinations. The interactive ensemble simulations prove that the model's climate variability is predominantly forced by weather noise. The local weather noise forcing is found to be responsible for the SST variability in the Atlantic, with the noise heat flux and noise wind stress playing a critical role, while the noise fresh water flux has negligible impact. The North Atlantic Oscillation (NAO) pattern in the atmosphere, dominated by weather noise, forces the AMV 45-year mode through the noise heat flux and noise wind stress, with the former important in the eastern North Atlantic and the latter along the separated Gulf Stream. The noise wind stress forces the AMV 45-year mode through ocean

  7. Evaluation of the friction force generated by monocristalyne and policristalyne ceramic brackets in sliding mechanics

    Directory of Open Access Journals (Sweden)

    Roberta Ferreira Pimentel

    2013-02-01

    Full Text Available OBJECTIVE: To evaluate and compare "in vitro" the maximum friction force generated by three types of esthetic brackets, two types of polycrystalline conventional ceramic brackets (20/40 and InVu and one type of sapphire monocrystalline bracket (Radiance in dry and artificial saliva wet settings. Also, to evaluate the influence exerted by artificial saliva on the friction forces of those brackets. METHODS: Tests were performed in dry and artificial saliva wet setting (Oral Balance by using an EMIC DL 10000 testing machine, simulating a 2 mm slide of 0.019 x 0.025-in rectangular stainless steel wires over the pre-angulated and pre-torqued (right superior canine, Roth prescription, slot 0.022 x 0.030-in brackets (n = 18 for each bracket. In order to compare groups in dry and wet settings, the ANOVA was used. For comparisons related to the dry versus wet setting, the student t test was used for each group. RESULTS: The results showed that in the absence of saliva the Radiance monocrystalline brackets showed the highest friction coefficients, followed by the 20/40 and the InVu polycrystalline brackets. In tests with artificial saliva, the Radiance and the 20/40 brackets had statistically similar friction coefficients and both were greater than that presented by the InVu brackets. The artificial saliva did not change the maximum friction force of the Radiance brackets, but, for the others (20/40 and InVu, an increase of friction was observed in its presence. CONCLUSION: The InVu brackets showed, in the absence and in the presence of saliva, the lowest friction coefficient.OBJETIVO: avaliar e comparar in vitro as cargas máximas de atrito geradas por três tipos de braquetes estéticos, sendo dois deles cerâmicos policristalinos convencionais (20/40 e InVu e um monocristalino de safira (Radiance, em ambientes seco e umedecido por saliva artificial. Também avaliar a influência exercida pela saliva artificial sobre as cargas de atrito dos referidos

  8. Role of dissolved oxygen on the degradation mechanism of Reactive Green 19 and electricity generation in photocatalytic fuel cell.

    Science.gov (United States)

    Lee, Sin-Li; Ho, Li-Ngee; Ong, Soon-An; Wong, Yee-Shian; Voon, Chun-Hong; Khalik, Wan Fadhilah; Yusoff, Nik Athirah; Nordin, Noradiba

    2018-03-01

    In this study, a membraneless photocatalytic fuel cell with zinc oxide loaded carbon photoanode and platinum loaded carbon cathode was constructed to investigate the impact of dissolved oxygen on the mechanism of dye degradation and electricity generation of photocatalytic fuel cell. The photocatalytic fuel cell with high and low aeration rate, no aeration and nitrogen purged were investigated, respectively. The degradation rate of diazo dye Reactive Green 19 and the electricity generation was enhanced in photocatalytic fuel cell with higher dissolved oxygen concentration. However, the photocatalytic fuel cell was still able to perform 37% of decolorization in a slow rate (k = 0.033 h -1 ) under extremely low dissolved oxygen concentration (approximately 0.2 mg L -1 ) when nitrogen gas was introduced into the fuel cell throughout the 8 h. However, the change of the UV-Vis spectrum indicates that the intermediates of the dye could not be mineralized under insufficient dissolved oxygen level. In the aspect of electricity generation, the maximum short circuit current (0.0041 mA cm -2 ) and power density (0.00028 mW cm -2 ) of the air purged photocatalytic fuel cell was obviously higher than that with nitrogen purging (0.0015 mA cm -2 and 0.00008 mW cm -2 ). Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Aerossol bacteriano gerado por respiradores mecânicos: estudo comparativo Bacterial aerosol generated by mechanical ventilators: a comparative study

    Directory of Open Access Journals (Sweden)

    M. D'Agostino Dias

    1997-03-01

    Full Text Available Respiradores mecânicos emitem aerossóis que podem estar colonizados com bactérias. OBJETIVO. Estudar a contaminação ambiental gerada por respiradores, comparando-se dois siste-mas de umidificação. MÉTODOS. Realizaram-se 51 estudos, comparando-se a colonização dos aerossóis emitidos pela válvula expiratória dos aparelhos de ventilação mecânica, sendo em 31 com nebulizadores convencionais e em 20 com condensadores higroscópicos, em quinze minutos de observação. RESULTADOS. Houve emissão de bactérias para o ambiente, pela válvula expiratória, de 32,2% de respiradores equipados com sistema de nebulização convencional e de 5% com condensador (p = 0,0340. CONCLUSÃO. A umidificação da mistura gasosa com o uso de condensadores pode ser um meio eficiente de reduzir a contaminação bacteriana ambiental.Mechanical ventilators generate aerosol which may be bacterially colonized. PURPOSE - To determine the environmental contamination generated by ventilators with two different humidification techniques. METHODS - The study was done comparing the generation of bacterial colonized aerosol by the expiratory valve of mechanical respirators with conventional water nebulization or with hygroscopic condensator as the humidifier source during 15 minutes of observation. RESULTS - The aerosol got positive cultures in 32.2% of the conventional system and in 5% of the condensator system (p = 0.0340. CONCLUSION - We concluded that the humidification by the hygroscopic condensator may be an efficient way to reduce environmental bacterial contamination.

  10. Use of rheometry and {sup 1}H NMR spectroscopy for understanding the mechanisms behind the generation of coking pressure

    Energy Technology Data Exchange (ETDEWEB)

    Karen M. Steel; Miguel Castro Diaz; John W. Patrick; Colin E. Snape [Nottingham University, Nottingham (United Kingdom). Nottingham Fuel and Energy Centre, School of Chemical, Environmental and Mining Engineering

    2004-10-01

    The fluid phase which forms during carbonization of a range of coals was studied using rheometry and {sup 1}H NMR spectroscopy to study the mechanisms behind the generation of excessive wall pressures during coking. It is proposed that high coking pressures are generated for low volatile matter coals when the temperature of maximum fluidity (T{sub mf}) is {gt} 465{degree}C, the minimum complex viscosity ({eta}{asterisk}) is {gt} 10{sup 5} Pa s, the percentage of mobile 1H (fluid phase) is {lt} 40%, and the {sup 1}H mobility in the fluid phase is {lt} 65 {mu}s. It is suggested for these coals that the particles fuse to form a rigid network containing pockets of fluid material which have a low fluidity and do not link up. This arrangement could present an impermeable barrier for gas flow and force the gas to the coal side where it builds up in a diminishing region to a critical level, causing pressure on the walls. The magnitude of the pressure generated may be proportional to T{sub mf} and {eta}{asterisk} and inversely proportional to the percentage and mobility of mobile {sup 1}H. It was also found that a high volatile coal which formed a highly fluid phase over a broad temperature range gave rise to a significant coking pressure. In this case, it is proposed that the sheer expansion of the coal charge as it converts to gas and liquid phases is the reason for pressure on the oven walls. These proposals agree with current thinking on the generation of coking pressure. This work is based on the testing of only nine samples and further work is planned to gain a greater fundamental understanding of fluidity development from which models for predicting coking pressure and coke quality for coal blends may be developed. 20 refs., 10 figs., 5 tabs.

  11. Adolescent Smoking Trajectories

    Science.gov (United States)

    Bernat, Debra H.; Erickson, Darin J.; Widome, Rachel; Perry, Cheryl L.; Forster, Jean L.

    2009-01-01

    Purpose To identify distinct smoking trajectories during adolescence and assess how smoking-related factors relate to trajectory membership. Methods The sample includes 3637 youth from across the state of Minnesota. Measures include tobacco use, smoking behaviors of parents and friends, youth smoking-related attitudes and beliefs, and home smoking policies. A cohort-sequential design was used to identify smoking trajectories, including five cohorts of youth (ages 12–16) followed for 3 years. Results Six distinct trajectories of tobacco use were found: nonsmokers (54%), triers (17%), occasional users (10%), early established (7%), late established (8%), and decliners (4%). Several factors were associated with increased likelihood of being in a smoking trajectory group (vs. the nonsmoking group): parental smoking, friend smoking, greater perceptions of the number of adults and teenagers who smoke, and higher functional meaning of tobacco use. In contrast, higher perceived difficulty smoking in public places, negative perceptions of the tobacco industry, and home smoking policies were associated with less likelihood of being in one of the smoking trajectories (vs. the nonsmoking trajectory). Conclusions Adolescents exhibit diverse patterns of smoking during adolescence and tobacco-related influences were strong predictors of trajectory membership. PMID:18809130

  12. [Smoking and chronic autoimmune thyroiditis].

    Science.gov (United States)

    Buzoianu, Ioana Cristina; Arghir, Oana Cristina; Circo, E

    2010-01-01

    The chronic autoimmune thyroiditis are heterogeneous entities by the functional, lesional and evolutive point of view. Ethiopathogenic factors involved in chronic autoimmune thyroiditis are genetical factors, combines with environmental factors, hormonal factors, infectious factors etc. The exact role of smoking on the autoimmune mechanism is unclear, but smoking is known to have an antithyroid effect. Our study tries to estimate the influence of smoking on serum levels of antithyroid peroxidase antibodies and antithyroglobulin antibodies, in a group of patients with various clinical forms of chronic autoimmune thyroiditis. We studied a group consists of 310 patients with chronic autoimmune thyroiditis, hospitalised in the Endocrinology Department of Constanta County Hospital, between January 2006 - December 2009. We detected serum values of antithyroidperoxidase antibodies and antithyroglobulin antibodies of our patients. We also followed the age, sex and presence of smoking in our study group. For statistical processing of the data we use Student's t-test. In our study group 24.28% of patients were smokers. Serum levels of antithyroid peroxidase antibodies were significantly increased (p < 0.001) in the smokers patients, compared with the nonsmokers patients. Serum levels of antithyroglobulin antibodies were significantly increased (p < 0.01) in smokers patients, compared with those who were nonsmokers. Smoking increased the serum levels of antithyroid antibodies in patients with chronic autoimmune thyroiditis.

  13. Antibacterial mechanisms of a novel type picosecond laser-generated silver-titanium nanoparticles and their toxicity to human cells

    Directory of Open Access Journals (Sweden)

    Korshed P

    2017-12-01

    Full Text Available Peri Korshed,1 Lin Li,2 Zhu Liu,3 Aleksandr Mironov,4 Tao Wang1 1School of Biological Science, Faculty of Biology, Medicine and Health, 2Laser Processing Research Centre, School of Mechanical, Aerospace and Civil Engineering, 3School of Materials, 4Core Research Facilities, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK Abstract: In this study, we explored the antibacterial mechanisms for a novel type of Ag-TiO2 compound nanoparticles (NPs produced from an Ag-TiO2 alloy using a picosecond laser and evaluated the toxicity of the Ag-TiO2 NPs to a range of human cell types. Transmission electron microscopy was used to determine the morphology, shapes, and size distribution of the laser-generated Ag-TiO2 NPs. UV-visible spectrometer was used to confirm the shift of light absorbance of the NPs toward visible light wavelength. Results showed that the laser-generated Ag-TiO2 NPs had significant antibacterial activities against both Gram-negative and Gram-positive bacterial strains, including Escherichia coli, Pseudomonas aeruginosa, and the methicillin-resistant Staphylococcus aureus. Increased level of reactive oxygen species was produced by E. coli after exposure to the Ag-TiO2 NPs, which was accompanied with lipid peroxidation, glutathione depletion, disintegration of cell membrane and protein leakage, leading to the cell death. Five types of human cells originated from lung (A549, liver (HePG2, kidney (HEK293, endothelium cells (human coronary artery endothelial cells [hCAECs], and skin (human dermal fibroblast cells [HDFc] were used to evaluate the cytotoxicity of the laser-generated Ag-TiO2 NPs. A weak but statistically significant decrease in cell proliferation was observed for hCAECs, A549 and HDFc cells when co-cultured with 2.5 µg/mL or 20 µg/mL of the laser-generated Ag-TiO2 NPs for 48 hours. However, this effect was no longer apparent when a higher concentration of NPs (20 µg/mL was used after 72

  14. Air pollution and health implications of regional electricity transfer at generational centre and design of compensation mechanism

    Science.gov (United States)

    Relhan, Nemika

    damage into economic loss, the YOLL has been multiplied with Value of Life Year Lost (VOLY). VOLY has been derived from two approaches namely, the Gross Domestic Product (GDP) per capita i.e. using human capital approach and Value of Statistical Life (VOSL) i.e. using Willingness to Pay (WTP) approach derived from Indian revealed preference study. The morbidity damage has been estimated using cost of illness values available in the literature. A range of result has been presented depending on the CRF's used to estimates YOLL and morbidity and the values used to convert these health damages into monetary estimates. The study further suggests a broad framework of compensatory mechanism that includes 1) amount of compensation to be paid 2) mechanism to collect the compensation fund and 3) mechanism to compensate the affected communities. Both, curative and mitigative measures to protect the communities from the pollution generated in the power exporting region have been suggested.

  15. Posttraumatic stress and emotion dysregulation: Relationships with smoking to reduce negative affect and barriers to smoking cessation.

    Science.gov (United States)

    Short, Nicole A; Oglesby, Mary E; Raines, Amanda M; Zvolensky, Michael J; Schmidt, Norman B

    2015-08-01

    Many cigarette smokers have experienced a traumatic event, and elevated posttraumatic stress symptoms (PTSS) are associated with increased smoking levels. Previous research has found that elevated PTSS are associated with smoking to cope with negative affect, and it has been posited that perceptions of being unable to cope with the consequences of smoking cessation interfere with smoking cessation in this population. However, the mechanism of the relationship between PTSS and these smoking maintenance factors (i.e., smoking to reduce negative affect and barriers to cessation) has not been established. Emotion dysregulation is one potential mechanism as it is associated with PTSS as well as addictive behavior aimed at avoiding and reducing negative emotional states. We cross-sectionally tested the hypotheses that 1) PTSS and emotion dysregulation would be incrementally associated with smoking to reduce negative affect and barriers to cessation, and 2) that emotion dysregulation would mediate the relationships between PTSS, smoking to reduce negative affect, and barriers to cessation among a community sample of trauma-exposed individuals presenting for smoking cessation treatment (N=315). Results demonstrated that elevated PTSS were associated with increased smoking to reduce negative affect and barriers to cessation, and that emotion dysregulation mediated these relationships. These findings provide evidence of a mechanism between PTSS and psychological smoking maintenance factors, and suggest that emotion dysregulation may be a useful target for smoking cessation interventions among trauma-exposed individuals. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Measurements of smoke

    International Nuclear Information System (INIS)

    Bakker, F.P.; Geusebroek, M.; Kos, G.P.A.; Van Egmond, B.F.

    2005-02-01

    For Euromate measurements are performed at 21 December 2004, in order to characterize their new smoking chamber 'rookabri S+G2'. At location gas analysis and particle measurements are performed. A number of off-line sampled organic smoke trace compounds were analysed at our laboratory. Sampling and measurements were performed at different smoke levels with 0, 2, 4 and 6 smoking volunteers. The smoke-abri is a specially designed space for smokers in which the environment is cleared from tobacco smoke and odor [nl

  17. Sildenafil inhibits superoxide formation and prevents endothelial dysfunction in a mouse model of secondhand smoke induced erectile dysfunction.

    Science.gov (United States)

    Bivalacqua, Trinity J; Sussan, Thomas E; Gebska, Melina A; Strong, Travis D; Berkowitz, Dan E; Biswal, Shyam; Burnett, Arthur L; Champion, Hunter C

    2009-02-01

    We determined the effect of passive secondhand cigarette smoke on 1) erectile function in vivo, 2) molecular mechanisms involved in penile vascular function, and 3) erectile function and penile molecular signaling in the presence of phosphodiesterase type 5 inhibitor therapy. Four groups of mice were used, including group 1--controls, group 2--mice exposed to 3 weeks of secondhand smoke (5 hours per day for 5 days per week), group 3--control plus sildenafil (100 mg/kg per day) and group 4--smoke exposed plus sildenafil (100 mg/kg per day). Cavernous nerve electrical stimulation and intracavernous injection of acetylcholine were done to assess erectile function. Constitutive and inducible nitric oxide synthase activity, reactive oxygen species generation, nitrotyrosine formation and superoxide anion levels were assessed. Decreased erectile responses to cavernous nerve electrical stimulation and impaired endothelium dependent erectile responses to ACh in mice exposed to secondhand smoke were observed. Superoxide anion was increased in endothelial and corporeal smooth muscle cells of smoking mouse penises. In mice exposed to secondhand smoke constitutive nitric oxide synthase activity was decreased, and inducible nitric oxide synthase activity, reactive oxygen species generation and nitrotyrosine formation increased. Sildenafil therapy restored constitutive nitric oxide synthase activity in the penis of smoking mice, decreased inducible nitric oxide synthase activity, reactive oxygen species generation and nitrotyrosine formation, and improved erectile responses to cavernous nerve electrical stimulation and acetylcholine. Short-term exposure to secondhand smoke impairs erectile function through excessive penile reactive oxygen species signaling and inducible nitric oxide synthase activity. Decreased penile constitutive nitric oxide synthase activity may be attributable to the decreased endothelial nitric oxide synthase activity resulting from increased oxidative

  18. Endogenous Generation of Singlet Oxygen and Ozone in Human and Animal Tissues: Mechanisms, Biological Significance, and Influence of Dietary Components

    Directory of Open Access Journals (Sweden)

    Arnold N. Onyango

    2016-01-01

    Full Text Available Recent studies have shown that exposing antibodies or amino acids to singlet oxygen results in the formation of ozone (or an ozone-like oxidant and hydrogen peroxide and that human neutrophils produce both singlet oxygen and ozone during bacterial killing. There is also mounting evidence that endogenous singlet oxygen production may be a common occurrence in cells through various mechanisms. Thus, the ozone-producing combination of singlet oxygen and amino acids might be a common cellular occurrence. This paper reviews the potential pathways of formation of singlet oxygen and ozone in vivo and also proposes some new pathways for singlet oxygen formation. Physiological consequences of the endogenous formation of these oxidants in human tissues are discussed, as well as examples of how dietary factors may promote or inhibit their generation and activity.

  19. Immediate effects of cigar smoking on respiratory mechanics and exhaled biomarkers; differences between young smokers with mild asthma and otherwise healthy young smokers.

    Science.gov (United States)

    Lappas, Andreas S; Konstantinidi, Efstathia M; Tzortzi, Anna S; Tzavara, Chara K; Behrakis, Panagiotis K

    2016-01-01

    We aimed to investigate the immediate respiratory effects of cigar smoking(CS), among young smokers with and without mild asthma. Forty-seven young smokers (18-31years old, 29 males, average pack-years = 3.6 ± 2.8) were enrolled. Twenty-two were mild asthmatics(MA-subgroup) and the remaining 25 were otherwise healthy smokers(HS-subgroup). Exhaled carbon monoxide(eCO), multi-frequency respiratory system impedance(Z), resistance(R), reactance(X), frequency-dependence of resistance(fdr = R5Hz - R20Hz), resonant frequency(fres), reactance area(AX) and exhaled nitric oxide(FENO) were measured at the aforementioned sequence, before and immediately after 30 min of CS, or equal session in the smoking area while using a sham cigar(control group). Chi-square, student's t-tests, mixed linear models and Pearson correlation tests were used for the statistical analysis; level of significance was defined as p < 0.05. Immediately after CS, Z5Hz, R5Hz, R10Hz, R20Hz and eCO increased significantly in both subgroups(MA and HS). A greater increase was found for R20 in HS-subgroup. Fdr, fres and AX increased in MA, while decreased in HS. On the contrary, X10 decreased in MA and increased in HS, while X20 showed a greater decrease in MA. Changes in fdr, fres and AX were significantly correlated in both subgroups. No significant FENO alterations were detected in both subgroups. CS has immediate effects on pulmonary function. Mild asthma predisposes to higher increase of peripheral resistance(increased fdr). In otherwise healthy smokers, central resistance(R20Hz) is more affected. FENO levels are not significantly affected by CS.

  20. Young Adult Smoking Behavior

    Science.gov (United States)

    Ling, Pamela M.; Neilands, Torsten B.; Glantz, Stanton A.

    2009-01-01

    Background Young adults have the highest smoking rate of any age group in the U.S., and new strategies to decrease young adult smoking are needed. The objective of the current study was to identify psychographic and demographic factors associated with current smoking and quitting behaviors among young adults. Methods Attitudes, social groups, and self-descriptors, including supporting action against the tobacco industry, advertising receptivity, depression, alcohol use, and other factors associated with smoking were tested for associations with smoking behaviors in a 2005 cross-sectional survey of 1528 young adults (aged 18–25 years) from a web-enabled panel. Analyses were conducted in 2007. Results Being older was associated with current smoking, whereas having some higher education and being African American or Hispanic were negatively associated with smoking. Supporting action against the tobacco industry was negatively associated with smoking (AOR=0.34 [95% CI=0.22, 0.52]). Perceived usefulness of smoking, exposure to smokers, increased perceived smoking prevalence, receptivity to tobacco advertising, binge drinking, and exposure to tobacco advertising in bars and clubs were associated with smoking. Supporting action against the tobacco industry was associated with intentions to quit smoking (AOR= 4.43 [95% CI=2.18, 8.60]). Conclusions Young adults are vulnerable to tobacco-industry advertising. Media campaigns that denormalize the tobacco industry and appeal to young adults appear to be a powerful intervention to decrease young adult smoking. PMID:19269128

  1. Exposure to teachers smoking and adolescent smoking behaviour

    DEFF Research Database (Denmark)

    Poulsen, L H; Osler, M; Roberts, C

    2002-01-01

    To determine whether adolescent smoking behaviour is associated with their perceived exposure to teachers or other pupils smoking at school, after adjustment for exposure to smoking at home, in school, and best friends smoking.......To determine whether adolescent smoking behaviour is associated with their perceived exposure to teachers or other pupils smoking at school, after adjustment for exposure to smoking at home, in school, and best friends smoking....

  2. Spatiotemporal impacts of LULC changes on hydrology from the perspective of runoff generation mechanism using SWAT model with evolving parameters

    Science.gov (United States)

    Li, Y.; Chang, J.; Luo, L.

    2017-12-01

    It is of great importance for water resources management to model the truly hydrological process under changing environment, especially under significant changes of underlying surfaces like the Wei River Bain (WRB) where the subsurface hydrology is highly influenced by human activities, and to systematically investigate the interactions among LULC change, streamflow variation and changes in runoff generation process. Therefore, we proposed the idea of evolving parameters in hydrological model (SWAT) to reflect the changes in physical environment with different LULC conditions. Then with these evolving parameters, the spatiotemporal impacts of LULC changes on streamflow were quantified, and qualitative analysis was conducted to further explore how LULC changes affect the streamflow from the perspective of runoff generation mechanism. Results indicate the following: 1) evolving parameter calibration is not only effective but necessary to ensure the validity of the model when dealing with significant changes in underlying surfaces due to human activities. 2) compared to the baseline period, the streamflow in wet seasons increased in the 1990s but decreased in the 2000s. While at yearly and dry seasonal scales, the streamflow decreased in both two decades; 3) the expansion of cropland is the major contributor to the reduction of surface water component, thus causing the decline in streamflow at yearly and dry seasonal scales. While compared to the 1990s, the expansions of woodland in the middle stream and grassland in the downstream are the main stressors that increased the soil water component, thus leading to the more decline of the streamflow in the 2000s.

  3. Use of varenicline for 4 weeks before quitting smoking: decrease in ad lib smoking and increase in smoking cessation rates.

    Science.gov (United States)

    Hajek, Peter; McRobbie, Hayden J; Myers, Katie E; Stapleton, John; Dhanji, Al-Rehan

    2011-04-25

    The use of varenicline tartrate alleviates postquit withdrawal discomfort, but it also seems to reduce the "reward" associated with smoking. The current treatment schedule, which commences 1 week before quitting, relies primarily on the first mechanism. We set out to determine whether increasing the prequit medication period renders cigarettes less satisfying and facilitates quitting. One hundred one smokers attending a stop-smoking clinic in London, United Kingdom, were randomly allocated to receive varenicline for 4 weeks before the target quit date (TQD) or to receive placebo for 3 weeks before the TQD, followed by varenicline for 1 week before the TQD. In both groups, standard varenicline treatment was given for 3 months after the TQD. Measures included smoking satisfaction and smoke intake before quitting, urges to smoke and withdrawal discomfort after quitting, and sustained abstinence from the TQD to 3 months. Varenicline preloading reduced prequit enjoyment of smoking (P = .004) and smoke intake (P lib smoking and enhance 12-week quit rates. Current treatment schedules may lead to suboptimal treatment results. Trials with longer follow-up periods are needed to corroborate these findings. Trial Registration clinicaltrials.gov Identifier: NCT00789074.

  4. Teenagers and Smoking.

    Science.gov (United States)

    PTA Today, 1986

    1986-01-01

    The Coalition on Smoking OR Health was established to coordinate education programs to discourage young people from smoking. Projects that could be undertaken by parent associations are suggested. (MT)

  5. Smoking and asthma

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000504.htm Smoking and asthma To use the sharing features on ... your allergies or asthma worse are called triggers. Smoking is a trigger for many people who have ...

  6. Allegheny County Smoking Rates

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Smoking rates for each Census Tract in Allegheny County were produced for the study “Developing small-area predictions for smoking and obesity prevalence in the...

  7. [Smoking and stroke].

    Science.gov (United States)

    Hashimoto, Yoichiro

    2011-05-01

    Cigarette smoking is a risk factor for the brain infarction (lacunar and atherothrombotic brain infarction) and subarachnoid hemorrhage. Not only active smoking but also passive smoking and smokeless tobacco products pose a risk. The risk after smoking cessation for 5-10 years is equal to that faced by a non-smoker. Many patients continue smoking even after an attack of stroke; therefore, support measures to enforce nonsmoking are required in this high-risk population. We offer nonsmoking support using the 5A approach, and assess the nonsmoking stage (precontemplation, contemplation, preparation, action, and maintenance). We also administer medical therapy for smoking cessation when the patients find it difficult to quit smoking on their own accord. Nicotine dependency needs a follow-up like that required for other risk factors in the primary and secondary prevention of the stroke because smoking is a chronic disease that tends to recur.

  8. Antibody-induced generation of reactive oxygen radicals by brain macrophages in canine distemper encephalitis: a mechanism for bystander demyelination.

    Science.gov (United States)

    Griot, C; Bürge, T; Vandevelde, M; Peterhans, E

    1989-01-01

    The mechanism of inflammatory demyelination in canine distemper encephalitis (CDE) is uncertain but macrophages are thought to play an important effector role in this lesion. Serum and cerebrospinal fluid (CSF), containing anti-canine distemper virus and anti-myelin antibodies from dogs with CDE were tested for their ability to generate reactive oxygen species (ROS) in macrophages in primary dog brain cell cultures using a chemiluminescence (CL) assay. The majority of serum samples and several CSF samples from animals with inflammatory demyelination elicited a CL signal in infected dog brain cell cultures. In contrast, none of these samples induced a positive response in uninfected cultures which contained large numbers of myelin antigen-presenting cells, although defined anti-myelin antibodies lead to a marked secretion of ROS in this system. It was concluded that antiviral antibody-induced secretion of ROS, known to be highly toxic for brain tissue, may play an important role in white matter damage in inflammatory lesions supporting a previous hypothesis of bystander demyelination in CDE. No evidence was found for a similar antibody-dependent cellular cytotoxicity-like mechanism mediated by anti-myelin antibodies in CDE, which does not support the concept of autoimmunity in this disease.

  9. A Study on Tooling and Its Effect on Heat Generation and Mechanical Properties of Welded Joints in Friction Stir Welding

    Science.gov (United States)

    Tikader, Sujoy; Biswas, Pankaj; Puri, Asit Baran

    2018-04-01

    Friction stir welding (FSW) has been the most attracting solid state welding process as it serves numerous advantages like good mechanical, metallurgical properties etc. Non weldable aluminium alloys like 5XXX, 7XXX series can be simply joined by this process. In this present study a mathematical model has been developed and experiments were successfully performed to evaluate mechanical properties of FSW on similar aluminium alloys i.e. AA1100 for different process parameters and mainly two kind of tool geometry (straight cylindrical and conical or cylindrical tapered shaped pin with flat shoulder). Tensile strength and micro hardness for different process parameters are reported of the welded plate sample. It was noticed that in FSW of similar alloy with tool made of SS-310 tool steel, friction is the major contributor for the heat generation. It was seen that tool geometry, tool rotational speed, plunging force by the tool and traverse speed have significant effect on tensile strength and hardness of friction stir welded joints.

  10. The Performance Evaluation of Horizontal Axis Wind Turbine Torque and Mechanical Power Generation Affected by the Number of Blade

    Directory of Open Access Journals (Sweden)

    Tan Rodney H. G.

    2016-01-01

    Full Text Available This paper presents the evaluation of horizontal axis wind turbine torque and mechanical power generation and its relation to the number of blades at a given wind speed. The relationship of wind turbine rotational frequency, tip speed, minimum wind speed, mechanical power and torque related to the number of blades are derived. The purpose of this study is to determine the wind energy extraction efficiency achieved for every increment of blade number. Effective factor is introduced to interpret the effectiveness of the wind turbine extracting wind energy below and above the minimum wind speed for a given number of blades. Improve factor is introduced to indicate the improvement achieved for every increment of blades. The evaluation was performance with wind turbine from 1 to 6 blades. The evaluation results shows that the higher the number of blades the lower the minimum wind speed to achieve unity effective factor. High improve factors are achieved between 1 to 2 and 2 to 3 blades increment. It contributes to better understanding and determination for the choice of the number of blades for wind turbine design.

  11. Relationship between Audiometric Slope and Tinnitus Pitch in Tinnitus Patients: Insights into the Mechanisms of Tinnitus Generation

    Science.gov (United States)

    Schecklmann, Martin; Vielsmeier, Veronika; Steffens, Thomas; Landgrebe, Michael; Langguth, Berthold; Kleinjung, Tobias

    2012-01-01

    Background Different mechanisms have been proposed to be involved in tinnitus generation, among them reduced lateral inhibition and homeostatic plasticity. On a perceptual level these different mechanisms should be reflected by the relationship between the individual audiometric slope and the perceived tinnitus pitch. Whereas some studies found the tinnitus pitch corresponding to the maximum hearing loss, others stressed the relevance of the edge frequency. This study investigates the relationship between tinnitus pitch and audiometric slope in a large sample. Methodology This retrospective observational study analyzed 286 patients. The matched tinnitus pitch was compared to the frequency of maximum hearing loss and the edge of the audiogram (steepest hearing loss) by t-tests and correlation coefficients. These analyses were performed for the whole group and for sub-groups (uni- vs. bilateral (117 vs. 338 ears), pure-tone vs. narrow-band (340 vs. 115 ears), and low and high audiometric slope (114 vs. 113 ears)). Findings For the right ear, tinnitus pitch was in the same range and correlated significantly with the frequency of maximum hearing loss, but differed from and did not correlate with the edge frequency. For the left ear, similar results were found but the correlation between tinnitus pitch and maximum hearing loss did not reach significance. Sub-group analyses (bi- and unilateral, tinnitus character, slope steepness) revealed identical results except for the sub-group with high audiometric slope which revealed a higher frequency of maximum hearing loss as compared to the tinnitus pitch. Conclusion The study-results confirm a relationship between tinnitus pitch and maximum hearing loss but not to the edge frequency, suggesting that tinnitus is rather a fill-in-phenomenon resulting from homeostatic mechanisms, than the result of deficient lateral inhibition. Sub-group analyses suggest that audiometric steepness and the side of affected ear affect this

  12. Relationship between Audiometric slope and tinnitus pitch in tinnitus patients: insights into the mechanisms of tinnitus generation.

    Directory of Open Access Journals (Sweden)

    Martin Schecklmann

    Full Text Available BACKGROUND: Different mechanisms have been proposed to be involved in tinnitus generation, among them reduced lateral inhibition and homeostatic plasticity. On a perceptual level these different mechanisms should be reflected by the relationship between the individual audiometric slope and the perceived tinnitus pitch. Whereas some studies found the tinnitus pitch corresponding to the maximum hearing loss, others stressed the relevance of the edge frequency. This study investigates the relationship between tinnitus pitch and audiometric slope in a large sample. METHODOLOGY: This retrospective observational study analyzed 286 patients. The matched tinnitus pitch was compared to the frequency of maximum hearing loss and the edge of the audiogram (steepest hearing loss by t-tests and correlation coefficients. These analyses were performed for the whole group and for sub-groups (uni- vs. bilateral (117 vs. 338 ears, pure-tone vs. narrow-band (340 vs. 115 ears, and low and high audiometric slope (114 vs. 113 ears. FINDINGS: For the right ear, tinnitus pitch was in the same range and correlated significantly with the frequency of maximum hearing loss, but differed from and did not correlate with the edge frequency. For the left ear, similar results were found but the correlation between tinnitus pitch and maximum hearing loss did not reach significance. Sub-group analyses (bi- and unilateral, tinnitus character, slope steepness revealed identical results except for the sub-group with high audiometric slope which revealed a higher frequency of maximum hearing loss as compared to the tinnitus pitch. CONCLUSION: The study-results confirm a relationship between tinnitus pitch and maximum hearing loss but not to the edge frequency, suggesting that tinnitus is rather a fill-in-phenomenon resulting from homeostatic mechanisms, than the result of deficient lateral inhibition. Sub-group analyses suggest that audiometric steepness and the side of affected ear

  13. Nanoscale chemical and mechanical characterization of thin films:sum frequency generation (SFG) vibrational spectroscopy at buriedinterfaces

    Energy Technology Data Exchange (ETDEWEB)

    Kweskin, Sasha Joseph [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    Sum frequency generation (SFG) surface vibrational spectroscopy was used to characterize interfaces pertinent to current surface engineering applications, such as thin film polymers and novel catalysts. An array of advanced surface science techniques like scanning probe microscopy (SPM), x-ray photoelectron spectroscopy (XPS), gas chromatography (GC) and electron microscopy were used to obtain experimental measurements complementary to SFG data elucidating polymer and catalyst surface composition, surface structure, and surface mechanical behavior. Experiments reported in this dissertation concentrate on three fundamental questions: (1) How does the interfacial molecular structure differ from that of the bulk in real world applications? (2) How do differences in chemical environment affect interface composition or conformation? (3) How do these changes correlate to properties such as mechanical or catalytic performance? The density, surface energy and bonding at a solid interface dramatically alter the polymer configuration, physics and mechanical properties such as surface glass transition, adhesion and hardness. The enhanced sensitivity of SFG at the buried interface is applied to three systems: a series of acrylates under compression, the compositions and segregation behavior of binary polymer polyolefin blends, and the changes in surface structure of a hydrogel as a function of hydration. In addition, a catalytically active thin film of polymer coated nanoparticles is investigated to evaluate the efficacy of SFG to provide in situ information for catalytic reactions involving small mass adsorption and/or product development. Through the use of SFG, in situ total internal reflection (TIR) was used to increase the sensitivity of SFG and provide the necessary specificity to investigate interfaces of thin polymer films and nanostructures previously considered unfeasible. The dynamic nature of thin film surfaces is examined and it is found that the non

  14. Ionization smoke detector and alarm system

    International Nuclear Information System (INIS)

    1974-01-01

    An ionization smoke detector particularly suited to residential use is disclosed. The detector is battery-operated and is connected with a non-latching, pulsating alarm circuit. The detector has a sensing chamber formed by a perforated metallic shell and an electrode within which an insulated radiation source is centrally positioned to generate an ionization current for detecting smoke or other similar aerosols. The alarm circuit provides a pulsating alarm signal when smoke levels above a pre-determined value are sensed. The alarm circuit also includes a low voltage detection circuit for sounding the alarm when the end of useful battery life is approaching. (Auth.)

  15. Harnessing Facebook for Smoking Reduction and Cessation Interventions: Facebook User Engagement and Social Support Predict Smoking Reduction

    Science.gov (United States)

    Marsch, Lisa A; Brunette, Mary F; Dallery, Jesse

    2017-01-01

    Background Social media technologies offer a novel opportunity for scalable health interventions that can facilitate user engagement and social support, which in turn may reinforce positive processes for behavior change. Objective By using principles from health communication and social support literature, we implemented a Facebook group–based intervention that targeted smoking reduction and cessation. This study hypothesized that participants’ engagement with and perceived social support from our Facebook group intervention would predict smoking reduction. Methods We recruited 16 regular smokers who live in the United States and who were motivated in quitting smoking at screening. We promoted message exposure as well as engagement and social support systems throughout the intervention. For message exposure, we posted prevalidated, antismoking messages (such as national antismoking campaigns) on our smoking reduction and cessation Facebook group. For engagement and social support systems, we delivered a high degree of engagement and social support systems during the second and third week of the intervention and a low degree of engagement and social support systems during the first and fourth week. A total of six surveys were conducted via Amazon Mechanical Turk (MTurk) at baseline on a weekly basis and at a 2-week follow-up. Results Of the total 16 participants, most were female (n=13, 81%), white (n=15, 94%), and between 25 and 50 years of age (mean 34.75, SD 8.15). There was no study attrition throughout the 6-time-point baseline, weekly, and follow-up surveys. We generated Facebook engagement and social support composite scores (mean 19.19, SD 24.35) by combining the number of likes each participant received and the number of comments or wall posts each participant posted on our smoking reduction and cessation Facebook group during the intervention period. The primary outcome was smoking reduction in the past 7 days measured at baseline and at the two

  16. Harnessing Facebook for Smoking Reduction and Cessation Interventions: Facebook User Engagement and Social Support Predict Smoking Reduction.

    Science.gov (United States)

    Kim, Sunny Jung; Marsch, Lisa A; Brunette, Mary F; Dallery, Jesse

    2017-05-23

    Social media technologies offer a novel opportunity for scalable health interventions that can facilitate user engagement and social support, which in turn may reinforce positive processes for behavior change. By using principles from health communication and social support literature, we implemented a Facebook group-based intervention that targeted smoking reduction and cessation. This study hypothesized that participants' engagement with and perceived social support from our Facebook group intervention would predict smoking reduction. We recruited 16 regular smokers who live in the United States and who were motivated in quitting smoking at screening. We promoted message exposure as well as engagement and social support systems throughout the intervention. For message exposure, we posted prevalidated, antismoking messages (such as national antismoking campaigns) on our smoking reduction and cessation Facebook group. For engagement and social support systems, we delivered a high degree of engagement and social support systems during the second and third week of the intervention and a low degree of engagement and social support systems during the first and fourth week. A total of six surveys were conducted via Amazon Mechanical Turk (MTurk) at baseline on a weekly basis and at a 2-week follow-up. Of the total 16 participants, most were female (n=13, 81%), white (n=15, 94%), and between 25 and 50 years of age (mean 34.75, SD 8.15). There was no study attrition throughout the 6-time-point baseline, weekly, and follow-up surveys. We generated Facebook engagement and social support composite scores (mean 19.19, SD 24.35) by combining the number of likes each participant received and the number of comments or wall posts each participant posted on our smoking reduction and cessation Facebook group during the intervention period. The primary outcome was smoking reduction in the past 7 days measured at baseline and at the two-week follow-up. Compared with the baseline

  17. Economics of smoking cessation

    OpenAIRE

    Parrott, S.; Godfrey, C.

    2004-01-01

    Smoking imposes a huge economic burden on society— currently up to 15% of total healthcare costs in developed countries. Smoking cessation can save years of life, at a very low cost compared with alternative interventions. This chapter reviews some of the economic aspects of smoking cessation.

  18. Wildfire Smoke Emissions webinar

    Science.gov (United States)

    This webinar presented by Wayne Cascio will highlight updates to the Wildfire Smoke Guide, as well as the Smoke Sense app, which is a mobile application that gets air quality information to people impacted by wildfire smoke, and helps those affected learn

  19. Mechanism

    Directory of Open Access Journals (Sweden)

    Yao Yu

    2010-01-01

    Full Text Available The kinematics analysis method of a novel 3-DOF wind tunnel mechanism based on cable-driven parallel mechanism is provided. Rodrigues' parameters are applied to express the transformation matrix of the wire-driven mechanism in the paper. The analytical forward kinematics model is described as three quadratic equations using three Rodridgues' parameters based on the fundamental theory of parallel mechanism. Elimination method is used to remove two of the variables, so that an eighth-order polynomial with one variable is derived. From the equation, the eight sets of Rodridgues' parameters and corresponding Euler angles for the forward kinematical problem can be obtained. In the end, numerical example of both forward and inverse kinematics is included to demonstrate the presented forward-kinematics solution method. The numerical results show that the method for the position analysis of this mechanism is effective.

  20. Promoting smoking cessation among parents: Effects on smoking-related cognitions and smoking initiation in children

    NARCIS (Netherlands)

    Schuck, K.; Otten, R.; Kleinjan, M.; Bricker, J.B.; Engels, R.C.M.E.

    2015-01-01

    Background Parental smoking is associated with an increased risk of smoking among youth. Epidemiological research has shown that parental smoking cessation can attenuate this risk. This study examined whether telephone counselling for parents and subsequent parental smoking cessation affect

  1. Effects of Smoking on Pegylated Interferon alpha 2a and First Generation Protease Inhibitor-based Antiviral Therapy in Naïve Patients Infected with Hepatitis C Virus Genotype 1.

    Science.gov (United States)

    Zimmermann, Tim; Hueppe, Dietrich; Mauss, Stefan; Buggisch, Peter; Pfeiffer-Vornkahl, Heike; Grimm, Daniel; Galle, Peter R; Alshuth, Ulrich

    2016-03-01

    Smoking has multiple effects on factors influencing hepatitis C and antiviral therapy, including lipid metabolism, fibrosis, platelet count and adherence aspects. The aim of this analysis was to determine the impact of smoking on hepatitis C virus antiviral therapy. Data of two cohorts of an observational multicenter study including therapy-naïve patients infected with genotype 1 hepatitis C virus (HCV) treated with dual antiviral therapy (n=7,796) with pegylated interferon alpha 2a in combination with ribavirin, or triple antiviral therapy (n=1,122) containing telaprevir or boceprevir, were analysed. In the univariate matched pair analysis of dual antiviral therapy patients (n=584), smoking was significantly associated with lower sustained viral response rates (p=0.026, OR 0.69 CI: 0.50 - 0.96). The effect of smoking on sustained viral response remained significant (p=0.028, OR 0.67 CI: 0.47 - 0.96) in the multivariate analysis when adjusting for all other baseline parameters with a significant association in the univariate analysis, i.e. diabetes, fibrosis, body mass index, transaminases and baseline viral load. Under protease inhibitors the influence of smoking on virological response did not arise. Smoking has a negative impact on antiviral therapy in naïve patients infected with HCV genotype 1 independently of age, gender, history of drug use or alcoholic liver disease. The effects of smoking might be overcome by the new antiviral agents.

  2. The case for investigating social context in laboratory studies of smoking.

    Science.gov (United States)

    Dimoff, John D; Sayette, Michael A

    2017-03-01

    With increasing frequency, addiction is conceived of as a brain disease, and such accounts seem especially pertinent with regard to the rapid delivery of nicotine to the brain via cigarette smoke. Moreover, drug administration trials (cigarette puffs) suggest that the behavior of smoking becomes automatized, with individuals developing prototypical approaches to smoking a cigarette. Compared with presumably more social activities, such as drinking alcohol, there may be little opportunity for social processes to influence smoking behavior. However, survey research examining smoking motivation often reveals a broadly defined 'social' factor and field research suggests that social context does influence smoking. We posit that laboratory smoking research has largely ignored social contextual factors that may help to understand better the precise mechanisms underlying smoking behavior and smoking motivation. We reviewed laboratory studies examining the effect of social context (operationalized as modeling) on smoking behavior. Studies were identified by searching PsychInfo and Medline using the following keywords: smoking, nicotine, tobacco, cigarette, consumption, topography, puff, smoking behavior, cigarettes smoked, modeling, imitation, social context, social influence and peer pressure. The reference and citation lists of these studies were then searched to identify additional studies. Few laboratory smoking studies target social context. Those few studies indicate that smoking behavior can be influenced by the presence of others. There is also some evidence that social context influences the effects of smoking as well as processes related to self-perception and self-regulation that reinforce smoking and hamper smoking cessation efforts. © 2016 Society for the Study of Addiction.

  3. Assessment of an in vitro whole cigarette smoke exposure system: The Borgwaldt RM20S 8-syringe smoking machine

    Directory of Open Access Journals (Sweden)

    McAughey John

    2011-08-01

    Full Text Available Abstract Background There have been many recent developments of in vitro cigarette smoke systems closely replicating in vivo exposures. The Borgwaldt RM20S smoking machine (RM20S enables the serial dilution and delivery of cigarette smoke to exposure chambers for in vitro analyses. In this study we have demonstrated reliability and robustness testing of the RM20S in delivering smoke to in vitro cultures using an in-house designed whole smoke exposure chamber. Results The syringe precision and accuracy of smoke dose generated by the RM20S was assessed using a methane gas standard and resulted in a repeatability error of ≤9%. Differential electrical mobility particle spectrometry (DMS measured smoke particles generated from reference 3R4F cigarettes at points along the RM20S. 53% ± 5.9% of particles by mass reached the chamber, the remainder deposited in the syringe or connecting tubing and ~16% deposited in the chamber. Spectrofluorometric quantification of particle deposition within chambers indicated a positive correlation between smoke concentration and particle deposition. In vitro air-liquid interface (ALI cultures (H292 lung epithelial cells, exposed to whole smoke (1:60 dilution (smoke:air, equivalent to ~5 μg/cm2 demonstrated uniform smoke delivery within the chamber. Conclusions These results suggest this smoke exposure system is a reliable and repeatable method of generating and exposing ALI in vitro cultures to cigarette smoke. This system will enable the evaluation of future tobacco products and individual components of cigarette smoke and may be used as an alternative in vitro tool for evaluating other aerosols and gaseous mixtures such as air pollutants, inhaled pharmaceuticals and cosmetics.

  4. Cigarette Smoke Alters the Hematopoietic Stem Cell Niche

    Directory of Open Access Journals (Sweden)

    Robert W. Siggins

    2014-02-01

    Full Text Available Effects of tobacco smoke on hematologic derangements have received little attention. This study employed a mouse model of cigarette smoke exposure to explore the effects on bone marrow niche function. While lung cancer is the most widely studied consequence of tobacco smoke exposure, other malignancies, including leukemia, are associated with tobacco smoke exposure. Animals received cigarette smoke exposure for 6 h/day, 5 days/week for 9 months. Results reveal that the hematopoietic stem and progenitor cell (HSPC pool size is reduced by cigarette smoke exposure. We next examined the effect of cigarette smoke exposure on one supporting cell type of the niche, the mesenchymal stromal cells (MSCs. Smoke exposure decreased the number of MSCs. Transplantation of naïve HSPCs into irradiated mice with cigarette smoke exposure yielded fewer numbers of engrafted HSPCs. This result suggests that smoke-exposed mice possess dysfunctional niches, resulting in abnormal hematopoiesis. Co-culture experiments using MSCs isolated from control or cigarette smoke-exposed mice with naïve HSPCs in vitro showed that MSCs from cigarette smoke-exposed mice generated marked expansion of naïve HSPCs. These data show that cigarette smoke exposure decreases in vivo MSC and HSC number and also increases pro-proliferative gene expression by cigarette smoke-exposed MSCs, which may stimulate HSPC expansion. These results of this investigation are clinically relevant to both bone marrow donors with a history of smoking and bone marrow transplant (BMT recipients with a history of smoking.

  5. Sulfate-dependent Anaerobic Oxidation of Methane as a Generation Mechanism for Calcite Cap Rock in Gulf Coast Salt Domes

    Science.gov (United States)

    Caesar, K. H.; Kyle, R.; Lyons, T. W.; Loyd, S. J.

    2015-12-01

    Gulf Coast salt domes, specifically their calcite cap rocks, have been widely recognized for their association with significant reserves of crude oil and natural gas. However, the specific microbial reactions that facilitate the precipitation of these cap rocks are still largely unknown. Insight into the mineralization mechanism(s) can be obtained from the specific geochemical signatures recorded in these structures. Gulf Coast cap rocks contain carbonate and sulfur minerals that exhibit variable carbon (d13C) and sulfur isotope (δ34S) signatures. Calcite d13C values are isotopically depleted and show a large range of values from -1 to -52‰, reflecting a mixture of various carbon sources including a substantial methane component. These depleted carbon isotope compositions combined with the presence of abundant sulfide minerals in cap rocks have led to interpretations that invoke microbial sulfate reduction as an important carbonate mineral-yielding process in salt dome environments. Sulfur isotope data from carbonate-associated sulfate (CAS: trace sulfate incorporated within the carbonate mineral crystal lattice) provide a more direct proxy for aqueous sulfate in salt dome systems and may provide a means to directly fingerprint ancient sulfate reduction. We find CAS sulfur isotope compositions (δ34SCAS) significantly greater than those of the precursor Jurassic sulfate-salt deposits (which exhibit δ34S values of ~ +15‰). This implies that cap rock carbonate generation occurred via microbial sulfate reduction under closed-system conditions. The co-occurrence of depleted carbonate d13C values (production of alkalinity. Collectively, these data shed new light on a potential hotspot of microbial activity in the deep biosphere.

  6. EEG activities during elicited sleep onset REM and NREM periods reflect different mechanisms of dream generation. Electroencephalograms. Rapid eye movement.

    Science.gov (United States)

    Takeuchi, Tomoka; Ogilvie, Robert D; Murphy, Timothy I; Ferrelli, Anthony V

    2003-02-01

    To be the first to compare EEG power spectra during sleep onset REM periods (SOREMP) and sleep onset NREM periods (NREMP) in normal individuals and relate this to dream appearance processes underlying these different types of sleep periods. Eight healthy undergraduates spent 7 consecutive nights in the sleep lab including 4 nights for SOREMP elicitation using the Sleep Interruption Technique. This enabled us to control preceding sleep processes between SOREMP and NREMP. EEG power spectra when participants did and did not report 'dreams' were compared between both types of sleep. Sleep stages, subjective measurements including dream property scores, sleepiness, mood, and tiredness after awakenings were also examined to determine their consistency with EEG findings. Increased alpha EEG activities (11.72-13.67 Hz) observed mainly in the central area were related to the absence of SOREMP dreams and appearance of NREMP dreams. Analyses of sleep stages combining two studies (16 participants) also supported the Fast Fourier Transform findings, showing that when dreams were reported there were decreased amounts of stage 2 and increased stage REM in SOREMP and increased stage W in NREMP. SOREMP dreams were more bizarre than NREMP dreams. Participants felt more tired after SOREMP with dreams than without dreams, while the opposite was observed after NREMP episodes. EEG power spectra patterns reflected different physiological mechanisms underlying generation of SOREMP and NREMP dreams. The same relationships were also reflected by sleep stage analyses as well as subjective measurements including dream properties and tiredness obtained after awakenings. This study not only supports the hypothesized relationships between REM mechanisms and REM dreams as well as arousal processes and NREM dreams, it also provides a new perspective to dream research due to its unique techniques to awaken participants and collect REM dreams during experimentally induced SOREMP.

  7. Modernization perspectives of the Sao Paulo State sugarcane sector through the clean development mechanism and potential carbon credits generation

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Suani Teixeira; Lora, Beatriz Acquaro [Brazilian Reference Center on Biomass (CENBIO/USP), SP (Brazil)], Emails: suani@iee.usp.br, blora@iee.usp.br

    2009-07-01

    The world-wide necessity of greenhouse gases mitigation and the intergovernmental mobilization to reach the objectives established by the United Nations Framework on Climate Change (UNFCCC) has opened space for the renewable energy increase in the world's energy matrix. In Brazil, the solid sugarcane industry currently develops business in the scope of the clean development mechanism (CDM) under the Kyoto's Protocol, by means of 18 biomass-based projects, with renewable energy generation through bagasse cogeneration at 20 Sao Paulo State's sugarcane production units. The projects activity's consists of increasing the efficiency in the bagasse cogeneration facilities, qualifying the units to sell surplus electricity to the national grid, avoiding the dispatch of the same amount of energy produced by fossil-fuelled thermal plants to that grid. The reduced emissions are measured in carbon equivalent and can be converted into negotiable credits. The objective of this study was to build a 'state of art' scenario, calculating the potential emissions reduction through CDM projects for the sugarcane sector of Sao Paulo State, in which we consider the adherence of all the production units of the State to the CDM projects. The technological parameters used to elaborate the scenario were provided by the Sao Paulo State Government Bioenergy Special Commission and the baseline factor used of 0,268 tCO{sub 2}e/MWh was the adopted by the CDM projects in operation in the State. The sugarcane database for the calculations was the production ranking provided by UNICA for the 2006/2007 season. In the most conservative scenario (40 bar bagasse) 131 units could generate 607 MWm of surplus power avoiding the emission of 1.404.593 tCO{sub 2}e/year. For the 92 bar (bagasse and straw) scenario, the units could generate 3.055 MWm of surplus power avoiding 12.199.443 tCO{sub 2}e/year. (author)

  8. Worldwide effort against smoking.

    Science.gov (United States)

    1986-07-01

    The 39th World Health Assembly, which met in May 1986, recognized the escalating health problem of smoking-related diseases and affirmed that tobacco smoking and its use in other forms are incompatible with the attainment of "Health for All by the Year 2000." If properly implemented, antismoking campaigns can decrease the prevalence of smoking. Nations as a whole must work toward changing smoking habits, and governments must support these efforts by officially stating their stand against smoking. Over 60 countries have introduced legislation affecting smoking. The variety of policies range from adopting a health education program designed to increase peoples' awareness of its dangers to increasing taxes to deter smoking by increasing tobacco prices. Each country must adopt an antismoking campaign which works most effectively within the cultural parameters of the society. Other smoking policies include: printed warnings on cigarette packages; health messages via radio, television, mobile teams, pamphlets, health workers, clinic walls, and newspapers; prohibition of smoking in public areas and transportation; prohibition of all advertisement of cigarettes and tobacco; and the establishment of upper limits of tar and nicotine content in cigarettes. The tobacco industry spends about $2000 million annually on worldwide advertising. According to the World Health Organization (WHO), controlling this overabundance of tobacco advertisements is a major priority in preventing the spread of smoking. Cigarette and tobacco advertising can be controlled to varying degrees, e.g., over a dozen countries have enacted a total ban on advertising on television or radio, a mandatory health warning must accompany advertisements in other countries, and tobacco companies often are prohibited from sponsoring sports events. Imposing a substantial tax on cigarettes is one of the most effective means to deter smoking. However, raising taxes and banning advertisements is not enough because

  9. Up-to-Date Materials of Gas Ducts and Smoke Stacks

    Directory of Open Access Journals (Sweden)

    V. D. Sizov

    2012-01-01

    Full Text Available The paper considers existing systems of smoke removal from heat-generating plants of various heat power. Advantages and disadvantages of every system are specified in the paper. The paper analyzes properties of fiberglass smoke stacks.

  10. Gender differences in smoking following an implicit mood induction.

    Science.gov (United States)

    Weinberger, Andrea H; McKee, Sherry A

    2012-05-01

    Smoking is significantly associated with negative affect, which may play an especially important role in the smoking behavior of women. The purpose of this laboratory study was to examine the role of gender in the relationship of negative mood and smoking maintenance for male and female smokers following an implicit mood induction using music. Ninety adult smokers (50% female) completed a laboratory session during which they were randomly assigned to a negative mood induction, a positive mood induction, or a neutral mood condition. Latency to smoke and number of cigarettes smoked were assessed during an ad libitumsmoking period following the mood induction. Female smokers began smoking more quickly following the negative mood induction when compared with males. There were no gender differences in the number of cigarettes smoked or for cravings to smoke by mood condition. This study demonstrated gender differences in the relationship between negative affect and smoking behavior following an implicit and subtle mood manipulation. A better understanding of gender differences in smoking behavior can provide valuable information about mechanisms that maintain smoking behavior and guide treatment development to help adults quit smoking.

  11. Relationships Between Social Anxiety and Smoking-Specific Experiential Avoidance.

    Science.gov (United States)

    Watson, Noreen L; Heffner, Jaimee L; McClure, Jennifer B; Bricker, Jonathan B

    2017-01-01

    Although social anxiety is associated with higher prevalence of smoking and lower cessation rates, little is known about the underlying mechanisms of these relationships. Research suggests that socially anxious smokers have higher levels of smoking-specific experiential avoidance and are inclined to smoke to avoid internal smoking cues. However, it is unknown which types of internal smoking cues they avoid. Thus, this study aimed to address this gap in the literature. Participants (N = 450) were adult smokers from a group-based trial for smoking cessation. Bivariate correlations and hierarchical linear regression models examined relationships between baseline levels of social anxiety and acceptance of internal smoking cues-physical sensations, emotions, and cognitions. Social anxiety was associated with lower levels of acceptance of thoughts, sensations, and emotions that cue smoking. After controlling for levels of nicotine dependence, depression, generalized anxiety, and posttraumatic stress disorder, social anxiety still explained unique variability in overall acceptance of internal smoking cues and in acceptance of physical sensations and emotions that serve as smoking cues. Social anxiety no longer explained unique variability in acceptance of thoughts that trigger smoking. Smokers with high levels of social anxiety are less accepting of internal smoking cues. For physical and emotional cues, this effect was independent of level of dependence and mental health comorbidity. Results help explain why smokers with social anxiety are less likely to quit and can inform the development of targeted cessation treatments for smokers with social anxiety.

  12. [Influence of fish smoking technology on nitrosamine concentration in them].

    Science.gov (United States)

    Gorelova, N D; Dikun, P P; Emshanova, A V; Nazarova, Z A

    1976-01-01

    Under study was the content of total nitrosoamines in chiloed and bloated cod prepared by three ways: 1) by common bloating with fire-wood smoke; 2) by sawdust cold smoke (produced by means of a smoke generator) in thermal treatment with gas combustion products; 3) by the smoking fluid "Vakhtol" also in thermal treatment with gas combustion products. The common bloating resulted in the appearance of large amounts of total nitrosoamines in the foodstuff (from 200 to 900 mKg/Kg). Fish treatment with sawdust smoke would cause an insignificant increase in the content of these agents only in some cases. Whereas an application of the smoking fluid fails to produce any increase in nitrosoamines content. The use of wood-fire smoke for bloating Trachurus did not change its nitrosoamines content at all. The content of nitrosoamines was found to depend also on the duration of cod preservation in a frozen state.

  13. Generation of high-voltage pulses with a subnanosecond leading edge in an open discharge. II. Switching mechanism

    Science.gov (United States)

    Bokhan, P. A.; Gugin, P. P.; Zakrevskii, D. E.; Lavrukhin, M. A.

    2015-10-01

    The mechanism of fast switching in open-discharge-based devices is clarified by analyzing the feature of the I-V characteristic of a quasi-stationary open discharge: at a voltage of 3-4 kV, the characteristic sharply rises, obeying the law j ~ U y with y > 10 ( j is the current density). Such a run of the curve is explained by the fact that at U > 3 kV helium atom excitation by fast helium atoms becomes the main reason for VUV radiation. Fast helium atoms result from the resonance charge exchange between He+ ions moving from the anode to the cathode. In the coaxial design and in the sandwich design consisting of two accelerating gaps in which electrons move toward each other, multiple oscillations of electrons take place. This favors the generation of fast atoms and, accordingly, resonance VUV photons. Switching times as short as 0.5 ns are achieved. The minimal switching time estimated from experimental data equals 100 ps.

  14. Multiscale representation of generating and correlation functions for some models of statistical mechanics and quantum field theory

    International Nuclear Information System (INIS)

    O'Carroll, M.

    1993-01-01

    The author considers models of statistical mechanics and quantum field theory (in the Euclidean formulation) which are treated using renormalization group methods and where the action is a small perturbation of a quadratic action. The author obtains multiscale formulas for the generating and correlation functions after n renormalization group transformations which bring out the relation with the nth effective action. The author derives and compares the formulas for different RGs. The formulas for correlation functions involve (1) two propagators which are determined by a sequence of approximate wave function renormalization constants and renormalization group operators associated with the decomposition into scales of the quadratic form and (2) field derivatives of the nth effective action. For the case of the block field open-quotes δ-functionclose quotes RG the formulas are especially simple and for asymptotic free theories only the derivatives at zero field are needed; the formulas have been previously used directly to obtain bounds on correlation functions using information obtained from the analysis of effective actions. The simplicity can be traced to an open-quotes orthogonality-of-scalesclose quotes property which follows from an implicit wavelet structure. Other commonly used RGs do not have the open-quotes orthogonality of scalesclose quotes property. 19 refs

  15. Lithospheric rheology and Moho upheaval control the generation mechanism of the intraplate earthquakes in the North China Basin

    Science.gov (United States)

    Liu, Chang; Zhu, Bojing; Shi, Yaolin

    2016-05-01

    Many devastating intraplate earthquakes, such as the 1966 Xingtai earthquake (Ms 7.2) and the 1976 Tangshan earthquake (Ms 7.8), occurred in the North China Basin (NCB). This study aims to investigate the generation mechanism of the large intraplate earthquakes in the NCB and the spatial distribution of earthquake activity through numerical experiments. In order to simulate the interseismic stress accumulation process in the NCB, we set up several 3D finite element models based on different lithospheric rheological structure and apply boundary conditions of horizontal compression. We find that stress concentration with high rate in the regions where Moho upheaves is responsible for the large earthquakes in the NCB. During the interseismic period large stress rate is located nearly around the bottom of the brittle upper crust, where stress accumulates fast to reach fault strength and active the main shocks. Aftershocks in the seismogenic layers could be triggered by the main shocks. Two factors are critical to the crustal stress accumulation process. (1) The first is Moho upheaval in the seismic zones. (2) The second is viscosity contrast among the crustal layers. Our results support the lithospheric rheological structure in the NCB as following: the brittle upper crust, brittle-ductile transition in the middle crust, the ductile lower crust, and the ductile lithospheric upper mantle.

  16. The mechanism behind internally generated centennial-to-millennial scale climate variability in an earth system model of intermediate complexity

    Directory of Open Access Journals (Sweden)

    T. Friedrich

    2010-08-01

    Full Text Available The mechanism triggering centennial-to-millennial-scale variability of the Atlantic Meridional Overturning Circulation (AMOC in the earth system model of intermediate complexity LOVECLIM is investigated. It is found that for several climate boundary conditions such as low obliquity values (~22.1° or LGM-albedo, internally generated centennial-to-millennial-scale variability occurs in the North Atlantic region. Stochastic excitations of the density-driven overturning circulation in the Nordic Seas can create regional sea-ice anomalies and a subsequent reorganization of the atmospheric circulation. The resulting remote atmospheric anomalies over the Hudson Bay can release freshwater pulses into the Labrador Sea and significantly increase snow fall in this region leading to a subsequent reduction of convective activity. The millennial-scale AMOC oscillations disappear if LGM bathymetry (with closed Hudson Bay is prescribed or if freshwater pulses are suppressed artificially. Furthermore, our study documents the process of the AMOC recovery as well as the global marine and terrestrial carbon cycle response to centennial-to-millennial-scale AMOC variability.

  17. Smoking reduction, smoking cessation, and mortality

    DEFF Research Database (Denmark)

    Godtfredsen, Nina S; Holst, Claus; Prescott, Eva

    2002-01-01

    The authors investigated the association between changes in smoking habits and mortality by pooling data from three large cohort studies conducted in Copenhagen, Denmark. The study included a total of 19,732 persons who had been examined between 1967 and 1988, with reexaminations at 5- to 10-year...... intervals and a mean follow-up of 15.5 years. Date of death and cause of death were obtained by record linkage with nationwide registers. By means of Cox proportional hazards models, heavy smokers (>or=15 cigarettes/day) who reduced their daily tobacco intake by at least 50% without quitting between...... the first two examinations and participants who quit smoking were compared with persons who continued to smoke heavily. After exclusion of deaths occurring in the first 2 years of follow-up, the authors found the following adjusted hazard ratios for subjects who reduced their smoking: for cardiovascular...

  18. Mechanics

    CERN Document Server

    Hartog, J P Den

    1961-01-01

    First published over 40 years ago, this work has achieved the status of a classic among introductory texts on mechanics. Den Hartog is known for his lively, discursive and often witty presentations of all the fundamental material of both statics and dynamics (and considerable more advanced material) in new, original ways that provide students with insights into mechanical relationships that other books do not always succeed in conveying. On the other hand, the work is so replete with engineering applications and actual design problems that it is as valuable as a reference to the practicing e

  19. Comparison of in vitro toxicological effects of biomass smoke from different sources of animal dung.

    Science.gov (United States)

    McCarthy, Claire E; Duffney, Parker F; Wyatt, Jeffrey D; Thatcher, Thomas H; Phipps, Richard P; Sime, Patricia J

    2017-09-01

    Worldwide, over 4 million premature deaths each year are attributed to the burning of biomass fuels for cooking and heating. Epidemiological studies associate household air pollution with lung diseases, including chronic obstructive pulmonary disease, lung cancer, and respiratory infections. Animal dung, a biomass fuel used by economically vulnerable populations, generates more toxic compounds per mass burned than other biomass fuels. The type of animal dung used varies widely depending on local agro-geography. There are currently neither standardized experimental systems for dung biomass smoke research nor studies assessing the health impacts of different types of dung smoke. Here, we used a novel reproducible exposure system to assess outcomes related to inflammation and respiratory infections in human airway cells exposed to six different types of dung biomass smoke. We report that dung biomass smoke, regardless of species, is pro-inflammatory and activates the aryl hydrocarbon receptor and JNK transcription factors; however, dung smoke also suppresses interferon responses after a challenge with a viral mimetic. These effects are consistent with epidemiological data, and suggest a mechanism by which the combustion of animal dung can directly cause lung diseases, promote increased susceptibility to infection, and contribute to the global health problem of household air pollution. Copyright © 2017. Published by Elsevier Ltd.

  20. Effect of Smoking on Blood Pressure and Resting Heart Rate

    DEFF Research Database (Denmark)

    Linneberg, Allan; Jacobsen, Rikke K; Skaaby, Tea

    2015-01-01

    BACKGROUND: -Smoking is an important cardiovascular disease risk factor, but the mechanisms linking smoking to blood pressure are poorly understood. METHODS AND RESULTS: -Data on 141,317 participants (62,666 never, 40,669 former, 37,982 current smokers) from 23 population-based studies were...... included in observational and Mendelian randomisation (MR) meta-analyses of the associations of smoking status and smoking heaviness with systolic and diastolic blood pressure (SBP, DBP), hypertension, and resting heart rate. For the MR analyses, a genetic variant rs16969968/rs1051730 was used as a proxy...... for smoking heaviness in current smokers. In observational analyses, current as compared with never smoking was associated with lower SBP, DBP, and lower hypertension risk, but with higher resting heart rate. In observational analyses amongst current smokers, one cigarette/day higher level of smoking...

  1. Parental smoking, exposure to secondhand smoke at home, and smoking initiation among young children.

    Science.gov (United States)

    Wang, Man Ping; Ho, Sai Yin; Lam, Tai Hing

    2011-09-01

    To investigate the associations of parental smoking and secondhand smoke (SHS) exposure at home with smoking initiation among young children in Hong Kong. A prospective school-based survey of Hong Kong primary 2-4 students was conducted at baseline in 2006 and followed up in 2008. Self-administered anonymous questionnaires were used to collect information about smoking, SHS exposure at home, parental smoking, and sociodemographic characteristics. Cross-sectional and prospective associations of SHS exposure at home and parental smoking with student smoking were analyzed using logistic regression adjusting for potential confounders. Cross-sectional association between parental smoking and ever smoking was significant with adjustment of sociodemographic characteristics but became insignificant after adjusting for home SHS exposure. Home SHS exposure mediated the association between parental smoking and students smoking (p = .03). Prospectively, parental smoking was not associated with smoking initiation after adjusting for home SHS exposure. Each day increase in home SHS exposure significantly predicted 16% excess risk of smoking initiation after adjusting for parental smoking. The prospective effect of parental smoking on smoking initiation was significantly mediated by baseline home SHS exposure (p effect of parental smoking on smoking initiation was mediated through SHS exposure at home. To prevent children from smoking as well as the harm of SHS exposure, parents and other family members should quit smoking or at least reduce smoking at home.

  2. Effects of smoking cues in movies on immediate smoking behavior

    NARCIS (Netherlands)

    Lochbühler, K.C.; Peters, P.M.; Scholte, R.H.J.; Engels, R.C.M.E.

    2010-01-01

    The objective of this study was to investigate the effect of smoking cues in movies on immediate smoking behavior. We tested whether smokers who are confronted with smoking characters in a movie smoke more cigarettes while watching than those confronted with non-smoking characters and whether this

  3. Effects of smoking cues in movies on immediate smoking behavior

    NARCIS (Netherlands)

    Lochbuehler, K.; Peters, M.; Scholte, R.H.J.; Engels, R.C.M.E.

    2010-01-01

    Introduction: The objective of this study was to investigate the effect of smoking cues in movies on immediate smoking behavior. We tested whether smokers who are confronted with smoking characters in a movie smoke more cigarettes while watching than those confronted with non-smoking characters and

  4. Legislative smoking bans for reducing exposure to secondhand smoke and smoking prevalence: Opportunities for Georgians.

    Science.gov (United States)

    Coughlin, Steven S; Anderson, Jennifer; Smith, Selina A

    2015-01-01

    Secondhand smoke, which is also referred to as environmental tobacco smoke and passive smoke, is a known human carcinogen. Secondhand smoke also causes disease and premature death in nonsmoking adults and children. We summarize studies of secondhand smoke in public places before and after smoking bans, as well as studies of cardiovascular and respiratory disease before and after such bans. To protect the public from the harmful effects of secondhand smoke, smoke-free legislation is an effective public health measure. Smoking bans in public places, which have been implemented in many jurisdictions across the U.S. and in other countries, have the potential to influence social norms and reduce smoking behavior. Through legislative smoking bans for reducing secondhand smoke exposure and smoking prevalence, opportunities exist to protect the health of Georgians and other Americans and to reduce health care costs. These opportunities include increasing the comprehensiveness of smoking bans in public places and ensuring adequate funding to quit line services.

  5. The impact of active and passive peer influence on young adult smoking: an experimental study.

    Science.gov (United States)

    Harakeh, Zeena; Vollebergh, Wilma A M

    2012-03-01

    Peers influence adolescent and young adult smoking, but little is known about the underlying mechanisms. It is necessary to understand whether the current assumption of peer pressure is valid, or whether an alternative explanation as imitation is more appropriate. We examined whether passive (imitation) and/or active (pressure) peer influence affects young adult smoking. An experiment was conducted among 68 daily-smoking students aged 16-24. The actual study aim was masked. Participants had to do a 30-min music task with a confederate. The experiment consisted of a 2 (smoking condition: confederate smokes or not) by 2 (pressure condition: confederate offers the participant a cigarette or not) factorial design, resulting in four conditions: (1) no smoking and no pressure (N=15); (2) smoking but no pressure (N=16); (3) pressure but no smoking (N=20); and (4) smoking and pressure (N=17). The primary outcome tested was the total number of cigarettes smoked during this music assignment. Peer smoking significantly predicted the total number of cigarettes smoked by young adults while peer pressure did not. The interaction effect of peer pressure and peer smoking was not significant. Peer pressure did not have a significant additional contribution, over and above smoking of the peer. Passive (imitation) peer influence affected young adult smoking rather than active (pressure) peer influence. Thus, smoking cessation efforts should aim at preventing interaction with smoking peers and raising awareness about its impact. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  6. Using Second Harmonic Generation Microscopy to Study the Three-Dimensional Structure of Collagen and its Degradation Mechanism

    Science.gov (United States)

    Mega, Yair

    Collagen is one of the most abundant proteins found in the human body. Its crystalline structure possesses no centrosymmetry, allowing it to emit second-harmonic waves. Second harmonic generation (SHG) microscopy utilizes the latter quality to produce high-resolution images of collagen rich tissues and therefore become a key research tool in the biomedical field. We developed a new model, intended to be used together with second harmonic generation (SHG) microscopy, to thoroughly investigate collagen-based tissues. We use our SHG model to reveal information in real time from enzymatic biochemical processes. We also present a novel method used to measure quantitatively the direction of the fibers within the tissue, from SHG images. Using this method, we were able to reconstruct an angular map of the orientation of collagen fibers from multiple sections across the entire area of a human cornea. The structure we obtained demonstrates the criss-crossing structure of the human cornea, previously suggested in the literature. In addition, we also report work on a unique step-wise three-photon fluorescence excitation discovered in melanin. This unique fluorescence mechanism was exploited to discriminate melanin on a small-size, low-cost and low laser power setup which was used as a prototype for a handheld device. The latter study is a part of a larger on-going effort in our group to explore new diagnosis methods to be used for early skin cancer screening. Finally, this work demonstrates a spectroscopy-based method to correct for blood vessel thickness effect. The method analyzes spectral shift from a molecular imaging agent and correlate the shifts to the length of the optical path in blood. The correction method described in this work is intended to be implemented on a guided catheter near infrared fluorescence (NIRF) intra-vascular imaging system. In this imaging system, this study's results will used to correct for the radial distance between the imaging tip of the

  7. Determination of Pesticide Residues in Cannabis Smoke

    Directory of Open Access Journals (Sweden)

    Nicholas Sullivan

    2013-01-01

    Full Text Available The present study was conducted in order to quantify to what extent cannabis consumers may be exposed to pesticide and other chemical residues through inhaled mainstream cannabis smoke. Three different smoking devices were evaluated in order to provide a generalized data set representative of pesticide exposures possible for medical cannabis users. Three different pesticides, bifenthrin, diazinon, and permethrin, along with the plant growth regulator paclobutrazol, which are readily available to cultivators in commercial products, were investigated in the experiment. Smoke generated from the smoking devices was condensed in tandem chilled gas traps and analyzed with gas chromatography-mass spectrometry (GC-MS. Recoveries of residues were as high as 69.5% depending on the device used and the component investigated, suggesting that the potential of pesticide and chemical residue exposures to cannabis users is substantial and may pose a significant toxicological threat in the absence of adequate regulatory frameworks.

  8. Mechanism of generation of large (Ti,Nb,V)(C,N)-type precipitates in H13 + Nb tool steel

    Science.gov (United States)

    Xie, You; Cheng, Guo-guang; Chen, Lie; Zhang, Yan-dong; Yan, Qing-zhong

    2016-11-01

    The characteristics and generation mechanism of (Ti,Nb,V)(C,N) precipitates larger than 2 μm in Nb-containing H13 bar steel were studied. The results show that two types of (Ti,Nb,V)(C,N) phases exist—a Ti-V-rich one and an Nb-rich one—in the form of single or complex precipitates. The sizes of the single Ti-V-rich (Ti,Nb,V)(C,N) precipitates are mostly within 5 to 10 μm, whereas the sizes of the single Nb-rich precipitates are mostly 2-5 μm. The complex precipitates are larger and contain an inner Ti-V-rich layer and an outer Nb-rich layer. The compositional distribution of (Ti,Nb,V)(C,N) is concentrated. The average composition of the single Ti-V-rich phase is (Ti0.511V0.356Nb0.133)(C x N y ), whereas that for the single Nb-rich phase is (Ti0.061V0.263Nb0.676)(C x N y ). The calculation results based on the Scheil-Gulliver model in the Thermo-Calc software combining with the thermal stability experiments show that the large phases precipitate during the solidification process. With the development of solidification, the Ti-V-rich phase precipitates first and becomes homogeneous during the subsequent temperature reduction and heat treatment processes. The Nb-rich phase appears later.

  9. Health literacy and smoking

    Directory of Open Access Journals (Sweden)

    Rahman Panahi

    2018-01-01

    Full Text Available Although both population-based and clinical interventions have been successful in lowering rates of smoking in the USA over time, the prevalence of smoking remains considerably higher than the Healthy People 2020 objective of 12% [1]. The latest national study conducted in Iran showed that 25% of the population aged 18- 65 years were smokers and age, education, gender, occupation, and marital status variables had a significant relationship with smoking [2].

  10. Cigarette Smoking in Iran

    OpenAIRE

    Meysamie, A; Ghaletaki, R; Zhand, N; Abbasi, M

    2012-01-01

    Background: Cigarette smoking is the largest preventable cause of death worldwide. No systematic review is available on the situation of the smoking in Iran, so we decided to provide an overview of the studies in the field of smoking in Iranian populations. Methods: Published Persian-language papers of all types until 2009 indexed in the IranMedex (http://www.iranmedex.com) and Magiran (http://www.magiran.com). Reports of World Health Organization were also searched and optionally employed. T...

  11. Mechanisms and timescales of generating eruptible rhyolitic magmas at Yellowstone caldera from zircon and sanidine geochronology and geochemistry

    Science.gov (United States)

    Stelten, Mark; Cooper, Kari M.; Vazquez, Jorge A.; Calvert, Andrew T.; Glessner, Justin G

    2015-01-01

    We constrain the physical nature of the magma reservoir and the mechanisms of rhyolite generation at Yellowstone caldera via detailed characterization of zircon and sanidine crystals hosted in three rhyolites erupted during the (ca. 170 – 70 ka) Central Plateau Member eruptive episode – the most recent post-caldera magmatism at Yellowstone. We present 238U-230Th crystallization ages and trace-element compositions of the interiors and surfaces (i.e., unpolished rims) of individual zircon crystals from each rhyolite. We compare these zircon data to 238U- 230Th crystallization ages of bulk sanidine separates coupled with chemical and isotopic data from single sanidine crystals. Zircon age and trace-element data demonstrate that the magma reservoir that sourced the Central Plateau Member rhyolites was long-lived (150 – 250 kyr) and genetically related to the preceding episode of magmatism, which occurred ca. 256 ka. The interiors of most zircons in each rhyolite were inherited from unerupted material related to older stages of Central Plateau Member magmatism or the preceding late Upper Basin Member magmatism (i.e., are antecrysts). Conversely, most zircon surfaces crystallized near the time of eruption from their host liquids (i.e., are autocrystic). The repeated recycling of zircon interiors from older stages of magmatism demonstrates that sequentially erupted Central Plateau Member rhyolites are genetically related. Sanidine separates from each rhyolite yield 238U-230Th crystallization ages at or near the eruption age of their host magmas, coeval with the coexisting zircon surfaces, but are younger than the coexisting zircon interiors. Chemical and isotopic data from single sanidine crystals demonstrate that the sanidines in each rhyolite are in equilibrium with their host melts, which considered along with their near-eruption crystallization ages suggests that nearly all CPM sanidines are autocrystic. The paucity of antecrystic sanidine crystals relative to

  12. Smoke production in fires

    Energy Technology Data Exchange (ETDEWEB)

    Sarvaranta, L.; Kokkala, M. [VTT Building Technology, Espoo (Finland). Building Physics, Building Services and Fire Technology

    1995-12-31

    Characterization of smoke, factors influencing smoke production and experimental methods for measuring smoke production are discussed in this literature review. Recent test-based correlation models are also discussed. Despite the large number of laboratories using different fire testing methods, published smoke data have been scarce. Most technical literature on smoke production from building materials is about experimental results in small scale tests. Compilations from cone calorimeter tests have been published for a few materials, e.g. upholstered furniture materials and some building products. Mass optical density data and compilations of gravimetric soot data are available for various materials as well as a number of smoke obscuration values. For a given material often a wide range of values of smoke output can be found in the literature and care should be exercised in applying the appropriate value in each case. In laboratory experiments, the production of smoke and its optical properties are often measured simultaneously with other fire properties as heat release and flame spread. The measurements are usually dynamic in full scale, i.e. they are performed in a flow-through system. In small scale they may be either dynamic, as in the cone calorimeter, or static, i.e. the smoke is accumulated in a closed box. Small-scale tests are necessary as practical tools. Full-scale tests are generally considered to be more reliable and are needed to validitate the small-scale tests

  13. [Tobacco smoke exposure levels and lipide profile].

    Science.gov (United States)

    Zielińska-Danch, Wioleta; Czogała, Jan; Sobczak, Andrzej; Grela, Wioleta; Gnyp, Wojciech

    2008-01-01

    Toxic tobacco smoke exposure to human organism is strictly related to progress of atherosclerosis changes. One of the mechanisms of these effects is a change of blood lipoprotein fraction concentrations. The concentrations of the lipid profile parameters (TCL, HDL, LDL, TG) and the chosen biomarkers (urine cotinine and 1-hydroxypyrene and blood carboxyhaemoglobine) were determined. It was studied whether the procedure of the groups determination (nonsmokers, passive and active smokers) affect the calculated average values of lipid profile parameters. The role of the applied biomarkers for the detection of the effects related to the tobacco smoke exposure is also discussed. It is concluded that there is no difference among the lipid profiles of passive smokers and nonsmokers. Cigarette smoking increases and lowers the TG and HDL concentrations, respectively. Urine cotinine seems to be the best indicator of tobacco smoke exposure among three chosen biomarkers. Study subjects were 300 male and female volunteers.

  14. Smoking reduction, smoking cessation, and mortality

    DEFF Research Database (Denmark)

    Godtfredsen, Nina S; Holst, Claus; Prescott, Eva

    2002-01-01

    The authors investigated the association between changes in smoking habits and mortality by pooling data from three large cohort studies conducted in Copenhagen, Denmark. The study included a total of 19,732 persons who had been examined between 1967 and 1988, with reexaminations at 5- to 10-year...... the first two examinations and participants who quit smoking were compared with persons who continued to smoke heavily. After exclusion of deaths occurring in the first 2 years of follow-up, the authors found the following adjusted hazard ratios for subjects who reduced their smoking: for cardiovascular...... diseases, hazard ratio (HR) = 1.01 (95% confidence interval (CI): 0.76, 1.35); for respiratory diseases, HR = 1.20 (95% CI: 0.70, 2.07); for tobacco-related cancers, HR = 0.91 (95% CI: 0.63, 1.31); and for all-cause mortality, HR = 1.02 (95% CI: 0.89, 1.17). In subjects who stopped smoking, most estimates...

  15. Cigarette smoking and brain regulation of energy homeostasis

    OpenAIRE

    Hui eChen; Hui eChen; Sonia eSaad; Shaun eSandow; Paul eBertrand

    2012-01-01

    Cigarette smoking is an addictive behaviour, and is the primary cause of cardiovascular and pulmonary disease, and cancer (among other diseases). Cigarette smoke contains thousands of components that may affect caloric intake and energy expenditure, although nicotine is the major addictive substance present, and has the best described actions. Nicotine exposure from cigarette smoke can change brain feeding regulation to reduce appetite via both energy homeostatic and reward mechanisms, causin...

  16. Cigarette Smoking and Brain Regulation of Energy Homeostasis

    OpenAIRE

    Chen, Hui; Saad, Sonia; Sandow, Shaun L.; Bertrand, Paul P.

    2012-01-01

    Cigarette smoking is an addictive behavior, and is the primary cause of cardiovascular and pulmonary disease, and cancer (among other diseases). Cigarette smoke contains thousands of components that may affect caloric intake and energy expenditure, although nicotine is the major addictive substance present, and has the best described actions. Nicotine exposure from cigarette smoke can change brain feeding regulation to reduce appetite via both energy homeostatic and reward mechanisms, causing...

  17. [Occasional smoking in Norway].

    Science.gov (United States)

    Kvaavik, Elisabeth; Scheffels, Janne; Lund, Marianne

    2014-01-28

    In recent decades, daily smoking has become less common, while occasional smoking has stayed at the same level. The purpose of the study is to describe occasional smokers on the basis of their smoking behaviour and socio-demographic characteristics. Data from Statistics Norway's quarterly surveys of tobacco use in 2010 and 2011 were used. Information on smoking habits, smoking-related behaviour and the respondents' attitudes to their own smoking was collected in telephone interviews. Of the 8,700 men and women aged 16-74 (response rate 57%) who were included, altogether 1,583 were daily smokers and 907 occasional smokers. The occasional smokers were younger, more frequently lived in large cities and had a higher level of education and income than the daily smokers. Twenty-nine of 174 (17%) occasional smokers used snus on a daily basis, compared to 10 of 394 (3%) of the daily smokers. The occasional smokers had great confidence in their ability to quit: 95% responded that they would be smoke-free in five years, compared to 55% of the daily smokers (n = 2,158). Fifty-five (35%) of the occasional smokers lit up several times weekly (16 cigarettes per week on average), while the remaining (65%) smoked only once per week as a maximum (five cigarettes per week on average). Those who smoked several times each week had attitudes to their own smoking and usage pattern for tobacco that were similar to those of the daily smokers. Nearly half of the occasional smokers defined themselves as non-smokers. Norwegian occasional smokers are a heterogeneous group in terms of their smoking pattern and frequency, and many define themselves as non-smokers.

  18. Recent trends in smoking prevalence in South Africa - Some ...

    African Journals Online (AJOL)

    Objective. To estimate trends in smoking prevalence among different demographic and income segments for the period 1993- 2000. Methodology. Annual data were obtained from a commercially generated database focusing on product usage. Using regression techniques, trends in smoking prevalence were estimated.

  19. Exposure of aconitase to smoking-related oxidants results in iron loss and increased iron response protein-1 activity: potential mechanisms for iron accumulation in human arterial cells

    DEFF Research Database (Denmark)

    Talib, Jihan; Davies, Michael Jonathan

    2016-01-01

    of the cytosolic isoform to iron response protein-1, which regulates intracellular iron levels. We show that exposure of isolated aconitase to increasing concentrations of HOSCN releases iron from the aconitase [Fe-S]4 cluster, and decreases enzyme activity. This is associated with protein thiol loss...... and modification of specific Cys residues in, and around, the [Fe-S]4 cluster. Exposure of HCAEC to HOSCN resulted in increased intracellular levels of chelatable iron, loss of aconitase activity and increased iron response protein-1 (IRP-1) activity. These data indicate HOSCN, an oxidant associated with oxidative...... stress in smokers, can induce aconitase dysfunction in human endothelial cells via Cys oxidation, damage to the [Fe-S]4 cluster, iron release and generation of IRP-1 activity, which modulates ferritin protein levels and results in dysregulation of iron metabolism. These data may rationalise, in part...

  20. Research of the elastic waves generated by a pulse laser. Excitation mechanism of elastic waves and application to nondestructive testing; Pulse laser de reikishita danseiha ni kansuru kenkyu. Danseiha reiki no mechanism to hihakai kensa eno oyo

    Energy Technology Data Exchange (ETDEWEB)

    Cho, H.; Takemoto, M. [Aoyama Gakuin University, Tokyo (Japan). College of Science and Engineering

    1994-07-20

    A bulk wave is generated when a pulse laser is irradiated to the material, and the characteristics of a Young`s modulus and Poisson`s ratio can be nondestructively estimated from the bulk wave. The generation mechanism of laser ultrasonic waves must be first clarified for such application. In this paper, fundamental research was conducted to study the generation mechanism of the elastic waves excited by a Q-switched Nd-YAG laser, and the generation method and characteristics of Rayleigh waves. The following result was obtained. A bulk wave is generated by the disk-like adiabatic expansion near the surface if the laser power is small when a spot-shape pulse laser was irradiated. A bulk wave is generated by the thin disk-like adiabatic expansion beneath the surface due to the thermal diffusion in the depth direction of a base material when the laser power becomes large. Moreover, a bulk wave is generated by the impact force due to abrasion and plasma when the power becomes still larger. The information on the bulk wave characteristics and Rayleigh wave was also obtained. 25 refs., 15 figs., 1 tab.

  1. Through the smoke: Use of in vivo and in vitro cigarette smoking models to elucidate its effect on female fertility

    Energy Technology Data Exchange (ETDEWEB)

    Camlin, Nicole J. [School of Environment and Life Sciences, University of Newcastle, Callaghan, NSW 2308 (Australia); McLaughlin, Eileen A., E-mail: eileen.mclaughlin@newcastle.edu.au [School of Environment and Life Sciences, University of Newcastle, Callaghan, NSW 2308 (Australia); Holt, Janet E. [School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308 (Australia)

    2014-12-15

    A finite number of oocytes are established within the mammalian ovary prior to birth to form a precious ovarian reserve. Damage to this limited pool of gametes by environmental factors such as cigarette smoke and its constituents therefore represents a significant risk to a woman's reproductive capacity. Although evidence from human studies to date implicates a detrimental effect of cigarette smoking on female fertility, these retrospective studies are limited and present conflicting results. In an effort to more clearly understand the effect of cigarette smoke, and its chemical constituents, on female fertility, a variety of in vivo and in vitro animal models have been developed. This article represents a systematic review of the literature regarding four of experimental model types: 1) direct exposure of ovarian cells and follicles to smoking constituents’ in vitro, 2) direct exposure of whole ovarian tissue with smoking constituents in vitro, 3) whole body exposure of animals to smoking constituents and 4) whole body exposure of animals to cigarette smoke. We summarise key findings and highlight the strengths and weaknesses of each model system, and link these to the molecular mechanisms identified in smoke-induced fertility changes. - Highlights: • In vivo exposure to individual cigarette smoke chemicals alters female fertility. • The use of in vitro models in determining molecular mechanisms • Whole cigarette smoke inhalation animal models negatively affect ovarian function.

  2. Through the smoke: Use of in vivo and in vitro cigarette smoking models to elucidate its effect on female fertility

    International Nuclear Information System (INIS)

    Camlin, Nicole J.; McLaughlin, Eileen A.; Holt, Janet E.

    2014-01-01

    A finite number of oocytes are established within the mammalian ovary prior to birth to form a precious ovarian reserve. Damage to this limited pool of gametes by environmental factors such as cigarette smoke and its constituents therefore represents a significant risk to a woman's reproductive capacity. Although evidence from human studies to date implicates a detrimental effect of cigarette smoking on female fertility, these retrospective studies are limited and present conflicting results. In an effort to more clearly understand the effect of cigarette smoke, and its chemical constituents, on female fertility, a variety of in vivo and in vitro animal models have been developed. This article represents a systematic review of the literature regarding four of experimental model types: 1) direct exposure of ovarian cells and follicles to smoking constituents’ in vitro, 2) direct exposure of whole ovarian tissue with smoking constituents in vitro, 3) whole body exposure of animals to smoking constituents and 4) whole body exposure of animals to cigarette smoke. We summarise key findings and highlight the strengths and weaknesses of each model system, and link these to the molecular mechanisms identified in smoke-induced fertility changes. - Highlights: • In vivo exposure to individual cigarette smoke chemicals alters female fertility. • The use of in vitro models in determining molecular mechanisms • Whole cigarette smoke inhalation animal models negatively affect ovarian function

  3. In vitro degradation and mechanical properties of PLA-PCL copolymer unit cell scaffolds generated by two-photon polymerization

    International Nuclear Information System (INIS)

    Felfel, R M; Gimeno-Fabra, Miquel; Ahmed, Ifty; Scotchford, Colin; Grant, David M; Poocza, Leander; Milde, Tobias; Hildebrand, Gerhard; Liefeith, Klaus; Sottile, Virginie

    2016-01-01

    The manufacture of 3D scaffolds with specific controlled porous architecture, defined microstructure and an adjustable degradation profile was achieved using two-photon polymerization (TPP) with a size of 2  ×  4  ×  2 mm 3 . Scaffolds made from poly(D,L-lactide-co-ε-caprolactone) copolymer with varying lactic acid (LA) and ε -caprolactone (CL) ratios (LC16:4, 18:2 and 9:1) were generated via ring-opening-polymerization and photoactivation. The reactivity was quantified using photo-DSC, yielding a double bond conversion ranging from 70% to 90%. The pore sizes for all LC scaffolds were see 300 μm and throat sizes varied from 152 to 177 μm. In vitro degradation was conducted at different temperatures; 37, 50 and 65 °C. Change in compressive properties immersed at 37 °C over time was also measured. Variations in thermal, degradation and mechanical properties of the LC scaffolds were related to the LA/CL ratio. Scaffold LC16:4 showed significantly lower glass transition temperature (T g ) (4.8 °C) in comparison with the LC 18:2 and 9:1 (see 32 °C). Rates of mass loss for the LC16:4 scaffolds at all temperatures were significantly lower than that for LC18:2 and 9:1. The degradation activation energies for scaffold materials ranged from 82.7 to 94.9 kJ mol −1 . A prediction for degradation time was applied through a correlation between long-term degradation studies at 37 °C and short-term studies at elevated temperatures (50 and 65 °C) using the half-life of mass loss (Time (M 1/2 )) parameter. However, the initial compressive moduli for LC18:2 and 9:1 scaffolds were 7 to 14 times higher than LC16:4 (see 0.27) which was suggested to be due to its higher CL content (20%). All scaffolds showed a gradual loss in their compressive strength and modulus over time as a result of progressive mass loss over time. The manufacturing process utilized and the scaffolds produced have potential for use in tissue engineering and regenerative medicine

  4. Smoke Signals: Adolescent Smoking and School Continuation

    OpenAIRE

    Philip J. Cook; Rebecca Hutchinson

    2006-01-01

    This paper presents an exploratory analysis using NLSY97 data of the relationship between the likelihood of school continuation and the choices of whether to smoke or drink. We demonstrate that in the United States as of the late 1990s, smoking in 11th grade was a uniquely powerful predictor of whether the student finished high school, and if so whether the student matriculated in a four-year college. For economists the likely explanation for this empirical link would be based on interpersona...

  5. Smoked Tobacco Products

    Science.gov (United States)

    ... cigarettes in this U.S. Food and Drug Administration (FDA) guidance document How tobacco smoke causes disease in this Centers for Disease ... affects cigarette smoke from this Surgeon General report FDA's work to ensure tobacco products are labeled properly The definitions of common ...

  6. Wildfire Smoke Health Watch

    Centers for Disease Control (CDC) Podcasts

    2012-07-23

    Smoke from wildfires can be dangerous to your health. In this podcast, you will learn the health threats of wildfire smoke and steps you can take to minimize these effects.  Created: 7/23/2012 by Office of Public Health Preparedness and Response (PHPR).   Date Released: 7/23/2012.

  7. Cigar Smoking and Cancer

    Science.gov (United States)

    ... JT, et al. Health risks associated with cigar smoking. Journal of the American Medical Association 2000; 284(6): ... of the U.S. Department of Agriculture System. American Journal of Preventive Medicine ... Institute (1998). Smoking and Tobacco Control Monograph 9: Cigars: Health Effects ...

  8. Smoking and Eye Health

    Science.gov (United States)

    ... Patient Stories Español Eye Health / Tips & Prevention Sections Smoking and Eye Disease Leer en Español: El cigarrillo ... By: Brenda Pagan-Duran MD Apr. 27, 2017 Smoking contributes to a number of major health problems, ...

  9. Smoke without fire

    CERN Multimedia

    Anaïs Schaeffer

    2014-01-01

    Members of the CERN Management recently visited the LHC mock-up at the Safety Training Centre on the Prévessin site. They experienced a realistic emergency simulation, complete with smoke generators and safety alarms.   Simulated helium leak in the LHC mock-up, at the Safety Training Centre on the Prévessin site. Since 2013, the Prévessin Safety Training Centre has been equipped with an LHC tunnel mock-up around 40 m long, where the working and safety conditions faced in the tunnel can be replicated. Throughout the year, this life-size mock-up plays host to numerous CERN and external contractors’ personnel for certain safety training courses, including in particular the ‘Self-Rescue Mask’ and ‘Radiation Protection – Controlled Area’ courses. The CERN firefighters also use it as part of their continuous on-the-job training. The safety course held on 26 May welcomed VIP participants: Rolf Heuer (Direc...

  10. Psoriasis and smoking: links and risks

    Directory of Open Access Journals (Sweden)

    Naldi L

    2016-05-01

    Full Text Available Luigi Naldi1,2 1Department of Dermatology, Azienda Ospedaliera Papa Giovanni XXIII, Bergamo, Italy; 2Study Centre of the Italian Group for Epidemiologic Research in Dermatology (GISED, Bergamo, Italy Abstract: Smoking is a complex environmental exposure influenced by genetic, environmental, and social factors. Nicotine is the principal alkaloid in tobacco that mediates the addicting effects of tobacco products. Tobacco is a mixture of more than 7,000 chemicals, and smoking is recognized as a risk factor for many diseases in humans, including cardiovascular and pulmonary disease and several cancers, and is the single most preventable cause of mortality worldwide. A number of inflammatory immune-related conditions have been associated with smoking, including psoriasis. Smoking affects the onset of psoriasis. In a pooled analysis of 25 case–control studies, the odds ratio of psoriasis among smokers was 1.78 (95% confidence interval [CI]: 1.53–2.06. A dose–effect relationship is also documented. In a pooled analysis of three cohort studies, the risk of incident psoriasis was 1.81 (95% CI: 1.38–2.36 in those who smoked 1–14 cigarettes per day, and 2.29 (95% CI: 1.74–3.01 in those who smoked ≥25 cigarettes per day. Smoking also impacts on the clinical severity of psoriasis, its response to treatment, and explains some of the associated comorbidities, eg, cardiovascular disease, inflammatory bowel disease, and several cancers (especially those of the respiratory tract. Data on the role of smoking in psoriatic arthritis are less consistent compared with those concerning psoriasis. Several pathophysiological mechanisms may explain the association of psoriasis with smoking, including oxidative stress, interaction with signaling pathways active in psoriasis, and vascular influences. In conclusion, psoriasis is just one of the many diseases associated with smoking, but it is visible and disabling. Dermatologists could play a major role in

  11. Smoking and skin disease

    DEFF Research Database (Denmark)

    Thomsen, S F; Sørensen, L T

    2010-01-01

    suggest that tobacco smoking is a contributing factor in systemic lupus erythematosus, psoriasis, palmoplantar pustulosis, cutaneous squamous cell carcinoma, hidradenitis suppurativa, and genital warts. In contrast, smoking may confer some protective effects and mitigate other skin diseases, notably......Tobacco smoking is a serious and preventable health hazard that can cause or exacerbate a number of diseases and shorten life expectancy, but the role of smoking as an etiologic factor in the development of skin disease is largely unknown. Although epidemiological evidence is sparse, findings...... pemphigus vulgaris, pyoderma gangrenosum, aphthous ulcers, and Behçet's disease. Various degenerative dermatologic conditions are also impacted by smoking, such as skin wrinkling and dysregulated wound healing, which can result in post-surgical complications and delayed or even arrested healing of chronic...

  12. Smoking and skin disease

    DEFF Research Database (Denmark)

    Thomsen, S F; Sørensen, L T

    2010-01-01

    Tobacco smoking is a serious and preventable health hazard that can cause or exacerbate a number of diseases and shorten life expectancy, but the role of smoking as an etiologic factor in the development of skin disease is largely unknown. Although epidemiological evidence is sparse, findings...... suggest that tobacco smoking is a contributing factor in systemic lupus erythematosus, psoriasis, palmoplantar pustulosis, cutaneous squamous cell carcinoma, hidradenitis suppurativa, and genital warts. In contrast, smoking may confer some protective effects and mitigate other skin diseases, notably...... pemphigus vulgaris, pyoderma gangrenosum, aphthous ulcers, and Behçet's disease. Various degenerative dermatologic conditions are also impacted by smoking, such as skin wrinkling and dysregulated wound healing, which can result in post-surgical complications and delayed or even arrested healing of chronic...

  13. Circuit bridging of components by smoke

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T.J.; Nowlen, S.P.; Anderson, D.J. [Sandia National Labs., Albuquerque, NM (United States)

    1996-10-01

    Smoke can adversely affect digital electronics; in the short term, it can lead to circuit bridging and in the long term to corrosion of metal parts. This report is a summary of the work to date and component-level tests by Sandia National Laboratories for the Nuclear Regulatory Commission to determine the impact of smoke on digital instrumentation and control equipment. The component tests focused on short-term effects such as circuit bridging in typical components and the factors that can influence how much the smoke will affect them. These factors include the component technology and packaging, physical board protection, and environmental conditions such as the amount of smoke, temperature of burn, and humidity level. The likelihood of circuit bridging was tested by measuring leakage currents and converting those currents to resistance in ohms. Hermetically sealed ceramic packages were more resistant to smoke than plastic packages. Coating the boards with an acrylic spray provided some protection against circuit bridging. The smoke generation factors that affect the resistance the most are humidity, fuel level, and burn temperature. The use of CO{sub 2} as a fire suppressant, the presence of galvanic metal, and the presence of PVC did not significantly affect the outcome of these results.

  14. Circuit bridging of components by smoke

    International Nuclear Information System (INIS)

    Tanaka, T.J.; Nowlen, S.P.; Anderson, D.J.

    1996-10-01

    Smoke can adversely affect digital electronics; in the short term, it can lead to circuit bridging and in the long term to corrosion of metal parts. This report is a summary of the work to date and component-level tests by Sandia National Laboratories for the Nuclear Regulatory Commission to determine the impact of smoke on digital instrumentation and control equipment. The component tests focused on short-term effects such as circuit bridging in typical components and the factors that can influence how much the smoke will affect them. These factors include the component technology and packaging, physical board protection, and environmental conditions such as the amount of smoke, temperature of burn, and humidity level. The likelihood of circuit bridging was tested by measuring leakage currents and converting those currents to resistance in ohms. Hermetically sealed ceramic packages were more resistant to smoke than plastic packages. Coating the boards with an acrylic spray provided some protection against circuit bridging. The smoke generation factors that affect the resistance the most are humidity, fuel level, and burn temperature. The use of CO 2 as a fire suppressant, the presence of galvanic metal, and the presence of PVC did not significantly affect the outcome of these results

  15. Mechanics

    CERN Document Server

    Chester, W

    1979-01-01

    When I began to write this book, I originally had in mind the needs of university students in their first year. May aim was to keep the mathematics simple. No advanced techniques are used and there are no complicated applications. The emphasis is on an understanding of the basic ideas and problems which require expertise but do not contribute to this understanding are not discussed. How­ ever, the presentation is more sophisticated than might be considered appropri­ ate for someone with no previous knowledge of the subject so that, although it is developed from the beginning, some previous acquaintance with the elements of the subject would be an advantage. In addition, some familiarity with element­ ary calculus is assumed but not with the elementary theory of differential equations, although knowledge of the latter would again be an advantage. It is my opinion that mechanics is best introduced through the motion of a particle, with rigid body problems left until the subject is more fully developed. Howev...

  16. International Organization of Standardization (ISO) and Cambridge Filter Test (CFT) Smoking Regimen Data Comparisons in Tobacco Product Marketing Applications.

    Science.gov (United States)

    Chae, Changyu; Walters, Matthew J; Holman, Matthew R

    2017-07-01

    We investigated the differences in TNCO (tar, nicotine, and carbon monoxide) smoke yields generated under the International Organization of Standardization (ISO) and Federal Trade Commission (FTC) Cambridge Filter Test (CFT) smoking regimens. Twenty-nine commercial cigarette products from the US marketplace were acquired in 2015 and tested by measuring the TNCO smoke yields generated under these 2 nonintense smoking regimens. Data obtained demonstrated a linear relationship between the TNCO yields produced under the 2 smoking regimens (R 2 > 0.99). TNCO yields produced by each product were higher under the CFT smoking regimen than the ISO smoking regimen. We found that tar, nicotine, and carbon monoxide yields were consistently 10% to 13% higher under the CFT smoking regimen than under the ISO smoking regimen. This strong correlation indicates that the 2 smoking regimens can be used to apply a correlation correction to CFT TNCO data and allow its comparison to ISO TNCO data in tobacco product marketing applications.

  17. Assessing the role of impulsivity in smoking & non-smoking disordered gamblers.

    Science.gov (United States)

    Boothby, Célina A; Kim, Hyoun S; Romanow, Nicole K; Hodgins, David C; McGrath, Daniel S

    2017-07-01

    Co-morbidity with other addictive behaviors is common in disordered gambling (DG). In particular, tobacco dependence has been found to be among the most prevalent disorders co-morbid with DG. While the extant literature has firmly established the co-occurrence of DG and smoking, there is a paucity of research examining factors that differentiate DGs who smoke from those who do not. To address this empirical gap, the current study tested whether dimensions of trait impulsivity as measured by the UPPS-P Impulsive Behavior Scale (positive urgency, negative urgency, lack of premeditation, lack of perseverance, and sensation seeking), discriminated between non-DGs and DGs based on their present smoking status: non-smoker, occasional smoker, and daily smoker. To this end, 564 community gamblers were recruited through a crowdsourcing platform (Amazon's Mechanical Turk) and completed an online survey, assessing problem gambling severity, tobacco use, and trait impulsivity. MANOVA analyses revealed significant main effects for both gambling severity and smoking status groups. Importantly, a significant gambling by smoking interaction was also found. Pairwise comparisons revealed that DGs who were daily smokers scored higher on negative urgency than those who smoked occasionally or not all. Furthermore, among non-DGs, smoking status failed to discriminate between mean scores on negative urgency. No other significant interaction effects were found for the remaining UPPS-P impulsivity facets. Results suggest that individual components of trait impulsivity, and more specifically negative urgency, successfully differentiate DGs who do not smoke, or just smoke occasionally, from DGs who smoke daily. These findings suggest that the degree of trait impulsivity may potentially distinguish between DGs and DGs who are dually addicted to other substances such as tobacco. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. "Immortal but frightened"-smoking adolescents' perceptions on smoking uptake and prevention

    Directory of Open Access Journals (Sweden)

    Emmelin Maria

    2010-12-01

    Full Text Available Abstract Background To curb the tobacco epidemic a combination of comprehensive interventions are needed at different levels. Smoking uptake is a multi-factorial process that includes societal factors as well as social and individual characteristics. An understanding of the process is essential in order to model interventions. The aim of this study was to explore the role of smoking for young smokers by focusing on the mechanisms that facilitate young people starting to smoke as well as what could have prevented them from starting. Methods A qualitative research design using focus group discussions was chosen as the basis for a content analysis approach. Eight focus groups were conducted with five to six participants in each (four groups with boys, four with girls. The informants were purposively selected to represent smokers in the age range of 15-16 years within the county. The total number of group participants was 44; 21 were girls and 23 boys. The study was performed at 7-9th grade schools in Västerbotten County in northern Sweden. Results Three themes related to different aspects of youth smoking behaviour emerged from the analysis. Theme 1 "gaining control" reflects what makes young people become smokers; theme 2 "becoming a part of the self" focuses on what facilitates youths to start smoking; theme 3 "concerned adults make a difference" indicates what may prevent them from starting. Conclusion Young smokers described starting to smoke as a means of gaining control of feelings and situations during early adolescence. Smoking adolescents expect adults to intervene against smoking. Close relations with concerned adults could be a reason for less frequent smoking or trying to quit smoking. Interventions aimed at normative changes, with consistent messages from both schools and parents about the negative aspects of tobacco seem to be a feasible approach for preventing youth from using tobacco.

  19. Black Cigarette Smokers Report More Attention to Smoking Cues Than White Smokers: Implications for Smoking Cessation.

    Science.gov (United States)

    Robinson, Cendrine D; Pickworth, Wallace B; Heishman, Stephen J; Wetter, David W; Cinciripini, Paul M; Li, Yisheng; Rowell, Brigid; Waters, Andrew J

    2015-08-01

    Black cigarette smokers have lower rates of smoking cessation compared with Whites. However, the mechanisms underlying these differences are not clear. Many Blacks live in communities saturated by tobacco advertisements. These cue-rich environments may undermine cessation attempts by provoking smoking. Moreover, attentional bias to smoking cues (attention capture by smoking cues) has been linked to lower cessation outcomes. Cessation attempts among Blacks may be compromised by attentional bias to smoking cues and a cue-rich environment. Attention to smoking cues in Black and White smokers was examined in 2 studies. In both studies, assessments were completed during 2 laboratory visits: a nonabstinent session and an abstinent session. In study 1, nontreatment-seeking smokers (99 Whites, 104 Blacks) completed the Subjective Attentional Bias Questionnaire (SABQ; a self-report measure of attention to cues) and the Smoking Stroop task (a reaction time measure of attentional bias to smoking cues). In study 2, 110 White and 74 Black treatment-seeking smokers completed these assessments and attempted to quit. In study 1, Blacks reported higher ratings than Whites on the SABQ (p = .005). In study 2, Blacks also reported higher ratings than Whites on the SABQ (p = .003). In study 2, Blacks had lower biochemical-verified point prevalence abstinence than Whites, and the between-race difference in outcome was partially mediated by SABQ ratings. Blacks reported greater attention to smoking cues than Whites, possibly due to between-race differences in environments. Greater attention to smoking cues may undermine cessation attempts. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Smoking, the oral contraceptive pill, and Crohn's disease.

    Science.gov (United States)

    Wakefield, A J; Sawyerr, A M; Hudson, M; Dhillon, A P; Pounder, R E

    1991-08-01

    Both cigarette smoking and the oral contraceptive pill have been implicated as aggravating factors in Crohn's disease. Based upon the recent demonstration of multifocal gastrointestinal infarction in Crohn's disease, a possible pathogenic mechanism for this condition, we propose how smoking and the oral contraceptive pill may potentiate a tendency for focal thrombosis and hence exacerbate the activity of Crohn's disease.

  1. Cigarette smoking disparities among sexual minority cancer survivors

    Directory of Open Access Journals (Sweden)

    Charles Kamen

    2015-01-01

    Conclusion: The current study offers preliminary evidence that sexual minority status is one variable among many that must be taken into account when assessing health behaviors post-cancer diagnosis. Future research should identify mechanisms leading from sexual minority status to increased rates of smoking and develop tailored smoking cessation interventions.

  2. Smoking and alcohol intervention before surgery: evidence for best practice

    DEFF Research Database (Denmark)

    Tønnesen, H; Nielsen, P R; Lauritzen, J B

    2009-01-01

    Smoking and hazardous drinking are common and important risk factors for an increased rate of complications after surgery. The underlying pathophysiological mechanisms include organic dysfunctions that can recover with abstinence. Abstinence starting 3-8 weeks before surgery will significantly...... smoking and hazardous drinking, and interventions appropriate for the surgical setting applied....

  3. The role of environmental smoking in smoking-related cognitions and susceptibility to smoking in never-smoking 9-12 year-old children

    NARCIS (Netherlands)

    Schuck, K.; Otten, R.; Engels, R.C.M.E.; Kleinjan, M.

    2012-01-01

    Environmental smoking has numerous adverse effects on child health, and children are frequently exposed to environmental smoking. In the present study, we investigated the role of environmental smoking (parental smoking, sibling smoking, peer smoking) in smoking-related cognitions (pros of smoking,

  4. Promoting smoking cessation among parents: effects on smoking-related cognitions and smoking initiation in children.

    Science.gov (United States)

    Schuck, Kathrin; Otten, Roy; Kleinjan, Marloes; Bricker, Jonathan B; Engels, Rutger C M E

    2015-01-01

    Parental smoking is associated with an increased risk of smoking among youth. Epidemiological research has shown that parental smoking cessation can attenuate this risk. This study examined whether telephone counselling for parents and subsequent parental smoking cessation affect smoking-related cognitions and smoking initiation among children of smoking parents. Data of a two-arm randomized controlled trial were used in which 512 smoking parents were recruited into cessation support through their children's primary schools. After the baseline assessment, smoking parents were randomly assigned to tailored telephone counselling or a standard self-help brochure. Parental cessation was measured as 6-month prolonged abstinence at the 12-month follow-up. Children's smoking-related cognitions and smoking initiation were examined at 3-month, 12-month, and 30-month follow-up. No statistical evidence was found that children of parents who received telephone counselling tailored to smoking parents or children of parents who achieved prolonged abstinence differ in smoking-related cognitions (i.e., smoking outcome expectancies, perceived safety of smoking, self-efficacy to refrain from smoking, susceptibility to smoking) or smoking initiation rate on any follow-up assessment. This study is the first to examine the effects of an evidence-based smoking cessation treatment for parents and treatment-induced parental smoking cessation on cognitive and behavioural outcomes among children. Although descriptive statistics showed lower smoking initiation rates among children of parents who achieved prolonged abstinence, there was no statistical evidence that telephone counselling tailored to parents or treatment-induced parental smoking cessation affects precursors of smoking or smoking initiation among youth. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Parental tobacco smoke exposure: Epigenetics and the ...

    Science.gov (United States)

    Epigenetic programming is an important mechanism underlying the Developmental Origins of Health and Disease (DOHaD). Much of the research in this area has focused on maternal nutrition. Parental smoking has emerged as a prime example of how exposure to environmental toxicants during the preconceptional and in utero periods can have long-term effects on offspring health, and the role of the epigenome in these effects. Maternal smoking and exposure to second-hand smoke during pregnancy result in lower birth weight of offspring, and there is now clear evidence that these offspring are at elevated risk for overweight/obesity, type-2 diabetes, respiratory effects during adolescence and adulthood, and may be programmed for increased risk of nicotine addiction. Epigenetic analyses of placenta, cord blood and offspring buccal cells have consistently revealed altered DNA methylation of genes involved in developmental processes and xenobiotic metabolism, and these epigenetic changes are persistent. Animal studies with cigarette smoke and nicotine support these findings. Paternal preconceptional smoking has been positively related to childhood cancers, potentially linked to changes in the sperm epigenome. Germ cell specification and preimplantation development are periods of widespread erasure and reprogramming of DNA methylation, and as such are likely to be sensitive periods for environmental effects on the epigenome. Exposure to tobacco smoke during gametogenesis and in

  6. Smoking and respiratory irregularity in panic disorder.

    Science.gov (United States)

    Caldirola, Daniela; Bellodi, Laura; Cammino, Stefania; Perna, Giampaolo

    2004-09-15

    The biological mechanisms underlying the link between smoking and panic attacks are unknown. Smoking might increase the risk of panic by impairing respiratory system function. We evaluated the effect of smoking on respiratory irregularity in patients with panic disorder (PD) and healthy comparison subjects and the role of the respiratory disorders in this effect. We applied the Approximate Entropy index (ApEn), a nonlinear measure of irregularity, to study breath-by-breath baseline respiratory patterns in our sample. Both smoker and nonsmoker patients had more irregular respiratory patterns than healthy subjects. Smoker patients showed higher ApEn indices of baseline respiratory rate and tidal volume than nonsmoker patients (R = 5.4, df = 2,55, p smoking in healthy subjects did not influence the regularity of respiratory patterns. Respiratory disorders did not account for the influence of smoking on respiratory irregularity. Smokers had more severe panic attacks than nonsmokers. Smoking may impair vulnerable respiratory function and act as disruptive factor on intrinsic baseline respiratory instability in patients with PD, possibly influencing the onset or maintenance of the disorder.

  7. Pathologic Cellular Events in Smoking-Related Pancreatitis

    Energy Technology Data Exchange (ETDEWEB)

    Thrower, Edwin [Department of Internal Medicine, Section of Digestive Diseases, Yale University School of Medicine, New Haven, CT 06520 (United States); Veterans Affairs Connecticut Healthcare, West Haven, CT 06516 (United States)

    2015-04-29

    Pancreatitis, a debilitating inflammatory disorder, results from pancreatic injury. Alcohol abuse is the foremost cause, although cigarette smoking has recently surfaced as a distinct risk factor. The mechanisms by which cigarette smoke and its toxins initiate pathological cellular events leading to pancreatitis, have not been clearly defined. Although cigarette smoke is composed of more than 4000 compounds, it is mainly nicotine and the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), which have been extensively studied with respect to pancreatic diseases. This review summarizes these research findings and highlights cellular pathways which may be of relevance in initiation and progression of smoking-related pancreatitis.

  8. Typology of Clean Development Mechanism project in the nuclear power generation sector; Tipologia de projeto de CDM (Clean Development Mechanism) no setor nucleoeletrico

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Everton de Almeida [Industrias Nucleares Brasileiras (INB), Rio de Janeiro, RJ (Brazil)

    2002-07-01

    This work, facing the Brazilian energetic conditions under the government directives, and the electric sector, suggests a typology of nuclear Clean Development Mechanism, of international cooperation, in the frame of the efforts susceptible to be developed reaching the reduction of the gaseous emissions responsible for the global heating. Other aspects related to technical, legal and market aspects are analysed and proposed.

  9. Comparison of opportunities to respond and generation effect as potential causal mechanisms for incremental rehearsal with multiplication combinations.

    Science.gov (United States)

    Zaslofsky, Anne F; Scholin, Sarah E; Burns, Matthew K; Varma, Sashank

    2016-04-01

    Incremental rehearsal (IR) is an intervention with demonstrated effectiveness in increasing retention of information, yet little is known about how specific intervention components contribute to the intervention's effectiveness. The purpose of this study was to further the theoretical understanding of the intervention by comparing the effects of opportunities to respond (OTR) and generation demand on retention of multiplication combinations. Using a between subject 2 × 2 factorial design, 103 4th and 5th grade students were taught seven multiplication combinations using one of four versions of IR that orthogonally varied OTR (high versus low) and generation demands (high versus low). A two-way ANOVA revealed main effects for OTR, generation demands, and an interaction of the two factors. The effect of generation demands was large (d=1.31), whereas the overall effect of OTR was moderate (d=0.66). Critically, the two factors interacted, with the largest learning gains observed when OTR and generation demands were both high. The results of this study suggest that generation demand is an important factor in the effectiveness of rehearsal interventions. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  10. The moderating role of parental smoking on their children's attitudes toward smoking among a predominantly minority sample: a cross-sectional analysis

    Directory of Open Access Journals (Sweden)

    Prokhorov Alexander V

    2008-07-01

    Full Text Available Abstract Background In general having a parent who smokes or smoked is a strong and consistent predictor of smoking initiation among their children while authoritative parenting style, open communication that demonstrates mutual respect between child and parent, and parental expectations not to smoke are protective. It has been hypothesized that parental smoking affects their children's smoking initiation through both imitation of the behavior and effects on attitudes toward smoking. The goals of the current analysis were to examine these two potential mechanisms. Methods In 2003, 1,417 high school students in Houston, Texas, completed a cross-sectional survey as part of the evaluation of an interactive smoking prevention and cessation program delivered via CD-ROM. To assess the relationship between number of parents who currently smoke and children's smoking status, we completed an unconditional logistic regression. To determine whether the attitudes that children of smokers hold toward smoking are significantly more positive than the attitudes of children of non-smokers we examined whether the parents smoking status moderated the relationship between children's attitudes toward smoking and their ever smoking using unconditional logistic regressions. Results Compared to participants whose parents did not currently smoke, participants who reported one or both parents currently smoke, had increased odds of ever smoking (OR = 1.31; 95% CI: 1.03–1.68; Wald χ2 = 4.78 (df = 1 p = 0.03 and OR = 2.16; 95% CI: 1.51–3.10; Wald χ2 = 17.80 (df = 1 p 2 = 54.71 (df = 1 p 2 = 26.45 (df = 1 p Conclusion Children of smokers were more likely to smoke and reported more favorable attitudes toward smoking compared to children of non-smokers. One interpretation of our findings is that parental smoking not only directly influences behavior; it also moderates their children's attitudes towards smoking and thereby impacts their children's behavior. Our results

  11. WIC providers' perspectives on offering smoking cessation interventions.

    Science.gov (United States)

    Aquilino, Mary Lober; Goody, Cynthia M; Lowe, John B

    2003-01-01

    To examine the perspectives of WIC clinic providers on offering smoking cessation interventions for pregnant women. Four focus groups consisting of WIC nurses, dietitians, and social workers (N = 25) were conducted at WIC clinics in eastern Iowa. Researchers developed discussion guidelines to determine how WIC providers currently approached pregnant women who smoke cigarettes and what they considered barriers to providing effective smoking cessation interventions. Code mapping was used to analyze focus group discussions. Factors influencing the ability of WIC staff to provide a smoking cessation intervention for pregnant women included available time, clinic priorities, staff approaches to clients, and staff training. In addition, providers expressed concerns about educational materials for clients as well as additional client issues that prevented smoking cessation. The absence of mechanisms to track clinic outcomes related to smoking cessation was also noted. WIC providers have time limitations that may necessitate minimal or low-intensity interventions for smoking cessation, but did not know that such approaches are actually effective. WIC providers require more education about the entire issue of smoking cessation in order to become more proactive in their attempts to help pregnant women quit. Training that enhances self-efficacy and understanding of the impact of smoking on mothers, infants, and children should be initiated to motivate staff to intervene. Another strategy to motivate WIC staff in this regard could be tracking clinic outcomes in helping women to quit smoking or prevent relapse.

  12. Parental smoking and children's attention to smoking cues

    NARCIS (Netherlands)

    Lochbühler, K.C.; Otten, R.; Voogd, H.F.J.M.; Engels, R.C.M.E.

    2012-01-01

    Research has shown that children with smoking parents are more likely to initiate smoking than children with non-smoking parents. So far, these effects have been explained through genetic factors, modelling and norm-setting processes. However, it is also possible that parental smoking affects

  13. GENOTOXICITY OF TOBACCO SMOKE AND TOBACCO SMOKE CONDENSATE: A REVIEW

    Science.gov (United States)

    Genotoxicity of Tobacco Smoke and Tobacco Smoke Condensate: A ReviewAbstractThis report reviews the literature on the genotoxicity of main-stream tobacco smoke and cigarette smoke condensate (CSC) published since 1985. CSC is genotoxic in nearly all systems in which it h...

  14. A methodological inquiry into the evaluation of smoking cessation programmes.

    Science.gov (United States)

    Kaneko, M

    1999-06-01

    This paper examines a methodological controversy and aims to show the advantages of introducing an alternative methodological approach, i.e. the 'scientific realist approach', into evaluation studies on health education programmes for smoking cessation. The methodological difficulties of the existing standard evaluation model, i.e. the quasi-experimental approach, are examined. This model fails to investigate how the programme setting influences outcomes (context problem) and draws attention away from understanding why programmes work because it adopts a 'successionist' logic (causation problem). An alternative methodology, the scientific realist approach, is proposed in order to cope with such problems. This approach adopts the 'generative' logic which looks at the matter of causation internally. This logic posits that the working of underlying mechanisms within a more basic level of reality causes relationships between visible events. According to the scientific realist approach, the actual outcomes of smoking cessation programmes follow from the workings of potential mechanisms whose functioning is afforded by contexts conducive to their operation.

  15. Alcohol, smoking and benign hepato-biliary disease

    DEFF Research Database (Denmark)

    Shabanzadeh, Daniel Mønsted; Novovic, Srdan

    2017-01-01

    through effects on bile cholesterol metabolism, the enterohepatic circulation, and gallbladder function. The impact of smoking on gallstone formation seems minor. Both alcohol intake and smoking do not alter the clinical course of gallstone disease carriers. Cholecystectomy is the preferred treatment...... for symptomatic gallstone disease. Studies about the impact of alcohol and smoking on the post-cholecystectomy state are few and future studies should be performed. Pancreatitis is associated with both excessive alcohol intake and smoking in observational studies. Interpretation of associations with pancreatitis...... is hampered by an incomplete understanding of underlying mechanisms and by the co-existence of excessive alcohol intake and smoking. Smoking cessation and alcohol abstinence is recommended in the treatment of pancreatitis, but higher-level evidence is needed....

  16. Goal-independent mechanisms for free response generation: creative and pseudo-random performance share neural substrates.

    Science.gov (United States)

    de Manzano, Örjan; Ullén, Fredrik

    2012-01-02

    To what extent free response generation in different tasks uses common and task-specific neurocognitive processes has remained unclear. Here, we investigated overlap and differences in neural activity during musical improvisation and pseudo-random response generation. Brain activity was measured using fMRI in a group of professional classical pianists, who performed musical improvisation of melodies, pseudo-random key-presses and a baseline condition (sight-reading), on either two, six or twelve keys on a piano keyboard. The results revealed an extensive overlap in neural activity between the two generative conditions. Active regions included the dorsolateral and dorsomedial prefrontal cortices, inferior frontal gyrus, anterior cingulate cortex and pre-SMA. No regions showed higher activity in improvisation than in pseudo-random generation. These findings suggest that the activated regions fulfill generic functions that are utilized in different types of free generation tasks, independent of overall goal. In contrast, pseudo-random generation was accompanied by higher activity than improvisation in several regions. This presumably reflects the participants' musical expertise as well as the pseudo-random generation task's high load on attention, working memory, and executive control. The results highlight the significance of using naturalistic tasks to study human behavior and cognition. No brain activity was related to the size of the response set. We discuss that this may reflect that the musicians were able to use specific strategies for improvisation, by which there was no simple relationship between response set size and neural activity. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Cardiovascular effects of secondhand smoke: nearly as large as smoking.

    Science.gov (United States)

    Barnoya, Joaquin; Glantz, Stanton A

    2005-05-24

    Secondhand smoke increases the risk of coronary heart disease by approximately 30%. This effect is larger than one would expect on the basis of the risks associated with active smoking and the relative doses of tobacco smoke delivered to smokers and nonsmokers. We conducted a literature review of the research describing the mechanistic effects of secondhand smoke on the cardiovascular system, emphasizing research published since 1995, and compared the effects of secondhand smoke with the effects of active smoking. Evidence is rapidly accumulating that the cardiovascular system--platelet and endothelial function, arterial stiffness, atherosclerosis, oxidative stress, inflammation, heart rate variability, energy metabolism, and increased infarct size--is exquisitely sensitive to the toxins in secondhand smoke. The effects of even brief (minutes to hours) passive smoking are often nearly as large (averaging 80% to 90%) as chronic active smoking. The effects of secondhand smoke are substantial and rapid, explaining the relatively large risks that have been reported in epidemiological studies.

  18. Generating Autoclave-Level Mechanical Properties with Out-of-Autoclave Thermoplastic Placement of Large Composite Aerospace Structures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Out-of-autoclave thermoplastic tape/tow placement (TP-ATP) is nearing commercialization but suffers a moderate gap in mechanical properties compared with laminates...

  19. Generating Autoclave-Level Mechanical Properties with Out-of-Autoclave Thermoplastic Placement of Large Composite Aerospace Structures, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Out-of-autoclave thermoplastic tape/tow placement (TP-ATP) is nearing commercialization but suffers a moderate gap in mechanical properties compared with laminates...

  20. Hydrogen Generation from Ammonia Borane and Water Through the Combustion Reactions with Mechanically Alloyed Al/Mg Powder

    Science.gov (United States)

    2014-08-11

    mechanisms during combustion of these mixtures. For this purpose, isotopic tests, involving use of heavy water and mass-spectroscopy of gaseous combustion...Comparison of hydrogen release from various boron -based chemical hydrides (8)....................7 Figure 2. Comparison of hydrogen release from...acquired from the pressure increase. Isotopic tests (deuterium) were used for revealing the reaction mechanisms. CHAPTER 2: LITERATURE REVIEW 2.1