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Results 251 - 300 of 1047
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Bodkin J J - - 2006
Negative pressure breathing (NPB) increases the rate of nitrogen elimination, which is thought to be due to an increase in cardiac output due to augmented venous return to the heart. Hyperoxia, however, decreases the rate of nitrogen elimination. The effect of hyperoxia on the increase in nitrogen elimination during NPB ...
Antognini Joseph F JF Department of Anesthesiology and Pain Medicine, University of California, Davis, TB-170, Davis, CA 95616, USA. - - 2007
The limited potency of nitrous oxide mandates the use of a hyperbaric chamber to produce anesthesia. Use of a hyperbaric chamber complicates anesthetic delivery, ventilation, and electrophysiological recording. We constructed a hyperbaric acrylic-aluminum chamber allowing recording of single unit activity in spinal cord of rats anesthetized only with N(2)O. Large ...
Bousquet P - - 2006
Methane is an important greenhouse gas, and its atmospheric concentration has nearly tripled since pre-industrial times. The growth rate of atmospheric methane is determined by the balance between surface emissions and photochemical destruction by the hydroxyl radical, the major atmospheric oxidant. Remarkably, this growth rate has decreased markedly since the ...
Paulsen P - - 2006
The microflora was studied in beef stored in stainless steel containers kept under reduced pressure (20 to 30 kPa) in a modified atmosphere (70% N2 + 30% CO2 or pure CO2) at 3 to 4 degrees C and 0 to 1 degrees C at a headspace:meat volume ratio of 2:1. ...
De Blasio Fabio Vittorio - - 2006
Ammonoids are a group of extinct mollusks belonging to the same class of the living genus Nautilus (cephalopoda). In both Nautili and ammonoids, the (usually planospiral) shell is divided into chambers separated by septa that, during their lifetime, are filled with gas at atmospheric pressure. The intersection of septa with ...
Muller Arno - - 2006
OBJECTIVES: To observe the relative role of individual and group-level antimicrobial selective pressure on subsequent methicillin-resistant Staphylococcus aureus (MRSA) isolation in a university hospital. METHODS: For this purpose, 18 596 patients were included in a retrospective statistical analysis, applying multilevel modelling with discrete time intervals at the lowest level. Individual-level ...
Gelfand Robert - - 2006
INTRODUCTION: It was hypothesized that long-duration exposures to toxic levels of hyperoxia would have effects on respiratory control function or activity. METHODS: Ventilatory parameters of human subjects breathing spontaneously at rest were measured before, during, and after hyperoxia in a study of organ systems' tolerance to toxic O2 exposures at ...
Cabigas Bernadette P - - 2006
OBJECTIVE: The relative contributions of the fraction of inspired oxygen (FIO2) and atmospheric pressure (ATM) to cardioprotection are unknown. We determined whether the product of FIO2 x ATM (oxygen partial pressure) controls the extent of hyperoxic+hyperbaric-induced cardioprotection and involves activation of nitric oxide synthase (NOS). METHODS: Adult Sprague Dawley rats ...
Guimarães F A G - - 2006
This study was designed to investigate the feasibility of building a simple and inexpensive device to preserve organs or tissues in hyperbaric and hypothermic conditions. METHODS: The device was built on a 40-cm wide, 28-cm long, and 23-cm deep stainless steel chassis. The pressure vessel was built by a 7.8-cm ...
Ascenzi Daniela - - 2006
Benzene can be efficiently converted into phenol when it is treated by either corona or dielectric barrier discharge (DBD) plasmas operating at atmospheric pressure in air or mixtures of N(2) and O(2). Phenol produced by corona discharge in an atmospheric pressure chemical ionization source (APCI) has been detected as the ...
Visser M J - - 2006
Exposure to endotoxin at sewage treatment plants is associated with an increased prevalence of work-related symptoms in sewage workers. Since cleaning activities are regarded as an important determinant of endotoxin exposure, workers' endotoxin exposure levels during different cleaning activities were compared in an experimental setting. Variables considered were water used ...
Kauppila T J - - 2006
A group of five neurotransmitters with different properties was analyzed using atmospheric pressure photoionization (APPI) and atmospheric pressure chemical ionization-mass spectrometry (APCI-MS). The sensitivity of the techniques for the analytes was tested in six solvents and in positive and negative ion modes. APPI was found to be superior in sensitivity ...
Rostain J C - - 2006
Compressed air or a nitrogen-oxygen mixture produces from 0.3 MPa nitrogen narcosis. The traditional view was that anaesthesia or narcosis occurs when the volume of a hydrophobic site is caused to expand beyond a critical amount by the absorption of molecules of a narcotic gas. The observation of the pressure ...
Boussuges Alain - - 2006
OBJECTIVE: Cardiac changes induced by scuba diving were investigated using Doppler echocardiography. MATERIAL AND METHODS: Ten healthy scuba divers dove to a mean depth of 34.3 +/- 2.7 m of sea water (113 +/- 9 feet) and a mean duration of 25.3 +/- 3.5 min. RESULTS: One hour after the ...
Amérand A - - 2006
In ectotherms as well as in endotherms, the mitochondrial respiratory chain is the major source of reactive oxygen species (ROS) including the highly reactive, hydroxyl radical (OH*). It is known that the different steps involved in ROS production and the antioxidant systems are comparable in ectotherms and endotherms. But regulatory ...
Talpalar A E - - 2006
Exposure to high pressures (HP) has been associated with the development of the high pressure neurological syndrome (HPNS) in deep-divers and experimental animals. In contrast, many diving mammals are naturally able to withstand very high pressures. Although at a certain pressure range humans are also able to perform to some ...
Loozen Els - - 2006
In mixtures of PVME and water, the influence of pressure on the LCST miscibility gap is determined covering the whole composition range and pressures from atmospheric pressure up to 900 MPa. The cloud point curve at atmospheric pressure has the characteristic bimodal shape in agreement with literature data. Upon increasing ...
Nakamoto, T.
Three groups of young rats (age 22 days) were exposed intermittently (49 times), over a period of 44 days, group 1 to O2 at atmospheric pressure (OAP), group 2 to O2 at high pressure (OHP) (60 psig) and the third to air at atmospheric pressure (AAP) as controls. The average ...
Trigano Alexandre - - 2006
OBJECTIVES: The aim of this study was to test a variety of currently available activity-based rate-adaptive pacemakers under hyperbaric conditions. BACKGROUND: Sports divers with pacemakers can dive under certain circumstances. The rate response of activity-sensing pacing under hyperbaric conditions has rarely been evaluated. MATERIALS AND METHODS: We manufactured a miniaturized ...
Korhonen Ilkka - - 2006
OBJECTIVES: Comparison of the effects of different types of cold exposure on blood pressure and heart rate. STUDY DESIGN: Controlled laboratory study. METHODS: Twenty healthy men were exposed to three different types of cold exposure: cold pressor tests for hands and feet, and a 2-h cold air exposure at an ...
Olsovcová Veronika - - 2006
The activity of radioactive pharmaceuticals administered to patients in nuclear medicine is usually determined using well-type high-pressure ionization chambers. For the Bqmeter chamber (Consortium BQM, Czech Republic) a Monte Carlo model was created using the MCNP4C2 code. Basic chamber characteristics for two sample containers of various geometry (a vial and ...
Enami Shinichi - - 2006
Cavity ring-down spectroscopy was used to study the reaction of ClOO with NO in 50-150 Torr total pressure of O2/N2 diluent at 205-243 K. A value of k(ClOO+NO) = (4.5 +/- 0.9) x 10(-11) cm3 molecule(-1) s(-1) at 213 K was determined (quoted uncertainties are two standard deviations). The yield ...
Del Seppia Cristina - - 2006
There is evidence suggesting that exposure to an abnormal magnetic environment may produce psychophysiological effects related to abnormalities in responses to stress. This may be of relevance for space medicine where astronauts are exposed to a magnetic field different from that exerted by the Earth. Aim of this study was ...
Koehle M S - - 2006
The purpose of this study was to assess the contribution of SCUBA to the pulmonary effects of diving to 4.5 meters depth in healthy subjects using a randomized crossover control condition. Ten healthy divers performed two 60-minute 'dives' using SCUBA in a swimming pool. The non-immersed 1 ATA SCUBA control ...
Arakawa Shizuka - - 2006
Deep-sea sediment samples were collected at a depth of 3,064 m in the Japan Sea. Microorganisms in the sediment sample were cultivated under several pressure conditions, and the high-pressure adapted microbes were isolated. Two of the isolates exhibited piezophilic growth profiles. This is the first report to show the presence ...
Hammerschmidt Chad R - - 2006
The fate of atmospherically deposited and environmentally active Hg is uncertain in the Arctic, and of greatest toxicological concern is the transformation to monometh-ylmercury (MMHg). Lake/watershed mass balances were developed to examine MMHg cycling in four northern Alaska lakes near the ecological research station at Toolik Lake (68 degrees 38' ...
Malara P - - 2006
High-sensitivity spectroscopy of methane around 3 microm was carried out by means of a 5.5-mW cw difference-frequency generator in conjunction with a high finesse cavity in off-axis alignment. By cavity-output integration a minimum detectable absorption coefficient of 5.7*10-9 cm-1Hz-1/2 was achieved, which compares well with results already reported in the ...
Walker K J - - 2006
The performance of a proprietary dry suction pleural drainage unit was measured under hyperbaric oxygenation conditions. The test pleural drainage unit was connected to pressure gauges that allowed the pressures created in the suction and collection chambers to be measured as well as the pleural drainage catheter pressures under varied ...
Siemons Nikolai - - 2006
Carbon dioxide injection into coal layers serves the dual purpose to enhance coal bed methane production (ECBM) and to store CO2. The efficiency of this process is expected to be much higher if water is the non-wetting phase in the coal-water-gas system. Therefore, contact angles in the coal-water-CO2 system have ...
Villeneuve P J - - 2006
BACKGROUND: Self-reported surveys have indicated that weather can trigger migraine headaches. However, to date, we know of no previous study that has examined the relationship between weather and emergency room (ER) visits for this condition. OBJECTIVE: To examine associations between ER visits for migraines and selected meteorological conditions within the ...
Mahon Richard T - - 2006
INTRODUCTION: Disabled submarine survivors could achieve inert gas tissue saturation likely to cause severe decompression sickness (DCS) on surfacing. This risk increases with time and depth of exposure. Methods to reduce DCS risk and severity are needed specifically for such an operational scenario. METHODS: Yorkshire swine (16.2-26.6 kg) fitted with ...
Hiraoka Kenzo - - 2006
A study has been made of the atmospheric-pressure Penning ionization (APPeI) of aliphatic hydrocarbons (pentane, hexane, heptane, and octane) with long-lived rare gas atoms (Rg*). The metastable rare gas atoms (He*, Ne*, Ar* and Kr*) were generated by the negative-mode corona discharge of atmospheric-pressure rare gases. In the Rg*APPeI mass ...
Schwartz H - - 2006
Transverse furrows, or Beau's lines, were noted in the fingernails of all 6 divers following a deep saturation dive to apressure equal to 1100 feet (335 meters) ofsea water (3,370 kPa), and in 2 of6 divers following a similar dive to 1000 feet (305 meters) of sea water (3,164 kPa). ...
Li Jingsong - - 2006
An inexpensive resonant photoacoustic spectrometer based on a low-power distributed feedback diode laser and wavelength modulation spectroscopy is developed. This sensor has been applied to the detection of acetylene (C2H2) using a properly designed photoacoustic cell operating on its second longitudinal mode. The minimum detectable limit of about 10 parts-per-million ...
Boone Chris D - - 2005
SCISAT-1, also known as the Atmospheric Chemistry Experiment, is a satellite mission for remote sensing of the Earth's atmosphere, launched on 12 August 2003. The primary instrument on the satellite is a 0.02 cm(-1) resolution Fourier-transform spectrometer operating in the mid-IR (750-4400 cm(-1)). We describe the approach developed for the ...
Zhang Jiangyue - - 2005
To study ballistic brain injury biomechanics, two common civilian full metal jacket handgun projectiles (25-caliber and 9-mm) were discharged into a transparent brain simulant (Sylgard gel). Five pressure transducers were placed at the entry (two), exit (two) and center (one) of the simulant. High-speed digital video photography (20,000 frames/second) was ...
Tabrizchi Mahmoud - - 2006
This paper explains the effect of pressure on separation factor, resolving power (defined based on a single peak), and resolution (defined based on two adjacent peaks) in ion mobility spectrometry. IMS spectra were recorded at various pressures ranging from 39 hPa (29Torr) up to atmospheric pressure and various ion gates ...
Aguedo M - - 2005
Yarrowia lipolytica converts methyl ricinoleate to gamma-decalactone, a high-value fruity aroma compound. The highest amount of 3-hydroxy-gamma-decalactone produced by the yeast (263 mg l(-1)) occurred by increasing the k(L)a up to 120 h(-1) at atmospheric pressure; above it, its concentration decreased, suggesting a predominance of the activity of 3-hydroxyacyl-CoA dehydrogenase. ...
Suzuki Yasumasa - - 2005
Apparatus comprising a scanning tunneling microscopy (STM) and an atomic force microscopy (AFM) has been developed for use under supra-atmospheres. Observations of highly oriented pyrolytic graphite (HOPG) were carried out by STM and contact AFM operating in air and various gas atmospheres (hydrogen, helium, neon and argon) under pressures up ...
Zacharias Jaime - - 2005
PURPOSE: To propose an alternative method to characterize postocclusion surge using a collapsible artificial anterior chamber to replace the currently used rigid anterior chamber model. SETTING: Fundaci?n Oftamol?gica Los Andes, Santiago, Chile. METHODS: The distal end of a phacoemulsification handpiece was placed inside a compliant artificial anterior chamber. Digital recordings ...
Harkin D W - - 2005
Seasonal and circadian variation in the incidence of ruptured abdominal aortic aneurysm (RAAA) has been reported. We explored the role of atmospheric pressure changes on rupture incidence and its relationship to cardiovascular risk factors. During a three year-period, 1st April 1998 and 31st March 2001, data was prospectively acquired on ...
Nicholson Wayne L - - 2005
Bacterial endospores in the genus Bacillus are considered good models for studying interplanetary transfer of microbes by natural or human processes. Although spore survival during transfer itself has been the subject of considerable study, the fate of spores in extraterrestrial environments has received less attention. In this report we subjected ...
Ohura Takeshi - - 2005
We measured exposure to fine particles (PM2.5) and polycyclic aromatic hydrocarbons (PAHs), including carcinogenic PAHs, in multiple locations for a diverse population of participants who resided in Shizuoka, Japan. In summer and winter 2002 we surveyed personal concentrations, those of four primary indoor microenvironments-living room, bedroom, kitchen (summer only), and ...
Knower Stockard T - - 2005
In order to determine the rate and magnitude of respiratory O2 depletion during dives of emperor penguins (Aptenodytes forsteri), air sac O2 partial pressure (PO2) was recorded in 73 dives of four birds at an isolated dive hole. These results were evaluated with respect to hypoxic tolerance, the aerobic dive ...
Oter Sukru - - 2005
OBJECTIVES: The oxygen toxicity risk of hyperbaric oxygen (HBO) treatment has long been of interest. However, there are no comprehensive articles describing the relationship between HBO protocols and oxidative parameters used clinically. The purpose of this study was to determine the effects of various HBO pressure modalities on the oxidative ...
Houck Philip D - - 2005
Previous studies have demonstrated variation in vascular events with respect to season and time of day. Changes in barometric pressure display daily and seasonal variations and could modulate the occurrence of vascular events. The objective of this study was to determine whether a relation exists between changes in barometric pressure ...
Arao Toshiaki - - 2005
Microcalorimetry is a useful tool for monitoring the growth behavior of microorganisms. In this study, microcalorimetry was used to investigate the effects of nitrogen, air, oxygen, nitrous oxide, argon, and krypton at high pressure on the growth of the yeast Saccharomyces cerevisiae. Growth thermograms (metabolic heat vs. incubation time) were ...
Brubakk A O - - 2005
During and after decompression from dives, gas bubbles are regularly observed in the right ventricular outflow tract. A number of studies have documented that these bubbles can lead to endothelial dysfunction in the pulmonary artery but no data exist on the effect of diving on arterial endothelial function. The present ...
Koyama Sumihiro - - 2005
We report successful larval hatching of deep-sea shrimp after decompression to atmospheric pressure. Three specimens of deep-sea shrimp were collected from an ocean depth of 1157 m at cold-seep sites off Hatsushima Island in Sagami Bay, Japan, using a pressure-stat aquarium system. Phylogenetic analysis of Alvinocaris sp. based on cytochrome ...
Mbata George N - - 2005
Previous studies have shown that low pressure creates a low oxygen controlled atmosphere that can kill stored-product insects. The current study was conducted to determine the mortality of life stages of the cowpea weevil, Callosbruchus maculatus (F.) (Coleoptera: Bruchidae), exposed to different low pressures and temperatures for various exposure periods. ...
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