Aluminum gallium nitride (GaN)/GaN high electron mobility transistor-based sensors for glucose detection in exhaled breath condensate.

Science.gov (United States)

Chu, Byung Hwan; Kang, Byoung Sam; Hung, Sheng Chun; Chen, Ke Hung; Ren, Fan; Sciullo, Andrew; Gila, Brent P; Pearton, Stephen J

2010-01-01

Immobilized aluminum gallium nitride (AlGaN)/GaN high electron mobility transistors (HEMTs) have shown great potential in the areas of pH, chloride ion, and glucose detection in exhaled breath condensate (EBC). HEMT sensors can be integrated into a wireless data transmission system that allows for remote monitoring. This technology offers the possibility of using AlGaN/GaN HEMTs for extended investigations of airway pathology of detecting glucose in EBC without the need for clinical visits. HEMT structures, consisting of a 3-microm-thick undoped GaN buffer, 30-A-thick Al(0.3)Ga(0.7)N spacer, and 220-A-thick silicon-doped Al(0.3)Ga(0.7)N cap layer, were used for fabricating the HEMT sensors. The gate area of the pH, chloride ion, and glucose detection was immobilized with scandium oxide (Sc(2)O(3)), silver chloride (AgCl) thin film, and zinc oxide (ZnO) nanorods, respectively. The Sc(2)O(3)-gated sensor could detect the pH of solutions ranging from 3 to 10 with a resolution of approximately 0.1 pH. A chloride ion detection limit of 10(-8) M was achieved with a HEMT sensor immobilized with the AgCl thin film. The drain-source current of the ZnO nanorod-gated AlGaN/GaN HEMT sensor immobilized with glucose oxidase showed a rapid response of less than 5 seconds when the sensor was exposed to the target glucose in a buffer with a pH value of 7.4. The sensor could detect a wide range of concentrations from 0.5 nM to 125 microM. There is great promise for using HEMT-based sensors to enhance the detection sensitivity for glucose detection in EBC. Depending on the immobilized material, HEMT-based sensors can be used for sensing different materials. These electronic detection approaches with rapid response and good repeatability show potential for the investigation of airway pathology. The devices can also be integrated into a wireless data transmission system for remote monitoring applications. This sensor technology could use the exhaled breath condensate to measure the

Breath biomarkers in toxicology.

Science.gov (United States)

Pleil, Joachim D

2016-11-01

Exhaled breath has joined blood and urine as a valuable resource for sampling and analyzing biomarkers in human media for assessing exposure, uptake metabolism, and elimination of toxic chemicals. This article focuses current use of exhaled gas, aerosols, and vapor in human breath, the methods for collection, and ultimately the use of the resulting data. Some advantages of breath are the noninvasive and self-administered nature of collection, the essentially inexhaustible supply, and that breath sampling does not produce potentially infectious waste such as needles, wipes, bandages, and glassware. In contrast to blood and urine, breath samples can be collected on demand in rapid succession and so allow toxicokinetic observations of uptake and elimination in any time frame. Furthermore, new technologies now allow capturing condensed breath vapor directly, or just the aerosol fraction alone, to gain access to inorganic species, lung pH, proteins and protein fragments, cellular DNA, and whole microorganisms from the pulmonary microbiome. Future applications are discussed, especially the use of isotopically labeled probes, non-targeted (discovery) analysis, cellular level toxicity testing, and ultimately assessing "crowd breath" of groups of people and the relation to dose of airborne and other environmental chemicals at the population level.

Determination of cysteinyl leukotrienes in exhaled breath condensate: Method combining immunoseparation with LC-ESI-MS/MS

Czech Academy of Sciences Publication Activity Database

Syslová, K.; Kačer, P.; Vilhanová, B.; Kuzma, Marek; Lipovová, P.; Fenclová, Z.; Lebedová, J.; Pelclová, D.

2011-01-01

Roč. 879, č. 23 (2011), s. 2220-2228 ISSN 1570-0232 R&D Projects: GA MZd NS10298 Keywords : Cysteinyl leukotriene * Exhaled breath condensate * Immunoseparation Subject RIV: CE - Biochemistry Impact factor: 2.888, year: 2011

Leukotrienes in Exhaled Breath Condensate and Fractional Exhaled Nitric Oxide in Workers Exposed to TiO2 Nanoparticles.

Czech Academy of Sciences Publication Activity Database

Pelclová, D.; Ždímal, Vladimír; Kačer, P.; Felclová, Z.; Vlčková, Š.; Komarc, M.; Navrátil, Tomáš; Schwarz, Jaroslav; Zíková, Naděžda; Makeš, Otakar; Syslová, K.; Běláček, J.; Zakharov, S.

2016-01-01

Roč. 10, č. 3 (2016), s. 036004 ISSN 1752-7155 Institutional support: RVO:67985858 ; RVO:61388955 Keywords : nanoparticles * TiO2 * exhaled breath condensate Subject RIV: CF - Physical ; Theoretical Chemistry; CG - Electrochemistry (UFCH-W) Impact factor: 4.318, year: 2016

L-arginine supplementation enhances exhaled NO, breath condensate VEGF, and headache at 4,342 m.

Science.gov (United States)

Mansoor, Jim K; Morrissey, Brian M; Walby, William F; Yoneda, Ken Y; Juarez, Maya; Kajekar, Radhika; Severinghaus, John W; Eldridge, Marlowe W; Schelegle, Edward S

2005-01-01

We examined the effect of dietary supplementation with L-arginine on breath condensate VEGF, exhaled nitric oxide (NO), plasma erythropoietin, symptoms of acute mountain sickness, and respiratory related sensations at 4,342 m through the course of 24 h in seven healthy male subjects. Serum L-arginine levels increased in treated subjects at time 0, 8, and 24 h compared with placebo, indicating the effectiveness of our treatment. L-arginine had no significant effect on overall Lake Louise scores compared with placebo. However, there was a significant increase in headache within the L-arginine treatment group at 12 h compared with time 0, a change not seen in the placebo condition between these two time points. There was a trend (p = 0.087) toward greater exhaled NO and significant increases in breath condensate VEGF with L-arginine treatment, but no L-arginine effect on serum EPO. These results suggest that L-arginine supplementation increases HIF-1 stabilization in the lung, possibly through a NO-dependent pathway. In total, our observations indicate that L-arginine supplementation is not beneficial in the prophylactic treatment of AMS.

Exhaled breath condensate nitrates, but not nitrites or FENO, relate to asthma control.

Science.gov (United States)

Malinovschi, Andrei; Pizzimenti, Stefano; Sciascia, Savino; Heffler, Enrico; Badiu, Iuliana; Rolla, Giovanni

2011-07-01

Asthma is a chronic respiratory disease, characterised by airways inflammation, obstruction and hyperresponsiveness. Asthma control is the goal of asthma treatment, but many patients have sub-optimal control. Exhaled NO and exhaled breath condensate (EBC) NO metabolites (nitrites and nitrates) measurements are non-invasive tools to assess airways inflammation. Our aim was to investigate the relationships between asthma control and the above-named biomarkers of airways inflammation. Thirty-nine non-smoking asthmatic patients (19 women) aged 50 (21-80) years performed measurements of exhaled NO (FENO), EBC nitrates, nitrites and pH, and answered Asthma Control Questionnaire (ACQ) and Asthma Control Test (ACT)-questionnaire. The ACT and ACQ score were strongly interrelated (ρ = -0.84, p 0.05). EBC nitrates were negatively related to ACT score (ρ = -0.34, p = 0.03) and positively related to ACQ score (ρ = 0.41, p = 0.001) while no relation of EBC nitrites to either ACQ or ACT score was found (p>0.05). EBC nitrates were the only biomarker that was significantly related to asthma control. This suggests that nitrates, but not nitrites or FENO, reflect an aspect of airways inflammation that is closer related to asthma symptoms. Therefore there is a potential role for EBC nitrates in objective assessment of asthma control. Copyright © 2010 Elsevier Ltd. All rights reserved.

Diagnostic value of a pattern of exhaled breath condensate biomarkers in asthmatic children.

Science.gov (United States)

Maloča Vuljanko, I; Turkalj, M; Nogalo, B; Bulat Lokas, S; Plavec, D

Diagnosing asthma in children is a challenge and using a single biomarker from exhaled breath condensate (EBC) showed the lack of improvement in it. The aim of this study was to assess the diagnostic potential of a pattern of simple chemical biomarkers from EBC in diagnosing asthma in children in a real-life setting, its association with lung function and gastroesophageal reflux disease (GERD). In 75 consecutive children aged 5-7 years with asthma-like symptoms the following tests were performed: skin prick tests, spirometry, impulse oscillometry (IOS), exhaled NO (F E NO), 24-hour oesophageal pH monitoring and EBC collection with subsequent analysis of pH, carbon dioxide tension, oxygen tension, and concentrations of magnesium, calcium, iron and urates. No significant differences were found for individual EBC biomarkers between asthmatics and non-asthmatics (p>0.05 for all). A pattern of six EBC biomarkers showed a statistically significant (p=0.046) predictive model for asthma (AUC=0.698, PPV=84.2%, NPV=38.9%). None to moderate association (R 2 up to 0.43) between EBC biomarkers and lung function measures and F E NO was found, with IOS parameters showing the best association with EBC biomarkers. A significantly higher EBC Fe was found in children with asthma and GERD compared to asthmatics without GERD (p=0.049). An approach that involves a pattern of EBC biomarkers had a better diagnostic accuracy for asthma in children in real-life settings compared to a single one. Poor to moderate association of EBC biomarkers with lung function suggests a complementary value of EBC analysis for asthma diagnosis in children. Copyright © 2016 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

Markers of Lipid Oxidative Damage in the Exhaled Breath Condensate of Nano TiO2 Production Workers.

Czech Academy of Sciences Publication Activity Database

Pelclová, D.; Ždímal, Vladimír; Kačer, P.; Zíková, Naděžda; Komarc, M.; Fenclová, Z.; Vlčková, Š.; Schwarz, Jaroslav; Makeš, Otakar; Syslová, K.; Navrátil, Tomáš; Turci, F.; Corazzari, I.; Zakharov, S.; Bello, D.

2017-01-01

Roč. 11, č. 1 (2017), s. 52-63 ISSN 1743-5390 R&D Projects: GA ČR(CZ) GBP503/12/G147 Institutional support: RVO:67985858 ; RVO:61388955 Keywords : exhaled breath condensate * aldehydes * oxidative stress * occupational exposure * monitoring Subject RIV: DN - Health Impact of the Environment Quality; CF - Physical ; Theoretical Chemistry (UFCH-W) OBOR OECD: Public and environmental health; Physical chemistry (UFCH-W) Impact factor: 6.428, year: 2016

Bioanalysis of underivatized amino acids in non-invasive exhaled breath condensate samples using liquid chromatography coupled with tandem mass spectrometry.

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Konieczna, Lucyna; Pyszka, Magdalena; Okońska, Magdalena; Niedźwiecki, Maciej; Bączek, Tomasz

2018-03-23

Exhaled breath condensate (EBC) is receiving increased attention as a novel, entirely non-invasive technique for collecting biomarker samples. This increased attention is due to the fact that EBC is simple, effort independent, rapid, can be repeated frequently, and can be performed on young children and patients suffering from a variety of diseases. By having a subject breathe tidally through a cooling system for 15-20 min, a sufficient amount of condensate is collected for analysis of biomarkers in clinical studies. However, bioanalysis of EBC involves an unavoidable sample preparation step due to the low concentration of its components. Thus, there is a need for a new and more sensitive analytical method of assessing EBC samples. While researchers have considered analyses of single and small quantities of amino acids - for example, those connected with leukemia - no one has previously attempted to simultaneously analyze a panel of 23 amino acids. Moreover, the present study is well-justified, as prior studies focusing on single amino acids and leukemia at the moment of diagnosis and during chemotherapy (33 days of treatment) are inconsistent. In the present study, amino acids were separated using an XBridge Amide column (3 mm × 100 mm, 3.5 μm). The mobile phase consisted of 10 mM of ammonium buffer in water with a pH of 3 (Phase A) and 10 mM ammonium buffer in acetonitrile (Phase B) under gradient program elution. The analytes were detected in electrospray positive ionization mode. Under optimal conditions, the proposed method exhibited limits of quantification (LOQ) in the range of 0.05-0.5 ng/mL, and good linearity, with the determination coefficient (R 2 ) falling between 0.9904 and 0.9998. The accuracy in human exhaled breath condensate samples ranged between 93.3-113.3% for the 23 studied amino acids, with intra- and inter-day coefficient of variation (CVs) of 0.13-9.92% and 0.17-10.53%, respectively. To demonstrate the liquid

Oxidative Stress Markers Are Elevated in Exhaled Breath Condensate of Workers Exposed to Nanoparticles during Iron Oxide Pigment Production.

Czech Academy of Sciences Publication Activity Database

Pelclová, D.; Ždímal, Vladimír; Kačer, P.; Fenclová, Z.; Vlčková, Š.; Syslová, K.; Navrátil, Tomáš; Schwarz, Jaroslav; Zíková, Naděžda; Barošová, H.; Turci, F.; Komarc, M.; Pelcl, T.; Běláček, J.; Kukutschová, J.; Zakharov, S.

2016-01-01

Roč. 10, č. 1 (2016), s. 016004 ISSN 1752-7155 Institutional support: RVO:67985858 ; RVO:61388955 Keywords : nanoparticles * exhaled breath condensate * oxidative stress * urine * occupational exposure * Fe2O3 * Fe3O4 Subject RIV: DN - Health Impact of the Environment Quality; CF - Physical ; Theoretical Chemistry (UFCH-W) Impact factor: 4.318, year: 2016

Leukotrienes B4, C4, D4 and E4 in the Exhaled Breath Condensate (EBC), Blood and Urine in Patients with Pneumoconiosis

Czech Academy of Sciences Publication Activity Database

Pelclová, D.; Fenclová, Z.; Vlčková, Š.; Lebedová, J.; Syslová, K.; Pecha, O.; Běláček, J.; Navrátil, Tomáš; Kuzma, Marek; Kačer, P.

2012-01-01

Roč. 50, č. 4 (2012), s. 299-306 ISSN 0019-8366 Institutional support: RVO:61388955 ; RVO:61388971 Keywords : leukotrienes * Lung fibrosis * exhaled breath condensate Subject RIV: CG - Electrochemistry Impact factor: 0.870, year: 2012

Electret filter collects more exhaled albumin than glass condenser

Science.gov (United States)

Jia, Ziru; Liu, Hongying; Li, Wang; Xie, Dandan; Cheng, Ke; Pi, Xitian

2018-01-01

Abstract In recent years, noninvasive diagnosis based on biomarkers in exhaled breath has been extensively studied. The procedure of biomarker collection is a key step. However, the traditional condenser method has low efficacy in collecting nonvolatile compounds especially the protein biomarkers in breath. To solve this deficiency, here we propose an electret filter method. Exhaled breath of 6 volunteers was collected with a glass condenser and an electret filter. The amount of albumin was analyzed. Furthermore, the difference of exhaled albumin between smokers and nonsmokers was evaluated. The electret filter method collected more albumin than the glass condenser method at the same breath volume level (P albumin than nonsmokers were also observed (P albumin than nonsmokers. PMID:29384875

MicroRNA7 expression in exhaled breath condensate of smokers with chronic obstructive pulmonary disease: A potential biomarker?

OpenAIRE

Nevine Abd Elfattah; R. Ali-Labib

2017-01-01

Rationale: The global burden of lung cancer is attributed to its poor outcome as it is usually discovered in an advanced stage therefore the constant search for screening protocols among the high risk groups like smokers and chronic obstructive pulmonary disease (COPD). Biomarker testing in exhaled breath condensate (EBC) samples is a simple inexpensive non invasive method. Many previous researches linked the dys-Regulation of microRNAs to the development of lung carcinogenesis. Consequently ...

Fractionated breath condensate sampling: H2O2 concentrations of the alveolar fraction may be related to asthma control in children

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Trischler Jordis

2012-02-01

Full Text Available Abstract Background Asthma is a chronic inflammatory disease of the airways but recent studies have shown that alveoli are also subject to pathophysiological changes. This study was undertaken to compare hydrogen peroxide (H2O2 concentrations in different parts of the lung using a new technique of fractioned breath condensate sampling. Methods In 52 children (9-17 years, 32 asthmatic patients, 20 controls measurements of exhaled nitric oxide (FENO, lung function, H2O2 in exhaled breath condensate (EBC and the asthma control test (ACT were performed. Exhaled breath condensate was collected in two different fractions, representing mainly either the airways or the alveoli. H2O2 was analysed in the airway and alveolar fractions and compared to clinical parameters. Results The exhaled H2O2 concentration was significantly higher in the airway fraction than in the alveolar fraction comparing each single pair (p = 0.003, 0.032 and 0.040 for the whole study group, the asthmatic group and the control group, respectively. Asthma control, measured by the asthma control test (ACT, correlated significantly with the H2O2 concentrations in the alveolar fraction (r = 0.606, p = 0.004 but not with those in the airway fraction in the group of children above 12 years. FENO values and lung function parameters did not correlate to the H2O2 concentrations of each fraction. Conclusion The new technique of fractionated H2O2 measurement may differentiate H2O2 concentrations in different parts of the lung in asthmatic and control children. H2O2 concentrations of the alveolar fraction may be related to the asthma control test in children.

Nitrites and nitrates in exhaled breath condensate in cystic fibrosis: relation to clinical parameters.

Science.gov (United States)

Fila, L; Chladek, J; Maly, M; Musil, J

2013-01-01

To evaluate correlation of exhaled breath condensate (EBC) nitrite and nitrate concentrations with disease severity in cystic fibrosis (CF) patients. Nitrites and nitrates are products of oxidative metabolism of nitric oxide. Impaired metabolism of nitric oxide plays a role in pathogenesis of CF. EBC was collected from 46 stable CF patients and from 21 healthy controls. EBC concentrations of nitrites and nitrates were correlated with parameters of lung disease and nutritional status and with systemic inflammatory markers. EBC nitrates concentrations in CF patients were lower than in healthy subjects (5.8 vs 14.3 μmol/l, pnitrates concentrations correlate with disease severity in CF patients and are lower than in healthy subjects (Tab. 4, Fig. 1, Ref. 48).

Hydrogen peroxide release and acid-base status in exhaled breath condensate at rest and after maximal exercise in young, healthy subjects.

Science.gov (United States)

Marek, E; Platen, P; Volke, J; Mückenhoff, K; Marek, W

2009-12-07

Exhaled breath condensate (EBC) contains among a large number of mediators hydrogen peroxide (H2O2) as a marker of airway inflammation and oxidative stress. Similarly EBC pH also changes in respiratory diseases. It was the aim of our investigation to prove if hydrogen peroxide release and changes in pH of EBC changes with exercise. EBC was collected from 100 litres exhaled air along with samples of arterialized blood of 16 healthy subjects (9 males, 7 females, age 23 +/- 1 years). EBC hydrogen peroxide was analyzed with EcoCheck amperometer (FILT, Berlin). The rate of H(2)O(2) release was calculated from the concentration and collection time. pH and PCO(2) in blood and in EBC were measured with the Radiometer blood gas analyzer, EBC was equilibrated with a gas mixture (5% CO(2) in O(2)). The bicarbonate concentration was calculated according to the law of mass action for CO(2) and HCO(3)(-) (pK = 6.1). H(2)O(2) concentration in EBC was 190 +/- 109 nmol/l, and H (2)O(2) release at rest was 31.0 +/- 18.3 pmol/min. At maximal exercise, the H(2)O(2) concentration in EBC increased to 250 +/- 120 nmol/l, and H(2)O(2) release significantly increased at maximal exercise to 84.4 +/- 39.9 pmol/min (Pexercise, pH 6.18 +/- 0.17 and [HCO(3)(-)] 1.23 +/- 0.30 mmol/l remained almost unaltered. The rate of H(2)O(2) release in EBC increased during exhausting exercise (external load: 300 Watt) by a factor of 2, whereas the pH and the bicarbonate concentration of the EBC, equilibrated with 5% CO(2) at 37 degrees C were not significantly altered. It has to be proven by further experiments whether there is a linear relationship between the rates of H(2)O(2) release in EBC in graded submaximal exercise.

Breath condensate levels of 8-isoprostane and leukotriene B4 after ozone inhalation are greater in sensitive versus nonsensitive subjects.

Science.gov (United States)

Alfaro, Mario F; Walby, William F; Adams, William C; Schelegle, Edward S

2007-01-01

Ozone (O3) inhalation induces pulmonary function decrements and inflammation. The present study was designed to determine if a relationship exists between O3 induced pulmonary function changes and the presence of inflammatory markers as measured in exhaled breath condensates (EBCs) obtained from O3-sensitive and nonsensitive human subjects. Eight healthy adult volunteers (4 males/4 females, age 18 to 30 years) were studied, characterized as to their ozone sensitivity and placed into 2 groups (sensitive and nonsensitive) with each group having 2 males and 2 females. Subjects completed a 20-minute EBC collection and pulmonary function test (PFT) prior to a single 60-minute bout of cycle ergometer exercise (V(E) = 50-55 L/min) while breathing filtered air (FA) or 0.35 ppm O3. Subjective symptom scores (SSSs) were collected at 6, 20, 40, and 60 minutes during exposure. An immediate postexposure PFT was performed followed by an EBC collection. Subjective symptom scores, EBCs, and PFTs were collected at 1, 4 and 8 hours post exposure. EBCs were analyzed for prostaglandin E2 (PGE2), leukotriene B4 (LTB4), 8-isoprostane, and total nitric oxide (NO) metabolites (nitrate + nitrite content). Sensitive subjects, breathing O3, had significantly greater functional decrements in PFTs, increased SSSs, and increased rapid shallow breathing as well as elevated levels of 8-isoprostane and LTB4 in EBCs compared to those breathing FA. In addition, there were significant increases in nitrate + nitrite content in both sensitive and nonsensitive subjects breathing O3 compared to FA. These results indicate that sensitive subjects have elevated arachidonic acid metabolites in EBCs compared to nonsensitive subjects after O3 inhalation.

Exploring Airway Diseases by NMR-Based Metabonomics: A Review of Application to Exhaled Breath Condensate

Directory of Open Access Journals (Sweden)

Matteo Sofia

2011-01-01

Full Text Available There is increasing evidence that biomarkers of exhaled gases or exhaled breath condensate (EBC may help in detecting abnormalities in respiratory diseases mirroring increased, oxidative stress, airways inflammation and endothelial dysfunction. Beside the traditional techniques to investigate biomarker profiles, “omics” sciences have raised interest in the clinical field as potentially improving disease phenotyping. In particular, metabonomics appears to be an important tool to gain qualitative and quantitative information on low-molecular weight metabolites present in cells, tissues, and fluids. Here, we review the potential use of EBC as a suitable matrix for metabonomic studies using nuclear magnetic resonance (NMR spectroscopy. By using this approach in airway diseases, it is now possible to separate specific EBC profiles, with implication in disease phenotyping and personalized therapy.

Vapor condensation device

International Nuclear Information System (INIS)

Sakurai, Manabu; Hirayama, Fumio; Kurosawa, Setsumi; Yoshikawa, Jun; Hosaka, Seiichi.

1992-01-01

The present invention enables to separate and remove 14 C as CO 3 - ions without condensation in a vapor condensation can of a nuclear facility. That is, the vapor condensation device of the nuclear facility comprises (1) a spray pipe for spraying an acidic aqueous solution to the evaporation surface of an evaporation section, (2) a spray pump for sending the acidic aqueous solution to the spray pipe, (3) a tank for storing the acidic aqueous solution, (4) a pH sensor for detecting pH of the evaporation section, (5) a pH control section for controlling the spray pump, depending on the result of the detection of the pH sensor. With such a constitution, the pH of liquid wastes on the vaporization surface is controlled to 7 by spraying an aqueous solution of dilute sulfuric acid to the evaporation surface, thereby enabling to increase the transfer rate of 14 C to condensates to 60 to 70%. If 14 C is separated and removed as a CO 2 gas from the evaporation surface, the pH of the liquid wastes returns to the alkaline range of 9 to 10 and the liquid wastes are returned to a heating section. The amount of spraying the aqueous solution of dilute sulfuric acid can be controlled till the pH is reduced to 5. (I.S.)

Exercise in cold air and hydrogen peroxide release in exhaled breath condensate.

Science.gov (United States)

Marek, E; Volke, J; Mückenhoff, K; Platen, P; Marek, W

2013-01-01

Athletes have changes in the lung epithelial cells caused by inhalation of cold and dry air. The exhaled breath condensate contains a number of mediators from the respiratory system and H(2)O(2) is described as a marker of airways inflammation. The aim of this study was to determine the influence of exercise combined with cold air on the H(2)O(2) release in the exhaled breath. Twelve males (23.1 ± 1.5 years) were randomly assigned at 2 different days (1 day rest) to perform a 50 min run (75-80% of their max. heart rate) under normal (N) laboratory (18.1 ± 1.1°C) or cold (C) field condition (-15.2 ± 3.1°C). Before and immediately after each run, the EBC was collected under laboratory conditions and was analyzed amperometrically. Prior to the two runs, H(2)O(2) concentrations were 145.0 ± 31.0 (N) and 160.0 ± 49.1 nmol/L (C) and theoretical release was 70.3 ± 37.1 (N) and 82.6 ± 27.1 pmol/min (C) (p > 0.05). After each run, H(2)O(2) concentration increased significantly to 388.0 ± 22.8 nmol/L (N) and 622.1 ± 44.2 nmol/L (C) (p release: 249.2 ± 35.7 pmol/min (N) and 400.9 ± 35.7 pmol/min (C) (p release of H(2)O(2) into the EBC takes place under both resting conditions and after exercise. The concentration and release of H(2)O(2) increased after exercise in cold air compared to resting and laboratory conditions, which points to an increase in inflammatory and oxidative stress.

Hydrogen peroxide release and acid-base status in exhaled breath condensate at rest and after maximal exercise in young, healthy subjects

Directory of Open Access Journals (Sweden)

Marek E

2009-12-01

Full Text Available Abstract Objective Exhaled breath condensate (EBC contains among a large number of mediators hydrogen peroxide (H2O2 as a marker of airway inflammation and oxidative stress. Similarly EBC pH also changes in respiratory diseases. It was the aim of our investigation to prove if hydrogen peroxide release and changes in pH of EBC changes with exercise. Methods EBC was collected from 100 litres exhaled air along with samples of arterialized blood of 16 healthy subjects (9 males, 7 females, age 23 ± 1 years. EBC hydrogen peroxide was analyzed with EcoCheck amperometer (FILT, Berlin. The rate of H2O2 release was calculated from the concentration and collection time. pH and PCO2 in blood and in EBC were measured with the Radiometer blood gas analyzer, EBC was equilibrated with a gas mixture (5% CO2 in O2. The bicarbonate concentration was calculated according to the law of mass action for CO2 and HCO3- (pK = 6.1. Results H2O2 concentration in EBC was 190 ± 109 nmol/l, and H2O2 release at rest was 31.0 ± 18.3 pmol/min. At maximal exercise, the H2O = concentration in EBC increased to 250 ± 120 nmol/l, and H2O2 release significantly increased at maximal exercise to 84.4 ± 39.9 pmol/min (P 2 equilibrated EBC was at 6.08 ± 0.23 and the [HCO3 -] was 1.03 ± 0.40 mmol/l. At maximum exercise, pH 6.18 ± 0.17 and [HCO3-] 1.23 ± 0.30 mmol/l remained almost unaltered. Conclusions The rate of H2O2 release in EBC increased during exhausting exercise (external load: 300 Watt by a factor of 2, whereas the pH and the bicarbonate concentration of the EBC, equilibrated with 5% CO2 at 37°C were not significantly altered. It has to be proven by further experiments whether there is a linear relationship between the rates of H2O2 release in EBC in graded submaximal exercise.

LC-MS/MS Estimation of Propranolol level in Exhaled Breath Condensate

Directory of Open Access Journals (Sweden)

Samin Hamidi 1, Maryam Amini 2, Maryam Khoubnasabjafari 3, Vahid Jouyban-Gharamaleki 4,5, Hossein Sate 6, Abolghasem Jouyban 5,7 *

2017-12-01

Full Text Available Background: Exhaled breath condensate (EBC could be used as a non-invasive and alternative specimen to urine and blood for monitoring propranolol levels. A simple, sensitive and selective liquid chromatography–tandem mass spectrometry (LC–MS/MS method is employed for the determination of propranolol in EBC samples. Methods: Samples directly injected to a C18 analytical column and isocratically separated using a mobile phase composed of methanol + acetic acid (99:1 v/v. Detection was performed by positive electrospray ionization in multiple reaction monitoring and selected ion recording modes. Results: The chromatographic separation was obtained within 6.0 min and was linear over the concentration range of 5.6–224.0 ng/mL (R2 = 0.999. The accuracy and precision of the method were within 15% according to FDA guideline. The found concentrations of propranolol in EBC of two patients receiving 80 mg/day were 30 and 40 ng/mL. Conclusion: Developed method was applied to determine propranolol levels in three patients receiving propranolol in their medication. The obtained propranolol levels in EBC could be used to develop simpler, cheaper and more feasible analytical methods to be used in routine analysis of propranolol in biomedical analytical laboratories.

Breath acidification in adolescent runners exposed to atmospheric pollution: A prospective, repeated measures observational study

Directory of Open Access Journals (Sweden)

Van Sickle David

2008-03-01

Full Text Available Abstract Background Vigorous outdoors exercise during an episode of air pollution might cause airway inflammation. The purpose of this study was to examine the effects of vigorous outdoor exercise during peak smog season on breath pH, a biomarker of airway inflammation, in adolescent athletes. Methods We measured breath pH both pre- and post-exercise on ten days during peak smog season in 16 high school athletes engaged in daily long-distance running in a downwind suburb of Atlanta. The association of post-exercise breath pH with ambient ozone and particulate matter concentrations was tested with linear regression. Results We collected 144 pre-exercise and 146 post-exercise breath samples from 16 runners (mean age 14.9 years, 56% male. Median pre-exercise breath pH was 7.58 (interquartile range: 6.90 to 7.86 and did not change significantly after exercise. We observed no significant association between ambient ozone or particulate matter and post-exercise breath pH. However both pre- and post-exercise breath pH were strikingly low in these athletes when compared to a control sample of 14 relatively sedentary healthy adults and to published values of breath pH in healthy subjects. Conclusion Although we did not observe an acute effect of air pollution exposure during exercise on breath pH, breath pH was surprisingly low in this sample of otherwise healthy long-distance runners. We speculate that repetitive vigorous exercise may induce airway acidification.

[pH values in the pharynx of the patients presenting with compromised nasal breathing of inflammatory and non-inflammatory genesis concomitant with gastroesophageal reflux disease].

Science.gov (United States)

Subbotina, M V; Temnikova, I V; Onuchina, E V

2015-01-01

The objective of the present study was to estimate the influence of gastroesophageal reflux disease (GERD) on the pH values in the pharynx and nose. It included 87 patients at the age varying from 18 to 81 years admitted to the Irkutsk-based Railway Clinical Hospital and allocated to four groups. Group 1 was comprised of 25 patients presenting with gastroesophageal reflux disease and chronic rhinosinusitis (CRS), group 2 consisted of 29 patients with CRS in the absence of GERD, group 3 included 22 patients with nasal septum deformations (NSD) and GERD, group 4 included 11 patients with NSD and motor rhinitis without GERD. The control group was formed from 10 volunteers. pH was measured by the contact method with the use ofEkokhim indicator paper. Gastroesophageal reflux disease was diagnosed following the recommendations of the Montreal consensus. It was shown that pH values in the pharynx of the patients with compromised nasal breathing of any origin in combination with GERD were lower than in the absence of GERD and in the healthy volunteers. The study groups did not differ in terms of pH values in the nasal cavity. It is concluded that pH values 4 or lower may serve as the criterion for pharyngo-laryngeal reflux (PLR) concomitant with HERD while pH 5 occurs more frequently in the patients with compromised nasal breathing of any etiology, regardless of the presence or absence of GERD.Disordered nasal breathing of any genesis in the patients presenting with gastroesophageal reflux disease was associated with the feeling of the lump in the throat, congestion of the respiratory tract and the nose, pain in the ears, cardialgia, and irregular heartbeat. It isrecommended to use pH measurements as a criterion for diagnostics of pharyngo-laryngeal reflux in the patients presenting with gastroesophageal reflux disease.

Observation of Faraday Waves in a Bose-Einstein Condensate

International Nuclear Information System (INIS)

Engels, P.; Atherton, C.; Hoefer, M. A.

2007-01-01

Faraday waves in a cigar-shaped Bose-Einstein condensate are created. It is shown that periodically modulating the transverse confinement, and thus the nonlinear interactions in the BEC, excites small amplitude longitudinal oscillations through a parametric resonance. It is also demonstrated that even without the presence of a continuous drive, an initial transverse breathing mode excitation of the condensate leads to spontaneous pattern formation in the longitudinal direction. Finally, the effects of strongly driving the transverse breathing mode with large amplitude are investigated. In this case, impact-oscillator behavior and intriguing nonlinear dynamics, including the gradual emergence of multiple longitudinal modes, are observed

The analysis of volatile organic compounds in exhaled breath and biomarkers in exhaled breath condensate in children - clinical tools or scientific toys?

Science.gov (United States)

van Mastrigt, E; de Jongste, J C; Pijnenburg, M W

2015-07-01

Current monitoring strategies for respiratory diseases are mainly based on clinical features, lung function and imaging. As airway inflammation is the hallmark of many respiratory diseases in childhood, noninvasive methods to assess the presence and severity of airway inflammation might be helpful in both diagnosing and monitoring paediatric respiratory diseases. At present, the measurement of fractional exhaled nitric oxide is the only noninvasive method available to assess eosinophilic airway inflammation in clinical practice. We aimed to evaluate whether the analysis of volatile organic compounds (VOCs) in exhaled breath (EB) and biomarkers in exhaled breath condensate (EBC) is helpful in diagnosing and monitoring respiratory diseases in children. An extensive literature search was conducted in Medline, Embase and PubMed on the analysis and applications of VOCs in EB and EBC in children. We retrieved 1165 papers, of which nine contained original data on VOCs in EB and 84 on biomarkers in EBC. These were included in this review. We give an overview of the clinical applications in childhood and summarize the methodological issues. Several VOCs in EB and biomarkers in EBC have the potential to distinguish patients from healthy controls and to monitor treatment responses. Lack of standardization of collection methods and analysis techniques hampers the introduction in clinical practice. The measurement of metabolomic profiles may have important advantages over detecting single markers. There is a lack of longitudinal studies and external validation to reveal whether EB and EBC analysis have added value in the diagnostic process and follow-up of children with respiratory diseases. In conclusion, the use of VOCs in EB and biomarkers in EBC as markers of inflammatory airway diseases in children is still a research tool and not validated for clinical use. © 2014 John Wiley & Sons Ltd.

Determining urea levels in exhaled breath condensate with minimal preparation steps and classic LC-MS.

Science.gov (United States)

Pitiranggon, Masha; Perzanowski, Matthew S; Kinney, Patrick L; Xu, Dongqun; Chillrud, Steven N; Yan, Beizhan

2014-10-01

Exhaled breath condensate (EBC) provides a relatively easy, non-invasive method for measuring biomarkers of inflammation and oxidative stress in the airways. However, the levels of these biomarkers in EBC are influenced, not only by their levels in lung lining fluid but also by the volume of water vapor that also condenses during EBC collection. For this reason, the use of a biomarker of dilution has been recommended. Urea has been proposed and utilized as a promising dilution biomarker due to its even distribution throughout the body and relatively low volatility. Current EBC urea analytical methods either are not sensitive enough, necessitating large volumes of EBC, or are labor intensive, requiring a derivatization step or other pretreatment. We report here a straightforward and reliable LC-MS approach that we developed that does not require derivatization or large sample volume (∼36 µL). An Acclaim mixed-mode hydrophilic interaction chromatography column was selected because it can produce good peak symmetry and efficiently separate urea from other polar and nonpolar compounds. To achieve a high recovery rate, a slow and incomplete evaporation method was used followed by a solvent-phase exchange. Among EBC samples collected from 28 children, urea levels were found to be highly variable, with a relative standard deviation of 234%, suggesting high variability in dilution of the lung lining fluid component of EBC. The limit of detection was found to be 0.036 µg/mL. Published by Oxford University Press [2013]. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Manganese in exhaled breath condensate: a new marker of exposure to welding fumes.

Science.gov (United States)

Hulo, Sébastien; Chérot-Kornobis, Nathalie; Howsam, Mike; Crucq, Sébastien; de Broucker, Virginie; Sobaszek, Annie; Edme, Jean-Louis

2014-04-07

To evaluate manganese in exhaled breath condensate (Mn-EBC) as an indicator of exposure to fumes from metal inert gas welding process. We collected EBC and urine from 17 welders and 16 unexposed control subjects after 5 days exposure. Concentrations of manganese (Mn), nickel (Ni), iron (Fe) and chromium (Cr) were measured in EBC and urine samples and correlated with cumulative exposure indices for the working week (CIW) and for the total welding years (WY), based on duration of welding activity and atmospheric metal measurements. Concentrations of Mn and Ni in EBC were significantly higher among welders than controls whereas this difference was not significant for Mn in urine. Levels of Mn and Ni in EBC were not correlated with their respective levels in urine. The linear regressions found significant positive coefficients between Mn-EBC, Ni-EBC, Ni-U and Cr-U concentrations and the cumulative exposure indices. Taking into account tobacco use, statistical analysis showed the same trends except for the relationship between Mn-U and CIW. This pilot study showed that Mn-EBC, as well as Ni-EBC, can serve as reliable indices of occupational exposure to welding fumes and provide complimentary toxicokinetic information to that provided by urine analyses. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Dew inspired breathing-based detection of genetic point mutation visualized by naked eye

Science.gov (United States)

Xie, Liping; Wang, Tongzhou; Huang, Tianqi; Hou, Wei; Huang, Guoliang; Du, Yanan

2014-09-01

A novel label-free method based on breathing-induced vapor condensation was developed for detection of genetic point mutation. The dew-inspired detection was realized by integration of target-induced DNA ligation with rolling circle amplification (RCA). The vapor condensation induced by breathing transduced the RCA-amplified variances in DNA contents into visible contrast. The image could be recorded by a cell phone for further or even remote analysis. This green assay offers a naked-eye-reading method potentially applied for point-of-care liver cancer diagnosis in resource-limited regions.

Localized nonlinear waves and dynamical stability in spinor Bose–Einstein condensates with time–space modulation

Science.gov (United States)

Yao, Yu-Qin; Han, Wei; Li, Ji; Liu, Wu-Ming

2018-05-01

Nonlinearity is one of the most remarkable characteristics of Bose–Einstein condensates (BECs). Much work has been done on one- and two-component BECs with time- or space-modulated nonlinearities, while there is little work on spinor BECs with space–time-modulated nonlinearities. In the present paper we investigate localized nonlinear waves and dynamical stability in spinor Bose–Einstein condensates with nonlinearities dependent on time and space. We solve the three coupled Gross–Pitaevskii equations by similarity transformation and obtain two families of exact matter wave solutions in terms of Jacobi elliptic functions and the Mathieu equation. The localized states of the spinor matter wave describe the dynamics of vector breathing solitons, moving breathing solitons, quasi-breathing solitons and resonant solitons. The results show that one-order vector breathing solitons, quasi-breathing solitons, resonant solitons and the moving breathing solitons ψ ±1 are all stable, but the moving breathing soliton ψ 0 is unstable. We also present the experimental parameters to realize these phenomena in future experiments.

Comparative analysis of selected exhaled breath biomarkers obtained with two different temperature-controlled devices

Directory of Open Access Journals (Sweden)

Brüning Thomas

2009-11-01

Full Text Available Abstract Background The collection of exhaled breath condensate (EBC is a suitable and non-invasive method for evaluation of airway inflammation. Several studies indicate that the composition of the condensate and the recovery of biomarkers are affected by physical characteristics of the condensing device and collecting circumstances. Additionally, there is an apparent influence of the condensing temperature, and often the level of detection of the assay is a limiting factor. The ECoScreen2 device is a new, partly single-use disposable system designed for studying different lung compartments. Methods EBC samples were collected from 16 healthy non-smokers by using the two commercially available devices ECoScreen2 and ECoScreen at a controlled temperature of -20°C. EBC volume, pH, NOx, LTB4, PGE2, 8-isoprostane and cys-LTs were determined. Results EBC collected with ECoScreen2 was less acidic compared to ECoScreen. ECoScreen2 was superior concerning condensate volume and detection of biomarkers, as more samples were above the detection limit (LTB4 and PGE2 or showed higher concentrations (8-isoprostane. However, NOx was detected only in EBC sampled by ECoScreen. Conclusion ECoScreen2 in combination with mediator specific enzyme immunoassays may be suitable for measurement of different biomarkers. Using this equipment, patterns of markers can be assessed that are likely to reflect the complex pathophysiological processes in inflammatory respiratory disease.

Analysis of aldehydes in human exhaled breath condensates by in-tube SPME-HPLC.

Science.gov (United States)

Wang, ShuLing; Hu, Sheng; Xu, Hui

2015-11-05

In this paper, polypyrrole/graphene (PPy/G) composite coating was prepared by a facile electrochemical polymerization strategy on the inner surface of a stainless steel (SS) tube. Based on the coating tube, a novel online in-tube solid-phase microextraction -high performance liquid chromatography (IT-SPME-HPLC) was developed and applied for the extraction of aldehydes in the human exhaled breath condensates (EBC). The hybrid PPy/G nanocomposite exhibits remarkable chemical and mechanical stability, high selectivity, and satisfactory extraction performance toward aldehyde compounds. Moreover, the proposed online IT-SPME-HPLC method possesses numerous superiorities, such as time and cost saving, process simplicity, high precision and sensitivity. Some parameters related to extraction efficiency were optimized systematically. Under the optimal conditions, the recoveries of the aldehyde compounds at three spiked concentration levels varied in the range of 85%-117%. Good linearity was obtained with excellent correlation coefficients (R(2)) being larger than 0.994. The relative standard deviations (n = 5) of the method ranged from 1.8% to 11.3% and the limits of detection were between 2.3 and 3.3 nmol L(-1). The successful application of the proposed method in human EBC indicated that it is a promising approach for the determination of trace aldehyde metabolites in complex EBC samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of Ambient and Atmospheric Pressure Ion Sources for Cystic Fibrosis Exhaled Breath Condensate Ion Mobility-Mass Spectrometry Metabolomics

Science.gov (United States)

Zang, Xiaoling; Pérez, José J.; Jones, Christina M.; Monge, María Eugenia; McCarty, Nael A.; Stecenko, Arlene A.; Fernández, Facundo M.

2017-08-01

Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the gene that encodes the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The vast majority of the mortality is due to progressive lung disease. Targeted and untargeted CF breath metabolomics investigations via exhaled breath condensate (EBC) analyses have the potential to expose metabolic alterations associated with CF pathology and aid in assessing the effectiveness of CF therapies. Here, transmission-mode direct analysis in real time traveling wave ion mobility spectrometry time-of-flight mass spectrometry (TM-DART-TWIMS-TOF MS) was tested as a high-throughput alternative to conventional direct infusion (DI) electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) methods, and a critical comparison of the three ionization methods was conducted. EBC was chosen as the noninvasive surrogate for airway sampling over expectorated sputum as EBC can be collected in all CF subjects regardless of age and lung disease severity. When using pooled EBC collected from a healthy control, ESI detected the most metabolites, APCI a log order less, and TM-DART the least. TM-DART-TWIMS-TOF MS was used to profile metabolites in EBC samples from five healthy controls and four CF patients, finding that a panel of three discriminant EBC metabolites, some of which had been previously detected by other methods, differentiated these two classes with excellent cross-validated accuracy.

Exhaled breath condensate cysteinyl leukotrienes and airway remodeling in childhood asthma: a pilot study

Directory of Open Access Journals (Sweden)

Kharitonov Sergei A

2006-04-01

Full Text Available Abstract Background It has been suggested that cysteinyl leukotrienes (cysLTs play an important role in airway remodeling. Previous reports have indicated that cysLTs augment human airway smooth muscle cell proliferation. Recently, cysLTs have been measured in exhaled breath condensate (EBC. The aim of this study was to evaluate the relationship between cysLTs in EBC and another marker of airway remodeling, reticular basement membrane (RBM thickening, in endobronchial biopsies in children. Methods 29 children, aged 4–15 years, with moderate to severe persistent asthma, who underwent bronchoscopy as part of their clinical assessment, were included. Subjects underwent spirometry and EBC collection for cysLTs analysis, followed by bronchoscopy and endobronchial biopsy within 24 hours. Results EBC cysLTs were significantly lower in asthmatic children who were treated with montelukast than in those who were not (median (interquartile range 36.62 (22.60–101.05 versus 249.1 (74.21–526.36 pg/ml, p = 0.004. There was a significant relationship between EBC cysLTs and RBM thickness in the subgroup of children who were not treated with montelukast (n = 13, r = 0.75, p = 0.003. Conclusion EBC cysLTs appear to be associated with RBM thickening in asthma.

Study of exhaled breath condensate sample preparation for metabolomics analysis by LC-MS/MS in high resolution mode.

Science.gov (United States)

Fernández-Peralbo, M A; Calderón Santiago, M; Priego-Capote, F; Luque de Castro, M D

2015-11-01

Metabolomic analysis of exhaled breath condensate (EBC) requires an unavoidable sample preparation step because of the low concentration of its components, and potential cleanup for possible interferents. Sample preparation based on protein precipitation (PP), solid-phase extraction (SPE) by hydrophilic and lipophilic sorbents or lyophilization has demonstrated that the analytical sample from the last is largely the best because lyophilization allows reconstitution in a volume as small as required (preconcentration factors up to 80-times with respect to the original sample), thus doubling the number of detected compounds as compared with the other alternatives (47 versus 25). In addition, PP and/or SPE cleanup are unnecessary as no effect from the EBC components removed by these steps appears in the chromatograms. The total 49 EBC compounds tentatively identified and confirmed by MS/MS in this research include amino acids, fatty acids, fatty amides, fatty aldehydes, sphingoid bases, oxoanionic compounds, imidazoles, hydroxy acids and aliphatic acyclic acids. Copyright © 2015 Elsevier B.V. All rights reserved.

The diagnostic value of gastroesophageal reflux disease (GERD) symptoms and detection of pepsin and bile acids in bronchoalveolar lavage fluid and exhaled breath condensate for identifying lung transplantation patients with GERD-induced aspiration.

Science.gov (United States)

Reder, Nicholas P; Davis, Christopher S; Kovacs, Elizabeth J; Fisichella, P Marco

2014-06-01

Gastroesophageal reflux disease (GERD) is thought to lead to aspiration and bronchiolitis obliterans syndrome after lung transplantation. Unfortunately, the identification of patients with GERD who aspirate still lacks clear diagnostic indicators. The authors hypothesized that symptoms of GERD and detection of pepsin and bile acids in the bronchoalveolar lavage fluid (BAL) and exhaled breath condensate (EBC) are effective for identifying lung transplantation patients with GERD-induced aspiration. From November 2009 to November 2010, 85 lung transplantation patients undergoing surveillance bronchoscopy were prospectively enrolled. For these patients, self-reported symptoms of GERD were correlated with levels of pepsin and bile acids in BAL and EBC and with GERD status assessed by 24-h pH monitoring. The sensitivity and specificity of pepsin and bile acids in BAL and EBC also were compared with the presence of GERD in 24-h pH monitoring. The typical symptoms of GERD (heartburn and regurgitation) had modest sensitivity and specificity for detecting GERD and aspiration. The atypical symptoms of GERD (aspiration and bronchitis) showed better identification of aspiration as measured by detection of pepsin and bile acids in BAL. The sensitivity and specificity of pepsin in BAL compared with GERD by 24-h pH monitoring were respectively 60 and 45 %, whereas the sensitivity and specificity of bile acids in BAL were 67 and 80 %. These data indicate that the measurement of pepsin and bile acids in BAL can provide additional data for identifying lung transplantation patients at risk for GERD-induced aspiration compared with symptoms or 24-h pH monitoring alone. These results support a diagnostic role for detecting markers of aspiration in BAL, but this must be validated in larger studies.

Noninvasive Ph-telemetric Measurement of Gastrointestinal Function

Science.gov (United States)

Tietze, Karen J.

1991-01-01

The purpose of this study was to gain experience with and validate the Heidelberg pH-telemetric methodology in order to determine if the pH-telemetric methodology would be a useful noninvasive measure of gastrointestinal transit time for future ground-based and in-flight drug evaluation studies. The Heidelberg pH metering system is a noninvasive, nonradioactive telemetric system that, following oral ingestion, continuously measures intraluminal pH of the stomach, duodenum, small bowel, ileocecal junction, and large bowel. Gastrointestinal motility profiles were obtained in normal volunteers using the lactulose breath-hydrogen and Heidelberg pH metering techniques. All profiles were obtained in the morning after an overnight fast. Heidelberg pH profiles were obtained in the fasting and fed states; lactulose breath-hydrogen profiles were obtained after a standard breakfast. Mouth-to-cecum transit time was measured as the interval from administration of lactulose (30 ml; 20 g) to a sustained increase in breath-hydrogen of 10 ppm or more. Gastric emptying time was measured as the interval from the administration of the Heidelberg capsule to a sustained increase in pH of three units or more.

Breathing, feeding, and neuroprotection

National Research Council Canada - National Science Library

Homma, Ikuo; Shioda, S

2006-01-01

... of knowledge of brain functions and morphology. Akiyoshi Hosoyamada, M.D., Ph.D. President Showa University, Tokyo 142-8555, Japan December 2005Preface Brain research is on the march, with several advanced technical developments and new findings uncovered almost daily. Within the brain-research fields, we focus on breathing, neuroprotection, an...

Evaluation of oxidative stress using exhaled breath 8-isoprostane ...

African Journals Online (AJOL)

Background: There have been limited numbers of studies on patients with chronic kidney disease (CKD) to determine oxidative stress in exhaled breath condensate (EBC). Those two studies have been carried out on hemodialysis patients, and hydrogen peroxide and nitric oxide have been studied in order to show ...

News from the Breath Analysis Summit 2011.

Science.gov (United States)

Corradi, Massimo; Mutti, Antonio

2012-06-01

This special section highlights some of the important work presented at the Breath Analysis Summit 2011, which was held in Parma (Italy) from 11 to 14 September 2011. The meeting, which was jointly organized by the International Association for Breath Research and the University of Parma, was attended by more than 250 delegates from 33 countries, and offered 34 invited lectures and 64 unsolicited scientific contributions. The summit was organized to provide a forum to scientists, engineers and clinicians to present their latest findings and to meet industry executives and entrepreneurs to discuss key trends, future directions and technologies available for breath analysis. A major focus was on nitric oxide, exhaled breath condensate, electronic nose, mass spectrometry and newer sensor technologies. Medical applications ranged from asthma and other respiratory diseases to gastrointestinal disease, occupational diseases, critical care and cancer. Most people identify breath tests with breathalysers used by police to estimate ethanol concentration in blood. However, breath testing has far more sophisticated applications. Breath analysis is rapidly evolving as a new frontier in medical testing for disease states in the lung and beyond. Every individual has a breath fingerprint-or 'breathprint'-that can provide useful information about his or her state of health. This breathprint comprises the many thousands of molecules that are expelled with each breath we exhale. Breath research in the past few years has uncovered the scientific and molecular basis for such clinical observations. Relying on mass spectrometry, we have been able to identify many such unique substances in exhaled breath, including gases, such as nitric oxide (NO) and carbon monoxide (CO), and a wide array of volatile organic compounds. Exhaled breath also carries aerosolized droplets that can be collected as an exhaled breath condensate that contains endogenously produced non-volatile compounds. Breath

Acid-base regulation in intensively farmed air-breathing fish

DEFF Research Database (Denmark)

Bayley, Mark; Damsgaard, Christian; Thomsen, Mikkel

Hypercapnia in slow moving organically loaded tropical waters is a natural occurrence with several records of pCO2 at 60 mm Hg. Despite this, studies on South American air-breathing fish have revealed a low capacity for extracellular pH (pHe) regulation. The two underlying reasons proposed are; 1......) an osmorespiratory compromise with reduced branchial surface area and reduced branchial ventilation 2) low ion concentrations in the very soft amazon waters limiting the capacity for branchial pH regulation. The Mekong delta region houses extremely intensive aquaculture of a large number of air-breathing species...

Toward a hydrogen peroxide sensor for exhaled breath analysis

NARCIS (Netherlands)

Wiedemair, Justyna; van Dorp, Henriëtte; Olthuis, Wouter; van den Berg, Albert

2011-01-01

In this contribution a chip-integrated amperometric sensor for the detection of H2O2 in exhaled breath condensate (EBC) is reported. The electrode chip is characterized, and detection of H2O2 in an aqueous phase is shown by means of cyclic voltammetry (CV) and amperometry. Variation of conditions

Determination of hexavalent chromium in exhaled breath condensate and environmental air among chrome plating workers.

Science.gov (United States)

Goldoni, Matteo; Caglieri, Andrea; Poli, Diana; Vettori, Maria Vittoria; Corradi, Massimo; Apostoli, Pietro; Mutti, Antonio

2006-03-15

Chromium speciation has attracted attention because of the different toxicity of Cr(III), which is considered relatively non-toxic, and Cr(VI), which can cross cell membranes mainly as a chromate anion and has been classified as a class I human carcinogen. The aims of the present study were to measure soluble Cr(VI) levels in environmental samples, to develop a simple method of quantifying Cr(VI) in exhaled breath condensate (EBC), and to follow the kinetics of EBC Cr(VI) in chrome plating workers.Personal air samples were collected from 10 chrome platers; EBC was collected from the same workers immediately after the work shift on Tuesday and before the work shift on the following Wednesday. Environmental and EBC Cr(VI) levels were determined by means of colorimetry and electrothermal absorption atomic spectrometry, respectively.The method of detecting Cr(VI) in environmental air was based on the extraction of the Cr(VI)-diphenylcarbazide (Cr(VI)-DPC) complex in 1-butanol, whereas EBC Cr(VI) was determined using a solvent extraction of Cr(VI) as an ion pair with tetrabutylammonium ion, and subsequent direct determination of the complex (Cr(VI)-DPC) in EBC.Kinetic data showed that airborne Cr(VI) was reduced by 50% in airway lining fluid sampled at the end of exposure and that there was a further 50% reduction after about 15 h. The persistence of Cr(VI) in EBC supports the use of EBC in assessing target tissue levels of Cr(VI).

Determination of hexavalent chromium in exhaled breath condensate and environmental air among chrome plating workers

International Nuclear Information System (INIS)

Goldoni, Matteo; Caglieri, Andrea; Poli, Diana; Vettori, Maria Vittoria; Corradi, Massimo; Apostoli, Pietro; Mutti, Antonio

2006-01-01

Chromium speciation has attracted attention because of the different toxicity of Cr(III), which is considered relatively non-toxic, and Cr(VI), which can cross cell membranes mainly as a chromate anion and has been classified as a class I human carcinogen. The aims of the present study were to measure soluble Cr(VI) levels in environmental samples, to develop a simple method of quantifying Cr(VI) in exhaled breath condensate (EBC), and to follow the kinetics of EBC Cr(VI) in chrome plating workers. Personal air samples were collected from 10 chrome platers; EBC was collected from the same workers immediately after the work shift on Tuesday and before the work shift on the following Wednesday. Environmental and EBC Cr(VI) levels were determined by means of colorimetry and electrothermal absorption atomic spectrometry, respectively. The method of detecting Cr(VI) in environmental air was based on the extraction of the Cr(VI)-diphenylcarbazide (Cr(VI)-DPC) complex in 1-butanol, whereas EBC Cr(VI) was determined using a solvent extraction of Cr(VI) as an ion pair with tetrabutylammonium ion, and subsequent direct determination of the complex (Cr(VI)-DPC) in EBC. Kinetic data showed that airborne Cr(VI) was reduced by 50% in airway lining fluid sampled at the end of exposure and that there was a further 50% reduction after about 15 h. The persistence of Cr(VI) in EBC supports the use of EBC in assessing target tissue levels of Cr(VI)

Determination of hexavalent chromium in exhaled breath condensate and environmental air among chrome plating workers

Energy Technology Data Exchange (ETDEWEB)

Goldoni, Matteo [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); National Institute of Occupational Safety and Prevention, Research Centre at University of Parma, Parma (Italy); Caglieri, Andrea [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); Poli, Diana [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); National Institute of Occupational Safety and Prevention, Research Centre at University of Parma, Parma (Italy); Vettori, Maria Vittoria [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); National Institute of Occupational Safety and Prevention, Research Centre at University of Parma, Parma (Italy); Corradi, Massimo [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); National Institute of Occupational Safety and Prevention, Research Centre at University of Parma, Parma (Italy); Apostoli, Pietro [Laboratory of Industrial Hygiene, Department of Experimental and Applied Medicine, University of Brescia (Italy); Mutti, Antonio [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy)]. E-mail: antonio.mutti@unipr.it

2006-03-15

Chromium speciation has attracted attention because of the different toxicity of Cr(III), which is considered relatively non-toxic, and Cr(VI), which can cross cell membranes mainly as a chromate anion and has been classified as a class I human carcinogen. The aims of the present study were to measure soluble Cr(VI) levels in environmental samples, to develop a simple method of quantifying Cr(VI) in exhaled breath condensate (EBC), and to follow the kinetics of EBC Cr(VI) in chrome plating workers. Personal air samples were collected from 10 chrome platers; EBC was collected from the same workers immediately after the work shift on Tuesday and before the work shift on the following Wednesday. Environmental and EBC Cr(VI) levels were determined by means of colorimetry and electrothermal absorption atomic spectrometry, respectively. The method of detecting Cr(VI) in environmental air was based on the extraction of the Cr(VI)-diphenylcarbazide (Cr(VI)-DPC) complex in 1-butanol, whereas EBC Cr(VI) was determined using a solvent extraction of Cr(VI) as an ion pair with tetrabutylammonium ion, and subsequent direct determination of the complex (Cr(VI)-DPC) in EBC. Kinetic data showed that airborne Cr(VI) was reduced by 50% in airway lining fluid sampled at the end of exposure and that there was a further 50% reduction after about 15 h. The persistence of Cr(VI) in EBC supports the use of EBC in assessing target tissue levels of Cr(VI)

Exhaled Breath Condensate Detects Baseline Reductions in Chloride and Increases in Response to Albuterol in Cystic Fibrosis Patients

Directory of Open Access Journals (Sweden)

Courtney M. Wheatley

2013-01-01

Full Text Available Impaired ion regulation and dehydration is the primary pathophysiology in cystic fibrosis (CF lung disease. A potential application of exhaled breath condensate (EBC collection is to assess airway surface liquid ionic composition at baseline and in response to pharmacological therapy in CF. Our aims were to determine if EBC could detect differences in ion regulation between CF and healthy and measure the effect of the albuterol on EBC ions in these populations. Baseline EBC Cl − , DLCO and SpO 2 were lower in CF (n = 16 compared to healthy participants (n = 16. EBC Cl − increased in CF subjects, while there was no change in DLCO or membrane conductance, but a decrease in pulmonary-capillary blood volume in both groups following albuterol. This resulted in an improvement in diffusion at the alveolar-capillary unit, and removal of the baseline difference in SpO 2 by 90-minutes in CF subjects. These results demonstrate that EBC detects differences in ion regulation between healthy and CF individuals, and that albuterol mediates increases in Cl − in CF, suggesting that the benefits of albuterol extend beyond simple bronchodilation.

Moderate altitude but not additional endurance training increases markers of oxidative stress in exhaled breath condensate.

Science.gov (United States)

Heinicke, Ilmar; Boehler, Annette; Rechsteiner, Thomas; Bogdanova, Anna; Jelkmann, Wolfgang; Hofer, Markus; Rawlings, Pablo; Araneda, Oscar F; Behn, Claus; Gassmann, Max; Heinicke, Katja

2009-07-01

Oxidative stress occurs at altitude, and physical exertion might enhance this stress. In the present study, we investigated the combined effects of exercise and moderate altitude on redox balance in ten endurance exercising biathletes, and five sedentary volunteers during a 6-week-stay at 2,800 m. As a marker for oxidative stress, hydrogen peroxide (H(2)O(2)) was analyzed by the biosensor measuring system Ecocheck, and 8-iso prostaglandin F2alpha (8-iso PGF2alpha) was determined by enzyme immunoassay in exhaled breath condensate (EBC). To determine the whole blood antioxidative capacity, we measured reduced glutathione (GSH) enzymatically using Ellman's reagent. Exercising athletes and sedentary volunteers showed increased levels of oxidative markers at moderate altitude, contrary to our expectations; there was no difference between both groups. Therefore, all subjects' data were pooled to examine the oxidative stress response exclusively due to altitude exposure. H(2)O(2) levels increased at altitude and remained elevated for 3 days after returning to sea level (p altitude, but declined immediately after returning to sea level (p altitude resulted in elevated GSH levels (p altitude (p altitude for up to 6 weeks increases markers of oxidative stress in EBC independent of additional endurance training. Notably, this oxidative stress is still detectable 3 days upon return to sea level.

Specific Metabolome Profile of Exhaled Breath Condensate in Patients with Shock and Respiratory Failure: A Pilot Study

Directory of Open Access Journals (Sweden)

Brice Fermier

2016-09-01

Full Text Available Background: Shock includes different pathophysiological mechanisms not fully understood and remains a challenge to manage. Exhaled breath condensate (EBC may contain relevant biomarkers that could help us make an early diagnosis or better understand the metabolic perturbations resulting from this pathological situation. Objective: we aimed to establish the metabolomics signature of EBC from patients in shock with acute respiratory failure in a pilot study. Material and methods: We explored the metabolic signature of EBC in 12 patients with shock compared to 14 controls using LC-HRMS. We used a non-targeted approach, and we performed a multivariate analysis based on Orthogonal Partial Least Square-Discriminant Analysis (OPLS-DA to differentiate between the two groups of patients. Results: We optimized the procedure of EBC collection and LC-HRMS detected more than 1000 ions in this fluid. The optimization of multivariate models led to an excellent model of differentiation for both groups (Q2 > 0.4 after inclusion of only 6 ions. Discussion and conclusion: We validated the procedure of EBC collection and we showed that the metabolome profile of EBC may be relevant in characterizing patients with shock. We performed well in distinguishing these patients from controls, and the identification of relevant compounds may be promising for ICC patients.

Measurement of tumor necrosis factor-α, leukotriene B4, and interleukin 8 in the exhaled breath condensate in patients with acute exacerbations of chronic obstructive pulmonary disease

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Fanny WS Ko

2008-12-01

Full Text Available Fanny WS Ko1, Ting-Fan Leung2, Gary WK Wong2, Jenny Ngai1, Kin W To1, Susanna Ng1, David SC Hui11Department of Medicine and Therapeutics; 2Department of Pediatrics, The Chinese University of Hong Kong, Hong KongBackground: Assessment of airway inflammation in the clinical course of acute exacerbations of chronic obstructive pulmonary disease (AECOPD may advance our understanding of the pathogenesis and treatment.Objectives: To assess airway inflammation in patients during the course of AECOPD by serial analyses of their exhaled breath condensates (EBC.Methods: Twenty-six patients with AECOPD (22 males, mean[SD] percentage predicted forced expiratory volume in one second (FEV1 44.8 [14.3], 11 with stable COPD, and 14 age and sex-matched healthy controls were studied. Patients with AECOPD were treated with systemic steroid and antibiotic for 7 days. EBC was collected from each patient with AECOPD on Day 5, 14, 30, and 60 post-hospitalization using EcoScreen (VIASYS Healthcare, USA during tidal breathing over 10 minutes. Concentrations of tumor necrosis factor-α (TNF-α, leukotriene B4 (LTB4, and interleukin-8 (IL-8 were measured by enzyme-linked immunosorbent assay.Results: The median (IQR of TNF-α level on Day 5 was 5.08 (3.80–6 .32 pg/ml, which was lower than on Day 14 (5.84 [4.91–9.14] pg/ml, p = 0.017, Day 30 (6.14 [3.82–7.67] pg/ml, p = 0.045, and Day 60 (5.60 [4.53–8.80] pg/ml, p = 0.009. On Day 60, subjects receiving inhaled corticosteroid (ICS had a lower level of TNF-α than those who were not (4.82 [4.06–5.65] vs 7.66 [5.48–10.9] pg/ml, p = 0.02. EBC LTB4 level did not change significantly during recovery from AECOPD whereas IL-8 was mostly undetectable.Conclusions: EBC TNF-α level was low in patients receiving systemic steroid and antibiotic therapy for AECOPD. These findings suggest a potential role for serial EBC TNF-α for noninvasive monitoring of disease activity.Keywords: COPD, exacerbation, exhaled breath

Response of Hepatoma 9618a and Normal Liver to Host Carbogen and Carbon Monoxide Breathing

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Simon P. Robinson

1999-12-01

Full Text Available The effects of hyperoxia (induced by host carbogen 95% oxygen/5% carbon dioxide breathing. and hypoxia (induced by host carbon monoxide CO at 660 ppm. breathing were compared by using noninvasive magnetic resonance (MR methods to gain simultaneous information on blood flow/oxygenation and the bioenergetic status of rat Morris H9618a hepatomas. Both carbogen and CO breathing induced a 1.5- to 2-fold increase in signal intensity in blood oxygenation level dependent (BOLD MR images. This was due to a decrease in deoxyhemoglobin (deoxyHb, which acts as an endogenous contrast agent, caused either by formation of oxyhemoglobin in the case of carbogen breathing, or carboxyhemoglobin with CO breathing. The results were confirmed by observation of similar changes in deoxyHb in arterial blood samples examined ex vivo after carbogen or CO breathing. There was no change in nucleoside triphosphates (NTP/PI in either tumor or liver after CO breathing, whereas NTP/Pl increased twofold in the hepatoma (but not in the liver after carbogen breathing. No changes in tumor intracellular pH were seen after either treatment, whereas extracellular pH became more alkaline after CO breathing and more acid after carbogen breathing, respectively. This tumor type and the liver are unaffected by CO breathing at 660 ppm, which implies an adequate oxygen supply.

Biomarkers of exposure to stainless steel tungsten inert gas welding fumes and the effect of exposure on exhaled breath condensate.

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Riccelli, Maria Grazia; Goldoni, Matteo; Andreoli, Roberta; Mozzoni, Paola; Pinelli, Silvana; Alinovi, Rossella; Selis, Luisella; Mutti, Antonio; Corradi, Massimo

2018-08-01

The respiratory tract is the main target organ of the inhaled hexavalent chromium (Cr-VI) and nickel (Ni) contained in stainless steel (SS) welding fumes (WFs). The aim of this study was to investigate the Cr and Ni content of the exhaled breath condensate (EBC) of SS tungsten inert gas (TIG) welders, and relate their concentrations with oxidative stress and inflammatory biomarkers. EBC and urine from 100 SS TIG welders were collected pre-(T 0 ) and post-shift (T 1 ) on a Friday, and pre-shift (T 2 ) on the following Monday morning. Both EBC and urinary Cr concentrations were higher at T 1 (0.08 μg/L and 0.71 μg/g creatinine) and T 0 (0.06 μg/L and 0.74 μg/g creatinine) than at T 2 (below the limit of detection [LOD] and 0.59 μg/g creatinine), and EBC Ni concentrations generally remained welding also play a role in generating lung oxidative stress. Copyright © 2018 Elsevier B.V. All rights reserved.

Assessing the efficacy of immunotherapy with a glutaraldehyde-modified house dust mite extract in children by monitoring changes in clinical parameters and inflammatory markers in exhaled breath.

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Lozano, Jaime; Cruz, María-Jesús; Piquer, Mónica; Giner, Maria-Teresa; Plaza, Ana María

2014-01-01

The aim of this study was to evaluate the effectiveness of specific immunotherapy (SIT) management with allergoids in children with allergic asthma by monitoring changes in clinical parameters and inflammatory markers in exhaled breath. The study population included 43 patients (24 males) of 6-14 years of age, who had allergic asthma and were sensitized to mites. Twenty-three individuals were treated with subcutaneous SIT (PURETHAL® Mites, HAL Allergy) for 8 months, i.e. the SIT group, and 20 were given medication to treat symptoms only, i.e. the control group. Before treatment and after 4 and 8 months, several clinical parameters, the levels of exhaled nitric oxide and the pH of exhaled breath condensate (EBC) were determined. The SIT group presented with an improvement in asthma classification, a reduction in maintenance drug therapy and improved scores on the quality-of-life questionnaire. These changes were not observed in the control group. Both groups presented significant decreases in EBC pH values at 4 and 8 months after treatment compared to at baseline. However, analysis of the variable 'ratio' showed an increase in the EBC pH values after 8 months of treatment in the SIT group compared with the values at 4 months. SIT with standardized mite extract reduces asthma symptoms in children. A decrease in EBC pH values was observed in both groups, although the SIT group presented a tendency of recovered values after 8 months. Future studies of EBC pH monitoring in the longer term are needed to determine the effectiveness of this marker. © 2014 S. Karger AG, Basel.

High capacity for extracellular acid-base regulation in the air-breathing fish Pangasianodon hypophthalmus.

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Damsgaard, Christian; Gam, Le Thi Hong; Tuong, Dang Diem; Thinh, Phan Vinh; Huong Thanh, Do Thi; Wang, Tobias; Bayley, Mark

2015-05-01

The evolution of accessory air-breathing structures is typically associated with reduction of the gills, although branchial ion transport remains pivotal for acid-base and ion regulation. Therefore, air-breathing fishes are believed to have a low capacity for extracellular pH regulation during a respiratory acidosis. In the present study, we investigated acid-base regulation during hypercapnia in the air-breathing fish Pangasianodon hypophthalmus in normoxic and hypoxic water at 28-30°C. Contrary to previous studies, we show that this air-breathing fish has a pronounced ability to regulate extracellular pH (pHe) during hypercapnia, with complete metabolic compensation of pHe within 72 h of exposure to hypoxic hypercapnia with CO2 levels above 34 mmHg. The high capacity for pHe regulation relies on a pronounced ability to increase levels of HCO3(-) in the plasma. Our study illustrates the diversity in the physiology of air-breathing fishes, such that generalizations across phylogenies may be difficult. © 2015. Published by The Company of Biologists Ltd.

PH adjustment of power plant cooling water with flue gas/fly ash

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Brady, Patrick V.; Krumhansl, James L.

2015-09-22

A system including a vessel including a heat source and a flue; a turbine; a condenser; a fluid conduit circuit disposed between the vessel, the turbine and the condenser; and a diverter coupled to the flue to direct a portion of an exhaust from the flue to contact with a cooling medium for the condenser water. A method including diverting a portion of exhaust from a flue of a vessel; modifying the pH of a cooling medium for a condenser with the portion of exhaust; and condensing heated fluid from the vessel with the pH modified cooling medium.

Analysis of volatile compounds in exhaled breath condensate in patients with severe pulmonary arterial hypertension.

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Mansoor, J K; Schelegle, Edward S; Davis, Cristina E; Walby, William F; Zhao, Weixiang; Aksenov, Alexander A; Pasamontes, Alberto; Figueroa, Jennifer; Allen, Roblee

2014-01-01

An important challenge to pulmonary arterial hypertension (PAH) diagnosis and treatment is early detection of occult pulmonary vascular pathology. Symptoms are frequently confused with other disease entities that lead to inappropriate interventions and allow for progression to advanced states of disease. There is a significant need to develop new markers for early disease detection and management of PAH. Exhaled breath condensate (EBC) samples were compared from 30 age-matched normal healthy individuals and 27 New York Heart Association functional class III and IV idiopathic pulmonary arterial hypertenion (IPAH) patients, a subgroup of PAH. Volatile organic compounds (VOC) in EBC samples were analyzed using gas chromatography/mass spectrometry (GC/MS). Individual peaks in GC profiles were identified in both groups and correlated with pulmonary hemodynamic and clinical endpoints in the IPAH group. Additionally, GC/MS data were analyzed using autoregression followed by partial least squares regression (AR/PLSR) analysis to discriminate between the IPAH and control groups. After correcting for medicaitons, there were 62 unique compounds in the control group, 32 unique compounds in the IPAH group, and 14 in-common compounds between groups. Peak-by-peak analysis of GC profiles of IPAH group EBC samples identified 6 compounds significantly correlated with pulmonary hemodynamic variables important in IPAH diagnosis. AR/PLSR analysis of GC/MS data resulted in a distinct and identifiable metabolic signature for IPAH patients. These findings indicate the utility of EBC VOC analysis to discriminate between severe IPAH and a healthy population; additionally, we identified potential novel biomarkers that correlated with IPAH pulmonary hemodynamic variables that may be important in screening for less severe forms IPAH.

Analysis of volatile compounds in exhaled breath condensate in patients with severe pulmonary arterial hypertension.

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J K Mansoor

Full Text Available BACKGROUND: An important challenge to pulmonary arterial hypertension (PAH diagnosis and treatment is early detection of occult pulmonary vascular pathology. Symptoms are frequently confused with other disease entities that lead to inappropriate interventions and allow for progression to advanced states of disease. There is a significant need to develop new markers for early disease detection and management of PAH. METHODOLGY AND FINDINGS: Exhaled breath condensate (EBC samples were compared from 30 age-matched normal healthy individuals and 27 New York Heart Association functional class III and IV idiopathic pulmonary arterial hypertenion (IPAH patients, a subgroup of PAH. Volatile organic compounds (VOC in EBC samples were analyzed using gas chromatography/mass spectrometry (GC/MS. Individual peaks in GC profiles were identified in both groups and correlated with pulmonary hemodynamic and clinical endpoints in the IPAH group. Additionally, GC/MS data were analyzed using autoregression followed by partial least squares regression (AR/PLSR analysis to discriminate between the IPAH and control groups. After correcting for medicaitons, there were 62 unique compounds in the control group, 32 unique compounds in the IPAH group, and 14 in-common compounds between groups. Peak-by-peak analysis of GC profiles of IPAH group EBC samples identified 6 compounds significantly correlated with pulmonary hemodynamic variables important in IPAH diagnosis. AR/PLSR analysis of GC/MS data resulted in a distinct and identifiable metabolic signature for IPAH patients. CONCLUSIONS: These findings indicate the utility of EBC VOC analysis to discriminate between severe IPAH and a healthy population; additionally, we identified potential novel biomarkers that correlated with IPAH pulmonary hemodynamic variables that may be important in screening for less severe forms IPAH.

Aspirin provocation increases 8-iso-PGE2 in exhaled breath condensate of aspirin-hypersensitive asthmatics.

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Mastalerz, Lucyna; Januszek, Rafał; Kaszuba, Marek; Wójcik, Krzysztof; Celejewska-Wójcik, Natalia; Gielicz, Anna; Plutecka, Hanna; Oleś, Krzysztof; Stręk, Paweł; Sanak, Marek

2015-09-01

Isoprostanes are bioactive compounds formed by non-enzymatic oxidation of polyunsaturated fatty acids, mostly arachidonic, and markers of free radical generation during inflammation. In aspirin exacerbated respiratory disease (AERD), asthmatic symptoms are precipitated by ingestion of non-steroid anti-inflammatory drugs capable for pharmacologic inhibition of cyclooxygenase-1 isoenzyme. We investigated whether aspirin-provoked bronchoconstriction is accompanied by changes of isoprostanes in exhaled breath condensate (EBC). EBC was collected from 28 AERD subjects and 25 aspirin-tolerant asthmatics before and after inhalatory aspirin challenge. Concentrations of 8-iso-PGF2α, 8-iso-PGE2, and prostaglandin E2 were measured using gas chromatography/mass spectrometry. Leukotriene E4 was measured by immunoassay in urine samples collected before and after the challenge. Before the challenge, exhaled 8-iso-PGF2α, 8-iso-PGE2, and PGE2 levels did not differ between the study groups. 8-iso-PGE2 level increased in AERD group only (p=0.014) as a result of the aspirin challenge. Urinary LTE4 was elevated in AERD, both in baseline and post-challenge samples. Post-challenge airways 8-iso-PGE2 correlated positively with urinary LTE4 level (p=0.046), whereas it correlated negatively with the provocative dose of aspirin (p=0.027). A significant increase of exhaled 8-iso-PGE2 after inhalatory challenge with aspirin was selective and not present for the other isoprostane measured. This is a novel finding in AERD, suggesting that inhibition of cyclooxygenase may elicit 8-iso-PGE2 production in a specific mechanism, contributing to bronchoconstriction and systemic overproduction of cysteinyl leukotrienes. Copyright © 2015 Elsevier Inc. All rights reserved.

Association of Lung Inflammatory Cells with Small Airways Function and Exhaled Breath Markers in Smokers - Is There a Specific Role for Mast Cells?

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Yvonne Nussbaumer-Ochsner

Full Text Available Smoking is associated with a mixed inflammatory infiltrate in the airways. We evaluated whether airway inflammation in smokers is related to lung function parameters and inflammatory markers in exhaled breath.Thirty-seven smokers undergoing lung resection for primary lung cancer were assessed pre-operatively by lung function testing including single-breath-nitrogen washout test (sb-N2-test, measurement of fractional exhaled nitric oxide (FeNO and pH/8-isoprostane in exhaled breath condensate (EBC. Lung tissue sections containing cancer-free large (LA and small airways (SA were stained for inflammatory cells. Mucosal (MCT respectively connective tissue mast cells (MCTC and interleukin-17A (IL-17A expression by mast cells was analysed using a double-staining protocol.The median number of neutrophils, macrophages and mast cells infiltrating the lamina propria and adventitia of SA was higher than in LA. Both MCTC and MCT were higher in the lamina propria of SA compared to LA (MCTC: 49 vs. 27.4 cells/mm2; MCT: 162.5 vs. 35.4 cells/mm2; P<0.005 for both instances. IL-17A expression was predominantly detected in MCTC of LA. Significant correlations were found for the slope of phase III % pred. of the sb-N2-test (rs= -0.39, for the FEV1% pred. (rs= 0.37 and for FEV1/FVC ratio (rs=0.38 with MCT in SA (P<0.05 for all instances. 8-isoprostane concentration correlated with the mast cells in the SA (rs=0.44, there was no correlation for pH or FeNO with cellular distribution in SA.Neutrophils, macrophages and mast cells are more prominent in the SA indicating that these cells are involved in the development of small airway dysfunction in smokers. Among these cell types, the best correlation was found for mast cells with lung function parameters and inflammatory markers in exhaled breath. Furthermore, the observed predominant expression of IL-17A in mast cells warrants further investigation to elucidate their role in smoking-induced lung injury, despite the

Breath tests: principles, problems, and promise

International Nuclear Information System (INIS)

Lo, C.W.; Carter, E.A.; Walker, W.A.

1982-01-01

Breath tests rely on the measurement of gases produced in the intestine, absorbed, and expired in the breath. Carbohydrates, such as lactose and sucrose, can be administered in ysiologic doses; if malabsorbed, they will be metabolized to hydrogen by colonic bacteria. Since hydrogen is not produced by human metabolic reactions, a rise in breath hydrogen, as measured by gas chromatography, is evidence of carbohydrate malabsorption. Likewise, a rise in breath hydrogen marks the transit time of nonabsorbable carbohydrates such as lactulose through the small intestine into the colon. Simple end-expiratory interval collection into nonsiliconized vacutainer tubes has made these noninvasive tests quite convenient to perform, but various problems, including changes in stool pH intestinal motility, or metabolic rate, may influence results. Another group of breath tests uses substrates labeled with radioactive or stable isotopes of carbon. Labeled fat substrates such as trioctanoin, tripalmitin, and triolein do not produce the expected rise in labeled breath CO 2 if there is fat malabsorption. Bile acid malabsorption and small intestinal bacterial overgrowth can be measured with labeled cholylglycine or cholyltaurine. Labeled drugs such as aminopyrine, methacetin, and phenacetin can be used as an indication of drug metabolism and liver function. Radioactive substrates have been used to trace metabolic pathways and can be measured by scintillation counters. The availability of nonradioactive stable isotopes has made these ideal for use in children and pregnant women, but the cost of substrates and the mass spectrometers to measure them has so far limited their use to research centers. It is hoped that new techniques of processing and measurement will allow further realization of the exciting potential breath analysis has in a growing list of clinical applications

CEA, SCC and NSE levels in exhaled breath condensate--possible markers for early detection of lung cancer.

Science.gov (United States)

Zou, Yingchang; Wang, Lin; Zhao, Cong; Hu, Yanjie; Xu, Shan; Ying, Kejing; Wang, Ping; Chen, Xing

2013-12-01

Lung cancer (LC) is the leading cause of cancer-related death. The sensitive and non-invasive diagnostic tools in the early stage are still poor. We present a pilot study on the early diagnosis of LC by detecting markers in exhaled breath condensate (EBC). EBC samples were collected from 105 patients with LC and 56 healthy controls. We applied chemiluminescence immunoassay to detect CEA (carcinoembryonic antigen), SCC (squamous cell carcinoma) antigen and NSE (neuron specific enolase) in EBC and serum. Concentrations of markers were compared between independent groups and subgroups. A significantly higher concentration level of each marker was found in patients with LC than healthy controls. The areas under curve of receiver operating characteristic (ROC) curves were 0.800, 0.771, 0.659, 0.679, 0.636 and 0.626 for EBC-CEA, serum-CEA, EBC-SCC, serum-SCC, EBC-NSE and serum-NSE, respectively. Markers in EBC had a higher positive rate (PR) and were more specific to histologic types than markers in serum. In addition, multivariate analysis was performed to evaluate the association of presenting markers with the stages of non-small cell lung cancer (NSCLC). EBC-CEA showed the best predictive characteristic (p tumor markers in EBC may have a better diagnostic performance for LC than those in serum. With further investigation on the combination of markers in EBC, detection of EBC could probably be a novel and non-invasive method to detect NSCLC earlier.

Potential of Mass Spectrometry in Developing Clinical Laboratory Biomarkers of Nonvolatiles in Exhaled Breath.

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Beck, Olof; Olin, Anna-Carin; Mirgorodskaya, Ekaterina

2016-01-01

Exhaled breath contains nonvolatile substances that are part of aerosol particles of submicrometer size. These particles are formed and exhaled as a result of normal breathing and contain material from distal airways of the respiratory system. Exhaled breath can be used to monitor biomarkers of both endogenous and exogenous origin and constitutes an attractive specimen for medical investigations. This review summarizes the present status regarding potential biomarkers of nonvolatile compounds in exhaled breath. The field of exhaled breath condensate is briefly reviewed, together with more recent work on more selective collection procedures for exhaled particles. The relation of these particles to the surfactant in the terminal parts of the respiratory system is described. The literature on potential endogenous low molecular weight compounds as well as protein biomarkers is reviewed. The possibility to measure exposure to therapeutic and abused drugs is demonstrated. Finally, the potential future role and importance of mass spectrometry is discussed. Nonvolatile compounds exit the lung as aerosol particles that can be sampled easily and selectively. The clinical applications of potential biomarkers in exhaled breath comprise diagnosis of disease, monitoring of disease progress, monitoring of drug therapy, and toxicological investigations. © 2015 American Association for Clinical Chemistry.

The application of condensate water as an additional cooling media intermittently in condenser of a split air conditioning

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Ardita, I. N.; Subagia, I. W. A.

2018-01-01

The condensate water produced by indoor a split air conditioning is usually not utilized and thrown away into the environment. The result of measurement shows that the temperature of condensate water produced by split air conditioning is quite low, that is 19-22 °C at the rate of 16-20 mL / min and it has PH balance. Under such conditions, Air Condensate produced by split air conditioning should still be recovered as an additional cooling medium on the condenser. This research will re-investigate the use of condensate water as an intermittent additional cooling of the condenser to increase the cooling capacity and performance of the air conditioning system. This research is done by experimental method whose implementation includes; designing and manufacturing of experimental equipment, mounting measuring tools, experimental data retrieval, data processing and yield analysis. The experimental results show that the use of condensate water as an intermittent additional cooling medium on split air conditioning condenser can increase the refrigeration effect about 2%, cooling capacity about 4% and 7% of COP system. Experimental results also show a decrease in power consumption in the system compressor about 3%

Occupational asthma follow-up - which markers are elevated in exhaled breath condensate and plasma?

Czech Academy of Sciences Publication Activity Database

Pelclová, D.; Fenclová, Z.; Vlčková, Š.; Klusáčková, P.; Lebedová, J.; Syslová, K.; Běláček, J.; Kuzma, Marek; Navrátil, Tomáš; Zakharov, S.; Kačer, P.

2014-01-01

Roč. 27, č. 2 (2014), s. 206-215 ISSN 1232-1087 Institutional support: RVO:61388971 ; RVO:61388955 Keywords : occupational asthma * exhalted breath condesate * leukotrienes Subject RIV: EC - Immunology; CF - Physical ; Theoretical Chemistry (UFCH-W) Impact factor: 0.695, year: 2014

Modified Qigong Breathing Exercise for Reducing the Sense of Hunger on an Empty Stomach

Science.gov (United States)

Voroshilov, Alexander P.; Wang, Zhixin; Marchenko, Elena V.

2017-01-01

Background. The aims of this study were to determine whether a modified Qigong breathing exercise can reduce the sense of hunger and identify possible mechanisms. Methods. The results from the test group, which performed the exercise, are compared with the control group, which performed deep breathing. Intestinal pressure measurements, stomach pH monitoring, and participant surveys were used for assessment. Results. Stomach pH was increased by 3 (0.2) and intestinal pressure was reduced by 12 (0.5) mm Hg in the experimental group and did not change significantly in the control group. The study provides strong evidence that the exercise can significantly reduce, or even suppress the sense of hunger on an empty stomach. Conclusion. This breathing exercise provides comfort in different circumstances, such as lack of regular meals, limited volume or caloric diet, and even during temporary complete absence of food in therapeutic fasting. PMID:28497701

Excitations of Bose-Einstein condensates at finite temperatures

International Nuclear Information System (INIS)

Rusch, M.

2000-01-01

Recent experimental observations of collective excitations of Bose condensed atomic vapours have stimulated interest in the microscopic description of the dynamics of a Bose-Einstein condensate confined in an external potential. We present a finite temperature field theory for collective excitations of trapped Bose-Einstein condensates and use a finite-temperature linear response formalism, which goes beyond the simple mean-field approximation of the Gross-Pitaevskii equation. The effect of the non-condensed thermal atoms we include using perturbation theory in a quasiparticle basis. This presents a simple scheme to understand the interaction between condensate and non-condensed atoms and enables us to include the effect the condensate has on collision dynamics. At first we limit our treatment to the case of a spatially homogeneous Bose gas. We include the effect of pair and triplet anomalous averages and thus obtain a gapless theory for the excitations of a weakly interacting system, which we can link to well known results for Landau and Beliaev damping rates. A gapless theory for trapped systems with a static thermal component follows straightforwardly. We then investigate finite temperature excitations of a condensate in a spherically symmetric harmonic trap. We avoid approximations to the density of states and thus emphasise finite size aspects of the problem. We show that excitations couple strongly to a restricted number of modes, giving rise to resonance structure in their frequency spectra. Where possible we derive energy shifts and lifetimes of excitations. For one particular mode, the breathing mode, the effects of the discreteness of the system are sufficiently pronounced that the simple picture of an energy shift and width fails. Experiments in spherical traps have recently become feasible and should be able to test our detailed quantitative predictions. (author)

Breathing adapted radiotherapy for breast cancer: comparison of free breathing gating with the breath-hold technique

DEFF Research Database (Denmark)

Korreman, Stine Sofia; Pedersen, Anders N; Nøttrup, Trine Jakobi

2005-01-01

BACKGROUND AND PURPOSE: Adjuvant radiotherapy after breast-conserving surgery for breast cancer implies a risk of late cardiac and pulmonary toxicity. This is the first study to evaluate cardiopulmonary dose sparing of breathing adapted radiotherapy (BART) using free breathing gating......, and to compare this respiratory technique with voluntary breath-hold. PATIENTS AND METHODS: 17 patients were CT-scanned during non-coached breathing manoeuvre including free breathing (FB), end-inspiration gating (IG), end-expiration gating (EG), deep inspiration breath-hold (DIBH) and end-expiration breath......-hold (EBH). The Varian Real-time Position Management system (RPM) was used to monitor respiratory movement and to gate the scanner. For each breathing phase, a population based internal margin (IM) was estimated based on average chest wall excursion, and incorporated into an individually optimised three...

NEW METHODOLOGY FOR IDENTIFYING POTENTIAL HUMAN BIOMARKERS BY COLLECTION AND CONCENTRATION OF EXHALED BREATH CONDENSATE

Science.gov (United States)

In many studies of human exposure, the measurement of pollutant chemicals in the environment (air, water, food, soil, etc.) is being supplemented by their additional measurement in biological media such as human breath, blood, and urine. This allows an unambiguous confirmation...

Carbogen Breathing Differentially Enhances Blood Plasma Volume and 5-Fluorouracil Uptake in Two Murine Colon Tumor Models with a Distinct Vascular Structure

Directory of Open Access Journals (Sweden)

Hanneke W.M. van Laarhoven

2006-06-01

Full Text Available For the systemic treatment of colorectal cancer, 5-fluorouracil (FU-based chemotherapy is the standard. However, only a subset of patients responds to chemotherapy. Breathing of carbogen (95% O2 and 5% CO2 may increase the uptake of FU through changes in tumor physiology. This study aims to monitor in animal models in vivo the effects of carbogen breathing on tumor blood plasma volume, pH, and energy status, and on FU uptake and metabolism in two colon tumor models C38 and C26a, which differ in their vascular structure and hypoxic status. Phosphorus-31 magnetic resonance spectroscopy (MRS was used to assess tumor pH and energy status, and fluorine-19 MRS was used to follow FU uptake and metabolism. Advanced magnetic resonance imaging methods using ultrasmall particles of iron oxide were performed to assess blood plasma volume. The results showed that carbogen breathing significantly decreased extracellular pH and increased tumor blood plasma volume and FU uptake in tumors. These effects were most significant in the C38 tumor line, which has the largest relative vascular area. In the C26a tumor line, carbogen breathing increased tumor growth delay by FU. In this study, carbogen breathing also enhanced systemic toxicity by FU.

Condensation mechanisms of tetravalent technetium in chloride media

International Nuclear Information System (INIS)

Poineau, F.

2004-10-01

In deep storage technetium can exist in degree IV or III. Recent studies on Tc(IV) have shown that Tc n O y (4n-2y)+ , Tc IV (μ-O) 2 Tc IV structure, is a precursor for precipitation of TcO 2 . Few data are available on Tc n O y (4n-2y)+ Subject of this thesis is the mechanism of condensation of Tc(IV) leading to this form. Kinetic studies have shown that the condensation of Tc IV Cl 5 (H 2 O) - in chloride media leads to a dimer. XAS studies resulted in a linear structure Tc IV -O-Tc IV . This compound, formulated as Tc 2 OCl 10 4- , is stable at pH = 0.3, it undergoes cyclization to Tc n O y (4n-2y)+ at pH =1.5 and is oxidized to TcO 4 - under α radiation. In 3 M chloride media, TcO 2 lead to formation Tc 2 OCl 10 4- at pH = 0.3 and to Tc n O y (4n-2y)+ at pH = 1.5. An electrochemical cell permitting 'in situ' XAS measurement was developed. XANES studies have shown that the reduction of Tc(VII) lead to a Tc(IV)/Tc(III) mixture. (author)

Condensation of rye chromatin in somatic interphase nuclei of Ph1 and ph1b wheat

Czech Academy of Sciences Publication Activity Database

Kopecký, David; Allen, D.C.; Duchoslav, M.; Doležel, Jaroslav; Lukaszewski, A.J.

2007-01-01

Roč. 119, 3-4 (2007), s. 263-267 ISSN 1424-8581 R&D Projects: GA MŠk(CZ) LC06004 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje Keywords : hexaploid wheat * Ph1 and ph1b * rye chromatin Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.402, year: 2007

Mechanical ventilation with heated humidifiers: measurements of condensed water mass within the breathing circuit according to ventilatory settings

International Nuclear Information System (INIS)

Schena, E; Saccomandi, P; Cappelli, S; Silvestri, S

2013-01-01

Heated wire humidifiers (HWHs) are widely used to heat and humidify gases during mechanical ventilation. The control strategy implemented on commercial HWHs, based on maintaining constant gas temperature at the chamber outlet, shows weaknesses: humidifying performances depend on environmental temperature and ventilatory settings, and often condensation occurs. Herein, we analyzed in vitro HWH performances focusing on the condensation amount according to ventilatory settings. We used a physical model to define the parameters which mainly influence the HWH performances. In order to investigate the influence of minute volume (MV) and frequency rate (f r ) on condensation, the other influencing parameters were kept constant during experiments, and we introduced a novel approach to estimate the condensation. The method, based on measuring the condensed vapor mass (Δm), provided more objective information than the visual-based scale used in previous studies. Thanks to both the control of other influencing factors and the accurate Δm measures, the investigation showed the Δm increase with MV and f r . Substantial condensation after 7 h of ventilation and the influence of MV and f r on Δm (i.e., Δm = 3 g at MV = 1.5 L min −1 and f r = 8 bpm and Δm = 9.4 g at MV = 8 L min −1 and f r = 20 bpm) confirm the weaknesses of 'single-point temperature' control strategies. (paper)

Medical Issues: Breathing

Science.gov (United States)

... Information Packets Equipment Pool Living With SMA Medical Issues Palliative Breathing Orthopedics Nutrition Equipment Daily Life At ... curesma.org > support & care > living with sma > medical issues > breathing Breathing Breathing problems are the most common ...

Kidney motion during free breathing and breath hold for MR-guided radiotherapy

International Nuclear Information System (INIS)

Stam, Mette K; Van Vulpen, Marco; Intven, Martijn; Crijns, Sjoerd P M; Lagendijk, Jan J W; Raaymakers, Bas W; Barendrecht, Maurits M; Zonnenberg, Bernard A

2013-01-01

Current treatments for renal cell carcinoma have a high complication rate due to the invasiveness of the treatment. With the MRI-linac it may be possible to treat renal tumours non-invasively with high-precision radiotherapy. This is expected to reduce complications. To deliver a static dose distribution, radiation gating will be used. In this study the reproducibility and efficiency of free breathing gating and a breath hold treatment of the kidney was investigated. For 15 patients with a renal lesion the kidney motion during 2 min of free breathing and 10 consecutive expiration breath holds was studied with 2D cine MRI. The variability in kidney expiration position and treatment efficiency for gating windows of 1 to 20 mm was measured for both breathing patterns. Additionally the time trend in free breathing and the variation in expiration breath hold kidney position with baseline shift correction was determined. In 80% of the patients the variation in expiration position during free breathing is smaller than 2 mm. No clinically relevant time trends were detected. The variation in expiration breath hold is for all patients larger than the free breathing expiration variation. Gating on free breathing is, for gating windows of 1 to 5 mm more efficient than breath hold without baseline correction. When applying a baseline correction to the breath hold it increases the treatment efficiency. The kidney position is more reproducible in expiration free breathing than non-guided expiration breath hold. For small gating windows it is also more time efficient. Since free breathing also seems more comfortable for the patients it is the preferred breathing pattern for MRI-Linac treatments of the kidney. (paper)

Evaluation of oxidative status with exhaled breath 8-isoprostane levels in patients with hyperthyroidism.

Science.gov (United States)

Bastug, Emrah; Tasliyurt, Turker; Kutluturk, Faruk; Sahin, Safak; Yilmaz, Ayse; Sivgin, Hakan; Yelken, Berna Murat; Ozturk, Banu; Yilmaz, Abdulkerim; Sahin, Semsettin

2013-12-01

Studies conducted so far on the effect of hyperthyroidism on oxidative stress (OS) have employed blood and urine samples. Exhaled Breath Condensate (EBC) is a non-invasive technique used to take sample from lungs to determine many biological indications. The aim of the present study was determine the possibility of using 8- isoprostane levels in EBC as an indicator of OS in hyperthyroid patients. The present study was performed on 42 patients with hyperthyroidism and 42 healthy control subjects. Hyperthyroid patients included patients with newly diagnosed Graves' disease, toxic multinodular goiter and toxic adenoma. Exhaled breath condensates were collected from patients in each group using a condensing device. 8- isoprostane levels as an indicator of OS in EBC were detected via immunoassay method. Hyperthyroid patients and control groups had 8-isoprostane levels of 6.08±6.31 and 1.56±0.88 pg/ml, respectively. The difference between patient and control groups was statistically significant (phyperthyroid patients, eleven had Graves', 21 multinodular goiter, and 10 toxic adenoma diagnosis. There were no significant differences among patients of different diagnoses for 8-isoprostane levels (p=0.541). No significant correlations were found between 8-isoprostane and free thyroxine (fT4) or thyroid stimulating hormone (TSH) levels. In the present study, 8-isoprostane levels in EBC of hyperthyroid patients were found to be significantly higher than that in healthy control group. This study is important in that it is the first to evaluate the effects on respiratory system of elevated OS of hyperthyroidism in EBC.

Effects of condensate in the exhalation limb of neonatal circuits on airway pressure during bubble CPAP.

Science.gov (United States)

Youngquist, Tiffany M; Richardson, C Peter; Diblasi, Robert M

2013-11-01

Bubble CPAP is frequently used in spontaneously breathing infants with lung disease. Often bubble CPAP systems lack pressure alarms and pressure-release valves. We observed a large volume of condensate in the exhalation limb of a patient circuit and conducted a series of experiments to test the hypothesis that accumulated condensate could affect delivered pressures. An anatomically accurate nasal airway model of a preterm infant was attached to a spontaneously breathing lung model. A bubble CPAP system was attached to the nasal airway with bi-nasal short prongs, and the rate of fluid condensation was measured. Next, tracheal pressures were monitored digitally to detect changes in airway pressure related to condensate accumulation. Measurements were obtained with volumes of 0, 5, 10, 15, and 20 mL of water in the exhalation limb, at flows of 4, 6, 8, and 10 L/min. Measurements with 20 mL in the exhalation limb were recorded with and without a pressure-relief valve in the circuit. The rate of condensate accumulation was 3.8 mL/h. At volumes of ≥ 10 mL, noticeable alterations in the airway pressure waveforms and significant increases in mean tracheal pressure were observed. The pressure-relief valve effectively attenuated peak tracheal pressure, but only decreased mean pressure by 0.5-1.5 cm H2O. Condensate in the exhalation limb of the patient circuit during bubble CPAP can significantly increase pressure delivered to the patient. The back and forth movement of this fluid causes oscillations in airway pressure that are much greater than the oscillations created by gas bubbling out the exhalation tube into the water bath. We recommend continuously monitoring pressure at the nasal airway interface, placing an adjustable pressure-relief valve in the circuit, set to 5 cm H2O above the desired mean pressure, and emptying fluid from the exhalation limb every 2-3 hours.

Anoxia and Acidosis Tolerance of the Heart in an Air-Breathing Fish (Pangasianodon hypophthalmus).

Science.gov (United States)

Joyce, William; Gesser, Hans; Bayley, Mark; Wang, Tobias

2015-01-01

Air breathing has evolved repeatedly in fishes and may protect the heart during stress. We investigated myocardial performance in the air-breathing catfish Pangasianodon hypophthalmus, a species that can withstand prolonged exposure to severe hypoxia and acidosis. Isometric ventricular preparations were exposed to anoxia, lactic acidosis, hypercapnic acidosis, and combinations of these treatments. Ventricular preparations were remarkably tolerant to anoxia, exhibiting an inotropic reduction of only 40%, which fully recovered during reoxygenation. Myocardial anoxia tolerance was unaffected by physiologically relevant elevations of bicarbonate concentration, in contrast to previous results in other fishes. Both lactic acidosis (5 mM; pH 7.10) and hypercapnic acidosis (10% CO2; pH 6.70) elicited a biphasic response, with an initial and transient decrease in force followed by overcompensation above control values. Spongy myocardial preparations were significantly more tolerant to hypercapnic acidosis than compact myocardial preparations. While ventricular preparations were tolerant to the isolated effects of anoxia and acidosis, their combination severely impaired myocardial performance and contraction kinetics. This suggests that air breathing may be a particularly important myocardial oxygen source during combined anoxia and acidosis, which may occur during exercise or environmental stress.

Poly arginine-graphene quantum dots as a biocompatible and non-toxic nanocomposite: Layer-by-layer electrochemical preparation, characterization and non-invasive malondialdehyde sensory application in exhaled breath condensate

Energy Technology Data Exchange (ETDEWEB)

Hasanzadeh, Mohammad, E-mail: hasanzadehm@tbzmed.ac.ir [Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz 51664 (Iran, Islamic Republic of); Mokhtari, Fozieh [Pharmaceutical Analysis Research Center, Tabriz University of Medical Sciences, Tabriz (Iran, Islamic Republic of); Department of Biochemistry, Higher Education Institute of Rab-Rashid, Tabriz (Iran, Islamic Republic of); Shadjou, Nasrin [Department of Nanochemistry, Nano Technology Research Center, Urmia University, Urmia 57154 (Iran, Islamic Republic of); Department of Nano Technology, Faculty of Science, Urmia University, Urmia 57154 (Iran, Islamic Republic of); Eftekhari, Aziz [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tabriz University of Medical Sciences, 51664-14766 Tabriz (Iran, Islamic Republic of); Mokhtarzadeh, Ahad [Department of Biochemistry, Higher Education Institute of Rab-Rashid, Tabriz (Iran, Islamic Republic of); School of Medicine, Gonabad University of Medical Sciences, Gonabad (Iran, Islamic Republic of); Jouyban-Gharamaleki, Vahid [Department of Mechatronic Engineering, International Campus, University of Tabriz, Tabriz (Iran, Islamic Republic of); Mahboob, Soltanali [Department of Biochemistry, Higher Education Institute of Rab-Rashid, Tabriz (Iran, Islamic Republic of)

2017-06-01

This study reports on the electropolymerization of a low toxic and biocompatible polymer with entitle poly arginine-graphene quantum dots (PARG-GQDs) as a novel strategy for surface modification of glassy carbon (GC) surface and preparation a new interface for biomedical application. The fabrication of PARG-GQDs on GCE was performed using Layer-by-layer regime. Scanning electron microscopy (SEM) was confirmed dispersion of GQDs on the surface of PARG which lead to increase of surface coverage of PARG. The redox behavior of prepared sensor was then characterized by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry (CHA), square wave voltammetry (SWV), linear sweep voltammetry (LSV). The electroactivity of PARG-GQDs coating towards detection and determination of malondialdehyde (MDA) as one of the most common biomarkers of oxidative stress, was then studied. Then, application of prepared sensor for the detection of MDA in exhaled breath condensate (EBC) is described. Electrochemical based sensor shows the lower limit of quantification (LLOQ) were 0.329 nanomolar. This work is the first report on the integration of GQDs to poly amino acids. Further development can lead to monitoring of MDA or other exhaled breath biomarkers by GQDs functionalized poly amino acids in EBC using electrochemical methods. - Highlights: • Simple and one pot electropolymerization was used to preparation of Poly arginine-graphene quantum dots. • PARG-GQDs-GCE shows an excellent electroactivity towards malondialdehyde. • High sensitivity and efficiency is achieved through a simple method of modification. • MDA electrochemical sensor for a direct evaluation of oxidative stress in EBC media is possible.

Poly arginine-graphene quantum dots as a biocompatible and non-toxic nanocomposite: Layer-by-layer electrochemical preparation, characterization and non-invasive malondialdehyde sensory application in exhaled breath condensate

International Nuclear Information System (INIS)

Hasanzadeh, Mohammad; Mokhtari, Fozieh; Shadjou, Nasrin; Eftekhari, Aziz; Mokhtarzadeh, Ahad; Jouyban-Gharamaleki, Vahid; Mahboob, Soltanali

2017-01-01

This study reports on the electropolymerization of a low toxic and biocompatible polymer with entitle poly arginine-graphene quantum dots (PARG-GQDs) as a novel strategy for surface modification of glassy carbon (GC) surface and preparation a new interface for biomedical application. The fabrication of PARG-GQDs on GCE was performed using Layer-by-layer regime. Scanning electron microscopy (SEM) was confirmed dispersion of GQDs on the surface of PARG which lead to increase of surface coverage of PARG. The redox behavior of prepared sensor was then characterized by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry (CHA), square wave voltammetry (SWV), linear sweep voltammetry (LSV). The electroactivity of PARG-GQDs coating towards detection and determination of malondialdehyde (MDA) as one of the most common biomarkers of oxidative stress, was then studied. Then, application of prepared sensor for the detection of MDA in exhaled breath condensate (EBC) is described. Electrochemical based sensor shows the lower limit of quantification (LLOQ) were 0.329 nanomolar. This work is the first report on the integration of GQDs to poly amino acids. Further development can lead to monitoring of MDA or other exhaled breath biomarkers by GQDs functionalized poly amino acids in EBC using electrochemical methods. - Highlights: • Simple and one pot electropolymerization was used to preparation of Poly arginine-graphene quantum dots. • PARG-GQDs-GCE shows an excellent electroactivity towards malondialdehyde. • High sensitivity and efficiency is achieved through a simple method of modification. • MDA electrochemical sensor for a direct evaluation of oxidative stress in EBC media is possible.

Study on corrosion of thermal power plant condenser tubes

Energy Technology Data Exchange (ETDEWEB)

Mohammadi, Abdolreza Rashidi; Zhaam, Ali Akbar [Niroo Research Institute, end of Poonak Bakhtari blvd., Shahrak Ghods, Tehran (Iran)

2004-07-01

The aim of this investigation is to study kinds of corrosion mechanisms in thermal power plant condenser tubes. Condenser is a shell and tube heat exchanger in which cooling water flows through its tubes. While the steam from low pressure turbine passes within condenser tubes, it is condensed by cooling water. The exhausted steam from low pressure turbine is condensed on external surface of condenser tubes and heat is transferred to cooling water which flow into tubes. Tubes composition is usually copper-based alloys, stainless steel or titanium. Annual damages due to corrosion cause much cost for replacement and repairing metallic equipment and installations in electric power industry. Because of existence of different contaminants in water and steam cycle, condenser tubes surfaces are exposed to corrosion. Contaminants like oxygen, carbon dioxide, chloride ion and ammonia in water and steam cycle originate several damages such as pitting and crevice corrosion, erosion, galvanic attack, SCC, condensed corrosion, de-alloying in thermal power plant condenser. The paper first states how corrosion damage takes place in condensers and then introduces types of usual alloys used in condensers and also their corrosion behavior. In continuation, a brief explanation is presented about kinds of condenser failures due to corrosion. Then, causes and locations of different mechanisms of corrosion events on condenser tubes and effects of different parameters such as composition, temperature, chloride and sulfide ion concentration, pH, water velocity and biological precipitation are examined and finally protection methods are indicated. Also some photos of tubes specimens related to power plants are studied and described in each case of mentioned mechanisms. (authors)

Acid-sensing ion channels contribute to chemosensitivity of breathing-related neurons of the nucleus of the solitary tract.

Science.gov (United States)

Huda, Rafiq; Pollema-Mays, Sarah L; Chang, Zheng; Alheid, George F; McCrimmon, Donald R; Martina, Marco

2012-10-01

Cellular mechanisms of central pH chemosensitivity remain largely unknown. The nucleus of the solitary tract (NTS) integrates peripheral afferents with central pathways controlling breathing; NTS neurons function as central chemosensors, but only limited information exists concerning the ionic mechanisms involved. Acid-sensing ion channels (ASICs) mediate chemosensitivity in nociceptive terminals, where pH values ∼6.5 are not uncommon in inflammation, but are also abundantly expressed throughout the brain where pHi s tightly regulated and their role is less clear. Here we test the hypothesis that ASICs are expressed in NTS neurons and contribute to intrinsic chemosensitivity and control of breathing. In electrophysiological recordings from acute rat NTS slices, ∼40% of NTS neurons responded to physiological acidification (pH 7.0) with a transient depolarization. This response was also present in dissociated neurons suggesting an intrinsic mechanism. In voltage clamp recordings in slices, a pH drop from 7.4 to 7.0 induced ASIC-like inward currents (blocked by 100 μM amiloride) in ∼40% of NTS neurons, while at pH ≤ 6.5 these currents were detected in all neurons tested; RT-PCR revealed expression of ASIC1 and, less abundantly, ASIC2 in the NTS. Anatomical analysis of dye-filled neurons showed that ASIC-dependent chemosensitive cells (cells responding to pH 7.0) cluster dorsally in the NTS. Using in vivo retrograde labelling from the ventral respiratory column, 90% (9/10) of the labelled neurons showed an ASIC-like response to pH 7.0, suggesting that ASIC currents contribute to control of breathing. Accordingly, amiloride injection into the NTS reduced phrenic nerve activity of anaesthetized rats with an elevated arterial P(CO(2)) .

Landau damping of transverse quadrupole oscillations of an elongated Bose-Einstein condensate

International Nuclear Information System (INIS)

Guilleumas, M.; Pitaevskii, L.P.

2003-01-01

We have studied the interaction between the low-lying transverse collective oscillations and the thermal excitations of an elongated Bose-Einstein condensate by means of perturbation theory. We consider a cylindrical trapped condensate and calculate the transverse elementary excitations at zero temperature by solving the linearized Gross-Pitaevskii equations in two dimensions (2D). We use them to calculate the matrix elements between the thermal excited states and the quasi-2D collective modes. The Landau damping of transverse collective modes is studied as a function of temperature. At low temperatures, the corresponding damping rate is in agreement with the experimental data for the decay of the transverse quadrupole mode, but it is too small to explain the observed slow decay of the transverse breathing mode. The reason for this discrepancy is discussed

Rapid shallow breathing

Science.gov (United States)

Tachypnea; Breathing - rapid and shallow; Fast shallow breathing; Respiratory rate - rapid and shallow ... Shallow, rapid breathing has many possible medical causes, including: Asthma Blood clot in an artery in the ...

Evolution of clinical and environmental health applications of exhaled breath research: Review of methods and instrumentation for gas-phase, condensate, and aerosols

Science.gov (United States)

Human breath, along with urine and blood, has long been one of the three major biological media for assessing human health and environmental exposure. In fact, the detection of odor on human breath, as described by Hippocrates in 400 BC, is considered the first analytical healt...

Collecting Protein Biomarkers in Breath Using Electret Filters: A Preliminary Method on New Technical Model and Human Study.

Directory of Open Access Journals (Sweden)

Wang Li

Full Text Available Biomarkers in exhaled breath are useful for respiratory disease diagnosis in human volunteers. Conventional methods that collect non-volatile biomarkers, however, necessitate an extensive dilution and sanitation processes that lowers collection efficiencies and convenience of use. Electret filter emerged in recent decade to collect virus biomarkers in exhaled breath given its simplicity and effectiveness. To investigate the capability of electret filters to collect protein biomarkers, a model that consists of an atomizer that produces protein aerosol and an electret filter that collects albumin and carcinoembryonic antigen-a typical biomarker in lung cancer development- from the atomizer is developed. A device using electret filter as the collecting medium is designed to collect human albumin from exhaled breath of 6 volunteers. Comparison of the collecting ability between the electret filter method and other 2 reported methods is finally performed based on the amounts of albumin collected from human exhaled breath. In conclusion, a decreasing collection efficiency ranging from 17.6% to 2.3% for atomized albumin aerosol and 42% to 12.5% for atomized carcinoembryonic antigen particles is found; moreover, an optimum volume of sampling human exhaled breath ranging from 100 L to 200 L is also observed; finally, the self-designed collecting device shows a significantly better performance in collecting albumin from human exhaled breath than the exhaled breath condensate method (p0.05. In summary, electret filters are potential in collecting non-volatile biomarkers in human exhaled breath not only because it was simpler, cheaper and easier to use than traditional methods but also for its better collecting performance.

Condensation model for the ESBWR passive condensers

International Nuclear Information System (INIS)

Revankar, S. T.; Zhou, W.; Wolf, B.; Oh, S.

2012-01-01

In the General Electric's Economic simplified boiling water reactor (GE-ESBWR) the passive containment cooling system (PCCS) plays a major role in containment pressure control in case of an loss of coolant accident. The PCCS condenser must be able to remove sufficient energy from the reactor containment to prevent containment from exceeding its design pressure following a design basis accident. There are three PCCS condensation modes depending on the containment pressurization due to coolant discharge; complete condensation, cyclic venting and flow through mode. The present work reviews the models and presents model predictive capability along with comparison with existing data from separate effects test. The condensation models in thermal hydraulics code RELAP5 are also assessed to examine its application to various flow modes of condensation. The default model in the code predicts complete condensation well, and basically is Nusselt solution. The UCB model predicts through flow well. None of condensation model in RELAP5 predict complete condensation, cyclic venting, and through flow condensation consistently. New condensation correlations are given that accurately predict all three modes of PCCS condensation. (authors)

Imposed Work of Breathing and Breathing Comfort of Nonintubated Volunteers Breathing with Three Portable Ventilators and a Critical Care Ventilator

National Research Council Canada - National Science Library

Austin, Paul

2001-01-01

.... The purpose of this study was to assess the imposed inspiratory work of breathing and breathing comfort of nonintubated healthy volunteers breathing spontaneously through three portable ventilators...

Condensers

International Nuclear Information System (INIS)

Andrieux, M.B.

1984-01-01

Characteristics of the condenser cooling waters of various French 900 MW nuclear power plants. Design and description of various types of condensers: condensers feeded directly with river water, condensers feeded by cooling towers, condensers feeded with sea water of brackish water. Presentation of the main problems encountered with the brass bundles (ammoniacal corrosion, erosion of the peripheral tubes, vibrations of the tubes), with the titanium bundles, with the tubular plates, the tubes-tubular plates assemblies, the coatings of the condenser water chamber (sea water), the vapor by-pass and with the air inlet. Analysis of the in service performances such as condensation pressure, oxygen content and availability [fr

'Breath figure' PLGA films as implant coatings for controlled drug release

Science.gov (United States)

Ponnusamy, Thiruselvam

The breath figure method is a versatile and facile approach of generating ordered micro and nanoporous structures in polymeric materials. When a polymer solution (dissolved in a high vapor pressure organic solvent) is evaporated out in the presence of a moist air stream, the evaporative cooling effect causes the condensation and nucleation of water droplets onto the polymer solution surface. This leads to the formation of an imprinted porous structure upon removal of the residual solvent and water. The facile removal of the water droplet template leaving its structural imprint is a specifically appealing aspect of the breath figure film technology. The first part of the dissertation work involves the fabrication of drug loaded breath figure thin films and its utilization as a controlled drug release carrier and biomaterial scaffold. In a single fabrication step, single layer/multilayer porous thin films were designed and developed by combining the breath figure process and a modified spin or dip coating technique. Using biodegradable polymers such as poly (lactic-co-glycolic acid) (PLGA) and poly (ethylene glycol) (PEG), drug loaded films were fabricated onto FDA approved medical devices (the Glaucoma drainage device and the Surgical hernia mesh). The porosity of the films is in the range of 2-4 microm as characterized by scanning electron microscope. The drug coated medical implants were characterized for their surface and bulk morphology, the degradation rate of the film, drug release rate and cell cytotoxicity. The results suggest that the use of breath figure morphologies in biodegradable polymer films adds an additional level of control to drug release. In comparison to non-porous films, the breath figure films showed an increased degradation and enhanced drug release. Furthermore, the porous nature of the film was investigated as a biomaterial scaffold to construct three dimensional in vitro tissue model systems. The breath figure film with interconnected

Intracellular pH in human brain measured by P-31 MR spectroscopy during changes in arterial CO/sub 2/ tension

International Nuclear Information System (INIS)

Jensen, K.E.; Thomsen, C.; Henriksen, O.

1987-01-01

Six healthy volunteers were examined. A 1.5-T Siemens whole-body scanner was used. A three-turn solenoid surface coil was used. Sixty-four acquisitions with a repetition time of 6 seconds were recorded. The subjects hyperventilated and inhaled air with 5% and 7% CO/sub 2/. The breathing of air with 5% CO/sub 2/ resulted in an arterial blood tension of 40 mm Hg, and no changes in pH could be detected. Breathing of air with 7% CO/sub 2/ resulted in arterial tension of 55 mm Hg and gave a decrease of 0.1 pH unit. The spectra after 15 minutes of hyperventilation showed an increase of 0.1 pH unit

Secondhand smoke exposure induces acutely airway acidification and oxidative stress.

Science.gov (United States)

Kostikas, Konstantinos; Minas, Markos; Nikolaou, Eftychia; Papaioannou, Andriana I; Liakos, Panagiotis; Gougoura, Sofia; Gourgoulianis, Konstantinos I; Dinas, Petros C; Metsios, Giorgos S; Jamurtas, Athanasios Z; Flouris, Andreas D; Koutedakis, Yiannis

2013-02-01

Previous studies have shown that secondhand smoke induces lung function impairment and increases proinflammatory cytokines. The aim of the present study was to evaluate the acute effects of secondhand smoke on airway acidification and airway oxidative stress in never-smokers. In a randomized controlled cross-over trial, 18 young healthy never-smokers were assessed at baseline and 0, 30, 60, 120, 180 and 240 min after one-hour secondhand smoke exposure at bar/restaurant levels. Exhaled NO and CO measurements, exhaled breath condensate collection (for pH, H(2)O(2) and NO(2)(-)/NO(3)(-) measurements) and spirometry were performed at all time-points. Secondhand smoke exposure induced increases in serum cotinine and exhaled CO that persisted until 240 min. Exhaled breath condensate pH decreased immediately after exposure (p secondhand smoke induced airway acidification and increased airway oxidative stress, accompanied by significant impairment of lung function. Despite the reversal in EBC pH and lung function, airway oxidative stress remained increased 4 h after the exposure. Clinical trial registration number (EudraCT): 2009-013545-28. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bose-Einstein condensate collapse and dynamical squeezing of vacuum fluctuations

International Nuclear Information System (INIS)

Calzetta, E.A.; Hu, B.L.

2003-01-01

We analyze the phenomena of condensate collapse, as described by Donley et al. [Nature 412, 295 (2001)] and N. Claussen [Ph. D thesis, University of Colorado, 2003 (unpublished)] by focusing on the behavior of excitations or fluctuations above the condensate, as driven by the dynamics of the condensate, rather than the dynamics of the condensate alone or the kinetics of the atoms. The dynamics of the condensate squeezes and amplifies the quantum excitations, mixing the positive and negative frequency components of their wave functions thereby creating particles that appear as bursts and jets. By analyzing the changing amplitude and particle content of these excitations, our simple physical picture explains well the overall features of the collapse phenomena and provides excellent quantitative fits with experimental data on several aspects, such as the scaling behavior of the collapse time and the number of particles in the jet. The prediction of the bursts at this level of approximation is less than satisfactory but may be improved by including the backreaction of the excitations on the condensate. The mechanism behind the dominant effect--parametric amplification of vacuum fluctuations and freezing of modes outside of horizon--is similar to that of cosmological particle creation and structure formation in a rapid quench (which is fundamentally different from Hawking radiation in black holes). This shows that Bose-Einstein condensate dynamics is a promising venue for doing 'laboratory cosmology'

Excretory nitrogen metabolism and defence against ammonia toxicity in air-breathing fishes.

Science.gov (United States)

Chew, S F; Ip, Y K

2014-03-01

With the development of air-breathing capabilities, some fishes can emerge from water, make excursions onto land or even burrow into mud during droughts. Air-breathing fishes have modified gill morphology and morphometry and accessory breathing organs, which would tend to reduce branchial ammonia excretion. As ammonia is toxic, air-breathing fishes, especially amphibious ones, are equipped with various strategies to ameliorate ammonia toxicity during emersion or ammonia exposure. These strategies can be categorized into (1) enhancement of ammonia excretion and reduction of ammonia entry, (2) conversion of ammonia to a less toxic product for accumulation and subsequent excretion, (3) reduction of ammonia production and avoidance of ammonia accumulation and (4) tolerance of ammonia at cellular and tissue levels. Active ammonia excretion, operating in conjunction with lowering of ambient pH and reduction in branchial and cutaneous NH₃ permeability, is theoretically the most effective strategy to maintain low internal ammonia concentrations. NH₃ volatilization involves the alkalization of certain epithelial surfaces and requires mechanisms to prevent NH₃ back flux. Urea synthesis is an energy-intensive process and hence uncommon among air-breathing teleosts. Aestivating African lungfishes detoxify ammonia to urea and the accumulated urea is excreted following arousal. Reduction in ammonia production is achieved in some air-breathing fishes through suppression of amino acid catabolism and proteolysis, or through partial amino acid catabolism leading to alanine formation. Others can slow down ammonia accumulation through increased glutamine synthesis in the liver and muscle. Yet, some others develop high tolerance of ammonia at cellular and tissue levels, including tissues in the brain. In summary, the responses of air-breathing fishes to ameliorate ammonia toxicity are many and varied, determined by the behaviour of the species and the nature of the environment in

Phase Transitions of the Polariton Condensate in 2D Dirac Materials.

Science.gov (United States)

Lee, Ki Hoon; Lee, Changhee; Min, Hongki; Chung, Suk Bum

2018-04-13

For the quantum well in an optical microcavity, the interplay of the Coulomb interaction and the electron-photon (e-ph) coupling can lead to the hybridizations of the exciton and the cavity photon known as polaritons, which can form the Bose-Einstein condensate above a threshold density. Additional physics due to the nontrivial Berry phase comes into play when the quantum well consists of the gapped two-dimensional Dirac material such as the transition metal dichalcogenide MoS_{2} or WSe_{2}. Specifically, in forming the polariton, the e-ph coupling from the optical selection rule due to the Berry phase can compete against the Coulomb electron-electron (e-e) interaction. We find that this competition gives rise to a rich phase diagram for the polariton condensate involving both topological and symmetry breaking phase transitions, with the former giving rise to the quantum anomalous Hall and the quantum spin Hall phases.

Phase Transitions of the Polariton Condensate in 2D Dirac Materials

Science.gov (United States)

Lee, Ki Hoon; Lee, Changhee; Min, Hongki; Chung, Suk Bum

2018-04-01

For the quantum well in an optical microcavity, the interplay of the Coulomb interaction and the electron-photon (e -ph) coupling can lead to the hybridizations of the exciton and the cavity photon known as polaritons, which can form the Bose-Einstein condensate above a threshold density. Additional physics due to the nontrivial Berry phase comes into play when the quantum well consists of the gapped two-dimensional Dirac material such as the transition metal dichalcogenide MoS2 or WSe2 . Specifically, in forming the polariton, the e -ph coupling from the optical selection rule due to the Berry phase can compete against the Coulomb electron-electron (e -e ) interaction. We find that this competition gives rise to a rich phase diagram for the polariton condensate involving both topological and symmetry breaking phase transitions, with the former giving rise to the quantum anomalous Hall and the quantum spin Hall phases.

In vivo proton MRS of normal pancreas metabolites during breath-holding and free-breathing

International Nuclear Information System (INIS)

Su, T.-H.; Jin, E.-H.; Shen, H.; Zhang, Y.; He, W.

2012-01-01

Aim: To characterize normal pancreas metabolites using in vivo proton magnetic resonance spectroscopy ( 1 H MRS) at 3 T under conditions of breath-holding and free-breathing. Materials and methods: The pancreases of 32 healthy volunteers were examined using 1 H MRS during breath-holding and free-breathing acquisitions in a single-voxel point-resolved selective spectroscopy sequence (PRESS) technique using a 3 T MRI system. Resonances were compared between paired spectra of the two breathing modes. Furthermore, correlations between lipid (Lip) content and age, body-mass index (BMI), as well as choline (Cho) peak visibility of the normal pancreas were analysed during breath-holding. Results: Twenty-nine pairs of spectra were successfully obtained showing three major resonances, Lip, Cho, cholesterol and the unsaturated parts of the olefinic region of fatty acids (Chol + Unsat). Breath-hold spectra were generally better, with higher signal-to-noise ratios (SNR; Z=–2.646, p = 0.008) and Cho peak visible status (Z=–2.449, p = 0.014). Correlations were significant between spectra acquired by the two breathing modes, especially for Lip height, Lip area, and the area of other peaks at 1.9–4.1 ppm. However, the Lip resonance was significantly different between the spectra of the two breathing modes (p 1 H MRS of the normal pancreas at 3 T is technically feasible and can characterize several metabolites. 1 H MRS during breath-holding acquisition is superior to that during free-breathing acquisition.

Is breath acetone a biomarker of diabetes? A historical review on breath acetone measurements.

Science.gov (United States)

Wang, Zhennan; Wang, Chuji

2013-09-01

Since the ancient discovery of the 'sweet odor' in human breath gas, pursuits of the breath analysis-based disease diagnostics have never stopped. Actually, the 'smell' of the breath, as one of three key disease diagnostic techniques, has been used in Eastern-Medicine for more than three thousand years. With advancement of measuring technologies in sensitivity and selectivity, more specific breath gas species have been identified and established as a biomarker of a particular disease. Acetone is one of the breath gases and its concentration in exhaled breath can now be determined with high accuracy using various techniques and methods. With the worldwide prevalence of diabetes that is typically diagnosed through blood testing, human desire to achieve non-blood based diabetic diagnostics and monitoring has never been quenched. Questions, such as is breath acetone a biomarker of diabetes and how is the breath acetone related to the blood glucose (BG) level (the golden criterion currently used in clinic for diabetes diagnostic, monitoring, and management), remain to be answered. A majority of current research efforts in breath acetone measurements and its technology developments focus on addressing the first question. The effort to tackle the second question has begun recently. The earliest breath acetone measurement in clearly defined diabetic patients was reported more than 60 years ago. For more than a half-century, as reviewed in this paper, there have been more than 41 independent studies of breath acetone using various techniques and methods, and more than 3211 human subjects, including 1581 healthy people, 242 Type 1 diabetic patients, 384 Type 2 diabetic patients, 174 unspecified diabetic patients, and 830 non-diabetic patients or healthy subjects who are under various physiological conditions, have been used in the studies. The results of the breath acetone measurements collected in this review support that many conditions might cause changes to breath

Systematic Study of Separators in Air-Breathing Flat-Plate Microbial Fuel Cells—Part 2: Numerical Modeling

Directory of Open Access Journals (Sweden)

Sona Kazemi

2016-01-01

Full Text Available The separator plays a key role on the performance of passive air-breathing flat-plate MFCs (FPMFC as it isolates the anaerobic anode from the air-breathing cathode. The goal of the present work was to study the separator characteristics and its effect on the performance of passive air-breathing FPMFCs. This was performed partially through characterization of structure, properties, and performance correlations of eight separators presented in Part 1. Current work (Part 2 presents a numerical model developed based on the mixed potential theory to investigate the sensitivity of the electrode potentials and the power output to the separator characteristics. According to this numerical model, the decreased peak power results from an increase in the mass transfer coefficients of oxygen and ethanol, but mainly increasing mixed potentials at the anode by oxygen crossover. The model also indicates that the peak power is affected by the proton transport number of the separator, which affects the cathode pH. Anode pH, on the other hand, remains constant due to application of phosphate buffer solution as the electrolyte. Also according to this model, the peak power is not sensitive to the resistivity of the separator because of the overshadowing effect of the oxygen crossover.

Biocompatibility Research of a Novel pH Sensitive Ion Exchange Resin Microsphere.

Science.gov (United States)

Liu, Hongfei; Shi, Shuangshuang; Pan, Weisan; Sun, Changshan; Zou, Xiaomian; Fu, Min; Feng, Yingshu; Ding, Hui

2014-01-01

The main objective of this study was to investigate biocompatibility and provide in-vivo pharmacological and toxicological evidence for further investigation of the possibility of pH sensitive ion exchange resin microsphere for clinical utilizations. Acute toxicity study and general pharmacological studies were conducted on the pH sensitive ion exchange resin microsphere we prepared. The general pharmacological studies consist of the effects of the pH sensitive ion exchange resin microsphere on the nervous system of mice, the functional coordination of mice, the hypnosis of mice treated with nembutal at subliminal dose, the autonomic activities of tested mice, and the heart rate, blood pressure, ECG and breathing of the anesthetic cats. The LD50 of pH sensitive ion exchange resin microsphere after oral administration was more than 18.84 g·Kg(-1). Mice were orally administered with 16 mg·Kg(-1), 32 mg·Kg(-1) and 64 mg·Kg(-1) of pH sensitive ion exchange resin microsphere and there was no significant influence on mice nervous system, general behavior, function coordination, hypnotic effect treated with nembutal at subliminal dose and frequency of autonomic activities. Within the 90 min after 5 mg·Kg(-1), 10 mg·Kg(-1), 20 mg·Kg(-1) pH sensitive ion exchange resin microsphere was injected to cat duodenum, the heart rate, blood pressure, breathing and ECG of the cats didn't make significant changes in each experimental group compared with the control group. The desirable pharmacological and toxicological behaviors of the pH sensitive ion exchange resin microsphere exhibited that it has safe biocompatibility and is possible for clinical use.

What Causes Bad Breath?

Science.gov (United States)

... Videos for Educators Search English Español What Causes Bad Breath? KidsHealth / For Teens / What Causes Bad Breath? Print en español ¿Qué es lo que provoca el mal aliento? Bad breath, or halitosis , can be a major problem, ...

Air breathing and aquatic gas exchange during hypoxia in armoured catfish.

Science.gov (United States)

Scott, Graham R; Matey, Victoria; Mendoza, Julie-Anne; Gilmour, Kathleen M; Perry, Steve F; Almeida-Val, Vera M F; Val, Adalberto L

2017-01-01

Air breathing in fish is commonly believed to have arisen as an adaptation to aquatic hypoxia. The effectiveness of air breathing for tissue O 2 supply depends on the ability to avoid O 2 loss as oxygenated blood from the air-breathing organ passes through the gills. Here, we evaluated whether the armoured catfish (Hypostomus aff. pyreneusi)-a facultative air breather-can avoid branchial O 2 loss while air breathing in aquatic hypoxia, and we measured various other respiratory and metabolic traits important for O 2 supply and utilization. Fish were instrumented with opercular catheters to measure the O 2 tension (PO 2 ) of expired water, and air breathing and aquatic respiration were measured during progressive stepwise hypoxia in the water. Armoured catfish exhibited relatively low rates of O 2 consumption and gill ventilation, and gill ventilation increased in hypoxia due primarily to increases in ventilatory stroke volume. Armoured catfish began air breathing at a water PO 2 of 2.5 kPa, and both air-breathing frequency and hypoxia tolerance (as reflected by PO 2 at loss of equilibrium, LOE) was greater in individuals with a larger body mass. Branchial O 2 loss, as reflected by higher PO 2 in expired than in inspired water, was observed in a minority (4/11) of individuals as water PO 2 approached that at LOE. Armoured catfish also exhibited a gill morphology characterized by short filaments bearing short fused lamellae, large interlamellar cell masses, low surface area, and a thick epithelium that increased water-to-blood diffusion distance. Armoured catfish had a relatively low blood-O 2 binding affinity when sampled in normoxia (P 50 of 3.1 kPa at pH 7.4), but were able to rapidly increase binding affinity during progressive hypoxia exposure (to a P 50 of 1.8 kPa). Armoured catfish also had low activities of several metabolic enzymes in white muscle, liver, and brain. Therefore, low rates of metabolism and gill ventilation, and a reduction in branchial gas

Effect of airway acidosis and alkalosis on airway vascular smooth muscle responsiveness to albuterol.

Science.gov (United States)

Cancado, Jose E; Mendes, Eliana S; Arana, Johana; Horvath, Gabor; Monzon, Maria E; Salathe, Matthias; Wanner, Adam

2015-04-02

In vitro and animal experiments have shown that the transport and signaling of β2-adrenergic agonists are pH-sensitive. Inhaled albuterol, a hydrophilic β2-adrenergic agonist, is widely used for the treatment of obstructive airway diseases. Acute exacerbations of obstructive airway diseases can be associated with changes in ventilation leading to either respiratory acidosis or alkalosis thereby affecting albuterol responsiveness in the airway. The purpose of this study was to determine if airway pH has an effect on albuterol-induced vasodilation in the airway. Ten healthy volunteers performed the following respiratory maneuvers: quiet breathing, hypocapnic hyperventilation, hypercapnic hyperventilation, and eucapnic hyperventilation (to dissociate the effect of pH from the effect of ventilation). During these breathing maneuvers, exhaled breath condensate (EBC) pH and airway blood flow response to inhaled albuterol (ΔQ̇aw) were assessed. Mean ± SE EBC pH (units) and ΔQ̇aw (μl.min(-1).mL(-1)) were 6.4 ± 0.1 and 16.8 ± 1.9 during quiet breathing, 6.3 ± 0.1 and 14.5 ± 2.4 during eucapnic hyperventilation, 6.6 ± 0.2 and -0.2 ± 1.8 during hypocapnic hyperventilation (p = 0.02 and <0.01 vs. quiet breathing), and 5.9 ± 0.1 and 2.0 ± 1.5 during hypercapnic hyperventilation (p = 0.02 and <0.02 vs quiet breathing). Albuterol responsiveness in the airway as assessed by ΔQ̇aw is pH sensitive. The breathing maneuver associated with decreased and increased EBC pH both resulted in a decreased responsiveness independent of the level of ventilation. These findings suggest an attenuated response to hydrophilic β2-adrenergic agonists during airway disease exacerbations associated with changes in pH. Registered at clinicaltrials.gov: NCT01216748 .

UNDERWATER STROKE KINEMATICS DURING BREATHING AND BREATH-HOLDING FRONT CRAWL SWIMMING

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Nickos Vezos

2007-03-01

Full Text Available The aim of the present study was to determine the effects of breathing on the three - dimensional underwater stroke kinematics of front crawl swimming. Ten female competitive freestyle swimmers participated in the study. Each subject swam a number of front crawl trials of 25 m at a constant speed under breathing and breath-holding conditions. The underwater motion of each subject's right arm was filmed using two S-VHS cameras, operating at 60 Hz, which were positioned behind two underwater viewing windows. The spatial coordinates of selected points were calculated using the DLT procedure with 30 control points and after the digital filtering of the raw data with a cut-off frequency of 6 Hz, the hand's linear displacements and velocities were calculated. The results revealed that breathing caused significantly increases in the stroke duration (t9 = 2.764; p < 0.05, the backward hand displacement relative to the water (t9 = 2.471; p<0.05 and the lateral displacement of the hand in the X - axis during the downsweep (t9 = 2.638; p < 0.05. On the contrary, the peak backward hand velocity during the insweep (t9 = 2.368; p < 0.05 and the displacement of the hand during the push phase (t9 = -2.297; p < 0.05 were greatly reduced when breathing was involved. From the above, it was concluded that breathing action in front crawl swimming caused significant modifications in both the basic stroke parameters and the overall motor pattern were, possibly due to body roll during breathing

Breath in the technoscientific imaginary

OpenAIRE

Rose, Arthur

2016-01-01

Breath has a realist function in most artistic media. It serves to remind the reader, the viewer or the spectator of the exigencies of the body. In science fiction (SF) literature and films, breath is often a plot device for human encounters with otherness, either with alien peoples, who may not breathe oxygen, or environments, where there may not be oxygen to breathe. But while there is a technoscientific quality to breath in SF, especially in its attention to physiological systems, concentr...

THE COLOR GLASS CONDENSATE: A SUMMARY OF KEY IDEAS AND RECENT DEVELOPMENTS.

Energy Technology Data Exchange (ETDEWEB)

VENUGOPALAN,R.

2004-03-28

We summarize the theory and phenomenology of the Color Glass Condensate reviewed previously by E. Iancu and the author in hep-ph/0303204. In addition, we discuss some of the subsequent developments in the past year both in theory and in phenomenological applications.

Hypercarbic cardiorespiratory reflexes in the facultative air-breathing fish jeju (Hoplerythrinus unitaeniatus): the role of branchial CO2 chemoreceptors.

Science.gov (United States)

de Lima Boijink, Cheila; Florindo, Luiz Henrique; Leite, Cleo A Costa; Kalinin, Ana Lúcia; Milsom, William K; Rantin, Francisco Tadeu

2010-08-15

The aim of the present study was to determine the roles that externally versus internally oriented CO(2)/H(+)-sensitive chemoreceptors might play in promoting cardiorespiratory responses to environmental hypercarbia in the air-breathing fish, Hoplerythrinus unitaeniatus (jeju). Fish were exposed to graded hypercarbia (1, 2.5, 5, 10 and 20% CO(2)) and also to graded levels of environmental acidosis (pH approximately 7.0, 6.0, 5.8, 5.6, 5.3 and 4.7) equal to the pH levels of the hypercarbic water to distinguish the relative roles of CO(2) versus H(+). We also injected boluses of CO(2)-equilibrated solutions (5, 10 and 20% CO(2)) and acid solutions equilibrated to the same pH as the CO(2) boluses into the caudal vein (internal) and buccal cavity (external) to distinguish between internal and external stimuli. The putative location of the chemoreceptors was determined by bilateral denervation of branches of cranial nerves IX (glossopharyngeal) and X (vagus) to the gills. The data indicate that the chemoreceptors eliciting bradycardia, hypertension and gill ventilatory responses (increased frequency and amplitude) to hypercarbia are exclusively branchial, externally oriented and respond specifically to changes in CO(2) and not H(+). Those involved in producing the cardiovascular responses appeared to be distributed across all gill arches while those involved in the gill ventilatory responses were located primarily on the first gill arch. Higher levels of aquatic CO(2) depressed gill ventilation and stimulated air breathing. The chemoreceptors involved in producing air breathing in response to hypercarbia also appeared to be branchial, distributed across all gill arches and responded specifically to changes in aquatic CO(2). This would suggest that chemoreceptor groups with different orientations (blood versus water) are involved in eliciting air-breathing responses to hypercarbia in jeju.

An efficient mathematical model for air-breathing PEM fuel cells

International Nuclear Information System (INIS)

Ismail, M.S.; Ingham, D.B.; Hughes, K.J.; Ma, L.; Pourkashanian, M.

2014-01-01

Graphical abstract: The effects of the ambient humidity on the performance of air-breathing PEM fuel cells become more pronounced as the ambient temperature increases. The polarisation curves have been generated using the in-house developed MATLAB® application, Polarisation Curve Generator, which is available in the supplementary data. - Highlights: • An efficient mathematical model has been developed for an air-breathing PEM fuel cell. • The fuel cell performance is significantly over-predicted if the Joule and entropic heats are neglected. • The fuel cell performance is highly sensitive to the state of water at the thermodynamic equilibrium. • The cell potential dictates the favourable ambient conditions for the fuel cell. - Abstract: A simple and efficient mathematical model for air-breathing proton exchange membrane (PEM) fuel cells has been built. One of the major objectives of this study is to investigate the effects of the Joule and entropic heat sources, which are often neglected, on the performance of air-breathing PEM fuel cells. It is found that the fuel cell performance is significantly over-predicted if one or both of these heat sources is not incorporated into the model. Also, it is found that the performance of the fuel cell is highly sensitive to the state of the water at the thermodynamic equilibrium magnitude as both the entropic heat and the Nernst potential considerably increase if water is assumed to be produced in liquid form rather than in vapour form. Further, the heat of condensation is shown to be small and therefore, under single-phase modelling, has a negligible effect on the performance of the fuel cell. Finally, the favourable ambient conditions depend on the operating cell potential. At intermediate cell potentials, a mild ambient temperature and low humidity are favoured to maintain high membrane conductivity and mitigate water flooding. At low cell potentials, low ambient temperature and high humidity are favoured to

Laboratory Evaporation Testing Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

Energy Technology Data Exchange (ETDEWEB)

Adamson, Duane J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, Charles A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, William R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2014-01-01

(chloride, fluoride, sulfur), will have high ammonia, and will contain carryover particulates of glass-former chemicals. These species have potential to cause corrosion of tanks and equipment, precipitation of solids, release of ammonia gas vapors, and scale in the tank farm evaporator. Routing this stream to the tank farms does not permanently divert it from recycling into the WTP, only temporarily stores it prior to reprocessing. Testing is normally performed to demonstrate acceptable conditions and limits for these compounds in wastes sent to the tank farms. The primary parameter of this phase of the test program was measuring the formation of solids during evaporation in order to assess the compatibility of the stream with the evaporator and transfer and storage equipment. The origin of this LAW Off-Gas Condensate stream will be the liquids from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW facility melter offgas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover. The soluble components are expected to be mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet, and, thus, the composition will not be available until the WTP begins operation, but a simulant has been produced based on models, calculations, and comparison with pilot-scale tests. This report discusses results of evaporation testing of the simulant. Two conditions were tested, one with the simulant at near neutral pH, and a second at alkaline pH. The neutral pH test is comparable to the conditions in the Hanford Effluent Treatment Facility (ETF) evaporator, although that evaporator operates at near atmospheric pressure and tests were done under vacuum. For the alkaline test, the target pH was based on the tank farm corrosion control program requirements, and the test protocol and equipment was comparable to that

Laboratory Evaporation Testing Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

International Nuclear Information System (INIS)

Adamson, Duane J.; Nash, Charles A.; McCabe, Daniel J.; Crawford, Charles L.; Wilmarth, William R.

2014-01-01

(chloride, fluoride, sulfur), will have high ammonia, and will contain carryover particulates of glass-former chemicals. These species have potential to cause corrosion of tanks and equipment, precipitation of solids, release of ammonia gas vapors, and scale in the tank farm evaporator. Routing this stream to the tank farms does not permanently divert it from recycling into the WTP, only temporarily stores it prior to reprocessing. Testing is normally performed to demonstrate acceptable conditions and limits for these compounds in wastes sent to the tank farms. The primary parameter of this phase of the test program was measuring the formation of solids during evaporation in order to assess the compatibility of the stream with the evaporator and transfer and storage equipment. The origin of this LAW Off-Gas Condensate stream will be the liquids from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW facility melter offgas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover. The soluble components are expected to be mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet, and, thus, the composition will not be available until the WTP begins operation, but a simulant has been produced based on models, calculations, and comparison with pilot-scale tests. This report discusses results of evaporation testing of the simulant. Two conditions were tested, one with the simulant at near neutral pH, and a second at alkaline pH. The neutral pH test is comparable to the conditions in the Hanford Effluent Treatment Facility (ETF) evaporator, although that evaporator operates at near atmospheric pressure and tests were done under vacuum. For the alkaline test, the target pH was based on the tank farm corrosion control program requirements, and the test protocol and equipment was comparable to that

CONDENSATION OF WATER VAPOR IN A VERTICAL TUBE CONDENSER

Directory of Open Access Journals (Sweden)

Jan Havlík

2015-10-01

Full Text Available This paper presents an analysis of heat transfer in the process of condensation of water vapor in a vertical shell-and-tube condenser. We analyze the use of the Nusselt model for calculating the condensation heat transfer coefficient (HTC inside a vertical tube and the Kern, Bell-Delaware and Stream-flow analysis methods for calculating the shell-side HTC from tubes to cooling water. These methods are experimentally verified for a specific condenser of waste process vapor containing air. The operating conditions of the condenser may be different from the assumptions adopted in the basic Nusselt theory. Modifications to the Nusselt condensation model are theoretically analyzed.

Breath in the technoscientific imaginary.

Science.gov (United States)

Rose, Arthur

2016-12-01

Breath has a realist function in most artistic media. It serves to remind the reader, the viewer or the spectator of the exigencies of the body. In science fiction (SF) literature and films, breath is often a plot device for human encounters with otherness, either with alien peoples, who may not breathe oxygen, or environments, where there may not be oxygen to breathe. But while there is a technoscientific quality to breath in SF, especially in its attention to physiological systems, concentrating on the technoscientific threatens to occlude other, more affective aspects raised by the literature. In order to supplement the tendency to read SF as a succession of technoscientific accounts of bodily experience, this paper recalls how SF texts draw attention to the affective, non-scientific qualities of breath, both as a metonym for life and as a metaphor for anticipation. Through an engagement with diverse examples from SF literature and films, this article considers the tension between technoscientific and affective responses to breath in order to demonstrate breath's co-determinacy in SF's blending of scientific and artistic discourses. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Steam condenser

International Nuclear Information System (INIS)

Masuda, Fujio

1980-01-01

Purpose: To enable safe steam condensation by providing steam condensation blades at the end of a pipe. Constitution: When high temperature high pressure steam flows into a vent pipe having an opening under water in a pool or an exhaust pipe or the like for a main steam eacape safety valve, non-condensable gas filled beforehand in the steam exhaust pipe is compressed, and discharged into the water in the pool. The non-condensable gas thus discharged from the steam exhaust pipe is introduced into the interior of the hollow steam condensing blades, is then suitably expanded, and thereafter exhausted from a number of exhaust holes into the water in the pool. In this manner, the non-condensable gas thus discharged is not directly introduced into the water in the pool, but is suitable expanded in the space of the steam condensing blades to suppress extreme over-compression and over-expansion of the gas so as to prevent unstable pressure vibration. (Yoshihara, H.)

Chemical sensors for breath gas analysis: the latest developments at the Breath Analysis Summit 2013.

Science.gov (United States)

Tisch, Ulrike; Haick, Hossam

2014-06-01

Profiling the body chemistry by means of volatile organic compounds (VOCs) in the breath opens exciting new avenues in medical diagnostics. Gas sensors could provide ideal platforms for realizing portable, hand-held breath testing devices in the near future. This review summarizes the latest developments and applications in the field of chemical sensors for diagnostic breath testing that were presented at the Breath Analysis Summit 2013 in Wallerfangen, Germany. Considerable progress has been made towards clinically applicable breath testing devices, especially by utilizing chemo-sensitive nanomaterials. Examples of several specialized breath testing applications are presented that are either based on stand-alone nanomaterial-based sensors being highly sensitive and specific to individual breath compounds over others, or on combinations of several highly specific sensors, or on experimental nanomaterial-based sensors arrays. Other interesting approaches include the adaption of a commercially available MOx-based sensor array to indirect breath testing applications, using a sample pre-concentration method, and the development of compact integrated GC-sensor systems. The recent trend towards device integration has led to the development of fully integrated prototypes of point-of-care devices. We describe and compare the performance of several prototypes that are based on different sensing technologies and evaluate their potential as low-cost and readily available next-generation medical devices.

The use of active breathing control (ABC) to reduce margin for breathing motion

International Nuclear Information System (INIS)

Wong, John W.; Sharpe, Michael B.; Jaffray, David A.; Kini, Vijay R.; Robertson, John M.; Stromberg, Jannifer S.; Martinez, Alavro A.

1999-01-01

Purpose: For tumors in the thorax and abdomen, reducing the treatment margin for organ motion due to breathing reduces the volume of normal tissues that will be irradiated. A higher dose can be delivered to the target, provided that the risk of marginal misses is not increased. To ensure safe margin reduction, we investigated the feasibility of using active breathing control (ABC) to temporarily immobilize the patient's breathing. Treatment planning and delivery can then be performed at identical ABC conditions with minimal margin for breathing motion. Methods and Materials: An ABC apparatus is constructed consisting of 2 pairs of flow monitor and scissor valve, 1 each to control the inspiration and expiration paths to the patient. The patient breathes through a mouth-piece connected to the ABC apparatus. The respiratory signal is processed continuously, using a personal computer that displays the changing lung volume in real-time. After the patient's breathing pattern becomes stable, the operator activates ABC at a preselected phase in the breathing cycle. Both valves are then closed to immobilize breathing motion. Breathing motion of 12 patients were held with ABC to examine their acceptance of the procedure. The feasibility of applying ABC for treatment was tested in 5 patients by acquiring volumetric scans with a spiral computed tomography (CT) scanner during active breath-hold. Two patients had Hodgkin's disease, 2 had metastatic liver cancer, and 1 had lung cancer. Two intrafraction ABC scans were acquired at the same respiratory phase near the end of normal or deep inspiration. An additional ABC scan near the end of normal expiration was acquired for 2 patients. The ABC scans were also repeated 1 week later for a Hodgkin's patient. In 1 liver patient, ABC scans were acquired at 7 different phases of the breathing cycle to facilitate examination of the liver motion associated with ventilation. Contours of the lungs and livers were outlined when applicable

Preventing freezing of condensate inside tubes of air cooled condenser

International Nuclear Information System (INIS)

Joo, Jeong A; Hwang, In Hwan; Lee, Dong Hwan; Cho, Young Il

2012-01-01

An air cooled condenser is a device that is used for converting steam into condensate by using ambient air. The air cooled condenser is prone to suffer from a serious explosion when the condensate inside the tubes of a heat exchanger is frozen; in particular, tubes can break during winter. This is primarily due to the structural problem of the tube outlet of an existing conventional air cooled condenser system, which causes the backflow of residual steam and noncondensable gases. To solve the backflow problem in such condensers, such a system was simulated and a new system was designed and evaluated in this study. The experimental results using the simulated condenser showed the occurrence of freezing because of the backflow inside the tube. On the other hand, no backflow and freezing occurred in the advanced new condenser, and efficient heat exchange occurred

Condensate subcooling near tube exit during horizontal in-tube condensation

International Nuclear Information System (INIS)

Hashizume, K.; Abe, N.; Ozeki, T.

1992-01-01

In-tube condensation is encountered in various applications for heat exchangers, such as domestic air-conditioning equipment, industrial air-cooled condensers, and moisture separator reheaters (MSRs) for nuclear power pants. Numerous research work has been conducted to predict the condensation heat transfer coefficient, and we have now enough information for thermal design of heat exchangers with horizontal in-tube condensation. Most of the research is analytical and/or experimental work in the annular or stratified flow regime, or experimental work on bulk condensation, i.e., from saturated vapor to complete condensation. On the other hand, there exist few data about the heat transfer phenomena in the very lower-quality region near the tube exit. The purpose of this paper is to clarify the condensation heat transfer phenomena near the tube exit experimentally and analytically, and to predict the degree of condensate subcooling

Effect of oxygenation on breath-by-breath response of the genioglossus muscle during occlusion.

Science.gov (United States)

Gauda, E B; Carroll, J L; McColley, S; Smith, P L

1991-10-01

We investigated the effect of different levels of O2 tension (hypoxia, normoxia, and hyperoxia) on the breath-by-breath onset and peak electromyographic (EMG) activity of the genioglossus (GG) muscle during a five-breath end-expiratory tracheal occlusion of 20- to 30-s duration. GG and diaphragmatic (DIA) EMG activity were measured with needle electrodes in eight anesthetized tracheotomized adult cats. In response to occlusion, the increase in the number of animals with GG EMG activity was different during hypoxia, normoxia, and hyperoxia (P = 0.003, Friedman). During hypoxia, eight of eight of the animals had GG EMG activity by the third occluded effort. In contrast, during normoxia, only four of eight and, during hyperoxia, only three of eight animals had GG EMG activity throughout the entire five-breath occlusion. Similarly, at release of the occlusion, more animals had persistent GG EMG activity on the postocclusion breaths during hypoxia than during normoxia or hyperoxia. Breath-by-breath augmentation of peak amplitude of the GG and DIA EMGs on each occluded effort was accentuated during hypoxia (P less than 0.01) and abolished during hyperoxia (P = 0.10). These results suggest that hypoxemia is a major determinant of the rapidity of onset, magnitude, and sustained activity of upper airway muscles during airway occlusion.

Determination of breath acetone in 149 type 2 diabetic patients using a ringdown breath-acetone analyzer.

Science.gov (United States)

Sun, Meixiu; Chen, Zhuying; Gong, Zhiyong; Zhao, Xiaomeng; Jiang, Chenyu; Yuan, Yuan; Wang, Zhennang; Li, Yingxin; Wang, Chuji

2015-02-01

Over 90% of diabetic patients have Type 2 diabetes. Although an elevated mean breath acetone concentration has been found to exist in Type 1 diabetes (T1D), information on breath acetone in Type 2 diabetes (T2D) has yet to be obtained. In this study, we first used gas chromatography-mass spectrometry (GC-MS) to validate a ringdown breath-acetone analyzer based on the cavity-ringdown-spectroscopy technique, through comparing breath acetone concentrations in the range 0.5-2.5 ppm measured using both methods. The linear fitting of R = 0.99 suggests that the acetone concentrations obtained using both methods are consistent with a largest standard deviation of ±0.4 ppm in the lowest concentration of the range. Next, 620 breath samples from 149 T2D patients and 42 healthy subjects were collected and tested using the breath analyzer. Four breath samples were taken from each subject under each of four different conditions: fasting, 2 h post-breakfast, 2 h post-lunch, and 2 h post-dinner. Simultaneous blood glucose levels were also measured using a standard diabetic-management blood-glucose meter. For the 149 T2D subjects, their exhaled breath acetone concentrations ranged from 0.1 to 19.8 ppm; four different ranges of breath acetone concentration, 0.1-19.8, 0.1-7.1, 0.1-6.3, and 0.1-9.5 ppm, were obtained for the subjects under the four different conditions, respectively. For the 42 healthy subjects, their breath acetone concentration ranged from 0.1 to 2.6 ppm; four different ranges of breath acetone concentration, 0.3-2.6, 0.1-2.6, 0.1-1.7, and 0.3-1.6 ppm, were obtained for the four different conditions. The mean breath acetone concentration of the 149 T2D subjects was determined to be 1.5 ± 1.5 ppm, which was 1.5 times that of 1.0 ± 0.6 ppm for the 42 healthy subjects. No correlation was found between the breath acetone concentration and the blood glucose level of the T2D subjects and the healthy volunteers. This study using a relatively large number of

Breath Analysis Using Laser Spectroscopic Techniques: Breath Biomarkers, Spectral Fingerprints, and Detection Limits

Directory of Open Access Journals (Sweden)

Peeyush Sahay

2009-10-01

Full Text Available Breath analysis, a promising new field of medicine and medical instrumentation, potentially offers noninvasive, real-time, and point-of-care (POC disease diagnostics and metabolic status monitoring. Numerous breath biomarkers have been detected and quantified so far by using the GC-MS technique. Recent advances in laser spectroscopic techniques and laser sources have driven breath analysis to new heights, moving from laboratory research to commercial reality. Laser spectroscopic detection techniques not only have high-sensitivity and high-selectivity, as equivalently offered by the MS-based techniques, but also have the advantageous features of near real-time response, low instrument costs, and POC function. Of the approximately 35 established breath biomarkers, such as acetone, ammonia, carbon dioxide, ethane, methane, and nitric oxide, 14 species in exhaled human breath have been analyzed by high-sensitivity laser spectroscopic techniques, namely, tunable diode laser absorption spectroscopy (TDLAS, cavity ringdown spectroscopy (CRDS, integrated cavity output spectroscopy (ICOS, cavity enhanced absorption spectroscopy (CEAS, cavity leak-out spectroscopy (CALOS, photoacoustic spectroscopy (PAS, quartz-enhanced photoacoustic spectroscopy (QEPAS, and optical frequency comb cavity-enhanced absorption spectroscopy (OFC-CEAS. Spectral fingerprints of the measured biomarkers span from the UV to the mid-IR spectral regions and the detection limits achieved by the laser techniques range from parts per million to parts per billion levels. Sensors using the laser spectroscopic techniques for a few breath biomarkers, e.g., carbon dioxide, nitric oxide, etc. are commercially available. This review presents an update on the latest developments in laser-based breath analysis.

Text condensation in consecutive interpreting - summary of a Ph.d.-dissertation

DEFF Research Database (Denmark)

Dam, Helle Vrønning

1996-01-01

Artiklen er et resumé af en Ph.d.-afhandling med titlen 'Tekstkondensering i foredragstolkning', som blev indleveret ved Det Erhvervssproglige Fakultet, Handelshøjskolen i Århus, i oktober 1995. I artiklen skitseres den valgte interdisciplinære tilgang til det fænomen, der undersøges i afhandling...

Assessment of reproducibility and stability of different breath-hold maneuvres by dynamic MRI: comparison between healthy adults and patients with pulmonary hypertension

Energy Technology Data Exchange (ETDEWEB)

Plathow, Christian [German Cancer Research Center Heidelberg, Department of Radiology, Heidelberg (Germany); Eberhard-Karls-University Tuebingen, Department of Diagnostic Radiology, Tuebingen (Germany); Ley, Sebastian; Zaporozhan, Julia; Puderbach, Michael; Eichinger, Monika; Zuna, Ivan; Kauczor, Hans-Ulrich [German Cancer Research Center Heidelberg, Department of Radiology, Heidelberg (Germany); Schoebinger, Max; Meinzer, Hans-Peter [German Cancer Research Center Heidelberg, Department of Medical and Biological Informatics, Heidelberg (Germany); Gruenig, Ekkehard [University of Heidelberg, Department of Internal Medicine III, Heidelberg (Germany)

2006-01-01

To assess the stability and reproducibility of different breath-hold levels in healthy volunteers and patients using dynamic MRI (dMRI). In ten healthy volunteers and ten patients with pulmonary hypertension (PH) and normal lung function craniocaudal intrathoracic distances (CCD) were measured during inspiratory and expiratory breath-hold (15 s) (in healthy volunteers additionally at a self-chosen mid-inspiratory breath-hold) using dMRI (trueFISP, three images/s). To evaluate stability and intraobserver reproducibility of the different breath-hold levels, CCDs, time-distance curves, confidence intervals (CIs), Mann-Witney U test and regression equations were calculated. In healthy volunteers there was a substantial decrease of the CCD during the inspiratory breath-hold in contrast to the expiratory breath-hold. The CI at inspiration was 2.84{+-}1.28 in the right and 2.1{+-}0.68 in the left hemithorax. At expiration the CI was 2.54{+-}1.18 and 2.8{+-}1.48. Patients were significantly less able to hold their breath at inspiration than controls (P<0.05). In patients CI was 4.53{+-}4.06 and 3.46{+-}2.21 at inspiration and 4.45{+-}4.23 and 4.76{+-}3.73 at expiration. Intraobserver variability showed no significant differences either in patients or in healthy subjects. Reproducibility was significantly lower at a self-chosen breath-hold level of the healthy volunteers. DMRI is able to differentiate stability and reproducibility of different breath-hold levels. Expiratory breath-hold proved to be more stable than inspiratory breath-hold in healthy volunteers and patients. (orig.)

From Feshbach-resonance managed Bose-Einstein condensates to anisotropic universes: Applications of the Ermakov-Pinney equation with time-dependent nonlinearity

International Nuclear Information System (INIS)

Herring, G.; Kevrekidis, P.G.; Williams, F.; Christodoulakis, T.; Frantzeskakis, D.J.

2008-01-01

In this work we revisit the topic of two-dimensional Bose-Einstein condensates under the influence of time-dependent magnetic confinement and time-dependent scattering length. A moment approach reduces the examination of moments of the wavefunction (in particular, of its width) to an Ermakov-Pinney (EP) ordinary differential equation (ODE). We use the well-known structure of the solutions of this nonlinear ODE to 'engineer' trapping and interatomic interaction conditions that lead to condensates dispersing, breathing or even collapsing. The advantage of the approach is that it is fully tractable analytically, in excellent agreement with our numerical observations. As an aside, we also discuss how similar time-dependent EP equations may arise in the description of anisotropic scalar field cosmologies

From Feshbach-resonance managed Bose-Einstein condensates to anisotropic universes: Applications of the Ermakov-Pinney equation with time-dependent nonlinearity

International Nuclear Information System (INIS)

Herring, G.; Kevrekidis, P.G.; Williams, F.; Christodoulakis, T.; Frantzeskakis, D.J.

2007-01-01

In this work we revisit the topic of two-dimensional Bose-Einstein condensates under the influence of time-dependent magnetic confinement and time-dependent scattering length. A moment approach reduces the examination of moments of the wavefunction (in particular, of its width) to an Ermakov-Pinney (EP) ordinary differential equation (ODE). We use the well-known structure of the solutions of this nonlinear ODE to 'engineer' trapping and interatomic interaction conditions that lead to condensates dispersing, breathing or even collapsing. The advantage of the approach is that it is fully tractable analytically, in excellent agreement with our numerical observations. As an aside, we also discuss how similar time-dependent EP equations may arise in the description of anisotropic scalar field cosmologies

Body composition variation following diaphragmatic breathing ...

African Journals Online (AJOL)

Body composition variation following diaphragmatic breathing. ... effect of commonly prescribed diaphragmatic breathing training on the body composition ... a non-exercising control (NE) group (n = 22) or diaphragmatic breathing (DB) group.

Thoracic radiotherapy and breath control: current prospects

International Nuclear Information System (INIS)

Reboul, F.; Mineur, L.; Paoli, J.B.; Bodez, V.; Oozeer, R.; Garcia, R.

2002-01-01

Three-dimensional conformal radiotherapy (3D CRT) is adversely affected by setup error and organ motion. In thoracic 3D CRT, breathing accounts for most of intra-fraction movements, thus impairing treatment quality. Breath control clearly exhibits dosimetric improvement compared to free breathing, leading to various techniques for gated treatments. We review benefits of different breath control methods -i.e. breath-holding or beam gating, with spirometric, isometric or X-ray respiration sensor- and argument the choice of expiration versus inspiration, with consideration to dosimetric concerns. All steps of 3D-CRT can be improved with breath control. Contouring of organs at risk (OAR) and target are easier and more accurate on breath controlled CT-scans. Inter- and intra-fraction target immobilisation allows smaller margins with better coverage. Lung outcome predictors (NTCP, Mean Dose, LV20, LV30) are improved with breath-control. In addition, inspiration breath control facilitates beam arrangement since it widens the distance between OAR and target, and leaves less lung normal tissue within the high dose region. Last, lung density, as of CT scan, is more accurate, improving dosimetry. Our institutions choice is to use spirometry driven, patient controlled high-inspiration breath-hold; this technique gives excellent immobilization results, with high reproducibility, yet it is easy to implement and costs little extra treatment time. Breath control, whatever technique is employed, proves superior to free breathing treatment when using 3D-CRT. Breath control should then be used whenever possible, and is probably mandatory for IMRT. (authors)

Water Condensation

DEFF Research Database (Denmark)

Jensen, Kasper Risgaard; Fojan, Peter; Jensen, Rasmus Lund

2014-01-01

The condensation of water is a phenomenon occurring in multiple situations in everyday life, e.g., when fog is formed or when dew forms on the grass or on windows. This means that this phenomenon plays an important role within the different fields of science including meteorology, building physics......, and chemistry. In this review we address condensation models and simulations with the main focus on heterogeneous condensation of water. The condensation process is, at first, described from a thermodynamic viewpoint where the nucleation step is described by the classical nucleation theory. Further, we address...

Text condensation in consecutive interpreting - summary of a Ph.d.-dissertation

OpenAIRE

Dam, Helle Vrønning

1996-01-01

Artiklen er et resumé af en Ph.d.-afhandling med titlen 'Tekstkondensering i foredragstolkning', som blev indleveret ved Det Erhvervssproglige Fakultet, Handelshøjskolen i Århus, i oktober 1995. I artiklen skitseres den valgte interdisciplinære tilgang til det fænomen, der undersøges i afhandlingen, ligesom de anvendte metoder og analysemodeller præsenteres.

SU-E-T-326: The Oxygen Saturation (SO2) and Breath-Holding Time Variation Applied Active Breathing Control (ABC)

Energy Technology Data Exchange (ETDEWEB)

Gong, G; Yin, Y [Shandong Cancer Hospital, Jinan, Shandong (China)

2014-06-01

Purpose: To study the oxygen saturation (SO2) and breath-holding time variation applied active breathing control (ABC) in radiotherapy of tumor. Methods: 24 volunteers were involved in our trials, and they all did breath-holding motion assisted by ELEKTA Active Breathing Coordinator 2.0 for 10 times respectively. And the patient monitor was used to observe the oxygen saturation (SO2) variation. The variation of SO2, and length of breath-holding time and the time for recovering to the initial value of SO2 were recorded and analyzed. Results: (1) The volunteers were divided into two groups according to the SO2 variation in breath-holding: A group, 14 cases whose SO2 reduction were more than 2% (initial value was 97% to 99%, while termination value was 91% to 96%); B group, 10 cases were less than 2% in breath-holding without inhaling oxygen. (2) The interfraction breath holding time varied from 8 to 20s for A group compared to the first breath-holding time, and for B group varied from 4 to 14s. (3) The breathing holding time of B group prolonged mean 8s, compared to A group. (4) The time for restoring to the initial value of SO2 was from 10s to 30s. And the breath-holding time shortened obviously for patients whose SO2 did not recover to normal. Conclusion: It is very obvious that the SO2 reduction in breath-holding associated with ABC for partial people. It is necessary to check the SO2 variation in breath training, and enough time should be given to recover SO2.

Assessment of reproducibility and stability of different breath-hold maneuvres by dynamic MRI: comparison between healthy adults and patients with pulmonary hypertension

International Nuclear Information System (INIS)

Plathow, Christian; Ley, Sebastian; Zaporozhan, Julia; Puderbach, Michael; Eichinger, Monika; Zuna, Ivan; Kauczor, Hans-Ulrich; Schoebinger, Max; Meinzer, Hans-Peter; Gruenig, Ekkehard

2006-01-01

To assess the stability and reproducibility of different breath-hold levels in healthy volunteers and patients using dynamic MRI (dMRI). In ten healthy volunteers and ten patients with pulmonary hypertension (PH) and normal lung function craniocaudal intrathoracic distances (CCD) were measured during inspiratory and expiratory breath-hold (15 s) (in healthy volunteers additionally at a self-chosen mid-inspiratory breath-hold) using dMRI (trueFISP, three images/s). To evaluate stability and intraobserver reproducibility of the different breath-hold levels, CCDs, time-distance curves, confidence intervals (CIs), Mann-Witney U test and regression equations were calculated. In healthy volunteers there was a substantial decrease of the CCD during the inspiratory breath-hold in contrast to the expiratory breath-hold. The CI at inspiration was 2.84±1.28 in the right and 2.1±0.68 in the left hemithorax. At expiration the CI was 2.54±1.18 and 2.8±1.48. Patients were significantly less able to hold their breath at inspiration than controls (P<0.05). In patients CI was 4.53±4.06 and 3.46±2.21 at inspiration and 4.45±4.23 and 4.76±3.73 at expiration. Intraobserver variability showed no significant differences either in patients or in healthy subjects. Reproducibility was significantly lower at a self-chosen breath-hold level of the healthy volunteers. DMRI is able to differentiate stability and reproducibility of different breath-hold levels. Expiratory breath-hold proved to be more stable than inspiratory breath-hold in healthy volunteers and patients. (orig.)

The relationship between fetal biophysical profile and cord blood PH

Directory of Open Access Journals (Sweden)

Valadan M

2009-02-01

Full Text Available "nBackground: The Biophysical Profile (BPP is a noninvasive test that predicts the presence or absence of fetal asphyxia and, ultimately, the risk of fetal death in the antenatal period. Intervention on the basis of an abnormal biophysical profile result has been reported to yield a significant reduction in prenatal mortality, and an association exists between biophysical profile scoring and a decreased cerebral palsy rate in a given population. The BPP evaluates five characteristics: fetal movement, tone, breathing, heart reactivity, and amniotic fluid (AF volume estimation. The purpose of study was to determine whether there are different degree of acidosis at which the biophysical activity (acute marker are affected. "nMethods: In a prospective study of 140 patients undergoing cesarean section before onset of labor, the fetal biophysical profile was performed 24h before the time of cesarean and was matched with cord arterial PH that was obtained from a cord segment (10-20cm that was double clamped after delivery of newborn. (using cord arterial PH less than 7.20 for the diagnosis of acidosis. "nResults: The fetal biophysical profile was found to have a significant relationship with umbilical blood PH. The sensitivity, specificity, positive predictive value, negative predictive value of fetal biophysical profile score were: 88.9%, 88.6%, 50%, 98.1%. "nConclusion: The first manifestations of fetal acidosis are nonreactive nonstress testing and fetal breathing loss; in advanced acidemia fetal movements and fetal tone are compromised. A protocol of antepartum fetal evaluation is suggested based upon the individual biophysical components rather than the score alone.

FMWC Radar for Breath Detection

DEFF Research Database (Denmark)

Suhr, Lau Frejstrup; Tafur Monroy, Idelfonso; Vegas Olmos, Juan José

We report on the experimental demonstration of an FMCW radar operating in the 25.7 - 26.6 GHz range with a repetition rate of 500 sweeps per second. The radar is able to track the breathing rate of an adult human from a distance of 1 meter. The experiments have utilized a 50 second recording window...... to accurately track the breathing rate. The radar utilizes a saw tooth modulation format and a low latency receiver. A breath tracking radar is useful both in medical scenarios, diagnosing disorders such as sleep apnea, and for home use where the user can monitor its health. Breathing is a central part of every...... radar chip which, through the use of a simple modulation scheme, is able to measure the breathing rate of an adult human from a distance. A high frequency output makes sure that the radar cannot penetrate solid obstacles which is a wanted feature in private homes where people therefore cannot measure...

46 CFR 197.456 - Breathing supply hoses.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing supply hoses. 197.456 Section 197.456 Shipping....456 Breathing supply hoses. (a) The diving supervisor shall insure that— (1) Each breathing supply....5 times its maximum working pressure; (2) Each breathing supply hose assembly, prior to being placed...

Visualizing Breath using Digital Holography

Science.gov (United States)

Hobson, P. R.; Reid, I. D.; Wilton, J. B.

2013-02-01

Artist Jayne Wilton and physicists Peter Hobson and Ivan Reid of Brunel University are collaborating at Brunel University on a project which aims to use a range of techniques to make visible the normally invisible dynamics of the breath and the verbal and non-verbal communication it facilitates. The breath is a source of a wide range of chemical, auditory and physical exchanges with the direct environment. Digital Holography is being investigated to enable a visually stimulating articulation of the physical trajectory of the breath as it leaves the mouth. Initial findings of this research are presented. Real time digital hologram replay allows the audience to move through holographs of breath-born particles.

Swimming in air-breathing fishes.

Science.gov (United States)

Lefevre, S; Domenici, P; McKenzie, D J

2014-03-01

Fishes with bimodal respiration differ in the extent of their reliance on air breathing to support aerobic metabolism, which is reflected in their lifestyles and ecologies. Many freshwater species undertake seasonal and reproductive migrations that presumably involve sustained aerobic exercise. In the six species studied to date, aerobic exercise in swim flumes stimulated air-breathing behaviour, and there is evidence that surfacing frequency and oxygen uptake from air show an exponential increase with increasing swimming speed. In some species, this was associated with an increase in the proportion of aerobic metabolism met by aerial respiration, while in others the proportion remained relatively constant. The ecological significance of anaerobic swimming activities, such as sprinting and fast-start manoeuvres during predator-prey interactions, has been little studied in air-breathing fishes. Some species practise air breathing during recovery itself, while others prefer to increase aquatic respiration, possibly to promote branchial ion exchange to restore acid-base balance, and to remain quiescent and avoid being visible to predators. Overall, the diversity of air-breathing fishes is reflected in their swimming physiology as well, and further research is needed to increase the understanding of the differences and the mechanisms through which air breathing is controlled and used during exercise. © 2014 The Fisheries Society of the British Isles.

Performance of evaporative condensers

Energy Technology Data Exchange (ETDEWEB)

Ettouney, Hisham M.; El-Dessouky, Hisham T.; Bouhamra, Walid; Al-Azmi, Bader

2001-07-01

Experimental investigation is conducted to study the performance of evaporative condensers/coolers. The analysis includes development of correlations for the external heat transfer coefficient and the system efficiency. The evaporative condenser includes two finned-tube heat exchangers. The system is designed to allow for operation of a single condenser, two condensers in parallel, and two condensers in series. The analysis is performed as a function of the water-to-air mass flow rate ratio (L/G) and the steam temperature. Also, comparison is made between the performance of the evaporative condenser and same device as an air-cooled condenser. Analysis of the collected data shows that the system efficiency increases at lower L/G ratios and higher steam temperatures. The system efficiency for various configurations for the evaporative condenser varies between 97% and 99%. Lower efficiencies are obtained for the air-cooled condenser, with values between 88% and 92%. The highest efficiency is found for the two condensers in series, followed by two condensers in parallel and then the single condenser. The parallel condenser configuration can handle a larger amount of inlet steam and can provide the required system efficiency and degree of subcooling. The correlation for the system efficiency gives a simple tool for preliminary system design. The correlation developed for the external heat transfer coefficient is found to be consistent with the available literature data. (Author)

Breath-Hold Diving.

Science.gov (United States)

Fitz-Clarke, John R

2018-03-25

Breath-hold diving is practiced by recreational divers, seafood divers, military divers, and competitive athletes. It involves highly integrated physiology and extreme responses. This article reviews human breath-hold diving physiology beginning with an historical overview followed by a summary of foundational research and a survey of some contemporary issues. Immersion and cardiovascular adjustments promote a blood shift into the heart and chest vasculature. Autonomic responses include diving bradycardia, peripheral vasoconstriction, and splenic contraction, which help conserve oxygen. Competitive divers use a technique of lung hyperinflation that raises initial volume and airway pressure to facilitate longer apnea times and greater depths. Gas compression at depth leads to sequential alveolar collapse. Airway pressure decreases with depth and becomes negative relative to ambient due to limited chest compliance at low lung volumes, raising the risk of pulmonary injury called "squeeze," characterized by postdive coughing, wheezing, and hemoptysis. Hypoxia and hypercapnia influence the terminal breakpoint beyond which voluntary apnea cannot be sustained. Ascent blackout due to hypoxia is a danger during long breath-holds, and has become common amongst high-level competitors who can suppress their urge to breathe. Decompression sickness due to nitrogen accumulation causing bubble formation can occur after multiple repetitive dives, or after single deep dives during depth record attempts. Humans experience responses similar to those seen in diving mammals, but to a lesser degree. The deepest sled-assisted breath-hold dive was to 214 m. Factors that might determine ultimate human depth capabilities are discussed. © 2018 American Physiological Society. Compr Physiol 8:585-630, 2018. Copyright © 2018 American Physiological Society. All rights reserved.

Condensation of steam

International Nuclear Information System (INIS)

Prisyazhniuk, V.A.

2002-01-01

An equation for nucleation kinetics in steam condensation has been derived, the equation taking into account the concurrent and independent functioning of two nucleation mechanisms: the homogeneous one and the heterogeneous one. The equation is a most general-purpose one and includes all the previously known condensation models as special cases. It is shown how the equation can be used in analyzing the process of steam condensation in the condenser of an industrial steam-turbine plant, and in working out new ways of raising the efficiency of the condenser, as well as of the steam-turbine plant as a whole. (orig.)

Modelling of condensation phenomena

International Nuclear Information System (INIS)

Jeong, Jae Jun; Chang, Won Pyo

1996-07-01

Condensation occurs when vapor is cooled sufficiently below the saturation temperature to induce the nucleation of droplets. Such nucleation may occur homogeneously within the vapor or heterogeneously on entrained particular matter. Heterogeneous nucleation may occur on the walls of the system, where the temperature is below the saturation temperature. There are two forms of heterogeneous condensation, drop-wise and film-wise. Another form of condensation occurs when vapor directly contacts to subcooled liquid. In nuclear power plant systems, all forms of condensation may occur during normal operation or accident conditions. In this work the modelling of condensation is surveyed, including the Nusselts' laminar film condensation theory in 1916, Rohsenow's turbulent film condensation model in 1950s, and Chen's models in 1987. Major attention is paid on the film condensation models among various research results because of its importance in engineering applications. It is found that theory, experiment, and empirical correlations for film condensation are well established, but research for drop-wise and direct-contact condensation are not sufficient yet. Condensation models in the best-estimate system codes such as RELAP5/MOD3 and CATHARE2 are also investigated. 3 tabs., 11 figs., 36 refs. (Author)

Improved condenser design and condenser-fan operation for air-cooled chillers

International Nuclear Information System (INIS)

Yu, F.W.; Chan, K.T.

2006-01-01

Air-cooled chillers traditionally operate under head pressure control via staging constant-speed condenser fans. This causes a significant drop in their coefficient of performance (COP) at part load or low outdoor temperatures. This paper describes how the COP of these chillers can be improved by a new condenser design, using evaporative pre-coolers and variable-speed fans. A thermodynamic model for an air-cooled screw-chiller was developed, within which the condenser component considers empirical equations showing the effectiveness of an evaporative pre-cooler in lowering the outdoor temperature in the heat-rejection process. The condenser component also contains an algorithm to determine the number and speed of the condenser fans staged at any given set point of condensing temperature. It is found that the chiller's COP can be maximized by adjusting the set point based on any given chiller load and wet-bulb temperature of the outdoor air. A 5.6-113.4% increase in chiller COP can be achieved from the new condenser design and condenser fan operation. This provides important insights into how to develop more energy-efficient air-cooled chillers

From cation to oxide: hydroxylation and condensation of aqueous complexes

International Nuclear Information System (INIS)

Jolivet, J.P.

1997-01-01

Hydroxylation, condensation and precipitation of metal cations in aqueous solution are briefly reviewed. Hydroxylation of aqueous complexes essentially depends on the format charge (oxidation state), the size and the pH of the medium. It is the step allowing the condensation reaction. Depending on the nature of complexes (aqua-hydroxo, oxo-hydroxo), the. mechanism of condensation is different, olation or ox-olation respectively. The first one leads to poly-cations or hydroxides more or less stable against dehydration. The second one leads to poly-anions or oxides. Oligomeric species (poly-cations, poly-anions) are form from charged monomer complexes while the formation of solid phases requires non-charged precursors. Because of their high lability, charged oligomers are never the precursors of solids phases. The main routes for the formation of solid phases from solution are studied with two important and representative elements, Al and Si. For Al 3+ ions, different methods (base addition in solution, thermo-hydrolysis, hydrothermal synthesis) are discussed in relation to the crystal structure of the solid phase obtained. For silicic species condensing by ox-olation, the role of acid or base catalysis on the morphology of gels is studied. The influence of complexing ligands on the processes and on the characteristics of solids (morphology of particles, basic salts and polymetallic oxides formation) is studied. (author)

Proceedings: Condenser technology conference

International Nuclear Information System (INIS)

Tsou, J.L.; Mussalli, Y.G.

1991-08-01

Seam surface condenser and associated systems performance strongly affects availability and heat rate in nuclear and fossil power plants. Thirty-six papers presented at a 1990 conference discuss research results, industry experience, and case histories of condenser problems and solutions. This report contains papers on life extension, performance improvement, corrosion and failure analysis, fouling prevention, and recommendation for future R ampersand D. The information represents recent work on condenser problems and solutions to improve the procurement, operation, and maintenance functions of power plant personnel. Several key points follow: A nuclear and a fossil power plant report show that replacing titanium tube bundles improves condenser availability and performance. One paper reports 10 years of experience with enhanced heat transfer tubes in utility condensers. The newly developed enhanced condenser tubes could further improve condensing heat transfer. A new resistance summation method improves the accuracy of condenser performance prediction, especially for stainless steel and titanium tubed condensers. Several papers describe improved condenser fouling monitoring techniques, including a review of zebra mussel issues

Condensate cleaning systems

International Nuclear Information System (INIS)

Yamamoto, Michiyoshi; Oosumi, Katsumi; Takashima, Yoshie; Mitani, Shinji.

1982-01-01

Purpose: To decrease the frequency for the backwash and regeneration operations due to the increase in the differential pressure resulted from claddings captured in a mixed floor type desalter, and decrease the amount of radioactive liquid wastes of claddings from the condensate systems by removing claddings with electromagnetic filters. Constitution: In an existent plant, a valves is disposed between a condensate pump and a mixed floor type desalter. A pipeway is branched from a condensate pipe between the condensate pipe and the valve, through which condensates are transferred by a pump to an electromagnetic filter such as of a high gradient type electromagntic filter to remove claddings, then returned to a condensate pipe between the valve and the mixed floor type desalter and, thereafter, are removed with ionic components in the mixed floor type desalter and fed to the reactor. (Yoshino, Y.)

The role of arterial chemoreceptors in the breath-by-breath augmentation of inspiratory effort in rabbits during airway occlusion or elastic loading.

Science.gov (United States)

Callanan, D; Read, D J

1974-08-01

1. The breath-by-breath augmentation of inspiratory effort in the five breaths following airway occlusion or elastic loading was assessed in anaesthetized rabbits from changes of airway pressure, diaphragm e.m.g. and lung volume.2. When the airway was occluded in animals breathing air, arterial O(2) tension fell by 20 mmHg and CO(2) tension rose by 7 mmHg within the time of the first five loaded breaths.3. Inhalation of 100% O(2) or carotid denervation markedly reduced the breath-by-breath progression but had little or no effect on the responses at the first loaded breath.4. These results indicate that the breath-by-breath augmentation of inspiratory effort following addition of a load is mainly due to asphyxial stimulation of the carotid bodies, rather than to the gradual emergence of a powerful load-compensating reflex originating in the chest-wall, as postulated by some workers.5. The small residual progression seen in animals breathing 100% O(2) or following carotid denervation was not eliminated (a) by combining these procedures or (b) by addition of gas to the lungs to prevent the progressive lung deflation which occurred during airway occlusion.6. Bilateral vagotomy, when combined with carotid denervation, abolished the residual breath-by-breath progression of inspiratory effort.

Analysis of Exhaled Breath for Disease Detection

Science.gov (United States)

Amann, Anton; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Ligor, Tomasz; Jezierski, Tadeusz; Pleil, Joachim; Risby, Terence

2014-06-01

Breath analysis is a young field of research with great clinical potential. As a result of this interest, researchers have developed new analytical techniques that permit real-time analysis of exhaled breath with breath-to-breath resolution in addition to the conventional central laboratory methods using gas chromatography-mass spectrometry. Breath tests are based on endogenously produced volatiles, metabolites of ingested precursors, metabolites produced by bacteria in the gut or the airways, or volatiles appearing after environmental exposure. The composition of exhaled breath may contain valuable information for patients presenting with asthma, renal and liver diseases, lung cancer, chronic obstructive pulmonary disease, inflammatory lung disease, or metabolic disorders. In addition, oxidative stress status may be monitored via volatile products of lipid peroxidation. Measurement of enzyme activity provides phenotypic information important in personalized medicine, whereas breath measurements provide insight into perturbations of the human exposome and can be interpreted as preclinical signals of adverse outcome pathways.

Condensation coefficient of water in a weak condensation state

International Nuclear Information System (INIS)

Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

2008-01-01

The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

Condensation coefficient of water in a weak condensation state

Science.gov (United States)

Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

2008-07-01

The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

Maintaining steam/condensate lines

International Nuclear Information System (INIS)

Russum, S.A.

1992-01-01

Steam and condensate systems must be maintained with the same diligence as the boiler itself. Unfortunately, they often are not. The water treatment program, critical to keeping the boiler at peak efficiency and optimizing operating life, should not stop with the boiler. The program must encompass the steam and condensate system as well. A properly maintained condensate system maximizes condensate recovery, which is a cost-free energy source. The fuel needed to turn the boiler feedwater into steam has already been provided. Returning the condensate allows a significant portion of that fuel cost to be recouped. Condensate has a high heat content. Condensate is a readily available, economical feedwater source. Properly treated, it is very pure. Condensate improves feedwater quality and reduces makeup water demand and pretreatment costs. Higher quality feedwater means more reliable boiler operation

Relationships between hippocampal activity and breathing patterns

DEFF Research Database (Denmark)

Harper, R M; Poe, G R; Rector, D M

1998-01-01

Single cell discharge, EEG activity, and optical changes accompanying alterations in breathing patterns, as well as the knowledge that respiratory musculature is heavily involved in movement and other behavioral acts, implicate hippocampal regions in some aspects of breathing control. The control...... is unlikely to reside in oscillatory breathing movements, because such patterns emerge in preparations retaining only the medulla (and perhaps only the spinal cord). However, momentary changes in breathing patterns induced by affect, startle, whole-body movement changes, or compensatory ventilatory changes...... of hippocampal contributions to breathing control should be viewed in the context that significant interactions exist between blood pressure changes and ventilation, and that modest breathing challenges, such as exposure to hypercapnia or to increased resistive loads, bring into action a vast array of brain...

Enhanced Condensation Heat Transfer

Science.gov (United States)

Rose, John Winston

The paper gives some personal observations on various aspects of enhanced condensation heat transfer. The topics discussed are external condensation (horizontal low-finned tubes and wire-wrapped tubes), internal condensation (microfin tubes and microchannels) and Marangoni condensation of binary mixtures.

BREATHE to Understand©

Science.gov (United States)

Swisa, Maxine

2015-01-01

BREATHE is an acronym for Breathe, Reflect, Empathize, Accept, Thank, Hearten, Engage. The addition of Understand allows for a holistic approach to living a healthy and balanced life both inside and outside the classroom. This paper took form as a result of my personal, spiritual journey, as well as my teaching practice. I noticed that the…

Quantification of volatile organic compounds in exhaled human breath. Acetonitrile as biomarker for passive smoking. Model for isoprene in human breath

International Nuclear Information System (INIS)

Prazeller, P.

2000-03-01

The topic of this thesis is the quantification of volatile organic compounds in human breath under various circumstances. The composition of exhaled breath reflects metabolic processes in the human body. Breath analysis is a non invasive technique which makes it most interesting especially for medical or toxicological applications. Measurements were done with Proton-Transfer-Reaction Mass-Spectrometry (PTR-MS). This technique combines the advantage of small fragmentation of chemical ionization with highly time resolved mass spectrometry. A big part of this work is about investigations of exposition due to tobacco smoke. After smoking cigarettes the initial increase and time dependence of some compounds in the human breath are monitored . The calculated decrease resulting only from breathing out the compounds is presented and compared to the measured decline in the breath. This allows the distinction whether breathing is the dominant loss of a compound or a different metabolic process remover it more efficiently. Acetonitrile measured in human breath is presented as a biomarker for exposition to tobacco smoke. Especially its use for quantification of passive smoking, the exposition to environmental tobacco smoke (ETS) is shown. The reached accuracy and the fast way of measuring of acetonitrile in human breath using PTR-MS offer a good alternative to common used biomarkers. Numerous publications have described measurements of breath isoprene in humans, and there has been a hope that breath isoprene analyses could be a non-invasive diagnostic tool to assess serum cholesterol levels or cholesterol synthesis rate. However, significant analytical problems in breath isoprene analysis and variability in isoprene levels with age, exercise, diet, etc. have limited the usefulness of these measurements. Here, we have applied proton-transfer-reaction mass spectrometry (PTR-MS) to this problem, allowing on-line detection of breath isoprene. We show that breath isoprene

Arrays of Hollow Silica Half-Nanospheres Via the Breath Figure Approach

KAUST Repository

Gao, Yangqin; Hou, Yuanfang; Beaujuge, Pierre

2015-01-01

Breath figures (BFs) are patterns of liquid droplets that usually form upon condensation on a cold surface. Earlier work has shown that BFs can be used to produce continuous films of porous honeycomb-structured patterns on various types of materials, paving the path to a number of important applications such as the manufacturing of highly ordered nano- and micron-sized templates, micro lenses, and superhydrophobic coatings. It is worth noting, however, that few new findings have been reported in this area in recent years, limiting pursuits of novel architectures and key applications. In this report, an alternative method is described by which arrays of hollow silica half-nanospheres can be produced via BF templates. In the present method, a chemical vapor deposition (CVD) protocol performed while the BF is formed on a glass substrate yields a nanostructured pattern of silica half-spheres, which size (100-700 nm) and density across the glass surface vary with substrate modification and with the relative rates of water condensation and hydrolysis from silica precursors (a process carried out at room temperature). This method of forming arrays of hollow half-nanospheres via the BF approach may be applicable to various other oxides and a broad range of substrates including large-area flexible plastics. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Arrays of Hollow Silica Half-Nanospheres Via the Breath Figure Approach

KAUST Repository

Gao, Yangqin

2015-04-21

Breath figures (BFs) are patterns of liquid droplets that usually form upon condensation on a cold surface. Earlier work has shown that BFs can be used to produce continuous films of porous honeycomb-structured patterns on various types of materials, paving the path to a number of important applications such as the manufacturing of highly ordered nano- and micron-sized templates, micro lenses, and superhydrophobic coatings. It is worth noting, however, that few new findings have been reported in this area in recent years, limiting pursuits of novel architectures and key applications. In this report, an alternative method is described by which arrays of hollow silica half-nanospheres can be produced via BF templates. In the present method, a chemical vapor deposition (CVD) protocol performed while the BF is formed on a glass substrate yields a nanostructured pattern of silica half-spheres, which size (100-700 nm) and density across the glass surface vary with substrate modification and with the relative rates of water condensation and hydrolysis from silica precursors (a process carried out at room temperature). This method of forming arrays of hollow half-nanospheres via the BF approach may be applicable to various other oxides and a broad range of substrates including large-area flexible plastics. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Condensed Matter Physics in Colombia is in its forties

Science.gov (United States)

Camacho, Angela

2015-03-01

Physics in Colombia started to develop in the 70's as a research part of basic sciences with the acquisition, at that time, of large research equipments such as x-rays and EPR. Experimental work was soon supplemented by theoretical investigations, which led to the formation of research groups in condensed matter. In the early 80's existed such groups in five universities. In this report we present, after a short history of the main steps that guided the initial research subjects, the major areas already developed and the minor research groups that are in the stage of consolidation. Currently this type of work is done at least in 20 universities. We also show the actual numbers of researchers, publications, PhD students and laboratories discriminated in gender to complete an overview of Condensed Matter Physics in Colombia. Finally, we present a short review of the main theoretical issues that have been worked in the last decade focusing on low dimensional systems, their structural and optical properties

Optoacoustic 13C-breath test analyzer

Science.gov (United States)

Harde, Hermann; Helmrich, Günther; Wolff, Marcus

2010-02-01

The composition and concentration of exhaled volatile gases reflects the physical ability of a patient. Therefore, a breath analysis allows to recognize an infectious disease in an organ or even to identify a tumor. One of the most prominent breath tests is the 13C-urea-breath test, applied to ascertain the presence of the bacterium helicobacter pylori in the stomach wall as an indication of a gastric ulcer. In this contribution we present a new optical analyzer that employs a compact and simple set-up based on photoacoustic spectroscopy. It consists of two identical photoacoustic cells containing two breath samples, one taken before and one after capturing an isotope-marked substrate, where the most common isotope 12C is replaced to a large extent by 13C. The analyzer measures simultaneously the relative CO2 isotopologue concentrations in both samples by exciting the molecules on specially selected absorption lines with a semiconductor laser operating at a wavelength of 2.744 μm. For a reliable diagnosis changes of the 13CO2 concentration of 1% in the exhaled breath have to be detected at a concentration level of this isotope in the breath of about 500 ppm.

New breathing functions for the transverse breathing crack of the cracked rotor system: Approach for critical and subcritical harmonic analysis

Science.gov (United States)

Al-Shudeifat, Mohammad A.; Butcher, Eric A.

2011-01-01

The actual breathing mechanism of the transverse breathing crack in the cracked rotor system that appears due to the shaft weight is addressed here. As a result, the correct time-varying area moments of inertia for the cracked element cross-section during shaft rotation are also determined. Hence, two new breathing functions are identified to represent the actual breathing effect on the cracked element stiffness matrix. The new breathing functions are used in formulating the time-varying finite element stiffness matrix of the cracked element. The finite element equations of motion are then formulated for the cracked rotor system and solved via harmonic balance method for response, whirl orbits and the shift in the critical and subcritical speeds. The analytical results of this approach are compared with some previously published results obtained using approximate formulas for the breathing mechanism. The comparison shows that the previously used breathing function is a weak model for the breathing mechanism in the cracked rotor even for small crack depths. The new breathing functions give more accurate results for the dynamic behavior of the cracked rotor system for a wide range of the crack depths. The current approach is found to be efficient for crack detection since the critical and subcritical shaft speeds, the unique vibration signature in the neighborhood of the subcritical speeds and the sensitivity to the unbalance force direction all together can be utilized to detect the breathing crack before further damage occurs.

Optimising diffusion-weighted MR imaging for demonstrating pancreatic cancer: a comparison of respiratory-triggered, free-breathing and breath-hold techniques

International Nuclear Information System (INIS)

Kartalis, Nikolaos; Loizou, Louiza; Edsborg, Nick; Albiin, Nils; Segersvaerd, Ralf

2012-01-01

To compare respiratory-triggered, free-breathing, and breath-hold DWI techniques regarding (1) image quality, and (2) signal intensity (SI) and ADC measurements in pancreatic ductal adenocarcinoma (PDAC). Fifteen patients with histopathologically proven PDAC underwent DWI prospectively at 1.5 T (b = 0, 50, 300, 600 and 1,000 s/mm 2 ) with the three techniques. Two radiologists, independently and blindly, assigned total image quality scores [sum of rating diffusion images (lesion detection, anatomy, presence of artefacts) and ADC maps (lesion characterisation, overall image quality)] per technique and ranked them. The lesion SI, signal-to-noise ratio, mean ADC and coefficient of variation (CV) were compared. Total image quality scores for respiratory-triggered, free-breathing and breath-hold techniques were 17.9, 16.5 and 17.1 respectively (respiratory-triggered was significantly higher than free-breathing but not breath-hold). The respiratory-triggered technique had a significantly higher ranking. Lesion SI on all b-values and signal-to-noise ratio on b300 and b600 were significantly higher for the respiratory-triggered technique. For respiratory-triggered, free-breathing and breath-hold techniques the mean ADCs were 1.201, 1.132 and 1.253 x 10 -3 mm 2 /s, and mean CVs were 8.9, 10.8 and 14.1 % respectively (respiratory-triggered and free-breathing techniques had a significantly lower mean CV than the breath-hold technique). In both analyses, respiratory-triggered DWI showed superiority and seems the optimal DWI technique for demonstrating PDAC. (orig.)

Relationships between breath ratios, spirituality and health ...

African Journals Online (AJOL)

The aim of this retrospective, quantitative study was to investigate relationships between breath ratios, spirituality perceptions and health perceptions, with special reference to breath ratios that best predict optimal health and spirituality. Significant negative correlations were found between breath ratios and spirituality ...

Cardiorespiratory interactions during resistive load breathing.

Science.gov (United States)

Calabrese, P; Perrault, H; Dinh, T P; Eberhard, A; Benchetrit, G

2000-12-01

The addition to the respiratory system of a resistive load results in breathing pattern changes and in negative intrathoracic pressure increases. The aim of this study was to use resistive load breathing as a stimulus to the cardiorespiratory interaction and to examine the extent of the changes in heart rate variability (HRV) and respiratory sinus arrhythmia (RSA) in relation to the breathing pattern changes. HRV and RSA were studied in seven healthy subjects where four resistive loads were applied in a random order during the breath and 8-min recording made in each condition. The HRV spectral power components were computed from the R-R interval sequences, and the RSA amplitude and phase were computed from the sinusoid fitting the instantaneous heart rate within each breath. Adding resistive loads resulted in 1) increasing respiratory period, 2) unchanging heart rate, and 3) increasing HRV and changing RSA characteristics. HRV and RSA characteristics are linearly correlated to the respiratory period. These modifications appear to be linked to load-induced changes in the respiratory period in each individual, because HRV and RSA characteristics are similar at a respiratory period obtained either by loading or by imposed frequency breathing. The present results are discussed with regard to the importance of the breathing cycle duration in these cardiorespiratory interactions, suggesting that these interactions may depend on the time necessary for activation and dissipation of neurotransmitters involved in RSA.

High-pitch coronary CT angiography in dual-source CT during free breathing vs. breath holding in patients with low heart rates

Energy Technology Data Exchange (ETDEWEB)

Bischoff, Bernhard, E-mail: bernhard.bischoff@med.uni-muenchen.de [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich (Germany); DZHK (German Centre for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich (Germany); Meinel, Felix G. [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich (Germany); DZHK (German Centre for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich (Germany); Del Prete, Alessandra [Department of Radiology Magrassi-Lanzara, Second University of Naples, Naples (Italy); Reiser, Maximilian F.; Becker, Hans-Christoph [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich (Germany); DZHK (German Centre for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich (Germany)

2013-12-01

Background: Coronary CT angiography (CCTA) is usually performed during breath holding to reduce motion artifacts caused by respiration. However, some patients are not able to follow the breathing commands adequately due to deafness, hearing impairment, agitation or pulmonary diseases. The aim of this study was to evaluate the potential of high-pitch CCTA in free breathing patients when compared to breath holding patients. Methods: In this study we evaluated 40 patients (20 free breathing and 20 breath holding patients) with a heart rate of 60 bpm or below referred for CCTA who were examined on a 2nd generation dual-source CT system. Image quality of each coronary artery segment was rated using a 4-point grading scale (1: non diagnostic–4: excellent). Results: Mean heart rate during image acquisition was 52 ±5 bpm in both groups. There was no significant difference in mean image quality, slightly favoring image acquisition during breath holding (mean image quality score 3.76 ± 0.32 in breath holding patients vs. 3.61 ± 0.45 in free breathing patients; p = 0.411). Due to a smaller amount of injected contrast medium, there was a trend for signal intensity to be slightly lower in free breathing patients, but this was not statistically significant (435 ± 123 HU vs. 473 ± 117 HU; p = 0.648). Conclusion: In patients with a low heart rate who are not able to hold their breath adequately, CCTA can also be acquired during free breathing without substantial loss of image quality when using a high pitch scan mode in 2nd generation dual-source CT.

Efficacy of a Respiratory Training System on the Regularity of Breathing

International Nuclear Information System (INIS)

Shin, Eun Hyuk; Park, Hee Chul; Han, Young Yih; Ju, Sang Gyu; Shin, Jung Suk; Ahn, Yong Chan

2008-01-01

In order to enhance the efficiency of respiratory gated 4-dimensional radiation therapy for more regular and stable respiratory period and amplitude, a respiration training system was designed, and its efficacy was evaluated. Materials and Methods: The experiment was designed to measure the difference in respiration regularity following the use of a training system. A total of 11 subjects (9 volunteers and 2 patients) were included in the experiments. Three different breathing signals, including free breathing (free-breathing), guided breathing that followed training software (guided-breathing), and free breathing after the guided-breathing (post guided-breathing), were consecutively recorded in each subject. The peak-to-peak (PTP) period of the breathing signal, standard deviation (SD), peak-amplitude and its SD, area of the one cycle of the breathing wave form, and its root mean square (RMS) were measured and computed. Results: The temporal regularity was significantly improved in guided-breathing since the SD of breathing period reduced (free-breathing 0.568 vs guided-breathing 0.344, p=0.0013). The SD of the breathing period representing the post guided-breathing was also reduced, but the difference was not statistically significant (free-breathing 0.568 vs. guided-breathing 0.512, p=ns). Also the SD of measured amplitude was reduced in guided-breathing (free-breathing 1.317 vs. guided-breathing 1.068, p=0.187), although not significant. This indicated that the tidal volume for each breath was kept more even in guided-breathing compared to free-breathing. There was no change in breathing pattern between free-breathing and guided-breathing. The average area of breathing wave form and its RMS in postguided-breathing, however, was reduced by 7% and 5.9%, respectively. Conclusion: The guided-breathing was more stable and regular than the other forms of breathing data. Therefore, the developed respiratory training system was effective in improving the temporal

Patients' experiences of breathing retraining for asthma: a qualitative process analysis of participants in the intervention arms of the BREATHE trial.

OpenAIRE

Arden-Close, E; Yardley, L; Kirby, S; Thomas, M; Bruton, A

2017-01-01

Poor symptom control and impaired quality of life are common in adults with asthma, and breathing retraining exercises may be an effective method of self-management. This study aimed to explore the experiences of participants in the intervention arms of the BREATHE trial, which investigated the effectiveness of breathing retraining as a mode of asthma management. Sixteen people with asthma (11 women, 8 per group) who had taken part in the intervention arms of the BREATHE trial (breathing retr...

Patients' experiences of breathing retraining for asthma: a qualitative process analysis of participants in the intervention arms of the BREATHE trial.

Science.gov (United States)

Arden-Close, Emily; Yardley, Lucy; Kirby, Sarah; Thomas, Mike; Bruton, Anne

2017-10-05

Poor symptom control and impaired quality of life are common in adults with asthma, and breathing retraining exercises may be an effective method of self-management. This study aimed to explore the experiences of participants in the intervention arms of the BREATHE trial, which investigated the effectiveness of breathing retraining as a mode of asthma management. Sixteen people with asthma (11 women, 8 per group) who had taken part in the intervention arms of the BREATHE trial (breathing retraining delivered by digital versatile disc (DVD) or face-to-face sessions with a respiratory physiotherapist) took part in semi-structured telephone interviews about their experiences. Interviews were analysed using thematic analysis. Breathing retraining was perceived positively as a method of asthma management. Motivations for taking part included being asked, to enhance progress in research, to feel better/reduce symptoms, and to reduce medication. Participants were positive about the physiotherapist, liked having the materials tailored, found meetings motivational, and liked the DVD and booklet. The impact of breathing retraining following regular practice included increased awareness of breathing and development of new habits. Benefits of breathing retraining included increased control over breathing, reduced need for medication, feeling more relaxed, and improved health and quality of life. Problems included finding time to practice the exercises, and difficulty mastering techniques. Breathing retraining was acceptable and valued by almost all participants, and many reported improved wellbeing. Face to face physiotherapy was well received. However, some participants in the DVD group mentioned being unable to master techniques. PATIENTS RECEPTIVE TO BREATHING RETRAINING: Patients with asthma taught how to change their unconscious breathing patterns generally like non-pharmacological interventions. Researchers in the UK, led by Mike Thomas from the University of Southampton

Towards The Design of a Smartphone-Based Biofeedback Breathing Training: Identifying Diaphragmatic Breathing Patterns from a Smartphone’s Microphone

OpenAIRE

Shih, Chen-Hsuan Iris; Kowatsch, Tobias; Tinschert, Peter; Barata, Filipe; Nißen, Marcia Katharina

2016-01-01

Asthma, diabetes, hypertension, or major depression are non-communicable diseases (NCDs) and impose a major burden on global health. Stress is linked to both the causes and consequences of NCDs and it has been shown that biofeedback-based breathing trainings (BBTs) are effective in coping with stress. Here, diaphragmatic breathing, i.e. deep abdominal breathing, belongs to the most distinguished breathing techniques. However, high costs and low scalability of state-of-the-art BBTs that requir...

Optimising diffusion-weighted MR imaging for demonstrating pancreatic cancer: a comparison of respiratory-triggered, free-breathing and breath-hold techniques

Energy Technology Data Exchange (ETDEWEB)

Kartalis, Nikolaos; Loizou, Louiza; Edsborg, Nick; Albiin, Nils [Karolinska University Hospital, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm (Sweden); Segersvaerd, Ralf [Karolinska University Hospital, Division of Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm (Sweden)

2012-10-15

To compare respiratory-triggered, free-breathing, and breath-hold DWI techniques regarding (1) image quality, and (2) signal intensity (SI) and ADC measurements in pancreatic ductal adenocarcinoma (PDAC). Fifteen patients with histopathologically proven PDAC underwent DWI prospectively at 1.5 T (b = 0, 50, 300, 600 and 1,000 s/mm{sup 2}) with the three techniques. Two radiologists, independently and blindly, assigned total image quality scores [sum of rating diffusion images (lesion detection, anatomy, presence of artefacts) and ADC maps (lesion characterisation, overall image quality)] per technique and ranked them. The lesion SI, signal-to-noise ratio, mean ADC and coefficient of variation (CV) were compared. Total image quality scores for respiratory-triggered, free-breathing and breath-hold techniques were 17.9, 16.5 and 17.1 respectively (respiratory-triggered was significantly higher than free-breathing but not breath-hold). The respiratory-triggered technique had a significantly higher ranking. Lesion SI on all b-values and signal-to-noise ratio on b300 and b600 were significantly higher for the respiratory-triggered technique. For respiratory-triggered, free-breathing and breath-hold techniques the mean ADCs were 1.201, 1.132 and 1.253 x 10{sup -3} mm{sup 2}/s, and mean CVs were 8.9, 10.8 and 14.1 % respectively (respiratory-triggered and free-breathing techniques had a significantly lower mean CV than the breath-hold technique). In both analyses, respiratory-triggered DWI showed superiority and seems the optimal DWI technique for demonstrating PDAC. (orig.)

Measurement of liquid-liquid equilibria for condensate + glycol and condensate + glycol + water systems

DEFF Research Database (Denmark)

Riaz, Muhammad; Kontogeorgis, Georgios; Stenby, Erling Halfdan

2011-01-01

,2-ethanediol (MEG) + condensate and MEG + water + condensate systems at temperatures from (275 to 323) K at atmospheric pressure. The condensate used in this work is a stabilized natural gas condensate from an offshore field in the North Sea. Compositional analysis of the natural gas condensate was carried out...... by gas chromatography, and detailed separation of individual condensate's components has been carried out. Approximately 85 peaks eluting before nonane were identified by their retention time. Peak areas were converted to mass fraction using 1-heptene as an internal standard. The components were divided...... into boiling range groups from hexane to nonane. Paraffinic (P), naphthenic (N), and aromatic (A) distributions were obtained for the boiling point fractions up to nonane. The average molar mass and the overall density of the condensate were measured experimentally. For the mutual solubility of MEG...

Sports-related lung injury during breath-hold diving

Directory of Open Access Journals (Sweden)

Tanja Mijacika

2016-12-01

Full Text Available The number of people practising recreational breath-hold diving is constantly growing, thereby increasing the need for knowledge of the acute and chronic effects such a sport could have on the health of participants. Breath-hold diving is potentially dangerous, mainly because of associated extreme environmental factors such as increased hydrostatic pressure, hypoxia, hypercapnia, hypothermia and strenuous exercise. In this article we focus on the effects of breath-hold diving on pulmonary function. Respiratory symptoms have been reported in almost 25% of breath-hold divers after repetitive diving sessions. Acutely, repetitive breath-hold diving may result in increased transpulmonary capillary pressure, leading to noncardiogenic oedema and/or alveolar haemorrhage. Furthermore, during a breath-hold dive, the chest and lungs are compressed by the increasing pressure of water. Rapid changes in lung air volume during descent or ascent can result in a lung injury known as pulmonary barotrauma. Factors that may influence individual susceptibility to breath-hold diving-induced lung injury range from underlying pulmonary or cardiac dysfunction to genetic predisposition. According to the available data, breath-holding does not result in chronic lung injury. However, studies of large populations of breath-hold divers are necessary to firmly exclude long-term lung damage.

Low pressure lithium condensation

International Nuclear Information System (INIS)

Wadkins, R.P.; Oh, C.H.

1985-01-01

A low pressure experiment to evaluate the laminar film condensation coefficients of lithium was conducted. Some thirty-six different heat transfer tests were made at system pressures ranging from 1.3 to 26 Pa. Boiled lithium was condensed on the inside of a 7.6-cm (ID), 409 stainless-steel pipe. Condensed lithium was allowed to reflux back to the pool boiling region below the condensing section. Fourteen chromel/alumel thermocouples were attached in various regions of the condensing section. The thermocouples were initially calibrated with errors of less than one degree Celsius

21 CFR 868.5240 - Anesthesia breathing circuit.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anesthesia breathing circuit. 868.5240 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5240 Anesthesia breathing circuit. (a) Identification. An anesthesia breathing circuit is a device that is intended to administer medical gases to a...

CO{sub 2} injection as pH regulator in refrigeration circuits; Inyeccion de CO{sub 2} como regulador de pH en circuitos de refrigeracion

Energy Technology Data Exchange (ETDEWEB)

Belinchon, J.

2009-07-01

Water from rivers is not usually suitable for use in cooling circuits of industrial installations, normally because of its high fouling ability. this requires a treatment before use based on the use of fouling inhibitors, biocides and pH regulators. The most commonly used pH regulator is sulfuric acid, a very hazardous chemical product that also generates secondary saline contamination due to the sulfates. Since 2008, Iberdrola Generation, in collaboration with Air Liquid, has been carrying out a pilot project in Cofrentes Nuclear Power Plant focusing on the use of CO{sub 2} as an acidifier of the main condenser cooling system. (Author)

ABA-Cloud: support for collaborative breath research.

Science.gov (United States)

Elsayed, Ibrahim; Ludescher, Thomas; King, Julian; Ager, Clemens; Trosin, Michael; Senocak, Uygar; Brezany, Peter; Feilhauer, Thomas; Amann, Anton

2013-06-01

This paper introduces the advanced breath analysis (ABA) platform, an innovative scientific research platform for the entire breath research domain. Within the ABA project, we are investigating novel data management concepts and semantic web technologies to document breath analysis studies for the long run as well as to enable their full automatic reproducibility. We propose several concept taxonomies (a hierarchical order of terms from a glossary of terms), which can be seen as a first step toward the definition of conceptualized terms commonly used by the international community of breath researchers. They build the basis for the development of an ontology (a concept from computer science used for communication between machines and/or humans and representation and reuse of knowledge) dedicated to breath research.

Optimal ventilatory patterns in periodic breathing.

Science.gov (United States)

Ghazanshahi, S D; Khoo, M C

1993-01-01

The goal of this study was to determine whether periodic breathing (PB), which is highly prevalent during sleep at high altitudes, imposes physiological penalties on the respiratory system in the absence of any accompanying disease. Using a computer model of respiratory gas exchange, we compared the effects of a variety of PB patterns on the chemical and mechanical costs of breathing to those resulting from regular tidal breathing. Although PB produced considerable fluctuation in arterial blood gas tensions, for the same cycle-averaged ventilation, higher arterial oxygen saturation and lower arterial carbon dioxide levels were achieved. This result can be explained by the fact that the combination of large breaths and apnea in PB leads to a substantial reduction in dead space ventilation. At the same time, the savings in mechanical cost achieved by the respiratory muscles during apnea partially offset the increase during the breathing phase. Consequently, the "pressure cost," a criterion based on mean inspiratory pressure, was elevated only slightly, although the average work rate of breathing increased significantly. We found that, at extreme altitudes, PB patterns with clusters of 2 to 4 large breaths that alternate with apnea produce the highest arterial oxygenation levels and lowest pressure costs. The common occurrence of PB patterns with closely similar features has been reported in sleeping healthy sojourners at extreme altitudes. Taken together, these findings suggest that PB favors a reduction in the oxygen demands of the respiratory muscles and therefore may not be as detrimental as it is generally believed to be.

[Wastewater from the condensation and drying section of ABS was pretreated by microelectrolysis].

Science.gov (United States)

Lai, Bo; Qin, Hong-Ke; Zhou, Yue-Xi; Song, Yu-Dong; Cheng, Jia-Yun; Sun, Li-Dong

2011-04-01

Wastewater from the condensation and drying section of acrylonitrile-butadiene-styrene (ABS) resin plant was pretreated by the microelectrolysis, and the effect of the influent pH value on the pollution removal efficiency of the microelectrolysis was mainly studied. In order to study the electrochemical action of the microelectrolysis for the degradation of toxic refractory organic pollutants, two control experiments of activated carbon and iron were set up. The results showed that the TOC removal efficiencies were all fluctuated between 40% and 60% under the condition of different influent pH values. The microelectrolysis can decompose and transform the toxic refractory organic pollutants and increase the BOD5/COD ratio from 0.32 to 0.60, which increased the biodegradability of ABS resin wastewater significantly. When the pH value of influent was 4.0, the BOD5/COD ratio of effluent reached 0.71. The result of UV-vis spectra indicates that the removal efficiency of the organic nitrile was the highest with influent pH was 4.0. Therefore, the best influent pH value of microelectrolysis was 4.0.

46 CFR 197.340 - Breathing gas supply.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing gas supply. 197.340 Section 197.340 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.340 Breathing gas supply. (a) A primary breathing gas supply for surface-supplied diving must be sufficient to support the following for the...

Bad Breath

Science.gov (United States)

... cabbage. And of course smoking causes its own bad smell. Some diseases and medicines can cause a specific breath odor. Having good dental habits, like brushing and flossing regularly, help fight bad ...

Aspects of hyperspherical adiabaticity in an atomic-gas Bose-Einstein condensate

International Nuclear Information System (INIS)

Kushibe, Daisuke; Mutou, Masaki; Morishita, Toru; Watanabe, Shinichi; Matsuzawa, Michio

2004-01-01

Excitation of an atomic-gas Bose-Einstein condensate (BEC) in the zeroth-order ground-state channel is studied with the hyperspherical adiabatic method of Bohn et al. [Bohn et al., Phys. Rev. A 58, 584 (1998)] suitably generalized to accommodate the anisotropic trapping potential. The method exploits the system's size as an adiabatic parameter so that the explicit size dependence is immediately conducive to the virial theorem. The oscillation frequencies associated with the monopole (breathing) and quadrupole modes thus emerge naturally and converge to the well-known Thomas-Fermi limits. Analysis of the single-particle density and the projected excitation wave function shows that the excitation in the single hyperspherical ground-state channel merely represents a progressive increase in occupancy of the first excited single-particle state. The work paves the way for applying the adiabatic picture to other BEC phenomena

SLAC synchronous condenser

International Nuclear Information System (INIS)

Corvin, C.

1995-06-01

A synchronous condenser is a synchronous machine that generates reactive power that leads real power by 90 degrees in phase. The leading reactive power generated by the condenser offsets or cancels the normal lagging reactive power consumed by inductive and nonlinear loads at the accelerator complex. The quality of SLAC's utility power is improved with the addition of the condenser. The inertia of the condenser's 35,000 pound rotor damps and smoothes voltage excursions on two 12 kilovolt master substation buses, improving voltage regulation site wide. The condenser absorbs high frequency transients and noise in effect ''scrubbing'' the electric system power at its primary distribution source. In addition, the condenser produces a substantial savings in power costs. Federal and investor owned utilities that supply electric power to SLAC levy a monthly penalty for lagging reactive power delivered to the site. For the 1993 fiscal year this totaled over $285,000 in added costs for the year. By generating leading reactive power on site, thereby reducing total lagging reactive power requirements, a substantial savings in electric utility bills is achieved. Actual savings of $150,000 or more a year are possible depending on experimental operations

46 CFR 197.312 - Breathing supply hoses.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing supply hoses. 197.312 Section 197.312 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.312 Breathing supply hoses. (a) Each breathing supply hose must— (1) Have a maximum working pressure that is equal to or exceeds— (i) The maximum...

Volatile sulphur compounds in morning breath of human volunteers.

NARCIS (Netherlands)

Snel, J.; Burgering, M.; Smit, B.; Noordman, W.; Tangerman, A.; Winkel, E.G.; Kleerebezem, M.

2011-01-01

OBJECTIVE: morning breath contains elevated concentrations of volatile sulphur components (VSCs). Therefore, morning breath is recognised as a surrogate target for interventions on breath quality. Nevertheless, factors influencing morning breath are poorly understood. Our aim was to evaluate

Volatile sulphur compounds in morning breath of human volunteers

NARCIS (Netherlands)

Snel, Johannes; Burgering, Maurits; Smit, Bart; Noordman, Wouter; Tangerman, Albert; Winkel, Edwin G.; Kleerebezem, Michiel

Objective: Morning breath contains elevated concentrations of volatile sulphur components (VSCs). Therefore, morning breath is recognised as a surrogate target for interventions on breath quality. Nevertheless, factors influencing morning breath are poorly understood. Our aim was to evaluate

Conditions for maximum isolation of stable condensate during separation in gas-condensate systems

Energy Technology Data Exchange (ETDEWEB)

Trivus, N.A.; Belkina, N.A.

1969-02-01

A thermodynamic analysis is made of the gas-liquid separation process in order to determine the relationship between conditions of maximum stable condensate separation and physico-chemical nature and composition of condensate. The analysis was made by considering the multicomponent gas-condensate fluid produced from Zyrya field as a ternary system, composed of methane, an intermediate component (propane and butane) and a heavy residue, C/sub 6+/. Composition of 5 ternary systems was calculated for a wide variation in separator conditions. At each separator pressure there is maximum condensate production at a certain temperature. This occurs because solubility of condensate components changes with temperature. Results of all calculations are shown graphically. The graphs show conditions of maximum stable condensate separation.

Padrão respiratório e movimento toracoabdominal de crianças respiradoras orais Breathing pattern and thoracoabdominal motion in mouth-breathing children

Directory of Open Access Journals (Sweden)

TCS Brant

2008-12-01

motion of mouth-breathing children aged between eight and ten years and to compare these characteristics with those of nose-breathing children of the same ages. METHODS: This observational study was carried out in a university laboratory. The sample size of 50 subjects was estimated based on the results of a pilot study with ten children in each group (total of 20 children and considering a significance level of 0.05 and statistical power of 0.80. Twenty-six mouth-breathing and 25 nose-breathing children participated. Calibrated respiratory inductive plethysmography was used to analyze the following variables, among others: respiratory frequency (f, rib cage contribution towards tidal volume (%RC/Vt, phase angle (PhAng and the ratio between time taken to reach peak inspiratory flow and total inspiratory time (PifT/Ti. Peripheral oxygen saturation of hemoglobin (SpO2 was measured using pulse oximetry. Statistical analysis was performed using the Student's t test for independent groups or the Mann-Whitney U test, according to the sample distribution of the variables. RESULTS: A total of 4,816 respiratory cycles were analyzed: 2,455 from mouth-breathers and 2,361 from nose-breathers, with a mean of 94 cycles per child. No statistically significant differences were observed between the groups, for the variables studied (f=20.00±2.68 versus 20.73±2.58, p=0.169; %RC/Vt=39.30±11.86 versus 38.36±10.93, p=0.769; PhAng=14.53±7.97 versus 13.31±7.74, p=0.583; PifT/Ti=57.40±7.16 versus 58.35±5.99, p=0.610; SpO2=96.42±1.52% versus 96.88± 1.01%, p=0.208; respectively. CONCLUSIONS: These results suggest that mouth-breathing children show breathing patterns and thoracoabdominal motion that are similar to those of nose-breathing children in the same age group.

Sudarshan kriya yoga: Breathing for health

Directory of Open Access Journals (Sweden)

Sameer A Zope

2013-01-01

Full Text Available Breathing techniques are regularly recommended for relaxation, stress management, control of psychophysiological states, and to improve organ function. Yogic breathing, defined as a manipulation of breath movement, has been shown to positively affect immune function, autonomic nervous system imbalances, and psychological or stress-related disorders. The aim of this study was to assess and provide a comprehensive review of the physiological mechanisms, the mind-body connection, and the benefits of Sudarshan Kriya Yoga (SKY in a wide range of clinical conditions. Various online databases searched were Medline, Psychinfo, EMBASE, and Google Scholar. All the results were carefully screened and articles on SKY were selected. The references from these articles were checked to find any other potentially relevant articles. SKY, a unique yogic breathing practice, involves several types of cyclical breathing patterns, ranging from slow and calming to rapid and stimulating. There is mounting evidence to suggest that SKY can be a beneficial, low-risk, low-cost adjunct to the treatment of stress, anxiety, post-traumatic stress disorder, depression, stress-related medical illnesses, substance abuse, and rehabilitation of criminal offenders.

Bad Breath

Science.gov (United States)

... garlic, onions, cheese, orange juice, and soda poor dental hygiene (say: HI-jeen), meaning not brushing and flossing regularly smoking and other tobacco use Poor oral hygiene leads to bad breath because when food particles ...

Breathing Difficulties

Science.gov (United States)

... symptoms. Symptoms associated with weak respiratory muscles: Air “hunger” (gasping, labored breathing) with an without activity Fatigue ... Start your own fundraising event & help create a world without ALS Start an Event Site Map | Press ...

Proteomics analysis of Fusarium proliferatum under various initial pH during fumonisin production.

Science.gov (United States)

Li, Taotao; Gong, Liang; Wang, Yong; Chen, Feng; Gupta, Vijai Kumar; Jian, Qijie; Duan, Xuewu; Jiang, Yueming

2017-07-05

Fusarium proliferatum as a fungal pathogen can produce fumonisin which causes a great threat to animal and human health. Proteomic approach was a useful tool for investigation into mycotoxin biosynthesis in fungal pathogens. In this study, we analyzed the fumonisin content and mycelium proteins of Fusarium proliferatum cultivated under the initial pH5 and 10. Fumonisin production after 10days was significantly induced in culture condition at pH10 than pH5. Ninety nine significantly differently accumulated protein spots under the two pH conditions were detected using two dimensional polyacrylamide gel electrophoresis and 89 of these proteins were successfully identified by MALDI-TOF/TOF and LC-ESI-MS/MS analysis. Among these 89 proteins, 45 were up-regulated at pH10 while 44 were up-accumulated at pH5. At pH10, these proteins were found to involve in the modification of fumonisin backbone including up-regulated polyketide synthase, cytochrome P450, S-adenosylmethionine synthase and O-methyltransferase, which might contribute to the induction of fumonisin production. At pH5, these up-regulated proteins such as l-amino-acid oxidase, isocitrate dehydrogenase and citrate lyase might inhibit the condensation of fumonisin backbone, resulting in reduced production of fumonisins. These results may help us to understand the molecular mechanism of the fumonisin synthesis in F. proliferatum. To extend our understanding of the mechanism of the fumonisin biosynthesis of F. proliferatum, we reported the fumonisin production in relation to the differential proteins of F. proliferatum mycelium under two pH culture conditions. Among these 89 identified spots, 45 were up-accumulated at pH10 while 44 were up-accumulated at pH5. Our results revealed that increased fumonisin production at pH10 might be related to the induction of fumonisin biosynthesis caused by up-regulation of polyketide synthase, cytochrome P450, S-adenosylmethionine synthase and O-methyltransferase. Meanwhile, the

Transcriptomic Analysis of Compromise Between Air-Breathing and Nutrient Uptake of Posterior Intestine in Loach (Misgurnus anguillicaudatus), an Air-Breathing Fish.

Science.gov (United States)

Huang, Songqian; Cao, Xiaojuan; Tian, Xianchang

2016-08-01

Dojo loach (Misgurnus anguillicaudatus) is an air-breathing fish species by using its posterior intestine to breathe on water surface. So far, the molecular mechanism about accessory air-breathing in fish is seldom addressed. Five cDNA libraries were constructed here for loach posterior intestines form T01 (the initial stage group), T02 (mid-stage of normal group), T03 (end stage of normal group), T04 (mid-stage of air-breathing inhibited group), and T05 (the end stage of air-breathing inhibited group) and subjected to perform RNA-seq to compare their transcriptomic profilings. A total of 92,962 unigenes were assembled, while 37,905 (40.77 %) unigenes were successfully annotated. 2298, 1091, and 3275 differentially expressed genes (fn1, ACE, EGFR, Pxdn, SDF, HIF, VEGF, SLC2A1, SLC5A8 etc.) were observed in T04/T02, T05/T03, and T05/T04, respectively. Expression levels of many genes associated with air-breathing and nutrient uptake varied significantly between normal and intestinal air-breathing inhibited group. Intraepithelial capillaries in posterior intestines of loaches from T05 were broken, while red blood cells were enriched at the surface of intestinal epithelial lining with 241 ± 39 cells per millimeter. There were periodic acid-schiff (PAS)-positive epithelial mucous cells in posterior intestines from both normal and air-breathing inhibited groups. Results obtained here suggested an overlap of air-breathing and nutrient uptake function of posterior intestine in loach. Intestinal air-breathing inhibition in loach would influence the posterior intestine's nutrient uptake ability and endothelial capillary structure stability. This study will contribute to our understanding on the molecular regulatory mechanisms of intestinal air-breathing in loach.

The assessment of the breath hold and the free breath methods about the blood flow evaluation by using phase contrast MRI

Energy Technology Data Exchange (ETDEWEB)

Kim, Seong Ho [Dept. of Radiology, Konkuk Medical center, Seoul (Korea, Republic of)

2016-06-15

Measurement of cardiac blood flow using the magnetic resonance imaging has been limited due to breathing and involuntary movements of the heart. The present study attempted to improve the accuracy of cardiac blood flow testing through phase contrast magnetic resonance imaging by presenting the adequate breathing method and imaging variables by comparing the measurement values of cardiac blood flow. Each was evaluated by comparing the breath hold retrospective 1NEX and non breath hold retrospective 1-3NEX in the ascending aorta and descending aorta. As a result, the average blood flow amount/ velocity of the breath hold retrosepctive 1NEX method in the ascending aorta were 96.17±19.12 ml/sec, 17.04±4.12 cm/sec respectively, which demonstrates a statistically significant difference(p<0.05) with the non-breath hold retrospective method 1NEX of 72.31±13.27 ml and 12.32±3.85. On the other hand, the average 2NEX blood flow and mean flow velocity is 101.90±24.09, 16.84±4.32, 3NEX 103.06±25.49, 16.88±4.19 did not show statistically significant differences(p>0.05).The average blood flow amount/ velocity of the breath hold retrospective 1NEX method in the descending aorta were 76.68±19.72 ml/s, and 22.23±4.8, which did not demonstrate a significant difference in comparison to non-breath hold retrospective method 1-3 NEX. Therefore, the non breath hold retrospective method does not significantly differ in terms of cardiac blood flow in comparison with the breath hold retrospective method in accordance with the increase of NEX, so pediatric patients or patients who are not able to breathe well must have the diagnostic value of their cardiac blood flow tests improved.

How to breathe when you are short of breath

Science.gov (United States)

... you: Watch TV Use your computer Read a newspaper How to do Pursed lip Breathing The steps ... of Medicine, Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also ...

Effects of non-condensable gas on the condensation of steam

International Nuclear Information System (INIS)

Jackson, J.D.; An, P.; Reinert, A.; Ahmadinejad, M.

2000-01-01

The experimental work reported here was undertaken with the aim of extending the database currently available on the condensation of steam in the presence of non-condensable gases and thereby improving the empirical input to thermal-hydraulic codes which might be used for design and safety assessment of advanced water-cooled nuclear reactors. Heat was removed from flowing mixtures of steam and air in a test section by means of a water-cooled condensing plate. The test facility constructed for the study incorporates a degassing unit which supplies water to a boiler. This delivers steam steadily to a mixing chamber where it joins with a flow of preheated air. The mixture of steam and air is supplied to the bottom of a cylindrical test section in which it flows upwards over a double sided condensing plate which can be vertical, inclined or horizontal, The rate at which heat is removed by cooling water flowing through internal passages in the plate can de determined calorimetrically knowing the flow rate of the water and its temperature rise. After commissioning experiments had shown that reliable measurements of condensation heat transfer rate could be made using the test facility, a programme of development work followed in the course of which three different designs of condensing plate were evaluated in turn. The version eventually used in the main programme of experiments which followed was made from copper. However, its surfaces were coated with a thin layer of nickel and then with one of chromium. It was found that such a surface consistently promoted dropwise condensation and showed no signs of deterioration after lengthy periods of use. The rate of heat removal from pure steam and from mixtures of steam and air in varying proportions was measured as a function of plate sub-cooling for a variety of plate orientations. (author)

Purification method for condensate

International Nuclear Information System (INIS)

Shimoda, Akiyoshi.

1996-01-01

Condensates generated in secondary coolant circuits of a PWR type reactor are filtered using a hollow thread separation membranes comprising aromatic polyether ketone. Preferably, condensates after passing through a turbine are filtered at a place between a condensator and a steam generator at high temperature as close as a temperature of the steam generator. As the hollow thread membrane, partially crystalline membrane comprising aromatic polyether ketone is used. When it is used at high temperature, the crystallinity is preferably not less than 15wt%. Since a hollow thread membrane comprising the aromatic polyether ketone of excellent heat resistance is used, it can filter and purify the condensates at not lower than 70degC. Accordingly, impurities such as colloidal iron can be removed from the condensates, and the precipitation of cruds in the condensates to a steam generator and a turbine can be suppressed. (I.N.)

Optimal technique for deep breathing exercises after cardiac surgery.

Science.gov (United States)

Westerdahl, E

2015-06-01

Cardiac surgery patients often develop a restrictive pulmonary impairment and gas exchange abnormalities in the early postoperative period. Chest physiotherapy is routinely prescribed in order to reduce or prevent these complications. Besides early mobilization, positioning and shoulder girdle exercises, various breathing exercises have been implemented as a major component of postoperative care. A variety of deep breathing maneuvres are recommended to the spontaneously breathing patient to reduce atelectasis and to improve lung function in the early postoperative period. Different breathing exercises are recommended in different parts of the world, and there is no consensus about the most effective breathing technique after cardiac surgery. Arbitrary instructions are given, and recommendations on performance and duration vary between hospitals. Deep breathing exercises are a major part of this therapy, but scientific evidence for the efficacy has been lacking until recently, and there is a lack of trials describing how postoperative breathing exercises actually should be performed. The purpose of this review is to provide a brief overview of postoperative breathing exercises for patients undergoing cardiac surgery via sternotomy, and to discuss and suggest an optimal technique for the performance of deep breathing exercises.

Laboratory Scoping Tests Of Decontamination Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

Energy Technology Data Exchange (ETDEWEB)

Taylor-Pashow, Kathryn M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, Charles A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, William R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2014-01-21

compatible with longterm tank storage and immobilization methods. For this new application, testing is needed to demonstrate acceptable treatment sorbents and precipitating agents and measure decontamination factors for additional radionuclides in this unique waste stream. The origin of this LAW Off-Gas Condensate stream will be the liquids from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW melter off-gas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover. The soluble components are expected to be mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet and will not be available until the WTP begins operation, but a simulant has been produced based on models, calculations, and comparison with pilot-scale tests. One of the radionuclides that is volatile and expected to be in high concentration in this LAW Off-Gas Condensate stream is Technetium-99 (⁹⁹Tc). Technetium will not be removed from the aqueous waste in the Hanford WTP, and will primarily end up immobilized in the LAW glass by repeated recycle of the off-gas condensate into the LAW melter. Other radionuclides that are also expected to be in appreciable concentration in the LAW Off-Gas Condensate are ¹²⁹I, ⁹⁰Sr, ¹³⁷Cs, and {sup 241}Am. This report discusses results of preliminary radionuclide decontamination testing of the simulant. Testing examined use of Monosodium Titanate (MST) to remove ⁹⁰Sr and actinides, inorganic reducing agents for ⁹⁹Tc, and zeolites for ¹³⁷Cs. Test results indicate that excellent removal of ⁹⁹Tc was achieved using Sn(II)Cl₂ as a reductant, coupled with sorption onto hydroxyapatite, even in the presence of air and at room temperature. This process was very effective at neutral pH, with a Decontamination

Simple Simulations of DNA Condensation

Energy Technology Data Exchange (ETDEWEB)

STEVENS,MARK J.

2000-07-12

Molecular dynamics simulations of a simple, bead-spring model of semiflexible polyelectrolytes such as DNA are performed. All charges are explicitly treated. Starting from extended, noncondensed conformations, condensed structures form in the simulations with tetravalent or trivalent counterions. No condensates form or are stable for divalent counterions. The mechanism by which condensates form is described. Briefly, condensation occurs because electrostatic interactions dominate entropy, and the favored Coulombic structure is a charge ordered state. Condensation is a generic phenomena and occurs for a variety of polyelectrolyte parameters. Toroids and rods are the condensate structures. Toroids form preferentially when the molecular stiffness is sufficiently strong.

Breathing and Singing: Objective Characterization of Breathing Patterns in Classical Singers.

Science.gov (United States)

Salomoni, Sauro; van den Hoorn, Wolbert; Hodges, Paul

2016-01-01

Singing involves distinct respiratory kinematics (i.e. movements of rib cage and abdomen) to quiet breathing because of different demands on the respiratory system. Professional classical singers often advocate for the advantages of an active control of the abdomen on singing performance. This is presumed to prevent shortening of the diaphragm, elevate the rib cage, and thus promote efficient generation of subglottal pressure during phonation. However, few studies have investigated these patterns quantitatively and inter-subject variability has hindered the identification of stereotypical patterns of respiratory kinematics. Here, seven professional classical singers and four untrained individuals were assessed during quiet breathing, and when singing both a standard song and a piece of choice. Several parameters were extracted from respiratory kinematics and airflow, and principal component analysis was used to identify typical patterns of respiratory kinematics. No group differences were observed during quiet breathing. During singing, both groups adapted to rhythmical constraints with decreased time of inspiration and increased peak airflow. In contrast to untrained individuals, classical singers used greater percentage of abdominal contribution to lung volume during singing and greater asynchrony between movements of rib cage and abdomen. Classical singers substantially altered the coordination of rib cage and abdomen during singing from that used for quiet breathing. Despite variations between participants, principal component analysis revealed consistent pre-phonatory inward movements of the abdominal wall during singing. This contrasted with untrained individuals, who demonstrated synchronous respiratory movements during all tasks. The inward abdominal movements observed in classical singers elevates intra-abdominal pressure and may increase the length and the pressure-generating capacity of rib cage expiratory muscles for potential improvements in voice

21 CFR 862.3080 - Breath nitric oxide test system.

Science.gov (United States)

2010-04-01

... Systems § 862.3080 Breath nitric oxide test system. (a) Identification. A breath nitric oxide test system... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breath nitric oxide test system. 862.3080 Section... fractional nitric oxide concentration in expired breath aids in evaluating an asthma patient's response to...

Off-line breath acetone analysis in critical illness.

Science.gov (United States)

Sturney, S C; Storer, M K; Shaw, G M; Shaw, D E; Epton, M J

2013-09-01

Analysis of breath acetone could be useful in the Intensive Care Unit (ICU) setting to monitor evidence of starvation and metabolic stress. The aims of this study were to examine the relationship between acetone concentrations in breath and blood in critical illness, to explore any changes in breath acetone concentration over time and correlate these with clinical features. Consecutive patients, ventilated on controlled modes in a mixed ICU, with stress hyperglycaemia requiring insulin therapy and/or new pulmonary infiltrates on chest radiograph were recruited. Once daily, triplicate end-tidal breath samples were collected and analysed off-line by selected ion flow tube mass spectrometry (SIFT-MS). Thirty-two patients were recruited (20 males), median age 61.5 years (range 26-85 years). The median breath acetone concentration of all samples was 853 ppb (range 162-11 375 ppb) collected over a median of 3 days (range 1-8). There was a trend towards a reduction in breath acetone concentration over time. Relationships were seen between breath acetone and arterial acetone (rs = 0.64, p acetone concentration over time corresponded to changes in arterial acetone concentration. Some patients remained ketotic despite insulin therapy and normal arterial glucose concentrations. This is the first study to look at breath acetone concentration in ICU patients for up to 8 days. Breath acetone concentration may be used as a surrogate for arterial acetone concentration, which may in future have a role in the modulation of insulin and feeding in critical illness.

Condensation and Wetting Dynamics on Micro/Nano-Structured Surfaces

Science.gov (United States)

Olceroglu, Emre

Because of their adjustable wetting characteristics, micro/nanostructured surfaces are attractive for the enhancement of phase-change heat transfer where liquid-solid-vapor interactions are important. Condensation, evaporation, and boiling processes are traditionally used in a variety of applications including water harvesting, desalination, industrial power generation, HVAC, and thermal management systems. Although they have been studied by numerous researchers, there is currently a lack of understanding of the underlying mechanisms by which structured surfaces improve heat transfer during phase-change. This PhD dissertation focuses on condensation onto engineered surfaces including fabrication aspect, the physics of phase-change, and the operational limitations of engineered surfaces. While superhydrophobic condensation has been shown to produce high heat transfer rates, several critical issues remain in the field. These include surface manufacturability, heat transfer coefficient measurement limitations at low heat fluxes, failure due to surface flooding at high supersaturations, insufficient modeling of droplet growth rates, and the inherent issues associated with maintenance of non-wetted surface structures. Each of these issues is investigated in this thesis, leading to several contributions to the field of condensation on engineered surfaces. A variety of engineered surfaces have been fabricated and characterized, including nanostructured and hierarchically-structured superhydrophobic surfaces. The Tobacco mosaic virus (TMV) is used here as a biological template for the fabrication of nickel nanostructures, which are subsequently functionalized to achieve superhydrophobicity. This technique is simple and sustainable, and requires no applied heat or external power, thus making it easily extendable to a variety of common heat transfer materials and complex geometries. To measure heat transfer rates during superhydrophobic condensation in the presence of non-condensable

Breath-to-breath variability of exhaled CO2 as a marker of lung dysmaturity in infancy.

Science.gov (United States)

Fouzas, Sotirios; Theodorakopoulos, Ilias; Delgado-Eckert, Edgar; Latzin, Philipp; Frey, Urs

2017-12-01

The concept of diffusional screening implies that breath-to-breath variations in CO 2 clearance, when related to the variability of breathing, may contain information on the quality and utilization of the available alveolar surface. We explored the validity of the above hypothesis in a cohort of young infants of comparable postmenstrual age but born at different stages of lung maturity, namely, in term-born infants ( n = 128), preterm-born infants without chronic lung disease of infancy (CLDI; n = 53), and preterm infants with moderate/severe CLDI ( n = 87). Exhaled CO 2 volume (V E,CO2 ) and concentration (F E,CO2 ) were determined by volumetric capnography, whereas their variance was assessed by linear and nonlinear variability metrics. The relationship between relative breath-to-breath change of V E,CO2 (ΔV E,CO2 ) and the corresponding change of tidal volume (ΔV T ) was also analyzed. Nonlinear F E,CO2 variability was lower in CLDI compared with term and non-CLDI preterm group ( P variability was attributed to the variability of V T ( r 2 = 0.749), whereas in term and healthy preterm infants this relationship was weaker ( r 2 = 0.507 and 0.630, respectively). The ΔV E,CO2 - ΔV T slope was less steep in the CLDI group (1.06 ± 0.07) compared with non-CLDI preterm (1.16 ± 0.07; P variability that can be quantified by nonlinear variability metrics and may reflect the degree of lung dysmaturity. In infants with moderate/severe chronic lung disease of infancy (CLDI), the variability of the exhaled CO 2 is mainly driven by the variability of breathing, whereas in term-born and healthy preterm infants this relationship is less strong. The slope of the relative CO 2 -to-volume change is less steep in CLDI infants, suggesting that dysmature lungs are less efficient in eliminating CO 2 under tidal breathing conditions.

Condensation shocks in high momentum two-phase flows in condensing injectors

International Nuclear Information System (INIS)

Anand, G.; Christensen, R.N.

1993-01-01

This study presents a phenomenological and mathematical model of condensation shocks in high momentum two-phase flows in condensing injectors. The characteristics of the shock were related to the mode of vapor bubble collapse. Using cavitation terminology, the bubble collapse can be classified as inertially controlled or thermally controlled. Inertial bubble collapse occurs rapidly whereas, a thermally controlled collapse results in a significantly longer collapse time. The interdependence between the bubble collapse mode and the momentum and pressure of the flow, was analyzed in this study. For low-temperature-high-velocity flows a steep pressure rise with complete condensation was obtained. For a high-temperature-low velocity flow with noncondensables, low pressure recovery with incomplete condensation was observed. These trends are in agreement with previous experimental observations

Condensation in complex geometries

International Nuclear Information System (INIS)

Lauro, F.

1975-01-01

A mathematical evaluation of the condensation exchange coefficient can only succeds for well specified cases: small upright or inclined plates, horizontal tubes, small height vertical tubes. Among the main hypotheses accounted for this mathematical development in the case of the condensate, a laminar flow and uniform surface temperature are always considered. In practice certain shapes of surfaces significantly increase the heat transfer during the vapor condensation on a surface wet by the condensate. Such surfaces are rough surfaces such as the condensate is submitted to surface tension effects, negligeable for plane or large curvature surfaces, and the nature of the material may play an important role (temperature gradients). Results from tests on tubes with special shapes, performed in France or out of France, are given [fr

Influence of Continuous Table Motion on Patient Breathing Patterns

International Nuclear Information System (INIS)

Wilbert, Juergen; Baier, Kurt; Richter, Anne; Herrmann, Christian; Ma Lei; Flentje, Michael; Guckenberger, Matthias

2010-01-01

Purpose: To investigate the influence of continuous table motion on patient breathing patterns for compensation of moving targets by a robotic treatment couch. Methods and Materials: Fifteen volunteers were placed on a robotic treatment couch, and the couch was moved on different breathing-correlated and -uncorrelated trajectories. External abdominal breathing motion of the patients was measured using an infrared camera system. The influence of table motion on breathing range and pattern was analyzed. Results: Continuous table motion was tolerated well by all test persons. Volunteers reacted differently to table motion. Four test persons showed no change of breathing range and pattern. Increased irregular breathing was observed in 4 patients; however, irregularity was not correlated with table motion. Only 4 test persons showed an increase in mean breathing amplitude of more than 2mm during motion of the couch. The mean cycle period decreased by more than 1 s for 2 test persons only. No abrupt changes in amplitude or cycle period could be observed. Conclusions: The observed small changes in breathing patterns support the application of motion compensation by a robotic treatment couch.

Sedimentary condensation and authigenesis

Science.gov (United States)

Föllmi, Karl

2016-04-01

Most marine authigenic minerals form in sediments, which are subjected to condensation. Condensation processes lead to the formation of well individualized, extremely thin ( 100ky), and which experienced authigenesis and the precipitation of glaucony, verdine, phosphate, iron and manganese oxyhydroxides, iron sulfide, carbonate and/or silica. They usually show complex internal stratigraphies, which result from an interplay of sediment accumulation, halts in sedimentation, sediment winnowing, erosion, reworking and bypass. They may include amalgamated faunas of different origin and age. Hardgrounds may be part of condensed beds and may embody strongly condensed beds by themselves. Sedimentary condensation is the result of a hydrodynamically active depositional regime, in which sediment accumulation, winnowing, erosion, reworking and bypass are processes, which alternate as a function of changes in the location and intensity of currents, and/or as the result of episodic high-energy events engendered by storms and gravity flow. Sedimentary condensation has been and still is a widespread phenomenon in past and present-day oceans. The present-day distribution of glaucony and verdine-rich sediments on shelves and upper slopes, phosphate-rich sediments and phosphorite on outer shelves and upper slopes, ferromanganese crusts on slopes, seamounts and submarine plateaus, and ferromanganese nodules on abyssal seafloors is a good indication of the importance of condensation processes today. In the past, we may add the occurrence of oolitic ironstone, carbonate hardgrounds, and eventually also silica layers in banded iron formations as indicators of the importance of condensation processes. Besides their economic value, condensed sediments are useful both as a carrier of geochemical proxies of paleoceanographic and paleoenvironmental change, as well as the product of episodes of paleoceanographic and paleoenvironmental change themselves.

Optimization of sampling parameters for standardized exhaled breath sampling.

Science.gov (United States)

Doran, Sophie; Romano, Andrea; Hanna, George B

2017-09-05

The lack of standardization of breath sampling is a major contributing factor to the poor repeatability of results and hence represents a barrier to the adoption of breath tests in clinical practice. On-line and bag breath sampling have advantages but do not suit multicentre clinical studies whereas storage and robust transport are essential for the conduct of wide-scale studies. Several devices have been developed to control sampling parameters and to concentrate volatile organic compounds (VOCs) onto thermal desorption (TD) tubes and subsequently transport those tubes for laboratory analysis. We conducted three experiments to investigate (i) the fraction of breath sampled (whole vs. lower expiratory exhaled breath); (ii) breath sample volume (125, 250, 500 and 1000ml) and (iii) breath sample flow rate (400, 200, 100 and 50 ml/min). The target VOCs were acetone and potential volatile biomarkers for oesophago-gastric cancer belonging to the aldehyde, fatty acids and phenol chemical classes. We also examined the collection execution time and the impact of environmental contamination. The experiments showed that the use of exhaled breath-sampling devices requires the selection of optimum sampling parameters. The increase in sample volume has improved the levels of VOCs detected. However, the influence of the fraction of exhaled breath and the flow rate depends on the target VOCs measured. The concentration of potential volatile biomarkers for oesophago-gastric cancer was not significantly different between the whole and lower airway exhaled breath. While the recovery of phenols and acetone from TD tubes was lower when breath sampling was performed at a higher flow rate, other VOCs were not affected. A dedicated 'clean air supply' overcomes the contamination from ambient air, but the breath collection device itself can be a source of contaminants. In clinical studies using VOCs to diagnose gastro-oesophageal cancer, the optimum parameters are 500mls sample volume

Patient's breath controls comfort devices

Science.gov (United States)

Schrader, M.; Carpenter, B.; Nichols, C. D.

1972-01-01

Patient assist system for totally disabled persons was developed which permits a person, so paralyzed as to be unable to move, to activate by breathing, a call system to summon assistance, turn the page of a book, ajust his bed, or do any one of a number of other things. System consists of patient assist control and breath actuated switch.

A fibre-optic oxygen sensor for monitoring human breathing

International Nuclear Information System (INIS)

Chen, Rongsheng; Formenti, Federico; Hahn, Clive E W; Farmery, Andrew D; Obeid, Andy

2013-01-01

The development and construction of a tapered-tip fibre-optic fluorescence based oxygen sensor is described. The sensor is suitable for fast and real-time monitoring of human breathing. The sensitivity and response time of the oxygen sensor were evaluated in vitro with a gas pressure chamber system, where oxygen partial pressure was rapidly changed between 5 and 15 kPa, and then in vivo in five healthy adult participants who synchronized their breathing to a metronome set at 10, 20, 30, 40, 50, and 60 breaths min –1 . A Datex Ultima medical gas analyser was used to monitor breathing rate as a comparator. The sensor's response time in vitro was less than 150 ms, which allows accurate continuous measurement of inspired and expired oxygen pressure. Measurements of breathing rate by means of our oxygen sensor and of the Datex Ultima were in strong agreement. The results demonstrate that the device can reliably resolve breathing rates up to 60 breaths min –1 , and that it is a suitable cost-effective alternative for monitoring breathing rates and end-tidal oxygen partial pressure in the clinical setting. The rapid response time of the sensor may allow its use for monitoring rapid breathing rates as occur in children and the newborn. (note)

Imposed Work of Breathing for Flow Meters with In-Line versus Flow-Through Technique during Simulated Neonatal Breathing.

Science.gov (United States)

Donaldsson, Snorri; Falk, Markus; Jonsson, Baldvin; Drevhammar, Thomas

2015-01-01

The ability to determine airflow during nasal CPAP (NCPAP) treatment without adding dead space or resistance would be useful when investigating the physiologic effects of different NCPAP systems on breathing. The aim of this study was to investigate the effect on pressure stability of different flow measuring devices at the in-line and flow-through position, using simulated neonatal breathing. Six different flow measure devices were evaluated by recording pressure changes and imposed work of breathing for breaths with 16 and 32 ml tidal volumes. The tests were performed initially with the devices in an in line position and with 5 and 10 L/min using flow through technique, without CPAP. The flow meters were then subsequently tested with an Infant Flow CPAP system at 3, 5 and 8 cm H2O pressure using flow through technique. The quality of the recorded signals was compared graphically. The resistance of the measuring devices generated pressure swings and imposed work of breathing. With bias flow, the resistance also generated CPAP pressure. Three of the devices had low resistance and generated no changes in pressure stability or CPAP pressure. The two devices intended for neonatal use had the highest measured resistance. The importance of pressure stability and increased work of breathing during non-invasive respiratory support are insufficiently studied. Clinical trials using flow-through technique have not focused on pressure stability. Our results indicate that a flow-through technique might be a way forward in obtaining a sufficiently high signal quality without the added effects of rebreathing and increased work of breathing. The results should stimulate further research and the development of equipment for dynamic flow measurements in neonates.

The effect of CO2 on ventilation and breath-holding during exercise and while breathing through an added resistance.

Science.gov (United States)

Clark, T J; Godfrey, S

1969-05-01

1. Ventilation was measured while subjects were made to rebreathe from a bag containing CO(2) and O(2) in order to expose them to a steadily rising CO(2) tension (P(CO2)). The object of the experiments was to determine the effect of a variety of stimuli upon the increase in ventilation and fall in breath-holding time which occurs in response to the rising P(CO2).2. Steady-state exercise at 200 kg.m/min resulted in a small fall in the slope of the ventilation-CO(2) response curve (S(V)) and a small, though not statistically significant, fall in the P(CO2) at which ventilation would be zero by extrapolation (B(V)). There was a marked fall in the slope of the breath-holding-CO(2) response curve (S(BH)) and an increase in the P(CO2) at which breath-holding time became zero by extrapolation (B(BH)).3. These results have been interpreted with the aid of a model of the control of breath-holding and it is suggested that there is no change in CO(2) sensitivity on exercise, either during rebreathing or breath-holding.4. An increase in the resistance to breathing caused a marked reduction in S(V) and B(V), but no change in the breath-holding-CO(2) response curve. These findings suggest that the flattening of the ventilation-CO(2) response curve is mechanical in origin and acute airway obstruction produces no change in CO(2) sensitivity.5. On the basis of these results, we suggest that more information about CO(2) sensitivity can be obtained by a combination of ventilation and breath-holding-CO(2) response curves.

Possibility of removing condensate and scattered oil from gas-condensate field during bed flooding

Energy Technology Data Exchange (ETDEWEB)

Belkina, N.A.; Yagubov, M.S.

1984-01-01

The problem is set of evaluating the possible removal from the bed of scattered oil and condensate during flooding of the bed. For this purpose, an experimental study was made of the displacement by water from the porous medium of the oil and condensate saturating it. The obtained experimental results permit evaluation of the possible removal from the gas-condensate bed of scattered oil and condensate during flooding of the bed.

21 CFR 862.3050 - Breath-alcohol test system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breath-alcohol test system. 862.3050 Section 862.3050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....3050 Breath-alcohol test system. (a) Identification. A breath-alcohol test system is a device intened...

Research progress of control of condensate depression for condenser

Science.gov (United States)

Liu, Ying; Liang, Run; Li, Fengyu

2017-08-01

It is introduced that significance and structure of the condensate depression control system. In accordance with controller devised procedure, we analyze and elaborate how to construct the lumped parameter and dynamic mathematical model which possesses distinct physics significance. Neural network model being called black-box model is also introduced. We analyze and contrast the control technique of condensate depression as conventional PI control, fuzzy PI control and fuzzy control. It is indicated that if the controller of condensate depression were devised inappropriate, while the steam discharged of turbine varying by a large margin, would result in the rotation rate of cooling water circulating pump accelerating at a great lick even to trigger the galloping danger which is less impressive for the units operating safely.

Clinical Applications of CO2 and H2 Breath Test

Directory of Open Access Journals (Sweden)

ZHAO Si-qian;CHEN Bao-jun;LUO Zhi-fu

2016-08-01

Full Text Available Breath test is non-invasive, high sensitivity and high specificity. In this article, CO2 breath test, H2 breath test and their clinical applications were elaborated. The main applications of CO2 breath test include helicobacter pylori test, liver function detection, gastric emptying test, insulin resistance test, pancreatic exocrine secretion test, etc. H2 breath test can be applied in the diagnosis of lactose malabsorption and detecting small intestinal bacterial overgrowth. With further research, the breath test is expected to be applied in more diseases diagnosis.

Afternoon serum-melatonin in sleep disordered breathing.

Science.gov (United States)

Ulfberg, J; Micic, S; Strøm, J

1998-08-01

To study afternoon serum-melatonin values in patients with sleep disordered breathing. Melatonin has a strong circadian rhythm with high values during the night-time and low values in the afternoon. Sleep disordered breathing may change the circadian rhythm of melatonin which may have diagnostic implications. The Sleep Laboratory, The Department of Internal Medicine, Avesta Hospital, Sweden, and the Department of Anaesthesiology, Glostrup University Hospital, Copenhagen, Denmark. We examined 60 consecutive patients admitted for sleep disordered breathing and 10 healthy non snoring controls. The patients underwent a sleep apnoea screening test having a specificity of 100% for the obstructive sleep apnoea syndrome (OSAS) using a combination of static charge sensitive bed and oximetry. Obstructive sleep apnoea syndrome was found in 49 patients, eight patients had borderline sleep disordered breathing (BSDB) and three patients were excluded due to interfering disease. Patients and controls had an afternoon determination of serum-melatonin. The Epworth Sleepiness Scale was used to score day-time sleepiness. In comparison with normal controls patients suffering from OSAS had significantly higher serum-melatonin levels in the afternoon. However, as a diagnostic test for OSAS in patients with sleep disordered breathing serum-melatonin showed a low sensitivity but a high specificity. The results indicate that breathing disorders during sleep in general affect pineal function. Sleep disordered breathing seems to disturb pineal function. Determination of afternoon serum-melatonin alone or together with a scoring of daytime sleepiness does not identify OSAS-patients in a heterogeneous population of patients complaining of heavy snoring and excessive daytime sleepiness.

An Ultrasonic Contactless Sensor for Breathing Monitoring

Directory of Open Access Journals (Sweden)

Philippe Arlotto

2014-08-01

Full Text Available The monitoring of human breathing activity during a long period has multiple fundamental applications in medicine. In breathing sleep disorders such as apnea, the diagnosis is based on events during which the person stops breathing for several periods during sleep. In polysomnography, the standard for sleep disordered breathing analysis, chest movement and airflow are used to monitor the respiratory activity. However, this method has serious drawbacks. Indeed, as the subject should sleep overnight in a laboratory and because of sensors being in direct contact with him, artifacts modifying sleep quality are often observed. This work investigates an analysis of the viability of an ultrasonic device to quantify the breathing activity, without contact and without any perception by the subject. Based on a low power ultrasonic active source and transducer, the device measures the frequency shift produced by the velocity difference between the exhaled air flow and the ambient environment, i.e., the Doppler effect. After acquisition and digitization, a specific signal processing is applied to separate the effects of breath from those due to subject movements from the Doppler signal. The distance between the source and the sensor, about 50 cm, and the use of ultrasound frequency well above audible frequencies, 40 kHz, allow monitoring the breathing activity without any perception by the subject, and therefore without any modification of the sleep quality which is very important for sleep disorders diagnostic applications. This work is patented (patent pending 2013-7-31 number FR.13/57569.

Universal Themes of Bose-Einstein Condensation

Science.gov (United States)

Proukakis, Nick P.; Snoke, David W.; Littlewood, Peter B.

2017-04-01

Foreword; List of contributors; Preface; Part I. Introduction: 1. Universality and Bose-Einstein condensation: perspectives on recent work D. W. Snoke, N. P. Proukakis, T. Giamarchi and P. B. Littlewood; 2. A history of Bose-Einstein condensation of atomic hydrogen T. Greytak and D. Kleppner; 3. Twenty years of atomic quantum gases: 1995-2015 W. Ketterle; 4. Introduction to polariton condensation P. B. Littlewood and A. Edelman; Part II. General Topics: Editorial notes; 5. The question of spontaneous symmetry breaking in condensates D. W. Snoke and A. J. Daley; 6. Effects of interactions on Bose-Einstein condensation R. P. Smith; 7. Formation of Bose-Einstein condensates M. J. Davis, T. M. Wright, T. Gasenzer, S. A. Gardiner and N. P. Proukakis; 8. Quenches, relaxation and pre-thermalization in an isolated quantum system T. Langen and J. Schmiedmayer; 9. Ultracold gases with intrinsic scale invariance C. Chin; 10. Berezinskii-Kosterlitz-Thouless phase of a driven-dissipative condensate N. Y. Kim, W. H. Nitsche and Y. Yamamoto; 11. Superfluidity and phase correlations of driven dissipative condensates J. Keeling, L. M. Sieberer, E. Altman, L. Chen, S. Diehl and J. Toner; 12. BEC to BCS crossover from superconductors to polaritons A. Edelman and P. B. Littlewood; Part III. Condensates in Atomic Physics: Editorial notes; 13. Probing and controlling strongly correlated quantum many-body systems using ultracold quantum gases I. Bloch; 14. Preparing and probing chern bands with cold atoms N. Goldman, N. R. Cooper and J. Dalibard; 15. Bose-Einstein condensates in artificial gauge fields L. J. LeBlanc and I. B. Spielman; 16. Second sound in ultracold atomic gases L. Pitaevskii and S. Stringari; 17. Quantum turbulence in atomic Bose-Einstein condensates N. G. Parker, A. J. Allen, C. F. Barenghi and N. P. Proukakis; 18. Spinor-dipolar aspects of Bose-Einstein condensation M. Ueda; Part IV. Condensates in Condensed Matter Physics: Editorial notes; 19. Bose

Assessment of TRACE Condensation Model Against Reflux Condensation Tests with Noncondensable Gases

Energy Technology Data Exchange (ETDEWEB)

Lee, Kyung Won; Cheong, Ae Ju; Shin, Andong; Suh, Nam Duk [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2015-05-15

The TRACE is the latest in a series of advanced, best-estimated reactor systems code developed by U.S. Nuclear Regulatory Commission for analyzing transient and steady-state neutronic-thermal-hydraulic behavior in light water reactors. This special model is expected to replace the default model in a future code release after sufficient testing has been completed. This study assesses the special condensation model of TRACE 5.0-patch4 against the counter-current flow configuration. For this purpose, the predicted results of special model are compared to the experimental and to those of default model. The KAST reflux condensation test with NC gases are used in this assessment. We assessed the special model for film condensation of TRACE 5.0-patch4 against the data of the reflux condensation test in the presence of NC gases. The special condensation model of TRACE provides a reasonable estimate of HTC with good agreement at the low inlet steam flow rate.

Assessment of TRACE Condensation Model Against Reflux Condensation Tests with Noncondensable Gases

International Nuclear Information System (INIS)

Lee, Kyung Won; Cheong, Ae Ju; Shin, Andong; Suh, Nam Duk

2015-01-01

The TRACE is the latest in a series of advanced, best-estimated reactor systems code developed by U.S. Nuclear Regulatory Commission for analyzing transient and steady-state neutronic-thermal-hydraulic behavior in light water reactors. This special model is expected to replace the default model in a future code release after sufficient testing has been completed. This study assesses the special condensation model of TRACE 5.0-patch4 against the counter-current flow configuration. For this purpose, the predicted results of special model are compared to the experimental and to those of default model. The KAST reflux condensation test with NC gases are used in this assessment. We assessed the special model for film condensation of TRACE 5.0-patch4 against the data of the reflux condensation test in the presence of NC gases. The special condensation model of TRACE provides a reasonable estimate of HTC with good agreement at the low inlet steam flow rate

Advantage of using deep inspiration breath hold with active breathing control and image-guided radiation therapy for patients treated with lung cancers

International Nuclear Information System (INIS)

Muralidhar, K.R.; Madhusudhansresty; Sha, Rajib Lochan; Raut, Birendra Kumar; Poornima; Subash; Mallikarjun; Anil; Krishnam Raju, A.; Vidya; Sudarshan, G.; Mahadev, Shankar; Narayana Murthy, P.

2008-01-01

To evaluate the impact of moderate deep inspiration breath hold (mDIBH) using an active breathing control (ABC) apparatus on heart, spinal cord, liver and contra lateral lung doses and its volumes compared with free breathing (FB) with lung cancer irradiation

Predictive value of 14CO2 breath tests for clinical use of 13CO2 breath tests

International Nuclear Information System (INIS)

Glaubitt, D.M.H.

1975-01-01

The knowledge of the efficiency of 14 CO 2 breath tests makes possible the comparison of the efficiency of analogous tests using the stable isotope 13 C. 14 CO 2 exhalation studies render overall information. After parenteral administration of a 14 C labeled substrate, 14 CO 2 breath tests permit insight into the metabolism of the 14 C substrate and the associated intermediary metabolism. If the 14 C substrate is given orally or by intraduodenal instillation, 14 CO 2 breath tests supply information not only about gastrointenstinal absorption and digestion but also about the intermediary metabolism yielding 14 CO 2 , after the administered substrate or its degradation products have been absorbed in the gastrointestinal tract. The fraction of 14 CO 2 arising from absorption, digestion and intermediary metabolism can be estimated only by additional methods. 14 CO 2 breath tests are unable to delineate single metabolic reactions involved in the formation of carbon dioxide. Under these considerations the clinical application of 14 CO 2 breath tests may provide diagnostically useful results, especially in internal medicine and surgery. The tests are suitable for intraindividual assessment of the course of a disease and of therapeutic effects. They may be important in the research of the metabolism of 14 C labeled substrates

Implementation of non-condensable gases condensation suppression model into the WCOBRA/TRAC-TF2 LOCA safety evaluation code

Energy Technology Data Exchange (ETDEWEB)

Liao, J.; Cao, L.; Ohkawa, K.; Frepoli, C. [LOCA Integrated Services I, Westinghouse Electric Company, 1000 Westinghouse Drive, Cranberry Township, PA 16066 (United States)

2012-07-01

The non-condensable gases condensation suppression model is important for a realistic LOCA safety analysis code. A condensation suppression model for direct contact condensation was previously developed by Westinghouse using first principles. The model is believed to be an accurate description of the direct contact condensation process in the presence of non-condensable gases. The Westinghouse condensation suppression model is further revised by applying a more physical model. The revised condensation suppression model is thus implemented into the WCOBRA/TRAC-TF2 LOCA safety evaluation code for both 3-D module (COBRA-TF) and 1-D module (TRAC-PF1). Parametric study using the revised Westinghouse condensation suppression model is conducted. Additionally, the performance of non-condensable gases condensation suppression model is examined in the ACHILLES (ISP-25) separate effects test and LOFT L2-5 (ISP-13) integral effects test. (authors)

Oral breathing and speech disorders in children

Directory of Open Access Journals (Sweden)

Silvia F. Hitos

2013-07-01

Conclusion: Mouth breathing can affect speech development, socialization, and school performance. Early detection of mouth breathing is essential to prevent and minimize its negative effects on the overall development of individuals.

Bad-breath: Perceptions and misconceptions of Nigerian adults.

Science.gov (United States)

Nwhator, S O; Isiekwe, G I; Soroye, M O; Agbaje, M O

2015-01-01

To provide baseline data about bad-breath perception and misconceptions among Nigerian adults. Multi-center cross-sectional study of individuals aged 18-64 years using examiner-administered questionnaires. Age comparisons were based on the model of emerging adults versus full adults. Data were recoded for statistical analyses and univariate and secondary log-linear statistics applied. Participants had lopsided perceptions about bad-breath. While 730 (90.8%) identified the dentist as the expert on halitosis and 719 (89.4%) knew that bad-breath is not contagious, only 4.4% and 2.5% associated bad-breath with tooth decay and gum disease respectively. There were no significant sex differences but the older adults showed better knowledge in a few instances. Most respondents (747, 92.9%) would tell a spouse about their bad-breath and 683 (85%) would tell a friend. Participants had lop-sided knowledge and perceptions about bad-breath. Most Nigerian adults are their "brothers' keepers" who would tell a spouse or friend about their halitosis so they could seek treatment.

The effect of mouth breathing on chewing efficiency.

Science.gov (United States)

Nagaiwa, Miho; Gunjigake, Kaori; Yamaguchi, Kazunori

2016-03-01

To examine the effect of mouth breathing on chewing efficiency by evaluating masticatory variables. Ten adult nasal breathers with normal occlusion and no temporomandibular dysfunction were selected. Subjects were instructed to bite the chewing gum on the habitual side. While breathing through the mouth and nose, the glucide elution from the chewing gum, number of chewing strokes, duration of chewing, and electromyography (EMG) activity of the masseter muscle were evaluated as variables of masticatory efficiency. The durations required for the chewing of 30, 60, 90, 120, 180, and 250 strokes were significantly (P chewing stroke between nose and mouth breathings. The glucide elution rates for 1- and 3-minute chewing were significantly (P chewing between nose and mouth breathings. While chewing for 1, 3, and 5 minutes, the chewing stroke and EMG activity of the masseter muscle were significantly (P chewing to obtain higher masticatory efficiency when breathing through the mouth. Therefore, mouth breathing will decrease the masticatory efficiency if the duration of chewing is restricted in everyday life.

Effect of flow velocity on the process of air-steam condensation in a vertical tube condenser

Science.gov (United States)

Havlík, Jan; Dlouhý, Tomáš

2018-06-01

This article describes the influence of flow velocity on the condensation process in a vertical tube. For the case of condensation in a vertical tube condenser, both the pure steam condensation process and the air-steam mixture condensation process were theoretically and experimentally analyzed. The influence of steam flow velocity on the value of the heat transfer coefficient during the condensation process was evaluated. For the condensation of pure steam, the influence of flow velocity on the value of the heat transfer coefficient begins to be seen at higher speeds, conversely, this effect is negligible at low values of steam velocity. On the other hand, for the air-steam mixture condensation, the influence of flow velocity must always be taken into account. The flow velocity affects the water vapor diffusion process through non-condensing air. The presence of air significantly reduces the value of the heat transfer coefficient. This drop in the heat transfer coefficient is significant at low velocities; on the contrary, the decrease is relatively small at high values of the velocity.

Performance of casting aluminum-silicon alloy condensing heating exchanger for gas-fired boiler

Science.gov (United States)

Cao, Weixue; Liu, Fengguo; You, Xue-yi

2018-01-01

Condensing gas boilers are widely used due to their high heat efficiency, which comes from their ability to use the recoverable sensible heat and latent heat in flue gas. The condensed water of the boiler exhaust has strong corrosion effect on the heat exchanger, which restricts the further application of the condensing gas boiler. In recent years, a casting aluminum-silicon alloy (CASA), which boasts good anti-corrosion properties, has been introduced to condensing hot water boilers. In this paper, the heat transfer performance, CO and NOx emission concentrations and CASA corrosion resistance of a heat exchanger are studied by an efficiency bench test of the gas-fired boiler. The experimental results are compared with heat exchangers produced by Honeywell and Beka. The results show that the excess air coefficient has a significant effect on the heat efficiency and CO and NOx emission of the CASA water heater. When the excess air coefficient of the CASA gas boiler is 1.3, the CO and NOx emission concentration of the flue gas satisfies the design requirements, and the heat efficiency of water heater is 90.8%. In addition, with the increase of heat load rate, the heat transfer coefficient of the heat exchanger and the heat efficiency of the water heater are increased. However, when the heat load rate is at 90%, the NOx emission in the exhaust gas is the highest. Furthermore, when the temperature of flue gas is below 57 °C, the condensation of water vapor occurs, and the pH of condensed water is in the 2.5 5.5 range. The study shows that CASA water heater has good corrosion resistance and a high heat efficiency of 88%. Compared with the heat exchangers produced by Honeywell and Beka, there is still much work to do in optimizing and improving the water heater.

Imposed Work of Breathing for Flow Meters with In-Line versus Flow-Through Technique during Simulated Neonatal Breathing.

Directory of Open Access Journals (Sweden)

Snorri Donaldsson

Full Text Available The ability to determine airflow during nasal CPAP (NCPAP treatment without adding dead space or resistance would be useful when investigating the physiologic effects of different NCPAP systems on breathing. The aim of this study was to investigate the effect on pressure stability of different flow measuring devices at the in-line and flow-through position, using simulated neonatal breathing.Six different flow measure devices were evaluated by recording pressure changes and imposed work of breathing for breaths with 16 and 32 ml tidal volumes. The tests were performed initially with the devices in an in line position and with 5 and 10 L/min using flow through technique, without CPAP. The flow meters were then subsequently tested with an Infant Flow CPAP system at 3, 5 and 8 cm H2O pressure using flow through technique. The quality of the recorded signals was compared graphically.The resistance of the measuring devices generated pressure swings and imposed work of breathing. With bias flow, the resistance also generated CPAP pressure. Three of the devices had low resistance and generated no changes in pressure stability or CPAP pressure. The two devices intended for neonatal use had the highest measured resistance.The importance of pressure stability and increased work of breathing during non-invasive respiratory support are insufficiently studied. Clinical trials using flow-through technique have not focused on pressure stability. Our results indicate that a flow-through technique might be a way forward in obtaining a sufficiently high signal quality without the added effects of rebreathing and increased work of breathing. The results should stimulate further research and the development of equipment for dynamic flow measurements in neonates.

Condensation: the new deal; Condensation: la nouvelle donne

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-06-01

The principle of condensation boilers is based on the recovery of the latent heat of the steam generated by the combustion of natural gas. This technology was introduced in France at the end of the 80's but failed in its promise because of the complexity of the equipments available at that time. Today, constructors' offer is more mature and reliable and the context has changed. This technology can conciliate three goals: a mastery of energy consumptions, the comfort of the user and the respect of environment. This meeting organized by the research center of Gaz de France (Cegibat), was a good opportunity to makes a status of the market of individual condensation systems in France and in Europe, to present the situation of this technology today and the 10 golden rules for the fitting and maintenance of individual condensation boilers, and to present some technical references, examples and results of today's offer. (J.S.)

Breathing pattern and head posture: changes in craniocervical angles.

Science.gov (United States)

Sabatucci, A; Raffaeli, F; Mastrovincenzo, M; Luchetta, A; Giannone, A; Ciavarella, D

2015-04-01

The aim of this study was to observe the influence of oral breathing on head posture and to establish possible postural changes observing the variation of craniocervical angles NSL/OPT and NSL/CVT between oral breathing subjects and physiological breathing subjects. A cross-sectional study was conducted. The sample included 115 subject, 56 boys and 59 girls, 5-22-year-old. Among these, 80 were classified as oral breathers and 35 as physiological breathers. The diagnosis of oral breathing was carried out thanks to characteristic signs and symptoms evaluated on clinical examination, the analysis of characteristic X-ray images, ENT examination with active anterior rhinomanometric (AAR) test. The structural and postural analysis was carried out, calculating the craniofacial angles NSL/OPT and NSL/CVT. Both NSL/OPT and NSL/CVT appear to be significantly greater to those observed in physiological breathing patients. This means that patients who tend to breathe through the mouth rather than exclusively through the nose show a reduction of cervical lordosis and a proinclination of the head. Our study confirms that the oral breathing modifies head position. The significant increase of the craniocervical angles NSL/OPT and NSL/CVT in patients with this altered breathing pattern suggests an elevation of the head and a greater extension of the head compared with the cervical spine. So, to correct the breathing pattern early, either during childhood or during adolescence, can lead to a progressive normalization of craniofacial morphology and head posture.

Ph3CCOOSnPh3.Ph3PO AND Ph3CCOOSnPh3.Ph3AsO: SYNTHESIS AND INFRARED STUDY

Directory of Open Access Journals (Sweden)

ABDOU MBAYE

2014-08-01

Full Text Available The mixture of ethanolic solutions of Ph3CCOOSnPh3 and Ph3PO or Ph3AsO gives Ph3CCOOSnPh3.Ph3PO and Ph3CCOOSnPh3.Ph3AsO adducts which have been characterized by infrared spectroscopy. A discrete structure is suggested for both, the environment around the tin centre being trigonal bipyramidal, the triphenylacetate anion behaving as a mondentate ligand.

Sensing the effects of mouth breathing by using 3-tesla MRI

Science.gov (United States)

Park, Chan-A.; Kang, Chang-Ki

2017-06-01

We investigated the effects of mouth breathing and typical nasal breathing on brain function by using blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging (fMRI). The study had two parts: the first test was a simple contrast between mouth and nasal breathing, and the second test involved combined breathing modes, e.g., mouth inspiration and nasal expiration. Eleven healthy participants performed the combined breathing task while undergoing 3T fMRI. In the group-level analysis, contrast images acquired by using an individual participantlevel analysis were processed using the one-sample t test. We also conducted a region-of-interest analysis comparing signal intensity changes between the breathing modes; the region was selected using an automated anatomical labeling map. The results demonstrated that the BOLD signal in the hippocampus and brainstem was significantly decreased in mouth breathing relative to nasal breathing. On the other hand, both the precentral and postcentral gyri showed activation that was more significant in mouth breathing compared to nasal breathing. This study suggests that the BOLD activity patterns between mouth and nasal breathing may be induced differently, especially in the hippocampus, which could provide clues to explain the effects on brain cognitive function due to mouth breathing.

ACTIVE CYCLE BREATHING TECHNIQUES IN HEART FAILURE ...

African Journals Online (AJOL)

RICHY

Pulmonary Function Responses to Active Cycle. Breathing ... Key Words: Heart Failure, Active Cycle of Breathing ... cough, fatigue, reduced respiratory muscle mass, and. [5] ... an amount of exercise which is said to lower disease. [9].

Blue breath holding is benign.

OpenAIRE

Stephenson, J B

1991-01-01

In their recent publication in this journal, Southall et al described typical cyanotic breath holding spells, both in otherwise healthy children and in those with brainstem lesions and other malformations. Their suggestions regarding possible autonomic disturbances may require further study, but they have adduced no scientific evidence to contradict the accepted view that in the intact child blue breath holding spells are benign. Those families in which an infant suffers an 'apparently life t...

Born-Kothari Condensation for Fermions

Directory of Open Access Journals (Sweden)

Arnab Ghosh

2017-09-01

Full Text Available In the spirit of Bose–Einstein condensation, we present a detailed account of the statistical description of the condensation phenomena for a Fermi–Dirac gas following the works of Born and Kothari. For bosons, while the condensed phase below a certain critical temperature, permits macroscopic occupation at the lowest energy single particle state, for fermions, due to Pauli exclusion principle, the condensed phase occurs only in the form of a single occupancy dense modes at the highest energy state. In spite of these rudimentary differences, our recent findings [Ghosh and Ray, 2017] identify the foregoing phenomenon as condensation-like coherence among fermions in an analogous way to Bose–Einstein condensate which is collectively described by a coherent matter wave. To reach the above conclusion, we employ the close relationship between the statistical methods of bosonic and fermionic fields pioneered by Cahill and Glauber. In addition to our previous results, we described in this mini-review that the highest momentum (energy for individual fermions, prerequisite for the condensation process, can be specified in terms of the natural length and energy scales of the problem. The existence of such condensed phases, which are of obvious significance in the context of elementary particles, have also been scrutinized.

Condensation in Nanoporous Packed Beds.

Science.gov (United States)

Ally, Javed; Molla, Shahnawaz; Mostowfi, Farshid

2016-05-10

In materials with tiny, nanometer-scale pores, liquid condensation is shifted from the bulk saturation pressure observed at larger scales. This effect is called capillary condensation and can block pores, which has major consequences in hydrocarbon production, as well as in fuel cells, catalysis, and powder adhesion. In this study, high pressure nanofluidic condensation studies are performed using propane and carbon dioxide in a colloidal crystal packed bed. Direct visualization allows the extent of condensation to be observed, as well as inference of the pore geometry from Bragg diffraction. We show experimentally that capillary condensation depends on pore geometry and wettability because these factors determine the shape of the menisci that coalesce when pore filling occurs, contrary to the typical assumption that all pore structures can be modeled as cylindrical and perfectly wetting. We also observe capillary condensation at higher pressures than has been done previously, which is important because many applications involving this phenomenon occur well above atmospheric pressure, and there is little, if any, experimental validation of capillary condensation at such pressures, particularly with direct visualization.

Comparison of Heat Transfer Coefficients of Silver Coated and Chromium Coated Copper Tubes of Condenser in Dropwise Condensation

OpenAIRE

Er. Shivesh Kumar; Dr. Amit Kumar

2016-01-01

Since centuries steam is being used in power generating system. The steam leaving the power unit is reconverted into water in a condenser designed to transfer heat from the steam to the cooling water as rapidly and as efficiently as possible. The efficiency of condenser depends on rate of condensation and mode of condensation of steam in the condenser. The increase in efficiency of the condenser enhances the heat transfer co-efficient which in turn results in economic design of condenser and ...

Bio-oil fractionation and condensation

Science.gov (United States)

Brown, Robert C; Jones, Samuel T; Pollard, Anthony

2013-07-02

A method of fractionating bio-oil vapors which involves providing bio-oil vapors comprising bio-oil constituents is described. The bio-oil vapors are cooled in a first stage which comprises a condenser having passages for the bio-oil separated by a heat conducting wall from passages for a coolant. The coolant in the condenser of the first stage is maintained at a substantially constant temperature, set at a temperature in the range of 75 to 100.degree. C., to condense a first liquid fraction of liquefied bio-oil constituents in the condenser of the first stage. The first liquid fraction of liquified bio-oil constituents from the condenser in the first stage is collected. Also described are steps for subsequently recovering further liquid fractions of liquefied bio-oil constituents. Particular compositions of bio-oil condensation products are also described.

Condenser performance monitoring and cleaning

International Nuclear Information System (INIS)

Walden, J.V.

1998-01-01

The main condenser at Ginna Station was retubed from admiralty brass to 316 stainless steel. A condenser performance monitoring spreadsheet was developed using EPRI guidelines after fouling was discovered. PEPSE computer models were used to determine the power loss and confirm the spreadsheet results. Cleaning of the condenser was performed using plastic scrubbers. Condenser performance improved dramatically following the cleaning. PEPSE, condenser spreadsheet performance, and actual observed plant data correlated well together. The fouling mechanism was determined to be a common lake bacteria and fungus growth which was combined with silt. Chlorination of the circulating water system at the allowable limits is keeping the biofouling under control

Chromosome condensation and segmentation

International Nuclear Information System (INIS)

Viegas-Pequignot, E.M.

1981-01-01

Some aspects of chromosome condensation in mammalians -humans especially- were studied by means of cytogenetic techniques of chromosome banding. Two further approaches were adopted: a study of normal condensation as early as prophase, and an analysis of chromosome segmentation induced by physical (temperature and γ-rays) or chemical agents (base analogues, antibiotics, ...) in order to show out the factors liable to affect condensation. Here 'segmentation' means an abnormal chromosome condensation appearing systematically and being reproducible. The study of normal condensation was made possible by the development of a technique based on cell synchronization by thymidine and giving prophasic and prometaphasic cells. Besides, the possibility of inducing R-banding segmentations on these cells by BrdU (5-bromodeoxyuridine) allowed a much finer analysis of karyotypes. Another technique was developed using 5-ACR (5-azacytidine), it allowed to induce a segmentation similar to the one obtained using BrdU and identify heterochromatic areas rich in G-C bases pairs [fr

Characteristic aspects of pion-condensed phases

International Nuclear Information System (INIS)

Takatsuka, Tatsuyuki; Tamagaki, Ryozo; Tatsumi, Toshitaka.

1993-01-01

Characteristic aspects of pion-condensed phases are described in a simple model, for the system involving only nucleons and pions which interact through the π-N P-wave interaction. We consider one typical version in each of three kinds of pion condensation; the one of neutral pions (π 0 ), the one of charged pions (π C ) and the combined one in which both the π 0 and π C condensations are coexistent. Emphasis is put on the description to clarify the novel structures of the nucleon system which are realized in the pion-condensed phases. At first, it is shown that the π 0 condensation is equivalent to the particular nucleonic phase realized by a structure change of the nucleon system, where the attractive first-order effect of the one-pion-exchange (OPE) tensor force is brought about coherently. The aspects of this phase are characterized by the layered structure with a specific spin-isospin order with one-dimensional localization (named the ALS structure in short), which provides the source function for the condensed π 0 field. We utilize both descriptions with use of fields and potentials for the π 0 condensation. Next, the π C condensation realized in neutron-rich matter is described by adopting a version of the traveling condensed wave. In this phase, the nucleonic structure becomes the Fermi gas consisting of quasi-neutrons described by a superposition of neutron and proton. In this sense the structure change of the nucleon system for the π C condensation is moderate, and the field description is suitable. Finally, we describe a coexistent pion condensation, in which both the π 0 and π C condensations coexist without interference in such a manner that the π C condensation develops in the ALS structure. The model adopted here provides us with the characteristic aspects of the pion-condensed phases persisting in the realistic situation, where other ingredients affecting the pion condensation are taken into account. (author)

Systematic text condensation

DEFF Research Database (Denmark)

Malterud, Kirsti

2012-01-01

To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies.......To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies....

Aspiration tests in aqueous foam using a breathing simulator

Energy Technology Data Exchange (ETDEWEB)

Archuleta, M.M.

1995-12-01

Non-toxic aqueous foams are being developed by Sandia National Laboratories (SNL) for the National Institute of Justice (NIJ) for use in crowd control, cell extractions, and group disturbances in the criminal justice prison systems. The potential for aspiration of aqueous foam during its use and the resulting adverse effects associated with complete immersion in aqueous foam is of major concern to the NIJ when examining the effectiveness and safety of using this technology as a Less-Than-Lethal weapon. This preliminary study was designed to evaluate the maximum quantity of foam that might be aspirated by an individual following total immersion in an SNL-developed aqueous foam. A.T.W. Reed Breathing simulator equipped with a 622 Silverman cam was used to simulate the aspiration of an ammonium laureth sulfate aqueous foam developed by SNL and generated at expansion ratios in the range of 500:1 to 1000:1. Although the natural instinct of an individual immersed in foam is to cover their nose and mouth with a hand or cloth, thus breaking the bubbles and decreasing the potential for aspiration, this study was performed to examine a worst case scenario where mouth breathing only was examined, and no attempt was made to block foam entry into the breathing port. Two breathing rates were examined: one that simulated a sedentary individual with a mean breathing rate of 6.27 breaths/minute, and one that simulated an agitated or heavily breathing individual with a mean breathing rate of 23.7 breaths/minute. The results of this study indicate that, if breathing in aqueous foam without movement, an air pocket forms around the nose and mouth within one minute of immersion.

Practical recommendations for breathing-adapted radiotherapy

International Nuclear Information System (INIS)

Simon, L.; Giraud, P.; Rosenwald, J.C.; Dumas, J.L.; Lorchel, F.; Marre, D.; Dupont, S.; Varmenot, N.; Ginestet, C.; Caron, J.; Marchesi, V.; Ferreira, I.; Garcia, R.

2007-01-01

Respiration-gated radiotherapy offers a significant potential for improvement in the irradiation of tumor sites affected by respiratory motion such as lung, breast and liver tumors. An increased conformality of irradiation fields leading to decreased complications rates of organs at risk (lung, heart) is expected. Respiratory gating is in line with the need for improved precision required by radiotherapy techniques such as 3D conformal radiotherapy or intensity modulated radiotherapy. Reduction of respiratory motion can be achieved by using either breath-hold techniques or respiration synchronized gating techniques. Breath-hold techniques can be achieved with active techniques, in which airflow of the patient is temporarily blocked by a valve, or passive techniques, in which the patient voluntarily holds his/her breath. Synchronized gating techniques use external devices to predict the phase of the respiration cycle while the patient breaths freely. This work summarizes the different experiences of the centers of the STIC 2003 project. It describes the different techniques, gives an overview of the literature and proposes a practice based on our experience. (authors)

Breathing and Relaxation

Science.gov (United States)

... Find a Doctor Relaxation is the absence of tension in muscle groups and a minimum or absence ... Drill Meditation Progressive Muscle Relaxation Minimizing Shortness of Breath Visualization This information has been approved by Shelby ...

Shortness of Breath

Science.gov (United States)

... filled with air (called pneumotho- rax), it will hinder expansion of the lung, resulting in shortness of ... of Chest Physi- cians. Shortness of Breath: Patient Education. http: / / www. onebreath. org/ document. doc? id= 113. ...

Steam generators, turbines, and condensers. Volume six

International Nuclear Information System (INIS)

Anon.

1986-01-01

Volume six covers steam generators (How steam is generated, steam generation in a PWR, vertical U-tube steam generators, once-through steam generators, how much steam do steam generators make?), turbines (basic turbine principles, impulse turbines, reaction turbines, turbine stages, turbine arrangements, turbine steam flow, steam admission to turbines, turbine seals and supports, turbine oil system, generators), and condensers (need for condensers, basic condenser principles, condenser arrangements, heat transfer in condensers, air removal from condensers, circulating water system, heat loss to the circulating water system, factors affecting condenser performance, condenser auxiliaries)

How Does a Hopping Kangaroo Breathe?

Science.gov (United States)

Giuliodori, Mauricio J.; Lujan, Heidi L.; Janbaih, Hussein; DiCarlo, Stephen E.

2010-01-01

We developed a model to demonstrate how a hopping kangaroo breathes. Interestingly, a kangaroo uses less energy to breathe while hopping than while standing still. This occurs, in part, because rather than using muscle power to move air into and out of the lungs, air is pulled into (inspiration) and pushed out of (expiration) the lungs as the…

A CFD study of wave influence on film steam condensation in the presence of non-condensable gas

Energy Technology Data Exchange (ETDEWEB)

Wang, Xianmao, E-mail: xm-wang11@mails.tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Chang, Huajian, E-mail: changhj@tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Corradini, Michael, E-mail: corradini@engr.wisc.edu [Department of Engineering Physics, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, WI 53706 (United States)

2016-08-15

Highlights: • A condensation model is incorporated in the ANSYS FLUENT. • Different turbulence models are evaluated for flows over wavy surfaces. • Wavy surfaces with and without moving velocities are used to model the wave. • Various wavy surfaces with different wave heights and wavelengths are selected. • Wave influence on film steam condensation is investigated. - Abstract: Steam condensation plays an important role in removing heat from the containment of a nuclear plant during postulated accidents. However, due to the presence of non-condensable gases such as air and hydrogen in the containment, the condensation rate can decrease dramatically. Under certain conditions, the condensate film on the cold containment walls can affect the overall heat transfer rate. The wavy interface of the condensate film is a factor and is usually believed to enhance the condensation rate, since the waves can both increase the interfacial area and disturb the non-condensable gas boundary layer. However, it is not clear how to properly account for this factor and what is its quantitative influence in experiments. In this work, a CFD approach is applied to study the wave effects on film condensation in the presence of non-condensable gas. Wavy surfaces with and without moving velocities are used to replace the wavy interface of the falling film. A condensation model is incorporated in the ANSYS FLUENT simulation and a realizable k–ε turbulence model is applied. Various wavy surfaces with different wave heights and wavelengths are selected to conduct numerical experiments with a wide range of gas velocities. The results show that the wave structure can enhance condensation rate up to ten percent mainly due to the alteration of local flow structures in the gas phase. The increments of the condensation rate due to the wavy interface can vary with different gas velocities. The investigation shows that a multiplication factor accounts for the wave effects on film

Mapleson's Breathing Systems.

Science.gov (United States)

Kaul, Tej K; Mittal, Geeta

2013-09-01

Mapleson breathing systems are used for delivering oxygen and anaesthetic agents and to eliminate carbon dioxide during anaesthesia. They consist of different components: Fresh gas flow, reservoir bag, breathing tubes, expiratory valve, and patient connection. There are five basic types of Mapleson system: A, B, C, D and E depending upon the different arrangements of these components. Mapleson F was added later. For adults, Mapleson A is the circuit of choice for spontaneous respiration where as Mapleson D and its Bains modifications are best available circuits for controlled ventilation. For neonates and paediatric patients Mapleson E and F (Jackson Rees modification) are the best circuits. In this review article, we will discuss the structure of the circuits and functional analysis of various types of Mapleson systems and their advantages and disadvantages.

A fully integrated standalone portable cavity ringdown breath acetone analyzer

Science.gov (United States)

Sun, Meixiu; Jiang, Chenyu; Gong, Zhiyong; Zhao, Xiaomeng; Chen, Zhuying; Wang, Zhennan; Kang, Meiling; Li, Yingxin; Wang, Chuji

2015-09-01

Breath analysis is a promising new technique for nonintrusive disease diagnosis and metabolic status monitoring. One challenging issue in using a breath biomarker for potential particular disease screening is to find a quantitative relationship between the concentration of the breath biomarker and clinical diagnostic parameters of the specific disease. In order to address this issue, we need a new instrument that is capable of conducting real-time, online breath analysis with high data throughput, so that a large scale of clinical test (more subjects) can be achieved in a short period of time. In this work, we report a fully integrated, standalone, portable analyzer based on the cavity ringdown spectroscopy technique for near-real time, online breath acetone measurements. The performance of the portable analyzer in measurements of breath acetone was interrogated and validated by using the certificated gas chromatography-mass spectrometry. The results show that this new analyzer is useful for reliable online (online introduction of a breath sample without pre-treatment) breath acetone analysis with high sensitivity (57 ppb) and high data throughput (one data per second). Subsequently, the validated breath analyzer was employed for acetone measurements in 119 human subjects under various situations. The instrument design, packaging, specifications, and future improvements were also described. From an optical ringdown cavity operated by the lab-set electronics reported previously to this fully integrated standalone new instrument, we have enabled a new scientific tool suited for large scales of breath acetone analysis and created an instrument platform that can even be adopted for study of other breath biomarkers by using different lasers and ringdown mirrors covering corresponding spectral fingerprints.

A fully integrated standalone portable cavity ringdown breath acetone analyzer.

Science.gov (United States)

Sun, Meixiu; Jiang, Chenyu; Gong, Zhiyong; Zhao, Xiaomeng; Chen, Zhuying; Wang, Zhennan; Kang, Meiling; Li, Yingxin; Wang, Chuji

2015-09-01

Breath analysis is a promising new technique for nonintrusive disease diagnosis and metabolic status monitoring. One challenging issue in using a breath biomarker for potential particular disease screening is to find a quantitative relationship between the concentration of the breath biomarker and clinical diagnostic parameters of the specific disease. In order to address this issue, we need a new instrument that is capable of conducting real-time, online breath analysis with high data throughput, so that a large scale of clinical test (more subjects) can be achieved in a short period of time. In this work, we report a fully integrated, standalone, portable analyzer based on the cavity ringdown spectroscopy technique for near-real time, online breath acetone measurements. The performance of the portable analyzer in measurements of breath acetone was interrogated and validated by using the certificated gas chromatography-mass spectrometry. The results show that this new analyzer is useful for reliable online (online introduction of a breath sample without pre-treatment) breath acetone analysis with high sensitivity (57 ppb) and high data throughput (one data per second). Subsequently, the validated breath analyzer was employed for acetone measurements in 119 human subjects under various situations. The instrument design, packaging, specifications, and future improvements were also described. From an optical ringdown cavity operated by the lab-set electronics reported previously to this fully integrated standalone new instrument, we have enabled a new scientific tool suited for large scales of breath acetone analysis and created an instrument platform that can even be adopted for study of other breath biomarkers by using different lasers and ringdown mirrors covering corresponding spectral fingerprints.

Assessment of horizontal in-tube condensation models using MARS code. Part I: Stratified flow condensation

Energy Technology Data Exchange (ETDEWEB)

Jeon, Seong-Su [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Hong, Soon-Joon, E-mail: sjhong90@fnctech.com [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Park, Ju-Yeop; Seul, Kwang-Won [Korea Institute of Nuclear Safety, 19 Kuseong-dong, Yuseong-gu, Daejon (Korea, Republic of); Park, Goon-Cherl [Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of)

2013-01-15

Highlights: Black-Right-Pointing-Pointer This study collected 11 horizontal in-tube condensation models for stratified flow. Black-Right-Pointing-Pointer This study assessed the predictive capability of the models for steam condensation. Black-Right-Pointing-Pointer Purdue-PCCS experiments were simulated using MARS code incorporated with models. Black-Right-Pointing-Pointer Cavallini et al. (2006) model predicts well the data for stratified flow condition. Black-Right-Pointing-Pointer Results of this study can be used to improve condensation model in RELAP5 or MARS. - Abstract: The accurate prediction of the horizontal in-tube condensation heat transfer is a primary concern in the optimum design and safety analysis of horizontal heat exchangers of passive safety systems such as the passive containment cooling system (PCCS), the emergency condenser system (ECS) and the passive auxiliary feed-water system (PAFS). It is essential to analyze and assess the predictive capability of the previous horizontal in-tube condensation models for each flow regime using various experimental data. This study assessed totally 11 condensation models for the stratified flow, one of the main flow regime encountered in the horizontal condenser, with the heat transfer data from the Purdue-PCCS experiment using the multi-dimensional analysis of reactor safety (MARS) code. From the assessments, it was found that the models by Akers and Rosson, Chato, Tandon et al., Sweeney and Chato, and Cavallini et al. (2002) under-predicted the data in the main condensation heat transfer region, on the contrary to this, the models by Rosson and Meyers, Jaster and Kosky, Fujii, Dobson and Chato, and Thome et al. similarly- or over-predicted the data, and especially, Cavallini et al. (2006) model shows good predictive capability for all test conditions. The results of this study can be used importantly to improve the condensation models in thermal hydraulic code, such as RELAP5 or MARS code.

Breath-Holding Spells

Science.gov (United States)

... reviewed: October 2016 More on this topic for: Parents Is It Normal for Children to Hold Their Breath? Taming Tempers Disciplining Your Child Disciplining Your Toddler Temper Tantrums Separation Anxiety View more About Us Contact Us Partners ...

Off gas condenser performance modelling

International Nuclear Information System (INIS)

Cains, P.W.; Hills, K.M.; Waring, S.; Pratchett, A.G.

1989-12-01

A suite of three programmes has been developed to model the ruthenium decontamination performance of a vitrification plant off-gas condenser. The stages of the model are: condensation of water vapour, NO x absorption in the condensate, RuO 4 absorption in the condensate. Juxtaposition of these stages gives a package that may be run on an IBM-compatible desktop PC. Experimental work indicates that the criterion [HNO 2 ] > 10 [RuO 4 ] used to determine RuO 4 destruction in solution is probably realistic under condenser conditions. Vapour pressures of RuO 4 over aqueous solutions at 70 o -90 o C are slightly lower than the values given by extrapolating the ln K p vs. T -1 relation derived from lower temperature data. (author)

Progress of air-breathing cathode in microbial fuel cells

Science.gov (United States)

Wang, Zejie; Mahadevan, Gurumurthy Dummi; Wu, Yicheng; Zhao, Feng

2017-07-01

Microbial fuel cell (MFC) is an emerging technology to produce green energy and vanquish the effects of environmental contaminants. Cathodic reactions are vital for high electrical power density generated from MFCs. Recently tremendous attentions were paid towards developing high performance air-breathing cathodes. A typical air-breathing cathode comprises of electrode substrate, catalyst layer, and air-diffusion layer. Prior researches demonstrated that each component influenced the performance of air-breathing cathode MFCs. This review summarized the progress in development of the individual component and elaborated main factors to the performance of air-breathing cathode.

The effects of passive humidifier dead space on respiratory variables in paralyzed and spontaneously breathing patients.

Science.gov (United States)

Campbell, R S; Davis, K; Johannigman, J A; Branson, R D

2000-03-01

Passive humidifiers have gained acceptance in the intensive care unit because of their low cost, simple operation, and elimination of condensate from the breathing circuit. However, the additional dead space of these devices may adversely affect respiratory function in certain patients. This study evaluates the effects of passive humidifier dead space on respiratory function. Two groups of patients were studied. The first group consisted of patients recovering from acute lung injury and breathing spontaneously on pressure support ventilation. The second group consisted of patients who were receiving controlled mechanical ventilation and were chemically paralyzed following operative procedures. All patients used 3 humidification devices in random order for one hour each. The devices were a heated humidifier (HH), a hygroscopic heat and moisture exchanger (HHME) with a dead space of 28 mL, and a heat and moisture exchanger (HME) with a dead space of 90 mL. During each measurement period the following were recorded: tidal volume, minute volume, respiratory frequency, oxygen consumption, carbon dioxide production, ratio of dead space volume to tidal volume (VD/VT), and blood gases. In the second group, intrinsic positive end-expiratory pressure was also measured. Addition of either of the passive humidifiers was associated with increased VD/VT. In spontaneously breathing patients, VD/VT increased from 59 +/- 13 (HH) to 62 +/- 13 (HHME) to 68 +/- 11% (HME) (p < 0.05). In these patients, constant alveolar ventilation was maintained as a result of increased respiratory frequency, from 22.1 +/- 6.6 breaths/min (HH) to 24.5 +/- 6.9 breaths/min (HHME) to 27.7 +/- 7.4 breaths/min (HME) (p < 0.05), and increased minute volume, from 9.1 +/- 3.5 L/min (HH) to 9.9 +/- 3.6 L/min (HHME) to 11.7 +/- 4.2 L/min (HME) (p < 0.05). There were no changes in blood gases or carbon dioxide production. In the paralyzed patient group, VD/VT increased from 54 +/- 12% (HH) to 56 +/- 10% (HHME

Sleep-disordered breathing and mortality: a prospective cohort study.

Directory of Open Access Journals (Sweden)

Naresh M Punjabi

2009-08-01

Full Text Available Sleep-disordered breathing is a common condition associated with adverse health outcomes including hypertension and cardiovascular disease. The overall objective of this study was to determine whether sleep-disordered breathing and its sequelae of intermittent hypoxemia and recurrent arousals are associated with mortality in a community sample of adults aged 40 years or older.We prospectively examined whether sleep-disordered breathing was associated with an increased risk of death from any cause in 6,441 men and women participating in the Sleep Heart Health Study. Sleep-disordered breathing was assessed with the apnea-hypopnea index (AHI based on an in-home polysomnogram. Survival analysis and proportional hazards regression models were used to calculate hazard ratios for mortality after adjusting for age, sex, race, smoking status, body mass index, and prevalent medical conditions. The average follow-up period for the cohort was 8.2 y during which 1,047 participants (587 men and 460 women died. Compared to those without sleep-disordered breathing (AHI: or=30.0 events/h sleep-disordered breathing were 0.93 (95% CI: 0.80-1.08, 1.17 (95% CI: 0.97-1.42, and 1.46 (95% CI: 1.14-1.86, respectively. Stratified analyses by sex and age showed that the increased risk of death associated with severe sleep-disordered breathing was statistically significant in men aged 40-70 y (hazard ratio: 2.09; 95% CI: 1.31-3.33. Measures of sleep-related intermittent hypoxemia, but not sleep fragmentation, were independently associated with all-cause mortality. Coronary artery disease-related mortality associated with sleep-disordered breathing showed a pattern of association similar to all-cause mortality.Sleep-disordered breathing is associated with all-cause mortality and specifically that due to coronary artery disease, particularly in men aged 40-70 y with severe sleep-disordered breathing. Please see later in the article for the Editors' Summary.

Increased Prevalence of Sleep-Disordered Breathing in Adults

Science.gov (United States)

Peppard, Paul E.; Young, Terry; Barnet, Jodi H.; Palta, Mari; Hagen, Erika W.; Hla, Khin Mae

2013-01-01

Sleep-disordered breathing is a common disorder with a range of harmful sequelae. Obesity is a strong causal factor for sleep-disordered breathing, and because of the ongoing obesity epidemic, previous estimates of sleep-disordered breathing prevalence require updating. We estimated the prevalence of sleep-disordered breathing in the United States for the periods of 1988–1994 and 2007–2010 using data from the Wisconsin Sleep Cohort Study, an ongoing community-based study that was established in 1988 with participants randomly selected from an employed population of Wisconsin adults. A total of 1,520 participants who were 30–70 years of age had baseline polysomnography studies to assess the presence of sleep-disordered breathing. Participants were invited for repeat studies at 4-year intervals. The prevalence of sleep-disordered breathing was modeled as a function of age, sex, and body mass index, and estimates were extrapolated to US body mass index distributions estimated using data from the National Health and Nutrition Examination Survey. The current prevalence estimates of moderate to severe sleep-disordered breathing (apnea-hypopnea index, measured as events/hour, ≥15) are 10% (95% confidence interval (CI): 7, 12) among 30–49-year-old men; 17% (95% CI: 15, 21) among 50–70-year-old men; 3% (95% CI: 2, 4) among 30–49-year-old women; and 9% (95% CI: 7, 11) among 50–70 year-old women. These estimated prevalence rates represent substantial increases over the last 2 decades (relative increases of between 14% and 55% depending on the subgroup). PMID:23589584

Dysfunctional breathing: a review of the literature and proposal for classification

Directory of Open Access Journals (Sweden)

Richard Boulding

2016-09-01

Full Text Available Dysfunctional breathing is a term describing breathing disorders where chronic changes in breathing pattern result in dyspnoea and other symptoms in the absence or in excess of the magnitude of physiological respiratory or cardiac disease. We reviewed the literature and propose a classification system for the common dysfunctional breathing patterns described. The literature was searched using the terms: dysfunctional breathing, hyperventilation, Nijmegen questionnaire and thoraco-abdominal asynchrony. We have summarised the presentation, assessment and treatment of dysfunctional breathing, and propose that the following system be used for classification. 1 Hyperventilation syndrome: associated with symptoms both related to respiratory alkalosis and independent of hypocapnia. 2 Periodic deep sighing: frequent sighing with an irregular breathing pattern. 3 Thoracic dominant breathing: can often manifest in somatic disease, if occurring without disease it may be considered dysfunctional and results in dyspnoea. 4 Forced abdominal expiration: these patients utilise inappropriate and excessive abdominal muscle contraction to aid expiration. 5 Thoraco-abdominal asynchrony: where there is delay between rib cage and abdominal contraction resulting in ineffective breathing mechanics. This review highlights the common abnormalities, current diagnostic methods and therapeutic implications in dysfunctional breathing. Future work should aim to further investigate the prevalence, clinical associations and treatment of these presentations.

Can audio coached 4D CT emulate free breathing during the treatment course?

International Nuclear Information System (INIS)

Persson, Gitte F.; Nygaard, Ditte E.; Olsen, Mikael; Juhler-Noettrup, Trine; Pedersen, Anders N.; Specht, Lena; Korreman, Stine S.

2008-01-01

Background. The image quality of 4DCT depends on breathing regularity. Respiratory audio coaching may improve regularity and reduce motion artefacts. We question the safety of coached planning 4DCT without coaching during treatment. We investigated the possibility of coaching to a more stable breathing without changing the breathing amplitude. The interfraction variation of the breathing cycle amplitude in free and coached breathing was studied as well as the possible impact of fatigue on longer coaching sessions. Methods. Thirteen volunteers completed respiratory audio coaching on 3 days within a 2 week period. An external marker system monitoring the motion of the thoraco-abdominal wall was used to track the respiration. On all days, free breathing and two coached breathing curves were recorded. We assumed that free versus coached breathing from day 1 (reference session) simulated breathing during an uncoached versus coached planning 4DCT, respectively, and compared the mean breathing cycle amplitude to the free versus coached breathing from day 2 and 3 simulating free versus coached breathing during treatment. Results. For most volunteers it was impossible to apply coaching without changes in breathing cycle amplitude. No significant decrease in standard deviation of breathing cycle amplitude distribution was seen. Generally it was not possible to predict the breathing cycle amplitude and its variation the following days based on the breathing in the reference session irrespective of coaching or free breathing. We found a significant tendency towards an increased breathing cycle amplitude variation with the duration of the coaching session. Conclusion. These results suggest that large interfraction variation is present in breathing amplitude irrespective of coaching, leading to the suggestion of daily image guidance for verification of respiratory pattern and tumour related motion. Until further investigated it is not recommendable to use coached 4DCT for

Can audio coached 4D CT emulate free breathing during the treatment course?

Energy Technology Data Exchange (ETDEWEB)

Persson, Gitte F.; Nygaard, Ditte E.; Olsen, Mikael; Juhler-Noettrup, Trine; Pedersen, Anders N.; Specht, Lena; Korreman, Stine S. (Dept. of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark))

2008-08-15

Background. The image quality of 4DCT depends on breathing regularity. Respiratory audio coaching may improve regularity and reduce motion artefacts. We question the safety of coached planning 4DCT without coaching during treatment. We investigated the possibility of coaching to a more stable breathing without changing the breathing amplitude. The interfraction variation of the breathing cycle amplitude in free and coached breathing was studied as well as the possible impact of fatigue on longer coaching sessions. Methods. Thirteen volunteers completed respiratory audio coaching on 3 days within a 2 week period. An external marker system monitoring the motion of the thoraco-abdominal wall was used to track the respiration. On all days, free breathing and two coached breathing curves were recorded. We assumed that free versus coached breathing from day 1 (reference session) simulated breathing during an uncoached versus coached planning 4DCT, respectively, and compared the mean breathing cycle amplitude to the free versus coached breathing from day 2 and 3 simulating free versus coached breathing during treatment. Results. For most volunteers it was impossible to apply coaching without changes in breathing cycle amplitude. No significant decrease in standard deviation of breathing cycle amplitude distribution was seen. Generally it was not possible to predict the breathing cycle amplitude and its variation the following days based on the breathing in the reference session irrespective of coaching or free breathing. We found a significant tendency towards an increased breathing cycle amplitude variation with the duration of the coaching session. Conclusion. These results suggest that large interfraction variation is present in breathing amplitude irrespective of coaching, leading to the suggestion of daily image guidance for verification of respiratory pattern and tumour related motion. Until further investigated it is not recommendable to use coached 4DCT for

Condensate from a two-stage gasifier

DEFF Research Database (Denmark)

Bentzen, Jens Dall; Henriksen, Ulrik Birk; Hindsgaul, Claus

2000-01-01

Condensate, produced when gas from downdraft biomass gasifier is cooled, contains organic compounds that inhibit nitrifiers. Treatment with activated carbon removes most of the organics and makes the condensate far less inhibitory. The condensate from an optimised two-stage gasifier is so clean...... that the organic compounds and the inhibition effect are very low even before treatment with activated carbon. The moderate inhibition effect relates to a high content of ammonia in the condensate. The nitrifiers become tolerant to the condensate after a few weeks of exposure. The level of organic compounds...... and the level of inhibition are so low that condensate from the optimised two-stage gasifier can be led to the public sewer....

SU-E-J-62: Breath Hold for Left-Sided Breast Cancer: Visually Monitored Deep Inspiration Breath Hold Amplitude Evaluated Using Real-Time Position Management

Energy Technology Data Exchange (ETDEWEB)

Conroy, L; Quirk, S; Smith, WL [The University of Calgary, Calgary, AB (Canada); Tom Baker Cancer Centre, Calgary, AB (Canada); Yeung, R; Phan, T [The University of Calgary, Calgary, AB (Canada); Hudson, A [Tom Baker Cancer Centre, Calgary, AB (Canada)

2015-06-15

Purpose: We used Real-Time Position Management (RPM) to evaluate breath hold amplitude and variability when gating with a visually monitored deep inspiration breath hold technique (VM-DIBH) with retrospective cine image chest wall position verification. Methods: Ten patients with left-sided breast cancer were treated using VM-DIBH. Respiratory motion was passively collected once weekly using RPM with the marker block positioned at the xiphoid process. Cine images on the tangent medial field were acquired on fractions with RPM monitoring for retrospective verification of chest wall position during breath hold. The amplitude and duration of all breath holds on which treatment beams were delivered were extracted from the RPM traces. Breath hold position coverage was evaluated for symmetric RPM gating windows from ± 1 to 5 mm centered on the average breath hold amplitude of the first measured fraction as a baseline. Results: The average (range) breath hold amplitude and duration was 18 mm (3–36 mm) and 19 s (7–34 s). The average (range) of amplitude standard deviation per patient over all breath holds was 2.7 mm (1.2–5.7 mm). With the largest allowable RPM gating window (± 5 mm), 4 of 10 VM-DIBH patients would have had ≥ 10% of their breath hold positions excluded by RPM. Cine verification of the chest wall position during the medial tangent field showed that the chest wall was greater than 5 mm from the baseline in only 1 out of 4 excluded patients. Cine images verify the chest wall/breast position only, whether this variation is acceptable in terms of heart sparing is a subject of future investigation. Conclusion: VM-DIBH allows for greater breath hold amplitude variability than using a 5 mm gating window with RPM, while maintaining chest wall positioning accuracy within 5 mm for the majority of patients.

Assessment of RELAP5/MOD3.3 condensation models for the tube bundle condensation in the PCCS of ESBWR

International Nuclear Information System (INIS)

Zhou, W.; Wolf, B.; Revankar, S.T.

2011-01-01

The passive containment condenser system (PCCS) in an ESBWR reactor consists of vertical tube bundle submerged in a large pool of water. The condensation model for the PCCS in a thermalhydraulics code RELAP5/MOD3.3 consists of the default Nusselt model and an alternate condensation model from UCB condensation correlation. An assessment of the PCCS condensation model in RELAP5/MOD3.3 was carried out using experiments conducted on a single tube and tube bundle PCCS tests at Purdue University. The experimental conditions were simulated with the default and the alternate condensation models in the REALP5/MOD3.3 beta version of the code. The default model and the UCB model (alternate model) give quite different results on condensation heat transfer for the PCCS. The default model predicts complete condensation well whereas the UCB model predicts the through flow condensation well. Based on this study it was found that none of the models in REALP5 can predict complete condensation as well as the through flow condensation well. (author)

Assessment of RELAP5/MOD3.3 condensation models for the tube bundle condensation in the PCCS of ESBWR

Energy Technology Data Exchange (ETDEWEB)

Zhou, W., E-mail: wenzzhou@cityu.edu.hk [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong (China); Wolf, B. [Purdue University, West Lafayette, IN 47907 (United States); Revankar, S. [Purdue University, West Lafayette, IN 47907 (United States); POSTECH, Pohang (Korea, Republic of)

2013-11-15

The passive containment condenser system (PCCS) in an ESBWR reactor consists of vertical tube bundle submerged in a large pool of water. The condensation model for the PCCS in a thermalhydraulics code RELAP5/MOD3.3 consists of the default Nusselt model and an alternate condensation model from UCB condensation correlation. An assessment of the PCCS condensation model in RELAP5/MOD3.3 was carried out using experiments conducted on a single tube and tube bundle PCCS tests at Purdue University. The experimental conditions were simulated with the default and the alternate condensation models in the REALP5/MOD3.3 beta version of the code. The default model and the UCB model (alternate model) give quite different results on condensation heat transfer for the PCCS. The default model predicts complete condensation well whereas the UCB model predicts the through flow condensation well. Based on this study it was found that none of the models in REALP5 can predict complete condensation as well as the through flow condensation well.

21 CFR 868.2375 - Breathing frequency monitor.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing frequency monitor. 868.2375 Section 868.2375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2375 Breathing frequency monitor. (a...

Tuning the pore composition by two simultaneous interfacial self-assembly processes: breath figures and coffee stain.

Science.gov (United States)

de León, Alberto S; del Campo, Adolfo; Fernández-García, Marta; Rodríguez-Hernández, Juan; Muñoz-Bonilla, Alexandra

2014-06-03

In the current paper, we prepared microstructured porous films by the breath figures approach using polymer blends consisting of polystyrene as the major component and an amphiphilic additive, either a synthetic block copolymer {two different polystyrene-b-poly[poly(ethylene glycol) methyl ether methacrylate] copolymers} or a series of commercial surfactants. Tetrahydrofuran was employed as the solvent. Confocal micro-Raman spectroscopy demonstrated the preferential location of the amphiphilic additives in the cavities of the film as a consequence of the breath figures mechanism. However, the distribution of the copolymer within the cavities varies depending upon the structure and, more precisely, the surface properties of the additives, leading to three different situations. First of all, the copolymer with a larger polystyrene segment, insoluble in the condensed water droplets, is homogeneously distributed along the whole surface of the cavities. On the contrary, when the copolymer is soluble in water (shorter polystyrene segment), it migrates inside the droplet and a coffee-stain phenomenon takes place during the water droplet evaporation, conducting to a ring-like deposition on the top edge of the cavities. Finally, when a water-soluble surfactant with high surface activity is used, the surfactant is solubilized inside the water droplets, which provokes a decrease on the surface tension and the coffee-ring effect is modified. In this situation, the copolymer covers the bottom of the pore.

Effects of high-frequency yoga breathing called kapalabhati compared with breath awareness on the degree of optical illusion perceived.

Science.gov (United States)

Telles, Shirley; Maharana, Kanchan; Balrana, Budhi; Balkrishna, Acharya

2011-06-01

Prior research has shown that methods of meditation, breath control, and different kinds of yoga breathing affect attention and visual perception, including decreasing the size of certain optical illusions. Evaluating relationships sheds light on the perceptual and cognitive changes induced by yoga and related methods, and the locus of the effects. In the present study, the degree of optical illusion was assessed using Müller-Lyer stimuli before and immediately after two different kinds of practice, a high frequency yoga breathing called kapalabhati, and breath awareness. A nonyoga, control session tested for practice effects. Thirty participants (with group M age = 26.9 yr., SD = 5.7) practiced the two techniques for 18 min. on two separate days. The control group had 15 nonyoga practitioners assessed before and after 18 min. in which they did not perform any specific activity but were seated and relaxed. After both kapalabhati and breath awareness there was a significant decrease in the degree of optical illusion. The possibility that this was due to a practice or repetition effect was ruled out when 15 nonyoga practitioners showed no change in the degree of illusion when retested after 18 min. The changes were interpreted as due to changes in perception related to the way the stimuli were judged.

Usefulness of Guided Breathing for Dose Rate-Regulated Tracking

International Nuclear Information System (INIS)

Han-Oh, Sarah; Yi, Byong Yong; Berman, Barry L.; Lerma, Fritz; Yu, Cedric

2009-01-01

Purpose: To evaluate the usefulness of guided breathing for dose rate-regulated tracking (DRRT), a new technique to compensate for intrafraction tumor motion. Methods and Materials: DRRT uses a preprogrammed multileaf collimator sequence that tracks the tumor motion derived from four-dimensional computed tomography and the corresponding breathing signals measured before treatment. Because the multileaf collimator speed can be controlled by adjusting the dose rate, the multileaf collimator positions are adjusted in real time during treatment by dose rate regulation, thereby maintaining synchrony with the tumor motion. DRRT treatment was simulated with free, audio-guided, and audiovisual-guided breathing signals acquired from 23 lung cancer patients. The tracking error and duty cycle for each patient were determined as a function of the system time delay (range, 0-1.0 s). Results: The tracking error and duty cycle averaged for all 23 patients was 1.9 ± 0.8 mm and 92% ± 5%, 1.9 ± 1.0 mm and 93% ± 6%, and 1.8 ± 0.7 mm and 92% ± 6% for the free, audio-guided, and audiovisual-guided breathing, respectively, for a time delay of 0.35 s. The small differences in both the tracking error and the duty cycle with guided breathing were not statistically significant. Conclusion: DRRT by its nature adapts well to variations in breathing frequency, which is also the motivation for guided-breathing techniques. Because of this redundancy, guided breathing does not result in significant improvements for either the tracking error or the duty cycle when DRRT is used for real-time tumor tracking

The Effect of Capillary Number on a Condensate Blockage in Gas Condensate Reservoirs

OpenAIRE

Saifon DAUNGKAEW; Alain C GRINGARTEN

2004-01-01

In the petroleum industry, gas condensate reservoirs are becoming more common as exploration targets. However, there is a lack of knowledge of the reservoir behaviour mainly due to its complexity in the near wellbore region, where two phases, i.e. reservoir gas and condensate coexist when the wellbore pressure drops below the dew point pressure. The condensation process causes a reduction of the gas productivity (1). It has been reported in the literature that there is an increasing gas mobil...

Ghost condensate and generalized second law

International Nuclear Information System (INIS)

Mukohyama, Shinji

2009-01-01

Dubovsky and Sibiryakov recently proposed a scenario in which particles of different species propagate with different speeds due to their direct couplings to ghost condensate. It was argued that this extended version of ghost condensate allows a gedanken experiment leading to violation of the generalized second law. However, in the original ghost condensate scenario, difference in propagation speeds is suppressed by M 2 /M Pl 2 , where M is the order parameter of spontaneous Lorentz breaking and M Pl is the Planck scale. In this case the energy transfer necessary for the gedanken experiment is so slow that the timescale of decrease of entropy, if any, is always longer than the Jeans timescale of ghost condensate. Hence the generalized second law is not violated by the gedanken experiment in the original ghost condensate scenario. This conclusion trivially extends to gauged ghost condensation by taking into account accretion of gauged ghost condensate into a black hole.

Black holes in the ghost condensate

International Nuclear Information System (INIS)

Mukohyama, Shinji

2005-01-01

We investigate how the ghost condensate reacts to black holes immersed in it. A ghost condensate defines a hypersurface-orthogonal congruence of timelike curves, each of which has the tangent vector u μ =-g μν ∂ ν φ. It is argued that the ghost condensate in this picture approximately corresponds to a congruence of geodesics. In other words, the ghost condensate accretes into a black hole just like a pressureless dust. Correspondingly, if the energy density of the ghost condensate at large distance is set to an extremely small value by cosmic expansion then the late-time accretion rate of the ghost condensate should be negligible. The accretion rate remains very small even if effects of higher derivative terms are taken into account, provided that the black hole is sufficiently large. It is also discussed how to reconcile the black-hole accretion with the possibility that the ghost condensate might behave like dark matter

Sleep-disordered breathing in epilepsy: epidemiology, mechanisms, and treatment.

Science.gov (United States)

Sivathamboo, Shobi; Perucca, Piero; Velakoulis, Dennis; Jones, Nigel C; Goldin, Jeremy; Kwan, Patrick; O'Brien, Terence J

2018-04-01

Epilepsy is a group of neurological conditions in which there is a pathological and enduring predisposition to generate recurrent seizures. Evidence over the last few decades suggests that epilepsy may be associated with increased sleep-disordered breathing, which may contribute towards sleep fragmentation, daytime somnolence, reduced seizure control, and cardiovascular-related morbidity and mortality. Chronic sleep-disordered breathing can result in loss of gray matter and cause deficits to memory and global cognitive function. Sleep-disordered breathing is a novel and independent predictor of sudden cardiac death and, as such, may be involved in the mechanisms leading to sudden unexpected death in epilepsy. Despite this, the long-term consequences of sleep-disordered breathing in epilepsy remain unknown, and there are no guidelines for screening or treating this population. There is currently insufficient evidence to indicate continuous positive airway pressure (CPAP) for the primary or secondary prevention of cardiovascular disease, and recent evidence has failed to show any reduction of fatal or nonfatal cardiovascular endpoints. Treatment of sleep-disordered breathing may potentially improve seizure control, daytime somnolence, and neurocognitive outcomes, but few studies have examined this relationship. In this review, we examine sleep-disordered breathing in epilepsy, and discuss the potential effect of epilepsy treatments. We consider the role of CPAP and other interventions for sleep-disordered breathing and discuss their implications for epilepsy management.

Physics of condensed matter

CERN Document Server

Misra, Prasanta K

2012-01-01

Physics of Condensed Matter is designed for a two-semester graduate course on condensed matter physics for students in physics and materials science. While the book offers fundamental ideas and topic areas of condensed matter physics, it also includes many recent topics of interest on which graduate students may choose to do further research. The text can also be used as a one-semester course for advanced undergraduate majors in physics, materials science, solid state chemistry, and electrical engineering, because it offers a breadth of topics applicable to these majors. The book be

Pion condensation and neutron star dynamics

International Nuclear Information System (INIS)

Kaempfer, B.

1983-01-01

The question of formation of pion condensate via a phase transition in nuclear matter, especially in the core of neutron stars is reviewed. The possible mechanisms and the theoretical restrictions of pion condensation are summarized. The effects of ultradense equation of state and density jumps on the possible condensation phase transition are investigated. The possibilities of observation of condensation process are described. (D.Gy.)

Voluntary Breath-hold Technique for Reducing Heart Dose in Left Breast Radiotherapy

Science.gov (United States)

Bartlett, Frederick R.; Colgan, Ruth M.; Donovan, Ellen M.; Carr, Karen; Landeg, Steven; Clements, Nicola; McNair, Helen A.; Locke, Imogen; Evans, Philip M.; Haviland, Joanne S.; Yarnold, John R.; Kirby, Anna M.

2014-01-01

Breath-holding techniques reduce the amount of radiation received by cardiac structures during tangential-field left breast radiotherapy. With these techniques, patients hold their breath while radiotherapy is delivered, pushing the heart down and away from the radiotherapy field. Despite clear dosimetric benefits, these techniques are not yet in widespread use. One reason for this is that commercially available solutions require specialist equipment, necessitating not only significant capital investment, but often also incurring ongoing costs such as a need for daily disposable mouthpieces. The voluntary breath-hold technique described here does not require any additional specialist equipment. All breath-holding techniques require a surrogate to monitor breath-hold consistency and whether breath-hold is maintained. Voluntary breath-hold uses the distance moved by the anterior and lateral reference marks (tattoos) away from the treatment room lasers in breath-hold to monitor consistency at CT-planning and treatment setup. Light fields are then used to monitor breath-hold consistency prior to and during radiotherapy delivery. PMID:25046661

MATHEMATICAL MODELING AND NUMERICAL SOLUTION OF IRON CORROSION PROBLEM BASED ON CONDENSATION CHEMICAL PROPERTIES

Directory of Open Access Journals (Sweden)

Basuki Widodo

2012-02-01

Full Text Available Corrosion process is a natural case that happened at the various metals, where the corrosion process in electrochemical can be explained by using galvanic cell. The iron corrosion process is based on the acidity degree (pH of a condensation, iron concentration and condensation temperature of electrolyte. Those are applied at electrochemistry cell. The iron corrosion process at this electrochemical cell also able to generate electrical potential and electric current during the process takes place. This paper considers how to build a mathematical model of iron corrosion, electrical potential and electric current. The mathematical model further is solved using the finite element method. This iron corrosion model is built based on the iron concentration, condensation temperature, and iteration time applied. In the electric current density model, the current based on electric current that is happened at cathode and anode pole and the iteration time applied. Whereas on the potential  electric model, it is based on the beginning of electric potential and the iteration time applied. The numerical results show that the part of iron metal, that is gristle caused by corrosion, is the part of metal that has function as anode and it has some influences, such as time depth difference, iron concentration and condensation temperature on the iron corrosion process and the sum of reduced mass during corrosion process. Moreover, difference influence of time and beginning electric potential has an effect on the electric potential, which emerges during corrosion process at the electrochemical cell. Whereas, at the electrical current is also influenced by difference of depth time and condensation temperature applied.Keywords: Iron Corrosion, Concentration of iron, Electrochemical Cell and Finite Element Method

The Effect of mechanical resistive loading on optimal respiratory signals and breathing patterns under added dead space and CO2 breathing

Directory of Open Access Journals (Sweden)

Lin Shyan-Lung

2016-01-01

Full Text Available Current study aims to investigate how the respiratory resistive loading affects the behaviour of the optimal chemical-mechanical respiratory control model, the respiratory signals and breathing pattern are optimized under external dead space loading and CO2 breathing. The respiratory control was modelled to include a neuro-muscular drive as the control output to derive the waveshapes of instantaneous airflow, lung volume profiles, and breathing pattern, including total/alveolar ventilation, breathing frequency, tidal volume, inspiratory/expiratory duration, duty cycle, and arterial CO2 pressure. The simulations were performed under various respiratory resistive loads, including no load, inspiratory resistive load, expiratory resistive load, and continuous resistive load. The dead space measurement was described with Gray’s derivation, and simulation results were studied and compared with experimental findings.

Optimal design of condenser weight

International Nuclear Information System (INIS)

Zheng Jing; Yan Changqi; Wang Jianjun

2011-01-01

The condenser is an important component in nuclear power plants, which dimension and weight will effect the economical performance and the arrangement of the nuclear power plants. In this paper, the calculation model is established according to the design experience. The corresponding codes are also developed, and the sensitivity of design parameters which influence the condenser weight is analyzed. The present design optimization of the condenser, taking the weight minimization as the objective, is carried out with the self-developed complex-genetic algorithm. The results show that the reference condenser design is far from the best scheme, and also verify the feasibility of the complex-genetic algorithm. (authors)

Breath acetone monitoring by portable Si:WO3 gas sensors

International Nuclear Information System (INIS)

Righettoni, Marco; Tricoli, Antonio; Gass, Samuel; Schmid, Alex; Amann, Anton; Pratsinis, Sotiris E.

2012-01-01

Highlights: ► Portable sensors were developed and tested for monitoring acetone in the human breath. ► Acetone concentrations down to 20 ppb were measured with short response times ( 3 nanostructured films was developed. The chamber volume was miniaturized while reaction-limited and transport-limited gas flow rates were identified and sensing temperatures were optimized resulting in a low detection limit of acetone (∼20 ppb) with short response (10–15 s) and recovery times (35–70 s). Furthermore, the sensor signal (response) was robust against variations of the exhaled breath flow rate facilitating application of these sensors at realistic relative humidities (80–90%) as in the human breath. The acetone content in the breath of test persons was monitored continuously and compared to that of state-of-the-art proton transfer reaction mass spectrometry (PTR-MS). Such portable devices can accurately track breath acetone concentration to become an alternative to more elaborate breath analysis techniques.

The physics of exciton-polariton condensates

CERN Document Server

Lagoudakis, Konstantinos

2013-01-01

In 2006 researchers created the first polariton Bose-Einstein condensate at 19K in the solid state. Being inherently open quantum systems, polariton condensates open a window into the unpredictable world of physics beyond the “fifth state of matter”: the limited lifetime of polaritons renders polariton condensates out-of-equilibrium and provides a fertile test-bed for non-equilibrium physics. This book presents an experimental investigation into exciting features arising from this non-equilibrium behavior. Through careful experimentation, the author demonstrates the ability of polaritons to synchronize and create a single energy delocalized condensate. Under certain disorder and excitation conditions the complete opposite case of coexisting spatially overlapping condensates may be observed. The author provides the first demonstration of quantized vortices in polariton condensates and the first observation of fractional vortices with full phase and amplitude characterization. Finally, this book investigate...

Remote monitoring of breathing dynamics using infrared thermography.

Science.gov (United States)

Pereira, Carina Barbosa; Yu, Xinchi; Czaplik, Michael; Rossaint, Rolf; Blazek, Vladimir; Leonhardt, Steffen

2015-11-01

An atypical or irregular respiratory frequency is considered to be one of the earliest markers of physiological distress. In addition, monitoring of this vital parameter plays a major role in diagnosis of respiratory disorders, as well as in early detection of sudden infant death syndrome. Nevertheless, the current measurement modalities require attachment of sensors to the patient's body, leading to discomfort and stress. The current paper presents a new robust algorithm to remotely monitor breathing rate (BR) by using thermal imaging. This approach permits to detect and to track the region of interest (nose) as well as to estimate BR. In order to study the performance of the algorithm, and its robustness against motion and breathing disorders, three different thermal recordings of 11 healthy volunteers were acquired (sequence 1: normal breathing; sequence 2: normal breathing plus arbitrary head movements; and sequence 3: sequence of specific breathing patterns). Thoracic effort (piezoplethysmography) served as "gold standard" for validation of our results. An excellent agreement between estimated BR and ground truth was achieved. Whereas the mean correlation for sequence 1-3 were 0.968, 0.940 and 0.974, the mean absolute BR errors reached 0.33, 0.55 and 0.96 bpm (breaths per minute), respectively. In brief, this work demonstrates that infrared thermography is a promising, clinically relevant alternative for the currently available measuring modalities due to its performance and diverse remarkable advantages.

A simple, remote, video based breathing monitor.

Science.gov (United States)

Regev, Nir; Wulich, Dov

2017-07-01

Breathing monitors have become the all-important cornerstone of a wide variety of commercial and personal safety applications, ranging from elderly care to baby monitoring. Many such monitors exist in the market, some, with vital signs monitoring capabilities, but none remote. This paper presents a simple, yet efficient, real time method of extracting the subject's breathing sinus rhythm. Points of interest are detected on the subject's body, and the corresponding optical flow is estimated and tracked using the well known Lucas-Kanade algorithm on a frame by frame basis. A generalized likelihood ratio test is then utilized on each of the many interest points to detect which is moving in harmonic fashion. Finally, a spectral estimation algorithm based on Pisarenko harmonic decomposition tracks the harmonic frequency in real time, and a fusion maximum likelihood algorithm optimally estimates the breathing rate using all points considered. The results show a maximal error of 1 BPM between the true breathing rate and the algorithm's calculated rate, based on experiments on two babies and three adults.

Sex differences in sleep disordered breathing in adults.

Science.gov (United States)

Lozo, Tijana; Komnenov, Dragana; Badr, M Safwan; Mateika, Jason H

2017-11-01

The prevalence of sleep disordered breathing is greater in men compared to women. This disparity could be due to sex differences in the diagnosis and presentation of sleep apnea, and the pathophysiological mechanisms that instigate this disorder. Women tend to report more non-typical symptoms of sleep apnea compared to men, and the presentation of apneic events are more prevalent in rapid compared to non-rapid eye movement sleep. In addition, there is evidence of sex differences in upper airway structure and mechanics and in neural mechanisms that impact on the control of breathing. The purpose of this review is to summarize the literature that addresses sex differences in sleep-disordered breathing, and to discuss the influence that upper airway mechanics, chemoreflex properties, and sex hormones have in modulating breathing during sleep in men and women. Published by Elsevier B.V.

Awareness of breathing: the structure of language descriptors of respiratory sensations.

Science.gov (United States)

Petersen, Sibylle; Orth, Bernhard; Ritz, Thomas

2008-01-01

Recent research suggests that dyspnea is not a single sensation but a multidimensional construct reflected in different verbal descriptors that can provide useful diagnostic information. In this study superordinated clusters of dyspnea were investigated in combination with a dimensional approach. We examined the use of 20 respiratory symptom descriptors by healthy volunteers who completed a protocol of seven experimental conditions: Quiet breathing, breath holding, paced breathing, climbing stairs, resistive load breathing, voluntary hyperinflation, and voluntary hyperventilation. We analyzed the ratings of these descriptors with multidimensional scaling (MDS) and cluster analysis. While similarities with prior studies were found on a lower fusion level, we were able to demonstrate the usefulness of interpreting higher fusion levels with four clusters related to work of breathing, coordination, suffocation, and struggling for air, merging into two superordinated clusters, effort and air hunger that are compatible with widely accepted primary components of dyspnea. MDS results also suggested that future studies should consider further breathing sensations related to cognitive control of breathing.

Analysis of human exhaled breath in a population of young volunteers

Directory of Open Access Journals (Sweden)

Zarić Božidarka

2014-01-01

Full Text Available Analysis of volatile organic compounds (VOCs in human breath can provide information about the current physiological state of an individual, such as clinical conditions and exposure to exogenous pollutants. The blood-borne VOCs present in exhaled breath offer the possibility of exploring physiological and pathological processes in a noninvasive way. However, the field of exhaled breath analysis is still in its infancy. We undertook this study in order to define interindividual variation and common compounds in breath VOCs of 48 young human volunteers. Alveolar breath samples were analyzed by automated thermal desorption, gas chromatography with flame ionization detector (FID and electron capture detector (ECD using SUPELCO standards with 66 compounds. Predominant compounds in the alveolar breath of analyzed subjects are ethylbenzene, 1-ethyl-4-methylbenzene, 1,2,4-trimethylbenzene and 1,3,5-trimethylbenzene (over 50% of the subjects. Isopropyl alcohol, propylene, acetone, ethanol were found as well. We detected substituted compounds in exhaled breath. [Projekat Ministarstva nauke Republike Srbije, br. 172001

Breathing multichimera states in nonlocally coupled phase oscillators

Science.gov (United States)

Suda, Yusuke; Okuda, Koji

2018-04-01

Chimera states for the one-dimensional array of nonlocally coupled phase oscillators in the continuum limit are assumed to be stationary states in most studies, but a few studies report the existence of breathing chimera states. We focus on multichimera states with two coherent and incoherent regions and numerically demonstrate that breathing multichimera states, whose global order parameter oscillates temporally, can appear. Moreover, we show that the system exhibits a Hopf bifurcation from a stationary multichimera to a breathing one by the linear stability analysis for the stationary multichimera.

Spike-Timing of Orbitofrontal Neurons Is Synchronized With Breathing.

Science.gov (United States)

Kőszeghy, Áron; Lasztóczi, Bálint; Forro, Thomas; Klausberger, Thomas

2018-01-01

The orbitofrontal cortex (OFC) has been implicated in a multiplicity of complex brain functions, including representations of expected outcome properties, post-decision confidence, momentary food-reward values, complex flavors and odors. As breathing rhythm has an influence on odor processing at primary olfactory areas, we tested the hypothesis that it may also influence neuronal activity in the OFC, a prefrontal area involved also in higher order processing of odors. We recorded spike timing of orbitofrontal neurons as well as local field potentials (LFPs) in awake, head-fixed mice, together with the breathing rhythm. We observed that a large majority of orbitofrontal neurons showed robust phase-coupling to breathing during immobility and running. The phase coupling of action potentials to breathing was significantly stronger in orbitofrontal neurons compared to cells in the medial prefrontal cortex. The characteristic synchronization of orbitofrontal neurons with breathing might provide a temporal framework for multi-variable processing of olfactory, gustatory and reward-value relationships.

Spike-Timing of Orbitofrontal Neurons Is Synchronized With Breathing

Directory of Open Access Journals (Sweden)

Áron Kőszeghy

2018-04-01

Full Text Available The orbitofrontal cortex (OFC has been implicated in a multiplicity of complex brain functions, including representations of expected outcome properties, post-decision confidence, momentary food-reward values, complex flavors and odors. As breathing rhythm has an influence on odor processing at primary olfactory areas, we tested the hypothesis that it may also influence neuronal activity in the OFC, a prefrontal area involved also in higher order processing of odors. We recorded spike timing of orbitofrontal neurons as well as local field potentials (LFPs in awake, head-fixed mice, together with the breathing rhythm. We observed that a large majority of orbitofrontal neurons showed robust phase-coupling to breathing during immobility and running. The phase coupling of action potentials to breathing was significantly stronger in orbitofrontal neurons compared to cells in the medial prefrontal cortex. The characteristic synchronization of orbitofrontal neurons with breathing might provide a temporal framework for multi-variable processing of olfactory, gustatory and reward-value relationships.

TASK-2 Channels Contribute to pH Sensitivity of Retrotrapezoid Nucleus Chemoreceptor Neurons

Science.gov (United States)

Wang, Sheng; Benamer, Najate; Zanella, Sébastien; Kumar, Natasha N.; Shi, Yingtang; Bévengut, Michelle; Penton, David; Guyenet, Patrice G.; Lesage, Florian

2013-01-01

Phox2b-expressing glutamatergic neurons of the retrotrapezoid nucleus (RTN) display properties expected of central respiratory chemoreceptors; they are directly activated by CO2/H+ via an unidentified pH-sensitive background K+ channel and, in turn, facilitate brainstem networks that control breathing. Here, we used a knock-out mouse model to examine whether TASK-2 (K2P5), an alkaline-activated background K+ channel, contributes to RTN neuronal pH sensitivity. We made patch-clamp recordings in brainstem slices from RTN neurons that were identified by expression of GFP (directed by the Phox2b promoter) or β-galactosidase (from the gene trap used for TASK-2 knock-out). Whereas nearly all RTN cells from control mice were pH sensitive (95%, n = 58 of 61), only 56% of GFP-expressing RTN neurons from TASK-2−/− mice (n = 49 of 88) could be classified as pH sensitive (>30% reduction in firing rate from pH 7.0 to pH 7.8); the remaining cells were pH insensitive (44%). Moreover, none of the recorded RTN neurons from TASK-2−/− mice selected based on β-galactosidase activity (a subpopulation of GFP-expressing neurons) were pH sensitive. The alkaline-activated background K+ currents were reduced in amplitude in RTN neurons from TASK-2−/− mice that retained some pH sensitivity but were absent from pH-insensitive cells. Finally, using a working heart–brainstem preparation, we found diminished inhibition of phrenic burst amplitude by alkalization in TASK-2−/− mice, with apneic threshold shifted to higher pH levels. In conclusion, alkaline-activated TASK-2 channels contribute to pH sensitivity in RTN neurons, with effects on respiration in situ that are particularly prominent near apneic threshold. PMID:24107938

A single pH fluorescent probe for biosensing and imaging of extreme acidity and extreme alkalinity.

Science.gov (United States)

Chao, Jian-Bin; Wang, Hui-Juan; Zhang, Yong-Bin; Li, Zhi-Qing; Liu, Yu-Hong; Huo, Fang-Jun; Yin, Cai-Xia; Shi, Ya-Wei; Wang, Juan-Juan

2017-07-04

A simple tailor-made pH fluorescent probe 2-benzothiazole (N-ethylcarbazole-3-yl) hydrazone (Probe) is facilely synthesized by the condensation reaction of 2-hydrazinobenzothiazole with N-ethylcarbazole-3-formaldehyde, which is a useful fluorescent probe for monitoring extremely acidic and alkaline pH, quantitatively. The pH titrations indicate that Probe displays a remarkable emission enhancement with a pK a of 2.73 and responds linearly to minor pH fluctuations within the extremely acidic range of 2.21-3.30. Interestingly, Probe also exhibits strong pH-dependent characteristics with pK a 11.28 and linear response to extreme-alkalinity range of 10.41-12.43. In addition, Probe shows a large Stokes shift of 84 nm under extremely acidic and alkaline conditions, high selectivity, excellent sensitivity, good water-solubility and fine stability, all of which are favorable for intracellular pH imaging. The probe is further successfully applied to image extremely acidic and alkaline pH values fluctuations in E. coli cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Transient direct-contact condensation on liquid droplets

International Nuclear Information System (INIS)

Pasamehmetoglu, K.O.; Nelson, R.A.

1987-01-01

In this paper, direct-contact condensation on subcooled liquid droplets is studied in two parts. In the first part, simple design correlations for the condensation in a steady environment are developed based upon a conduction model. These correlations include the convective heat-transfer coefficient, condensation rate, total condensation, and the droplet-thermalization time. In the second part of the paper, the effect of a time-dependent saturation temperature on the condensation process is investigated. A rapid decrease in saturation temperature is typical of condensation environments in which the steam-supply rate is limited and condensation-induced depressurization becomes important. Design correlations are developed for condensation in an environment in which the saturation temperature decreases linearly with time. These correlations are graphically compared to the design correlations of the first part through a quasi-steady approach. The error associated with this approach is quantified as a function of the rate of change of the saturation temperature

Can resistive breathing injure the lung? Implications for COPD exacerbations

Directory of Open Access Journals (Sweden)

Vassilakopoulos T

2016-09-01

Full Text Available Theodoros Vassilakopoulos, Dimitrios Toumpanakis Pulmonary and Critical Care Medicine, Medical School, National and Kapodistrian University of Athens, Greece Abstract: In obstructive lung diseases, airway inflammation leads to bronchospasm and thus resistive breathing, especially during exacerbations. This commentary discusses experimental evidence that resistive breathing per se (the mechanical stimulus in the absence of underlying airway inflammation leads to lung injury and inflammation (mechanotransduction. The potential implications of resistive breathing-induced mechanotrasduction in COPD exacerbations are presented along with the available clinical evidence. Keywords: resistive breathing, COPD, mechanotransduction, bronchoconstriction, inflammation

Can audio coached 4D CT emulate free breathing during the treatment course?

DEFF Research Database (Denmark)

Persson, Gitte F; Nygaard, Ditte E; Olsen, Mikael

2008-01-01

BACKGROUND: The image quality of 4DCT depends on breathing regularity. Respiratory audio coaching may improve regularity and reduce motion artefacts. We question the safety of coached planning 4DCT without coaching during treatment. We investigated the possibility of coaching to a more stable...... breathing without changing the breathing amplitude. The interfraction variation of the breathing cycle amplitude in free and coached breathing was studied as well as the possible impact of fatigue on longer coaching sessions. METHODS: Thirteen volunteers completed respiratory audio coaching on 3 days within...... a 2 week period. An external marker system monitoring the motion of the thoraco-abdominal wall was used to track the respiration. On all days, free breathing and two coached breathing curves were recorded. We assumed that free versus coached breathing from day 1 (reference session) simulated breathing...

Use of fundamental condensation heat transfer experiments for the development of a sub-grid liquid jet condensation model

Energy Technology Data Exchange (ETDEWEB)

Buschman, Francis X., E-mail: Francis.Buschman@unnpp.gov; Aumiller, David L.

2017-02-15

Highlights: • Direct contact condensation data on liquid jets up to 1.7 MPa in pure steam and in the presence of noncondensable gas. • Identified a pressure effect on the impact of noncondensables to suppress condensation heat transfer not captured in existing data or correlations. • Pure steam data is used to develop a new correlation for condensation heat transfer on subcooled liquid jets. • Noncondensable data used to develop a modification to the renewal time estimate used in the Young and Bajorek correlation for condensation suppression in the presence of noncondensables. • A jet injection boundary condition, using a sub-grid jet condensation model, is developed for COBRA-IE which provides a more detailed estimate of the condensation rate on the liquid jet and allows the use of jet specific closure relationships. - Abstract: Condensation on liquid jets is an important phenomenon for many different facets of nuclear power plant transients and analyses such as containment spray cooling. An experimental facility constructed at the Pennsylvania State University, the High Pressure Liquid Jet Condensation Heat Transfer facility (HPLJCHT), has been used to perform steady-state condensation heat transfer experiments in which the temperature of the liquid jet is measured at different axial locations allowing the condensation rate to be determined over the jet length. Test data have been obtained in a pure steam environment and with varying concentrations of noncondensable gas. This data extends the available jet condensation data from near atmospheric pressure up to a pressure of 1.7 MPa. An empirical correlation for the liquid side condensation heat transfer coefficient has been developed based on the data obtained in pure steam. The data obtained with noncondensable gas were used to develop a correlation for the renewal time as used in the condensation suppression model developed by Young and Bajorek. This paper describes a new sub-grid liquid jet

Use of fundamental condensation heat transfer experiments for the development of a sub-grid liquid jet condensation model

International Nuclear Information System (INIS)

Buschman, Francis X.; Aumiller, David L.

2017-01-01

Highlights: • Direct contact condensation data on liquid jets up to 1.7 MPa in pure steam and in the presence of noncondensable gas. • Identified a pressure effect on the impact of noncondensables to suppress condensation heat transfer not captured in existing data or correlations. • Pure steam data is used to develop a new correlation for condensation heat transfer on subcooled liquid jets. • Noncondensable data used to develop a modification to the renewal time estimate used in the Young and Bajorek correlation for condensation suppression in the presence of noncondensables. • A jet injection boundary condition, using a sub-grid jet condensation model, is developed for COBRA-IE which provides a more detailed estimate of the condensation rate on the liquid jet and allows the use of jet specific closure relationships. - Abstract: Condensation on liquid jets is an important phenomenon for many different facets of nuclear power plant transients and analyses such as containment spray cooling. An experimental facility constructed at the Pennsylvania State University, the High Pressure Liquid Jet Condensation Heat Transfer facility (HPLJCHT), has been used to perform steady-state condensation heat transfer experiments in which the temperature of the liquid jet is measured at different axial locations allowing the condensation rate to be determined over the jet length. Test data have been obtained in a pure steam environment and with varying concentrations of noncondensable gas. This data extends the available jet condensation data from near atmospheric pressure up to a pressure of 1.7 MPa. An empirical correlation for the liquid side condensation heat transfer coefficient has been developed based on the data obtained in pure steam. The data obtained with noncondensable gas were used to develop a correlation for the renewal time as used in the condensation suppression model developed by Young and Bajorek. This paper describes a new sub-grid liquid jet

Improved ROS defense in the swimbladder of a facultative air-breathing erythrinid fish, jeju, compared to a non-air-breathing close relative, traira.

Science.gov (United States)

Pelster, Bernd; Giacomin, Marina; Wood, Chris M; Val, Adalberto L

2016-07-01

The jeju Hoplerythrinus unitaeniatus and the traira Hoplias malabaricus are two closely related erythrinid fish, both possessing a two-chambered physostomous swimbladder. In the jeju the anterior section of the posterior bladder is highly vascularized and the swimbladder is used for aerial respiration; the traira, in turn, is a water-breather that uses the swimbladder as a buoyancy organ and not for aerial oxygen uptake. Observation of the breathing behavior under different levels of water oxygenation revealed that the traira started aquatic surface respiration only under severe hypoxic conditions and did not breathe air. In the jeju air-breathing behavior was observed under normoxic conditions, and the frequency of air-breathing was significantly increased under hypoxic conditions. Unexpectedly, even under hyperoxic conditions (30 mg O2 L(-1)) the jeju continued to take air breaths, and compared with normoxic conditions the frequency was not reduced. Because the frequently air-exposed swimbladder tissue faces higher oxygen partial pressures than normally experienced by other fish tissues, it was hypothesized that in the facultative air-breathing jeju, swimbladder tissue would have a higher antioxidative capacity than the swimbladder tissue of the water breathing traira. Measurement of total glutathione (GSSG/GSH) concentration in anterior and posterior swimbladder tissue revealed a higher concentration of this antioxidant in swimbladder tissue as compared to muscle tissue in the jeju. Furthermore, the GSSG/GSH concentration in jeju tissues was significantly higher than in traira tissues. Similarly, activities of enzymes involved in the breakdown of reactive oxygen species were significantly higher in the jeju swimbladder as compared to the traira swimbladder. The results show that the jeju, using the swimbladder as an additional breathing organ, has an enhanced antioxidative capacity in the swimbladder as compared to the traira, using the swimbladder only as a

Computations for a condenser. Experimental results

International Nuclear Information System (INIS)

Walden, Jean.

1975-01-01

Computations for condensers are presented with experimental results. The computations are concerned with the steam flux at the condenser input, and inside the tube bundle. Experimental results are given for the flux inside the condenser sleeve and the flow passing through the tube bundle [fr

Charge Screening in a Charged Condensate

International Nuclear Information System (INIS)

Gabadadze, Gregory; Rosen, Rachel A.

2009-01-01

We consider a highly dense system of helium-4 nuclei and electrons in which the helium-4 nuclei have condensed. We present the condensation mechanism in the framework of low energy effective field theory and discuss the screening of electric charge in the condensate.

Optimization of imaging before pulmonary vein isolation by radiofrequency ablation: breath-held ungated versus ECG/breath-gated MRA

Energy Technology Data Exchange (ETDEWEB)

Allgayer, C.; Haller, S.; Bremerich, J. [University Hospital Basel, Department of Radiology, Basel (Switzerland); Zellweger, M.J.; Sticherling, C.; Buser, P.T. [University Hospital Basel, Department of Cardiology, Basel (Switzerland); Weber, O. [University Hospital Basel, Department of Medical Physics, Basel (Switzerland)

2008-12-15

Isolation of the pulmonary veins has emerged as a new therapy for atrial fibrillation. Pre-procedural magnetic resonance (MR) imaging enhances safety and efficacy; moreover, it reduces radiation exposure of the patients and interventional team. The purpose of this study was to optimize the MR protocol with respect to image quality and acquisition time. In 31 patients (23-73 years), the anatomy of the pulmonary veins, left atrium and oesophagus was assessed on a 1.5-Tesla scanner with four different sequences: (1) ungated two-dimensional true fast imaging with steady precession (2D-TrueFISP), (2) ECG/breath-gated 3D-TrueFISP, (3) ungated breath-held contrast-enhanced three-dimensional turbo fast low-angle shot (CE-3D-tFLASH), and (4) ECG/breath-gated CE-3D-TrueFISP. Image quality was scored from 1 (structure not visible) to 5 (excellent visibility), and the acquisition time was monitored. The pulmonary veins and left atrium were best visualized with CE-3D-tFLASH (scores 4.50 {+-} 0.52 and 4.59 {+-} 0.43) and ECG/breath-gated CE-3D-TrueFISP (4.47 {+-} 0.49 and 4.63 {+-} 0.39). Conspicuity of the oesophagus was optimal with CE-3D-TrueFISP and 2D-TrueFISP (4.59 {+-} 0.35 and 4.19 {+-} 0.46) but poor with CE-3D-tFLASH (1.03 {+-} 0.13) (p < 0.05). Acquisition times were shorter for 2D-TrueFISP (44 {+-} 1 s) and CE-3D-tFLASH (345 {+-} 113 s) compared with ECG/breath-gated 3D-TrueFISP (634 {+-} 197 s) and ECG/breath-gated CE-3D-TrueFISP (636 {+-} 230 s) (p < 0.05). In conclusion, an MR imaging protocol comprising CE-3D-tFLASH and 2D-TrueFISP allows assessment of the pulmonary veins, left atrium and oesophagus in less than 7 min and can be recommended for pre-procedural imaging before electric isolation of pulmonary veins. (orig.)

Breath acetone monitoring by portable Si:WO3 gas sensors

Science.gov (United States)

Righettoni, Marco; Tricoli, Antonio; Gass, Samuel; Schmid, Alex; Amann, Anton; Pratsinis, Sotiris E.

2013-01-01

Breath analysis has the potential for early stage detection and monitoring of illnesses to drastically reduce the corresponding medical diagnostic costs and improve the quality of life of patients suffering from chronic illnesses. In particular, the detection of acetone in the human breath is promising for non-invasive diagnosis and painless monitoring of diabetes (no finger pricking). Here, a portable acetone sensor consisting of flame-deposited and in situ annealed, Si-doped epsilon-WO3 nanostructured films was developed. The chamber volume was miniaturized while reaction-limited and transport-limited gas flow rates were identified and sensing temperatures were optimized resulting in a low detection limit of acetone (~20 ppb) with short response (10–15 s) and recovery times (35–70 s). Furthermore, the sensor signal (response) was robust against variations of the exhaled breath flow rate facilitating application of these sensors at realistic relative humidities (80–90%) as in the human breath. The acetone content in the breath of test persons was monitored continuously and compared to that of state-of-the-art proton transfer reaction mass spectrometry (PTR-MS). Such portable devices can accurately track breath acetone concentration to become an alternative to more elaborate breath analysis techniques. PMID:22790702

Breath-by-breath analysis of expiratory gas concentration in chickens.

Science.gov (United States)

Itabisashi, T

1981-01-01

Expiratory oxygen and carbon-dioxide concentration were analysed breath by breath in order to examine their wave forms in adult awake hens restrained in various postural positions, including supine, prone and sitting positions. Expired gas was collected at the nostril in almost all the hens. In the sitting position free from vocalization, feeding, drinking, panting, and restlessness, hens showed various forms of stable pattern of oxygen-gas curves. These forms were classified into three types, or the ascending, flat and descending types, with respect to the plateau inclination. The waves of carbon-dioxide were not always a mirror image of those of oxygen. The rate of occurrence of each type varied with the hen's postural position. The wave form was altered with the experimental body-rotation of the hen. When placed between the deflections of stable pattern, the episodes of wave deformation resembling that seen at the time of uneven pulmonary ventilation in mammals could frequently be observed in any hen's posture examined. Cardiogenic oscillation appeared on the plateau of expired-gas curves.

Polariton condensates

International Nuclear Information System (INIS)

Snoke, David; Littlewood, Peter

2010-01-01

Most students of physics know about the special properties of Bose-Einstein condensates (BECs) as demonstrated in the two best-known examples: superfluid helium-4, first reported in 1938, and condensates of trapped atomic gases, first observed in 1995. (See the article by Wolfgang Ketterle in PHYSICS TODAY, December 1999, page 30.) Many also know that superfluid 3 He and superconducting metals contain BECs of fermion pairs. An underlying principle of all those condensed-matter systems, known as quantum fluids, is that an even number of fermions with half-integer spin can be combined to make a composite boson with integer spin. Such composite bosons, like all bosons, have the property that below some critical temperature--roughly the temperature at which the thermal de Broglie wavelength becomes comparable to the distance between the bosons--the total free energy is minimized by having a macroscopic number of bosons enter a single quantum state and form a macroscopic, coherent matter wave. Remarkably, the effect of interparticle repulsion is to lead to quantum mechanical exchange interactions that make that state robust, since the exchange interactions add coherently.

Comparison of condensation correlations in CATHARE for modelling isolation condenser experiment

International Nuclear Information System (INIS)

Sorjonen, J.; Kalli, H.

1996-01-01

CATHARE is a thermal-hydraulic computer code developed at the Centre d'Etudes Nucleaires de Grenoble (CENG) for nuclear power plant safety analysis. Behaviour of a new Cathare condensation correlation have been studied. The code has been applied to Isolation Condenser (IC) experiment conducted in PIPER-ONE facility. PIPER-ONE simulates a General Electric BWR-6 with volume and height scaling ratios 1/2200 and 1/1, respectively. The facility is installed at Dipartimento di Costruzioni Meccaniche e Nucleari of Pisa University. The facility was equipped with an once-through heat exchanger immersed in a pool of ambient temperature water, installed roughly 10 m above the core, in the aim to reproduce qualitatively the phenomenologies expected for Isolation Condenser in the Simplified BWR (SBWR). Experiment PO-IC-02 included two subsequent power levels with initial pressure of 5.1 MPa. The IC was active during the whole experiment except in the time period between the two different power levels. A previous calculation of above mentioned experiment by Cathare2 V1.3E showed some lacks in the condensation correlation of the code. A new correlation has been developed in Centre d'Etudes Nucleaires de Grenoble (CENG). The new calculation of the PO-IC-02 experiment by Cathare2 Vl.3U 1 with the new correlation gave results consistent with the experiment in the condensing zone of the IC. Also the overall pressure trend was reproduced with estimated heat losses to the environment. A comparison with previously obtained Relap5/Mod3. 1 results is also shown in the present document. (author) (18 refs.)

Characterization of spacecraft humidity condensate

Science.gov (United States)

Muckle, Susan; Schultz, John R.; Sauer, Richard L.

1994-01-01

When construction of Space Station Freedom reaches the Permanent Manned Capability (PMC) stage, the Water Recovery and Management Subsystem will be fully operational such that (distilled) urine, spent hygiene water, and humidity condensate will be reclaimed to provide water of potable quality. The reclamation technologies currently baselined to process these waste waters include adsorption, ion exchange, catalytic oxidation, and disinfection. To ensure that the baseline technologies will be able to effectively remove those compounds presenting a health risk to the crew, the National Research Council has recommended that additional information be gathered on specific contaminants in waste waters representative of those to be encountered on the Space Station. With the application of new analytical methods and the analysis of waste water samples more representative of the Space Station environment, advances in the identification of the specific contaminants continue to be made. Efforts by the Water and Food Analytical Laboratory at JSC were successful in enlarging the database of contaminants in humidity condensate. These efforts have not only included the chemical characterization of condensate generated during ground-based studies, but most significantly the characterization of cabin and Spacelab condensate generated during Shuttle missions. The analytical results presented in this paper will be used to show how the composition of condensate varies amongst enclosed environments and thus the importance of collecting condensate from an environment close to that of the proposed Space Station. Although advances were made in the characterization of space condensate, complete characterization, particularly of the organics, requires further development of analytical methods.

46 CFR 56.50-35 - Condensate pumps.

Science.gov (United States)

2010-10-01

... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-35 Condensate pumps. Two means shall be provided for discharging the condensate from the main condenser, one of which shall be mechanically... suction from the condenser and a discharge to the feed tank, it may be accepted as an independent...

Gravitationally Driven Wicking for Enhanced Condensation Heat Transfer.

Science.gov (United States)

Preston, Daniel J; Wilke, Kyle L; Lu, Zhengmao; Cruz, Samuel S; Zhao, Yajing; Becerra, Laura L; Wang, Evelyn N

2018-04-17

Vapor condensation is routinely used as an effective means of transferring heat or separating fluids. Filmwise condensation is prevalent in typical industrial-scale systems, where the condensed fluid forms a thin liquid film due to the high surface energy associated with many industrial materials. Conversely, dropwise condensation, where the condensate forms discrete liquid droplets which grow, coalesce, and shed, results in an improvement in heat transfer performance of an order of magnitude compared to filmwise condensation. However, current state-of-the-art dropwise technology relies on functional hydrophobic coatings, for example, long chain fatty acids or polymers, which are often not robust and therefore undesirable in industrial conditions. In addition, low surface tension fluid condensates, such as hydrocarbons, pose a unique challenge because common hydrophobic condenser coatings used to shed water (with a surface tension of 73 mN/m) often do not repel fluids with lower surface tensions (condensation heat transfer using gravitationally driven flow through a porous metal wick, which takes advantage of the condensate's affinity to wet the surface and also eliminates the need for condensate-phobic coatings. The condensate-filled wick has a lower thermal resistance than the fluid film observed during filmwise condensation, resulting in an improved heat transfer coefficient of up to an order of magnitude and comparable to that observed during dropwise condensation. The improved heat transfer realized by this design presents the opportunity for significant energy savings in natural gas processing, thermal management, heating and cooling, and power generation.

Numerical investigation of convective condensation with the presence of non-condensable gases in a vertical tube

Energy Technology Data Exchange (ETDEWEB)

Fu, Wen [Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Li, Xiaowei, E-mail: lixiaowei@tsinghua.edu.cn [Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Wu, Xinxin [Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Corradini, Michael L. [Department of Engineering Physics, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, WI 53706 (United States)

2016-02-15

Highlights: • Gas mixture convective condensation in vertical tubes were simulated using FLUENT code. • The simulation results matched well with experimental data. • The detailed velocity field and species distribution were investigated. • The suction factors predicted by CFD models were compared with the classical correlations. • The effects of air and helium on steam condensation were compared. - Abstract: Steam condensation is degraded when non-condensable gases are present. Convective condensation of steam–air mixture and steam–helium mixture in vertical tubes were simulated using the CFD code FLUENT. The condensation process was modeled by defining source terms for the mass, momentum, species and energy conservation equations. Several cases with various steam mass fractions were simulated, the results matched well with the experimental data. Detailed velocity field and species distribution were investigated. The radial velocity was clearly represented, and the suction effect was modeled, which needs to be accounted for when using the heat and mass transfer analogy theory. The Nusselt and Sherwood numbers predicted by CFD models were compared with the classical correlations, and the suction effects were analyzed. The suction effect is proportional to steam mass fraction, while the suction factor is little affected by the Reynolds number. For forced convection flow in this work, the buoyant force can be neglected, so the larger diffusion coefficient of steam–helium mixture would improve the steam condensation compared to steam–air mixture. The condensation mass fluxes of steam–helium mixture and steam–air mixture are almost the same at relatively high steam inlet molar fraction (≥90%).

Breath acetone concentration; biological variability and the influence of diet

International Nuclear Information System (INIS)

Španěl, Patrik; Dryahina, Kseniya; Rejšková, Alžběta; Chippendale, Thomas W E; Smith, David

2011-01-01

Previous measurements of acetone concentrations in the exhaled breath of healthy individuals and the small amount of comparable data for individuals suffering from diabetes are briefly reviewed as a prelude to the presentation of new data on the sporadic and wide variations of breath acetone that occur in ostensibly healthy individuals. Data are also presented which show that following a ketogenic diet taken by eight healthy individuals their breath acetone concentrations increased up to five times over the subsequent 6 h. Similarly, the breath acetone increased six and nine times when a low carbohydrate diet was taken by two volunteers and remained high for the several days for which the diet was continued. These new data, together with the previous data, clearly indicate that diet and natural intra-individual biological and diurnal variability result in wide variations in breath acetone concentration. This places an uncertainty in the use of breath acetone alone to monitor blood glucose and glycaemic control, except and unless the individual acts as their own control and is cognizant of the need for dietary control. (note)

Fast-starting for a breath: Air breathing in Hoplosternum littorale

DEFF Research Database (Denmark)

Domenici, Paolo; Norin, Tommy; Bushnell, Peter G.

by the fall of a prey item on the water surface, and in tapping motions of goldfish, a behaviour that was interpreted to be food-related. Little is known about C-starts being used outside the context of escaping or feeding. Here, we test the hypothesis that air-breathing fish may use C-starts when gulping air...

Mapleson′s breathing systems

Directory of Open Access Journals (Sweden)

Tej K Kaul

2013-01-01

Full Text Available Mapleson breathing systems are used for delivering oxygen and anaesthetic agents and to eliminate carbon dioxide during anaesthesia. They consist of different components: Fresh gas flow, reservoir bag, breathing tubes, expiratory valve, and patient connection. There are five basic types of Mapleson system: A, B, C, D and E depending upon the different arrangements of these components. Mapleson F was added later. For adults, Mapleson A is the circuit of choice for spontaneous respiration where as Mapleson D and its Bains modifications are best available circuits for controlled ventilation. For neonates and paediatric patients Mapleson E and F (Jackson Rees modification are the best circuits. In this review article, we will discuss the structure of the circuits and functional analysis of various types of Mapleson systems and their advantages and disadvantages.

IMPLICATIONS OF MOUTH BREATHING AND ATYPICAL SWALLOWING IN BODY POSTURE

Directory of Open Access Journals (Sweden)

Veronique Sousa

2017-07-01

Conclusion: Statistically significant associations were established between the breathing pattern and the horizontal alignment of acromions, as well as the horizontal and vertical alignment of the head; between the pattern of breathing and swallowing with occlusal relationship anteroposterior and occlusal relationship vertical and also between breathing pattern and swallowing with digital sucking habits and pacifier use.

A Local Condensation Analysis Representing Two-phase Annular Flow in Condenser/radiator Capillary Tubes

Science.gov (United States)

Karimi, Amir

1991-01-01

NASA's effort for the thermal environmental control of the Space Station Freedom is directed towards the design, analysis, and development of an Active Thermal Control System (ATCS). A two phase, flow through condenser/radiator concept was baselined, as a part of the ATCS, for the radiation of space station thermal load into space. The proposed condenser rejects heat through direct condensation of ATCS working fluid (ammonia) in the small diameter radiator tubes. Analysis of the condensation process and design of condenser tubes are based on the available two phase flow models for the prediction of flow regimes, heat transfer, and pressure drops. The prediction formulas use the existing empirical relationships of friction factor at gas-liquid interface. An attempt is made to study the stability of interfacial waves in two phase annular flow. The formulation is presented of a stability problem in cylindrical coordinates. The contribution of fluid viscosity, surface tension, and transverse radius of curvature to the interfacial surface is included. A solution is obtained for Kelvin-Helmholtz instability problem which can be used to determine the critical and most dangerous wavelengths for interfacial waves.

Breath Hydrogen Produced by Ingestion of Commercial Hydrogen Water and Milk

OpenAIRE

Shimouchi, Akito; Nose, Kazutoshi; Yamaguchi, Makoto; Ishiguro, Hiroshi; Kondo, Takaharu

2009-01-01

Objective: To compare how and to what extent ingestion of hydrogen water and milk increase breath hydrogen in adults.Methods: Five subjects without specific diseases, ingested distilled or hydrogen water and milk as a reference material that could increase breath hydrogen. Their end-alveolar breath hydrogen was measured.Results: Ingestion of hydrogen water rapidly increased breath hydrogen to the maximal level of approximately 40 ppm 10–15 min after ingestion and thereafter rapidly decrease...

Running and Breathing in Mammals

Science.gov (United States)

Bramble, Dennis M.; Carrier, David R.

1983-01-01

Mechanical constraints appear to require that locomotion and breathing be synchronized in running mammals. Phase locking of limb and respiratory frequency has now been recorded during treadmill running in jackrabbits and during locomotion on solid ground in dogs, horses, and humans. Quadrupedal species normally synchronize the locomotor and respiratory cycles at a constant ratio of 1:1 (strides per breath) in both the trot and gallop. Human runners differ from quadrupeds in that while running they employ several phase-locked patterns (4:1, 3:1, 2:1, 1:1, 5:2, and 3:2), although a 2:1 coupling ratio appears to be favored. Even though the evolution of bipedal gait has reduced the mechanical constraints on respiration in man, thereby permitting greater flexibility in breathing pattern, it has seemingly not eliminated the need for the synchronization of respiration and body motion during sustained running. Flying birds have independently achieved phase-locked locomotor and respiratory cycles. This hints that strict locomotor-respiratory coupling may be a vital factor in the sustained aerobic exercise of endothermic vertebrates, especially those in which the stresses of locomotion tend to deform the thoracic complex.

Learn More Breathe Better

Centers for Disease Control (CDC) Podcasts

Chronic obstructive pulmonary disease (COPD) is a serious lung disease that makes breathing very difficult and can affect your quality of life. Learn the causes of COPD and what you can do to prevent it.

An experimental study of high pressure steam condensation in a vertical tube of passive secondary condensation system

Energy Technology Data Exchange (ETDEWEB)

Kim, Sang Jae; No, Hee Cheon [KAIST, Taejon (Korea, Republic of)

1998-07-01

To investigate the physical parameters of PSCS (Passive Secondary Condensation System) which is a passive residual heat removal system of CP-1300, the high pressure condensation experiments are performed in a small scale experimental facility. The experimental parameters are the local heat flux and the transfer coefficient and the pressure drop in a condensation heat trasnfer. The film condensation heat transfer coefficients in a vertical tube are calculated from the measured wall temperature difference and compared with the analytical models. A new analytical condensation model is developed based on the annular film flow model. The present model gives marginally better results than those from the Shah model in comparison with the experimental data in the database. Also, experimental data are compared with the results of the RELAP5/MOD3.2 thermal hydraulic code. The RELAP5/MOD3.2 underpredicts the condensation heat transfer coefficients of the present experiment by 50 %.

Condensing boiler applications in the process industry

International Nuclear Information System (INIS)

Chen, Qun; Finney, Karen; Li, Hanning; Zhang, Xiaohui; Zhou, Jue; Sharifi, Vida; Swithenbank, Jim

2012-01-01

Major challenging issues such as climate change, energy prices and fuel security have focussed the attention of process industries on their energy efficiency and opportunities for improvement. The main objective of this research study was to investigate technologies needed to exploit the large amount of low grade heat available from a flue gas condensing system through industrial condensing boilers. The technology and application of industrial condensing boilers in various heating systems were extensively reviewed. As the condensers require site-specific engineering design, a case study was carried out to investigate the feasibility (technically and economically) of applying condensing boilers in a large scale district heating system (40 MW). The study showed that by recovering the latent heat of water vapour in the flue gas through condensing boilers, the whole heating system could achieve significantly higher efficiency levels than conventional boilers. In addition to waste heat recovery, condensing boilers can also be optimised for emission abatement, especially for particle removal. Two technical barriers for the condensing boiler application are corrosion and return water temperatures. Highly corrosion-resistant material is required for condensing boiler manufacture. The thermal design of a 'case study' single pass shell-and-tube condensing heat exchanger/condenser showed that a considerable amount of thermal resistance was on the shell-side. Based on the case study calculations, approximately 4900 m 2 of total heat transfer area was required, if stainless steel was used as a construction material. If the heat transfer area was made of carbon steel, then polypropylene could be used as the corrosion-resistant coating material outside the tubes. The addition of polypropylene coating increased the tube wall thermal resistance, hence the required heat transfer area was approximately 5800 m 2 . Net Present Value (NPV) calculations showed that the choice of a carbon

Design analysis of a Helium re-condenser

Science.gov (United States)

Muley, P. K.; Bapat, S. L.; Atrey, M. D.

2017-02-01

Modern helium cryostats deploy a cryocooler with a re-condenser at its II stage for in-situ re-condensation of boil-off vapor. The present work is a vital step in the ongoing research work of design of cryocooler based 100 litre helium cryostat with in-situ re-condensation. The cryostat incorporates a two stage Gifford McMahon cryocooler having specified refrigerating capacity of 40 W at 43 K for I stage and 1 W at 4.2 K for II stage. Although design of cryostat ensures thermal load for cryocooler below its specified refrigerating capacity at the second stage, successful in-situ re-condensation depends on proper design of re-condenser which forms the objective of this work. The present work proposes design of helium re-condenser with straight rectangular fins. Fins are analyzed for optimization of thermal performance parameters such as condensation heat transfer coefficient, surface area for heat transfer, re-condensing capacity, efficiency and effectiveness. The present work provides design of re-condenser with 19 integral fins each of 10 mm height and 1.5 mm thickness with a gap of 1.5 mm between two fins, keeping in mind the manufacturing feasibility, having efficiency of 80.96 % and effectiveness of 10.34.

Fluegas condensation of domestic fuels. Kotimaisten polttoaineiden savukaasulauhdutus

Energy Technology Data Exchange (ETDEWEB)

Kankkunen, A; Fagerholm, N E

1988-01-01

The suitability of domestic fuel for condensation heat recovery was studied. With the developed computer program, enthalpies of flue gas as function of temperature were computed and also the theoretical advandages aquired by condensation were compared with different fuels. The maximal advantages of condensation were 39 % with wooden chips and 31 % with peat. The domestic fuels were found to be useful for condensation heat recovery because of the high water content and the high dewpoint of flu egas. Condensation was found to have a purifying effect on flue gases. It was found experimentaly that 30 % the sulfur of the peat dissolved to the condensed liquid. The composition of condensed liquid of peat- and wooden chip flue gases was studied to find out the corrosion and enviromental effects. The risk of corrosion to metallic heat exhanger was concluded from the compositio of peat condensat. Chip condensate was found to be almost neutral. Normally the condensate liquids were fit for sewering without aftertreatment. Heat transfer coefficient from flue gases to the wall of the condenser was measured to be 150-170 W/Km{sup 2}. Heat transfer coefficients were three times higher compared to condensing heat transfer.

Capillary-Condenser-Pumped Heat-Transfer Loop

Science.gov (United States)

Silverstein, Calvin C.

1989-01-01

Heat being transferred supplies operating power. Capillary-condenser-pumped heat-transfer loop similar to heat pipe and to capillary-evaporator-pumped heat-transfer loop in that heat-transfer fluid pumped by evaporation and condensation of fluid at heat source and sink, respectively. Capillary condenser pump combined with capillary evaporator pump to form heat exchanger circulating heat-transfer fluids in both loops. Transport of heat more nearly isothermal. Thermal stress in loop reduced, and less external surface area needed in condenser section for rejection of heat to heat sink.

A cross-sectional study of breath acetone based on diabetic metabolic disorders.

Science.gov (United States)

Li, Wenwen; Liu, Yong; Lu, Xiaoyong; Huang, Yanping; Liu, Yu; Cheng, Shouquan; Duan, Yixiang

2015-02-26

Breath acetone is a known biomarker for diabetes mellitus in breath analysis. In this work, a cross-sectional study of breath acetone based on clinical metabolic disorders of type 2 diabetes mellitus (T2DM) was carried out. Breath acetone concentrations of 113 T2DM patients and 56 apparently healthy individuals were measured at a single time point. Concentrations varied from 0.22 to 9.41 ppmv (mean 1.75 ppmv) for T2DM, which were significantly higher than those for normal controls (ranged from 0.32 to 1.96 ppmv, mean 0.72 ppmv, p = 0.008). Observations in our work revealed that breath acetone concentrations elevated to different degrees, along with the abnormality of blood glucose, glycated hemoglobin (HbA1c), triglyceride and cholesterol. Breath acetone showed obviously positive correlations with blood ketone and urine ketone. Possible metabolic relations between breath acetone and diabetic disorders were also discussed. This work aimed at giving an overall assessment of breath acetone from the perspective of clinical parameters for type 2 diabetes.

The lung cancer breath signature: a comparative analysis of exhaled breath and air sampled from inside the lungs

Science.gov (United States)

Capuano, Rosamaria; Santonico, Marco; Pennazza, Giorgio; Ghezzi, Silvia; Martinelli, Eugenio; Roscioni, Claudio; Lucantoni, Gabriele; Galluccio, Giovanni; Paolesse, Roberto; di Natale, Corrado; D'Amico, Arnaldo

2015-11-01

Results collected in more than 20 years of studies suggest a relationship between the volatile organic compounds exhaled in breath and lung cancer. However, the origin of these compounds is still not completely elucidated. In spite of the simplistic vision that cancerous tissues in lungs directly emit the volatile metabolites into the airways, some papers point out that metabolites are collected by the blood and then exchanged at the air-blood interface in the lung. To shed light on this subject we performed an experiment collecting both the breath and the air inside both the lungs with a modified bronchoscopic probe. The samples were measured with a gas chromatography-mass spectrometer (GC-MS) and an electronic nose. We found that the diagnostic capability of the electronic nose does not depend on the presence of cancer in the sampled lung, reaching in both cases an above 90% correct classification rate between cancer and non-cancer samples. On the other hand, multivariate analysis of GC-MS achieved a correct classification rate between the two lungs of only 76%. GC-MS analysis of breath and air sampled from the lungs demonstrates a substantial preservation of the VOCs pattern from inside the lung to the exhaled breath.

Emergency condensator for BWR type reactor

International Nuclear Information System (INIS)

Ubakai, Yoichi; Narumi, Yuichi; Sakata, Yuji.

1992-01-01

An emergency condensator is constituted with heat transfer pipes, a steam chamber, an upper pipe plate, a lower pipe plate and a condensate chamber. The upper pipe plate is secured by supports, and a steam pipe is connected to the upper pipe plate. A condensate pipeline and a incondensible gas vent pipe are disposed to the condensate chamber. Taking thermal expansion of the steam pipes and thermal expansion of the heat transfer pipes into consideration, the heat transfer pipe is made as an L-shaped pipe having a vertical portion and a horizontal portion so as to absorb each of the thermal expansion smoothly. The L-shaped heat transfer pipes are constituted as a bundle of pipes having the end portions thereof secured to the upper pipe plate and the lower pipe plate. The emergency condensator is disposed in a emergency condensator pool chamber. Cooling water in contact with the outer side of the L-shaped heat transfer pipes is the pool water in the pool chamber, and the condensator chamber is disposed in concrete walls of the pool chamber. With such a constitution, stress due to thermal expansion of the heat transfer pipes is mitigated, and heat transfer performance, earth quake resistance and maintenancability are improved. (I.N.)

Experimental investigation of non-condensable gases effect on operation of VVER steam generator in condensation mode

International Nuclear Information System (INIS)

Efanov, A. D.; Kalyakin, S. G.; Morozov, A. V.; Remizov, O. V.; Tsyganok, A. A.; Generalov, V. N.; Berkovich, V. M.; Taranov, G. S.

2008-01-01

To provide the safety in new Russian NPP designs, protection passive systems which don't depend upon human errors are widely used. In terms of safety, the design of NPP of new generation (NPP-2006) falls into the class of advanced NPPs. In the event of an beyond design basis accident with the rupture of the reactor primary circuit and accompanied by the loss of ac sources, the use of passive safety systems are provided for necessary core cooling. Among these is passive heat removal system (PHRS). In the case of leakage in the primary circuit this system ensures the transition of steam generators (SG) to operation in the mode of condensation of the primary circuit steam coming to SG piping from the reactor. As a result, the condensate from steam generators arrives at the core providing its additional cooling. The SG condensation capacity can be adversely affected by the presence of non-condensable gases in the primary circuit of the reactor. Their main sources are nitrogen arriving at the circuit, as hydro accumulators actuate, products of radiolysis of water and air drawn in from the containment through the pipeline rupture. The accumulation of non-condensable gases in SG piping can result in degradation of its condensation capacity to the extent that condensation completely terminates. In this case, the core cooling conditions may be impaired. To experimental investigation of the condensation mode of operation of WER steam generator, a large scale HA2M-SG test rig was constructed at the SSC RF IPPE. The test rig incorporates: buffer tank, equipped by steam supply system; SG model with volumetric-power scale is 1:46; PHRS heat exchanger imitator, cooling by process water. The rig main equipment connected by pipelines and equipped by valves. The elevations of the main equipment correspond to those of reactor project. The rig maximum operating parameters: steam pressure - 1.6 MPa, temperature - 200 Celsius degrees. Experiments at the HA2M-SG test rig have been

Noise Reduction in Breath Sound Files Using Wavelet Transform Based Filter

Science.gov (United States)

Syahputra, M. F.; Situmeang, S. I. G.; Rahmat, R. F.; Budiarto, R.

2017-04-01

The development of science and technology in the field of healthcare increasingly provides convenience in diagnosing respiratory system problem. Recording the breath sounds is one example of these developments. Breath sounds are recorded using a digital stethoscope, and then stored in a file with sound format. This breath sounds will be analyzed by health practitioners to diagnose the symptoms of disease or illness. However, the breath sounds is not free from interference signals. Therefore, noise filter or signal interference reduction system is required so that breath sounds component which contains information signal can be clarified. In this study, we designed a filter called a wavelet transform based filter. The filter that is designed in this study is using Daubechies wavelet with four wavelet transform coefficients. Based on the testing of the ten types of breath sounds data, the data is obtained in the largest SNRdB bronchial for 74.3685 decibels.

Relationship between musical characteristics and temporal breathing pattern in piano performance

Directory of Open Access Journals (Sweden)

Yutaka Sakaguchi

2016-07-01

Full Text Available Although there is growing evidence that breathing is modulated by various motor and cognitive activities, the nature of breathing in musical performance has been little explored. The present study examined the temporal breath pattern in piano performance, aiming to elucidate how breath timing is related to musical organization/events and performance. In the experiments, the respiration of 15 professional and amateur pianists, playing 10 music excerpts in total (from four-octave C major scale, Hanon’s exercise, J. S. Bach’s Invention, Mozart’s Sonatas, and Debussy’s Clair de lune, was monitored by capnography. The relationship between breathing and musical characteristics was analyzed. Five major results were obtained. 1 Mean breath interval was shortened for excerpts in faster tempi. 2 Fluctuation of breath intervals was reduced for the pieces for finger exercise and those in faster tempi. Pianists showing large within-trial fluctuation also exhibited large inter-excerpt difference. 3 Inter-trial consistency of the breath patterns depended on the excerpts. Consistency was generally reduced for the excerpts that could be performed mechanically (i.e., pieces for finger exercise, but interestingly, one third of the participant showed consistent patterns for the simple scale, correlated with the ascending/descending sequences. 4 Pianists tended to exhale just after the music onsets, inhale at the rests, and inhibit inhale during the slur parts. There was correlation between breathing pattern and two-voice polyphonic structure for several participants. 5 Respiratory patterns were notably different among the pianists. Every pianist showed his or her own characteristic features commonly for various musical works. These findings suggest that breathing in piano performance depends not only on musical parameters and organization written in the score but also some pianist-dependent factors which might be ingrained to individual pianists.

Relationship between Musical Characteristics and Temporal Breathing Pattern in Piano Performance.

Science.gov (United States)

Sakaguchi, Yutaka; Aiba, Eriko

2016-01-01

Although there is growing evidence that breathing is modulated by various motor and cognitive activities, the nature of breathing in musical performance has been little explored. The present study examined the temporal breath pattern in piano performance, aiming to elucidate how breath timing is related to musical organization/events and performance. In the experiments, the respiration of 15 professional and amateur pianists, playing 10 music excerpts in total (from four-octave C major scale, Hanon's exercise, J. S. Bach's Invention, Mozart's Sonatas, and Debussy's Clair de lune), was monitored by capnography. The relationship between breathing and musical characteristics was analyzed. Five major results were obtained. (1) Mean breath interval was shortened for excerpts in faster tempi. (2) Fluctuation of breath intervals was reduced for the pieces for finger exercise and those in faster tempi. Pianists showing large within-trial fluctuation also exhibited large inter-excerpt difference. (3) Inter-trial consistency of the breath patterns depended on the excerpts. Consistency was generally reduced for the excerpts that could be performed mechanically (i.e., pieces for finger exercise), but interestingly, one third of the participant showed consistent patterns for the simple scale, correlated with the ascending/descending sequences. (4) Pianists tended to exhale just after the music onsets, inhale at the rests, and inhibit inhale during the slur parts. There was correlation between breathing pattern and two-voice polyphonic structure for several participants. (5) Respiratory patterns were notably different among the pianists. Every pianist showed his or her own characteristic features commonly for various musical works. These findings suggest that breathing in piano performance depends not only on musical parameters and organization written in the score but also some pianist-dependent factors which might be ingrained to individual pianists.

Titanium application to power plant condensers

International Nuclear Information System (INIS)

Itoh, H.

1987-01-01

Recently, the growth of operating performance and construction plan of titanium-tubed condensers in thermal and unclear power plants has been very impressive. High-quality, thinner welded titanium tubes used for cooling tubes, matching design specifications of condensers, have been stably supplied through mass production. It now can be said that various technical problems for titanium-tubed condensers have been solved, but data on operating performance in large-scale commercial plants are still scarce, and site-by-site information needs be exchanged more frequently and on a larger scale. Projects to replace existing condenser cooling tubes with those of corrosion-resistant titanium have been actively furthered, with the only remaining barrier to full employment being cost effectiveness. It is hoped that condenser and tube manufacturers will conduct more joint value analyses

Bose Condensate in He II

International Nuclear Information System (INIS)

Svensson, E.C.

1984-01-01

The Condensate Saga, now halfway through its fifth decade, is reviewed. The recent neutron-scattering work which has at last convincingly established that there is indeed a Bose Condensate in He II is described

Sleep-disordered breathing and mortality: a prospective cohort study.

OpenAIRE

Naresh M Punjabi; Brian S Caffo; James L Goodwin; Daniel J Gottlieb; Anne B Newman; George T O'Connor; David M Rapoport; Susan Redline; Helaine E Resnick; John A Robbins; Eyal Shahar; Mark L Unruh; Jonathan M Samet

2009-01-01

Editors' Summary Background About 1 in 10 women and 1 in 4 men have a chronic condition called sleep-disordered breathing although most are unaware of their problem. Sleep-disordered breathing, which is commonest in middle-aged and elderly people, is characterized by numerous, brief (10 second or so) interruptions of breathing during sleep. These interruptions, which usually occur when relaxation of the upper airway muscles decreases airflow, lower the level of oxygen in the blood and, as a r...

Modelling of film condensation in presence of non condensable gases

International Nuclear Information System (INIS)

Genevieve Geffraye; Dominique Bestion; Vladimir Kalitvianski

2005-01-01

Full text of publication follows: This paper presents recent developments in the modelling of the condensation due to heat removal from a wall with a possible presence of hydrogen, nitrogen, or air. This work is mainly concerned with nuclear reactor safety with particular reference to situations related to new reactor design, cold shutdown state and severe accident analysis. Film condensation of steam in presence of nitrogen and helium in a tube has been investigated in the COTURNE experiment in a rather large range of parameters, pressure (from 0.1 to 7 Mpa), heat flux (0.1 to 6 W/cm 2 ), mass fraction of noncondensable gas (0 to 1) and also in presence of superheated steam. The experiment represents a Steam Generator tube of a Pressurised Water Reactor and can simulate both co-current or countercurrent flow of steam and water.The models are implemented in the CATHARE code used for nuclear reactor thermal-hydraulics. The code uses two mass balance equations for liquid and gas, two momentum balance equations for liquid and gas and two energy balance equations for liquid and gas. Additional mass transport equations can be added for each non condensable gas. Heat transfers from wall to liquid film, from liquid to interface and gas to interface are modelled. The liquid film heat transfer coefficient is first investigated in pure saturated steam conditions in the pressure range from 0.1 to 7 Mpa. The CATHARE film condensation model in pure steam conditions is derived from Chen's correlation. Chen proposes a general correlation for the film condensation, covering the wavy-laminar and the turbulent film regimes and taking into account the interfacial friction effect. A large data base of laminar film regime was used including COTURNE data other available data found in the literature. The analysis of these data base suggests an influence of the liquid Reynolds number, according to the Nusselt theory, and also of the Eoetvoes number, with surface tension effects. A

Impact of breath holding on cardiovascular respiratory and cerebrovascular health.

Science.gov (United States)

Dujic, Zeljko; Breskovic, Toni

2012-06-01

Human underwater breath-hold diving is a fascinating example of applied environmental physiology. In combination with swimming, it is one of the most popular forms of summer outdoor physical activities. It is performed by a variety of individuals ranging from elite breath-hold divers, underwater hockey and rugby players, synchronized and sprint swimmers, spear fishermen, sponge harvesters and up to recreational swimmers. Very few data currently exist concerning the influence of regular breath holding on possible health risks such as cerebrovascular, cardiovascular and respiratory diseases. A literature search of the PubMed electronic search engine using keywords 'breath-hold diving' and 'apnoea diving' was performed. This review focuses on recent advances in knowledge regarding possibly harmful physiological changes and/or potential health risks associated with breath-hold diving. Available evidence indicates that deep breath-hold dives can be very dangerous and can cause serious acute health problems such a collapse of the lungs, barotrauma at descent and ascent, pulmonary oedema and alveolar haemorrhage, cardiac arrest, blackouts, nitrogen narcosis, decompression sickness and death. Moreover, even shallow apnoea dives, which are far more frequent, can present a significant health risk. The state of affairs is disturbing as athletes, as well as recreational individuals, practice voluntary apnoea on a regular basis. Long-term health risks of frequent maximal breath holds are at present unknown, but should be addressed in future research. Clearly, further studies are needed to better understand the mechanisms related to the possible development or worsening of different clinical disorders in recreational or competitive breath holding and to determine the potential changes in training/competition regimens in order to prevent these adverse events.

21 CFR 868.5260 - Breathing circuit bacterial filter.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing circuit bacterial filter. 868.5260 Section 868.5260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... filter. (a) Identification. A breathing circuit bacterial filter is a device that is intended to remove...

QCD condensates in ADS/QCD

DEFF Research Database (Denmark)

Bechi, Jacopo

2009-01-01

This paper focuses on some issues about condensates and renormalization in AdS/QCD models. In particular we consider the consistency of the AdS/QCD approach for scale dependent quantities as the chiral condensate questioned in some recent papers and the 4D meaning of the 5D cosmological constant...... in a model in which the QCD is dual to a 5D gravity theory. We will be able to give some arguments that the cosmological constant is related to the QCD gluon condensate....

Bose condensation in (random traps

Directory of Open Access Journals (Sweden)

V.A. Zagrebnov

2009-01-01

Full Text Available We study a non-interacting (perfect Bose-gas in random external potentials (traps. It is shown that a generalized Bose-Einstein condensation in the random eigenstates manifests if and only if the same occurs in the one-particle kinetic-energy eigenstates, which corresponds to the generalized condensation of the free Bose-gas. Moreover, we prove that the amounts of both condensate densities are equal. This statement is relevant for justification of the Bogoliubov approximation} in the theory of disordered boson systems.

14C-urea breath test for the detection of Helicobacter pylori

International Nuclear Information System (INIS)

Veldhuyzen van Zanten, S.J.; Tytgat, K.M.; Hollingsworth, J.; Jalali, S.; Rshid, F.A.; Bowen, B.M.; Goldie, J.; Goodacre, R.L.; Riddell, R.H.; Hunt, R.H.

1990-01-01

The high urease activity of Helicobacter pylori can be used to detect this bacterium by noninvasive breath tests. We have developed a 14 C-urea breath test which uses 5 microCi 14 C with 50 mg nonradioactive urea. Breath samples are collected at baseline and every 30 min for 2 h. Our study compared the outcome of the breath test to the results of histology and culture of endoscopically obtained gastric biopsies in 84 patients. The breath test discriminated well between the 50 positive patients and the 34 patients negative for Helicobacter pylori: the calculated sensitivity was 100%, specificity 88%, positive predictive value 93%, and negative predictive value 100%. Treatment with bismuth subsalicylate and/or ampicillin resulted in lower counts of exhaled 14 CO 2 which correlated with histological improvement in gastritis. The 14 C-urea breath test is a better gold standard for the detection of Helicobacter pylori than histology and/or culture

Condensed matter physics

CERN Document Server

Isihara, A

2007-01-01

More than a graduate text and advanced research guide on condensed matter physics, this volume is useful to plasma physicists and polymer chemists, and their students. It emphasizes applications of statistical mechanics to a variety of systems in condensed matter physics rather than theoretical derivations of the principles of statistical mechanics and techniques. Isihara addresses a dozen different subjects in separate chapters, each designed to be directly accessible and used independently of previous chapters. Topics include simple liquids, electron systems and correlations, two-dimensional

Apparatus and method for monitoring breath acetone and diabetic diagnostics

Science.gov (United States)

Duan, Yixiang [Los Alamos, NM; Cao, Wenqing [Los Alamos, NM

2008-08-26

An apparatus and method for monitoring diabetes through breath acetone detection and quantitation employs a microplasma source in combination with a spectrometer. The microplasma source provides sufficient energy to produce excited acetone fragments from the breath gas that emit light. The emitted light is sent to the spectrometer, which generates an emission spectrum that is used to detect and quantify acetone in the breath gas.

Measuring breath acetone for monitoring fat loss: Review.

Science.gov (United States)

Anderson, Joseph C

2015-12-01

Endogenous acetone production is a by-product of the fat metabolism process. Because of its small size, acetone appears in exhaled breath. Historically, endogenous acetone has been measured in exhaled breath to monitor ketosis in healthy and diabetic subjects. Recently, breath acetone concentration (BrAce) has been shown to correlate with the rate of fat loss in healthy individuals. In this review, the measurement of breath acetone in healthy subjects is evaluated for its utility in predicting fat loss and its sensitivity to changes in physiologic parameters. BrAce can range from 1 ppm in healthy non-dieting subjects to 1,250 ppm in diabetic ketoacidosis. A strong correlation exists between increased BrAce and the rate of fat loss. Multiple metabolic and respiratory factors affect the measurement of BrAce. BrAce is most affected by changes in the following factors (in descending order): dietary macronutrient composition, caloric restriction, exercise, pulmonary factors, and other assorted factors that increase fat metabolism or inhibit acetone metabolism. Pulmonary factors affecting acetone exchange in the lung should be controlled to optimize the breath sample for measurement. When biologic factors are controlled, BrAce measurement provides a non-invasive tool for monitoring the rate of fat loss in healthy subjects. © 2015 The Authors Obesity published by Wiley Periodicals, Inc. on behalf of The Obesity Society (TOS).

Condensed tannins: Base-catalysed reactions of polymeric procyanidins with toluene-α-thiol, liability of the interflavanoid bond and pyran ring

Science.gov (United States)

Peter E. Laks; Richard W. Hemingway

1987-01-01

Reaction of polymeric procyanidins (condensed tannins) with toluene-α-thiol at pH 12.0 and 23°C gave predominantly one stereoisomer of 1.3-bisbenzylthio-1-(3,4-dihydroxyphenyl)-3-(2,4,6-trihydroxyphenyl) propan-2-ol (10) by stereoselective reaction at C-4 and C-2 of the Quinone methide derived from the upper 2,3-cis procyanidin units....

Dual approaches for defects condensation

Energy Technology Data Exchange (ETDEWEB)

Rougemont, Romulo; Grigorio, Leonardo de Souza; Wotzasek, Clovis [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Guimaraes, Marcelo Santos [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil)

2009-07-01

Full text. Due to the fact that the QCD running coupling constant becomes larger as we go into the low energy (or large distance) limit of the theory, a perturbative treatment of its infrared (IR) region is impossible. In particular, a formal mathematical demonstration of color confinement and a complete physical understanding of the exact mechanism that confines quarks and gluons are two missing points in our current knowledge of the IR-QCD. It was known that due to the Meissner effect of expulsion of magnetic fields in a electric condensate that usual superconductors should confine magnetic monopoles. That point led to the conjecture that the QCD vacuum could be a condensate of chromomagnetic monopoles, a dual superconductor (DSC). Such a chromomagnetic condensate should be responsible for the dual Meissner effect which is expected to lead to the confinement of color charges immersed in this medium. In dual superconductor models of color confinement, magnetic monopoles appear as topological defects in points of the space where the abelian projection becomes singular. Also, condensation of other kinds of defects such as vortices in superfluids and line-like defects in solids are responsible for a great variety of phase transitions, which once more proves the relevance of the subject. In the present work we review two methods that allow us to approach the condensation of defects: the Kleinert Mechanism (KM) and the Julia-Toulouse Mechanism (JTM). We show that in the limit where the vortex gauge field goes to zero, which we identify as the signature of the condensation of defects in the dual picture, these are two equivalent dual prescriptions for obtaining an effective theory for a phase where defects are condensed, starting from the fundamental theory defined in the normal phase where defects are diluted. (author)

14C-urea breath test in the detection of Helicobacter pylori infection

International Nuclear Information System (INIS)

Artiko, V.M.; Obradovic, V.B.; Petrovic, N.S.; Davidovic, B.M.; Grujic-Adanja, G.S.; Nastic-Miric, D.R.; Milosavljevic, T.N.

2001-01-01

Helicobacter pylori infection is supposed to be one of the major causes of digestive and other diseases. Among a lot of invasive and non-invasive methods for its detection, none is ideal. The aim is an assessment of the Helicobacter pylori infection in the stomach using breath test and comparison to other diagnostic methods, as well as following up the effects of therapy. In 17 patients with digestive discomfort, breath test, rapid urease test and histology were performed, while in 47 patients with proven HP infection the effect of therapy was followed up using breath test and clinical findings. Breath test was performed after per oral administration of the capsule of 14 C urea (37 kBq). Findings of the breath and urease tests were in accordance in 14/17 patients (83%) while breath test and histology in 16/17 patients (94%). During follow-up of the therapeutic effects, breath test and clinical findings were in accordance in 43/47 patients (98%). Breath test can be useful in diagnosis but is a method of choice in following up the patients after therapy for H. pylori infection, because it is non-invasive, fast and precise. (author)

Measurement and prediction of indoor air quality using a breathing thermal manikin.

Science.gov (United States)

Melikov, A; Kaczmarczyk, J

2007-02-01

The analyses performed in this paper reveal that a breathing thermal manikin with realistic simulation of respiration including breathing cycle, pulmonary ventilation rate, frequency and breathing mode, gas concentration, humidity and temperature of exhaled air and human body shape and surface temperature is sensitive enough to perform reliable measurement of characteristics of air as inhaled by occupants. The temperature, humidity, and pollution concentration in the inhaled air can be measured accurately with a thermal manikin without breathing simulation if they are measured at the upper lip at a distance of measured inhaled air parameters. Proper simulation of breathing, especially of exhalation, is needed for studying the transport of exhaled air between occupants. A method for predicting air acceptability based on inhaled air parameters and known exposure-response relationships established in experiments with human subjects is suggested. Recommendations for optimal simulation of human breathing by means of a breathing thermal manikin when studying pollution concentration, temperature and humidity of the inhaled air as well as the transport of exhaled air (which may carry infectious agents) between occupants are outlined. In order to compare results obtained with breathing thermal manikins, their nose and mouth geometry should be standardized.

Development of balanced downflow type surface condensers, (2)

International Nuclear Information System (INIS)

Tomida, Akira; Oshima, Yoshikuni; Okochi, Isao; Izumi, Kenkichi.

1976-01-01

As the size of the condensers for power generation plants grew large, the new balanced downflow type condenser was developed and completed on the basis of the experiment on steam flow according to the two-dimensional flow model, the analysis of the performance in a tube nest with a computer, and the studies on the effect of outside liquid film and the reheating deaeration of condensate. When the balanced downflow type condensers were adopted for actual plants, the construction, strength and production method were examined, and the reliability of the new condenser was confirmed by the thermal characteristic experiment with the model similar to the actual machine. The condenser comprises a condenser body, supporting plates, cooling tubes, tube plates, water chambers, and reinforcements, and the cooling tubes are arranged so as to exchange heat effectively. The arrangement of tubes is divided into three regions, namely radiation portion, densely arranged portion, and air cooling portion. In the balanced downflow type condensers, the dilution by utilizing condensate is provided against ammonia attack. The apparatuses for the thermal characteristic experiment and the experimental results, and the results of the performance test on the actual balanced downflow type condenser are reported. (Kako, I.)

A Study on Condensation Heat Transfer at the Exterior Surface of S.A.M. Coated Titanium Tube Using in Steam Condensers

Energy Technology Data Exchange (ETDEWEB)

Im, Sung-Gu; Lee, Sang-Hyup; Ji, Dae-Yun; Park, Hyun-Gyu; Lee, Kwon-Yeong [Handong Global University, Pohang (Korea, Republic of)

2016-10-15

Condensation occurs when the temperature of a steam is reduced below its saturation temperature. There exist two forms of condensation on cooling surface: dropwise, and film condensations. Usually, dropwise condensation has a better heat transfer performance than film condensation, but it has limit of short period. Ma et al. executed heat transfer experiment in dropwise condensation with non-condensable gas, and studied how the amount of air and pressure difference affect condensation heat transfer coefficient. The more non-condensable gas exist, the condensation heat transfer coefficient is decreased. As a result, surface modified brass tube and stainless tube showed higher condensation heat transfer coefficient as much as 1.3 and 1.4 times comparing with their bare tubes in 70 kPa vacuum condition respectively. Most of power plants use sea water as coolant, so the surface of metal tubes could be corroded by the coolant. We had researched an experimental study related to condensation heat transfer on surface modified titanium tube. Our experimental facility was designed to show how two kinds of tube's heat transfer performances are different in a same condition. We changed the range of saturation pressure and coolant flow rate to observe tube's performance change. When saturation pressure and coolant flow rate increase, overall heat transfer coefficients were increased. When residue of non-condensable gases was decreased, the overall heat transfer coefficients were increased. S.A.M. coated tube's overall heat transfer coefficients were lower than those of bare tube, because the droplets didn't have a tendency of frequently falling down.

Sleep disordered breathing in spinal cord injury: A systematic review.

Science.gov (United States)

Chiodo, Anthony E; Sitrin, Robert G; Bauman, Kristy A

2016-07-01

Spinal cord injury commonly results in neuromuscular weakness that impacts respiratory function. This would be expected to be associated with an increased likelihood of sleep-disordered breathing. (1) Understand the incidence and prevalence of sleep disordered breathing in spinal cord injury. (2) Understand the relationship between injury and patient characteristics and the incidence of sleep disordered breathing in spinal cord injury. (3) Distinguish between obstructive sleep apnea and central sleep apnea incidence in spinal cord injury. (4) Clarify the relationship between sleep disordered breathing and stroke, myocardial infarction, metabolic dysfunction, injuries, autonomic dysreflexia and spasticity incidence in persons with spinal cord injury. (5) Understand treatment tolerance and outcome in persons with spinal cord injury and sleep disordered breathing. Extensive database search including PubMed, Cochrane Library, CINAHL and Web of Science. Given the current literature limitations, sleep disordered breathing as currently defined is high in patients with spinal cord injury, approaching 60% in motor complete persons with tetraplegia. Central apnea is more common in patients with tetraplegia than in patients with paraplegia. Early formal sleep study in patients with acute complete tetraplegia is recommended. In patients with incomplete tetraplegia and with paraplegia, the incidence of sleep-disordered breathing is significantly higher than the general population. With the lack of correlation between symptoms and SDB, formal study would be reasonable. There is insufficient evidence in the literature on the impact of treatment on morbidity, mortality and quality of life outcomes.

Methodological aspects of breath hydrogen (H2) analysis. Evaluation of a H2 monitor and interpretation of the breath H2 test

DEFF Research Database (Denmark)

Rumessen, J J; Kokholm, G; Gudmand-Høyer, E

1987-01-01

The reliability of end-expiratory hydrogen (H2) breath tests were assessed and the significance of some important pitfalls were studied, using a compact, rapid H2-monitor with electrochemical cells. The H2 response was shown to be linear and stable. The reproducibility of the breath collection...... were studied in 10 healthy adults during a 4-month period and they showed very marked inter- and intra-individual variability (16% above 40 p.p.m.). Initial peaks (early, short-lived H2 rises unrelated to carbohydrate malabsorption) were identified in 25% of the breath tests (in 4% above 20 p.......p.m). It is concluded that the technique used for interval sampling of end-expiratory breath samples for H2 concentration gives reliable results. The biological significance of H2 concentration increments can only be evaluated if the limitations of the technical procedures and the individual ability to produce H2...

Fermion condensation and gapped domain walls in topological orders

Energy Technology Data Exchange (ETDEWEB)

Wan, Yidun [Department of Physics and Center for Field Theory and Particle Physics, Fudan University,Shanghai 200433 (China); Collaborative Innovation Center of Advanced Microstructures, Nanjing University,Nanjing 210093 (China); Perimeter Institute for Theoretical Physics,Waterloo N2L 2Y5, Ontario (Canada); Wang, Chenjie [Perimeter Institute for Theoretical Physics,Waterloo N2L 2Y5, Ontario (Canada)

2017-03-31

We study fermion condensation in bosonic topological orders in two spatial dimensions. Fermion condensation may be realized as gapped domain walls between bosonic and fermionic topological orders, which may be thought of as real-space phase transitions from bosonic to fermionic topological orders. This picture generalizes the previous idea of understanding boson condensation as gapped domain walls between bosonic topological orders. While simple-current fermion condensation was considered before, we systematically study general fermion condensation and show that it obeys a Hierarchy Principle: a general fermion condensation can always be decomposed into a boson condensation followed by a minimal fermion condensation. The latter involves only a single self-fermion that is its own anti-particle and that has unit quantum dimension. We develop the rules of minimal fermion condensation, which together with the known rules of boson condensation, provides a full set of rules for general fermion condensation.

A computer code (MONA) for pH and chemistry evaluation in the secondary system water of PWR

International Nuclear Information System (INIS)

Nordmann, F.

1983-01-01

Many corrosion phenomena of the PWR secondary system materials, strongly depend on the pH of the fluid. On operating plants, only room temperature pH of the bulk water can be measured. The knowledge of the pH at the operating temperature and its relationship with the measured value is therefore particularly interesting. In addition, an evaluation of the local chemistry in flow-restricted areas of the steam generator (SG) where drastic corrosion generally occurs, is of utmost concern. The MONA code has been developed to compute the secondary water pH in the following cases: at temperatures ranging from 0 to 320 deg C; at any concentration of ammonia; at any amount of pollutants such as sea water, river water (from condenser leak), and/or sodium, chloride, sulfate (from demineralization resins); with possible addition of calcium hydroxide or boric acid in order to inhibit denting or intergranular attack. (author)

The Breath of Chemistry

DEFF Research Database (Denmark)

Josephsen, Jens

The present preliminary text is a short thematic presentation in biological inorganic chemistry meant to illustrate general and inorganic (especially coordination) chemistry in biochemistry. The emphasis is on molecular models to explain features of the complicated mechanisms essential to breathing...

Models of coherent exciton condensation

International Nuclear Information System (INIS)

Littlewood, P B; Eastham, P R; Keeling, J M J; Marchetti, F M; Simons, B D; Szymanska, M H

2004-01-01

That excitons in solids might condense into a phase-coherent ground state was proposed about 40 years ago, and has been attracting experimental and theoretical attention ever since. Although experimental confirmation has been hard to come by, the concepts released by this phenomenon have been widely influential. This tutorial review discusses general aspects of the theory of exciton and polariton condensates, focusing on the reasons for coherence in the ground state wavefunction, the BCS to Bose crossover(s) for excitons and for polaritons, and the relationship of the coherent condensates to standard lasers

Models of coherent exciton condensation

Energy Technology Data Exchange (ETDEWEB)

Littlewood, P B [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Eastham, P R [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Keeling, J M J [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Marchetti, F M [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Simons, B D [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Szymanska, M H [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom)

2004-09-08

That excitons in solids might condense into a phase-coherent ground state was proposed about 40 years ago, and has been attracting experimental and theoretical attention ever since. Although experimental confirmation has been hard to come by, the concepts released by this phenomenon have been widely influential. This tutorial review discusses general aspects of the theory of exciton and polariton condensates, focusing on the reasons for coherence in the ground state wavefunction, the BCS to Bose crossover(s) for excitons and for polaritons, and the relationship of the coherent condensates to standard lasers.

Cardio-metabolic Diseases Prevention by Self-monitoring the Breath

Directory of Open Access Journals (Sweden)

Danila GERMANESE

2017-08-01

Full Text Available As new as very promising technique, breath analysis allows for monitoring the biochemical processes that occur in human body in a non-invasive way. Nevertheless, the high costs for standard analytical instrumentation (i.e., gas chromatograph, mass spectrometer, the need for specialized personnel able to read the results and the lack of protocols to collect breath samples, set limit to the exploitation of breath analysis in clinical practice. Here, we describe the development of a device, named Wize Sniffer, which is portable and entirely based on low cost technology: it uses an array of commercial, semiconductor gas sensors and a widely employed open source controller, an Arduino Mega2560 with Ethernet module. In addition, it is very easy-to-use also for non-specialized personnel and able to analyze in real time the composition of the breath. The Wize Sniffer is composed of three modules: signal measurement module, signal conditioning module and signal processing module. The idea was born in the framework of European SEMEiotic Oriented Technology for Individual's CardiOmetabolic risk self-assessmeNt and Self-monitoring (SEMEOTICONS Project, in order to monitor individual's lifestyle by detecting in the breath those molecules related to the noxious habits for cardio-metabolic risk (alcohol intake, smoking, wrong diet. Nonetheless, the modular configuration of the device allows for changing the sensors according to the molecules to be detected, thus fully exploiting the potential of breath analysis.

Transition in organ function during the evolution of air-breathing; insights from Arapaima gigas, an obligate air-breathing teleost from the Amazon.

Science.gov (United States)

Brauner, C J; Matey, V; Wilson, J M; Bernier, N J; Val, A L

2004-04-01

The transition from aquatic to aerial respiration is associated with dramatic physiological changes in relation to gas exchange, ion regulation, acid-base balance and nitrogenous waste excretion. Arapaima gigas is one of the most obligate extant air-breathing fishes, representing a remarkable model system to investigate (1) how the transition from aquatic to aerial respiration affects gill design and (2) the relocation of physiological processes from the gills to the kidney during the evolution of air-breathing. Arapaima gigas undergoes a transition from water- to air-breathing during development, resulting in striking changes in gill morphology. In small fish (10 g), the gills are qualitatively similar in appearance to another closely related water-breathing fish (Osteoglossum bicirrhosum); however, as fish grow (100-1000 g), the inter-lamellar spaces become filled with cells, including mitochondria-rich (MR) cells, leaving only column-shaped filaments. At this stage, there is a high density of MR cells and strong immunolocalization of Na(+)/K(+)-ATPase along the outer cell layer of the gill filament. Despite the greatly reduced overall gill surface area, which is typical of obligate air-breathing fish, the gills may remain an important site for ionoregulation and acid-base regulation. The kidney is greatly enlarged in A. gigas relative to that in O. bicirrhosum and may comprise a significant pathway for nitrogenous waste excretion. Quantification of the physiological role of the gill and the kidney in A. gigas during development and in adults will yield important insights into developmental physiology and the evolution of air-breathing.

Comparison of two single-breath-held 3-D acquisitions with multi-breath-held 2-D cine steady-state free precession MRI acquisition in children with single ventricles

Energy Technology Data Exchange (ETDEWEB)

Atweh, Lamya A.; Dodd, Nicholas A.; Krishnamurthy, Ramkumar; Chu, Zili D. [Texas Children' s Hospital, EB Singleton Department of Pediatric Radiology, Cardiovascular Imaging, Houston, TX (United States); Pednekar, Amol [Philips Healthcare, Houston, TX (United States); Krishnamurthy, Rajesh [Texas Children' s Hospital, EB Singleton Department of Pediatric Radiology, Cardiovascular Imaging, Houston, TX (United States); Baylor College of Medicine, Department of Radiology, Houston, TX (United States); Baylor College of Medicine, Department of Pediatrics, Houston, TX (United States)

2016-05-15

Breath-held two-dimensional balanced steady-state free precession cine acquisition (2-D breath-held SSFP), accelerated with parallel imaging, is the method of choice for evaluating ventricular function due to its superior blood-to-myocardial contrast, edge definition and high intrinsic signal-to-noise ratio throughout the cardiac cycle. The purpose of this study is to qualitatively and quantitatively compare the two different single-breath-hold 3-D cine SSFP acquisitions using 1) multidirectional sensitivity encoding (SENSE) acceleration factors (3-D multiple SENSE SSFP), and 2) k-t broad-use linear acceleration speed-up technique (3-D k-t SSFP) with the conventional 2-D breath-held SSFP in non-sedated asymptomatic volunteers and children with single ventricle congenital heart disease. Our prospective study was performed on 30 non-sedated subjects (9 healthy volunteers and 21 functional single ventricle patients), ages 12.5 +/- 2.8 years. Two-dimensional breath-held SSFP with SENSE acceleration factor of 2, eight-fold accelerated 3-D k-t SSFP, and 3-D multiple SENSE SSFP with total parallel imaging factor of 4 were performed to evaluate ventricular volumes and mass in the short-axis orientation. Image quality scores (blood myocardial contrast, edge definition and interslice alignment) and volumetric analysis (end systolic volume, end diastolic volume and ejection fraction) were performed on the data sets by experienced users. Paired t-test was performed to compare each of the 3-D k-t SSFP and 3-D multiple SENSE SSFP clinical scores against 2-D breath-held SSFP. Bland-Altman analysis was performed on left ventricle (LV) and single ventricle volumetry. Interobserver and intraobserver variability in volumetric measurements were determined using intraclass coefficients. The clinical scores were highest for the 2-D breath-held SSFP images. Between the two 3-D sequences, 3-D multiple SENSE SSFP performed better than 3-D k-t SSFP. Bland-Altman analysis for volumes

Breath hydrogen analysis in patients with ileoanal pouch anastomosis

DEFF Research Database (Denmark)

Bruun, E; Meyer, J N; Rumessen, J J

1995-01-01

The possible influence on functional outcomes of hydrogen production in the ileoanal pouch after restorative proctocolectomy was investigated by means of lactulose H2 breath tests. Eight of 15 patients had significant increases in breath hydrogen after 10 g lactulose. One patient declined...... to participate in further investigations, the remaining seven responders had no evidence of small bowel bacterial overgrowth after glucose H2 breath tests. The ability to produce hydrogen by anaerobic fermentation of lactulose in the pouch was unrelated to the age of the patients or of the pouch. Seven of eight...... responders had successive breath tests after ingestion of lactulose 20 g and wheat starch 100 g. Five of seven had significant increases after lactulose but none after wheat starch. The overall function of the pouch continence, spontaneity of defecation, and 24 hour stool frequency was significantly better...

A Pilot Study on the Effects of Slow Paced Breathing on Current Food Craving.

Science.gov (United States)

Meule, Adrian; Kübler, Andrea

2017-03-01

Heart rate variability biofeedback (HRV-BF) involves slow paced breathing (approximately six breaths per minute), thereby maximizing low-frequent heart rate oscillations and baroreflex gain. Mounting evidence suggests that HRV-BF promotes symptom reductions in a variety of physical and mental disorders. It may also positively affect eating behavior by reducing food cravings. The aim of the current study was to investigate if slow paced breathing can be useful for attenuating momentary food craving. Female students performed paced breathing either at six breaths per minute (n = 32) or at nine breaths per minute (n = 33) while watching their favorite food on the computer screen. Current food craving decreased during a first resting period, increased during paced breathing, and decreased during a second resting period in both conditions. Although current hunger increased in both conditions during paced breathing as well, it remained elevated after the second resting period in the nine breaths condition only. Thus, breathing rate did not influence specific food craving, but slow paced breathing appeared to have a delayed influence on state hunger. Future avenues are suggested for the study of HRV-BF in the context of eating behavior.

Natural Vibration of a Beam with a Breathing Oblique Crack

Directory of Open Access Journals (Sweden)

Yijiang Ma

2017-01-01

Full Text Available An analytical method is proposed to calculate the natural frequency of a cantilever beam with a breathing oblique crack. A double-linear-springs-model is developed in the modal analysis process to describe the breathing oblique crack, and the breathing behaviour of the oblique crack is objectively simulated. The finite element method (FEM analysis software ABAQUS is used to calculate the geometric correction factors when the cracked plate is subjected to a pure bending moment at different oblique crack angles and relative depths. The Galerkin method is applied to simplify the cracked beam to a single degree of freedom system, allowing the natural frequency of the beam with the breathing oblique crack to be calculated. Compared with the natural frequencies of the breathing oblique cracked beam obtained using the ABAQUS FEM method, the proposed analytical method exhibits a high computational accuracy, with a maximum error of only 4.65%.

Forced Air-Breathing PEMFC Stacks

Directory of Open Access Journals (Sweden)

K. S. Dhathathreyan

2012-01-01

Full Text Available Air-breathing fuel cells have a great potential as power sources for various electronic devices. They differ from conventional fuel cells in which the cells take up oxygen from ambient air by active or passive methods. The air flow occurs through the channels due to concentration and temperature gradient between the cell and the ambient conditions. However developing a stack is very difficult as the individual cell performance may not be uniform. In order to make such a system more realistic, an open-cathode forced air-breathing stacks were developed by making appropriate channel dimensions for the air flow for uniform performance in a stack. At CFCT-ARCI (Centre for Fuel Cell Technology-ARC International we have developed forced air-breathing fuel cell stacks with varying capacity ranging from 50 watts to 1500 watts. The performance of the stack was analysed based on the air flow, humidity, stability, and so forth, The major advantage of the system is the reduced number of bipolar plates and thereby reduction in volume and weight. However, the thermal management is a challenge due to the non-availability of sufficient air flow to remove the heat from the system during continuous operation. These results will be discussed in this paper.

Theme and variations: amphibious air-breathing intertidal fishes.

Science.gov (United States)

Martin, K L

2014-03-01

Over 70 species of intertidal fishes from 12 families breathe air while emerging from water. Amphibious intertidal fishes generally have no specialized air-breathing organ but rely on vascularized mucosae and cutaneous surfaces in air to exchange both oxygen and carbon dioxide. They differ from air-breathing freshwater fishes in morphology, physiology, ecology and behaviour. Air breathing and terrestrial activity are present to varying degrees in intertidal fish species, correlated with the tidal height of their habitat. The gradient of amphibious lifestyle includes passive remainers that stay in the intertidal zone as tides ebb, active emergers that deliberately leave water in response to poor aquatic conditions and highly mobile amphibious skipper fishes that may spend more time out of water than in it. Normal terrestrial activity is usually aerobic and metabolic rates in air and water are similar. Anaerobic metabolism may be employed during forced exercise or when exposed to aquatic hypoxia. Adaptations for amphibious life include reductions in gill surface area, increased reliance on the skin for respiration and ion exchange, high affinity of haemoglobin for oxygen and adjustments to ventilation and metabolism while in air. Intertidal fishes remain close to water and do not travel far terrestrially, and are unlikely to migrate or colonize new habitats at present, although in the past this may have happened. Many fish species spawn in the intertidal zone, including some that do not breathe air, as eggs and embryos that develop in the intertidal zone benefit from tidal air emergence. With air breathing, amphibious intertidal fishes survive in a variable habitat with minimal adjustments to existing structures. Closely related species in different microhabitats provide unique opportunities for comparative studies. © 2013 The Fisheries Society of the British Isles.

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: NEW CONDENSATOR, INC.--THE CONDENSATOR DIESEL ENGINE RETROFIT CRANKCASE VENTILATION SYSTEM

Science.gov (United States)

EPA's Environmental Technology Verification Program has tested New Condensator Inc.'s Condensator Diesel Engine Retrofit Crankcase Ventilation System. Brake specific fuel consumption (BSFC), the ratio of engine fuel consumption to the engine power output, was evaluated for engine...

Breathing Air Purification for Hyperbaric Purposes, Part II

Directory of Open Access Journals (Sweden)

Woźniak Arkadiusz

2015-03-01

Full Text Available Determining the efficiency of breathing air purification for hyperbaric purposes with the use of filtration systems is of a crucial importance. However, when the Polish Navy took samples of breathing air from their own filtration plant for quality purposes, these were found to not meet the required standard. The identification of this problem imposed the need to undertake actions aimed at the elimination of the identified disruptions in the process of breathing air production, with the objective of assuring its proper quality. This study presents the results of the initial tests on the air supply sources utilised by the Polish Navy, which were carried out for the purpose of setting a proper direction of future works and implementing corrective measures in order to optimise the breathing air production process. The obtained test results will be used in a subsequent publication devoted to the assessment of the level of efficiency of air purification with the use of a multifaceted approach consisting in the utilisation of various types of air supply sources and different configurations of purification systems.

BREATHING EXERCISE RELAXATION INCREASE PHSYCOLOGICAL RESPONSE PRESCHOOL CHILDREN

Directory of Open Access Journals (Sweden)

Yuni Sufyanti Arief

2017-07-01

Full Text Available Introduction: Being hospitalize will be made the children become stress. Hospitalization response of the child particularly is afraid sense regard to painfull procedure and increase to attack the invasive procedure. The aimed of this study was to describe the influence of breathing exercise relaxation technique regarded to phsycological receiving responses in the preeliminary school chidren while they were receiving invasive procedure. Method: A quasy experimental purposive sampling design was used in this study. There were 20 respondents who met to the inclusion criteria. The independent variable was the breathing exercise relaxation technique and the dependent variable was phsycological receiving responses. Data for phsylogical response were collected by using observation form then analyzed by using Wilcoxon Signed Rank Test and Mann Whitney U Test with significance level α≤0.05. Result :  The result showed that breathing exercise relaxation technique had significance influence to phsycological response (p=0.000. Discussion: It,s can be concluded that breathing exercise relaxation technique has an effect to increase pshycological response in preeliminary school children who received invasive procedure.

SU-F-T-415: Differences in Lung Sparing in Deep Inspiration Breath-Hold and Free Breathing Breast Plans Calculated in Pinnacle and Monaco

Energy Technology Data Exchange (ETDEWEB)

Saenz, D; Stathakis, S [University of Texas Health Science Center San Antonio, San Antonio, TX (United States)

2016-06-15

Purpose: Deep inspiration breath-hold (DIBH) is used for left-sided breast radiotherapy to spare the heart and lung. The magnitude of sparing has been shown to be significant. Monte Carlo, furthermore, has the potential to calculate most accurately the dose in the heterogeneous lung medium at the interface with the lung wall. The lung dose was investigated in Monaco to determine the level of sparing relative to that calculated in Pinnacle{sup 3}. Methods: Five patients undergoing DIBH radiotherapy on an Elekta Versa HD linear accelerator in conjunction with the Catalyst C-RAD surface imaging system were planned using Phillips Pinnacle{sup 3}. Free breathing plans were also created to clinically assure a benefit. Both plans were re-calculated in Monaco to determine if there were any significant differences. The mean heart dose, mean left lung, and mean total lung dose were compared in addition to the V20 for left and both lungs. Dose was calculated as dose to medium as well as dose to water with a statistical precision of 0.7%. Results: Mean lung dose was significantly different (p < 0.003) between the two calculations for both DIBH (11.6% higher in Monaco) and free breathing (14.2% higher in Monaco). V20 was also higher in Monaco (p < 0.05) for DIBH (5.7% higher) and free breathing (4.9% higher). The mean heart dose was not significantly different between the dose calculations for either DIBH or free breathing. Results were no more than 0.1% different when calculated as dose to water. Conclusion: The use of Monte Carlo can provide insight on the lung dose for both free breathing and DIBH techniques for whole breast irradiation. While the sparing (dose reductions with DIBH as compared to free breathing) is equivalent for either planning system, the lung doses themselves are higher when calculated with Monaco.

Quality factors to consider in condensate selection

Energy Technology Data Exchange (ETDEWEB)

Lywood, B. [Crude Quality Inc., Edmonton, AB (Canada)

2009-07-01

Many factors must be considered when assessing the feasibility of using condensates as a diluent for bitumen or heavy crude production blending. In addition to commercial issues, the effect of condensate quality is a key consideration. In general, condensate quality refers to density and viscosity. However, valuation decisions could be enhanced through the expansion of quality definitions and understanding. This presentation focused on the parameters that are important in choosing a diluent grade product. It also reviewed pipeline and industry specifications and provided additional information regarding general properties for bitumen and condensate compatibility; sampling and quality testing needs; and existing sources of information regarding condensate quality. tabs., figs.

Air-Breathing Launch Vehicle Technology Being Developed

Science.gov (United States)

Trefny, Charles J.

2003-01-01

Of the technical factors that would contribute to lowering the cost of space access, reusability has high potential. The primary objective of the GTX program is to determine whether or not air-breathing propulsion can enable reusable single-stage-to-orbit (SSTO) operations. The approach is based on maturation of a reference vehicle design with focus on the integration and flight-weight construction of its air-breathing rocket-based combined-cycle (RBCC) propulsion system.

Advances in modelling of condensation phenomena

Energy Technology Data Exchange (ETDEWEB)

Liu, W.S.; Zaltsgendler, E. [Ontario Hydro Nuclear, Toronto (Canada); Hanna, B. [Atomic Energy of Canada Limited, Pinawa, Manitoba (Canada)

1997-07-01

The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described.

Advances in modelling of condensation phenomena

International Nuclear Information System (INIS)

Liu, W.S.; Zaltsgendler, E.; Hanna, B.

1997-01-01

The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described

Condensation on Superhydrophobic Copper Oxide Nanostructures

OpenAIRE

Enright, Ryan; Miljkovic, Nenad; Dou, Nicholas; Nam, Youngsuk; Wang, Evelyn N.

2013-01-01

Condensation is an important process in both emerging and traditional power generation and water desalination technologies. Superhydrophobic nanostructures promise enhanced condensation heat transfer by reducing the characteristic size of departing droplets via a surface-tension-driven mechanism [1]. In this work, we investigated a scalable synthesis technique to produce oxide nanostructures on copper surfaces capable of sustaining superhydrophobic condensation and characterized the growth an...

Defences against ammonia toxicity in tropical air-breathing fishes exposed to high concentrations of environmental ammonia: a review.

Science.gov (United States)

Ip, Y K; Chew, S F; Wilson, J M; Randall, D J

2004-10-01

In the tropics, air-breathing fishes can be exposed to environmental ammonia when stranded in puddles of water during the dry season, during a stay inside a burrow, or after agricultural fertilization. At low concentrations of environmental ammonia, NH(3) excretion is impeded, as in aerial exposure, leading to the accumulation of endogenous ammonia. At high concentrations of environmental ammonia, which results in a reversed NH(3) partial pressure gradient (DeltaP(NH3)), there is retention of endogenous ammonia and uptake of exogenous ammonia. In this review, several tropical air-breathing fishes (giant mudskipper, African catfish, oriental weatherloach, swamp eel, four-eyed sleeper, abehaze and slender African lungfish), which can tolerate high environmental ammonia exposure, are used as examples to demonstrate how eight different adaptations can be involved in defence against ammonia toxicity. Four of these adaptations deal with ammonia toxicity at branchial and/or epithelial surfaces: (1) active excretion of NH(4)(+); (2) lowering of environmental pH; (3) low NH(3) permeability of epithelial surfaces; and (4) volatilization of NH(3), while another four adaptations ameliorate ammonia toxicity at the cellular and subcellular levels: (5) high tolerance of ammonia at the cellular and subcellular levels; (6) reduction in ammonia production; (7) glutamine synthesis; and (8) urea synthesis. The responses of tropical air-breathing fishes to high environmental ammonia are determined apparently by behavioural adaptations and the nature of their natural environments.

Condensation heat transfer coefficient of air-cooled condensing heat exchanger of emergency cooldown tank in long-term passive cooling system

International Nuclear Information System (INIS)

Huh, Seon Jeong; Lee, Hee Joon; Moon, Joo Hyung; Bae, Youngmin; Kim, Young In

2017-01-01

For the design purpose of air-cooled condensing heat exchanger of emergency cooldown tank, average condensation heat transfer coefficient inside a circular tube was reduced by a thermal sizing program using the experimental data of Kim et al. It was compared to the existing condensation heat transfer correlations. Moreover, a sensitivity analysis of both inside condensation and outside air natural convection correlations was performed. Although condensation heat transfer did not play a great role to design over 10 3 W/m 2 /K, the improved Shah's correlation gives the best prediction for the design. Consequently, air natural convection coefficient significantly affects the design of air-cooled condensing heat exchanger. (author)

Molecular equilibrium with condensation

International Nuclear Information System (INIS)

Sharp, C.M.; Huebner, W.F.

1990-01-01

Minimization of the Gibbs energy of formation for species of chemical elements and compounds in their gas and condensed phases determines their relative abundances in a mixture in chemical equilibrium. The procedure is more general and more powerful than previous abundance determinations in multiphase astrophysical mixtures. Some results for astrophysical equations of state are presented, and the effects of condensation on opacity are briefly indicated. 18 refs

Continuous condensation in nanogrooves

Science.gov (United States)

Malijevský, Alexandr

2018-05-01

We consider condensation in a capillary groove of width L and depth D , formed by walls that are completely wet (contact angle θ =0 ), which is in a contact with a gas reservoir of the chemical potential μ . On a mesoscopic level, the condensation process can be described in terms of the midpoint height ℓ of a meniscus formed at the liquid-gas interface. For macroscopically deep grooves (D →∞ ), and in the presence of long-range (dispersion) forces, the condensation corresponds to a second-order phase transition, such that ℓ ˜(μcc-μ ) -1 /4 as μ →μcc - where μc c is the chemical potential pertinent to capillary condensation in a slit pore of width L . For finite values of D , the transition becomes rounded and the groove becomes filled with liquid at a chemical potential higher than μc c with a difference of the order of D-3. For sufficiently deep grooves, the meniscus growth initially follows the power law ℓ ˜(μcc-μ ) -1 /4 , but this behavior eventually crosses over to ℓ ˜D -(μ-μc c) -1 /3 above μc c, with a gap between the two regimes shown to be δ ¯μ ˜D-3 . Right at μ =μc c , when the groove is only partially filled with liquid, the height of the meniscus scales as ℓ*˜(D3L) 1 /4 . Moreover, the chemical potential (or pressure) at which the groove is half-filled with liquid exhibits a nonmonotonic dependence on D with a maximum at D ≈3 L /2 and coincides with μc c when L ≈D . Finally, we show that condensation in finite grooves can be mapped on the condensation in capillary slits formed by two asymmetric (competing) walls a distance D apart with potential strengths depending on L . All these predictions, based on mesoscopic arguments, are confirmed by fully microscopic Rosenfeld's density functional theory with a reasonable agreement down to surprisingly small values of both L and D .

Combined sensing platform for advanced diagnostics in exhaled mouse breath

Science.gov (United States)

Fortes, Paula R.; Wilk, Andreas; Seichter, Felicia; Cajlakovic, Merima; Koestler, Stefan; Ribitsch, Volker; Wachter, Ulrich; Vogt, Josef; Radermacher, Peter; Carter, Chance; Raimundo, Ivo M.; Mizaikoff, Boris

2013-03-01

Breath analysis is an attractive non-invasive strategy for early disease recognition or diagnosis, and for therapeutic progression monitoring, as quantitative compositional analysis of breath can be related to biomarker panels provided by a specific physiological condition invoked by e.g., pulmonary diseases, lung cancer, breast cancer, and others. As exhaled breath contains comprehensive information on e.g., the metabolic state, and since in particular volatile organic constituents (VOCs) in exhaled breath may be indicative of certain disease states, analytical techniques for advanced breath diagnostics should be capable of sufficient molecular discrimination and quantification of constituents at ppm-ppb - or even lower - concentration levels. While individual analytical techniques such as e.g., mid-infrared spectroscopy may provide access to a range of relevant molecules, some IR-inactive constituents require the combination of IR sensing schemes with orthogonal analytical tools for extended molecular coverage. Combining mid-infrared hollow waveguides (HWGs) with luminescence sensors (LS) appears particularly attractive, as these complementary analytical techniques allow to simultaneously analyze total CO2 (via luminescence), the 12CO2/13CO2 tracer-to-tracee (TTR) ratio (via IR), selected VOCs (via IR) and O2 (via luminescence) in exhaled breath, yet, establishing a single diagnostic platform as both sensors simultaneously interact with the same breath sample volume. In the present study, we take advantage of a particularly compact (shoebox-size) FTIR spectrometer combined with novel substrate-integrated hollow waveguide (iHWG) recently developed by our research team, and miniaturized fiberoptic luminescence sensors for establishing a multi-constituent breath analysis tool that is ideally compatible with mouse intensive care stations (MICU). Given the low tidal volume and flow of exhaled mouse breath, the TTR is usually determined after sample collection via gas

Direct contact condensation in packed beds

Energy Technology Data Exchange (ETDEWEB)

Li, Yi; Klausner, James F.; Mei, Renwei; Knight, Jessica [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611 (United States)

2006-12-15

A diffusion driven desalination process was recently described where a very effective direct contact condenser with a packed bed is used to condense water vapor out of an air/vapor mixture. A laboratory scale direct contact condenser has been fabricated as a twin tower structure with two stages, co-current and countercurrent. Experiments have been operated in each stage with respective saturated air inlet temperatures of 36, 40 and 43{sup o}C. The temperature and humidity data have been collected at the inlet and exit of the packed bed for different water to air mass flow ratios that vary between 0 and 2.5. A one-dimensional model based on conservation principles has been developed, which predicts the variation of temperature, humidity, and condensation rate through the condenser stages. Agreement between the model and experiments is very good. It is observed that the countercurrent flow stage condensation effectiveness is significantly higher than that for the co-current stage. The condensation heat and mass transfer rates were found to decrease when water blockages occur within the packed bed. Using high-speed digital cinematography, it was observed that this problem can occur at any operating condition, and is dependent on the packing surface wetting characteristics. This observation is used to explain the requirement for two different empirical constants, depending on packing diameter, suggested by Onda for the air side mass transfer coefficient correlation. (author)

14C-urea breath test for the detection of Helicobacter pylori

NARCIS (Netherlands)

Veldhuyzen van Zanten, S. J.; Tytgat, K. M.; Hollingsworth, J.; Jalali, S.; Rshid, F. A.; Bowen, B. M.; Goldie, J.; Goodacre, R. L.; Riddell, R. H.; Hunt, R. H.

1990-01-01

The high urease activity of Helicobacter pylori can be used to detect this bacterium by noninvasive breath tests. We have developed a 14C-urea breath test which uses 5 microCi 14C with 50 mg nonradioactive urea. Breath samples are collected at baseline and every 30 min for 2 h. Our study compared

Alkalization of steam and condensate with 2-amino-1-butanol and hydrazine; Alkalisering av aanga och kondensat med butanolamin och hydrazin

Energy Technology Data Exchange (ETDEWEB)

Falk, I [Studsvik Material AB, Nykoeping (Sweden)

1996-04-01

To maintain a low corrosion level in steam- and condensate systems at power and industrial plants, an alkalization of the steam is needed. A low corrosion level lowers the risk of operation disturbances and reduces the cost of the condensate clean up. A better knowledge in the behavior of the alkalis will improve the possibilities to avoid the corrosion attacks. In this work experimental measurements have been carried out during steam boiler conditions as temperature, continuous steam generation and condensation. It has been found that the volatility of 2-amino-1-butanol is very low during stationary dynamic conditions at 250 deg C and 120 deg C. To achieve a high ph-value in the final condensate a very high concentration of 2-amino-1-butanol is thus needed especially when the steam contains acidic compounds. The alkalization effect is obtained from ammonia which is created by thermal decomposition of hydrazine in the boiler water. It is necessary to carry out experimental investigations showing the thermal stability of organic compounds in boiler water before it is possible to recommend them as better volatile alkalis than ammonia and hydrazine. 6 refs, 13 figs

Organic condensation: a vital link connecting aerosol formation to cloud condensation nuclei (CCN) concentrations

Science.gov (United States)

Riipinen, I.; Pierce, J. R.; Yli-Juuti, T.; Nieminen, T.; Häkkinen, S.; Ehn, M.; Junninen, H.; Lehtipalo, K.; Petäjä, T.; Slowik, J.; Chang, R.; Shantz, N. C.; Abbatt, J.; Leaitch, W. R.; Kerminen, V.-M.; Worsnop, D. R.; Pandis, S. N.; Donahue, N. M.; Kulmala, M.

2011-04-01

Atmospheric aerosol particles influence global climate as well as impair air quality through their effects on atmospheric visibility and human health. Ultrafine (<100 nm) particles often dominate aerosol numbers, and nucleation of atmospheric vapors is an important source of these particles. To have climatic relevance, however, the freshly nucleated particles need to grow in size. We combine observations from two continental sites (Egbert, Canada and Hyytiälä, Finland) to show that condensation of organic vapors is a crucial factor governing the lifetimes and climatic importance of the smallest atmospheric particles. We model the observed ultrafine aerosol growth with a simplified scheme approximating the condensing species as a mixture of effectively non-volatile and semi-volatile species, demonstrate that state-of-the-art organic gas-particle partitioning models fail to reproduce the observations, and propose a modeling approach that is consistent with the measurements. We find that roughly half of the mass of the condensing mass needs to be distributed proportional to the aerosol surface area (thus implying that the condensation is governed by gas-phase concentration rather than the equilibrium vapour pressure) to explain the observed aerosol growth. We demonstrate the large sensitivity of predicted number concentrations of cloud condensation nuclei (CCN) to these interactions between organic vapors and the smallest atmospheric nanoparticles - highlighting the need for representing this process in global climate models.

Scrutinizing the pion condensed phase

Energy Technology Data Exchange (ETDEWEB)

Carignano, Stefano; Mammarella, Andrea; Mannarelli, Massimo [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Lepori, Luca [Universita di Padova, Dipartimento di Fisica e Astronomia, Padova (Italy); Universita dell' Aquila, Dipartimento di Scienze Fisiche e Chimiche, Coppito-L' Aquila (Italy); Pagliaroli, Giulia [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Gran Sasso Science Institute, L' Aquila (Italy)

2017-02-15

When the isospin chemical potential exceeds the pion mass, charged pions condense in the zero-momentum state forming a superfluid. Chiral perturbation theory provides a very powerful tool for studying this phase. However, the formalism that is usually employed in this context does not clarify various aspects of the condensation mechanism and makes the identification of the soft modes problematic. We re-examine the pion condensed phase using different approaches within the chiral perturbation theory framework. As a first step, we perform a low-density expansion of the chiral Lagrangian valid close to the onset of the Bose-Einstein condensation. We obtain an effective theory that can be mapped to a Gross-Pitaevskii Lagrangian in which, remarkably, all the coefficients depend on the isospin chemical potential. The low-density expansion becomes unreliable deep in the pion condensed phase. For this reason, we develop an alternative field expansion deriving a low-energy Lagrangian analog to that of quantum magnets. By integrating out the ''radial'' fluctuations we obtain a soft Lagrangian in terms of the Nambu-Goldstone bosons arising from the breaking of the pion number symmetry. Finally, we test the robustness of the second-order transition between the normal and the pion condensed phase when next-to-leading-order chiral corrections are included. We determine the range of parameters for turning the second-order phase transition into a first-order one, finding that the currently accepted values of these corrections are unlikely to change the order of the phase transition. (orig.)

Effect of influenza vaccination on oxidative stress products in breath.

Science.gov (United States)

Phillips, Michael; Cataneo, Renee N; Chaturvedi, Anirudh; Danaher, Patrick J; Devadiga, Anantrai; Legendre, David A; Nail, Kim L; Schmitt, Peter; Wai, James

2010-06-01

Viral infections cause increased oxidative stress, so a breath test for oxidative stress biomarkers (alkanes and alkane derivatives) might provide a new tool for early diagnosis. We studied 33 normal healthy human subjects receiving scheduled treatment with live attenuated influenza vaccine (LAIV). Each subject was his or her own control, since they were studied on day 0 prior to vaccination, and then on days 2, 7 and 14 following vaccination. Breath volatile organic compounds (VOCs) were collected with a breath collection apparatus, then analyzed by automated thermal desorption with gas chromatography and mass spectroscopy. A Monte Carlo simulation technique identified non-random VOC biomarkers of infection based on their C-statistic values (area under curve of receiver operating characteristic). Treatment with LAIV was followed by non-random changes in the abundance of breath VOCs. 2, 8-Dimethyl-undecane and other alkane derivatives were observed on all days. Conservative multivariate models identified vaccinated subjects on day 2 (C-statistic = 0.82, sensitivity = 63.6% and specificity = 88.5%); day 7 (C-statistic = 0.94, sensitivity = 88.5% and specificity = 92.3%); and day 14 (C-statistic = 0.95, sensitivity = 92.3% and specificity = 92.3%). The altered breath VOCs were not detected in live attenuated influenza vaccine, excluding artifactual contamination. LAIV vaccination in healthy humans elicited a prompt and sustained increase in breath biomarkers of oxidative stress. A breath test for these VOCs could potentially identify humans who are acutely infected with influenza, but who have not yet developed clinical symptoms or signs of disease.

Breath tests and irritable bowel syndrome.

Science.gov (United States)

Rana, Satya Vati; Malik, Aastha

2014-06-28

Breath tests are non-invasive tests and can detect H₂ and CH₄ gases which are produced by bacterial fermentation of unabsorbed intestinal carbohydrate and are excreted in the breath. These tests are used in the diagnosis of carbohydrate malabsorption, small intestinal bacterial overgrowth, and for measuring the orocecal transit time. Malabsorption of carbohydrates is a key trigger of irritable bowel syndrome (IBS)-type symptoms such as diarrhea and/or constipation, bloating, excess flatulence, headaches and lack of energy. Abdominal bloating is a common nonspecific symptom which can negatively impact quality of life. It may reflect dietary imbalance, such as excess fiber intake, or may be a manifestation of IBS. However, bloating may also represent small intestinal bacterial overgrowth. Patients with persistent symptoms of abdominal bloating and distension despite dietary interventions should be referred for H₂ breath testing to determine the presence or absence of bacterial overgrowth. If bacterial overgrowth is identified, patients are typically treated with antibiotics. Evaluation of IBS generally includes testing of other disorders that cause similar symptoms. Carbohydrate malabsorption (lactose, fructose, sorbitol) can cause abdominal fullness, bloating, nausea, abdominal pain, flatulence, and diarrhea, which are similar to the symptoms of IBS. However, it is unclear if these digestive disorders contribute to or cause the symptoms of IBS. Research studies show that a proper diagnosis and effective dietary intervention significantly reduces the severity and frequency of gastrointestinal symptoms in IBS. Thus, diagnosis of malabsorption of these carbohydrates in IBS using a breath test is very important to guide the clinician in the proper treatment of IBS patients.

Demonstration of Nautilus Centripetal Capillary Condenser Technology

Science.gov (United States)

Wheeler, RIchard; Tang, Linh; Wambolt, Spencer; Golliher, Eric; Agui, Juan

2016-01-01

This paper describes the results of a proof of concept effort for development of a Nautilus Centripetal Capillary Condenser (NCCC or NC3) used for microgravity compatible water recovery from moist air with integral passive phase separation. Removal of liquid condensate from the air stream exiting a condenser is readily performed here on Earth. In order to perform this function in space however, without gravity or mechanical action, other tactics including utilization of inertial, drag and capillary forces are required. Within the NC3, liquid water forms via condensation on cold condenser surfaces as humid air passes along multiple spiral channels, each in its own plane, all together forming a stacked plate assembly. Non-mechanical inertial forces are employed to transfer condensate, as it forms, via centripetal action to the outer perimeter of each channel. A V-shaped groove, constructed on this outer edge of the spiral channel, increases local capillary forces thereby retaining the liquid. Air drag then pulls the liquid along to a collection region near the center of the device. Dry air produced by each parallel spiral channel is combined in a common orthogonal, out-of-plane conduit passing down the axial center of the stacked device. Similarly, the parallel condensate streams are combined and removed from the condenser/separator through yet another out-of-plane axial conduit. NC3 is an integration of conventional finned condenser operation, combined with static phase separation and capillary transport phenomena. A Mars' transit mission would be a logical application for this technology where gravity is absent and the use of vibrating, energy-intensive, motor-driven centrifugal separators is undesired. Here a vapor stream from either the Heat Melt Compactor or the Carbon dioxide Reduction Assembly, for example, would be dried to a dew point of 10 deg using a passive NC3 condenser/separator with the precious water condensate recycled to the water bus.

Bose-Einstein condensation of light: general theory.

Science.gov (United States)

Sob'yanin, Denis Nikolaevich

2013-08-01

A theory of Bose-Einstein condensation of light in a dye-filled optical microcavity is presented. The theory is based on the hierarchical maximum entropy principle and allows one to investigate the fluctuating behavior of the photon gas in the microcavity for all numbers of photons, dye molecules, and excitations at all temperatures, including the whole critical region. The master equation describing the interaction between photons and dye molecules in the microcavity is derived and the equivalence between the hierarchical maximum entropy principle and the master equation approach is shown. The cases of a fixed mean total photon number and a fixed total excitation number are considered, and a much sharper, nonparabolic onset of a macroscopic Bose-Einstein condensation of light in the latter case is demonstrated. The theory does not use the grand canonical approximation, takes into account the photon polarization degeneracy, and exactly describes the microscopic, mesoscopic, and macroscopic Bose-Einstein condensation of light. Under certain conditions, it predicts sub-Poissonian statistics of the photon condensate and the polarized photon condensate, and a universal relation takes place between the degrees of second-order coherence for these condensates. In the macroscopic case, there appear a sharp jump in the degrees of second-order coherence, a sharp jump and kink in the reduced standard deviations of the fluctuating numbers of photons in the polarized and whole condensates, and a sharp peak, a cusp, of the Mandel parameter for the whole condensate in the critical region. The possibility of nonclassical light generation in the microcavity with the photon Bose-Einstein condensate is predicted.

Condensation Enhancement by Surface Porosity: Three-Stage Mechanism.

Science.gov (United States)

Yarom, Michal; Marmur, Abraham

2015-08-18

Surface defects, such as pores, cracks, and scratches, are naturally occurring and commonly found on solid surfaces. However, the mechanism by which such imperfections promote condensation has not been fully explored. In the current paper we thermodynamically analyze the ability of surface porosity to enhance condensation on a hydrophilic solid. We show that the presence of a surface-embedded pore brings about three distinct stages of condensation. The first is capillary condensation inside the pore until it is full. This provides an ideal hydrophilic surface for continuing the condensation. As a result, spontaneous condensation and wetting can be achieved at lower vapor pressure than on a smooth surface.

Medication effects on sleep and breathing.

Science.gov (United States)

Seda, Gilbert; Tsai, Sheila; Lee-Chiong, Teofilo

2014-09-01

Sleep respiration is regulated by circadian, endocrine, mechanical and chemical factors, and characterized by diminished ventilatory drive and changes in Pao2 and Paco2 thresholds. Hypoxemia and hypercapnia are more pronounced during rapid eye movement. Breathing is influenced by sleep stage and airway muscle tone. Patient factors include medical comorbidities and body habitus. Medications partially improve obstructive sleep apnea and stabilize periodic breathing at altitude. Potential adverse consequences of medications include precipitation or worsening of disorders. Risk factors for adverse medication effects include aging, medical disorders, and use of multiple medications that affect respiration. Published by Elsevier Inc.

CO2 capture by Condensed Rotational Separation

NARCIS (Netherlands)

Benthum, van R.J.; Kemenade, van H.P.; Brouwers, J.J.H.; Golombok, M.

2010-01-01

Condensed Rotational Separation (CRS) technology is a patented method to upgrade gas mixtures. A novel application is thecapture of CO2 from coal-combustion fired power stations: Condensed Contaminant Centrifugal Separation in Coal Combustion(C5sep). CRS involves partial condensation of a gas

The effects of metronome breathing on the variability of autonomic activity measurements.

Science.gov (United States)

Driscoll, D; Dicicco, G

2000-01-01

Many chiropractors hypothesize that spinal manipulation affects the autonomic nervous system (ANS). However, the ANS responses to chiropractic manipulative therapy are not well documented, and more research is needed to support this hypothesis. This study represents a step toward the development of a reliable method by which to document that chiropractic manipulative therapy does affect the ANS by exploring the use of paced breathing as a way to reduce the inherent variability in ANS measurements. To examine the hypothesis that the variability of ANS measurements would be reduced if breathing were paced to a metronome at 12 breaths/min. The study was performed at Parker College Research Institute. Eight normotensive subjects were recruited from the student body and staff. Respiration frequency was measured through a strain gauge. A 3-lead electrocardiogram (ECG) was used to register the electric activity of the heart, and arterial tonometry monitors were used to record the left and right radial artery blood pressures. Signals were recorded on an IBM-compatible computer with a sampling frequency of 100 Hz. Normal breathing was used for the first 3 recordings, and breathing was paced to a metronome for the final 3 recordings at 12 breaths/min. Fourier analysis was performed on the beat-by-beat fluctuations of the ECG-determined R-R interval and systolic arterial pressure (SBP). Low-frequency fluctuations (LF; 0.04-0.15 Hz) reflected sympathetic activity, whereas high-frequency fluctuations (HF; 0.15-0.4 Hz) represented parasympathetic activity. Sympathovagal indices were determined from the ratio of the two bandwidths (LF/HF). The coefficient of variation (CV%) for autonomic parameters was calculated ([average/SD] x 100%) to compare breathing normally and breathing to a metronome with respect to variability. One-way analysis of variance was used to detect differences. A value of P Metronome breathing did not produce any significant changes in blood pressure for the

Vortex sorter for Bose-Einstein condensates

International Nuclear Information System (INIS)

Whyte, Graeme; Veitch, John; Courtial, Johannes; Oehberg, Patrik

2004-01-01

We have designed interferometers that sort Bose-Einstein condensates into their vortex components. The Bose-Einstein condensates in the two arms of the interferometer are rotated with respect to each other through fixed angles; different vortex components then exit the interferometer in different directions. The method we use to rotate the Bose-Einstein condensates involves asymmetric phase imprinting and is itself new. We have modeled rotation through fixed angles and sorting into vortex components with even and odd values of the topological charge of two-dimensional Bose-Einstein condensates in a number of states (pure or superposition vortex states for different values of the scattering length). Our scheme may have applications for quantum information processing

Condensate treatment and oxygen control in power plants

International Nuclear Information System (INIS)

Sakai, Toshiaki; Iida, Kei; Ohashi, Shinichi.

1997-01-01

In thermal and nuclear power stations, the steam that operated turbines is cooled and condensed with condensers. The condensate is heated again with boilers, nuclear reactors or steam generators, but if corrosion products or impurities are contained in the condensate, corrosion and scale formation occur in boilers and others. The filtration facility and the desalting facility for condensate are installed to remove impurities, but water quality control is different in thermal, BWR and PWR plants, therefore, the treatment facilities corresponding to respective condensates have been adopted. In order to reduce the amount of clud generation, the treatment of injecting a small quantity of oxygen into condensate has been adopted. In thermal power plants, all volatile treatment is carried out, in which corrosion is prevented by the addition of ammonia and hydrazine to boiler feedwater. The condensate filters of various types and the NH 4 type condensate desalter for thermal power plants are described. In BWR power plants, steam is generated in nuclear reactors, therefore, the addition of chemicals into water is never carried out, and high purity neutral water is used. In PWR power plants, the addition of chemicals to water is done in the primary system, and AVT is adopted in the secondary system. Also the condensate treatment facilities are different for both reactors. (K.I.)

Boilers, evaporators, and condensers

International Nuclear Information System (INIS)

Kakac, S.

1991-01-01

This book reports on the boilers, evaporators and condensers that are used in power plants including nuclear power plants. Topics included are forced convection for single-phase side heat exchangers, heat exchanger fouling, industrial heat exchanger design, fossil-fuel-fired boilers, once through boilers, thermodynamic designs of fossil fuel-first boilers, evaporators and condensers in refrigeration and air conditioning systems (with respect to reducing CFC's) and nuclear steam generators

Symptoms of Sleep Disordered Breathing and Risk of Cancer

DEFF Research Database (Denmark)

Christensen, Anne Sofie; Clark, Alice; Salo, Paula

2013-01-01

Sleep disordered breathing (SDB) has been associated with oxidative stress, inflammation, and altered hormonal levels, all of which could affect the risk of cancer. The aim of the study is to examine if symptoms of SDB including snoring, breathing cessations, and daytime sleepiness affect...

Condensed matter physics in electrochemistry

International Nuclear Information System (INIS)

Kornyshev, A.A.

1991-01-01

Some topics in electrochemistry are considered from the condensed matter physics viewpoint in relation to the problems discussed in this book. Examples of the successful application of condensed matter physics to electrochemistry are discussed together with prospective problems and pressing questions. (author). 127 refs, 4 figs

Ventilatory and Cardiovascular Regulation in the Air-Breathing Fish Pangasianodon Hypophthalmus

DEFF Research Database (Denmark)

Thomsen, Mikkel; Wang, Tobias; Bayley, Mark

The air-breathing fish Pangasianodon hypophthalmus is abundant in the Mekong river system where it is also intensively cultured. In contrast to most other air-breathing fishes it has well developed gills as well as a highly traberculated swim bladder with a large surface area used for air-breathing...... systems provide information on when gill ventilation is insufficient for oxygen uptake and hence initiate air-breathing. Here we investigate the ventilatory and cardiovascular responses to changes in either in the external media or internally in the blood in resting fish. We found ventilation in P....... Its native waters have been shown to be periodically strongly hypoxic and hypercarbic, forcing P. hypophthalmus to switch from exclusively branchial ventilation to air-breathing to maintain its aerobic metabolism. This ability to switch respiratory media demands that the oxygen- and CO¬2 sensory...

Competition between Bose-Einstein Condensation and Spin Dynamics.

Science.gov (United States)

Naylor, B; Brewczyk, M; Gajda, M; Gorceix, O; Maréchal, E; Vernac, L; Laburthe-Tolra, B

2016-10-28

We study the impact of spin-exchange collisions on the dynamics of Bose-Einstein condensation by rapidly cooling a chromium multicomponent Bose gas. Despite relatively strong spin-dependent interactions, the critical temperature for Bose-Einstein condensation is reached before the spin degrees of freedom fully thermalize. The increase in density due to Bose-Einstein condensation then triggers spin dynamics, hampering the formation of condensates in spin-excited states. Small metastable spinor condensates are, nevertheless, produced, and they manifest in strong spin fluctuations.

21 CFR 886.1380 - Diagnostic condensing lens.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic condensing lens. 886.1380 Section 886...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1380 Diagnostic condensing lens. (a) Identification. A diagnostic condensing lens is a device used in binocular indirect ophthalmoscopy (a procedure...

The dynamics of Affleck-Dine condensate collapse

International Nuclear Information System (INIS)

Enqvist, Kari; McDonald, John

2000-01-01

In the MSSM, cosmological scalar field condensates formed along flat directions of the scalar potential (Affleck-Dine condensates) are typically unstable with respect to formation of Q-balls, a type of non-topological soliton. We consider the dynamical evolution of the Affleck-Dine condensate in the MSSM. We discuss the creation and linear growth, in F- and D-term inflation models, of the quantum seed perturbations which in the non-linear regime catalyse the collapse of the condensate to non-topological soliton lumps. We study numerically the evolution of the collapsing condensate lumps and show that the solitons initially formed are not in general Q-balls, but Q-axitons, a pseudo-breather which can have very different properties from Q-balls of the same charge. We calculate the energy and charge radiated from a spherically symmetric condensate lump as it evolves into a Q-axiton. We also discuss the implications for baryogenesis and dark matter

Air-breathing fishes in aquaculture. What can we learn from physiology?

Science.gov (United States)

Lefevre, S; Wang, T; Jensen, A; Cong, N V; Huong, D T T; Phuong, N T; Bayley, M

2014-03-01

During the past decade, the culture of air-breathing fish species has increased dramatically and is now a significant global source of protein for human consumption. This development has generated a need for specific information on how to maximize growth and minimize the environmental effect of culture systems. Here, the existing data on metabolism in air-breathing fishes are reviewed, with the aim of shedding new light on the oxygen requirements of air-breathing fishes in aquaculture, reaching the conclusion that aquatic oxygenation is much more important than previously assumed. In addition, the possible effects on growth of the recurrent exposure to deep hypoxia and associated elevated concentrations of carbon dioxide, ammonia and nitrite, that occurs in the culture ponds used for air-breathing fishes, are discussed. Where data on air-breathing fishes are simply lacking, data for a few water-breathing species will be reviewed, to put the physiological effects into a growth perspective. It is argued that an understanding of air-breathing fishes' respiratory physiology, including metabolic rate, partitioning of oxygen uptake from air and water in facultative air breathers, the critical oxygen tension, can provide important input for the optimization of culture practices. Given the growing importance of air breathers in aquaculture production, there is an urgent need for further data on these issues. © 2014 The Fisheries Society of the British Isles.

Detection of bronchial breathing caused by pneumonia.

Science.gov (United States)

Gross, V; Fachinger, P; Penzel, Th; Koehler, U; von Wichert, P; Vogelmeier, C

2002-06-01

The classic auscultation with stethoscope is the established clinical method for the detection of lung diseases. The interpretation of the sounds depends on the experience of the investigating physician. Therefore, a new computer-based method has been developed to classify breath sounds from digital lung sound recordings. Lung sounds of 11 patients with one-sided pneumonia and bronchial breathing were recorded on both the pneumonia side and on contralateral healthy side simultaneously using two microphones. The spectral power for the 300-600 Hz frequency band was computed for four respiratory cycles and normalized. For each breath, the ratio R between the time-segments (duration = 0.1 s) with the highest inspiratory and highest expiratory flow was calculated and averaged. We found significant differences in R between the pneumonia side (R = 1.4 +/- 1.3) and the healthy side (R = 0.5 +/- 0.5; p = 0.003 Wilcoxon-test) of lung. In 218 healthy volunteers we found R = 0.3 +/- 0.2 as a reference-value. The differences of ratio R (delta R) between the pneumonia side and the healthy side (delta R = 1.0 +/- 0.9) were significantly higher compared to follow-up studies after recovery (delta R = 0.0 +/- 0.1, p = 0.005 Wilcoxon-test). The computer based detection of bronchial breathing can be considered useful as part of a quantitative monitoring of patients at risk to develop pneumonia.

Measurement and prediction of indoor air quality using a breathing thermal manikin

DEFF Research Database (Denmark)

Melikov, Arsen Krikor; Kaczmarczyk, J.

2007-01-01

temperature is sensitive enough to perform reliable measurement of characteristics of air as inhaled by occupants. The temperature, humidity, and pollution concentration in the inhaled air can be measured accurately with a thermal manikin without breathing simulation if they are measured at the upper lip...... at a distance of measured inhaled air parameters. Proper simulation of breathing, especially of exhalation, is needed for studying the transport of exhaled air between occupants. A method......The analyses performed in this paper reveal that a breathing thermal manikin with realistic simulation of respiration including breathing cycle, pulmonary ventilation rate, frequency and breathing mode, gas concentration, humidity and temperature of exhaled air and human body shape and surface...

Fast-starting after a breath: air-breathing motions are kinematically similar to escape responses in the catfish Hoplosternum littorale

Directory of Open Access Journals (Sweden)

Paolo Domenici

2014-12-01

Full Text Available Fast-starts are brief accelerations commonly observed in fish within the context of predator–prey interactions. In typical C-start escape responses, fish react to a threatening stimulus by bending their body into a C-shape during the first muscle contraction (i.e. stage 1 which provides a sudden acceleration away from the stimulus. Recently, similar C-starts have been recorded in fish aiming at a prey. Little is known about C-starts outside the context of predator–prey interactions, though recent work has shown that escape response can also be induced by high temperature. Here, we test the hypothesis that air-breathing fish may use C-starts in the context of gulping air at the surface. Hoplosternum littorale is an air-breathing freshwater catfish found in South America. Field video observations reveal that their air-breathing behaviour consists of air-gulping at the surface, followed by a fast turn which re-directs the fish towards the bottom. Using high-speed video in the laboratory, we compared the kinematics of the turn immediately following air-gulping performed by H. littorale in normoxia with those of mechanically-triggered C-start escape responses and with routine (i.e. spontaneous turns. Our results show that air-breathing events overlap considerably with escape responses with a large stage 1 angle in terms of turning rates, distance covered and the relationship between these rates. Therefore, these two behaviours can be considered kinematically comparable, suggesting that air-breathing in this species is followed by escape-like C-start motions, presumably to minimise time at the surface and exposure to avian predators. These findings show that C-starts can occur in a variety of contexts in which fish may need to get away from areas of potential danger.

Breathing difficulty - lying down

Science.gov (United States)

... other conditions that lead to it) Panic disorder Sleep apnea Snoring Home Care Your health care provider may recommend self-care measures. For example, weight loss may be suggested if you are obese. When to Contact a Medical Professional If you have any unexplained difficulty in breathing ...

A study on passive containment cooling condensers in SBWR

International Nuclear Information System (INIS)

Kuran, S.; Soekmen; C. N.

2001-01-01

The passive containment cooling condensers (PCCC) are the crucial part of several new reactor designs, like European Simplified Boiling Water Reactor (ESBWR) and the SBWR. In a hypothetical accident, the pressurised steam non-condensable mixture from drywell is condensed in PCCCs, and condensate is returned to reactor vessel while non-condensable is vented through wet well. In this study, in order to examine the performance of PCCCs, condensation with presence of noncondensable is investigated. Condensation with different noncondensable types and conditions is studied on a PCCC model, which is developed by using RELAP5 Mod3.2 computer code

The breathtaking truth about breath alcohol readings of zero

NARCIS (Netherlands)

Verster, Joris C; Mackus, Marlou; van de Loo, Aurora Jae; Garssen, Johan; Scholey, Andrew

INTRODUCTION: It has been postulated that the hangover state starts when breath alcohol concentration is zero. METHODS: Data from 2 studies that assessed ethanol in breath, blood and urine were compared. RESULTS: The data revealed that ethanol may still be present in the blood and urine during the

How Important Is a Reproducible Breath Hold for Deep Inspiration Breath Hold Breast Radiation Therapy?

International Nuclear Information System (INIS)

Wiant, David; Wentworth, Stacy; Liu, Han; Sintay, Benjamin

2015-01-01

Purpose: Deep inspiration breath hold (DIBH) for left-sided breast cancer has been shown to reduce heart dose. Surface imaging helps to ensure accurate breast positioning, but it does not guarantee a reproducible breath hold (BH) at DIBH treatments. We examine the effects of variable BH positions for DIBH treatments. Methods and Materials: Twenty-five patients who underwent free breathing (FB) and DIBH scans were reviewed. Four plans were created for each patient: FB, DIBH, FB-DIBH (the DIBH plans were copied to the FB images and recalculated, and image registration was based on breast tissue), and P-DIBH (a partial BH with the heart shifted midway between the FB and DIBH positions). The FB-DIBH plans give a “worst-case” scenario for surface imaging DIBH, where the breast is aligned by surface imaging but the patient is not holding their breath. Kolmogorov-Smirnov tests were used to compare the dose metrics. Results: The DIBH plans gave lower heart dose and comparable breast coverage versus FB in all cases. The FB-DIBH plans showed no significant difference versus FB plans for breast coverage, mean heart dose, or maximum heart dose (P≥.10). The mean heart dose differed between FB-DIBH and FB by <2 Gy for all cases, and the maximum heart dose differed by <2 Gy for 21 cases. The P-DIBH plans showed significantly lower mean heart dose than FB (P<.01). The mean heart doses for the P-DIBH plans were < FB for 22 cases, the maximum dose was < FB for 18 cases. Conclusions: A DIBH plan delivered to a FB patient setup with surface imaging will yield dosimetry similar to that of a plan created and delivered FB. A DIBH plan delivered with even a partial BH can give reduced heart dose compared with FB techniques.

How Important Is a Reproducible Breath Hold for Deep Inspiration Breath Hold Breast Radiation Therapy?

Energy Technology Data Exchange (ETDEWEB)

Wiant, David, E-mail: David.wiant@conehealth.com; Wentworth, Stacy; Liu, Han; Sintay, Benjamin

2015-11-15

Purpose: Deep inspiration breath hold (DIBH) for left-sided breast cancer has been shown to reduce heart dose. Surface imaging helps to ensure accurate breast positioning, but it does not guarantee a reproducible breath hold (BH) at DIBH treatments. We examine the effects of variable BH positions for DIBH treatments. Methods and Materials: Twenty-five patients who underwent free breathing (FB) and DIBH scans were reviewed. Four plans were created for each patient: FB, DIBH, FB-DIBH (the DIBH plans were copied to the FB images and recalculated, and image registration was based on breast tissue), and P-DIBH (a partial BH with the heart shifted midway between the FB and DIBH positions). The FB-DIBH plans give a “worst-case” scenario for surface imaging DIBH, where the breast is aligned by surface imaging but the patient is not holding their breath. Kolmogorov-Smirnov tests were used to compare the dose metrics. Results: The DIBH plans gave lower heart dose and comparable breast coverage versus FB in all cases. The FB-DIBH plans showed no significant difference versus FB plans for breast coverage, mean heart dose, or maximum heart dose (P≥.10). The mean heart dose differed between FB-DIBH and FB by <2 Gy for all cases, and the maximum heart dose differed by <2 Gy for 21 cases. The P-DIBH plans showed significantly lower mean heart dose than FB (P<.01). The mean heart doses for the P-DIBH plans were

Coherence and chaos in condensed matter

International Nuclear Information System (INIS)

Bishop, A.R.

1989-01-01

This paper discusses the following topics: nonlinearity in condensed matter; coherence and chaos in spatially extended condensed matter systems; nonlinearity and magnetism; and solitons and conducting polymers. 52 refs., 7 figs

Breath-hold gadolinium-enhanced MRA : clinical application

International Nuclear Information System (INIS)

Kang, Sung Gwon; Kang, Ji Hee; Kim, Won Hong; Lim, Myung Kwan; Cho, Young Kook; Cho, Soon Gu; Suh, Chang Hae

1998-01-01

The purpose of this study is to compare breath-hold gadolinium enhanced MR angiography (MRA) with digital subtraction angiography. Ten patients underwent angiography and breath-hold gadolinium enhanced MRA; the latter performed at 1.5T with 3D FSPGR after a bolus injection of gadopentetate dimeglumine (0.4m mol/kg). Seven of ten pathologic conditions (70%) evaluated by both techniques had a similar appearance. The conditions examined were as follows: the artery feeding renal cell carcinoma(n=2); renal artery stenosis (n=2); pulmonary AVM(n=2); abdominal aortic aneurysm (n=1); atheromatous plaque in the lower abdominal aorta (n=1); an enlarged bronchial artery (n=1); and an aberrant renal artery (n=1). For evaluating an anatomic relationship, a reconstructed 3D image obtained by MRA is more advantageous. Breath hold contrast enhanced MRA is a potentially useful noninvasive screening method for detecting vascular abnormality of the aorta and its branches. (author). 13 refs., 1 tab., 4 figs

Breath-hold gadolinium-enhanced MRA : clinical application

Energy Technology Data Exchange (ETDEWEB)

Kang, Sung Gwon; Kang, Ji Hee; Kim, Won Hong; Lim, Myung Kwan; Cho, Young Kook; Cho, Soon Gu; Suh, Chang Hae [Inha University Hospital, Inchon (Korea, Republic of)

1998-05-01

The purpose of this study is to compare breath-hold gadolinium enhanced MR angiography (MRA) with digital subtraction angiography. Ten patients underwent angiography and breath-hold gadolinium enhanced MRA; the latter performed at 1.5T with 3D FSPGR after a bolus injection of gadopentetate dimeglumine (0.4m mol/kg). Seven of ten pathologic conditions (70%) evaluated by both techniques had a similar appearance. The conditions examined were as follows: the artery feeding renal cell carcinoma(n=2); renal artery stenosis (n=2); pulmonary AVM(n=2); abdominal aortic aneurysm (n=1); atheromatous plaque in the lower abdominal aorta (n=1); an enlarged bronchial artery (n=1); and an aberrant renal artery (n=1). For evaluating an anatomic relationship, a reconstructed 3D image obtained by MRA is more advantageous. Breath hold contrast enhanced MRA is a potentially useful noninvasive screening method for detecting vascular abnormality of the aorta and its branches. (author). 13 refs., 1 tab., 4 figs.

Molecular simulation of steady-state evaporation and condensation in the presence of a non-condensable gas

Science.gov (United States)

Liang, Zhi; Keblinski, Pawel

2018-02-01

Using molecular dynamics simulations, we study evaporation and condensation of fluid Ar in the presence of a non-condensable Ne gas in a nanochannel. The evaporation and condensation are driven by the temperature difference, ΔTL, between the evaporating and condensing liquid surfaces. The steady-state evaporation and condensation fluxes (JMD) are also affected by the Ne concentration, ρNe, and the nanochannel length. We find that across a wide range of ΔTL and ρNe, JMD is in good agreement with the prediction from Stefan's law and from Schrage relationships. Furthermore, for ΔTL less than ˜20% of the absolute average temperature, we find that both steady-state heat and mass fluxes are proportional to ΔTL. This allows us to determine the interfacial resistance to the heat and mass transfer and compare it with the corresponding resistances in the gas phase. In this context, we derive an analytical expression for the effective thermal conductivity of the gas region in the nanochannel and the mass transport interfacial resistance equivalent length, i.e., the length of the nanochannel for which the resistance to the mass flow is the same as the interfacial resistance to the mass flow.

Development and Evaluation of Algorithms for Breath Alcohol Screening.

Science.gov (United States)

Ljungblad, Jonas; Hök, Bertil; Ekström, Mikael

2016-04-01

Breath alcohol screening is important for traffic safety, access control and other areas of health promotion. A family of sensor devices useful for these purposes is being developed and evaluated. This paper is focusing on algorithms for the determination of breath alcohol concentration in diluted breath samples using carbon dioxide to compensate for the dilution. The examined algorithms make use of signal averaging, weighting and personalization to reduce estimation errors. Evaluation has been performed by using data from a previously conducted human study. It is concluded that these features in combination will significantly reduce the random error compared to the signal averaging algorithm taken alone.

Universe out of a breathing bubble

International Nuclear Information System (INIS)

Guendelman, Eduardo I.; Sakai, Nobuyuki

2008-01-01

We consider the model of a false-vacuum bubble with a thin wall where the surface energy density is composed of two different components, 'domain-wall' type and 'dust' type, with opposite signs. We find stably oscillating solutions, which we call 'breathing bubbles'. By decay to a lower mass state, such a breathing bubble could become either (i) a child universe or ii) a bubble that 'eats up' the original universe, depending on the sign of the surface energy of the domain-wall component. We also discuss the effect of the finite-thickness corrections to the thin-wall approximation and possible origins of the energy contents of our model

Secondary side water chemistry pH control strategy improvements

International Nuclear Information System (INIS)

Roumiguiere, Fernando-Mario; Fandrich, Joerg; Ramminger, Ute; Hoffmann-Wankerl, Stephan; Drexler, Andreas

2012-09-01

Over the years the PWR plant operators were aware of the need of optimizing the pH control strategy in the water-steam cycle with the focus on improvement of steam generator performance with the main goal of reducing the corrosion product ingress into the steam generators and their consequences: SG fouling, SG tube corrosion beneath deposits. To achieve this goal, it becomes necessary to harmonize three requirements: a. High overall pH along the circuit for suppression of general corrosion, requiring a volatile amine to ensure a suitable distribution in steam areas and condenser, and b. High local pH at the water phase of two-phase flow areas, requiring an either rather low volatile amine to ensure high pH in the wet steam water film, or larger amounts of a volatile amine. c. Sufficient amount of hydrazine to ensure reducing conditions in the steam generators. The basic strategy of AREVA NP GmbH (formerly KWU), successfully applied in German nuclear power plants since the late seventies consisted on the achievement of the necessary pH by means of ammonia, as generated by thermal decomposition of hydrazine. By dosing of hydrazine at the necessary amounts to ensure reducing conditions, also sufficient ammonia is generated to achieve a high overall pH along the cycle, being the target pH (25 deg. C) ≥ 9.8 resulting in < 1 ppb Fe in final feed water. This treatment is known as H-AVT (High pH - All Volatile Treatment). Main prerequisite for its application is to have a copper-free system. Eventually, H-AVT started to be applied later at some other western nuclear power plants. In some units, the high condenser exhaust flow rate applied caused a considerable amount of ammonia being removed from the cycle, resulting in too low ammonia concentrations to maintain a sufficiently high pH, making the addition of ammonia necessary. AREVA NP GmbH together with plant operators investigated the possibility of complementing the applied classical H-AVT by addition of an advanced

Health, social and economical consequences of sleep-disordered breathing

DEFF Research Database (Denmark)

Jennum, Poul; Kjellberg, Jakob

2011-01-01

The objective direct and indirect costs of sleep-disordered breathing (snoring, sleep apnoea (SA) and obesity hypoventilation syndrome (OHS)) and the treatment are incompletely described.......The objective direct and indirect costs of sleep-disordered breathing (snoring, sleep apnoea (SA) and obesity hypoventilation syndrome (OHS)) and the treatment are incompletely described....

Association between breastfeeding and breathing pattern in children: a sectional study

Directory of Open Access Journals (Sweden)

Teresinha S.P. Lopes

2014-07-01

Full Text Available OBJECTIVE: to determine the prevalence of mouth breathing and to associate the history of breastfeeding with breathing patterns in children. METHODS: this was an observational study with 252 children of both genders, aged 30 to 48 months, who participated in a dental care program for mothers and newborns. As an instrument of data collection, a semi-structured questionnaire was administered to the children's mothers assessing the form and duration of breastfeeding and the oral habits of non-nutritive sucking. To determine the breathing patterns that the children had developed, medical history and clinical examination were used. Statistical analysis was conducted to examine the effects of exposure on the primary outcome (mouth breathing, and the prevalence ratio was calculated with a 95% confidence interval. RESULTS: of the total sample, 43.1% of the children were mouth breathers, 48.4% had been breastfed exclusively until six months of age or more, and 27.4% had non-nutritive sucking habits. Statistically significant associations were found for bottle-feeding (p < 0.001 and oral habits of non-nutritive sucking (p = 0.009, with an increased likelihood of children exhibiting a predominantly oral breathing pattern. A statistically significant association was also observed between a longer duration of exclusive breastfeeding and a nasal breathing pattern presented by children. CONCLUSION: an increased duration of exclusive breastfeeding lowers the chances of children exhibiting a predominantly oral breathing pattern.

The phase transition to an inhomogeneous condensate state

International Nuclear Information System (INIS)

Voskresensky, D.N.

1984-01-01

The Lagrangian (free energy) of the model with a complex scalar order parameter in which the phase transition to an inhomogeneous condensate state exists is constructed in the coordinate representation. In the case of condensation of charged particles (for example paired electrons) interaction with the electromagnetic field is included. The excitation spectrum in the presence of the condensate is found. The oscillations are strongly anisotropic. It is shown that superfluidity is absent for an uncharged system but that the charged one has the property of superconductivity. The important role of thermal fluctuations is demonstrated. They drastically change the behaviour of the condensate system. The condensation in a finite system is considered. A study is carried out for the behaviour of an inhomogeneous condensate in magnetic field. It is shown that the inhomogeneous condensate is a type II superconductor with Ginzburg-Landau parameter kappa >> 1, but that the structure of the mixed state of the system is unusual - consisting of plane layers of the normal phase, when Hsub(c1)< H< H'sub(c2). The distribution of condensate in the strong magnetic field H'sub(c2)< H< Hsub(c2) is also studied. (Auth.)

Deepak Condenser Model (DeCoM)

Science.gov (United States)

Patel, Deepak

2013-01-01

Development of the DeCoM comes from the requirement of analyzing the performance of a condenser. A component of a loop heat pipe (LHP), the condenser, is interfaced with the radiator in order to reject heat. DeCoM simulates the condenser, with certain input parameters. Systems Improved Numerical Differencing Analyzer (SINDA), a thermal analysis software, calculates the adjoining component temperatures, based on the DeCoM parameters and interface temperatures to the radiator. Application of DeCoM is (at the time of this reporting) restricted to small-scale analysis, without the need for in-depth LHP component integrations. To efficiently develop a model to simulate the LHP condenser, DeCoM was developed to meet this purpose with least complexity. DeCoM is a single-condenser, single-pass simulator for analyzing its behavior. The analysis is done based on the interactions between condenser fluid, the wall, and the interface between the wall and the radiator. DeCoM is based on conservation of energy, two-phase equations, and flow equations. For two-phase, the Lockhart- Martinelli correlation has been used in order to calculate the convection value between fluid and wall. Software such as SINDA (for thermal analysis analysis) and Thermal Desktop (for modeling) are required. DeCoM also includes the ability to implement a condenser into a thermal model with the capability of understanding the code process and being edited to user-specific needs. DeCoM requires no license, and is an open-source code. Advantages to DeCoM include time dependency, reliability, and the ability for the user to view the code process and edit to their needs.