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Asakawa Takashi T Department of Chemical System Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan. - - 2010
We have investigated the pressure dependence of the detection sensitivity of CO(2), N(2)O and CH(4) using wavelength modulation spectroscopy (WMS) with distributed feed-back diode lasers in the near infrared region. The spectral line shapes and the background noise of the second harmonics (2f) detection of the WMS were analyzed theoretically. ...
Wagner A J - - 2009
Electrical characterization of a nonthermal radio-frequency atmospheric-pressure microplasma in a parallel plate configuration has shown that reducing electrode gap into the submillimeter range increases current and power density at a reduced voltage as compared to similar plasmas at larger electrode gaps which have no gap dependence. Calculation of sheath thickness ...
Marinovic Jasna - - 2009
INTRODUCTION: The use of trimix (a mixture of oxygen, helium, and nitrogen) has significantly increased among the diver population. However, data indicating how trimix dives at most common depths affect the cardiovascular function are sparse. The purpose of this study was to investigate the cardiovascular effects of trimix dives and ...
Xu Lihua - - 2010
Surface-initiated graft polymerization on multi-walled carbon nanotubes pretreated with a corona discharge at atmospheric pressure was explored. The mechanism of the corona-discharge-induced graft polymerization is discussed. The results indicate that MWCNTs were encapsulated by poly(glycidyl methacrylate) (PGMA), demonstrating the formation of PGMA-grafted MWCNTs (PGMA-g-MWCNTs), with a grafting ratio of about ...
Sohbatzadeh Farshad - - 2010
We developed and employed a new geometrical structure of dielectric barrier discharge in atmospheric pressure for bacterial broad spectrum sterilization. We utilized a plasma source having an AC power supply at 50 HZ and 5,400 V (rms value). We prepared suspensions of the Gram-negative bacteria species (Escherichia coli, Pseudomonas aeruginosa) ...
Covey Thomas R - - 2009
This review of atmospheric pressure ion sources discusses major developments that have occurred since 1991. Advances in the instrumentation and understanding of the key physical principles are the primary focus. Developments with electrospray and atmospheric pressure chemical ionization and variations encompassing adaptations for surface analysis, ambient air analysis, high throughput, ...
Martens Tom - - 2009
We have investigated the plasma processes in an atmospheric pressure glow discharge (APGD) in He used for analytical spectrometry by means of fluid and Monte Carlo (MC) simulations. Typical results include the potential and electric field distributions in the plasma, the density profiles of the various plasma species throughout the ...
Chio Chi Hong - - 2010
The stability of synthetic Jarosite (KFe(3)(SO(4))(2)(OH)(6)) at low temperature and reduced atmospheric pressure has been studied by Raman spectroscopy. Jarosite remains stable between 8 and 295 K, provided that the sample is not exposed to reduced atmospheric pressure. When exposed to reduced atmospheric pressure (2.0x10(-2) Torr), however, the conversion of ...
Gao Liang - - 2010
Axial collision induced dissociation (CID) and high-pressure resonance CID were implemented and compared with normal low-pressure resonance CID in a miniature ion trap mass spectrometer to obtain more complete fragmentation spectra. Axial CID was realized simply by applying a potential to the discontinuous atmospheric pressure interface (DAPI) capillary without performing ...
Brown Helen K - - 2009
The influence of weather on deep venous thrombosis (DVT) incidence remains controversial. We aimed to characterize the temporal association between DVT and meteorological variables including atmospheric pressure. Data relating to hospital admissions with DVT in Scotland were collected retrospectively for a 20 year period for which corresponding meteorological recordings were ...
Schieman Colin - - 2009
BACKGROUND: Spontaneous pneumothorax (SP) results from the rupture of blebs or emphysematous bullae. Rapid changes in weather may precipitate this process. The city of Calgary is well suited to examine the effects of weather and specifically the rapid changes in weather associated with a chinook event and the occurrence of ...
Sakamoto Yosuke - - 2009
Cavity ring-down spectroscopy was used to study the title reaction in 50-200 Torr of O2 diluent at 233-333 K. There was no discernible effect of total pressure, and a rate constant of k(BrO + C2H5O2) = (3.8 +/- 1.7) x 10(-12) cm3 molecule(-1) s(-1) was determined at 293 K in ...
Mireku Nana - - 2009
BACKGROUND: Pediatric asthma exacerbations may correlate with changes in weather, yet this relationship is not well defined. OBJECTIVE: To determine the effects of fluctuations in climatic factors (temperature, humidity, and barometric pressure) on pediatric asthma exacerbations. METHODS: A retrospective study was performed at 1 large urban hospital during a 2-year ...
Li Yue - - 2009
The effect of outdoor clothing and repeated cold exposure on blood pressure, heart rate, skin temperature, and thermal sensation was studied in 16 young (18-34 years) and 8 middle-aged (35-51 years) normotensive participants. Four winter clothing ensembles were used: regular winter clothing without a hat, with a hat, with an ...
Sieber Arne - - 2009
Knowledge regarding arterial blood pressure (ABP) values during breath-hold diving is scanty. It derives from a few reports of measurements performed at the water's surface, showing slight or no increase in ABP, and from a single study of two simulated deep breath-hold dives in a hyperbaric chamber. Simulated dives showed ...
Bozeman W P - - 2009
STUDY OBJECTIVES: To evaluate the immediate cardiac and cardiovascular effects of Taser X26 conducted electrical weapon (CEW) exposure in human volunteers, including heart rhythm, rate and blood pressure. METHODS: Volunteer police officers participating in CEW training and testing each underwent a 5, 3 and 1 s exposure to the Taser ...
Grassi Paolo - - 2009
INTRODUCTION: Hyperbaric environment exposure in humans has cardiovascular effects mainly characterized by an increase in afterload and a decrease in cardiac output. In a previous study we did not find B-type natriuretic peptide (BNP) changes in healthy volunteers exposed to hyperbaric oxygen while other authors documented a significant increase in ...
Brook Robert D RD University of Michigan, 24 Frank Lloyd Wright Drive, Ann Arbor, MI 48106, USA. - - 2009
Fine particulate matter air pollution plus ozone impairs vascular function and raises diastolic blood pressure. We aimed to determine the mechanism and air pollutant responsible. The effects of pollution on heart rate variability, blood pressure, biomarkers, and brachial flow-mediated dilatation were determined in 2 randomized, double-blind, crossover studies. In Ann ...
Doherty M J - - 2009
In a prior study of epilepsy and atmospheric pressure, we were able to show a small association between changes in atmospheric pressure and increased seizure frequency in consecutive patients with epilepsy undergoing video telemetry. In this study, we used a larger data set of similar patients undergoing telemetry at another ...
Connor Christopher W - - 2009
The U.S. Navy recommends submarine escape for depths down to 600 fsw, with deeper escapes entailing the risks of decompression sickness, nitrogen (N2) narcosis and CNS oxygen (O2) toxicity. However, the escape equipment, including the submarine escape and immersion equipment and the escape trunk, could probably function even at 1,000 ...
Wu Yiquan - - 2009
Electrospraying is a simple and versatile technique capable of producing polymeric particles. However, most investigations carried out thus far have been performed at ambient atmospheric pressure without studying the influences of pressure on the formation of polymeric particles. Here, we report our investigation on the effects of varying the pressure ...
Parra Jeremy - - 2009
Concerns about the health effects of nitrogen dioxide (NO2) and its role in forming deleterious atmospheric species have made it desirable to have low-cost, sensitive ambient measurements of NO2. We have developed a continuous-wave laser-diode laser-induced fluorescence (LIF) system for NO2 that operates at ambient pressure, thereby eliminating the need ...
Ernst Michael E - - 2009
Changes in atmospheric pressure may influence hepatic blood flow and drug metabolism. Anecdotal experience suggests international normalized ratio (INR) variability may be temporally related to significant atmospheric pressure changes. We investigated this potential association in a large sample of patients with multiple INRs. This is a retrospective review of outpatient ...
Li King-Fai - - 2009
Lovelock and Whitfield suggested in 1982 that, as the luminosity of the Sun increases over its life cycle, biologically enhanced silicate weathering is able to reduce the concentration of atmospheric carbon dioxide (CO(2)) so that the Earth's surface temperature is maintained within an inhabitable range. As this process continues, however, ...
Styra D - - 2009
The prognostic relationship between a decrease of hard cosmic ray flux (HCRF) and subsequent leaps in cardiovascular disease (CVD) occurrence within 1-3 days is well known. The influence of meteorological situations on human health is also known. However, no correlation was found between a simultaneous decrease of HCRF and atmospheric ...
Jiang Jianguo - - 2009
There are special requirements for municipal solid waste (MSW) treatment caused by lower oxygen content and atmospheric pressure on the Altiplano. The intention of this paper was to analyse the applicability of various technologies to MSW treatment in the Altiplano and select the best one based on the current MSW ...
Liu W - - 2009
Contradictory reports exist regarding the effects of hyperbaric oxygen (HBO2) on immune functions. We hypothesized that the intensity of exposure is a key factor, which leads to the different effects of HBO2 on immunity. In this study, we determined the function of rat splenic lymphocytes after in vitro exposure to ...
Benedikt J - - 2009
A novel method of reducing the background pressure in a vacuum system used for sampling a molecular beam from a high pressure region is presented. A triple differential pumping stage is constructed with a chopper with rotating skimmer within the first pumping stage, which serves effectively as a valve separating ...
Paz-Schmidt Roberto A - - 2009
A new approach for real-time mass spectrometric analysis and identification of intermediates in confined, pressurized vessels is presented. The high-pressure reaction media is depressurized, mixed with a solvent, and fed directly to the atmospheric pressure electrospray ionization source of a tandem mass spectrometer. The method was applied to track product ...
Ozpolat Berkant - - 2009
Spontaneous pneumothorax is defined as the rupture of bleb or emphysematous bullae that develop just beneath the pulmonary pleura. Weather changes may influence the incidence of spontaneous pneumothorax. The aim of this study was to examine the influence of rainfall, temperature and atmospheric pressure changes on the onset of spontaneous ...
Arieli R - - 2009
We previously hypothesized that the number of bubbles emerging on decompression from a dive, and the resultant risk of decompression sickness (DCS), may be reduced by a process whereby effective gas micronuclei that might otherwise have formed bubbles on decompression are shrunk and eliminated. In a procedure defined by us ...
Kolling Derrick R J - - 2009
We investigated the effects of elevated O(2) pressure on the production of O(2) by photosynthetic organisms in several species of plants, algae, and a cyanobacterium. Using a noninvasive fluorometry technique to monitor sequential turnover of the photosystem II (PSII) reaction center as a function of O(2) pressures, we showed that ...
Mourot L - - 2009
This study was aimed at investigating whether repeated SCUBA diving might induce long term cardiovascular and autonomic modifications. In 11 military mine clearance diving students, arterial compliance (ultrasound scan study of brachial artery and ratio of stroke volume to pulse pressure: SV/PP), resting spectral analyses of heart rate and blood ...
Little Uel - - 2009
The role of roughening and functionalization processes involved in modifying the wettability of poly(epsilon-caprolactone) (PCL) after treatment by an atmospheric pressure glow discharge plasma is discussed. The change in the ratio of CO/C-O bonds is a significant factor influencing the wettability of PCL. As the contact angle decreases, the level ...
Dunkelberg Hartmut - - 2009
OBJECTIVE: The sterility assurance level of 10(-6) is an established standard that defines the quality of sterile products. The aim of the present study was to develop a method that correlated the results from microbial-barrier testing of flexible sterile barrier systems with the estimated microbial challenge that the package encounters ...
Zou Q - - 2009
Electron field emission (FE) from carbon nanotubes (CNTs) in air for excitation of atmospheric pressure microplasma was investigated in a scanning electron microscope (SEM). The results showed that, the FE properties of CNTs at 10 kPa and lower pressures were the same as those in vacuum. At pressures more than ...
Raghukumar, C.
Two species of filamentous fungi, Aspergillus ustus (Bain.) Thoms and Church and Graphium sp., were isolated from calcareous animal shells at depths of 860 m in the Arabian Sea and 965 m in the Bay of Bengal. Laboratory experiments showed germination of conidia, growth of hyphae and microconidiation in both ...
Yun Ju-Hyung - - 2009
Highly sensitive palladium (Pd) decorated carbon nanotube (CNT) embedding gas sensors working at atmospheric pressure were fabricated. Two types of gas sensors of bare CNTs and Pd nanoparticle decorated CNTs were synthesized by dielectrophoresis. The CNT-containing solution was dropped onto the patterned-platinum electrodes with ac bias. The CNT-embedding sensors sensitively ...
Sierra Rocio - - 2009
Lime pretreatment has proven to be a useful method for selectively reducing the lignin content of lignocellulosic biomass without significant loss in carbohydrates, thus realizing an important increase in biodigestibility. In lime pretreatment, the biomass is pretreated with calcium hydroxide and water under different conditions of temperature and pressure. It ...
Johnson G A - - 2009
The weight change per actuation and aerosol particle size and number delivered by albuterol metered dose inhalers (MDIs) were measured in a multiplace hyperbaric chamber at pressures ranging from one atmosphere absolute (1 ATA, 0 feet of seawater, fsw, 101 kPa) to three ATA (66 fsw, 304 kPa). Weight change ...
Reinstein Shelby - - 2009
Canine glaucoma encompasses a diverse group of diseases associated with an increase in intraocular pressure that results in retinal ganglion cell death and eventual blindness. Dogs may have congenital, primary, or secondary glaucoma. The diagnosis is made by recognizing clinical signs, interpreting ophthalmic examination findings, and determining intraocular pressure. Identifying ...
Blatteau Jean-Eric - - 2008
INTRODUCTION: This study investigated the influence of a far infrared-ray dry sauna-induced heat exposure before a simulated dive on bubble formation, and examined the concomitant adjustments in hemodynamic parameters. METHODS: There were 16 divers who were compressed in a hyperbaric chamber to 400 kPa (30 msw) for 25 min and ...
Sébert P - - 2009
To reproduce, European eels must undergo a long migration without feeding. During this migration they have to cope with many environmental factor changes, one of them being hydrostatic pressure. We focus on the effects of hydrostatic pressure on swimming energetics: does the pressure exposure modify swimming efficiency? By using a ...
Pointu, Anne-Marie
A nitrogen afterglow at atmospheric pressure has recently been described as able to transport active species over long distances in small diameter tubes, with a biocidal effect. For a discharge gas composed of nitrogen, either of high purity or with some controlled ppm of oxygen, survival curves are presented. The ...
Watson Donald A - - 2008
A mild, functional group tolerant method of the preparation of phenyl esters from aryl chlorides via palladium-catalyzed carbonylation is described using atmospheric pressure of carbon monoxide. Phenyl esters are shown to be useful acylating agents, delivering libraries of carbonyl derivatives, including alkyl, allyl and thioesters, under very mild conditions. Direct ...
Miller Thomas L - - 2008
We tested the hypothesis that hyperoxia or pressure exposure differentially activates expression of cytokines and/or matrix modeling proteins in human airway epithelial cells. Calu-3 epithelial cell monolayers were cultured on transwell plates with the apical surface exposed to gas. Following establishment of baseline, plates were placed in a chamber and ...
Smith R A - - 2008
INTRODUCTION: Seasonal variation in rates of abdominal aortic aneurysm (AAA) rupture has previously been described. However, only two studies, to date, have suggested that periods of low atmospheric pressure may account for this observation and both returned apparently contradictory findings. The objective of this study was to demonstrate whether periods ...
Peretz Alon - - 2008
Traffic-related air pollution is consistently associated with cardiovascular morbidity and mortality. Recent human and animal studies suggest that exposure to air pollutants affects vascular function. Diesel exhaust (DE) is a major source of traffic-related air pollution. Our goal was to study the effects of short-term exposure to DE on vascular ...
Killeen S D - - 2008
BACKGROUND: Ruptured abdominal aortic aneurysm (RAAA) presents with increased frequency in the winter and spring months. Seasonal changes in atmospheric pressure mirrors this pattern. AIM: To establish if there was a seasonal variation in the occurrence of RAAA and to determine if there was any association with atmospheric pressure changes. ...
Jensen Lars Liengaard - - 2008
We describe the design, construction, and pilot operation of a Mars simulation facility comprised of a cryogenic environmental chamber, an atmospheric gas analyzer, and a xenon/mercury discharge source for UV generation. The Mars Environmental Simulation Chamber (MESCH) consists of a double-walled cylindrical chamber. The double wall provides a cooling mantle ...
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