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Results 201 - 250 of 1046
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Chuang Ming-Tung - - 2008
The aerosol in the Taipei basin is difficult to transport outward under specific weather patterns owing to complex terrain blocking. In this study, seven weather patterns are identified from synoptic weather maps for aerosol events, which occurred from March 2002 to February 2005. Among the identified weather patterns, High Pressure ...
Gao Liang - - 2008
The performance of mass spectrometers with limited pumping capacity is shown to be improved through use of a discontinuous atmospheric pressure interface (DAPI). A proof-of-concept DAPI interface was designed and characterized using a miniature rectilinear ion trap mass spectrometer. The interface consists of a simple capillary directly connecting the atmospheric ...
Jones David F - - 2008
The Idaho Department of Environmental Quality INL Oversight Program (DEQ-INL) operates an environmental gamma radiation detection network consisting of a series of high-pressure ion chambers to provide real-time ambient radiation measurements and a series of passive environmental electret ion chambers to increase coverage area and measure cumulative dose over a ...
Meir Jessica U - - 2008
To investigate the diving heart rate (f(H)) response of the emperor penguin (Aptenodytes forsteri), the consummate avian diver, birds diving at an isolated dive hole in McMurdo Sound, Antarctica were outfitted with digital electrocardiogram recorders, two-axis accelerometers and time depth recorders (TDRs). In contrast to any other freely diving bird, ...
Bedi Abhayjit - - 2008
STATEMENT OF PROBLEM: Surface roughness and irregularities can affect the fit of a restoration. It is unknown whether different investment techniques have an effect on surface roughness and irregularities of gold palladium alloy castings. PURPOSE: The purpose of this study was to evaluate the surface roughness and irregularities of gold ...
Walsh John E - - 2008
The climate of the Arctic marine environment is characterized by strong seasonality in the incoming solar radiation and by tremendous spatial variations arising from a variety of surface types, including open ocean, sea ice, large islands, and proximity to major landmasses. Interannual and decadal-scale variations are prominent features of Arctic ...
Marabotti C - - 2008
Breath-hold diving induces, in marine mammals, a reduction of cardiac output due to a decrease of both heart rate and stroke volume. Cardiovascular changes in humans during breath-hold diving are only partially known due to the technical difficulty of studying fully immersed subjects. Recently, a submersible echocardiograph has been developed, ...
Shykoff B E - - 2008
To detect cumulative effects of and check required recovery times between underwater exposures to 130-140 kPa oxygen, we assessed pulmonary oxygen toxicity after resting dives for four and six hours on two, five, and six or ten days, and three hours twice on each of two days. Despite a slight ...
Lindholm Peter - - 2008
To simulate pressure effects and experience thoracic compression while breath-hold diving in a relatively safe environment, competitive breath-hold divers exhale to residual volume before diving in a swimming pool, thus compressing the chest even at depth of only 3-6 m. The study was undertaken to investigate whether such diving could ...
Nakaguchi Hiroshi - - 2008
We analyzed the relationship between the incidence of spontaneous intracerebral hemorrhage (ICH) and various meteorological data (daily atmospheric air pressure, air temperature, precipitation, humidity, presence of typhoons, occurrence of the rainy season, wind velocity, and wind direction) for patients at Teraoka Memorial Hospital in Shin-ichi Town, Japan, from January 1, ...
Yoshida Yu - - 2008
The inert fluid perfluorocarbon (PFC) has been used since about 1960 in liquid respiration and artificial blood for mammals. PFC has been used to successfully resuscitate tardigrades that had been dried and exposed to a high barometric pressure of 6000 atmospheres. Next, scientists attempted to experimentally preserve organs that had ...
Guo Changjuan - - 2008
We describe a homemade high-resolution orthogonal-injection time-of-flight (O-TOF) mass spectrometer combing a heated capillary inlet. The O-TOF uses a heated capillary tube combined with a radio-frequency only quadrupole (rf-only quadrupole) as an interface to help the ion transmission from the atmospheric pressure to the low-pressure regions. The principle, configuration of ...
Sadé Jacob - - 2008
CONCLUSIONS: King penguins have a venous structure in the form of a corpus cavernosum (CC) in their middle ear (ME) submucosa. The CC may be viewed as a special organelle that can change ME volume for pressure equilibration during deep-sea diving it is a pressure regulating organelle (PRO). A similar ...
Bowlin Melissa S - - 2008
Migratory bird, bat and insect species tend to have more pointed wings than non-migrants. Pointed wings and low wingloading, or body mass divided by wing area, are thought to reduce energy consumption during long-distance flight, but these hypotheses have never been directly tested. Furthermore, it is not clear how the ...
Lopes M - - 2008
AIMS: To study the cellular growth and morphology of Yarrowia lipolytica W29 and its lipase and protease production under increased air pressures. METHODS AND RESULTS: Batch cultures of the yeast were conducted in a pressurized bioreactor at 4 and 8 bar of air pressure and the cellular behaviour was compared ...
Gole Y - - 2009
OBJECTIVE: Several stressors such as cold water immersion, hyperoxic exposure and decompression-induced circulating bubbles can alter arterial circulation after a dive. The aim of this study was to investigate the arterial modifications induced by a specific diving training including repeated hyperbaric exposures and physical training. METHOD: Arterial pressure measurement and ...
Koyama Sumihiro - - 2007
Establishing tissue cultures derived from deep-sea multicellular organisms has been extremely difficult because of the serious damage they sustain upon decompression and exposure to the high temperature of surface seawater. We developed a novel pressure-stat aquarium system for the study of living deep-sea multicellular organisms under pressure. Using this system, ...
Guillemette Magella - - 2007
Although the replacement of feathers apparently represents the major event of somatic production in the annual cycle of wild birds, knowledge about the energetics of molt has always been hampered by logistical and technical difficulties, which are exacerbated by the fact that birds are able to compensate behaviorally to buffer ...
Weaver Lindell K - - 2007
BACKGROUND: Most hyperbaric medicine centers do not monitor arterial oxygen (P(aO(2))) and carbon dioxide (P(aCO(2))) tensions during hyperbaric oxygen, but many can transcutaneously monitor oxygen (P(tcO(2))) and carbon dioxide (P(tcCO(2))). METHODS: We compared P(tcO(2)) and P(tcCO(2)) measurements to simultaneous P(aO(2)) and P(aCO(2)) measurements in 10 healthy volunteers to determine if ...
Kuehn Michael - - 2008
The present study aimed at investigating the question whether olfactory function changes in relation to barometric pressure and humidity. Using climate chambers, odor threshold and discrimination for butanol were tested in 75 healthy volunteers under hypobaric and hyperbaric, and different humidity conditions. Among other effects, olfactory sensitivity at threshold level, ...
Taraldsøy T - - 2007
The objective of this study was to evaluate exhaled nitric oxide concentration (FENO) and exhaled breath condensate (EBC) pH and H2O2 as biochemical markers of pulmonary oxygen toxicity in association with hyperbaric oxygen (HBO2) therapy. FENO, EBC pH and H2O2 were measured during the course of a 4 week HBO, ...
Barker Anthony T - - 2007
An acute rise in blood pressure has been reported in normal volunteers during exposure to signals from a mobile phone handset. To investigate this finding further we carried out a double blind study in 120 healthy volunteers (43 men, 77 women) in whom we measured mean arterial pressure (MAP) during ...
Park Dal Jae - - 2008
Experimental investigations were performed to examine the effects of flame interactions with different multiple obstacles within chambers of different L/D ratios. The basic chamber consists of a rectangular box, 200 mm in height, with a 700 mm x 700 mm cross-section and a large top-venting area of 700 mm x ...
Kubota Yoichi - - 2007
Materials emitting light in the deep ultraviolet region around 200 nanometers are essential in a wide-range of applications, such as information storage technology, environmental protection, and medical treatment. Hexagonal boron nitride (hBN), which was recently found to be a promising deep ultraviolet light emitter, has traditionally been synthesized under high ...
Moore George E - - 2008
Gastric dilatation-volvulus (GDV) is a life-threatening condition in dogs and other species in which the stomach dilates and rotates on itself. The etiology of the disease is multi-factorial, but explicit precipitating causes are unknown. This study sought to determine if there was a significant association between changes in hourly-measured temperature ...
Kelly Paul T - - 2007
BACKGROUND AND OBJECTIVES: In the low pressure environment of commercial aircraft, hypoxaemia may be common and accentuated in patients with lung or heart disease. Regulations specify a cabin pressure not lower than 750 hPa but it is not known whether this standard is met. This knowledge is important in determining ...
Hopson A S M - - 2007
Haemodynamic instability is a recognised phenomenon in critically ill patients undergoing hyperbaric therapy. Instability may result from the effects of ambient pressure on the cardiovascular system, devices involved in infusion of drugs and fluids, or a combination of the two. The effect of hyperbaric pressure on air-containing spaces in syringes ...
Boussuges Alain - - 2007
BACKGROUND: Oxygen divers undergo environmental stressors such as immersion, ventilation with scuba, cold exposure, and increased ambient pressure. All of these stressors may be responsible for acute hemodynamic modifications. We hypothesized that repeated hyperbaric hyperoxia exposure induces long-term cardiovascular modifications. METHODS: A Doppler echocardiography was conducted on 20 military oxygen ...
Hart G B - - 2007
OBJECTIVES: The purpose of this study is to ascertain if gender differences exist in human skeletal muscle (MM) and subcutaneous (SC) tissue gases using monoplace and multiplace hyperbaric oxygen (HBO2) treatment protocols. METHODS: Gas tensions in resting MM and SQ tissues were recorded at 4-minute intervals using two protocols: The ...
Sakai Hidetsugu - - 2007
Mechanical stress by pressure overload due to hypertension or valvular heart disease such as aortic valve stenosis induces cardiac hypertrophy. It has been well established that the mechanical stretch of cardiac myocytes in vitro induces hypertrophic responses such as the expression of immediate early response genes including c-fos. However, it ...
Davis Lee A J - - 2007
The performance of capacitive micromachined ultrasonic transducers (cMUTs) was investigated at low pressures in various gases such as air, carbon dioxide, and helium. The aim was to replicate the pressure conditions likely to meet on the surface of other planets such as Mars, where ultrasonic wind velocity measurements might be ...
Doherty Michael J - - 2007
OBJECTIVE: To demonstrate that seizure frequency in patients undergoing video EEG telemetry does not correlate with atmospheric pressure (AP) changes. METHOD: Historical automated AP data from weather stations in the Seattle Metropolitan area were correlated to seizure frequency and type in consecutive patients undergoing video EEG telemetry at our institution ...
Enami Shinichi - - 2007
The rate constant of the reaction of BrO with CH(3)O(2) was determined to be k1 = (6.2 +/- 2.5) x 10(-12) cm3 molecule(-1) s(-1) at 298 K and 100-200 Torr of O2 diluent. Quoted uncertainty was two standard deviations. No significant pressure dependence of the rate constants was observed at ...
Mor Amir - - 2007
Pressure above 1.1 MPa induces in mammals and humans the high pressure neurological syndrome (HPNS). HPNS is characterized by cognitive and motor decrements associated with sleep disorders, EEG changes, tremor, and convulsions that ultimately may lead to death. Previous theories proposed that augmented response of the glutamatergic N-methyl-D-aspartate receptor (NMDAR) ...
Lievonen J - - 2007
A commercial atomic force microscope (AFM), originally designed for operation in ambient conditions, was placed inside a compact aluminum chamber, which can be pumped down to high vacuum levels or filled with a desired gaseous atmosphere, including humidity, up to normal pressure. The design of this environmental AFM is such ...
Choi Ji-Ho - - 2007
Many studies have shown a consistent association between ambient air pollution and an increase in death due to cardiovascular causes. An increase in blood pressure is a common risk factor for a variety of cardiovascular diseases. However, the association between air pollution and blood pressure has not been evaluated extensively. ...
Alifano Marco - - 2007
BACKGROUND: Idiopathic spontaneous pneumothorax (ISP) results from rupture of blebs, bullas, or diseased alveolar walls. Initiating mechanisms may relate to increased transpulmonary pressure. The possible impact of changes in atmospheric pressure (Patm) on the occurrence of ISP remains uncertain. METHODS: We studied the relationship between the occurrence of ISP and ...
Setzer Matthias - - 2007
BACKGROUND: The purpose of this study was to examine a possible association between standard meteorological variables and their changes and the occurrence and clinical features of SAH. METHODS: Univariate association between the clinical/radiographic variables of patients with SAH and standard meteorological variables was evaluated. Next, a multivariate analysis was performed ...
Rodgers Sarah E - - 2007
The biological processes affecting Ixodes scapularis Say survival are complex. Understanding these processes will be beneficial for predicting tick distribution and population dynamics. This research shows that the duration for which nymphal ticks are exposed to drying air is an important factor for their survival. Experimental analysis of variance results ...
Goplen F K - - 2007
INTRODUCTION: There is evidence that increased ambient pressure causes an increase in postural sway. This article documents postural sway at pressures not previously studied and discusses possible mechanisms. METHODS: Eight subjects participated in a dry chamber dive to 240 msw (2.5 MPa) saturation pressure. Two subjects were excluded due to ...
Eralp Levant - - 2007
Investigators in the present study explored the effects of hyperbaric oxygen (HBO) therapy on distraction osteogenesis in a rabbit limb-lengthening model. HBO treatment was provided to participants in a small animal pressure chamber once a day during the latent period of distraction osteogenesis at 2.5 absolute atmospheres of pressure. Bone ...
Ajcharanukul Orapin - - 2007
OBJECTIVE: To determine the effect of applying 500 mmol/l KCl at a pressure of 150 mm Hg above atmospheric to exposed dentine on pain sensation evoked by probing and air blast stimuli in human subjects. DESIGN: The experiments were carried out on 14 pairs of premolars in 14 human subjects ...
Zielczynski M - - 2007
A new method is proposed for the determination of dose components in mixed radiation fields (gamma + neutrons) using a recombination chamber. The method involves the determination of the ratio of ionisation currents measured at two different voltages applied to the chamber without the need of determining the saturation current, ...
Radziwon P - - 2007
BACKGROUND: There are a number of reported cases of decompression sickness (DCS) with haemorrhages. These cases have not been sufficiently investigated and thus bleeding complications could not be directly correlated to the enhanced fibrinolysis. OBJECTIVES: The effect of hyperbaric exposition and decompression on the main components of fibrinolytic system has ...
Zimmermann D - - 2007
The water supply to leaves of 25 to 60 m tall trees (including high-salinity-tolerant ones) was studied. The filling status of the xylem vessels was determined by xylem sap extraction (using jet-discharge, gravity-discharge, and centrifugation) and by (1)H nuclear magnetic resonance imaging of wood pieces. Simultaneously, pressure bomb experiments were ...
Grassi Paolo - - 2007
INTRODUCTION: B-type natriuretic peptide (BNP) is a cardiac hormone used as a marker of cardiac dysfunction with diuretic and vasodilating properties secreted by the ventricles in response to wall stress. Hyperbaric oxygen (HBO) exposure is known to induce hemodynamic effects in humans which can be complicated by acute pulmonary edema. ...
Mor Amir - - 2006
In humans, hyperbaric pressure induces the high-pressure neurological syndrome (HPNS). HPNS is characterized by tremor, sleep disorders, electroencephalographic changes, and impairment of cognitive and motor performances. In animals, higher pressures result in convulsions and death. An increased N-methyl-d-aspartate receptor (NMDAR) response has been implicated with HPNS. We studied high-pressure effects ...
Obad Ante - - 2007
Diving-induced acute alterations in cardiovascular function such as arterial endothelial dysfunction, increased pulmonary artery pressure (PAP) and reduced heart function have been recently reported. We tested the effects of acute antioxidants on arterial endothelial function, PAP and heart function before and after a field dive. Vitamins C (2 g) and ...
Nazarov Erkinjon G - - 2006
A microfabricated planar differential ion mobility spectrometer operating from 0.4 to 1.55 atm in a supporting atmosphere of purified air was used to characterize the effects of pressure and electric field strength on compensation voltage, ion transmission, peak width, and peak intensity in differential mobility spectra. Peak positions, in compensation ...
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 ...
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