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Dodd I C - - 2002
The role of shoot water status in mediating the decline in leaf elongation rate of nitrogen (N)-deprived barley plants was assessed. Plants were grown at two levels of N supply, with or without the application of pneumatic pressure to the roots. Applying enough pressure (balancing pressure) to keep xylem sap ...
Broekaert J A C - - 2002
Miniaturized microwave, high-frequency, and dc-powered microplasmas are discussed, with emphasis on the state-of-the-art and development trends. Specific atomic emission sources discussed include the microstrip microwave plasma operated in argon and helium at ca 10-30 W and below 1 L min(-1) gas at atmospheric pressure, the capacitively coupled microplasma, operated at ...
Zimmer J L - - 2002
The increased use of UV radiation as a drinking water treatment technology has instigated studies of the repair potential of microorganisms following treatment. This study challenged the repair potential of an optimally grown nonpathogenic laboratory strain of Escherichia coli after UV radiation from low- and medium-pressure lamps. Samples were irradiated ...
Nagashima Hidetoshi - - 2002
Sleep patterns during saturation dives equivalent to a 30-m depth (pressurized condition) and habitation in a confined environment at 1 atm absolute pressure (non-pressurized condition) were studied to determine the effects of environmental pressure. Eight inexperienced divers experienced the pressurized condition of the saturation dives, and nine healthy subjects experienced ...
Muhonen Arja - - 2002
The purpose of the study was to evaluate the effects of irradiation and hyperbaric oxygenation (HBO) on osteoblastic activity of the temporomandibular joint (TMJ) region during mandibular distraction osteogenesis. Unilateral distraction was performed on 19 rabbits, which were divided into five groups. One group served as a control group, while ...
Danielides V - - 2002
This retrospective study aims to search out the influence of temperature, atmospheric pressure and humidity on the frequency of epistaxis. The study includes 701 patients who have suffered from epistaxis and have been treated in the ENT department of the University of Ioannina Hospital, during the years 1995 and 1996. ...
Park Chan Beum - - 2002
The effect of decompression on the structure of Methanococcus jannaschii, an extremely thermophilic deep-sea methanogen, was studied in a novel high-pressure, high-temperature bioreactor. The cell envelope of M. jannaschii appeared to rupture upon rapid decompression (ca. 1 s) from 260 atm of hyperbaric pressure. When decompression from 260 atm was ...
Marković Dubravko - - 2002
This paper describes the treatment of a severe case of acute mountain sickness with a portable hyperbaric chamber. A 37-year old climber was treated for acute high altitude pulmonary oedema, which developed on the North Col of Mount Everest, at an altitude of 7,060 m. The treatment in the portable ...
Kertesz Vilmos - - 2002
Reduction of the oligomers formed from on-line electropolymerization of aniline, the compound N-phenyl-1,4-phenylenediimine, and the thiazine dye thionin was observed in both an atmospheric pressure chemical ionization and an atmospheric pressure photoionization source. The reduction, which alters the mass of these analytes by 2 Da, was shown to occur by ...
Sicko Zdzisław - - 2002
The basic problem in decompression is the limit of maximum tolerable change of pressure after diving. Due to the number of parameters involved in decompression models (bottom time, ambient pressure, exposition profile, content of breathing mixtures, properties of inert gases) the number of possible solutions is theoretically unlimited. Since the ...
Weiner Randy - - 2002
Those individuals interested in diving and flying are often more susceptible to a condition known as barodontalgia: tooth sensitivity or pain caused by a change in pressure. More specifically, the discomfort is caused by a change in ambient pressure, which affects liquids and gases within the body. Diagnosis is based ...
Sakamoto K - - 2002
The effect of pressured environment from 1 to 24 ATA (Atmosphere Absolute) on total power spectrum (TP) of physiological tremor, whose value was the sum of power spectra for frequency range in 0.5-50 Hz, was investigated. The main effects obtained were as follows. (1) In the case of 3 ATA, ...
Dempster William F - - 2002
Atmospheric leakage from a Mars base would create a demand for continuous or periodic replenishment, which would in turn require extraction or mining for oxygen and other gases from local resources and attendant equipment and energy requirements for such operations. It therefore becomes a high priority to minimize leakage. This ...
Coon Joshua J - - 2002
We have designed and constructed an atmospheric pressure laser desorption/chemical ionization (AP-LD/CI) source that utilizes a laser pulse to desorb intact neutral molecules, followed by chemical ionization via reagent ions produced by a corona discharge. This source employs a heated capillary atmospheric pressure inlet coupled to a quadrupole ion trap ...
Neeper Donald A - - 2002
This paper documents a technique for investigating one-dimensional airflow in the vadose zone. Variations in pore gas pressures resulting from barometric cycles were measured at depths as great as 180 m in several gas monitoring wells. The data were transformed to the frequency domain, enabling comparison with closed-form analytic expressions ...
Dubin Marc G - - 2002
OBJECTIVE: To examine the effects of tobacco smoke exposure on eustachian tube (ET) function. STUDY DESIGN: ET pressures of Sprague Dawley Rats (n = 16) were measured after 1, 7, and 15 exposures and in control animals. Passive opening pressure, passive closing pressure, active clearance of positive pressure, and active ...
de Diego J I - - 2002
To assess the possible influence of atmospheric factors on the incidence of Bell's palsy, a retrospective case review of patients seen between 1 January 1992 and 30 June 1996, was designed. The population included all Bell's palsy patients in whom the exact date of onset of paralysis (day, month, year) ...
Lemaître F - - 2002
Long term effects on respiratory function have been found in air divers and have indicated the development of small-airway disease. These effects have been attributed to oxygen toxicity or to venous gas micro emboli (VGM). The airway obstructions observed in air divers raise fundamental questions about whether these alterations exist ...
Dillard T A - - 2001
Millions of people engage in occupational or leisure activities at high altitude or at variable depths below sea level. This article presents an overview of the utility of pulmonary function testing in evaluating complications and other consequences of exposure to high and low pressure environments. The authors review recent literature ...
Boggs D F - - 2001
Air-sac pressures have been reported to oscillate with wing beat in flying magpies and with foot paddling in diving ducks. We sought to determine the impact on air-sac pressure of wing beats during swimming and of the step cycle during walking in little penguins (Eudyptula minor). Fluctuations averaged 0.16+/-0.06 kPa ...
McGregor G R - - 2001
Winter ischaemic heart disease (IHD) mortality events (ME) were identified in order to establish their degree of meteorological sensitivity. Sensitivity was evaluated using regression of surface meteorological and large-scale atmospheric circulation variables on daily mortality for each mortality event. Critical meteorological variables affecting IHD mortality appear to be local surface ...
Buxton N - - 2001
OBJECT: The purpose of this study was to evaluate the relationship between atmospheric pressure and subarachnoid hemorrhage (SAH) in a region in the English Midlands. METHODS: All patients with angiographically proven SAH for the calendar year 1998 were analyzed. A geographical allocation was made based on the patients' origin within ...
Davies D L - - 2001
BACKGROUND: This article uses a direct ethanol antagonist, increased atmospheric pressure, to further test the causative link between ethanol potentiation of gamma-aminobutyric acid (GABA) type A receptor function and ethanol's behavioral effects. This was done by determining whether initial biochemical findings in long-sleep (LS) mice extended to other genotypes and ...
Castellini M A - - 2001
Marine mammals are known to dive up to 2000 m and, therefore, tolerate as much as 200 atm. of hydrostatic pressure. To examine possible metabolic adaptations to these elevated pressures, fresh blood samples from marine and terrestrial mammals were incubated for 2 h at 37 degrees C under 136 atm ...
Campbell M J - - 2001
We investigated daily deaths from sudden infant death syndrome (SIDS) in Cook County, Chicago, from 1 January 1986 to 31 December 1990. The daily SIDS rate was 0.54 deaths/day. Mean daily atmospheric pressure ranged from 952 to 1007 mb. We found a weak link with barometric pressure, whereby an increase ...
Davis R W - - 2001
We attached a video system and data recorder to a northern elephant seal to track its three-dimensional movements and observe propulsive strokes of the hind flippers. During 6 h of recording, the seal made 20 dives and spent 90% of the time submerged. Average dive duration, maximum depth and swimming ...
Tetzlaff K - - 2001
This study evaluated the subacute respiratory effects of diving, to try to separate the effects of ambient temperature from those of depth. In the first experiment 10 healthy men made a compressed-air dive to 50 m that exposed them to cold. They were compared with 10 matched control subjects who ...
Tretyakov M. Yu. - - 2001
For the first time the 118-GHz line of the oxygen molecule was investigated in the laboratory under a real atmosphere. The experiment was carried out by modern resonator spectroscopy methods on the laboratory air at atmospheric pressure. The shape of the line under the real atmosphere was found to fit ...
Schwerzmann M - - 2001
Scuba diving has become a popular leisure time activity with distinct risks to health owing to its physical characteristics. Knowledge of the behaviour of any mixture of breathable gases under increased ambient pressure is crucial for safe diving and gives clues as to the pathophysiology of compression or decompression related ...
Shoemaker R W - - 2001
Over half a century ago, when I took Beginning Physics at university, I was bothered by the anomaly that normal air pressure (which is arbitrary anyhow) was taken to be 1.013250 bar instead of a sensible 1.000000 bar. My professor could not explain why, nor could any of the many ...
Sébert P - - 2001
In order to elucidate the difference between pressure resistance in trout (Onchorhyncus mykiss) and eel (Anguilla anguilla), oxygen consumption of red muscle permeabilised cells and mitochondria were measured at 101 ATA hydrostatic pressure per se. Such an experiment involved the setting up of a special system allowing measurements under high ...
Iizuka K - - 2001
Although the types of pathophysiological stimulation that initiate an overexpression of OPN have yet to be determined, we hypothesized that mechanical stress is one of the candidates which initiates OPN expression in vascular smooth muscle cells. Cell proliferation assay indicated that a pure atmospheric pressure of 160 mmHg activated cell ...
Kato C - - 2001
The genus Shewanella is one of the typical deep-sea bacterial genera. Two isolated deep-sea Shewanella species, Shewanella benthica and Shewanella violacea, were found to be able to grow better under high hydrostatic pressure conditions than at atmospheric pressure. These species are not only piezophilic (barophilic), but also psychrophilic. Many psychrophilic ...
Wang G X. - - 2001
Whether stomata oscillations induced by atmospheric drought stress are hydropassive or metabolic energy-dependent and the thresholds of some effective factors were studied in Glycyrrhiza inflata. The metabolic inhibitors NaN(3) and carbonyl cyanide-m-phenyl-hydrazone inhibited the respiration. However they could not significantly change the intensity (amplitude/average) of the stomata oscillation. The leaf ...
Arkebauer T J - - 2001
Emergent aquatic macrophytes in vegetated wetlands provide routes for methane (CH(4)) transport from sites of production in oxygen-poor sediments, where CH(4) concentrations are relatively high, to the atmosphere, which typically has much lower CH(4) concentrations. Transport can occur through aerenchymatous tissue via simple diffusion. Recently, the importance of convective throughflow ...
Stumm G - - 2001
The high pressure neurological syndrome (HPNS), a neurological condition during elevated pressure especially in deep diving, has been simulated with experimental animals. Rats were subjected to 61 bars with slow pressure increase and one or two hours constant high pressure; subsequently the pressure was released to sea level within 20 ...
Ferretti G - - 2001
In this paper, the respiratory, circulatory and metabolic adjustments to human extreme breath-hold diving are reviewed. A survey of the literature reveals that in extreme divers, adaptive mechanisms take place that allow prolongation of apnoea beyond the limits attained by non-diving subjects, and preservation of oxygen stores during the dives. ...
Schagatay E - - 2001
This study addressed the interaction between short-term adaptation to apneas with face immersion and erythrocyte release from the spleen. Twenty healthy volunteers, including ten splenectomized subjects, participated. After prone rest, they performed five maximal-duration apneas with face immersion in 10 degrees C water, with 2-min intervals. Cardiorespiratory parameters and venous ...
Neubauer B - - 2001
OBJECTIVES: Increased ambient pressure and oxygen partial pressure (pO2) influence cardiovascular regulation during diving and caisson work. We measured the cardiac output (Q) in subjects who practiced moderate work at a usual diving depth of 30 m. METHODS: In 23 healthy male Navy divers who performed steady state bicycle exercises ...
González S - - 2001
This study set out to determine the possible influence of variations in atmospheric pressure on mortality in the Madrid Autonomous Region (MAR), taking into account the possible confounding effect of other atmospheric variables. The study was based on daily mortality data from the MAR Revenue and Excise Authority, meteorological data ...
Poulsen S A - - 2001
The synthesis of enantiomerically pure C-6 substituted pyrazolo[3,4-d]pyrimidines has been performed by aromatic nucleophilic substitution of 4-amino-6-chloro-1-phenylpyrazolo[3,4-rd]pyrimidine under conditions of high pressure at ambient temperature. Conventional synthetic conditions (reflux at atmospheric pressure) were unsuccessful. The S enantiomer 11 displayed higher affinity and selectivity for the adenosine A1 receptor than the ...
Darbin O - - 2001
In rat, helium pressures induce locomotor and motor activity which requires dopaminergic and N-methyl-D-aspartate (NMDA) receptor activities at striatal level. However, biochemical studies have suggested that pressure exposure may increase striatal glutamate level. We used microdialysis technique to study the effects of pressure on glutamate level in the striatum and ...
Bianchi-Demicheli F - - 2001
Objective: This study examined the influence of weather conditions on the incidence of outpatient emergency consultations at the Department of Obstetrics and Gynecology at the Regional Hospital in Lugano, Switzerland. Study Design: The medical records of all women who attended the outpatient emergency unit at the Department for Obstetrics and ...
Sheriff D D - - 2001
INTRODUCTION: In humans, +Gz exposure immediately preceded by exposure to zero or -Gz can result in unexpected incapacitation ("push-pull" effect). Our goals were to establish whether this phenomenon exists in rats and to evaluate the importance of varying the duration of -Gz exposure on magnitude of the push-pull effect on ...
Kawaguchi H - - 2001
Mechanical forces related to pressure and flow are important for cell hypertrophy and proliferation. To test the hypothesis that mechanosensors are present that are sensitive solely to pure atmospheric pressure in the absence of shear and tensile stresses. A pressure-loading apparatus was set up to examine the effects of atmospheric ...
Berberich J A - - 2000
Selection of biocompatible solvents is critical when designing bioprocessing applications for the in situ biphasic extraction of metabolic end-products. The prediction of the biocompatibility of supercritical and compressed solvents is more complicated than for liquid solvents, because their properties can change significantly with pressure and temperature. The activity of the ...
Riches P E - - 2000
The Knoop indenter has been used to characterise fully the Knoop microhardness (H(K)) anisotropy of compact bone. 2120 indentations were performed on mature ovine radii and a linear relationship was found between H(K) and the angle between the major diagonal of the indenter and the lamella boundaries (p<<0.001). H(K) increased ...
Sanz P D - - 2000
A comprehensive vision of the heat transfer process involved in high-pressure shift freezing (HPSF) is shown in comparison to the process at atmospheric pressure. In addition, a mathematical model to predict the freezing times is presented. This model takes into consideration the dependence of the thermophysical properties relating to temperature ...
Theron M - - 2000
Previous studies have suggested that the efficiency of oxidative phosphorylation in the freshwater eel (Anguilla anguilla) is increased after acclimation to high hydrostatic pressure. Analysis at atmospheric pressure of the respiratory chain complexes showed that, after 21 days at 10.1 MPa, the activity of complex II was decreased to approximately ...
Finn J P - - 2000
Barometric pressure exerts by far the greatest influence of the three environmental factors (barometric pressure, temperature and humidity) on power outputs from air-braked ergometers. The barometric pressure correction factor for power outputs from air-braked ergometers is in widespread use but apparently has never been empirically validated. Our experiment validated this ...
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