Using Multiple Barometers to Detect the Floor Location of Smart Phones with Built-in Barometric Sensors for Indoor Positioning

PubMed Central

Xia, Hao; Wang, Xiaogang; Qiao, Yanyou; Jian, Jun; Chang, Yuanfei

2015-01-01

Following the popularity of smart phones and the development of mobile Internet, the demands for accurate indoor positioning have grown rapidly in recent years. Previous indoor positioning methods focused on plane locations on a floor and did not provide accurate floor positioning. In this paper, we propose a method that uses multiple barometers as references for the floor positioning of smart phones with built-in barometric sensors. Some related studies used barometric formula to investigate the altitude of mobile devices and compared the altitude with the height of the floors in a building to obtain the floor number. These studies assume that the accurate height of each floor is known, which is not always the case. They also did not consider the difference in the barometric-pressure pattern at different floors, which may lead to errors in the altitude computation. Our method does not require knowledge of the accurate heights of buildings and stories. It is robust and less sensitive to factors such as temperature and humidity and considers the difference in the barometric-pressure change trends at different floors. We performed a series of experiments to validate the effectiveness of this method. The results are encouraging. PMID:25835189

Arduino Uno Microcontroller with Commercially Available Sensors Towards Generating Student Accessible Raw Meteorological Data

NASA Astrophysics Data System (ADS)

Henson, Gabrielle; Tanner, Meghan; Senevirathne, Indrajith

Microcontroller systems can be a boon to cost - effective techniques that can be used to enhance teaching at college level. We have used Arduino microcontroller coupled with commercially available sensors to systematically measure, record and analyze temperature, humidity and barometric pressure and to upload the real time raw data to cloud. Corresponding data will be available in classroom settings for predictions, analysis and simple weather forecasting. Setup was assembled via breadboard, wire and simple soldering with an Arduino Uno ATmega328P microcontroller connected to a PC. The microcontroller was programmed with Arduino Software while the bootloader was used to upload the code. Commercial DHT22 humidity and temperature sensor and BMP180 barometric pressure sensor were used to obtain relative humidity, temperature and the barometric pressure. System was mounted inside a weather resistant enclosure and data measurements were obtained and were uploaded onto the PC and then to cloud. Cloud data can be accessed via a shared link in a General Education class for multitude of purposes.

Effects of meteorological factors and the lunar cycle on onset of parturition in cows.

PubMed

Ammann, T; Hässig, M; Rüegg, S; Bleul, U

2016-04-01

The present paper summarizes a comprehensive retrospective study that was undertaken to investigate effects of meteorological factors and lunar cycle on gestation length and daily birth rate in cows. To this end, all cattle births in Switzerland between 2008 and 2010 (n=2,091,159) were related to detailed matched weather recordings. The study revealed some statistically significant effects of climate (temperature, barometric pressure, relative humidity) and weather (thunderstorms, heat index) on gestational length. Thunderstorms on the day before birth reduced the gestation length by 0.5 days. An increase in the birth rate was correlated with the temperature on the day before birth and the barometric pressure 3 days before birth. Differences in the barometric pressure >15hPa increased the birth rate by 4%. Nevertheless, the effects were not consistent and the modeled size of effect was so small that a clinical implication is unlikely. Although the daily birth rate was unevenly distributed across the lunar cycle, no clear pattern could be identified. Compared to the mean birth rate across the lunar cycle the highest daily birth rate was detected on day 4 after new moon (+1.9%) and the lowest on day 20 (-2.1%). Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Barometric pressure forcing on radon-222 and temperature in fumarolic gases: a tool to describe flow-rate dynamics

NASA Astrophysics Data System (ADS)

Richon, P.; Salaun, A.; Boudon, G.; Villemant, B.; Crispi, O.; Sabroux, J.

2010-12-01

We propose two conceptual models for the dynamics of fumarolic gases, during their ascent through the volcano plumbing, based on radon-222 and temperature data collected on fumaroles of La Soufrière volcano (Guadeloupe,FWI) together with local barometric pressure, and on a new interpretation of older data collected on Merapi volcano (1), Indonesia. All these in-situ measurements prove that the diurnal (24h, S1 barometric wave) and semidiurnal (12h, S2 barometric wave) variations in radon concentration are clearly observable, and positively or negatively correlated with barometric pressure variation. Two models are used to interpret this correlation. The first model, called “Accumulation mode”, is characterized by an initial and negligible deep radon-222 source and by a major contribution of radon-222 from conduit walls and connected fractures (emanation and exhalation mechanisms) during the gas ascent through the fumarolic system. This model is substantiated by a positive correlation between radon and pressure in the Merapi fumaroles. The second model, or “Decay mode”, is exemplified by a negative correlation between radon and pressure as measured in fumaroles at La Soufrière volcano. It is characterized by radioactive decay of a strong initial radon-222 source generated by a deeper reservoir (hydrothermal system or magmatic chamber) whereas contribution by conduit walls and connected fractures to the total radon-222 activity in the fumarole is comparatively minor during the transit time of the gas. In these two modes, it is possible to infer that, for transit times longer than ca. 21 days, the barometric pressure does not modulate the radon signal. Thus, the simultaneous monitoring of radon-222, temperature and barometric pressure provides a precise fumarole flowmeter. In addition, it is a tool to decipher shallow versus deep feeding of volcanic fumaroles that should prove useful for volcano monitoring. (1)Zimmer, M. & Erzinger, J. Continuous H2O, CO2, 222Rn and temperature measurements on Merapi Volcano, Indonesia. J. Volcanol. Geoth. Res. 125, 25-38 (2003).

Intracanal molar barometric pressure differentials at simulated altitude conditions - proof of concept study.

PubMed

Roberts, H W; Kirkpatrick, T C

2016-08-01

To evaluate whether objective data could be obtained regarding internal pressure conditions of a molar tooth with canals prepared but not filled exposed to reduced barometric pressures that could be experienced by aircrew. The root canals of five mandibular molars were prepared but not filled. Root apices were sealed with a resin-modified glass-ionomer liner and root surfaces sealed with a dental adhesive. The sealed root surfaces were then coated with a polyvinylsiloxane (PVS) adhesive and the teeth inserted into cylinders of PVS impression material to the level of the cervical enamel junction. Barometric pressure transducers were placed in the pulp chambers with the endodontic access sealed with cotton and a provisional restoration. The specimens were then subjected to a manually controlled, atmospheric altitude challenge consisting of a slow ascent and descent to a simulated 25 000 feet above sea level followed by a rapid altitude climb and descent. The real-time difference between intracanal and simulated atmospheric pressures were recorded and correlated (Pearson's, P = 0.05). No tooth material fractured, and there was no failure of the provisional restorations. Barometric pressures inside the closed prepared molar canals and the ambient atmospheric pressure were found to correlate (r(2)  = 0.97-0.99; P < 0.0001), but pressure equalization lags were observed. However, no differences greater than six pounds per square inch (310 torr) were noted. This pilot study established a protocol that demonstrated that objective data regarding barometric pressures within the prepared canals of molars can be obtained at simulated altitude conditions. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Relation of Total and Cardiovascular Death Rates to Climate System, Temperature, Barometric Pressure, and Respiratory Infection.

PubMed

Schwartz, Bryan G; Qualls, Clifford; Kloner, Robert A; Laskey, Warren K

2015-10-15

A distinct seasonal pattern in total and cardiovascular death rates has been reported. The factors contributing to this pattern have not been fully explored. Seven locations (average total population 71,354,000) were selected where data were available including relatively warm, cold, and moderate temperatures. Over the period 2004 to 2009, there were 2,526,123 all-cause deaths, 838,264 circulatory deaths, 255,273 coronary heart disease deaths, and 135,801 ST-elevation myocardial infarction (STEMI) deaths. We used time series and multivariate regression modeling to explore the association between death rates and climatic factors (temperature, dew point, precipitation, barometric pressure), influenza levels, air pollution levels, hours of daylight, and day of week. Average seasonal patterns for all-cause and cardiovascular deaths were very similar across the 7 locations despite differences in climate. After adjusting for multiple covariates and potential confounders, there was a 0.49% increase in all-cause death rate for every 1°C decrease. In general, all-cause, circulatory, coronary heart disease and STEMI death rates increased linearly with decreasing temperatures. The temperature effect varied by location, including temperature's linear slope, cubic fit, positional shift on the temperature axis, and the presence of circulatory death increases in locally hot temperatures. The variable effect of temperature by location suggests that people acclimatize to local temperature cycles. All-cause and circulatory death rates also demonstrated sizable associations with influenza levels, dew point temperature, and barometric pressure. A greater understanding of how climate, temperature, and barometric pressure influence cardiovascular responses would enhance our understanding of circulatory and STEMI deaths. Copyright © 2015 Elsevier Inc. All rights reserved.

Air density correction in ionization dosimetry.

PubMed

Christ, G; Dohm, O S; Schüle, E; Gaupp, S; Martin, M

2004-05-21

Air density must be taken into account when ionization dosimetry is performed with unsealed ionization chambers. The German dosimetry protocol DIN 6800-2 states an air density correction factor for which current barometric pressure and temperature and their reference values must be known. It also states that differences between air density and the attendant reference value, as well as changes in ionization chamber sensitivity, can be determined using a radioactive check source. Both methods have advantages and drawbacks which the paper discusses in detail. Barometric pressure at a given height above sea level can be determined by using a suitable barometer, or data downloaded from airport or weather service internet sites. The main focus of the paper is to show how barometric data from measurement or from the internet are correctly processed. Therefore the paper also provides all the requisite equations and terminological explanations. Computed and measured barometric pressure readings are compared, and long-term experience with air density correction factors obtained using both methods is described.

Radionuclide Gas Transport through Nuclear Explosion-Generated Fracture Networks

PubMed Central

Jordan, Amy B.; Stauffer, Philip H.; Knight, Earl E.; Rougier, Esteban; Anderson, Dale N.

2015-01-01

Underground nuclear weapon testing produces radionuclide gases which may seep to the surface. Barometric pumping of gas through explosion-fractured rock is investigated using a new sequentially-coupled hydrodynamic rock damage/gas transport model. Fracture networks are produced for two rock types (granite and tuff) and three depths of burial. The fracture networks are integrated into a flow and transport numerical model driven by surface pressure signals of differing amplitude and variability. There are major differences between predictions using a realistic fracture network and prior results that used a simplified geometry. Matrix porosity and maximum fracture aperture have the greatest impact on gas breakthrough time and window of opportunity for detection, with different effects between granite and tuff simulations highlighting the importance of accurately simulating the fracture network. In particular, maximum fracture aperture has an opposite effect on tuff and granite, due to different damage patterns and their effect on the barometric pumping process. From stochastic simulations using randomly generated hydrogeologic parameters, normalized detection curves are presented to show differences in optimal sampling time for granite and tuff simulations. Seasonal and location-based effects on breakthrough, which occur due to differences in barometric forcing, are stronger where the barometric signal is highly variable. PMID:26676058

Radionuclide Gas Transport through Nuclear Explosion-Generated Fracture Networks.

PubMed

Jordan, Amy B; Stauffer, Philip H; Knight, Earl E; Rougier, Esteban; Anderson, Dale N

2015-12-17

Underground nuclear weapon testing produces radionuclide gases which may seep to the surface. Barometric pumping of gas through explosion-fractured rock is investigated using a new sequentially-coupled hydrodynamic rock damage/gas transport model. Fracture networks are produced for two rock types (granite and tuff) and three depths of burial. The fracture networks are integrated into a flow and transport numerical model driven by surface pressure signals of differing amplitude and variability. There are major differences between predictions using a realistic fracture network and prior results that used a simplified geometry. Matrix porosity and maximum fracture aperture have the greatest impact on gas breakthrough time and window of opportunity for detection, with different effects between granite and tuff simulations highlighting the importance of accurately simulating the fracture network. In particular, maximum fracture aperture has an opposite effect on tuff and granite, due to different damage patterns and their effect on the barometric pumping process. From stochastic simulations using randomly generated hydrogeologic parameters, normalized detection curves are presented to show differences in optimal sampling time for granite and tuff simulations. Seasonal and location-based effects on breakthrough, which occur due to differences in barometric forcing, are stronger where the barometric signal is highly variable.

Objective classification of historical tropical cyclone intensity

NASA Astrophysics Data System (ADS)

Chenoweth, Michael

2007-03-01

Preinstrumental records of historical tropical cyclone activity require objective methods for accurately categorizing tropical cyclone intensity. Here wind force terms and damage reports from newspaper accounts in the Lesser Antilles and Jamaica for the period 1795-1879 are compared with wind speed estimates calculated from barometric pressure data. A total of 95 separate barometric pressure readings and colocated simultaneous wind force descriptors and wind-induced damage reports are compared. The wind speed estimates from barometric pressure data are taken as the most reliable and serve as a standard to compare against other data. Wind-induced damage reports are used to produce an estimated wind speed range using a modified Fujita scale. Wind force terms are compared with the barometric pressure data to determine if a gale, as used in the contemporary newspapers, is consistent with the modern definition of a gale. Results indicate that the modern definition of a gale (the threshold point separating the classification of a tropical depression from a tropical storm) is equivalent to that in contemporary newspaper accounts. Barometric pressure values are consistent with both reported wind force terms and wind damage on land when the location, speed and direction of movement of the tropical cyclone are determined. Damage reports and derived wind force estimates are consistent with other published results. Biases in ships' logbooks are confirmed and wind force terms of gale strength or greater are identified. These results offer a bridge between the earlier noninstrumental records of tropical cyclones and modern records thereby offering a method of consistently classifying storms in the Caribbean region into tropical depressions, tropical storms, nonmajor and major hurricanes.

An objective frequency domain method for subsurface characterisation using Earth and atmospheric tides

NASA Astrophysics Data System (ADS)

Cuthbert, M. O.; Acworth, I. R.; Halloran, L. J. S.; Rau, G. C.; Bernadi, T. L.

2017-12-01

It has long been recognised that hydraulic properties can be derived from the response of piezometric heads to tidal loadings. However, there is a degree of subjectivity in existing graphical approaches most commonly used to calculate barometric efficiency leading to uncertainties in derived values of compressible storage. Here we demonstrate a novel approach to remove these uncertainties by objectively deriving the barometric efficiency from groundwater hydraulic head responses using a frequency domain method. We take advantage of the presence of worldwide and ubiquitous atmospheric tide fluctuations which occur at 2 cycles per day (cpd). First we use a Fourier transform to calculate the amplitudes of the 2 cpd signals from co-located atmospheric pressure and hydraulic head time series measurements. Next we show how the Earth tide response at the same frequency can be quantified and removed so that this effect does not interfere with the calculation of the barometric efficiency. Finally, the ratio of the amplitude of the response at 2 cpd of hydraulic head to atmospheric pressure is used to quantify the barometric efficiency. This new method allows an objective quantification using `passive' in situ monitoring rather than resorting to aquifer pumping or laboratory tests. The minimum data requirements are 15 days duration of 6-hourly hydraulic head and atmospheric pressure measurements, and modelled Earth tide records which are readily conducted using freely available software. The new approach allows for a rapid and cost-effective alternative to traditional methods of estimating aquifer compressible storage properties without the subjectivity of existing approaches, and will be of importance to improving the spatial coverage of subsurface characterisation for groundwater resource evaluation and land subsidence assessment.

Radionuclide gas transport through nuclear explosion-generated fracture networks

DOE PAGES

Jordan, Amy B.; Stauffer, Philip H.; Knight, Earl E.; ...

2015-12-17

Underground nuclear weapon testing produces radionuclide gases which may seep to the surface. Barometric pumping of gas through explosion-fractured rock is investigated using a new sequentially-coupled hydrodynamic rock damage/gas transport model. Fracture networks are produced for two rock types (granite and tuff) and three depths of burial. The fracture networks are integrated into a flow and transport numerical model driven by surface pressure signals of differing amplitude and variability. There are major differences between predictions using a realistic fracture network and prior results that used a simplified geometry. Matrix porosity and maximum fracture aperture have the greatest impact on gasmore » breakthrough time and window of opportunity for detection, with different effects between granite and tuff simulations highlighting the importance of accurately simulating the fracture network. In particular, maximum fracture aperture has an opposite effect on tuff and granite, due to different damage patterns and their effect on the barometric pumping process. From stochastic simulations using randomly generated hydrogeologic parameters, normalized detection curves are presented to show differences in optimal sampling time for granite and tuff simulations. In conclusion, seasonal and location-based effects on breakthrough, which occur due to differences in barometric forcing, are stronger where the barometric signal is highly variable.« less

Radionuclide gas transport through nuclear explosion-generated fracture networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jordan, Amy B.; Stauffer, Philip H.; Knight, Earl E.

Underground nuclear weapon testing produces radionuclide gases which may seep to the surface. Barometric pumping of gas through explosion-fractured rock is investigated using a new sequentially-coupled hydrodynamic rock damage/gas transport model. Fracture networks are produced for two rock types (granite and tuff) and three depths of burial. The fracture networks are integrated into a flow and transport numerical model driven by surface pressure signals of differing amplitude and variability. There are major differences between predictions using a realistic fracture network and prior results that used a simplified geometry. Matrix porosity and maximum fracture aperture have the greatest impact on gasmore » breakthrough time and window of opportunity for detection, with different effects between granite and tuff simulations highlighting the importance of accurately simulating the fracture network. In particular, maximum fracture aperture has an opposite effect on tuff and granite, due to different damage patterns and their effect on the barometric pumping process. From stochastic simulations using randomly generated hydrogeologic parameters, normalized detection curves are presented to show differences in optimal sampling time for granite and tuff simulations. In conclusion, seasonal and location-based effects on breakthrough, which occur due to differences in barometric forcing, are stronger where the barometric signal is highly variable.« less

Temporal variations of radon in soil related to earthquakes.

PubMed

Planinić, J; Radolić, V; Lazanin, Z

2001-08-01

A radon detector with LR-115 nuclear track film was constructed for radon concentration measurements in soil. Temporal radon variations, as well as the barometric pressure, precipitation and temperature were measured for two years. Negative correlation between radon concentration in soil and barometric pressure was found. For some of the recorded earthquakes that occurred during the observation period, soil radon anomalies may be noticed one month before the quakes.

A model investigation of turbulence-driven pressure-pumping effects on the rate of diffusion of CO2, N2O, and CH4 through layered snowpacks

Treesearch

W. J. Massman; R. A. Sommerfeld; A. R. Mosier; K. F. Zeller; T.J . Hehn; S. G. Rochelle

1997-01-01

Pressure pumping at the Earth's surface is caused by short-period atmospheric turbulence, longer-period barometric changes, and quasi-static pressure fields induced by wind blowing across irregular topography. These naturally occurring atmospheric pressure variations induce periodic fluctuations in airflow through snowpacks, soils, and any other porous media at...

Stationary and transient thermal states of barometric pumping in the access pit of an underground quarry.

PubMed

Perrier, Frédéric; Le Mouël, Jean-Louis

2016-04-15

The transition zone between free and underground atmospheres hosts spectacular phenomena, as demonstrated by temperature measurements performed in the 4.6m diameter and 20m deep vertical access pit of an abandoned underground quarry located in Vincennes, near Paris. In summer, a stable stratification of the atmosphere is maintained, with coherent temperature variations associated with atmospheric pressure changes, with a barometric tide S2 larger than 0.1°C peak to peak. When the winter regime of turbulent cold air avalanches is initiated, stratification with pressure induced signals can be restored transiently in the upper part of the pit, while the lower part remains fully mixed and insensitive to pressure variations. The amplitude of the pressure to temperature transfer function increases with frequency below 5×10(-4)Hz, with values at 3×10(-5)Hz varying from 0.1°C·hPa(-1) at the bottom up to 2°C·hPa(-1) towards the top of the pit. These temperature variations are accounted for by cave breathing, which is pressure induced motion of air amplified by the large volume of the quarry. This understanding is supported by a numerical model including advective heat transport, heat diffusion, and heat exchange with the pit walls. Mean lifetime in the pit is of the order of 9 to 13h, and barometric pumping results in an effective ventilation rate of the quarry of the order of 10(-7)s(-1). This study illustrates the important role of barometric pumping in heat and matter transport between atmosphere and lithosphere. The resulting stationary and transient states, revealed in this pit, are probably a general feature of functioning interface systems, and therefore are an important aspect to consider in problems of contaminant transport, or the preservation of precious heritage such as rare ecosystems or painted caves. Copyright © 2016 Elsevier B.V. All rights reserved.

Analysis of water levels in the Frenchman Flat area, Nevada Test Site

USGS Publications Warehouse

Bright, D.J.; Watkins, S.A.; Lisle, B.A.

2001-01-01

Analysis of water levels in 21 wells in the Frenchman Flat area, Nevada Test Site, provides information on the accuracy of hydraulic-head calculations, temporal water-level trends, and potential causes of water-level fluctuations. Accurate hydraulic heads are particularly important in Frenchman Flat where the hydraulic gradients are relatively flat (less than 1 foot per mile) in the alluvial aquifer. Temporal water-level trends with magnitudes near or exceeding the regional hydraulic gradient may have a substantial effect on ground-water flow directions. Water-level measurements can be adjusted for the effects of barometric pressure, formation water density (from water-temperature measurements), borehole deviation, and land-surface altitude in selected wells in the Frenchman Flat area. Water levels in one well were adjusted for the effect of density; this adjustment was significantly greater (about 17 feet) than the adjustment of water levels for barometric pressure, borehole deviation, or land-surface altitude (less than about 4 feet). Water-level measurements from five wells exhibited trends that were statistically and hydrologically significant. Statistically significant water-level trends were observed for three wells completed in the alluvial aquifer (WW-5a, UE-5n, and PW-3), for one well completed in the carbonate aquifer (SM-23), and for one well completed in the quartzite confining unit (Army-6a). Potential causes of water-level fluctuations in wells in the Frenchman Flat area include changes in atmospheric conditions (precipitation and barometric pressure), Earth tides, seismic activity, past underground nuclear testing, and nearby pumping. Periodic water-level measurements in some wells completed in the carbonate aquifer indicate cyclic-type water-level fluctuations that generally correlate with longer term changes (more than 5 years) in precipitation. Ground-water pumping fromthe alluvial aquifer at well WW-5c and pumping and discharge from well RNM-2s appear to cause water-level fluctuations in nearby observation wells. The remaining known sources of water-level fluctuations do not appear to substantially affect water-level changes (seismic activity and underground nuclear testing) or do not affect changes over a period of more than 1 year (barometric pressure and Earth tides) in wells in the Frenchman Flat area.

Torricelli and the Ocean of Air: The First Measurement of Barometric Pressure

PubMed Central

2013-01-01

The recognition of barometric pressure was a critical step in the development of environmental physiology. In 1644, Evangelista Torricelli described the first mercury barometer in a remarkable letter that contained the phrase, “We live submerged at the bottom of an ocean of the element air, which by unquestioned experiments is known to have weight.” This extraordinary insight seems to have come right out of the blue. Less than 10 years before, the great Galileo had given an erroneous explanation for the related problem of pumping water from a deep well. Previously, Gasparo Berti had filled a very long lead vertical tube with water and showed that a vacuum formed at the top. However, Torricelli was the first to make a mercury barometer and understand that the mercury was supported by the pressure of the air. Aristotle stated that the air has weight, although this was controversial for some time. Galileo described a method of measuring the weight of the air in detail, but for reasons that are not clear his result was in error by a factor of about two. Torricelli surmised that the pressure of the air might be less on mountains, but the first demonstration of this was by Blaise Pascal. The first air pump was built by Otto von Guericke, and this influenced Robert Boyle to carry out his classical experiments of the physiological effects of reduced barometric pressure. These were turning points in the early history of high-altitude physiology. PMID:23455767

Torricelli and the ocean of air: the first measurement of barometric pressure.

PubMed

West, John B

2013-03-01

The recognition of barometric pressure was a critical step in the development of environmental physiology. In 1644, Evangelista Torricelli described the first mercury barometer in a remarkable letter that contained the phrase, "We live submerged at the bottom of an ocean of the element air, which by unquestioned experiments is known to have weight." This extraordinary insight seems to have come right out of the blue. Less than 10 years before, the great Galileo had given an erroneous explanation for the related problem of pumping water from a deep well. Previously, Gasparo Berti had filled a very long lead vertical tube with water and showed that a vacuum formed at the top. However, Torricelli was the first to make a mercury barometer and understand that the mercury was supported by the pressure of the air. Aristotle stated that the air has weight, although this was controversial for some time. Galileo described a method of measuring the weight of the air in detail, but for reasons that are not clear his result was in error by a factor of about two. Torricelli surmised that the pressure of the air might be less on mountains, but the first demonstration of this was by Blaise Pascal. The first air pump was built by Otto von Guericke, and this influenced Robert Boyle to carry out his classical experiments of the physiological effects of reduced barometric pressure. These were turning points in the early history of high-altitude physiology.

Effects of periodic atmospheric pressure variation on radon entry into buildings

NASA Astrophysics Data System (ADS)

Tsang, Y. W.; Narasimhan, T. N.

1992-06-01

Using a mathematical model, we have investigated the temporal variations of radon entry into a house basement in the presence of time-dependent periodic variations of barometric pressure as well as a persistent small steady depressurization within the basement. The tool for our investigation is an integral finite difference numerical code which can solve for both diffusive and advective flux of radon in the soil gas which is treated as a slightly compressible fluid. Two different boundary conditions at the house basement are considered: (1) a dirt floor basement so that diffusion is equally or more important than advective transport, and (2) an "impermeable" cement basement except for a 1-cm-wide crack near the perimeter of the basement floor; in which case, advective transport of radon flux dominates. Two frequencies of barometric pressure fluctuation with representative values of amplitudes, based on a Fourier decomposition of barometric pressure data, were chosen in this study: one with a short period of 0.5 hour with pressure amplitude of 50 Pa, the other a diurnal variation with a period of 24 hours with the typical pressure amplitude of 250 Pa. For a homogeneous soil medium with soil permeability to air between 10-13 and 10-10 m2, we predict that the barometric fluctuations increase the radon entry into the basement by up to 120% of the steady radon inflow into the basement owing to a steady depressurization of 5 Pa. If soil permeability heterogeneity is present, such as the presence of a thin layer of higher permeability aggregate immediately below the basement floor, radon flux due to atmospheric pumping is further increased. Effects of pressure pumping on radon entry are also compared to diffusion-only transport when the steady depressurization is absent. It is found that contribution to radon entry is significant for the basement crack configuration. In particular, for pressure pumping at 0.5-hour period and for a homogeneous medium of permeability of 10-10 m2, the radon entry is a factor of 10 larger than that predicted by the diffusion-only transport. This may help to explain indoor radon concentrations during times of low steady state driving force. Extending beyond radon transport, the results of this case study establish the importance of transient advective transport resulting from atmospheric pressure variation. These results may have relevance in the estimations of the transfer of trace gases such as methane and nitrous oxide across the soil-atmosphere interface and their impact on global climate changes.

Weather forecasting by insects: modified sexual behaviour in response to atmospheric pressure changes.

PubMed

Pellegrino, Ana Cristina; Peñaflor, Maria Fernanda Gomes Villalba; Nardi, Cristiane; Bezner-Kerr, Wayne; Guglielmo, Christopher G; Bento, José Maurício Simões; McNeil, Jeremy N

2013-01-01

Prevailing abiotic conditions may positively or negatively impact insects at both the individual and population levels. For example while moderate rainfall and wind velocity may provide conditions that favour development, as well as movement within and between habitats, high winds and heavy rains can significantly decrease life expectancy. There is some evidence that insects adjust their behaviours associated with flight, mating and foraging in response to changes in barometric pressure. We studied changes in different mating behaviours of three taxonomically unrelated insects, the curcurbit beetle, Diabrotica speciosa (Coleoptera), the true armyworm moth, Pseudaletia unipuncta (Lepidoptera) and the potato aphid, Macrosiphum euphorbiae (Hemiptera), when subjected to natural or experimentally manipulated changes in atmospheric pressure. In response to decreasing barometric pressure, male beetles exhibited decreased locomotory activity in a Y-tube olfactometer with female pheromone extracts. However, when placed in close proximity to females, they exhibited reduced courtship sequences and the precopulatory period. Under the same situations, females of the true armyworm and the potato aphid exhibited significantly reduced calling behaviour. Neither the movement of male beetles nor the calling of armyworm females differed between stable and increasing atmospheric pressure conditions. However, in the case of the armyworm there was a significant decrease in the incidence of mating under rising atmospheric conditions, suggesting an effect on male behaviour. When atmospheric pressure rose, very few M. euphorbiae oviparae called. This was similar to the situation observed under decreasing conditions, and consequently very little mating was observed in this species except under stable conditions. All species exhibited behavioural modifications, but there were interspecific differences related to size-related flight ability and the diel periodicity of mating activity. We postulate that the observed behavioral modifications, especially under decreasing barometric pressure would reduce the probability of injury or death under adverse weather conditions.

OTEC gas desorption studies

NASA Astrophysics Data System (ADS)

Chen, F. C.; Golshani, A.

1982-02-01

Experiments on deaeration in packed columns and barometric intake systems, and with hydraulic air compression for open-cycle OTEC systems are reported. A gas desorption test loop consisting of water storage tanks, a vacuum system, a liquid recirculating system, an air supply, a column test section, and two barometric leg test sections was used to perform the tests. The aerated water was directed through columns filled with either ceramic Raschig rings or plastic pall rings, and the system vacuum pressure, which drives the deaeration process, was found to be dependent on water velocity and intake pipe height. The addition of a barometric intake pipe increased the deaeration effect 10%, and further tests were run with lengths of PVC pipe as potential means for noncondensibles disposal through hydraulic air compression. Using the kinetic energy from the effluent flow to condense steam in the noncondensible stream improved the system efficiency.

Total dissolved gas, barometric pressure, and water temperature data, lower Columbia River, Oregon and Washington, 1996

USGS Publications Warehouse

Tanner, Dwight Q.; Harrison, Howard E.; McKenzie, Stuart W.

1996-01-01

Increased levels of total dissolved gas pressure can cause gas-bubble trauma in fish downstream from dams on the Columbia River. In cooperation with the U.S. Army Corps of Engineers, the U.S. Geological Survey collected data on total dissolved gas pressure, barometric pressure, water temperature, and dissolved oxygen pressure at 11 stations on the lower Columbia River from the John Day forebay (river mile 215.6) to Wauna Mill (river mile 41.9) from March to September 1996. Methods of data collection, review, and processing are described in this report. Summaries of daily minimum, maximum, and mean hourly values are presented for total dissolved gas pressure, barometric pressure, and water temperature. Hourly values for these parameters are presented graphically. Dissolved oxygen data are not presented in this report because the quality-control data show that the data have poor precision and high bias. Suggested changes to monitoring procedures for future studies include (1) improved calibration procedures for total dissolved gas and dissolved oxygen to better define accuracy at elevated levels of supersaturation and (2) equipping dissolved oxygen sensors with stirrers because river velocities at the shoreline monitoring stations probably cannot maintain an adequate flow of water across the membrane surface of the dissolved oxygen sensor.

Hazards of high altitude decompression sickness during falls in barometric pressure from 1 atm to a fraction thereof

NASA Technical Reports Server (NTRS)

Genin, A. M.

1980-01-01

Various tests related to studies concerning the effects of decompression sicknesses at varying pressure levels and physical activity are described. The tests indicate that there are no guarantees of freedom from decompression sicknesses when man transitions from a normally oxygenated normobaric nitrogen-oxygen atmosphere into an environment having a 0.4 atm or lower pressure and he is performing physical work.

Do weather changes influence pain levels in women with fibromyalgia, and can psychosocial variables moderate these influences?

NASA Astrophysics Data System (ADS)

Smedslund, Geir; Eide, Hilde; Kristjansdottir, Ólöf Birna; Nes, Andrea Aparecida Gonçalves; Sexton, Harold; Fors, Egil A.

2014-09-01

The aim of this study was to examine the association between fibromyalgia pain and weather, and to investigate whether psychosocial factors influence this relationship. Women with chronic widespread pain/fibromyalgia ( N = 50) enrolled in a larger study, were recruited from a 4-week inpatient rehabilitation program in Norway ( 2009-2010), and reported their pain and psychological factors up to three times per day (morning, afternoon, evening) for 5 weeks. These ratings were then related to the official local weather parameters. Barometric pressure recorded simultaneously impacted pain significantly while temperature, relative humidity, and solar flux did not. No psychological variables influenced the weather-pain interaction. No weather parameter predicted change in the subsequent pain measures. The magnitude of the inverse association between pain and barometric pressure was very small, and none of the psychological variables studied influenced the association between pain and barometric pressure. All in all, the evidence for a strong weather-pain association in fibromyalgia seems limited at best.

High altitude simulation, substance P and airway rapidly adapting receptor activity in rabbits.

PubMed

Bhagat, R; Yasir, A; Vashisht, A; Kulshreshtha, R; Singh, S B; Ravi, K

2011-09-15

To investigate whether there is a change in airway rapidly adapting receptor (RAR) activity during high altitude exposure, rabbits were placed in a high altitude simulation chamber (barometric pressure, 429 mm Hg). With 12 h exposure, when there was pulmonary congestion, an increase in basal RAR activity was observed. With 36 h exposure, when there was alveolar edema, there was a further increase in basal RAR activity. In these backgrounds, there was an increase in the sensitivity of the RARs to substance P (SP). To assess whether there was an increase in lung SP level, neutral endopeptidase activity was determined which showed a decrease in low barometric pressure exposed groups. It is concluded that along with the SP released, pulmonary congestion and edema produced, respectively by different durations of low barometric pressure exposure cause a progressive increase in RAR activity which may account for the respiratory symptoms reported in climbers who are unacclimatized. Copyright © 2011 Elsevier B.V. All rights reserved.

2010 weather and aeolian sand-transport data from the Colorado River corridor, Grand Canyon, Arizona

USGS Publications Warehouse

Dealy, Timothy P.; East, Amy E.; Fairley, Helen C.

2014-01-01

Measurements of weather parameters and aeolian sand transport were made in 2010 near selected archeological sites in the Colorado River corridor through Grand Canyon, Arizona. Data collected in 2010 indicate event- and seasonal-scale variations in rainfall, wind, temperature, humidity, and barometric pressure. Differences in weather patterns between 2009 and 2010 included a slightly later spring windy season, greater spring precipitation and annual rainfall totals, and a later onset and length of the reduced diurnal barometric-pressure fluctuations commonly associated with summer monsoon conditions. The increase in spring precipitation was consistent with the 2010 spring El Niño conditions compared to the 2009 spring La Niña conditions, whereas the subsequent transition to an El Niño-Southern Oscillation neutral phase appeared to delay the reduction in diurnal barometric fluctuations.

Correction of wheat meal falling number to a common barometric pressure at simulated laboratory elevations of 0 to 1500 meters

USDA-ARS?s Scientific Manuscript database

Falling number, a procedure that indirectly gauges germination enzyme activity in wheat by its measurement of the viscous behavior of a heated starch-water mixture, is affected by the immersion water bath temperature. Maintained at boiling point, the water bath temperature is determined by barometr...

The major influence of the atmosphere on intracranial pressure: an observational study.

PubMed

Herbowski, Leszek

2017-01-01

The impact of the atmosphere on human physiology has been studied widely within the last years. In practice, intracranial pressure is a pressure difference between intracranial compartments and the surrounding atmosphere. This means that gauge intracranial pressure uses atmospheric pressure as its zero point, and therefore, this method of pressure measurement excludes the effects of barometric pressure's fluctuation. The comparison of these two physical quantities can only take place through their absolute value relationship. The aim of this study is to investigate the direct effect of barometric pressure on the absolute intracranial pressure homeostasis. A prospective observational cross-sectional open study was conducted in Szczecin, Poland. In 28 neurosurgical patients with suspected normal-pressure hydrocephalus, intracranial intraventricular pressure was monitored in a sitting position. A total of 168 intracranial pressure and atmospheric pressure measurements were performed. Absolute atmospheric pressure was recorded directly. All values of intracranial gauge pressure were converted to absolute pressure (the sum of gauge intracranial pressure and local absolute atmospheric pressure). The average absolute mean intracranial pressure in the patients is 1006.6 hPa (95 % CI 1004.5 to 1008.8 hPa, SEM 1.1), and the mean absolute atmospheric pressure is 1007.9 hPa (95 % CI 1006.3 to 1009.6 hPa, SEM 0.8). The observed association between atmospheric and intracranial pressure is strongly significant (Spearman correlation r = 0.87, p < 0.05) and all the measurements are perfectly reliable (Bland-Altman coefficient is 4.8 %). It appears from this study that changes in absolute intracranial pressure are related to seasonal variation. Absolute intracranial pressure is shown to be impacted positively by atmospheric pressure.

The major influence of the atmosphere on intracranial pressure: an observational study

NASA Astrophysics Data System (ADS)

Herbowski, Leszek

2017-01-01

The impact of the atmosphere on human physiology has been studied widely within the last years. In practice, intracranial pressure is a pressure difference between intracranial compartments and the surrounding atmosphere. This means that gauge intracranial pressure uses atmospheric pressure as its zero point, and therefore, this method of pressure measurement excludes the effects of barometric pressure's fluctuation. The comparison of these two physical quantities can only take place through their absolute value relationship. The aim of this study is to investigate the direct effect of barometric pressure on the absolute intracranial pressure homeostasis. A prospective observational cross-sectional open study was conducted in Szczecin, Poland. In 28 neurosurgical patients with suspected normal-pressure hydrocephalus, intracranial intraventricular pressure was monitored in a sitting position. A total of 168 intracranial pressure and atmospheric pressure measurements were performed. Absolute atmospheric pressure was recorded directly. All values of intracranial gauge pressure were converted to absolute pressure (the sum of gauge intracranial pressure and local absolute atmospheric pressure). The average absolute mean intracranial pressure in the patients is 1006.6 hPa (95 % CI 1004.5 to 1008.8 hPa, SEM 1.1), and the mean absolute atmospheric pressure is 1007.9 hPa (95 % CI 1006.3 to 1009.6 hPa, SEM 0.8). The observed association between atmospheric and intracranial pressure is strongly significant (Spearman correlation r = 0.87, p < 0.05) and all the measurements are perfectly reliable (Bland-Altman coefficient is 4.8 %). It appears from this study that changes in absolute intracranial pressure are related to seasonal variation. Absolute intracranial pressure is shown to be impacted positively by atmospheric pressure.

Foundations of space biology and medicine. Volume 2, book 1: Ecological and physiological bases of space biology and medicine

NASA Technical Reports Server (NTRS)

Calvin, M. (Editor); Gazenko, O. G. (Editor)

1975-01-01

Barometric pressure, gas composition, toxicity, and thermal exchange of spacecraft cabin atmospheres are discussed. Effects of gravitation, acceleration, weightlessness, noise, and vibration on human behavior and performance during space flight are also described.

The effects of daily weather variables on psychosis admissions to psychiatric hospitals

NASA Astrophysics Data System (ADS)

McWilliams, Stephen; Kinsella, Anthony; O'Callaghan, Eadbhard

2013-07-01

Several studies have noted seasonal variations in admission rates of patients with psychotic illnesses. However, the changeable daily meteorological patterns within seasons have never been examined in any great depth in the context of admission rates. A handful of small studies have posed interesting questions regarding a potential link between psychiatric admission rates and meteorological variables such as environmental temperature (especially heat waves) and sunshine. In this study, we used simple non-parametric testing and more complex ARIMA and time-series regression analysis to examine whether daily meteorological patterns (wind speed and direction, barometric pressure, rainfall, sunshine, sunlight and temperature) exert an influence on admission rates for psychotic disorders across 12 regions in Ireland. Although there were some weak but interesting trends for temperature, barometric pressure and sunshine, the meteorological patterns ultimately did not exert a clinically significant influence over admissions for psychosis. Further analysis is needed.

Revisiting borehole strain, typhoons, and slow earthquakes using quantitative estimates of precipitation-induced strain changes

NASA Astrophysics Data System (ADS)

Hsu, Ya-Ju; Chang, Yuan-Shu; Liu, Chi-Ching; Lee, Hsin-Ming; Linde, Alan T.; Sacks, Selwyn I.; Kitagawa, Genshio; Chen, Yue-Gau

2015-06-01

Taiwan experiences high deformation rates, particularly along its eastern margin where a shortening rate of about 30 mm/yr is experienced in the Longitudinal Valley and the Coastal Range. Four Sacks-Evertson borehole strainmeters have been installed in this area since 2003. Liu et al. (2009) proposed that a number of strain transient events, primarily coincident with low-barometric pressure during passages of typhoons, were due to deep-triggered slow slip. Here we extend that investigation with a quantitative analysis of the strain responses to precipitation as well as barometric pressure and the Earth tides in order to isolate tectonic source effects. Estimates of the strain responses to barometric pressure and groundwater level changes for the different stations vary over the ranges -1 to -3 nanostrain/millibar(hPa) and -0.3 to -1.0 nanostrain/hPa, respectively, consistent with theoretical values derived using Hooke's law. Liu et al. (2009) noted that during some typhoons, including at least one with very heavy rainfall, the observed strain changes were consistent with only barometric forcing. By considering a more extensive data set, we now find that the strain response to rainfall is about -5.1 nanostrain/hPa. A larger strain response to rainfall compared to that to air pressure and water level may be associated with an additional strain from fluid pressure changes that take place due to infiltration of precipitation. Using a state-space model, we remove the strain response to rainfall, in addition to those due to air pressure changes and the Earth tides, and investigate whether corrected strain changes are related to environmental disturbances or tectonic-original motions. The majority of strain changes attributed to slow earthquakes seem rather to be associated with environmental factors. However, some events show remaining strain changes after all corrections. These events include strain polarity changes during passages of typhoons (a characteristic that is not anticipated from our estimates of the precipitation transfer function) that are more readily explained in terms of tectonic-origin motions, but clearly the triggering argument is now weaker than that presented in Liu et al. (2009). Additional on-site water level sensors and rain gauges will provide data critical for a more complete understanding, including the currently unresolved issue of why, for some typhoons, there appears to be a much smaller transfer function for precipitation-induced strain changes.

Ventilatory acclimatization to hypoxia in mice: Methodological considerations.

PubMed

Ivy, Catherine M; Scott, Graham R

2017-01-01

We examined ventilatory acclimatization to hypoxia (VAH) in CD1 mice, and contrasted results obtained using the barometric method on unrestrained mice with pneumotachography and pulse oximetry on restrained mice. Responses to progressive step reductions in O 2 fraction (21%-8%) were assessed in mice acclimated to normoxia and hypobaric hypoxia (barometric pressure of 60kPa for 6-8 weeks). Hypoxia acclimation increased the hypoxic ventilatory response (primarily by increasing breathing frequency rather than tidal volume), arterial O 2 saturation (Sa O2 ) and heart rate in deep hypoxia, hypoxic chemosensitivity (ventilatory O 2 /CO 2 equivalents versus Sa O2 ), and respiratory water loss, and it blunted the hypoxic depression of metabolism and body temperature. Although some effects of hypoxia acclimation were qualitatively similar between methods, the effects were often greater in magnitude when assessed using pneumotachography. Furthermore, whereas hypoxia acclimation reduced ventilatory O 2 equivalent and increased pulmonary O 2 extraction in barometric experiments, it had the opposite effects in pneumotachography experiments. Our findings highlight the importance of considering the impact of how breathing is measured on the apparent responses to hypoxia. Copyright © 2016 Elsevier B.V. All rights reserved.

Crepuscular flight activity of an invasive insect governed by interacting abiotic factors

Treesearch

Yigen Chen; Steven J. Seybold

2014-01-01

Seasonal and diurnal flight patterns of the invasive walnut twig beetle, Pityophthorus juglandis, were assessed between 2011 and 2014 in northern California, USA in the context of the effects of ambient temperature, light intensity, wind speed, and barometric pressure. Pityophthorus juglandis generally initiated flight in late...

Nature's wrath-The effect of weather on pain following orthopaedic trauma.

PubMed

Shulman, Brandon S; Marcano, Alejandro I; Davidovitch, Roy I; Karia, Raj; Egol, Kenneth A

2016-08-01

Despite frequent complaints by orthopaedic trauma patients, to our knowledge there is no data regarding weather's effect on pain and function following acute and chronic fracture. The aim of our study was to investigate the influence of daily weather conditions on patient reported pain and functional status. We retrospectively examined prospectively collected data from 2369 separate outpatient visits of patients recovering from operative management of acute tibial plateau fractures, acute distal radius fractures, and chronic fracture nonunions. Pain and functional status were assessed using a visual analogue scale (VAS) and the DASH and SMFA functional indexes. For each visit date, the mean temperature, difference between mean temperature and expected temperature, dew point, mean humidity, amount of rain, amount of snow, and barometric pressure were recorded. Statistical analysis was run to search for associations between weather data and patient reported pain and function. Low barometric pressure was associated with increased pain across all patient visits (p=0.007) and for patients at 1-year follow-up only (p=0.005). At 1-year follow-up, high temperature (p=0.021) and high humidity (p=0.030) were also associated with increased pain. No significant association was noted between weather data and patient reported functional status at any follow-up interval. Patient complaints of weather influencing pain after orthopaedic trauma are valid. While pain in the immediate postoperative period is most likely dominated by incisional and soft tissue injuries, as time progresses barometric pressure, temperature, and humidity impact patient pain levels. Affirming and counseling that pain may vary based on changing weather conditions can help manage patient expectations and improve satisfaction. Copyright © 2016 Elsevier Ltd. All rights reserved.

ALTIMETER ERRORS,

DTIC Science & Technology

CIVIL AVIATION, *ALTIMETERS, FLIGHT INSTRUMENTS, RELIABILITY, ERRORS , PERFORMANCE(ENGINEERING), BAROMETERS, BAROMETRIC PRESSURE, ATMOSPHERIC TEMPERATURE, ALTITUDE, CORRECTIONS, AVIATION SAFETY, USSR.

Associations between weather conditions and clinical symptoms in patients with hip osteoarthritis: a 2-year cohort study.

PubMed

Dorleijn, Desirée M J; Luijsterburg, Pim A J; Burdorf, Alex; Rozendaal, Rianne M; Verhaar, Jan A N; Bos, Pieter K; Bierma-Zeinstra, Sita M A

2014-04-01

The goal of this study was to assess whether there is an association between ambient weather conditions and patients' clinical symptoms in patients with hip osteoarthritis (OA). The design was a cohort study with a 2-year follow-up and 3-monthly measurements and prospectively collected data on weather variables. The study population consisted of 222 primary care patients with hip OA. Weather variables included temperature, wind speed, total amount of sun hours, precipitation, barometric pressure, and relative humidity. The primary outcomes were severity of hip pain and hip disability as measured with the Western Ontario and McMasters University Osteoarthritis Index (WOMAC) pain and function subscales. Associations between hip pain and hip disability and the weather variables were assessed using crude and multivariate adjusted linear mixed-model analysis for repeated measurements. On the day of questionnaire completion, mean relative humidity was associated with WOMAC pain (estimate 0.1; 95% confidence interval=0.0-0.2; P=.02). Relative humidity contributed < or = 1% to the explained within-patient variance and between-patient variance of the WOMAC pain score. Mean barometric pressure was associated with WOMAC function (estimate 0.1; 95% confidence interval=0.0-0.1; P=.02). Barometric pressure contributed < or = 1% to the explained within-patient variance and between-patient variance of the WOMAC function score. The other weather variables were not associated with the WOMAC pain or function score. Our results support the general opinion of OA patients that barometric pressure and relative humidity influence perceived OA symptoms. However, the contribution of these weather variables (< or = 1%) to the severity of OA symptoms is not considered to be clinically relevant. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Experimental exposure of rats to methylene chloride at varying controlled barometric altitudes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lillquist, D.R.

1990-01-01

This study investigated combined effects of three methylene chloride (MC) volume/volume concentrations (0,50, and 500 ppm) at three controlled barometric altitudes (760, 640, and 560 torr). This provided a three by three study design. For each scenario, three altitude acclimated (6 days) adult male rats were studied for eight hours in a nose-only inhalation chamber. Blood (0.35 mL) was drawn from the cannulated left carotid artery of each rat at 0, 0.5, 1, 2, 4, and 8 hours and hematocrit, pO[sub 2], pCO[sub 2], pH , total hemoglobin (Hb) and carboxyhemoglobin (CHb) were measured. Time, MC concentration and altitude hadmore » significant effects on CHb production. CHb increased with increasing MC concentration over time. Increased barometric altitude (reduced partial pressure of MC vapor at altitude for equal ppm concentrations) resulted in lower blood CHb levels. A statistical model was derived to explain variation in CHb levels for these three independent variables (r = 0.983). The data were applied to an equation assessing the impact of altitude, MC concentration and time on the potential oxygen carrying capacity (POCC) of blood. The POCC of HB in the blood was calculated using blood Hb, CHb levels, Hb oxygen saturation (based on the blood pO[sub 2] and the oxygen dissociation curve for rats), and oxygen binding potential of Hb. It was determined for the altitudes and MC concentrations used, polycythemia associated with increased altitude had a greater impact on POCC than decreased pO[sub 2]. A regression equation was derived modeling variation in POCC of blood for the three independent variables (r = 0.995). This study demonstrated that altitude affects airborne ppm MC concentrations. This ultimately impacts CHb levels and oxygen carrying capacity of the blood. These finding indicate that occupationally acceptable ppm MC exposure levels at altitude do need barometric pressure correction.« less

Atmospheric effects on the underground muon intensity

NASA Technical Reports Server (NTRS)

Fenton, A. G.; Fenton, K. B.; Humble, J. E.; Hyland, G. B.

1985-01-01

It has previously been reported that the barometric pressure coefficient observed for muons at Poatina (vertical absorber depth 357 hg/sq cm) appears to be appreciably higher than would be expected from atmospheric absorption alone. There is a possibility that the effect is due to an upper atmospheric temperature effect arising from an inverse correlation of surface pressure with stratospheric temperature. A new proportional telescope is discussed which has been operating at Poatina since about the beginning of 83 and which has a long term stability suitable for studying variations of atmospheric origin.

Controls on Thermal Discharge in Yellowstone NAtional Park, Wyoming

NASA Astrophysics Data System (ADS)

Mohrmann, Jacob Steven

2007-10-01

Significant fluctuations in discharge occur in hot springs in Yellowstone National Park on a seasonal to decadal scale (Ingebritsen et al., 2001) and an hourly scale (Vitale, 2002). The purpose of this study was to determine the interval of the fluctuations in discharge and to explain what causes those discharge patterns in three thermally influenced streams in Yellowstone National Park. By monitoring flow in these streams, whose primary source of input is thermal discharge, we were able to find several significant patterns of discharge fluctuations. Patterns were found by using two techniques of spectral analysis. The spectral analyses completed involved using the program "R" as well as Microsoft Excel, both of which use Fourier transforms. The Fourier transform is a linear operator that identifies frequencies in the original function. Stream flow data were collected using a FloDar open channel flow monitor. The flow meter collected data at15-minute intervals at White Creek and Rabbit Creek for a period of approximately two weeks each during the Fall. Flow data were also used from 15-minute data interval from a USGS gaging station at Tantalus Creek. Patterns of discharge fluctuation were found in each stream. By comparing spectral analysis results of flow data with spectral analysis of published tide data and barometric pressure data, connections were drawn between fluctuations in tidal and barometric-pressure patterns and flow patterns. Also, visual comparisons used to identify potential correspondence with earthquakes and precipitation events. At Tantalus Creek, patterns were affected only by barometric pressure changes. At White Creek, one pattern was attributed to barometric pressure fluctuations, and another pattern was found that could be associated with earth-tide forces. At Rabbit Creek, these patterns were absent. A pattern at 8.55 hours, which could not be attributed to barometric pressure or earth tide forces, was found at Rabbit and White Creeks. The 8.55 hour pattern in discharge found at both Rabbit and White Creeks may suggest a physical link between the sites, which are close (2.5 km). The time pattern could be a result of a shared hydrothermal aquifer, convectively heating and discharging at both streams. However, the common time pattern could also be the result of independent factors, which coincidentally caused a similar time pattern.

Weather. Third Grade. Revised. Anchorage School District Elementary Science Program.

ERIC Educational Resources Information Center

Defendorf, Jean, Ed.

This resource book introduces third-grade children to the environment by studying the weather and its effects. Lessons are provided including: (1) constructing a weather diary; (2) thermometers; (3) clouds; (4) barometric pressure; (5) wind vanes; (6) heating and cooling air; and (7) analyzing weather data. Each lesson includes a listing of…

BAROMETRIC AND WATER-SURFACE WAVES PRODUCED BY MIKE SHOT

DTIC Science & Technology

Barometric and water -surface waves generated by Mike shot were studied by means of 25 instruments in 19 locations in the Pacific Basin ranging from...on the tops of two mounts. The first water waves arriving at Eniwetok Island apparently traveled along paths outside the lagoon. At several of the...stations there were two distinct arrivals of water waves, the first apparently being driven by the propagated rise in atmospheric pressure caused by the

Effect of the barometric phase transition of a DMPA bilayer on the lipid/water interface. An atomistic description by molecular dynamics simulation.

PubMed

Casares, J J Giner; Camacho, L; Romero, M T Martín; Cascales, J J López

2007-12-13

Understanding the structure and dynamics of phospholipid bilayers is of fundamental relevance in biophysics, biochemistry, and chemical physics. Lipid Langmuir monolayers are used as a model of lipid bilayers, because they are much more easily studied experimentally, although some authors question the validity of this model. With the aim of throwing light on this debate, we used molecular dynamics simulations to obtain an atomistic description of a membrane of dimyristoylphosphatidic acid under different surface pressures. Our results show that at low surface pressure the interdigitation between opposite lipids (that is, back-to-back interactions) controls the system structure. In this setting and due to the absence of this effect in the Langmuir monolayers, the behavior between these two systems differs considerably. However, when the surface pressure increases the lipid interdigitation diminishes and so monolayer and bilayer behavior converges. In this work, four computer simulations were carried out, subjecting the phospholipids to lateral pressures ranging from 0.17 to 40 mN/m. The phospholipids were studied in their charged state because this approach is closer to the experimental situation. Special attention was paid to validating our simulation results by comparison with available experimental data, therebeing in general excellent agreement between experimental and simulation data. In addition, the properties of the lipid/solution interface associated with the lipid barometric phase transition were studied.

Complication Rates in Altitude Restricted Patients Following Aeromedical Evacuation

DTIC Science & Technology

2016-04-01

humidity and temperature , reduced barometric pressure and oxygen levels, increased vibration, trapped gas expansion, and serious n oise, not to...correlated to PFC and PFC-100 rates. This finding suggests that aggressive prescribing of CARs may have a salutary effect on postflight complication...suggests that aggressive prescribing of CARs may have a salutary effect on postflight complication rates and bears further investigation. KEYWORDS: cabin

The Effect of Venue and Wind on the Distance of a Hammer Throw

ERIC Educational Resources Information Center

Hunter, Iain

2005-01-01

In track and field, gravity and air resistance act on the hammer after it has been released. Both of these forces depend on altitude and latitude. In addition, air resistance also depends on wind, temperature, humidity, and barometric pressure. Often, air resistance and varying gravity throughout the earth are not considered when throwing…

Relationship between air mass type and emergency department visits for migraine headache across the Triangle region of North Carolina

NASA Astrophysics Data System (ADS)

Elcik, Christopher; Fuhrmann, Christopher M.; Mercer, Andrew E.; Davis, Robert E.

2017-12-01

An estimated 240 million people worldwide suffer from migraines. Because migraines are often debilitating, understanding the mechanisms that trigger them is crucial for effective prevention and treatment. Synoptic air mass types and emergency department (ED) visits for migraine headaches were examined over a 7-year period within a major metropolitan area of North Carolina to identify potential relationships between large-scale meteorological conditions and the incidence of migraine headaches. Barometric pressure changes associated with transitional air masses, or changing weather patterns, were also analyzed for potential relationships. Bootstrapping analysis revealed that tropical air masses (moist and dry) resulted in the greatest number of migraine ED visits over the study period, whereas polar air masses led to fewer. Moist polar air masses in particular were found to correspond with the fewest number of migraine ED visits. On transitional air mass days, the number of migraine ED visits fell between those of tropical air mass days and polar air mass days. Transitional days characterized by pressure increases exhibited a greater number of migraine ED visits than days characterized by pressure decreases. However, no relationship was found between migraine ED visits and the magnitude of barometric pressure changes associated with transitional air masses.

Barometric fluctuations in wells tapping deep unconfined aquifers

USGS Publications Warehouse

Weeks, Edwin P.

1979-01-01

Water levels in wells screened only below the water table in unconfined aquifers fluctuate in response to atmospheric pressure changes. These fluctuations occur because the materials composing the unsaturated zone resist air movement and have capacity to store air with a change in pressure. Consequently, the translation of any pressure change at land surface is slowed as it moves through the unsaturated zone to the water table, but it reaches the water surface in the well instantaneously. Thus a pressure imbalance is created that results in a water level fluctuation. Barometric effects on water levels in unconfined aquifers can be computed by solution of the differential equation governing the flow of gas in the unsaturated zone subject to the appropriate boundary conditions. Solutions to this equation for two sets of boundary conditions were applied to compute water level response in a well tapping the Ogallala Formation near Lubbock, Texas from simultaneous microbarograph records. One set of computations, based on the step function unit response solution and convolution, resulted in a very good match between computed and measured water levels. A second set of computations, based on analysis of the amplitude ratios of simultaneous cyclic microbarograph and water level fluctuations, gave inconsistent results in terms of the unsaturated zone pneumatic properties but provided useful insights on the nature of unconfined-aquifer water level fluctuations.

A dental myth bites the dust--no observable relation between the incidence of dental abscess and the weather and lunar phase: an ecological study.

PubMed

Ristow, Oliver; Koerdt, Steffen; Stelzner, Ruben; Stelzner, Matthias; Johannes, Christoph; Ristow, Melanie; Hohlweg-Majert, Bettina; Pautke, Christoph

2015-02-11

Anecdotal reports assert a relationship between weather and lunar activity and the odontogenic abscess (OA) incidence, but this relationship has not been validated. Therefore, the present study investigated the relationship between oral pain caused by OA and a variety of meteorological parameters and cyclic lunar activity. The records of all dental emergency patients treated at the AllDent Zahnzentrum Emergency Unit in Munich, Germany during 2012 were retrospectively reviewed. Patients with oral pain who were diagnosed with OA and treated surgically (n = 1211) were included in the analysis. The OA incidence was correlated to daily meteorological data, biosynoptic weather analysis, and cyclic lunar activity. There was no seasonal variation in the OA incidence. None of the meteorological parameters, lunar phase, or biosynoptic weather class were significantly correlated with the OA incidence, except the mean barometric pressure, which was weakly correlated (rho = -0.204). The OA incidence showed a decreasing trend as barometric pressure increased (p < 0.001). On multiple linear regression, the barometric pressure accounted for approximately 4% of the OA incidence. There is no evidence supporting a correlation between the incidence of odontogenic abscess and the weather and lunar activities.

Falling Barometer--Failing Behavior.

ERIC Educational Resources Information Center

Scagliotta, Edward G.

1980-01-01

Observations of 127 boys with behavior problems (ages 9 to 13) were made to study the correlation between air pressure and adverse behavior in the Ss. Results showed that, with each change in barometric pressure, there was an obvious change in the Ss' behavior. (PHR)

Effectiveness of Sealed Double-Ring Infiltrometers{trademark} and effects of changes in atmospheric pressure on hydraulic conductivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

McMullin, S.R.

The Savannah River Site is currently evaluating some 40 hazardous and radioactive-waste sites for remediation. Among the remedial alternatives considered is closure using a kaolin clay cap. The hydraulic conductivity suggested by the US Environmental Protection Agency is 1.0 {times} 10{sup {minus}7} cm/sec. One instrument to measure this value is the Sealed Double-Ring Infiltrometer{trademark} (SDRI). Six SDRI were recently installed on a kaolin test cap. Test results demonstrated uniform performance of these instruments. However, the test data showed as much as an order of magnitude of variation over time. This variation is attributed to both internal structural heterogeneity and variablemore » external boundary conditions. The internal heterogeneity is caused by construction variability within a specified range of moisture and density. The external influences considered are temperature and barometric pressure. Temperature was discharged as a source of heterogeneity because of a lack of correlation with test data and a negligible impact from the range of variability. However, a direct correlation was found between changes in barometric pressure and hydraulic conductivity. This correlation is most pronounced when pressure changes occur over a short period of time. Additionally, this correlation is related to a single soil layer. When the wetting front passes into a more porous foundation layer, the correlation with pressure changes disappears. Conclusions are that the SDRI performs adequately, with good repeatability of results. The duration of test is critical to assure a statistically valid data set. Data spikes resulting from pressure changes should be identified, and professional judgment used to determine the representative hydraulic conductivity. Further evaluation is recommended to determine the impact of pressure change on the actual hydraulic conductivity.« less

Paul Bert

NASA Technical Reports Server (NTRS)

Colin, J.

1978-01-01

This biographical article on Paul Bert highlights his studies on the physiology of respiration and barometric pressure and, in particular his contributions to the understanding of hypoxia, hyperoxia and anesthesia.

On the development and benchmarking of an approach to model gas transport in fractured media with immobile water storage

NASA Astrophysics Data System (ADS)

Harp, D. R.; Ortiz, J. P.; Pandey, S.; Karra, S.; Viswanathan, H. S.; Stauffer, P. H.; Anderson, D. N.; Bradley, C. R.

2017-12-01

In unsaturated fractured media, the rate of gas transport is much greater than liquid transport in many applications (e.g., soil vapor extraction operations, methane leaks from hydraulic fracking, shallow CO2 transport from geologic sequestration operations, and later-time radionuclide gas transport from underground nuclear explosions). However, the relatively immobile pore water can inhibit or promote gas transport for soluble constituents by providing storage. In scenarios with constant pressure gradients, the gas transport will be retarded. In scenarios with reversing pressure gradients (i.e. barometric pressure variations) pore water storage can enhance gas transport by providing a ratcheting mechanism. Recognizing the computational efficiency that can be gained using a single-phase model and the necessity of considering pore water storage, we develop a Richard's solution approach that includes kinetic dissolution/volatilization of constituents. Henry's Law governs the equilibrium gaseous/aqueous phase partitioning in the approach. The approach is implemented in a development branch of the PFLOTRAN simulator. We verify the approach with analytical solutions of: (1) 1D gas diffusion, (2) 1D gas advection, (3) sinusoidal barometric pumping of a fracture, and (4) gas transport along a fracture with uniform flow and diffusive walls. We demonstrate the retardation of gas transport in cases with constant pressure gradients and the enhancement of gas transport with reversing pressure gradients. The figure presents the verification of our approach to the analytical solution of barometric pumping of a fracture from Nilson et al (1991) where the x-axis "Horizontal axis" is the distance into the matrix block from the fracture.

On the development and benchmarking of an approach to model gas transport in fractured media with immobile water storage

NASA Astrophysics Data System (ADS)

Harp, D. R.; Ortiz, J. P.; Pandey, S.; Karra, S.; Viswanathan, H. S.; Stauffer, P. H.; Anderson, D. N.; Bradley, C. R.

2016-12-01

In unsaturated fractured media, the rate of gas transport is much greater than liquid transport in many applications (e.g., soil vapor extraction operations, methane leaks from hydraulic fracking, shallow CO2 transport from geologic sequestration operations, and later-time radionuclide gas transport from underground nuclear explosions). However, the relatively immobile pore water can inhibit or promote gas transport for soluble constituents by providing storage. In scenarios with constant pressure gradients, the gas transport will be retarded. In scenarios with reversing pressure gradients (i.e. barometric pressure variations) pore water storage can enhance gas transport by providing a ratcheting mechanism. Recognizing the computational efficiency that can be gained using a single-phase model and the necessity of considering pore water storage, we develop a Richard's solution approach that includes kinetic dissolution/volatilization of constituents. Henry's Law governs the equilibrium gaseous/aqueous phase partitioning in the approach. The approach is implemented in a development branch of the PFLOTRAN simulator. We verify the approach with analytical solutions of: (1) 1D gas diffusion, (2) 1D gas advection, (3) sinusoidal barometric pumping of a fracture, and (4) gas transport along a fracture with uniform flow and diffusive walls. We demonstrate the retardation of gas transport in cases with constant pressure gradients and the enhancement of gas transport with reversing pressure gradients. The figure presents the verification of our approach to the analytical solution of barometric pumping of a fracture from Nilson et al (1991) where the x-axis "Horizontal axis" is the distance into the matrix block from the fracture.

Using Smartphone Pressure Sensors to Measure Vertical Velocities of Elevators, Stairways, and Drones

ERIC Educational Resources Information Center

Monteiro, Martín; Martí, Arturo C.

2017-01-01

We measure the vertical velocities of elevators, pedestrians climbing stairs, and drones (flying unmanned aerial vehicles), by means of smartphone pressure sensors. The barometric pressure obtained with the smartphone is related to the altitude of the device via the hydrostatic approximation. From the altitude values, vertical velocities are…

The influence of meteorological and geomagnetic factors on acute myocardial infarction and brain stroke in Moscow, Russia.

PubMed

Shaposhnikov, Dmitry; Revich, Boris; Gurfinkel, Yuri; Naumova, Elena

2014-07-01

Evidence of the impact of air temperature and pressure on cardiovascular morbidity is still quite limited and controversial, and even less is known about the potential influence of geomagnetic activity. The objective of this study was to assess impacts of air temperature, barometric pressure and geomagnetic activity on hospitalizations with myocardial infarctions and brain strokes. We studied 2,833 myocardial infarctions and 1,096 brain strokes registered in two Moscow hospitals between 1992 and 2005. Daily event rates were linked with meteorological and geomagnetic conditions, using generalized linear model with controls for day of the week, seasonal and long-term trends. The number of myocardial infarctions decreased with temperature, displayed a U-shaped relationship with pressure and variations in pressure, and increased with geomagnetic activity. The number of strokes increased with temperature, daily temperature range and geomagnetic activity. Detrimental effects on strokes of low pressure and falling pressure were observed. Relative risks of infarctions and strokes during geomagnetic storms were 1.29 (95% CI 1.19-1.40) and 1.25 (1.10-1.42), respectively. The number of strokes doubled during cold spells. The influence of barometric pressure on hospitalizations was relatively greater than the influence of geomagnetic activity, and the influence of temperature was greater than the influence of pressure. Brain strokes were more sensitive to inclement weather than myocardial infarctions. This paper provides quantitative estimates of the expected increases in hospital admissions on the worst days and can help to develop preventive health plans for cardiovascular diseases.

Monitoring Inland Storm Surge and Flooding from Hurricane Rita

USGS Publications Warehouse

McGee, Benton D.; Tollett, Roland W.; Mason, Jr., Robert R.

2006-01-01

Pressure transducers (sensors) and high-water marks were used to document the inland water levels related to storm surge generated by Hurricane Rita in southwestern Louisiana and southeastern Texas. On September 22-23, 2005, an experimental monitoring network of sensors was deployed at 33 sites over an area of about 4,000 square miles to record the timing, extent, and magnitude of inland hurricane storm surge and coastal flooding. Sensors were programmed to record date and time, temperature, and barometric or water pressure. Water pressure was corrected for changes in barometric pressure and salinity. Elevation surveys using global-positioning systems and differential levels were used to relate all storm-surge water-level data, reference marks, benchmarks, sensor measuring points, and high-water marks to the North American Vertical Datum of 1988 (NAVD 88). The resulting data indicated that storm-surge water levels over 14 feet above NAVD 88 occurred at three locations, and rates of water-level rise greater than 5 feet per hour occurred at three locations near the Louisiana coast.

Changes of pressure and humidity affect olfactory function.

PubMed

Kuehn, Michael; Welsch, Heiko; Zahnert, Thomas; Hummel, Thomas

2008-03-01

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, but not suprathreshold odor discrimination, was impaired in a hypobaric compared to a hyperbaric milieu, and thresholds were lower in humid, compared to relatively dry conditions. In conclusion, environmental conditions modulate the sense of smell, and may, consecutively, influence results from olfactory tests.

The influence of layering and barometric pumping on firn air transport in a 2-D model

NASA Astrophysics Data System (ADS)

Birner, Benjamin; Buizert, Christo; Wagner, Till J. W.; Severinghaus, Jeffrey P.

2018-06-01

Ancient air trapped in ice core bubbles has been paramount to developing our understanding of past climate and atmospheric composition. Before air bubbles become isolated in ice, the atmospheric signal is altered in the firn column by transport processes such as advection and diffusion. However, the influence of low-permeability layers and barometric pumping (driven by surface pressure variability) on firn air transport is not well understood and is not readily captured in conventional one-dimensional (1-D) firn air models. Here we present a two-dimensional (2-D) trace gas advection-diffusion-dispersion model that accounts for discontinuous horizontal layers of reduced permeability. We find that layering or barometric pumping individually yields too small a reduction in gravitational settling to match observations. In contrast, when both effects are active, the model's gravitational fractionation is suppressed as observed. Layering focuses airflows in certain regions in the 2-D model, which acts to amplify the dispersive mixing resulting from barometric pumping. Hence, the representation of both factors is needed to obtain a realistic emergence of the lock-in zone. In contrast to expectations, we find that the addition of barometric pumping in the layered 2-D model does not substantially change the differential kinetic fractionation of fast- and slow-diffusing trace gases. Like 1-D models, the 2-D model substantially underestimates the amount of differential kinetic fractionation seen in actual observations, suggesting that further subgrid-scale processes may be missing in the current generation of firn air transport models. However, we find robust scaling relationships between kinetic isotope fractionation of different noble gas isotope and elemental ratios. These relationships may be used to correct for kinetic fractionation in future high-precision ice core studies and can amount to a bias of up to 0.45 °C in noble-gas-based mean ocean temperature reconstructions at WAIS Divide, Antarctica.

Using barometric time series of the IMS infrasound network for a global analysis of thermally induced atmospheric tides

NASA Astrophysics Data System (ADS)

Hupe, Patrick; Ceranna, Lars; Pilger, Christoph

2018-04-01

The International Monitoring System (IMS) has been established to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty and comprises four technologies, one of which is infrasound. When fully established, the IMS infrasound network consists of 60 sites uniformly distributed around the globe. Besides its primary purpose of determining explosions in the atmosphere, the recorded data reveal information on other anthropogenic and natural infrasound sources. Furthermore, the almost continuous multi-year recordings of differential and absolute air pressure allow for analysing the atmospheric conditions. In this paper, spectral analysis tools are applied to derive atmospheric dynamics from barometric time series. Based on the solar atmospheric tides, a methodology for performing geographic and temporal variability analyses is presented, which is supposed to serve for upcoming studies related to atmospheric dynamics. The surplus value of using the IMS infrasound network data for such purposes is demonstrated by comparing the findings on the thermal tides with previous studies and the Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA-2), which represents the solar tides well in its surface pressure fields. Absolute air pressure recordings reveal geographical characteristics of atmospheric tides related to the solar day and even to the lunar day. We therefore claim the chosen methodology of using the IMS infrasound network to be applicable for global and temporal studies on specific atmospheric dynamics. Given the accuracy and high temporal resolution of the barometric data from the IMS infrasound network, interactions with gravity waves and planetary waves can be examined in future for refining the knowledge of atmospheric dynamics, e.g. the origin of tidal harmonics up to 9 cycles per day as found in the barometric data sets. Data assimilation in empirical models of solar tides would be a valuable application of the IMS infrasound data.

Persistence of baroreceptor control of cerebral blood flow velocity at a simulated altitude of 5000 m.

PubMed

Passino, Claudio; Cencetti, Simone; Spadacini, Giammario; Quintana, Robert; Parker, Daryl; Robergs, Robert; Appenzeller, Otto; Bernardi, Luciano

2007-09-01

To assess the effects of acute exposure to simulated high altitude on baroreflex control of mean cerebral blood flow velocity (MCFV). We compared beat-to-beat changes in RR interval, arterial blood pressure, mean MCFV (by transcranial Doppler velocimetry in the middle cerebral artery), end-tidal CO2, oxygen saturation and respiration in 19 healthy subjects at baseline (Albuquerque, 1779 m), after acute exposure to simulated high altitude in a hypobaric chamber (barometric pressure as at 5000 m) and during oxygen administration (to achieve 100% oxygen saturation) at the same barometric pressure (HOX). Baroreflex control on each signal was assessed by univariate and bivariate power spectral analysis performed on time series obtained during controlled (15 breaths/min) breathing, before and during baroreflex modulation induced by 0.1-Hz sinusoidal neck suction. At baseline, neck suction was able to induce a clear increase in low-frequency power in MCFV (P<0.001) as well as in RR and blood pressure. At high altitude, MCFV, as well as RR and blood pressure, was still able to respond to neck suction (all P<0.001), compared to controlled breathing alone, despite marked decreases in end-tidal CO2 and oxygen saturation at high altitude. A similar response was obtained at HOX. Phase delay analysis excluded a passive transmission of low-frequency oscillations from arterial pressure to cerebral circulation. During acute exposure to high altitude, cerebral blood flow is still modulated by the autonomic nervous system through the baroreflex, whose sensitivity is not affected by changes in CO2 and oxygen saturation levels.

Infrasound, Its Sources and Its Effects on Man

DTIC Science & Technology

1976-05-01

modulated by an infra - Annoyance has been broken out as a separate sonic frequency. For instance, the amplified topic because I believe that the greatest...importance is the nigh frequency response of quency sound. In general, infrasound does not the measurement system. Measurement of infra - often occur at levels...esuential for detailed analysis and changes in barometric pressure would be con- from these recordings a narrow band spectral sidered infrasonic . The

[Effect of weather on odontogenic abscesses].

PubMed

Nissen, G; Schmidseder, R

1978-11-01

An increased frequency of odontogenous abcesses was observed on certain days in the course of routine clinical practice. We therefore investigated the possibility of a statistically significant weather-related odontogenous soft-tissue purulence originating from chronic apical periodontitis. Medical reports of patients treated between 1970 and 1977 were used. Our study indicated that the frequency of odontogenous abcesses was significantly higher with cyclonic weather conditions, i.e., weather with low barometric pressure.

40 CFR 63.121 - Storage vessel provisions-alternative means of emission limitation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and... account for other emission variables such as temperature and barometric pressure, or (2) An engineering...

40 CFR 63.121 - Storage vessel provisions-alternative means of emission limitation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and... account for other emission variables such as temperature and barometric pressure, or (2) An engineering...

40 CFR 63.121 - Storage vessel provisions-alternative means of emission limitation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and... account for other emission variables such as temperature and barometric pressure, or (2) An engineering...

40 CFR 63.121 - Storage vessel provisions-alternative means of emission limitation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and... account for other emission variables such as temperature and barometric pressure, or (2) An engineering...

40 CFR 63.121 - Storage vessel provisions-alternative means of emission limitation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and... account for other emission variables such as temperature and barometric pressure, or (2) An engineering...

Archimedes and the Magdeburg Hemispheres

ERIC Educational Resources Information Center

Hayn, Carl H.

1975-01-01

Weights suspended from a lever arm separate evacuated hemispheres allowing estimation of atmospheric pressure to within five percent of the barometric reading. An illustration and a reference to von Guericke's demonstration are provided. (GH)

Effects of Barometric Fluctuations on Well Water-Level Measurements and Aquifer Test Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spane, Frank A.

1999-12-16

This report examines the effects of barometric fluctuations on well water-level measurements and evaluates adjustment and removal methods for determining areal aquifer head conditions and aquifer test analysis. Two examples of Hanford Site unconfined aquifer tests are examined that demonstrate baro-metric response analysis and illustrate the predictive/removal capabilities of various methods for well water-level and aquifer total head values. Good predictive/removal characteristics were demonstrated with best corrective results provided by multiple-regression deconvolution methods.

Altitude-induced decompression sickness

DOT National Transportation Integrated Search

2010-01-01

Decompression sickness (DCS) describes a condition characterized by a variety of symptoms resulting from exposure to low barometric pressures that cause inert gases (mainly nitrogen), normally dissolved in body fluids and tissues, to come out of phys...

Arterial blood gas reference values for sea level and an altitude of 1,400 meters.

PubMed

Crapo, R O; Jensen, R L; Hegewald, M; Tashkin, D P

1999-11-01

Blood gas measurements were collected on healthy lifetime nonsmokers at sea level (n = 96) and at an altitude of 1,400 meters (n = 243) to establish reference equations. At each study site, arterial blood samples were analyzed in duplicate on two separate blood gas analyzers and CO-oximeters. Arterial blood gas variables included Pa(O(2)), Pa(CO(2)), pH, and calculated alveolar-arterial PO(2) difference (AaPO(2)). CO-oximeter variables were Hb, COHb, MetHb, and Sa(O(2)). Subjects were 18 to 81 yr of age with 166 male and 173 female. Outlier data were excluded from multiple regression analysis, and reference equations were fitted to the data in two ways: (1) best fit using linear, squared, and cross-product terms; (2) simple equations, including only the variables that explained at least 3% of the variance. Two sets of equations were created: (1) using only the sea level data and (2) using the combined data with barometric pressure as an independent variable. Comparisons with earlier studies revealed small but significant differences; the decline in Pa(O(2)) with age at each altitude was consistent with most previous studies. At sea level, the equation that included barometric pressure predicted Pa(O(2)) slightly better than the sea level specific equation. The inclusion of barometric pressure in the equations allows better prediction of blood gas reference values at sea level and at altitudes as high as 1,400 meters.

40 CFR 63.705 - Performance test methods and procedures to determine initial compliance.

Code of Federal Regulations, 2014 CFR

2014-07-01

... per gram-mole. Pi = Barometric pressure at the time of sample analysis, millimeters mercury absolute. 760 = Reference or standard pressure, millimeters mercury absolute. 293 = Reference or standard...: ER15DE94.005 (i) The value of RSi is zero unless the owner or operator submits the following information to...

40 CFR 63.705 - Performance test methods and procedures to determine initial compliance.

Code of Federal Regulations, 2012 CFR

2012-07-01

... per gram-mole. Pi = Barometric pressure at the time of sample analysis, millimeters mercury absolute. 760 = Reference or standard pressure, millimeters mercury absolute. 293 = Reference or standard...: ER15DE94.005 (i) The value of RSi is zero unless the owner or operator submits the following information to...

40 CFR 63.705 - Performance test methods and procedures to determine initial compliance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... per gram-mole. Pi = Barometric pressure at the time of sample analysis, millimeters mercury absolute. 760 = Reference or standard pressure, millimeters mercury absolute. 293 = Reference or standard...: ER15DE94.005 (i) The value of RSi is zero unless the owner or operator submits the following information to...

40 CFR 63.705 - Performance test methods and procedures to determine initial compliance.

Code of Federal Regulations, 2013 CFR

2013-07-01

... per gram-mole. Pi = Barometric pressure at the time of sample analysis, millimeters mercury absolute. 760 = Reference or standard pressure, millimeters mercury absolute. 293 = Reference or standard...: ER15DE94.005 (i) The value of RSi is zero unless the owner or operator submits the following information to...

40 CFR 63.705 - Performance test methods and procedures to determine initial compliance.

Code of Federal Regulations, 2011 CFR

2011-07-01

... per gram-mole. Pi = Barometric pressure at the time of sample analysis, millimeters mercury absolute. 760 = Reference or standard pressure, millimeters mercury absolute. 293 = Reference or standard...: ER15DE94.005 (i) The value of RSi is zero unless the owner or operator submits the following information to...

The measurement of Eustachian tube function in a hyperbaric chamber using an ear canal microphone.

PubMed

Fischer, Hans-Georg; Koch, Andreas; Kähler, Wataru; Pohl, Michael; Pau, Hans-Wilhelm; Zehlicke, Thorsten

2016-03-01

The purpose of this study was to further the understanding of the opening of the Eustachian tube in relation to changes in barometric pressure. An ear canal microphone was used to measure the specific sounds related to tube opening and possible eardrum movements. Five subjects with normal tube function were examined in a hyperbaric chamber (up to 304 kPa). All active and passive equalization events were recorded and correlated with the subjectively perceived pressure regulation in the measured ear. The signals recorded were clear and reproducible. The acoustic analysis distinguished between the different kinds of equalization. Subjective impressions were confirmed by the recorded frequency of acoustic phenomena (clicks). During compression, the sequence of active equalization manoeuvres was in a more regular and steady pattern than during decompression, when the click sounds varied. The study established a simple technical method for analyzing the function of the Eustachian tube and provided new information about barometric pressure regulation of the middle ear.

40 CFR 91.424 - Dilute sampling procedure-CVS calibration.

Code of Federal Regulations, 2014 CFR

2014-07-01

... temperature at CVS pump inlet PTI °C ±1.11 °C Pressure depression at CVS pump inlet PPI kPa ±0.055 kPa...) Reset the restrictor valve to a more restricted condition in an increment of pump inlet depression that...=Absolute pump inlet pressure, kPa. =PP−PPI Where: PP=barometric pressure, kPa. PPI=Pump inlet depression, k...

40 CFR 91.424 - Dilute sampling procedure-CVS calibration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... temperature at CVS pump inlet PTI °C ±1.11 °C Pressure depression at CVS pump inlet PPI kPa ±0.055 kPa...) Reset the restrictor valve to a more restricted condition in an increment of pump inlet depression that...=Absolute pump inlet pressure, kPa. =PP−PPI Where: PP=barometric pressure, kPa. PPI=Pump inlet depression, k...

40 CFR 91.424 - Dilute sampling procedure-CVS calibration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... temperature at CVS pump inlet PTI °C ±1.11 °C Pressure depression at CVS pump inlet PPI kPa ±0.055 kPa...) Reset the restrictor valve to a more restricted condition in an increment of pump inlet depression that...=Absolute pump inlet pressure, kPa. =PP−PPI Where: PP=barometric pressure, kPa. PPI=Pump inlet depression, k...

40 CFR 91.424 - Dilute sampling procedure-CVS calibration.

Code of Federal Regulations, 2012 CFR

2012-07-01

... temperature at CVS pump inlet PTI °C ±1.11 °C Pressure depression at CVS pump inlet PPI kPa ±0.055 kPa...) Reset the restrictor valve to a more restricted condition in an increment of pump inlet depression that...=Absolute pump inlet pressure, kPa. =PP−PPI Where: PP=barometric pressure, kPa. PPI=Pump inlet depression, k...

40 CFR 91.424 - Dilute sampling procedure-CVS calibration.

Code of Federal Regulations, 2013 CFR

2013-07-01

... temperature at CVS pump inlet PTI °C ±1.11 °C Pressure depression at CVS pump inlet PPI kPa ±0.055 kPa...) Reset the restrictor valve to a more restricted condition in an increment of pump inlet depression that...=Absolute pump inlet pressure, kPa. =PP−PPI Where: PP=barometric pressure, kPa. PPI=Pump inlet depression, k...

Aviation dentistry: current concepts and practice.

PubMed

Zadik, Y

2009-01-10

With the growing number of air passengers, flight attendants, leisure pilots as well as military and airline pilots, dentists may increasingly encounter flight-related oral conditions requiring treatment. Moreover, dentists should prevent the creation of in-flight hazards when treating aircrew members. The aim of this article is to introduce the concepts of aviation (aerospace) medicine and dentistry. Data were gathered to cover the following issues: head and facial barotraumas (barotrauma-related headache, external otitic barotrauma, barosinusitis and barotitis-media), dental barotrauma (barometric pressure-related tooth injury), barodontalgia (barometric pressure-related oro-dental pain), and dental care for aircrews. Special considerations have to be made when planning restorative, endodontic, prosthodontic and surgical treatment to an aircrew patient. This article supplies the dental practitioner with some diagnostic tools as well as treatment guidelines. Principles of prevention, periodic examination, dental-related flight restriction (grounding) and dental documentation (for forensic purposes) are described as well.

Differential barometric-based positioning technique for indoor elevation measurement in IoT medical applications.

PubMed

Wang, Hua; Wen, Yingyou; Zhao, Dazhe

2017-07-20

Medical applications have begun to benefit from Internet of Things (IoT) technology through the introduction of wearable devices. Several medical applications require accurate patient location as various changes affect pressure parameters inside the body. This study aims to develop a system to measure indoor altitude for IoT medical applications. We propose a differential barometric-based positioning system to estimate the altitude between a reference sensor and a localizing sensor connected to the human body. The differential barometric altimetry model is introduced to estimate indoor elevations and eliminate environmental artifacts. In addition, a Gaussian filter processing is adopted to remove noise from the elevation measurements. The proposed system is then investigated through extensive experiments, using various evaluation criteria. The results indicate that the proposed system yielded good accuracy with reduced implementation complexity and fewer costs. The proposed system is resilient compared to other indoor localization approaches, even when numerous environmental artifacts in indoor environments are present.

Effect of ambient pressure variation on closed loop gas system for India based Neutrino Observatory (INO)

NASA Astrophysics Data System (ADS)

Satyanarayana, B.; Majumder, G.; Mondal, N. K.; Kalmani, S. D.; Shinde, R. R.; Joshi, A.

2014-10-01

Pilot unit of a closed loop gas mixing and distribution system for the INO project was designed and is being operated with 1.8meters × 1.9meters RPCs for about two years. A number of studies on controlling the flow and optimisation of the gas mixture through the RPC stack were carried out during this period. The gas system essentially measures and attempts to maintain absolute pressure inside the RPC gas volume. During typical Mumbai monsoon seasons, the barometric pressure changes rather rapidly, due to which the gas system fails to maintain the set differential pressure between the ambience and the RPC gas volume. As the safety bubblers on the RPC gas input lines are set to work on fixed pressure differentials, the ambient pressure changes lead to either venting out and thus wasting gas through safety bubblers or over pressuring the RPCs gas volume and thus degrading its performance. The above problem also leads to gas mixture contamination through minute leaks in gas gap. The problem stated above was solved by including the ambient barometric pressure as an input parameter in the closed loop. Using this, it is now possible to maintain any set differential pressure between the ambience and RPC gas volumes between 0 to 20mm of water column, thus always ensuring a positive pressure inside the RPC gas volume with respect to the ambience. This has resulted in improved performance of the gas system by maintaining the constant gas flow and reducing the gas toping up frequency. In this paper, we will highlight the design features and improvements of the closed loop gas system. We will present some of the performance studies and considerations for scaling up the system to be used with the engineering module and then followed by Iron Calorimeter detector (ICAL), which is designed to deploy about 30,000 RPCs of 1.8meters × 1.9 meters in area.

Assessment of a landfill methane emission screening method using an unmanned aerial vehicle mounted thermal infrared camera - A field study.

PubMed

Fjelsted, L; Christensen, A G; Larsen, J E; Kjeldsen, P; Scheutz, C

2018-05-28

An unmanned aerial vehicle (UAV)-mounted thermal infrared (TIR) camera's ability to delineate landfill gas (LFG) emission hotspots was evaluated in a field test at two Danish landfills (Hedeland landfill and Audebo landfill). At both sites, a test area of 100 m 2 was established and divided into about 100 measuring points. The relationship between LFG emissions and soil surface temperatures were investigated through four to five measuring campaigns, in order to cover different atmospheric conditions along with increasing, decreasing and stable barometric pressure. For each measuring campaign, a TIR image of the test area was obtained followed by the measurement of methane (CH 4 ) and carbon dioxide (CO 2 ) emissions at each measuring point, using a static flux chamber. At the same time, soil temperatures measured on the surface, at 5 cm and 10 cm depths, were registered. At the Hedeland landfill, no relationship was found between LFG emissions and surface temperatures. In addition, CH 4 emissions were very limited, on average 0.92-4.52 g CH 4  m -2  d -1 , and only measureable on the two days with decreasing barometric pressure. TIR images from Hedeland did not show any significant temperature differences in the test area. At the Audebo landfill, an area with slightly higher surface temperatures was found in the TIR images, and the same pattern with slightly higher temperatures was found at a depth of 10 cm. The main LFG emissions were found in the area with the higher surface temperatures. LFG emissions at Audebo were influenced significantly by changes in barometric pressure, and the average CH 4 emissions varied between 111 g m -2  d -1 and 314 g m -2  d -1 , depending on whether the barometric pressure gradient had increased or decreased, respectively. The temperature differences observed in the TIR images from both landfills were limited to between 0.7 °C and 1.2 °C. The minimum observable CH 4 emission for the TIR camera to identify an emission hotspot was 150 g CH 4  m -2  d -1 from an area of more than 1 m 2 . Copyright © 2018 Elsevier Ltd. All rights reserved.

40 CFR 90.424 - Dilute sampling procedures-CVS calibration.

Code of Federal Regulations, 2012 CFR

2012-07-01

.... Air temperature at CVS pump inlet PTI °C ±1.11 °C. Pressure depression at CVS pump inlet PPI kPa ±0... pump inlet depression that will yield a minimum of six data points for the total calibration. Allow the...: PB = barometric pressure, kPa PPI = Pump inlet depression, kPa. (iii) The correlation function at...

40 CFR 90.424 - Dilute sampling procedures-CVS calibration.

Code of Federal Regulations, 2014 CFR

2014-07-01

.... Air temperature at CVS pump inlet PTI °C ±1.11 °C. Pressure depression at CVS pump inlet PPI kPa ±0... pump inlet depression that will yield a minimum of six data points for the total calibration. Allow the...: PB = barometric pressure, kPa PPI = Pump inlet depression, kPa. (iii) The correlation function at...

40 CFR 90.424 - Dilute sampling procedures-CVS calibration.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... Air temperature at CVS pump inlet PTI °C ±1.11 °C. Pressure depression at CVS pump inlet PPI kPa ±0... pump inlet depression that will yield a minimum of six data points for the total calibration. Allow the...: PB = barometric pressure, kPa PPI = Pump inlet depression, kPa. (iii) The correlation function at...

40 CFR 90.424 - Dilute sampling procedures-CVS calibration.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... Air temperature at CVS pump inlet PTI °C ±1.11 °C. Pressure depression at CVS pump inlet PPI kPa ±0... pump inlet depression that will yield a minimum of six data points for the total calibration. Allow the...: PB = barometric pressure, kPa PPI = Pump inlet depression, kPa. (iii) The correlation function at...

40 CFR 90.424 - Dilute sampling procedures-CVS calibration.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... Air temperature at CVS pump inlet PTI °C ±1.11 °C. Pressure depression at CVS pump inlet PPI kPa ±0... pump inlet depression that will yield a minimum of six data points for the total calibration. Allow the...: PB = barometric pressure, kPa PPI = Pump inlet depression, kPa. (iii) The correlation function at...

Monitoring Inland Storm Surge and Flooding from Hurricane Ike in Texas and Louisiana, September 2008

USGS Publications Warehouse

East, Jeffery W.; Turco, Michael J.; Mason, Jr., Robert R.

2008-01-01

The U.S. Geological Survey (USGS) deployed a temporary monitoring network of 117 pressure transducers (sensors) at 65 sites over an area of about 5,000 square miles to record the timing, areal extent, and magnitude of inland hurricane storm surge and coastal flooding generated by Hurricane Ike, which struck southeastern Texas and southwestern Louisiana September 12-13, 2008. Fifty-six sites were in Texas and nine were in Louisiana. Sites were categorized as surge, riverine, or beach/wave on the basis of proximity to the Gulf Coast. One-hundred five sensors from 59 sites (fig. 1) were recovered; 12 sensors from six sites either were lost during the storm or were not retrieved. All 59 sites (41 surge, 10 riverine, 8 beach/wave) had sensors to record water pressure (fig. 2), which is expressed as water level in feet above North American Vertical Datum of 1988 (NAVD88), and 46 sites had an additional sensor to record barometric pressure, expressed in pounds per square inch. Figure 3 shows an example of water level and barometric pressure over time recorded by sensors during the storm.

The influence of weather on Golden Eagle migration in northwestern Montana

USGS Publications Warehouse

Yates, R.E.; McClelland, B.R.; Mcclelland, P.T.; Key, C.H.; Bennetts, R.E.

2001-01-01

We analyzed the influence of 17 weather factors on migrating Golden Eagles (Aquila chrysaetos) near the Continental Divide in Glacier National Park, Montana, U.S.A. Local weather measurements were recorded at automated stations on the flanks of two peaks within the migration path. During a total of 506 hr of observation, the yearly number of Golden Eagles in autumn counts (1994-96) averaged 1973; spring counts (1995 and 1996) averaged 605 eagles. Mean passage rates (eagles/hr) were 16.5 in autumn and 8.2 in spring. Maximum rates were 137 in autumn and 67 in spring. Using generalized linear modeling, we tested for the effects of weather factors on the number of eagles counted. In the autumn model, the number of eagles increased with increasing air temperature, rising barometric pressure, decreasing relative humidity, and interactions among those factors. In the spring model, the number of eagles increased with increasing wind speed, barometric pressure, and the interaction between these factors. Our data suggest that a complex interaction among weather factors influenced the number of eagles passing on a given day. We hypothesize that in complex landscapes with high topographic relief, such as Glacier National Park, numerous weather factors produce different daily combinations to which migrating eagles respond opportunistically. ?? 2001 The Raptor Research Foundation, Inc.

Aeronautic Instruments. Section II : Altitude Instruments

NASA Technical Reports Server (NTRS)

Mears, A H; Henrickson, H B; Brombacher, W G

1923-01-01

This report is Section two of a series of reports on aeronautic instruments (Technical Report nos. 125 to 132, inclusive). This section discusses briefly barometric altitude determinations, and describes in detail the principal types of altimeters and barographs used in aeronautics during the recent war. This is followed by a discussion of performance requirements for such instruments and an account of the methods of testing developed by the Bureau of Standards. The report concludes with a brief account of the results of recent investigations. For accurate measurements of altitude, reference must also be made to thermometer readings of atmospheric temperature, since the altitude is not fixed by atmospheric pressure alone. This matter is discussed in connection with barometric altitude determination.

A model of oscillatory transport in granular soils, with application to barometric pumping and earth tides.

PubMed

Neeper, D A

2001-04-01

A simple algebraic model is proposed to estimate the transport of a volatile or soluble chemical caused by oscillatory flow of fluid in a porous medium. The model is applied to the barometric pumping of vapors in the vadose zone, and to the transport of dissolved species by earth tides in an aquifer. In the model, the fluid moves sinusoidally with time in the porosity of the soil. The chemical concentration in the mobile fluid is considered to equilibrate with the concentration in the surrounding matrix according to a characteristic time governed by diffusion, sorption, or other rate processes. The model provides a closed form solution, to which barometric pressure data are applied in an example of pore gas motion in the vadose zone. The model predicts that the additional diffusivity due barometric pumping in an unfractured vadose zone would be comparable to the diffusivity in stagnant pore gas if the equilibration time is 1 day or longer. Water motion due to the M2 lunar tide is examined as an example of oscillatory transport in an aquifer. It is shown that the tidal motion of the water in an aquifer might significantly increase the vertical diffusivity of dissolved species when compared to diffusion in an absolutely stagnant aquifer, but the hydrodynamic dispersivity due to tidal motion or gravitational flow would probably exceed the diffusivity due to oscillatory advection.

Pollution Permanent Monitoring PANEL--2013 Annual Report

NASA Astrophysics Data System (ADS)

Everett, Lorne G.

2014-07-01

The following sections are included: * POLLUTION PANEL ACTIVITIES 2013 * NATIONAL ACADEMY OF SCIENCES 2013 * MTBE NEW HAMPSHIRE LITIGATION--APRIL 12, 2013 * ALTERNATIVES FOR MANAGING THE NATION's COMPLEX CONTAMINATED GROUNDWATER SITES--NATIONAL ACADEMY OF SCIENCES, 2013 * HUMAN HEALTH EFFECTS OF TRICHLOROETHYLENE: KEY FINDINGS AND SCIENTIFIC ISSUES. MARCH 1, 2013 REVIEWS * BAROMETRIC PRESSURE DRIVES SOIL-GAS CONCENTRATIONS * WATER RESOURCES--TERRORISM TARGETS * WITH A LITTLE INGENUITY THE PROBLEM IS NOT INSOLUBLE * HIGH RISE BUILDINGS * TERRORIST MATERIAL MAY DESTROY WATER TRANSMISSION INFRASTRUCTURE * WATER THREAT CONCLUSIONS * MULTINATIONAL REPOSITORIES

Asthma and climatic conditions: experience from Bermuda, an isolated island community.

PubMed Central

Carey, M J; Cordon, I

1986-01-01

A retrospective study of patients attending the emergency department with acute asthma was performed in Bermuda. Climatic data (barometric pressure, rainfall, humidity, and wind strength and direction) were obtained and compared with frequency of exacerbations of asthma. Three factors--namely, relative humidity, average daily temperature, and northeasterly winds--were found to be related to worsening asthma. Owing to Bermuda's lack of pollution and aeroallergens it was thought that these weather parameters had a direct effect on the asthmatic population. PMID:3094682

Tidal impact on geophysical fields registed in GPO "Mikhnevo" area

NASA Astrophysics Data System (ADS)

Vinogradov, Evgeny; Besedina, Alina; Gorbunova, Ella

2013-04-01

Geophysical observatory "Mikhnevo" is situated in the centre of Russian Plate and characterized with stable response to lunisolar tides. Since February 2008, regular precision measurements of groundwater level are carried out in a measurement well synchronously with atmospheric pressure measurements (sampling interval is 1 s, the measurement accuracy is 0.1 mm for the level and 0.1 gPa for atmospheric pressure). According to the results of hydrogeological sampling, the pressure head in the aquifer under study is 8.1 m, its transmissivity is 3.0 m2/day, hydraulic conductivity was 0.13 m/day, the pressure conductivity factor and elastic water yield are 1.3 × 104 m2/day and 2.3 × 10-4, respectively. Using flow measurements and telemetry of the open part of bore hole, major intervals of water inflow were detected at depths of 92-94 m and 99-100 m. Rock transmissivity in the fissure-conducting zone increases to 5.0 m2/day. Based on tidal component analysis in the filtered hydrogeological data, five main kinds of tidal waves were extracted (?1, ?2, Q1, ?1 and 2). STS-2 and KSESh-R seismometers registration range extension made it possible to extract tidal waves from Z-component of ground displacement. Similar methodology of data processing was used for tides analysis in hydrogeological, seismic and barometric data. It should be noted that barometric component extracted from water level variations can, in some cases, lead to misrepresentation of the data in frequency range under consideration. That is why two variants of data were analysed - with included and excluded barometric component. To extract tides from water level variations, long-period and barometric components were excluded from original precise monitoring datum. Data series obtained in this way were used for monthly spectrum realization, which, in turn, allowed finding out amplitudes of main tidal waves ?1, ?1 and 2. The most significant luni-solar ?1 wave annual variations cycle correlates with hydraulic head. Maximum amplitudes of ?1 wave for the whole 4 year observation period are observed then the ground-water level is high. Variation range of ?1 wave amplitude is stable and reaches 2.9 mm per year. Most significant variations take place in spring-summer period. Main lunar waves amplitude variations do not exceed 1.1 mm. The phase shift increase between luni-solar tides response in seismic and hydrogeological data was found. Diurnal O1 wave variations analysis should be done with barometric component excluded datum because of amplitude difference. During period under consideration M2 and K1 waves amplitudes are comparable and about 4.1 mm, O1 amplitude is on it minimum about 3.7 mm. Maximum diurnal and semi-diurnal wave amplitudes of water level variations confine with minimum values of luni-solar attraction. On the contrary on the same periods we can see decrease of ground displacement amplitudes as a result of tidal forces. Main tidal waves were extracted from atmospheric pressure datum too. Luni-solar K1 wave has the most amplitude there and exceeds O1 and M2 values 5-7 times.

2 Aspirin and Bedrest Won't Help!

ERIC Educational Resources Information Center

Scagliotta, Edward G.

1983-01-01

The author contends that falling barometric pressure hampers the flow of blood throughout the nervous system, thus encouraging maladaptive behavior in some neurologically impaired children. Among guidelines offered are to create a calm environment and to check the barometer frequently during the day. (CL)

Seasonal variation in the incidence of preeclampsia and eclampsia in tropical climatic conditions.

PubMed

Subramaniam, Vidya

2007-10-15

Observational studies have demonstrated various correlations between hypertensive disorders of pregnancy and different weather parameters. We aim to study if a correlation exists between the incidence of eclampsia and pre-eclampsia and various weather parameters in the tropical coastal city of Mumbai which has the distinction of having relatively uniform meteorological variables all throughout the year, except for the monsoon season. We retrospectively analysed data from a large maternity centre in Mumbai, India over a period of 36 months from March 1993 to February 1996, recording the incidence of preeclampsia and eclampsia. Meteorological data was acquired from the regional meteorological centre recording the monthly average temperature, humidity, barometric pressure and rainfall during the study period. Study period was then divided into two climate conditions: monsoon season (June to August) and dry season September to May. The incidence of preeclampsia and eclampsia and the meteorological differences between the two seasons were compared. Over a 36-month period, a total of 29562 deliveries were recorded, of which 1238 patients developed preeclampsia (4.18%) and 34 developed eclampsia (0.11%). The incidence of preeclampsia did not differ between the monsoon and the dry season (4.3% vs. 4.15%, p = 0.5). The incidence of eclampsia was significantly higher in the monsoon (0.2% vs. 0.08%, p = 0.01). The monsoon was significantly cooler (median maximum temperature 30.7 degrees C vs. 32.3 degrees C, p = 0.01), more humid (median relative humidity 85% vs. 70%, p = 0.0008), and received higher rainfall (median 504.9 mm vs. 0.3 mm, p = 0.0002) than the rest of the year. The median barometric pressure (1005 mb) during the monsoon season was significantly lower than the rest of the year (1012 mb, p < 0.0001). In the tropical climate of Mumbai, the incidence of eclampsia is significantly higher in monsoon, when the weather is cooler and humid with a lower barometric pressure than the rest of the year. This effect is not seen with preeclampsia. This strengthens the association of low temperature and high humidity with triggering of eclampsia.

Selected meteorological data for an arid site near Beatty, Nye County, Nevada, calendar years 1990 and 1991

USGS Publications Warehouse

Wood, James L.; Andraski, Brian J.

1995-01-01

Selected meteorological data were collected at a study site adjacent to a low-level radioactive-waste burial facility near Beatty, Nevada, for calendar years 1990 and 1991. Data were collected in support of ongoing studies to estimate the potential for downward movement of radionuclides into the unsaturated sediments beneath waste-burial trenches at the facility. The data include air temperature, relative humidity, vapor pressure, incident solar radiation, windspeed, wind direction, barometric pressure, and precipitation. The data are summarized in tables and graphs.Instrumentation used at the site is discussed. The discussion includes the type, reported accuracy, and mounting height of each sensor.In 1990, the average hourly air temperatures ranged from -16.2 degrees Celsius, in December, to 44.2 degrees Celsius, in July. Hourly averaged relative humidity ranged from 6 percent to more than 90 percent. Hourly vapor pressures ranged from 0.08 to 1.84 kilopascals. Daily maximum incident solar radiation values ranged from 192 to 1,028 watts per square meter. Daily mean windspeed ranged from less than 1 to 8.7 meters per second. Wind direction was primarily from the northwest in fall, winter, and spring and varied from southeast, southwest, or northwest during the summer. Hourly barometric pressures ranged from 99.47 to 103.12 kilopascals. Total precipitation for 1990 was 32.4 millimeters; almost 45 percent was in September.In 1991, the average hourly air temperatures ranged from -9.2 degrees Celsius, in January, to 43.7 degrees Celsius, in July. Hourly averaged relative humidity ranged from 3 percent to more than 95 percent. Hourly vapor pressures ranged from 0.07 to 2.22 kilopascals. Daily maximum incident solar radiation values ranged from 143 to 1,041 watts per square meter. Daily mean windspeed ranged from 1.2 to 8.4 meters per second. Wind direction was primarily from the northwest in fall, winter, and spring and varied from southeast, southwest, or northwest during the summer. Hourly barometric pressures ranged from 99.52 to 103.40 kilopascals. Total precipitation for 1991 was 103.6 millimeters; almost 60 percent was in March.

Laser barometer

DOEpatents

Abercrombie, Kevin R.; Shiels, David; Rash, Tim

2001-02-06

A pressure measuring instrument that utilizes the change of the refractive index of a gas as a function of pressure and the coherent nature of a laser light to determine the barometric pressure within an environment. As the gas pressure in a closed environment varies, the index of refraction of the gas changes. The amount of change is a function of the gas pressure. By illuminating the gas with a laser light source, causing the wavelength of the light to change, pressure can be quantified by measuring the shift in fringes (alternating light and dark bands produced when coherent light is mixed) in an interferometer.

20 CFR Appendix B to Part 718 - Standards for Administration and Interpretation of Pulmonary Function Tests. Tables B1, B2, B3...

Code of Federal Regulations, 2013 CFR

2013-04-01

... user of the instrument must have a means of correcting volumes to body temperature saturated with water vapor (BTPS) under conditions of varying ambient spirometer temperatures and barometric pressures. (v...

20 CFR Appendix B to Part 718 - Standards for Administration and Interpretation of Pulmonary Function Tests. Tables B1, B2, B3...

Code of Federal Regulations, 2014 CFR

2014-04-01

... user of the instrument must have a means of correcting volumes to body temperature saturated with water vapor (BTPS) under conditions of varying ambient spirometer temperatures and barometric pressures. (v...

20 CFR Appendix B to Part 718 - Standards for Administration and Interpretation of Pulmonary Function Tests. Tables B1, B2, B3...

Code of Federal Regulations, 2012 CFR

2012-04-01

... user of the instrument must have a means of correcting volumes to body temperature saturated with water vapor (BTPS) under conditions of varying ambient spirometer temperatures and barometric pressures. (v...

Weather, Climate, and You.

ERIC Educational Resources Information Center

Blai, Boris, Jr.

Information from the American Institute of Medical Climatologists on human responses to weather and climatic conditions, including clouds, winds, humidity, barometric pressure, heat, cold, and other variables that may exert a pervasive impact on health, behavior, disposition, and the level of efficiency with which individuals function is reviewed.…

Race Factors Affecting Performance Times in Elite Long-Track Speed Skating.

PubMed

Noordhof, Dionne A; Mulder, Roy C; de Koning, Jos J; Hopkins, Will G

2016-05-01

Analysis of sport performance can provide effects of environmental and other venue-specific factors in addition to estimates of within-athlete variability between competitions, which determines smallest worthwhile effects. To analyze elite long-track speed-skating events. Log-transformed performance times were analyzed with a mixed linear model that estimated percentage mean effects for altitude, barometric pressure, type of rink, and competition importance. In addition, coefficients of variation representing residual venue-related differences and within-athlete variability between races within clusters spanning ~8 d were determined. Effects and variability were assessed with magnitude-based inference. A 1000-m increase in altitude resulted in very large mean performance improvements of 2.8% in juniors and 2.1% in seniors. An increase in barometric pressure of 100 hPa resulted in a moderate reduction in performance of 1.1% for juniors but an unclear effect for seniors. Only juniors competed at open rinks, resulting in a very large reduction in performance of 3.4%. Juniors and seniors showed small performance improvements (0.4% and 0.3%) at the more important competitions. After accounting for these effects, residual venue-related variability was still moderate to large. The within-athlete within-cluster race-to-race variability was 0.3-1.3%, with a small difference in variability between male (0.8%) and female juniors (1.0%) and no difference between male and female seniors (both 0.6%). The variability in performance times of skaters is similar to that of athletes in other sports in which air or water resistance limits speed. A performance enhancement of 0.1-0.4% by top-10 athletes is necessary to increase medal-winning chances by 10%.

A time-series analysis of any short-term effects of meteorological and air pollution factors on preterm births in London, UK.

PubMed

Lee, Sue J; Hajat, Shakoor; Steer, Philip J; Filippi, Veronique

2008-02-01

Although much is known about the incidence and burden of preterm birth, its biological mechanisms are not well understood. While several studies have suggested that high levels of air pollution or exposure to particular climatic factors may be associated with an increased risk of preterm birth, other studies do not support such an association. To determine whether exposure to various environmental factors place a large London-based population at higher risk for preterm birth, we analyzed 482,568 births that occurred between 1988 and 2000 from the St. Mary's Maternity Information System database. Using an ecological study design, any short-term associations between preterm birth and various environmental factors were investigated using time-series regression techniques. Environmental exposures included air pollution (ambient ozone and PM(10)) and climatic factors (temperature, rainfall, sunshine, relative humidity, barometric pressure, and largest drop in barometric pressure). In addition to exposure on the day of birth, cumulative exposure up to 1 week before birth was investigated. The risk of preterm birth did not increase with exposure to the levels of ambient air pollution or meteorological factors experienced by this population. Cumulative exposure from 0 to 6 days before birth also did not show any significant effect on the risk of preterm birth. This large study, covering 13 years, suggests that there is no association between preterm births and recent exposure to ambient air pollution or recent changes in the weather.

Dispersion in deep polar firn driven by synoptic-scale surface pressure variability

NASA Astrophysics Data System (ADS)

Buizert, Christo; Severinghaus, Jeffrey P.

2016-09-01

Commonly, three mechanisms of firn air transport are distinguished: molecular diffusion, advection, and near-surface convective mixing. Here we identify and describe a fourth mechanism, namely dispersion driven by synoptic-scale surface pressure variability (or barometric pumping). We use published gas chromatography experiments on firn samples to derive the along-flow dispersivity of firn, and combine this dispersivity with a dynamical air pressure propagation model forced by surface air pressure time series to estimate the magnitude of dispersive mixing in the firn. We show that dispersion dominates mixing within the firn lock-in zone. Trace gas concentrations measured in firn air samples from various polar sites confirm that dispersive mixing occurs. Including dispersive mixing in a firn air transport model suggests that our theoretical estimates have the correct order of magnitude, yet may overestimate the true dispersion. We further show that strong barometric pumping, such as at the Law Dome site, may reduce the gravitational enrichment of δ15N-N2 and other tracers below gravitational equilibrium, questioning the traditional definition of the lock-in depth as the depth where δ15N enrichment ceases. Last, we propose that 86Kr excess may act as a proxy for past synoptic activity (or paleo-storminess) at the site.

Fire-related medical science

NASA Technical Reports Server (NTRS)

Knight, Douglas R.

1987-01-01

Spacecraft fire safety may be improved by the use of a fire-retardant atmosphere in occupied spaces. Low concentrations of oxygen can protect humans from fire damage by reducing the rate and spread of combustion, but care must be taken to avoid the hypoxic effects of oxygen-lean atmospheres. Crews can live and work in 11 percent oxygen if barometric pressure were adjusted to maintain the partial pressure of oxygen above 16 kPa. Eleven percent oxygen should prevent most types of fires, since 15 percent oxygen retards the combustion of paper and 13 percent oxygen extinguishes pentane flames. Test results indicate that seated humans can perform mental tasks in atmospheres containing 11.5 percent oxygen. Although this strategy of fire safety is under consideration for submarines, it could be adapted to spacecraft once operational procedures define a maximum hyperbaric pressure and fire research defines the effects of reduced oxygen concentrations on combustion in low gravity environments.

Meteorological Variables and Behavior of Learners with Autism: An Examination of Possible Relationships

ERIC Educational Resources Information Center

VanBuskirk, Sabrina E.; Simpson, Richard L.

2013-01-01

For this study, we collected classroom behavioral data for three children with autism relative to daily meteorological conditions. Meteorological data, including barometric pressure, humidity, outdoor temperature, and moon illumination, were obtained from the National Weather Service. Relationships between children's individual target behaviors…

40 CFR 90.405 - Recorded information.

Code of Federal Regulations, 2014 CFR

2014-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... applicable. (e) Test data; post-test. (1) Recorder chart or equivalent. Identify the hang-up check. (2...). (4) Barometric pressure, post-test segment. [60 FR 34598, July 13, 1995, as amended at 70 FR 40449...

40 CFR 90.405 - Recorded information.

Code of Federal Regulations, 2010 CFR

2010-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... applicable. (e) Test data; post-test. (1) Recorder chart or equivalent. Identify the hang-up check. (2...). (4) Barometric pressure, post-test segment. [60 FR 34598, July 13, 1995, as amended at 70 FR 40449...

40 CFR 90.405 - Recorded information.

Code of Federal Regulations, 2011 CFR

2011-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... applicable. (e) Test data; post-test. (1) Recorder chart or equivalent. Identify the hang-up check. (2...). (4) Barometric pressure, post-test segment. [60 FR 34598, July 13, 1995, as amended at 70 FR 40449...

40 CFR 90.405 - Recorded information.

Code of Federal Regulations, 2013 CFR

2013-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... applicable. (e) Test data; post-test. (1) Recorder chart or equivalent. Identify the hang-up check. (2...). (4) Barometric pressure, post-test segment. [60 FR 34598, July 13, 1995, as amended at 70 FR 40449...

40 CFR 90.405 - Recorded information.

Code of Federal Regulations, 2012 CFR

2012-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... applicable. (e) Test data; post-test. (1) Recorder chart or equivalent. Identify the hang-up check. (2...). (4) Barometric pressure, post-test segment. [60 FR 34598, July 13, 1995, as amended at 70 FR 40449...

40 CFR 86.1542 - Information required.

Code of Federal Regulations, 2011 CFR

2011-07-01

... required: (1) Date and time of day. (2) Test number. (3) Engine intake air or test cell temperature. (4) Barometric pressure. Note: A central laboratory barometer may be used: Provided, That individual test cell... location. (5) Engine intake or test cell and CVS dilution air humidity. (6) Curb idle speed during the test...

40 CFR 86.1542 - Information required.

Code of Federal Regulations, 2012 CFR

2012-07-01

... required: (1) Date and time of day. (2) Test number. (3) Engine intake air or test cell temperature. (4) Barometric pressure. Note: A central laboratory barometer may be used: Provided, That individual test cell... location. (5) Engine intake or test cell and CVS dilution air humidity. (6) Curb idle speed during the test...

40 CFR 205.54-1 - Low speed sound emission test procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... beyond the permissible end zone, unload the vehicle and/or increase the approach rpm in 100 rpm... rpm beyond the permissible end zone, unload the vehicle and/or increase the approach rpm in 100 rpm... example, temperature, humidity, and barometric pressure). (ii) Proper signal levels, terminat-ing...

Terminal Information Processing System (TIPS) Consolidated CAB Display (CCD) Comparative Analysis.

DTIC Science & Technology

1982-04-01

Barometric pressure 3. Center field wind speed, direction and gusts 4. Runway visual range 5. Low-level wind shear 6. Vortex advisory 7. Runway equipment...PASSWORD Command (standard user) u. PAUSE Command (standard user) v. PMSG Command (standard user) w. PPD Command (standard user) x. PURGE Command (standard

40 CFR 63.1064 - Alternative means of emission limitation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Standards, Chapter 19, Section 3, Part A, Wind Tunnel Test Method for the Measurement of Deck-Fitting Loss... limitation. 63.1064 Section 63.1064 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... as wind, temperature, and barometric pressure. Test methods that can be used to perform the testing...

40 CFR 63.1064 - Alternative means of emission limitation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Standards, Chapter 19, Section 3, Part A, Wind Tunnel Test Method for the Measurement of Deck-Fitting Loss... limitation. 63.1064 Section 63.1064 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... as wind, temperature, and barometric pressure. Test methods that can be used to perform the testing...

40 CFR 63.1064 - Alternative means of emission limitation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Standards, Chapter 19, Section 3, Part A, Wind Tunnel Test Method for the Measurement of Deck-Fitting Loss... limitation. 63.1064 Section 63.1064 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... as wind, temperature, and barometric pressure. Test methods that can be used to perform the testing...

40 CFR 63.1064 - Alternative means of emission limitation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Standards, Chapter 19, Section 3, Part A, Wind Tunnel Test Method for the Measurement of Deck-Fitting Loss... limitation. 63.1064 Section 63.1064 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... as wind, temperature, and barometric pressure. Test methods that can be used to perform the testing...

40 CFR 63.1064 - Alternative means of emission limitation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Standards, Chapter 19, Section 3, Part A, Wind Tunnel Test Method for the Measurement of Deck-Fitting Loss... limitation. 63.1064 Section 63.1064 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... as wind, temperature, and barometric pressure. Test methods that can be used to perform the testing...

40 CFR 63.137 - Process wastewater provisions-oil-water separators.

Code of Federal Regulations, 2010 CFR

2010-07-01

... separators. 63.137 Section 63.137 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... for other emission variables such as temperature and barometric pressure, or (ii) An engineering...)(1) and the schedule specified in paragraphs (c)(1) and (c)(2) of this section. (1) Measurement of...

Is suicide mortality associated with meteorological and socio-economic factors? An ecological study in a city in Taiwan with a high suicide rate.

PubMed

Wu, Ya Wen; Chen, Chih Ken; Wang, Liang Jen

2014-06-01

Keelung City has the highest suicide rate in Taiwan. This study aimed to determine whether meteorological and socio-economic factors are associated with suicide mortality in Keelung City, by gender and by means of suicide. Data on suicides between January 2006 and December 2010 were provided by the Department of Health, Keelung City Government. The suicide victims were categorized into non-violent and violent groups, based on the International Classification of Disease, Ninth Revision. Meteorological data were obtained from the Central Weather Bureau of Taiwan. Socio-economic data were gathered from the Accounting and Statistics Office, Keelung City Government. Multiple linear regression analysis with backward elimination was performed to determine the model that was most effective in predicting dependent variables. During the 5-year study period, the overall suicide mortality rate was negatively associated with ambient temperature. Male suicide mortality was positively correlated with unemployment, and negatively correlated with ambient temperature, barometric pressure, rainy days, family income and number of holidays. Female suicide mortality and violent suicide mortality were not significantly correlated with any meteorological or socio-economic factors. Non-violent suicide mortality was positively correlated with unemployment, and negatively correlated with ambient temperature, barometric pressure and family income. Suicide is a complex psychopathological phenomenon. Further studies with individual data are warranted to confirm how meteorological and socio-economic conditions influence ones' suicidal behaviour.

Microblower assisted barometric valve

DOEpatents

Rossabi, Joseph; Hyde, Warren K.; Riha, Brian D.; Jackson, Dennis G.; Sappington, Frank

2005-12-06

A gas exchange apparatus is provided which provides for both passive fluid flow and blower associated fluid flow through a barometric valve. A battery powered blower is provided which allows for operation of the barometric valve during times when the barometric valve would otherwise be closed, and provides for enhanced volume of gas exchange.

Theoretical and experimental analysis of laser altimeters for barometric measurements over the ocean

NASA Technical Reports Server (NTRS)

Tsai, B. M.; Gardner, C. S.

1984-01-01

The statistical characteristics and the waveforms of ocean-reflected laser pulses are studied. The received signal is found to be corrupted by shot noise and time-resolved speckle. The statistics of time-resolved speckle and its effects on the timing accuracy of the receiver are studied in the general context of laser altimetry. For estimating the differential propagation time, various receiver timing algorithms are proposed and their performances evaluated. The results indicate that, with the parameters of a realistic altimeter, a pressure measurement accuracy of a few millibars is feasible. The data obtained from the first airborne two-color laser altimeter experiment are processed and analyzed. The results are used to verify the pressure measurement concept.

40 CFR 86.143-96 - Calculations; evaporative emissions.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., provided the measured volume is determined and used for all vehicles tested by that manufacturer. (E) r=FID response factor to methanol. (F) PB=Barometric pressure, in Hg (Kpa). (G) T=Enclosure temperature, °R(°K... sampling, in. Hg. (I) i = Initial sample. (J) f = Final sample. (K) 1 = First impinger. (L) 2 = Second...

40 CFR 86.143-96 - Calculations; evaporative emissions.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., provided the measured volume is determined and used for all vehicles tested by that manufacturer. (E) r=FID response factor to methanol. (F) PB=Barometric pressure, in Hg (Kpa). (G) T=Enclosure temperature, °R(°K... sampling, in. Hg. (I) i = Initial sample. (J) f = Final sample. (K) 1 = First impinger. (L) 2 = Second...

40 CFR 86.143-96 - Calculations; evaporative emissions.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., provided the measured volume is determined and used for all vehicles tested by that manufacturer. (E) r=FID response factor to methanol. (F) PB=Barometric pressure, in Hg (Kpa). (G) T=Enclosure temperature, °R(°K... sampling, in. Hg. (I) i = Initial sample. (J) f = Final sample. (K) 1 = First impinger. (L) 2 = Second...

Daily weather variables and affective disorder admissions to psychiatric hospitals

NASA Astrophysics Data System (ADS)

McWilliams, Stephen; Kinsella, Anthony; O'Callaghan, Eadbhard

2014-12-01

Numerous studies have reported that admission rates in patients with affective disorders are subject to seasonal variation. Notwithstanding, there has been limited evaluation of the degree to which changeable daily meteorological patterns influence affective disorder admission rates. A handful of small studies have alluded to a potential link between psychiatric admission rates and meteorological variables such as environmental temperature (heat waves in particular), wind direction and sunshine. We used the Kruskal-Wallis test, ARIMA and time-series regression analyses to examine whether daily meteorological variables—namely wind speed and direction, barometric pressure, rainfall, hours of sunshine, sunlight radiation and temperature—influence admission rates for mania and depression across 12 regions in Ireland over a 31-year period. Although we found some very weak but interesting trends for barometric pressure in relation to mania admissions, daily meteorological patterns did not appear to affect hospital admissions overall for mania or depression. Our results do not support the small number of papers to date that suggest a link between daily meteorological variables and affective disorder admissions. Further study is needed.

Monitoring the Storm Tide of Hurricane Wilma in Southwestern Florida, October 2005

USGS Publications Warehouse

Soderqvist, Lars E.; Byrne, Michael J.

2007-01-01

Temporary monitoring stations employing non-vented pressure transducers were used to augment an existing U.S. Geological Survey coastal monitoring network to document the inland water levels related to the storm tide of Hurricane Wilma on the southwestern coast of Florida. On October 22, 2005, an experimental network consisting of 30 temporary stations was deployed over 90 miles of coastline to record the magnitude, extent, and timing of hurricane storm tide and coastal flooding. Sensors were programmed to record time, temperature, and barometric or water pressure. Water pressure was adjusted for changes in barometric pressure and salinity, and then converted to feet of water above the sensor. Elevation surveys using optical levels were conducted to reference storm tide water-level data and high-water marks to the North American Vertical Datum of 1988 (NAVD 88). Storm tide water levels more than 5 feet above NAVD 88 were recorded by sensors at several locations along the southwestern Florida coast. Temporary storm tide monitoring stations used for this effort have demonstrated their value in: (1) furthering the understanding of storm tide by allowing the U.S. Geological Survey to extend the scope of data collection beyond that of existing networks, and (2) serving as backup data collection at existing monitoring stations by utilizing nearby structures that are more likely to survive a major hurricane.

Integration of Infrasound, Atmospheric Pressure, and Seismic Observations with the NSF EarthScope USArray Transportable Array

NASA Astrophysics Data System (ADS)

Vernon, F.; Tytell, J.; Hedlin, M. A. H.; Walker, K.; Busby, R.; Woodward, R.

2012-04-01

Earthscope's USArray Transportable Array (TA) network serves as a real-time monitoring and recording platform for both seismic and weather phenomena. To date, most of the approximately 500 TA stations have been retrofitted with VTI SCP1000 MEMS barometric pressure gauges capable of recording data at 1 sample per second (sps). Additionally, over 300 of the TA stations have also been retrofitted with Setra 278 barometric gauges and NCPA infrasound sensors capable of recording data at 1 and 40 sps. While individual seismic events have been successfully researched via the TA network, observations of powerful weather events by the TA network have yet to be embraced by the scientific community. This presentation will focus on case studies involving severe weather passage across portions of the TA network throughout 2011 in order to highlight its viability as a platform for real-time weather monitoring and research. It will also highlight the coupling of atmospheric signals into the seismic observations. Examples of gust front passages and pressure couplets from severe thunderstorms will be presented, as will observations of multiple tornados occurred in the Spring of 2011. These data will demonstrate the overall viability of the TA network for monitoring severe weather events in real-time.

40 CFR 86.344-79 - Humidity calculations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... = Web-bulb temperature (°K) B = − 12.150799 F 0 = − 8.49922(10)3 F 1 = − 7.4231865(10)3 F 2 = 96.1635147...). ER06OC93.088 Figure D79-5—Saturation Vapor Pressure Over Water (pascals) Temperature °C 0.0 0.1 0.2 0.3 0.4... = barometric pressure (Pa) H = specific humidity, (gm H2O/gm of dry air) K = 0.6220 gm H2O/gm dry air M air...

40 CFR 86.344-79 - Humidity calculations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... = Web-bulb temperature (°K) B = − 12.150799 F 0 = − 8.49922(10)3 F 1 = − 7.4231865(10)3 F 2 = 96.1635147...). ER06OC93.088 Figure D79-5—Saturation Vapor Pressure Over Water (pascals) Temperature °C 0.0 0.1 0.2 0.3 0.4... = barometric pressure (Pa) H = specific humidity, (gm H2O/gm of dry air) K = 0.6220 gm H2O/gm dry air M air...

Evaluation of the Environmental Bias on Accelerometer-Measured Total Daily Activity Counts and Owner Survey Responses in Dogs with Osteoarthritis.

PubMed

Katz, Erin M; Scott, Ruth M; Thomson, Christopher B; Mesa, Eileen; Evans, Richard; Conzemius, Michael G

2017-11-01

Objective  To determine if environmental variables affect the average daily activity counts (AC) of dogs with osteoarthritis (OA) and/or owners' perception of their dog's clinical signs or quality of life. Methods  The AC and Canine Brief Pain Inventory (CBPI) owner questionnaires of 62 dogs with OA were compared with daily environmental variables including the following: average temperature (°C), high temperature (°C), low temperature (°C), relative humidity (%), total precipitation (mm), average barometric pressure (hPa) and total daylight hours. Results  Daily AC significantly correlated with average temperature and total daylight hours, but average temperature and total daylight hours accounted for less than 1% of variation in AC. No other significant relationships were found between daily AC and daily high temperature, low temperature, relative humidity, total precipitation or average barometric pressure. No statistical relationship was found between daily AC and the CBPI, nor between environmental variables and the CBPI. Canine Brief Pain Inventory scores for pain severity and pain interference decreased significantly over the test period. Clinical Significance  The relationship between daily AC and average temperature and total daylight hours was significant, but unlikely to be clinically significant. Thus, environmental variables do not appear to have a clinically relevant bias on AC or owner CBPI questionnaires. The decrease over time in CBPI pain severity and pain interference values suggests owners completing the CBPI in this study were influenced by a caregiver placebo effect. Schattauer GmbH Stuttgart.

40 CFR 1033.655 - Special provisions for certain Tier 0/Tier 1 locomotives.

Code of Federal Regulations, 2012 CFR

2012-07-01

... locomotives covered by this section. (c) You may ask us to allow these locomotives to exceed otherwise applicable line-haul cycle NOX standard for high ambient temperatures and/or altitude because of limitations... locomotives, you may ask for relief for ambient temperatures above 23 °C and/or barometric pressure below 97.5...

40 CFR 1033.655 - Special provisions for certain Tier 0/Tier 1 locomotives.

Code of Federal Regulations, 2013 CFR

2013-07-01

... locomotives covered by this section. (c) You may ask us to allow these locomotives to exceed otherwise applicable line-haul cycle NOX standard for high ambient temperatures and/or altitude because of limitations... locomotives, you may ask for relief for ambient temperatures above 23 °C and/or barometric pressure below 97.5...

40 CFR 1033.655 - Special provisions for certain Tier 0/Tier 1 locomotives.

Code of Federal Regulations, 2014 CFR

2014-07-01

... locomotives covered by this section. (c) You may ask us to allow these locomotives to exceed otherwise applicable line-haul cycle NOX standard for high ambient temperatures and/or altitude because of limitations... locomotives, you may ask for relief for ambient temperatures above 23 °C and/or barometric pressure below 97.5...

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2014 CFR

2014-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2010 CFR

2010-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2012 CFR

2012-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2011 CFR

2011-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2013 CFR

2013-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

DITT: a computer program for Data Interpretation for Torsional Tests

USGS Publications Warehouse

Chen, Albert T.F.

1979-01-01

Measurements of the helium concentration of soil samples collected and stored in Vacutainer-brand evacuated glass tubes show that Vacutainers are reliable containers for soil collection. Within the limits of reproducibility, helium content of soils appears to be independent of variations in soil temperature, barometric pressure, and quantity of soil moisture present in the sample.

The Relationship between Weather and Lunar Changes on Student Achievement and Measures School Districts Utilize to Combat Potential Impact

ERIC Educational Resources Information Center

Stuart, Kendra

2013-01-01

Classroom disruptions present an obstacle to raising student achievement for teachers and school administrators. This study was designed to investigate potential relationships between weather, specifically barometric pressure, or the lunar cycle, and whether either had a direct correlation with student discipline referrals. The intent was to…

40 CFR 86.117-96 - Evaporative emission enclosure calibrations.

Code of Federal Regulations, 2014 CFR

2014-07-01

...), as measured in paragraph (b)(1) of this section. (v) r=FID response factor to methanol. (vi) PB = Barometric pressure, in. Hg. (kPa). (vii) T=Enclosure ambient temperature, R(K). (viii) i=Indicates initial reading. (ix) f=Indicates final reading. (x)(A) k=3.05. (B) For SI units, k=17.60. (xi) MHC, out = mass of...

40 CFR 86.1243-96 - Calculations; evaporative emissions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the measured volume is determined and used for all vehicles tested by that manufacturer. (E) r=FID response factor to methanol. (F) PB=Barometric pressure, in Hg (Kpa). (G) T=Enclosure temperature, °R(°K... sampling, in. Hg. (I) i=Initial sample. (J) f=Final sample. (K) 1=First impinger. (L) 2=Second impinger. (M...

40 CFR 86.1243-96 - Calculations; evaporative emissions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the measured volume is determined and used for all vehicles tested by that manufacturer. (E) r=FID response factor to methanol. (F) PB=Barometric pressure, in Hg (Kpa). (G) T=Enclosure temperature, °R(°K... sampling, in. Hg. (I) i=Initial sample. (J) f=Final sample. (K) 1=First impinger. (L) 2=Second impinger. (M...

40 CFR 86.1243-96 - Calculations; evaporative emissions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the measured volume is determined and used for all vehicles tested by that manufacturer. (E) r=FID response factor to methanol. (F) PB=Barometric pressure, in Hg (Kpa). (G) T=Enclosure temperature, °R(°K... sampling, in. Hg. (I) i=Initial sample. (J) f=Final sample. (K) 1=First impinger. (L) 2=Second impinger. (M...

40 CFR 86.117-96 - Evaporative emission enclosure calibrations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... this section. (v) r=FID response factor to methanol. (vi) PB=Barometric pressure, in. Hg. (kPa). (vii) T=Enclosure ambient temperature, R(K). (viii) i=Indicates initial reading. (ix) f=Indicates final reading. (x)(A) k=3.05. (B) For SI units, k=17.60. (xi) MHC, out=mass of hydrocarbon exiting the enclosure...

40 CFR 86.117-96 - Evaporative emission enclosure calibrations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... this section. (v) r=FID response factor to methanol. (vi) PB=Barometric pressure, in. Hg. (kPa). (vii) T=Enclosure ambient temperature, R(K). (viii) i=Indicates initial reading. (ix) f=Indicates final reading. (x)(A) k=3.05. (B) For SI units, k=17.60. (xi) MHC, out=mass of hydrocarbon exiting the enclosure...

Acquisition of Crosswell Seismic Monitoring Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daley, T.M.; Niu, F.; Silver, P.G.

2008-02-15

Crosswell seismic acquisition provides an ideal geometry for monitoring travel time changes in the subsurface. Analysis of delay time in terms of a characteristic frequency allows us to estimate optimal acquisition parameters (frequency and distance). We have deployed standard data acquisition equipment for continuous monitoring of crosswell travel time in two separate field experiments, with well spacing of 3 and 30 m. The acquisition hardware used for the field experiments is described, along with environmental effects (such as temperature) that influence the measurements. Two field experiments are described that correlate changes in travel time (and therefore velocity) with changes inmore » barometric pressure. The results from the two field sites show a pressure sensitivity for velocity of 10{sup -6}/Pa to 10{sup -8}/Pa.« less

Zero-fringe demodulation method based on location-dependent birefringence dispersion in polarized low-coherence interferometry.

PubMed

Wang, Shuang; Liu, Tiegen; Jiang, Junfeng; Liu, Kun; Yin, Jinde; Qin, Zunqi; Zou, Shengliang

2014-04-01

We present a high precision and fast speed demodulation method for a polarized low-coherence interferometer with location-dependent birefringence dispersion. Based on the characteristics of location-dependent birefringence dispersion and five-step phase-shifting technology, the method accurately retrieves the peak position of zero-fringe at the central wavelength, which avoids the fringe order ambiguity. The method processes data only in the spatial domain and reduces the computational load greatly. We successfully demonstrated the effectiveness of the proposed method in an optical fiber Fabry-Perot barometric pressure sensing experiment system. Measurement precision of 0.091 kPa was realized in the pressure range of 160 kPa, and computation time was improved by 10 times compared to the traditional phase-based method that requires Fourier transform operation.

A sensor fusion method for tracking vertical velocity and height based on inertial and barometric altimeter measurements.

PubMed

Sabatini, Angelo Maria; Genovese, Vincenzo

2014-07-24

A sensor fusion method was developed for vertical channel stabilization by fusing inertial measurements from an Inertial Measurement Unit (IMU) and pressure altitude measurements from a barometric altimeter integrated in the same device (baro-IMU). An Extended Kalman Filter (EKF) estimated the quaternion from the sensor frame to the navigation frame; the sensed specific force was rotated into the navigation frame and compensated for gravity, yielding the vertical linear acceleration; finally, a complementary filter driven by the vertical linear acceleration and the measured pressure altitude produced estimates of height and vertical velocity. A method was also developed to condition the measured pressure altitude using a whitening filter, which helped to remove the short-term correlation due to environment-dependent pressure changes from raw pressure altitude. The sensor fusion method was implemented to work on-line using data from a wireless baro-IMU and tested for the capability of tracking low-frequency small-amplitude vertical human-like motions that can be critical for stand-alone inertial sensor measurements. Validation tests were performed in different experimental conditions, namely no motion, free-fall motion, forced circular motion and squatting. Accurate on-line tracking of height and vertical velocity was achieved, giving confidence to the use of the sensor fusion method for tracking typical vertical human motions: velocity Root Mean Square Error (RMSE) was in the range 0.04-0.24 m/s; height RMSE was in the range 5-68 cm, with statistically significant performance gains when the whitening filter was used by the sensor fusion method to track relatively high-frequency vertical motions.

A framework for relating the structures and recovery statistics in pressure time-series surveys for dust devils

NASA Astrophysics Data System (ADS)

Jackson, Brian; Lorenz, Ralph; Davis, Karan

2018-01-01

Dust devils are likely the dominant source of dust for the martian atmosphere, but the amount and frequency of dust-lifting depend on the statistical distribution of dust devil parameters. Dust devils exhibit pressure perturbations and, if they pass near a barometric sensor, they may register as a discernible dip in a pressure time-series. Leveraging this fact, several surveys using barometric sensors on landed spacecraft have revealed dust devil structures and occurrence rates. However powerful they are, though, such surveys suffer from non-trivial biases that skew the inferred dust devil properties. For example, such surveys are most sensitive to dust devils with the widest and deepest pressure profiles, but the recovered profiles will be distorted, broader and shallow than the actual profiles. In addition, such surveys often do not provide wind speed measurements alongside the pressure time series, and so the durations of the dust devil signals in the time series cannot be directly converted to profile widths. Fortunately, simple statistical and geometric considerations can de-bias these surveys, allowing conversion of the duration of dust devil signals into physical widths, given only a distribution of likely translation velocities, and the recovery of the underlying distributions of physical parameters. In this study, we develop a scheme for de-biasing such surveys. Applying our model to an in-situ survey using data from the Phoenix lander suggests a larger dust flux and a dust devil occurrence rate about ten times larger than previously inferred. Comparing our results to dust devil track surveys suggests only about one in five low-pressure cells lifts sufficient dust to leave a visible track.

The use of Vacutainer tubes for collection of soil samples for helium analysis

USGS Publications Warehouse

Hinkle, Margaret E.; Kilburn, James E.

1979-01-01

Measurements of the helium concentration of soil samples collected and stored in Vacutainer-brand evacuated glass tubes show that Vacutainers are reliable containers for soil collection. Within the limits of reproducibility, helium content of soils appears to be independent of variations in soil temperature, barometric pressure, and quantity of soil moisture present in the sample.

40 CFR 86.1217-96 - Evaporative emission enclosure calibrations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... volume ft3 (m3), as measured in paragraph (b)(1) of this section. (v) r=FID response factor to methanol. (vi) PB=Barometric pressure, in. Hg. (kPa). (vii) T=Enclosure ambient temperature, R(K). (viii) i=Indicates initial reading. (ix) f=Indicates final reading. (x)(A) k=3.05. (B) For SI units, k=17.60. (xi...

40 CFR 86.1217-96 - Evaporative emission enclosure calibrations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... volume ft3 (m3), as measured in paragraph (b)(1) of this section. (v) r=FID response factor to methanol. (vi) PB=Barometric pressure, in. Hg. (kPa). (vii) T=Enclosure ambient temperature, R(K). (viii) i=Indicates initial reading. (ix) f=Indicates final reading. (x)(A) k=3.05. (B) For SI units, k=17.60. (xi...

A Wave Glider for Studies of Biofouling and Ocean Productivity

DTIC Science & Technology

2017-11-07

sensors for conductivity, water and air temperature , dissolved oxygen , chlorophyll-a fluorescence, wind speed and direction, barometric pressure, and...endurance, reduce fuel consumption , and reduce carbon emissions. During deployments, vessels encounter a range of planktonic assemblages and ocean...with an acoustic Doppler current profiler, an optical camera system, and standard sensors for conductivity, water and air temperature , dissolved

Activity classification based on inertial and barometric pressure sensors at different anatomical locations.

PubMed

Moncada-Torres, A; Leuenberger, K; Gonzenbach, R; Luft, A; Gassert, R

2014-07-01

Miniature, wearable sensor modules are a promising technology to monitor activities of daily living (ADL) over extended periods of time. To assure both user compliance and meaningful results, the selection and placement site of sensors requires careful consideration. We investigated these aspects for the classification of 16 ADL in 6 healthy subjects under laboratory conditions using ReSense, our custom-made inertial measurement unit enhanced with a barometric pressure sensor used to capture activity-related altitude changes. Subjects wore a module on each wrist and ankle, and one on the trunk. Activities comprised whole body movements as well as gross and dextrous upper-limb activities. Wrist-module data outperformed the other locations for the three activity groups. Specifically, overall classification accuracy rates of almost 93% and more than 95% were achieved for the repeated holdout and user-specific validation methods, respectively, for all 16 activities. Including the altitude profile resulted in a considerable improvement of up to 20% in the classification accuracy for stair ascent and descent. The gyroscopes provided no useful information for activity classification under this scheme. The proposed sensor setting could allow for robust long-term activity monitoring with high compliance in different patient populations.

Low-power sensor module for long-term activity monitoring.

PubMed

Leuenberger, Kaspar; Gassert, Roger

2011-01-01

Wearable sensor modules are a promising approach to collecting data on functional motor activities, both for repeated and long-term assessments, as well as to investigate the transfer of therapy to activities of daily living at home, but have so far either had limited sensing capabilities, or were not laid out for long-term monitoring. This paper presents ReSense, a miniature sensor unit optimized for long-term monitoring of functional activity. Inertial MEMS sensors capture accelerations along six degrees of freedom and a barometric pressure sensor serves as a precise altimeter. Data is written to an integrated memory card. The realized module measures Ø25 × 10 mm, weighs 10 g and can record continuously for 27 h at 25 Hz and over 22 h at 100 Hz. The integrated power-management system detects inactivity and extends the operating time by about a factor of two, as shown by initial 24 h recordings on five energetic healthy adults. The integrated barometric pressure sensor allowed to identify activities incorporating a change in altitude, such as going up/down stairs or riding an elevator. By taking into account data from the inertial sensors during the altitude changes, it becomes possible to distinguish between these two activities.

Domestic Violence in a subtropical environment: Police calls and weather in Brisbane

NASA Astrophysics Data System (ADS)

Auliciems, A.; Dibartolo, L.

1995-03-01

Possible relationships between weather and telephone calls to police' complaining of domestic violence, were investigated for Brisbane during 1992. Having accounted for the effect of the day of the week, significant associations were observed between calls and maximum air temperature, during all seasons. Prediction equations have been established for different days of the week. At the weekly level, the temperature association was enhanced by barometric pressure, yielding a regression which explained nearly 50% of the overall variability. It is suggested that the inputs into these regressions can be adequately forecasted, and that appropriate procedures may be developed for their practical application.

Relationship between temperature change and the requirement for a permanent pacemaker implantation in bradyarrhythmias.

PubMed

Liu, I-Fan; Chang, Shih-Lin; Lo, Li-Wei; Hu, Yu-Feng; Tuan, Ta-Chuan; Kong, Chi-Woon; Wu, Tsu-Juey; Chiang, Chern-En; Chen, Shih-Ann; Lin, Yenn-Jiang

2011-09-01

Some cardiovascular diseases are associated with seasonal or meteorological factors. We tried to identify the relationship between meteorological parameters and the requirement for a permanent pacemaker (PPM) implantation for advanced sinus node dysfunction (SND) and atrioventricular block (AVB). This study enrolled 656 patients (67% male, age = 76 ± 11 years) who underwent a PPM implantation due to SND or AVB from January 2004 to December 2008. Using daily temperature, barometric pressure, humidity, and daylight hour records from Taipei, we evaluated the effect of these meteorological parameters within different time periods on the occurrence of SND and AVB. There were 355 patients in the SND group and 301 in the AVB group. In the AVB group, more patients presented in the spring than in other seasons (P = 0.003). In the SND group, there was no relationship with the seasons (P = 0.137). The proportion of patients with AVB did not depend on the average temperature, barometric pressure, humidity, or daylight hours within 3, 7, and 14 days prior to admission (P = NS). A temperature change of greater than 11°C within 30 days prior to admission was associated with a significantly higher proportion of patients with advanced AVB compared to those with advanced SND (P = 0.009). Extreme change in temperature was the most independent predictor of the development of advanced AVB. The peak occurrence of advanced AVB was in the spring. The occurrence of advanced AVB was associated with extreme temperature changes within 30 days, especially in the spring.

Displacements of the earth's surface due to atmospheric loading - Effects of gravity and baseline measurements

NASA Technical Reports Server (NTRS)

Van Dam, T. M.; Wahr, J. M.

1987-01-01

Atmospheric mass loads and deforms the earth's crust. By performing a convolution sum between daily, global barometric pressure data and mass loading Green's functions, the time dependent effects of atmospheric loading, including those associated with short-term synoptic storms, on surface point positioning measurements and surface gravity observations are estimated. The response for both an oceanless earth and an earth with an inverted barometer ocean is calculated. Load responses for near-coastal stations are significantly affected by the inclusion of an inverted barometer ocean. Peak-to-peak vertical displacements are frequently 15-20 mm with accompanying gravity perturbations of 3-6 micro Gal. Baseline changes can be as large as 20 mm or more. The perturbations are largest at higher latitudes and during winter months. These amplitudes are consistent with the results of Rabbel and Zschau (1985), who modeled synoptic pressure disturbances as Gaussian functions of radius around a central point. Deformation can be adequately computed using real pressure data from points within about 1000 km of the station. Knowledge of local pressure, alone, is not sufficient. Rabbel and Zschau's hypothesized corrections for these displacements, which use local pressure and the regionally averaged pressure, prove accurate at points well inland but are, in general, inadequate within a few hundred kilometers of the coast.

Hurricane Rita surge data, southwestern Louisiana and southeastern Texas, September to November 2005

USGS Publications Warehouse

McGee, Benton D.; Goree, Burl B.; Tollett, Roland W.; Woodward, Brenda K.; Kress, Wade H.

2006-01-01

Pressure transducers and high-water marks were used to document the inland water levels related to storm surge generated by Hurricane Rita in southwestern Louisiana and southeastern Texas. On September 22-23, 2005, an experimental monitoring network consisting of 47 pressure transducers (sensors) was deployed at 33 sites over an area of about 4,000 square miles to record the timing, extent, and magnitude of inland hurricane storm surge and coastal flooding. Sensors were programmed to record date and time, temperature, and barometric or water pressure. Water pressure was corrected for changes in barometric pressure and salinity. Elevation surveys using global-positioning systems and differential levels were used to relate all storm-surge water-level data, reference marks, benchmarks, sensor measuring points, and high-water marks to the North American Vertical Datum of 1988 (NAVD 88). The resulting data indicated that storm-surge water levels over 14 feet above NAVD 88 occurred at three locations and rates of water-level rise greater than 5 feet per hour occurred at three locations near the Louisiana coast. Quality-assurance measures were used to assess the variability and accuracy of the water-level data recorded by the sensors. Water-level data from sensors were similar to data from co-located sensors, permanent U.S. Geological Survey streamgages, and water-surface elevations performed by field staff. Water-level data from sensors at selected locations were compared to corresponding high-water mark elevations. In general, the water-level data from sensors were similar to elevations of high quality high-water marks, while reporting consistently higher than elevations of lesser quality high-water marks.

Remote Sensing Global Surface Air Pressure Using Differential Absorption BArometric Radar (DiBAR)

NASA Technical Reports Server (NTRS)

Lin, Bing; Harrah, Steven; Lawrence, Wes; Hu, Yongxiang; Min, Qilong

2016-01-01

Tropical storms and severe weathers are listed as one of core events that need improved observations and predictions in World Meteorological Organization and NASA Decadal Survey (DS) documents and have major impacts on public safety and national security. This effort tries to observe surface air pressure, especially over open seas, from space using a Differential-absorption BArometric Radar (DiBAR) operating at the 50-55 gigahertz O2 absorption band. Air pressure is among the most important variables that affect atmospheric dynamics, and currently can only be measured by limited in-situ observations over oceans. Analyses show that with the proposed space radar the errors in instantaneous (averaged) pressure estimates can be as low as approximately 4 millibars (approximately 1 millibar under all weather conditions). With these sea level pressure measurements, the forecasts of severe weathers such as hurricanes will be significantly improved. Since the development of the DiBAR concept about a decade ago, NASA Langley DiBAR research team has made substantial progress in advancing the concept. The feasibility assessment clearly shows the potential of sea surface barometry using existing radar technologies. The team has developed a DiBAR system design, fabricated a Prototype-DiBAR (P-DiBAR) for proof-of-concept, conducted lab, ground and airborne P-DiBAR tests. The flight test results are consistent with the instrumentation goals. Observational system simulation experiments for space DiBAR performance based on the existing DiBAR technology and capability show substantial improvements in tropical storm predictions, not only for the hurricane track and position but also for the hurricane intensity. DiBAR measurements will lead us to an unprecedented level of the prediction and knowledge on global extreme weather and climate conditions.

A Sensor Fusion Method for Tracking Vertical Velocity and Height Based on Inertial and Barometric Altimeter Measurements

PubMed Central

Sabatini, Angelo Maria; Genovese, Vincenzo

2014-01-01

A sensor fusion method was developed for vertical channel stabilization by fusing inertial measurements from an Inertial Measurement Unit (IMU) and pressure altitude measurements from a barometric altimeter integrated in the same device (baro-IMU). An Extended Kalman Filter (EKF) estimated the quaternion from the sensor frame to the navigation frame; the sensed specific force was rotated into the navigation frame and compensated for gravity, yielding the vertical linear acceleration; finally, a complementary filter driven by the vertical linear acceleration and the measured pressure altitude produced estimates of height and vertical velocity. A method was also developed to condition the measured pressure altitude using a whitening filter, which helped to remove the short-term correlation due to environment-dependent pressure changes from raw pressure altitude. The sensor fusion method was implemented to work on-line using data from a wireless baro-IMU and tested for the capability of tracking low-frequency small-amplitude vertical human-like motions that can be critical for stand-alone inertial sensor measurements. Validation tests were performed in different experimental conditions, namely no motion, free-fall motion, forced circular motion and squatting. Accurate on-line tracking of height and vertical velocity was achieved, giving confidence to the use of the sensor fusion method for tracking typical vertical human motions: velocity Root Mean Square Error (RMSE) was in the range 0.04–0.24 m/s; height RMSE was in the range 5–68 cm, with statistically significant performance gains when the whitening filter was used by the sensor fusion method to track relatively high-frequency vertical motions. PMID:25061835

The effect of regional sea level atmospheric pressure on sea level variations at globally distributed tide gauge stations with long records

NASA Astrophysics Data System (ADS)

Iz, H. Bâki

2018-05-01

This study provides additional information about the impact of atmospheric pressure on sea level variations. The observed regularity in sea level atmospheric pressure depends mainly on the latitude and verified to be dominantly random closer to the equator. It was demonstrated that almost all the annual and semiannual sea level variations at 27 globally distributed tide gauge stations can be attributed to the regional/local atmospheric forcing as an inverted barometric effect. Statistically significant non-linearities were detected in the regional atmospheric pressure series, which in turn impacted other sea level variations as compounders in tandem with the lunar nodal forcing, generating lunar sub-harmonics with multidecadal periods. It was shown that random component of regional atmospheric pressure tends to cluster at monthly intervals. The clusters are likely to be caused by the intraannual seasonal atmospheric temperature changes,which may also act as random beats in generating sub-harmonics observed in sea level changes as another mechanism. This study also affirmed that there are no statistically significant secular trends in the progression of regional atmospheric pressures, hence there was no contribution to the sea level trends during the 20th century by the atmospheric pressure.Meanwhile, the estimated nonuniform scale factors of the inverted barometer effects suggest that the sea level atmospheric pressure will bias the sea level trends inferred from satellite altimetry measurements if their impact is accounted for as corrections without proper scaling.

Effect of aircraft-cabin altitude on passenger discomfort.

PubMed

Muhm, J Michael; Rock, Paul B; McMullin, Dianne L; Jones, Stephen P; Lu, I L; Eilers, Kyle D; Space, David R; McMullen, Aleksandra

2007-07-05

Acute mountain sickness occurs in some unacclimatized persons who travel to terrestrial altitudes at which barometric pressures are the same as those in commercial aircraft during flight. Whether the effects are similar in air travelers is unknown. We conducted a prospective, single-blind, controlled hypobaric-chamber study of adult volunteers to determine the effect of barometric pressures equivalent to terrestrial altitudes of 650, 4000, 6000, 7000, and 8000 ft (198, 1219, 1829, 2134, and 2438 m, respectively) above sea level on arterial oxygen saturation and the occurrence of acute mountain sickness and discomfort as measured by responses to the Environmental Symptoms Questionnaire IV during a 20-hour simulated flight. Among the 502 study participants, the mean oxygen saturation decreased with increasing altitude, with a maximum decrease of 4.4 percentage points (95% confidence interval, 3.9 to 4.9) at 8000 ft. Overall, acute mountain sickness occurred in 7.4% of the participants, but its frequency did not vary significantly among the altitudes studied. The frequency of reported discomfort increased with increasing altitude and decreasing oxygen saturation and was greater at 7000 to 8000 ft than at all the lower altitudes combined. Differences became apparent after 3 to 9 hours of exposure. Persons older than 60 years of age were less likely than younger persons and men were less likely than women to report discomfort. Four serious adverse events, 1 of which may have been related to the study exposures, and 15 adverse events, 9 of which were related to study exposures, were reported. Ascent from ground level to the conditions of 7000 to 8000 ft lowered oxygen saturation by approximately 4 percentage points. This level of hypoxemia was insufficient to affect the occurrence of acute mountain sickness but did contribute to the increased frequency of reports of discomfort in unacclimatized participants after 3 to 9 hours. (ClinicalTrials.gov number, NCT00326703 [ClinicalTrials.gov].). Copyright 2007 Massachusetts Medical Society.

System for the removal of contaminant soil-gas vapors

DOEpatents

Weidner, Jerry R.; Downs, Wayne C.; Kaser, Timothy G.; Hall, H. James

1997-01-01

A system extracts contaminated vapors from soil or other subsurface regions by using changes in barometric pressure to operate sensitive check valves that control air entry and removal from wells in the ground. The system creates an efficient subterranean flow of air through a contaminated soil plume and causes final extraction of the contaminants from the soil to ambient air above ground without any external energy sources.

System for the removal of contaminant soil-gas vapors

DOEpatents

Weidner, J.R.; Downs, W.C.; Kaser, T.G.; Hall, H.J.

1997-12-16

A system extracts contaminated vapors from soil or other subsurface regions by using changes in barometric pressure to operate sensitive check valves that control air entry and removal from wells in the ground. The system creates an efficient subterranean flow of air through a contaminated soil plume and causes final extraction of the contaminants from the soil to ambient air above ground without any external energy sources. 4 figs.

Exploiting a GSM Network for Precise Payload Delivery

DTIC Science & Technology

2009-05-07

N is shown in Fig.6. As shown in this figure the Snowflake payload now includes a standard Blackberry 8310 cell phone , which communicates with the...weather station, measuring winds and barometric pressure, serial to Bluetooth interface, and Blackberry 8310 cell phone . The portable Kestrel 4000...interfacing the serial stream with a standard Blackberry 8310 cell phone carrying a AT&T SIM card. 6 American Institute of Aeronautics and

Effects of oxygen-augmented atmosphere on the immune response.

NASA Technical Reports Server (NTRS)

Guttman, H. N.

1973-01-01

Antibovine serum albumin antibody and nonspecific protein production was evaluated in female rabbits (11-14.5 kg) housed in special cages ventilated with 20% or 40% oxygen at normal barometric pressure. Animals exposed to 40% oxygen do not show normal steady increase of serum antibody. Instead, their titers show a pattern of undershoot, overshoot, undershoot, and finally equilibration at a subnormal level; they have a depressed popliteal node polysome level and have an abnormally low proportion of membrane-bound polysomes. They also show reduced capability of popliteal nodes to synthesize protein (as expected from the reduced number of polysomes). However, the ratio of newly-synthesized specific antibody: nonspecific protein remains normal.

Barometric pressure change and heart rate response during sleeping at 3000 m altitude

NASA Astrophysics Data System (ADS)

Horiuchi, Masahiro; Endo, Junko; Handa, Yoko; Nose, Hiroshi

2018-05-01

We investigated effects of change in barometric pressure ( P B) with climate change on heart rate (HR) during sleep at 3000 m altitude. Nineteen healthy adults (15 males and four females; mean age 32 years) participated in this study. We measured P B (barometry) and HR (electrocardiography) every minute during their overnight stay in a mountain lodge at 3000 m. We also measured resting arterial oxygen saturation (SpO2) and evaluated symptoms of acute mountain sickness (AMS) by using the Lake Louise Questionnaire at 2305 and 3000 m, respectively. P B gradually decreased during the night at the speed of approximately - 0.5 hPa/h. We found that HR during sleep decreased linearly as P B decreased in all subjects, with significance ( r = 0.492-0.893; all, P < 0.001). Moreover, cross correlation analysis revealed that HR started to decrease after 15 min following the decrease in P B, on average. SpO2 was 93.8 ± 1.7% at 2305 m before climbing, then decreased significantly to 90.2 ± 2.2% at the lodge before going to bed, and further decreased to 87.5 ± 2.7% after waking (all, P < 0.05). Four of the 19 subjects showed a symptom of AMS after waking (21%). Further, the decrease in HR in response to a given decrease in P B (ΔHR/ΔPB) was negatively related with a decrease in SpO2 from before going to bed to after waking at 3000 m ( r = - 0.579, P = 0.009) and with total AMS scores after waking ( r = 0.489, P = 0.033).

Barometric pressure change and heart rate response during sleeping at 3000 m altitude

NASA Astrophysics Data System (ADS)

Horiuchi, Masahiro; Endo, Junko; Handa, Yoko; Nose, Hiroshi

2017-12-01

We investigated effects of change in barometric pressure (P B) with climate change on heart rate (HR) during sleep at 3000 m altitude. Nineteen healthy adults (15 males and four females; mean age 32 years) participated in this study. We measured P B (barometry) and HR (electrocardiography) every minute during their overnight stay in a mountain lodge at 3000 m. We also measured resting arterial oxygen saturation (SpO2) and evaluated symptoms of acute mountain sickness (AMS) by using the Lake Louise Questionnaire at 2305 and 3000 m, respectively. P B gradually decreased during the night at the speed of approximately - 0.5 hPa/h. We found that HR during sleep decreased linearly as P B decreased in all subjects, with significance (r = 0.492-0.893; all, P < 0.001). Moreover, cross correlation analysis revealed that HR started to decrease after 15 min following the decrease in P B, on average. SpO2 was 93.8 ± 1.7% at 2305 m before climbing, then decreased significantly to 90.2 ± 2.2% at the lodge before going to bed, and further decreased to 87.5 ± 2.7% after waking (all, P < 0.05). Four of the 19 subjects showed a symptom of AMS after waking (21%). Further, the decrease in HR in response to a given decrease in P B (ΔHR/ΔPB) was negatively related with a decrease in SpO2 from before going to bed to after waking at 3000 m (r = - 0.579, P = 0.009) and with total AMS scores after waking (r = 0.489, P = 0.033).

Does cerebral oxygen delivery limit incremental exercise performance?

PubMed Central

Olin, J. Tod; Dimmen, Andrew C.; Polaner, David M.; Kayser, Bengt; Roach, Robert C.

2011-01-01

Previous studies have suggested that a reduction in cerebral oxygen delivery may limit motor drive, particularly in hypoxic conditions, where oxygen transport is impaired. We hypothesized that raising end-tidal Pco2 (PetCO2) during incremental exercise would increase cerebral blood flow (CBF) and oxygen delivery, thereby improving peak power output (Wpeak). Amateur cyclists performed two ramped exercise tests (25 W/min) in a counterbalanced order to compare the normal, poikilocapnic response against a clamped condition, in which PetCO2 was held at 50 Torr throughout exercise. Tests were performed in normoxia (barometric pressure = 630 mmHg, 1,650 m) and hypoxia (barometric pressure = 425 mmHg, 4,875 m) in a hypobaric chamber. An additional trial in hypoxia investigated effects of clamping at a lower PetCO2 (40 Torr) from ∼75 to 100% Wpeak to reduce potential influences of respiratory acidosis and muscle fatigue imposed by clamping PetCO2 at 50 Torr. Metabolic gases, ventilation, middle cerebral artery CBF velocity (transcranial Doppler), forehead pulse oximetry, and cerebral (prefrontal) and muscle (vastus lateralis) hemoglobin oxygenation (near infrared spectroscopy) were monitored across trials. Clamping PetCO2 at 50 Torr in both normoxia (n = 9) and hypoxia (n = 11) elevated CBF velocity (∼40%) and improved cerebral hemoglobin oxygenation (∼15%), but decreased Wpeak (6%) and peak oxygen consumption (11%). Clamping at 40 Torr near maximal effort in hypoxia (n = 6) also improved cerebral oxygenation (∼15%), but again limited Wpeak (5%). These findings demonstrate that increasing mass cerebral oxygen delivery via CO2-mediated vasodilation does not improve incremental exercise performance, at least when accompanied by respiratory acidosis. PMID:21921244

Active Sensing Air Pressure Using Differential Absorption Barometric Radar

NASA Astrophysics Data System (ADS)

Lin, B.

2016-12-01

Tropical storms and other severe weathers cause huge life losses and property damages and have major impacts on public safety and national security. Their observations and predictions need to be significantly improved. This effort tries to develop a feasible active microwave approach that measures surface air pressure, especially over open seas, from space using a Differential-absorption BArometric Radar (DiBAR) operating at 50-55 GHz O2 absorption band in order to constrain assimilated dynamic fields of numerical weather Prediction (NWP) models close to actual conditions. Air pressure is the most important variable that drives atmospheric dynamics, and currently can only be measured by limited in-situ observations over oceans. Even over land there is no uniform coverage of surface air pressure measurements. Analyses show that with the proposed space radar the errors in instantaneous (averaged) pressure estimates can be as low as 4mb ( 1mb) under all weather conditions. NASA Langley research team has made substantial progresses in advancing the DiBAR concept. The feasibility assessment clearly shows the potential of surface barometry using existing radar technologies. The team has also developed a DiBAR system design, fabricated a Prototype-DiBAR (P-DiBAR) for proof-of-concept, conducted laboratory, ground and airborne P-DiBAR tests. The flight test results are consistent with the instrumentation goals. The precision and accuracy of radar surface pressure measurements are within the range of the theoretical analysis of the DiBAR concept. Observational system simulation experiments for space DiBAR performance based on the existing DiBAR technology and capability show substantial improvements in tropical storm predictions, not only for the hurricane track and position but also for the hurricane intensity. DiBAR measurements will provide us an unprecedented level of the prediction and knowledge on global extreme weather and climate conditions.

Assessment of pore pressures and specific storage within sedimentary strata overlying underground mines

NASA Astrophysics Data System (ADS)

Timms, W.; David, K.; Barbour, L. S.

2016-12-01

Realistic values of specific storage (Ss) for groundwater systems are important to determine the spatial extent and timing of c pore pressure changes when the groundwater system is stressed. However, numerical groundwater models of underground excavations typically assume constant literature values of Ss. One part of our research program utilised high frequency pore pressure data to evaluate variability and changes in Ss within sedimentary strata overlying a longwall coal mine. Pore pressure data from a vertical series of 6 vibrating wire piezometers (50 to 278 m depth) recording at hourly intervals were compared with barometric pressure data over a period of several years, including data before and during mining. The site was located near the centre of a longwall panel that extracted 3 m of coal at a depth of 330 m. The data was processed to calculate loading efficiency and Ss values by multi-method analyses of barometric and earth tide responses. In situ Ss results varied over one to two orders of magnitude and indicated that Ss changed before and after excavation of underlying coal seams. The vertical leakage of groundwater within the constrained zone ( 10 to 150 m depth) was found to be limited, although some degree of vertical hydraulic connectivity was observed. Depressurization was evident in the fractured zone directly overlying the coal seam, and Ss changes at 250 m depth indicated this confined aquifer may have become unconfined. Our results demonstrate that high frequency pore pressure data can provide realistic Ss values. In situ Ss values were an order of magnitude lower than Ss measured by geomechnical tests of cores, and were significantly different to textbook values set in most local groundwater models. The timing and extent of groundwater level drawdown predicted by models may therefore be underestimated. We have shown, for the first time, that variability of Ss can be significant, and that these changes can provide important insights into how shallow and deep groundwater systems respond to underground mining.

Monitoring Changes of Tropical Extreme Rainfall Events Using Differential Absorption Barometric Radar (DiBAR)

NASA Technical Reports Server (NTRS)

Lin, Bing; Harrah, Steven; Lawrence, R. Wes; Hu, Yongxiang; Min, Qilong

2015-01-01

This work studies the potential of monitoring changes in tropical extreme rainfall events such as tropical storms from space using a Differential-absorption BArometric Radar (DiBAR) operating at 50-55 gigahertz O2 absorption band to remotely measure sea surface air pressure. Air pressure is among the most important variables that affect atmospheric dynamics, and currently can only be measured by limited in-situ observations over oceans. Analyses show that with the proposed radar the errors in instantaneous (averaged) pressure estimates can be as low as approximately 5 millibars (approximately 1 millibar) under all weather conditions. With these sea level pressure measurements, the forecasts, analyses and understanding of these extreme events in both short and long time scales can be improved. Severe weathers, especially hurricanes, are listed as one of core areas that need improved observations and predictions in WCRP (World Climate Research Program) and NASA Decadal Survey (DS) and have major impacts on public safety and national security through disaster mitigation. Since the development of the DiBAR concept about a decade ago, our team has made substantial progress in advancing the concept. Our feasibility assessment clearly shows the potential of sea surface barometry using existing radar technologies. We have developed a DiBAR system design, fabricated a Prototype-DiBAR (P-DiBAR) for proof-of-concept, conducted lab, ground and airborne P-DiBAR tests. The flight test results are consistent with our instrumentation goals. Observational system simulation experiments for space DiBAR performance show substantial improvements in tropical storm predictions, not only for the hurricane track and position but also for the hurricane intensity. DiBAR measurements will lead us to an unprecedented level of the prediction and knowledge on tropical extreme rainfall weather and climate conditions.

Characterization and monitoring of the excavation damaged zone in fractured gneisses of the Roselend tunnel, French Alps

NASA Astrophysics Data System (ADS)

Wassermann, J.; Sabroux, J. C.; Pontreau, S.; Bondiguel, S.; Guillon, S.; Richon, P.; Pili, E.

2011-04-01

The Roselend dead-end tunnel was excavated in the last fifties by blasting in the Méraillet crystalline rock mass located on the shore of an artificial reservoir lake in the French Alps. Successive emptying and filling of the reservoir lake induce mechanical deformation of the rock mass. Thus, this tunnel is an exceptional place to study the evolution of the damaged zone (due to the excavation, and named EDZ) under a periodic mechanical or hydraulic loading. From the perspective of radioactive waste isolation in deep geological strata, the EDZ transport properties, and their evolution with time, are of major importance. The purpose of this study is, on the one hand, to quantify the transport properties of the EDZ of the Roselend tunnel through permeability measurements and drill core observations; on the other hand, to monitor the response of the EDZ to external solicitations via borehole pressure measurements. The air permeability has been deduced from pneumatic tests performed along several boreholes. The permeability profiles and the observation of drill cores lead to an estimation of the extent of the EDZ, of about 1 m around the tunnel. The response of the EDZ to barometric pumping has been observed through borehole pressure monitoring. Time-lag and attenuation of the barometric signal that propagates into the EDZ have been measured at a metric scale. The identification of potential time-lag and attenuation variations needs further investigations, the long time series of borehole pressure monitoring shows pressure increase probably due to percolating water during successive snow cover and thawing periods as observed in the Roselend area during winter.

A stochastic approach to noise modeling for barometric altimeters.

PubMed

Sabatini, Angelo Maria; Genovese, Vincenzo

2013-11-18

The question whether barometric altimeters can be applied to accurately track human motions is still debated, since their measurement performance are rather poor due to either coarse resolution or drifting behavior problems. As a step toward accurate short-time tracking of changes in height (up to few minutes), we develop a stochastic model that attempts to capture some statistical properties of the barometric altimeter noise. The barometric altimeter noise is decomposed in three components with different physical origin and properties: a deterministic time-varying mean, mainly correlated with global environment changes, and a first-order Gauss-Markov (GM) random process, mainly accounting for short-term, local environment changes, the effects of which are prominent, respectively, for long-time and short-time motion tracking; an uncorrelated random process, mainly due to wideband electronic noise, including quantization noise. Autoregressive-moving average (ARMA) system identification techniques are used to capture the correlation structure of the piecewise stationary GM component, and to estimate its standard deviation, together with the standard deviation of the uncorrelated component. M-point moving average filters used alone or in combination with whitening filters learnt from ARMA model parameters are further tested in few dynamic motion experiments and discussed for their capability of short-time tracking small-amplitude, low-frequency motions.

Applying spectral data analysis techniques to aquifer monitoring data in Belvoir Ranch, Wyoming

NASA Astrophysics Data System (ADS)

Gao, F.; He, S.; Zhang, Y.

2017-12-01

This study uses spectral data analysis techniques to estimate the hydraulic parameters from water level fluctuation due to tide effect and barometric effect. All water level data used in this study are collected in Belvoir Ranch, Wyoming. Tide effect can be not only observed in coastal areas, but also in inland confined aquifers. The force caused by changing positions of sun and moon affects not only ocean but also solid earth. The tide effect has an oscillatory pumping or injection sequence to the aquifer, and can be observed from dense water level monitoring. Belvoir Ranch data are collected once per hour, thus is dense enough to capture the tide effect. First, transforming de-trended data from temporal domain to frequency domain with Fourier transform method. Then, the storage coefficient can be estimated using Bredehoeft-Jacob model. After this, analyze the gain function, which expresses the amplification and attenuation of the output signal, and derive barometric efficiency. Next, find effective porosity with storage coefficient and barometric efficiency with Jacob's model. Finally, estimate aquifer transmissivity and hydraulic conductivity using Paul Hsieh's method. The estimated hydraulic parameters are compared with those from traditional pumping data estimation. This study proves that hydraulic parameter can be estimated by only analyze water level data in frequency domain. It has the advantages of low cost and environmental friendly, thus should be considered for future use of hydraulic parameter estimations.

A multiyear dust devil vortex survey using an automated search of pressure time series

NASA Astrophysics Data System (ADS)

Jackson, Brian; Lorenz, Ralph

2015-03-01

Dust devils occur in arid climates on the Earth and ubiquitously on Mars, where they likely dominate the supply of atmospheric dust and influence climate. Martian dust devils have been studied with a combination of orbiting and landed spacecraft, while most studies of terrestrial dust devils have involved manned monitoring of field sites, which can be costly both in time and personnel. As an alternative approach, we describe a multiyear in situ survey of terrestrial dust devils using pressure loggers deployed at El Dorado Playa in Nevada, USA, a site known for dust devil activity. Analogous to previous surveys for Martian dust devils, we conduct a posthoc analysis of the barometric data to search for putative dust devil pressure dips using a new automated detection algorithm. We investigate the completeness and false positive rates of our new algorithm and conduct several statistically robust analyses of the resulting population of dips. We also investigate possible seasonal, annual, and spatial variability of the putative dust devil dips, possible correlations with precipitation, and the influence of sample size on the derived population statistics. Our results suggest that large numbers of dips (>1000) collected over multiple seasons are probably required for accurate assessment of the underlying dust devil population. Correlating long-term barometric time series with other data streams (e.g., solar flux measurements from photovoltaic cells) can uniquely elucidate the natures and origins of dust devils, and accurately assessing their influence requires consideration of the full distribution of dust devil properties, rather than average values.

Multiphase, multicomponent flow and transport models for Nuclear Test-Ban Treaty monitoring and nuclear waste disposal applications

NASA Astrophysics Data System (ADS)

Jordan, Amy

Open challenges remain in using numerical models of subsurface flow and transport systems to make useful predictions related to nuclear waste storage and nonproliferation. The work presented here addresses the sensitivity of model results to unknown parameters, states, and processes, particularly uncertainties related to incorporating previously unrepresented processes (e.g., explosion-induced fracturing, hydrous mineral dehydration) into a subsurface flow and transport numerical simulator. The Finite Element Heat and Mass (FEHM) transfer code is used for all numerical models in this research. An experimental campaign intended to validate the predictive capability of numerical models that include the strongly coupled thermal, hydrological, and chemical processes in bedded salt is also presented. Underground nuclear explosions (UNEs) produce radionuclide gases that may seep to the surface over weeks to months. The estimated timing of gas arrival at the surface may be used to deploy personnel and equipment to the site of a suspected UNE, if allowed under the terms of the Comprehensive Nuclear Test-Ban Treaty. A model was developed using FEHM that considers barometrically pumped gas transport through a simplified fractured medium and was used to quantify the impact of uncertainties in hydrologic parameters (fracture aperture, matrix permeability, porosity, and saturation) and season of detonation on the timing of gas breakthrough. Numerical sensitivity analyses were performed for the case of a 1 kt UNE at a 400 m burial depth. Gas arrival time was found to be most affected by matrix permeability and fracture aperture. Gases having higher diffusivity were more sensitive to uncertainty in the rock properties. The effect of seasonality in the barometric pressure forcing was found to be important, with detonations in March the least likely to be detectable based on barometric data for Rainier Mesa, Nevada. Monte Carlo modeling was also used to predict the window of opportunity for Xe-133 detection from a 1 kt UNE at Rainier Mesa, with and without matching the model to SF6 and He-3 data from the 1993 Non Proliferation Experiment. Results from the data-blind Monte Carlo simulations were similar, but were biased towards earlier arrival time and less likely to show detectable Xe-133. The second study, also related to nuclear nonproliferation compliance, considered the effect of barometric pumping on predicted Xe-133 breakthrough time in a Monte Carlo framework. Barometric pumping of gas through explosion-fractured rock was investigated using a new sequentially-coupled hydrodynamic rock damage/gas transport model. Fracture networks for two rock types (granite and saturated tuff) and three depths of burial were integrated into a numerical model driven by surface pressure signals of differing amplitude and variability. Matrix porosity and maximum fracture aperture had the greatest impact on gas breakthrough time and window of opportunity for detection. Differences in model sensitivity for granite and tuff simulations highlight the importance of accurately simulating the fracture network. From Monte Carlo simulations using randomly generated hydrogeologic parameters, normalized probability of detection curves showed differences in optimal sampling time for granite and tuff. Granite breakthrough was earlier, as was breakthrough in realizations with greater variance of barometric pressure. Next, heat-generating nuclear waste (HGNW) disposal in bedded salt during the first two years after waste emplacement was explored using numerical simulations tied to experiments of hydrous mineral dehydration. Heating impure salt samples to temperatures of 265°C released water in amounts greater than 20% by mass of hydrous minerals and clays. Experimental data for water loss at several temperatures were averaged to produce a water source model that was then implemented in FEHM. Simulations using this dehydration model were used to predict temperature, moisture, and porosity after heating by 750W waste canisters, assuming hydrous mineral mass fractions from 0--10%. The formation of a three-phase heat pipe (with counter-circulation of vapor and brine) occurs as water vapor is driven away from the heat source, condenses, and flows back towards the heat source, leading to changes in porosity, permeability, temperature, saturation, and thermal conductivity of the backfill salt surrounding the waste canisters. Heat pipe formation depends on temperature, moisture availability and fluid mobility. In certain cases, dehydration of hydrous minerals provided sufficient additional moisture to push the system into a sustained heat pipe where simulations neglecting this process did not. A laboratory-scale experiment (˜1 m3) using granular salt was conducted to gain a better understanding of the complex coupled processes involved in liquid, vapor, and solid transport occurring around heated nuclear waste in crushed salt, which could be a mode of disposal for HGNW. The experiment was designed to study transport processes in the system that have not been satisfactorily quantified in prior work. Initial results from the experimental effort offer promising insights. (Abstract shortened by UMI.).

Venting test analysis using Jacob`s approximation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, K.B.

1996-03-01

There are many sites contaminated by volatile organic compounds (VOCs) in the US and worldwide. Several technologies are available for remediation of these sites, including excavation, pump and treat, biological treatment, air sparging, steam injection, bioventing, and soil vapor extraction (SVE). SVE is also known as soil venting or vacuum extraction. Field venting tests were conducted in alluvial sands residing between the water table and a clay layer. Flow rate, barometric pressure, and well-pressure data were recorded using pressure transmitters and a personal computer. Data were logged as frequently as every second during periods of rapid change in pressure. Testsmore » were conducted at various extraction rates. The data from several tests were analyzed concurrently by normalizing the well pressures with respect to extraction rate. The normalized pressures vary logarithmically with time and fall on one line allowing a single match of the Jacob approximation to all tests. Though the Jacob approximation was originally developed for hydraulic pump test analysis, it is now commonly used for venting test analysis. Only recently, however, has it been used to analyze several transient tests simultaneously. For the field venting tests conducted in the alluvial sands, the air permeability and effective porosity determined from the concurrent analysis are 8.2 {times} 10{sup {minus}7} cm{sup 2} and 20%, respectively.« less

Airborne Chlordane Contamination in Houses Treated for Termites at a Midwestern Air Force Base

DTIC Science & Technology

1981-02-01

to provide entry authorization. Inside air temperature and relative humidity were measured with a sling psychrometer at the time of sampling...of the houses had chlordane concentrations 21.0 Pg/m3. No correlation could be made between chlordane concentration and year of treatment except for...from 14.5 to 37.8 pg/m8, were found in houses treated in 1970. Correlation of chlordane concentration could not be made with barometric pressure

CRISTAPRESS: an optical cell for structure development in high-pressure crystallization.

PubMed

Boyer, S A E; Fournier, F E J; Gandin, Ch-A; Haudin, J-M

2014-01-01

An original optical high-pressure cell, named CRISTAPRESS, has been especially designed to investigate phase transitions of complex liquids, i.e., polymers, polymer blends, nano-composites, etc. The design of the cell is based on the optical properties of morphological entities through in situ light depolarizing microscopic observations. Pressure up to 200 MPa with a fine temperature control up to 300 °C can be applied. A striking advantage of this cell is the possibility to select the pressure transmitting medium that can be water, silicone oil, a fluid in the supercritical state, etc. The potential of the novel technique was demonstrated by carrying out time-resolved measurements during polymer crystallization induced by water pressure. These preliminary experimental investigations permit to discriminate the role of the barometric and thermal histories on the kinetics of polymer growth, as well as on the subsequent morphologies. It should lead to new reliable crystallization kinetics models.

A water balance model to estimate flow through the Old and Middle River corridor

USGS Publications Warehouse

Andrews, Stephen W.; Gross, Edward S.; Hutton, Paul H.

2016-01-01

We applied a water balance model to predict tidally averaged (subtidal) flows through the Old River and Middle River corridor in the Sacramento–San Joaquin Delta. We reviewed the dynamics that govern subtidal flows and water levels and adopted a simplified representation. In this water balance approach, we estimated ungaged flows as linear functions of known (or specified) flows. We assumed that subtidal storage within the control volume varies because of fortnightly variation in subtidal water level, Delta inflow, and barometric pressure. The water balance model effectively predicts subtidal flows and approaches the accuracy of a 1–D Delta hydrodynamic model. We explore the potential to improve the approach by representing more complex dynamics and identify possible future improvements.

Field determination of vertical permeability to air in the unsaturated zone

USGS Publications Warehouse

Weeks, Edwin P.

1978-01-01

The vertical permeability to air of layered materials in the unsaturated zone may be determined from air pressure data obtained at depth during a period when air pressure is changing at land surface. Such data may be obtained by monitoring barometric pressure with a microbarograph or surveying altimeter and simultaneously measuring down-hole pneumatic head differences in specially constructed piezometers. These data, coupled with air-filled porosity data from other sources, may be compared with the results of electric-analog or numerical solution of the one-dimensional diffusion equation to make a trial-and-error determination of the air permeability for each layer. The permeabilities to air may in turn be converted to equivalent hydraulic conductivity values if the materials are well drained, are permeable enough that the Klinkenberg effect is small, and are structurally unaffected by wetting. The method offers potential advantages over present methods to evaluate sites for artificial recharge by spreading; to evaluate ground-water pollution hazards from feedlots, sanitary landfills , and land irrigated with sewage effluent; and to evaluate sites for temporary storage of gas in the unsaturated zone. (Woodard-USGS)

ALT space shuttle barometric altimeter altitude analysis

NASA Technical Reports Server (NTRS)

Killen, R.

1978-01-01

The accuracy was analyzed of the barometric altimeters onboard the space shuttle orbiter. Altitude estimates from the air data systems including the operational instrumentation and the developmental flight instrumentation were obtained for each of the approach and landing test flights. By comparing the barometric altitude estimates to altitudes derived from radar tracking data filtered through a Kalman filter and fully corrected for atmospheric refraction, the errors in the barometric altitudes were shown to be 4 to 5 percent of the Kalman altitudes. By comparing the altitude determined from the true atmosphere derived from weather balloon data to the altitude determined from the U.S. Standard Atmosphere of 1962, it was determined that the assumption of the Standard Atmosphere equations contributes roughly 75 percent of the total error in the baro estimates. After correcting the barometric altitude estimates using an average summer model atmosphere computed for the average latitude of the space shuttle landing sites, the residual error in the altitude estimates was reduced to less than 373 feet. This corresponds to an error of less than 1.5 percent for altitudes above 4000 feet for all flights.

Influence of confining layers' heterogeneity on the barometric response functions in semi-confined aquifers

NASA Astrophysics Data System (ADS)

Redaelli, Marco; Perulero Serrano, Raul

2017-04-01

It has been shown that Barometric Response Functions (BRFs) can provide a useful tool for detecting the occurrence of highly conducive bodies which span across aquifer confining layers and can potentially give rise to pathways for pollutant migration (Hussein et al 2013, Odling et al 2015). Analytical models employed to estimate BRFs from geological system properties assume homogeneity within the aquifer and its confining layer. These assumptions are rarely satisfied in practice. Our study focusses on the impact on predicted BRFs of heterogeneous distribution of high conductivity geomaterials within the confining layer. The work is grounded on a suite of three-dimensional, transient numerical computations of groundwater flow in a confining layer-aquifer system for i) a perfectly homogeneous two-layer setting where a single highly conducive block is fully penetrating the confining layer and ii) a heterogeneous two-layer system where hydraulic conductivity in the confining layer is modelled as a stochastic process. Our numerical results are interpreted through a comparison against those associated with an analytical model which assumes system homogeneity. Monitoring points located in the middle of the modelled aquifer domain, mimicking screened boreholes in field conditions, are used to extract water level records. The output is used to obtain the corresponding BRFs (in terms of gain and phase components) and compared vis-a-vis the selected analytical solution. The results show a wide variety of BRF responses, especially in the gain component, which vary from almost confined to unconfined scenarios. Our simulations show that the BRFs are a viable tool to improve understanding of the degree of spatial continuity within low permeability heterogeneous geological materials such as glacial till which is frequently found overlying water bearing units across the UK and other localities worldwide. As such, it has the potential to improve groundwater vulnerability assessment protocols. The results are promising and support the merit of additional developments through, e.g., numerical Monte Carlo simulations which can be performed to extract meaningful statistical information on the nature of BRFs as a function of randomly heterogeneous confining layers. Keywords: groundwater vulnerability, numerical modeling, barometric response functions, semi-confined aquifers References Hussein M.E.A., Odling N.E. & Clark R.A. (2013). Borehole water level response to barometric pressure as an indicator of aquifer vulnerability, Water Resources Research, 49: 7102-7119. Odling N.E, Perulero Serrano R., Hussein M.E.A, Riva M. & Guadagnini A. (2015). Detecting the vulnerability of groundwater in semi-confined aquifers using barometric response functions, Journal of Hydrology, 520: 143-156.

Robert Boyle's landmark book of 1660 with the first experiments on rarified air.

PubMed

West, John B

2005-01-01

In 1660, Robert Boyle (1627-1691) published his landmark book New Experiments Physico-Mechanicall, Touching the Spring of the Air, and its Effects... in which he described the first controlled experiments of the effects of reducing the pressure of the air. Critical to this work was the development of an air pump by Boyle with Robert Hooke (1635-1703). For the first time, it was possible to observe physical and physiological processes at both normal and reduced barometric pressures. The air pump was described in detail, although the exact design of the critical piston is unclear. Boyle reported 43 separate experiments, which can conveniently be divided into 7 groups. The first experiments were on the "spring of the air," that is the pressure developed by the air when its volume was changed. Several experiments described the behavior of the barometer invented by Torricelli just 16 years before when it was introduced into the low-pressure chamber. The behavior of burning candles was discussed, although this emphasized early misunderstandings of the nature of combustion. There were some physiological observations, although these were later extended by Boyle and Hooke. The effects of the low pressure on such diverse physical phenomena as magnetism, sound propagation, behavior of a pendulum, evolution of gases from liquids, and the behavior of smoke were described. This classic book is brimming with enthusiasm and fresh ideas even for today and deserves to be better known.

AltitudeOmics: effect of reduced barometric pressure on detection of intrapulmonary shunt, pulmonary gas exchange efficiency, and total pulmonary resistance.

PubMed

Petrassi, Frank A; Davis, James T; Beasley, Kara M; Evero, Oghenero; Elliott, Jonathan E; Goodman, Randall D; Futral, Joel E; Subudhi, Andrew; Solano-Altamirano, J Manuel; Goldman, Saul; Roach, Robert C; Lovering, Andrew T

2018-05-01

Blood flow through intrapulmonary arteriovenous anastomoses (Q IPAVA ) occurs in healthy humans at rest and during exercise when breathing hypoxic gas mixtures at sea level and may be a source of right-to-left shunt. However, at high altitudes, Q IPAVA is reduced compared with sea level, as detected using transthoracic saline contrast echocardiography (TTSCE). It remains unknown whether the reduction in Q IPAVA (i.e., lower bubble scores) at high altitude is due to a reduction in bubble stability resulting from the lower barometric pressure (P B ) or represents an actual reduction in Q IPAVA . To this end, Q IPAVA , pulmonary artery systolic pressure (PASP), cardiac output (Q T ), and the alveolar-to-arterial oxygen difference (AaDO 2 ) were assessed at rest and during exercise (70-190 W) in the field (5,260 m) and in the laboratory (1,668 m) during four conditions: normobaric normoxia (NN; [Formula: see text] = 121 mmHg, P B  = 625 mmHg; n = 8), normobaric hypoxia (NH; [Formula: see text] = 76 mmHg, P B  = 625 mmHg; n = 7), hypobaric normoxia (HN; [Formula: see text] = 121 mmHg, P B  = 410 mmHg; n = 8), and hypobaric hypoxia (HH; [Formula: see text] = 75 mmHg, P B  = 410 mmHg; n = 7). We hypothesized Q IPAVA would be reduced during exercise in isooxic hypobaria compared with normobaria and that the AaDO 2 would be reduced in isooxic hypobaria compared with normobaria. Bubble scores were greater in normobaric conditions, but the AaDO 2 was similar in both isooxic hypobaria and normobaria. Total pulmonary resistance (PASP/Q T ) was elevated in HN and HH. Using mathematical modeling, we found no effect of hypobaria on bubble dissolution time within the pulmonary transit times under consideration (<5 s). Consequently, our data suggest an effect of hypobaria alone on pulmonary blood flow. NEW & NOTEWORTHY Blood flow through intrapulmonary arteriovenous anastomoses, detected by transthoracic saline contrast echocardiography, was reduced during exercise in acute hypobaria compared with normobaria, independent of oxygen tension, whereas pulmonary gas exchange efficiency was unaffected. Modeling the effect(s) of reduced air density on contrast bubble lifetime did not result in a significantly reduced contrast stability. Interestingly, total pulmonary resistance was increased by hypobaria, independent of oxygen tension, suggesting that pulmonary blood flow may be changed by hypobaria.

Analysis of Flight of Near-Space Balloon

NASA Astrophysics Data System (ADS)

Miller, Zech; Evans, Austin; Seyfert, James; Leadlove, Kyle; Gumina, Kaitlyn; Martell, Eric

2015-04-01

In December 2014, the Electronics class at Millikin University launched a balloon designed to travel into the near-space region of the atmosphere. The balloon was equipped with an instrumentation package including a camera, accelerometer, barometric pressure sensor, temperature probes, as well as a system for tracking using an Automatic Packet Reporting System (APRS). The balloon was launched from Decatur, IL, and landed in Marysville, OH, nearly 320 miles away. The students then analyzed the data from the flight and compared results to expectations.

A Uniform Fault Zone Diffusivity Structure in the Simi Valley Based on Water Level Tidal and Barometric Response

NASA Astrophysics Data System (ADS)

Xue, L.; Brodsky, E. E.; Allègre, V.; Parker, B. L.; Cherry, J. A.

2016-12-01

Water levels inside conventional water wells can tap an artesian aquifer response to pressure head disturbances caused by the Earth tides and surface atmospheric loading. The fluctuation of water levels can measure the hydrogeologic properties of the formation surrounding these wells. Specifically, the amplitude of water level oscillation is determined by formation specific storage, and the phase shift between the water level oscillation and the pressure head disturbance is determined by formation permeability. We utilized 36 wells completed in fractured, interbedded sandstone of turbidite origin in an upland area of southern California to measure the in-situ hydrogeologic properties by combining the water level tidal and barometric responses. This site experiences north-south shortening and it has groups of NE-SW and east-west conjugate faults. The site has been intensively characterized and monitored hydrologically since the 1980's because of the groundwater contamination. Hence, this study provides a good opportunity to measure the in-situ hydrogeologic properties for comparison to other test types and scales. Most of the observed water level tidal responses have a lead phase response, which cannot be interpreted either by the water level response in a confined aquifer or the water level response in an unconfined aquifer. To interpret these observations, we utilized the water level response in a partially confined aquifer, resulting in both positive and negative phase information when fully considering all the observations. Due to the different mechanisms for tidal versus barometric water level responses, the combination can give better constraints on the inverted hydrologic properties. The range of the measured permeability is 10-15-10-13 m2 and the range of the specific storage is 10-7-10-5 1/m. The resulting diffusivity is within 10-2-10-1 m2/s which is relatively uniform. This indicates the fault damages in the site are relatively homogeneous at the scale of measurement and there is no major fault-guided hydrogeological channel at the site. Such homogenous by fault zone damage is possible in a region of multiple strands and copious secondary faulting.

Barometric response functions from borehole water level records and quantification of aquifer vulnerability

NASA Astrophysics Data System (ADS)

Odling, N. E.; Serrano, R. P.; Hussein, M.; Guadagnini, A.; Riva, M.

2013-12-01

In confined and semi-confined aquifers, borehole water levels respond to fluctuations in barometric pressure and this response can be used to estimate the properties of aquifer confining layers. We use this response as indicator of groundwater vulnerability for the semi-confined Chalk aquifer in East Yorkshire, UK. Time series data of borehole water levels are corrected for Earth tides and recharge, and barometric response functions (BRFs) estimated using cross-spectral deconvolution-averaging techniques. The resulting BRFs are fitted using a theoretical model of the BRF gain and phase for a semi-confined aquifer (Rojstaczer, 1988) to obtain confining layer properties. For all of the boreholes, non-zero hydraulic diffusivities for the confining layer were found indicating that the aquifer is semi-confined. A ';characteristic time scale' based on the hydraulic and pneumatic diffusivities of the confining layer is introduced as a measure of the degree of aquifer confinement and therefore groundwater vulnerability. The analytical model assumes that the confining layer and aquifer are homogeneous. However, in nature, confining layers are heterogeneous and groundwater vulnerability dominated by the presence of high diffusivity, high flow pathways through the confining layer to the aquifer. A transient numerical model (MODFLOW) was constructed to test the impact of such heterogeneities on the BRF. In the model, an observed barometric pressure time series is used as a boundary condition applied to the upper surface of the top unit of the model (representing the confining layer) and BRFs determined from the time series of model heads in the bottom unit (representing the aquifer). The results from a numerical model with a homogeneous confining layer were found to accurately reproduce the BRFs from a modified version of the analytical model. The introduction of a localized, high diffusive block in the confining layer was found to modify the BRF, reducing the gain amplitude while having limited impact on the phase. It was found that the BRF reflects the presence of a fully penetrating, high diffusivity heterogeneity up to several hundred meters distant from the observation borehole, and shows little sensitivity to the heterogeneity's horizontal dimension. Heterogeneities that are 50% partially penetrating do not significantly impact on the BRF and 90% penetrating heterogeneities can only be detected when large and close to the observation borehole. These results show that BRF gain may be particularly useful in detecting the presence of fully penetrating heterogeneities of high diffusivity within confining layers that potentially enhance groundwater vulnerability. This research has been funded in part through the EU ITN ';IMVUL' (PITN-GA-2008-212298). Reference: Rojstaczer, S. (1988) Determination of fluid-flow properties from the response of water levels in wells to atmospheric loading, Water Resources Research, 24(11), 1927-1938.

In-Flight Hypoxemia in a Tracheostomy-Dependent Infant

PubMed Central

Cropsey, Christopher

2017-01-01

Millions of passengers board commercial flights every year. Healthcare providers are often called upon to treat other passengers during in-flight emergencies. The case presented involves an anesthesia resident treating a tracheostomy-dependent infant who developed hypoxemia on a domestic flight. The patient had an underlying congenital muscular disorder and was mechanically ventilated while at altitude. Although pressurized, cabin barometric pressure while at altitude is less than at sea level. Due to this environment patients with underlying pulmonary or cardiac pathology might not be able to tolerate commercial flight. The Federal Aviation Administration (FAA) has mandated a specific set of medical supplies be present on all domestic flights in addition to legislature protecting “Good Samaritan” providers. PMID:28348895

Nasal variation in relation to high-altitude adaptations among Tibetans and Andeans.

PubMed

Butaric, Lauren N; Klocke, Ross P

2018-05-01

High-altitude (>2500 m) populations face several pressures, including hypoxia and cold-dry air, resulting in greater respiratory demand to obtain more oxygen and condition inspired air. While cardiovascular and pulmonary adaptations to high-altitude hypoxia have been extensively studied, adaptations of upper-respiratory structures, e.g., nasal cavity, remain untested. This study investigates whether nasal morphology presents adaptations to hypoxic (larger noses) and/or cold-dry (tall/narrow noses) conditions among high-altitude samples. CT scans of two high- and four low-altitude samples from diverse climates were collected (n = 130): high-altitude Tibetans and Peruvians; low-altitude Peruvians, Southern Chinese (temperate), Mongolian-Buriats (cold-dry), and Southeast Asians (hot-wet). Facial and nasal distances were calculated from 3D landmarks placed on digitally-modeled crania. Temperature, precipitation, and barometric pressure data were also obtained. Principal components analysis and analyses of variance primarily indicate size-related differences among the cold-dry (Mongolian-Buriats) and hot-wet (Southeast Asians) adapted groups. Two-block partial least squares (PLS) analysis show weak relationships between size-standardized nasal dimensions and environmental variables. However, among PLS1 (85.90% of covariance), Tibetans display relatively larger nasal cavities related to lower temperatures and barometric pressure; regression analyses also indicate high-altitude Tibetans possess relatively larger internal nasal breadths and heights for their facial size. Overall, nasal differences relate to climate among the cold-dry and hot-wet groups. Specific nasal adaptations were not identified among either Peruvian group, perhaps due to their relatively recent migration history and population structure. However, high-altitude Tibetans seem to exhibit a compromise in nasal morphology, serving in increased oxygen uptake, and air-conditioning processes. © 2018 Wiley Periodicals, Inc.

Gasometer: An inexpensive device for continuous monitoring of dissolved gases and supersaturation

USGS Publications Warehouse

Bouck, G.R.

1982-01-01

The “gasometer” is a device that measures differential dissolved-gas pressures (δP) in water relative to barometric pressure (as does the “Weiss saturometer”), but operates continuously without human attention. The gasometer can be plumbed into a water-supply system and requires 8 liters/minute of water or more at 60 kilopascals. The gasometer's surfaces are nontoxic, and flow-through water can be used for fish culture. The gasometer may be connected to a small submersible pump and operated as a portable unit. The gasometer can activate an alarm system and thus protect fish from hyperbaric (supersaturation) or hypobaric gas pressures (usually due to low dissolved oxygen). Instructions are included for calculating and reporting data including the pressure and saturation of individual gases. Construction and performance standards are given for the gasometer. Occasional cleaning is required to remove biofouling from the gas-permeable tubing.PDF

Changes in entrapped gas content and hydraulic conductivity with pressure.

PubMed

Marinas, Maricris; Roy, James W; Smith, James E

2013-01-01

Water table fluctuations continuously introduce entrapped air bubbles into the otherwise saturated capillary fringe and groundwater zone, which reduces the effective (quasi-saturated) hydraulic conductivity, K(quasi), thus impacting groundwater flow, aquifer recharge and solute and contaminant transport. These entrapped gases will be susceptible to compression or expansion with changes in water pressure, as would be expected with water table (and barometric pressure) fluctuations. Here we undertake laboratory experiments using sand-packed columns to quantify the effect of water table changes of up to 250 cm on the entrapped gas content and the quasi-saturated hydraulic conductivity, and discuss our ability to account for these mechanisms in ground water models. Initial entrapped air contents ranged between 0.080 and 0.158, with a corresponding K(quasi) ranging between 2 and 6 times lower compared to the K(s) value. The application of 250 cm of water pressure caused an 18% to 26% reduction in the entrapped air content, resulting in an increase in K(quasi) by 1.16 to 1.57 times compared to its initial (0 cm water pressure) value. The change in entrapped air content measured at pressure step intervals of 50 cm, was essentially linear, and could be modeled according to the ideal gas law. Meanwhile, the changes in K(quasi) with compression-expansion of the bubbles because of pressure changes could be adequately captured with several current hydraulic conductivity models. © Ground Water 2012 and © Her Majesty the Queen in Right of Canada 2012. Ground Water © 2012, National Ground Water Association.

Freezing and frostbite on mount everest: new insights into wind chill and freezing times at extreme altitude.

PubMed

Moore, G W K; Semple, J L

2011-01-01

Cold injury is an acknowledged risk factor for those who venture into high altitude regions. There is, however, little quantitative information on this risk that can be used to implement mitigation strategies. Here we provide the first characterization of the risk of cold injury near the summit of Mount Everest. This is accomplished through the application of a meteorological dataset that has been demonstrated to characterize conditions in the region as inputs to new parameterizations of wind chill equivalent temperature (WCT) and facial frostbite time (FFT). Throughout the year, the typical WCT near the summit of Everest is always <-30°C, and the typical FFT is always less than 20 min. During the spring climbing season, WCTs of -50°C and FFTs of 5 min are typical; during severe storms, they approach -60°C and 1 min, respectively; values typically found during the winter. Further, we show that the summit barometric pressure is an excellent predictor of summit WCT and FFT. Our results provide the first quantitative characterization of the risk of cold injury on Mount Everest and also allow for the possibility of using barometric pressure, an easily observed parameter, in real time to characterize this risk and to implement mitigation strategies. The results also provide additional confirmation as to the extreme environment experienced by those attempting to summit Mount Everest and other high mountains.

Hazardous indoor CO2 concentrations in volcanic environments.

PubMed

Viveiros, Fátima; Gaspar, João L; Ferreira, Teresa; Silva, Catarina

2016-07-01

Carbon dioxide is one of the main soil gases released silently and permanently in diffuse degassing areas, both in volcanic and non-volcanic zones. In the volcanic islands of the Azores (Portugal) several villages are located over diffuse degassing areas. Lethal indoor CO2 concentrations (higher than 10 vol %) were measured in a shelter located at Furnas village, inside the caldera of the quiescent Furnas Volcano (S. Miguel Island). Hazardous CO2 concentrations were detected not only underground, but also at the ground floor level. Multivariate regression analysis was applied to the CO2 and environmental time series recorded between April 2008 and March 2010 at Furnas village. The results show that about 30% of the indoor CO2 variation is explained by environmental variables, namely barometric pressure, soil water content and wind speed. The highest indoor CO2 concentrations were recorded during bad weather conditions, characterized by low barometric pressure together with rainfall periods and high wind speed. In addition to the spike-like changes observed on the CO2 time series, long-term oscillations were also identified and appeared to represent seasonal variations. In fact, indoor CO2 concentrations were higher during winter period when compared to the dry summer months. Considering the permanent emission of CO2 in various volcanic regions of the world, CO2 hazard maps are crucial and need to be accounted by the land-use planners and authorities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Selected meteorological and micrometeorological data for an arid site near Beatty, Nye County, Nevada, calendar year 1992

USGS Publications Warehouse

Wood, James L.

1996-01-01

il-heat-flux data were collected at a study site adjacent to a low-level radioactive-waste burial facility near Beatty, Nevada, for calendar year 1992. Data were collected in support of ongoing studies to estimate the potential for downward movement of radionuclides into the unsaturated sediments beneath waste-burial trenches at the arid facility. Data collected for the whole year include air temperature, relative humidity, vapor pressure, incident solar radiation, windspeed, wind direction, barometric pressure, and precipitation. Net radiation, soil temperature, and soil-heat flux data also were collected for part of the year. The data are summarized in tables and graphs.Instrumentation used at the site is discussed. The discussion includes the type, reported accuracy, and the mounting height of each sensor.During 1992, the hourly and 20-minute mean air temperatures ranged from -8.6 degrees Celsius, in January, to 42.3 degrees Celsius, in July. Hourly and 20-minute mean relative humidity ranged from 2 percent to 100 percent. Hourly and 20-minute mean vapor pressures ranged from 0.07 to 2.47 kilopascals. Daily maximum incident solar radiation values ranged from 115 to 1,021 watts per square meter. Daily maximum net radiation values ranged from 195 to 632 watts per square meter. Daily mean windspeed ranged from 0.6 to 8.1 meters per second. Wind direction was primarily from the northwest in fall, winter, and spring and was from the southeast, southwest, or northwest during the summer. Barometric pressures ranged from 100.16 kilopascals to 103.38 kilopascals. Total precipitation for 1992 was 165.3 millimeters, with more than 50 percent in February and March. Daily mean soil temperatures at a depth from 2 to 6 centimeters ranged from 10.7 to 39.1 degrees Celsius between June and October. Daily mean soil-heat flux at a dep*h of 8 centimeters ranged from -13.4 to 12.2 watts per square meter during the same period.

Climate-driven polar motion

NASA Astrophysics Data System (ADS)

Celaya, Michael A.; Wahr, John M.; Bryan, Frank O.

1999-06-01

The output of a coupled climate system model provides a synthetic climate record with temporal and spatial coverage not attainable with observational data, allowing evaluation of climatic excitation of polar motion on timescales of months to decades. Analysis of the geodetically inferred Chandler excitation power shows that it has fluctuated by up to 90% since 1900 and that it has characteristics representative of a stationary Gaussian process. Our model-predicted climate excitation of the Chandler wobble also exhibits variable power comparable to the observed. Ocean currents and bottom pressure shifts acting together can alone drive the 14-month wobble. The same is true of the excitation generated by the combined effects of barometric pressure and winds. The oceanic and atmospheric contributions are this large because of a relatively high degree of constructive interference between seafloor pressure and currents and between atmospheric pressure and winds. In contrast, excitation by the redistribution of water on land appears largely insignificant. Not surprisingly, the full climate effect is even more capable of driving the wobble than the effects of the oceans or atmosphere alone are. Our match to the observed annual excitation is also improved, by about 17%, over previous estimates made with historical climate data. Efforts to explain the 30-year Markowitz wobble meet with less success. Even so, at periods ranging from months to decades, excitation generated by a model of a coupled climate system makes a close approximation to the amplitude of what is geodetically observed.

SU-E-T-87: A TG-100 Approach for Quality Improvement of Associated Dosimetry Equipment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manger, R; Pawlicki, T; Kim, G

2015-06-15

Purpose: Dosimetry protocols devote so much time to the discussion of ionization chamber choice, use and performance that is easy to forget about the importance of the associated dosimetry equipment (ADE) in radiation dosimetry - barometer, thermometer, electrometer, phantoms, triaxial cables, etc. Improper use and inaccuracy of these devices may significantly affect the accuracy of radiation dosimetry. The purpose of this study is to evaluate the risk factors in the monthly output dosimetry procedure and recommend corrective actions using a TG-100 approach. Methods: A failure mode and effects analysis (FMEA) of the monthly linac output check procedure was performed tomore » determine which steps and failure modes carried the greatest risk. In addition, a fault tree analysis (FTA) was performed to expand the initial list of failure modes making sure that none were overlooked. After determining the failure modes with the highest risk priority numbers (RPNs), 11 physicists were asked to score corrective actions based on their ease of implementation and potential impact. The results were aggregated into an impact map to determine the implementable corrective actions. Results: Three of the top five failure modes were related to the thermometer and barometer. The two highest RPN-ranked failure modes were related to barometric pressure inaccuracy due to their high lack-of-detectability scores. Six corrective actions were proposed to address barometric pressure inaccuracy, and the survey results found the following two corrective actions to be implementable: 1) send the barometer for recalibration at a calibration laboratory and 2) check the barometer accuracy against the local airport and correct for elevation. Conclusion: An FMEA on monthly output measurements displayed the importance of ADE for accurate radiation dosimetry. When brainstorming for corrective actions, an impact map is helpful for visualizing the overall impact versus the ease of implementation.« less

Gas Transport through Fractured Rock near the U20az Borehole, Pahute Mesa, Nevada.

NASA Astrophysics Data System (ADS)

Rockhold, M.; Lowrey, J. D.; Kirkham, R.; Olsen, K.; Waichler, S.; White, M. D.; Wurstner White, S.

2017-12-01

Field experiments were performed in 2012-13 and 2016-17 at the U-20az testbed at the Nevada National Security Site to develop and evaluate capabilities for monitoring and modeling noble gas transport associated with underground nuclear explosions (UNE). Experiments were performed by injecting both chemical (CF2BR2, SF6) and radioactive (37Ar, 127Xe) gas species into the deep subsurface at this legacy UNE site and monitoring the breakthrough of the gases at different locations on or near the ground surface. Gas pressures were also monitored in both the chimney and at ground surface. Field experiments were modeled using the parallel, non-isothermal, two-phase flow and transport simulator, STOMP-GT. A site conceptual-numerical model was developed from a geologic framework model, and using a dual-porosity/permeability model for the constitutive relative permeability-saturation-capillary pressure relations of the fractured rock units. Comparisons of observed and simulated gas species concentrations show that diffusion is a highly effective transport mechanism under ambient conditions in the water-unsaturated fractured rock. Over-pressurization of the cavity during one of the field campaigns, and barometric pressure fluctuations are shown to result in enhanced gas transport by advection through fractures.

2009 weather and aeolian sand-transport data from the Colorado River corridor, Grand Canyon, Arizona

USGS Publications Warehouse

Draut, Amy E.; Sondossi, Hoda A.; Dealy, Timothy P.; Hazel, Joseph E.; Fairley, Helen C.; Brown, Christopher R.

2010-01-01

This report presents measurements of weather parameters and aeolian sand transport made in 2009 near selected archeological sites in the Colorado River corridor through Grand Canyon, Ariz. The quantitative methods and data discussed here form a basis for monitoring ecosystem processes that affect archeological-site stability. Combined with forthcoming work to evaluate landscape evolution at nearby archeological sites, these data can be used to document the relation between physical processes, including weather and aeolian sand transport, and their effects on the physical integrity of archeological sites. Data collected in 2009 reveal event- and seasonal-scale variations in rainfall, wind, temperature, humidity, and barometric pressure. Broad seasonal changes in aeolian sediment flux are also apparent at most study sites. Differences in weather patterns between 2008 and 2009 included an earlier spring windy season, greater spring precipitation even though 2009 annual rainfall totals were in general substantially lower than in 2008, and earlier onset of the reduced diurnal barometric-pressure fluctuations commonly associated with summer monsoon conditions. Weather patterns in middle to late 2009 were apparently affected by a transition of the ENSO cycle from a neutral phase to the El Ni?o phase. The continuation of monitoring that began in 2007, and installation of additional equipment at several new sites in early 2008, allowed evaluation of the effects of the March 2008 high-flow experiment (HFE) on aeolian sand transport. As reported earlier, at 2 of the 9 sites studied, spring and summer winds in 2008 reworked the HFE sandbars to form new aeolian dunes, where sand moved inland toward larger, well-established dune fields. Observations in 2009 showed that farther inland migration of the dune at one of those two sites is likely inhibited by vegetation. At the other location, the new aeolian dune form was found to have moved 10 m inland toward older, well-established dunes during 2009, resulting in landward transport of several hundred cubic meters of new sand upslope and above the elevation reached by the peak HFE water level.

Stratus 10: Tenth Setting of the Stratus Ocean Reference Station. Cruise RB-10-01 January 2 - January 30, 2010 Charleston, South Carolina - Valparaiso, Chile

DTIC Science & Technology

2010-05-01

data. Passed Florida Keys, turned south and crossed the Loop current. Swell from the west, choppy sea, cloudy then clearing in evening. Fire alarm...yr): 2 W/m2 (Colbo and Weller, 2009). Measurement is formed from one single snapshot each minute. 7) Barometric pressure Heise DXD ( Dresser ...have been crossing the ridge there because of a gap in the topography (Figures 5-9 and 5-13). A Seabeam survey was also done in anticipation of use

Geographically distributed environmental sensor system

DOEpatents

French, Patrick; Veatch, Brad; O'Connor, Mike

2006-10-03

The present invention is directed to a sensor network that includes a number of sensor units and a base unit. The base station operates in a network discovery mode (in which network topology information is collected) in a data polling mode (in which sensed information is collected from selected sensory units). Each of the sensor units can include a number of features, including an anemometer, a rain gauge, a compass, a GPS receiver, a barometric pressure sensor, an air temperature sensor, a humidity sensor, a level, and a radiant temperature sensor.

Meteorologic factors and subjective sleep continuity: a preliminary evaluation

NASA Astrophysics Data System (ADS)

Pandey, Juhi; Grandner, Michael; Crittenden, Crista; Smith, Michael T.; Perlis, Michael L.

2005-01-01

Little research has been undertaken to evaluate whether environmental factors other than bright light influence the individual’s ability to initiate and maintain sleep. In the present analyses, nine meteorologic variables were evaluated for their possible relationship to self-reported sleep continuity in a sample of 43 subjects over a period of 105 days. In this preliminary analysis, high barometric pressure, low precipitation, and lower temperatures were significantly correlated with good sleep continuity. Interestingly, ambient light and lunar phase were not found to be strongly associated sleep diary measures.

The effect of hyperbaric conditions on olfactory functions.

PubMed

Ay, Hakan; Salihoglu, Murat; Altundag, Aytug; Tekeli, Hakan; Memis, Ali; Cayonu, Melih

2014-01-01

The aim of this study was to investigate the effect of increased atmospheric pressure (AP) on olfactory function. The present study included 40 healthy volunteers with no history of chronic rhinosinusitis and nasal polyposis. The experimental procedure consisted of two episodes: (a) baseline episode, with normal AP; 1 absolute atmosphere (atm abs) in a test room at sea level; (b) experimental episode, increased level of AP; 2.4 atm abs in the hyperbaric chamber. Sino-nasal outcome test-20, Trail Making Test A and olfactory testing were performed in each episodes. The study group consisted of 23 men (57.5%) and 17 women (42.5%); the mean age of the study population was 38.7 +/- 9 years (range 23-58 years). The current investigation produced two major findings: (1) the mean of odor threshold scores was significantly increased in the hyperbaric condition when compared to the normobaric condition; (2) rather, there was no significant change in odor discrimination and identification scores in the hyperbaric condition. Based on two measurements taken at two different barometric pressures and the same temperature and relative humidity, this study suggests that odor threshold scores increase under hyperbaric conditions.

Examining Changes in Radioxenon Isotope Activity Ratios during Subsurface Transport

NASA Astrophysics Data System (ADS)

Annewandter, R.

2013-12-01

The Non-Proliferation Experiment (NPE) has demonstrated and modelled the usefulness of barometric pumping induced soil gas sampling during On-Site inspections. Gas transport has been widely studied with different numerical codes. However, gas transport of all radioxenons in the post-detonation regime and their possible fractionation is still neglected in the open literature. Atmospheric concentrations of the radioxenons Xe-135, Xe-133m, Xe-133 and Xe-131m can be used to discriminate between civilian releases (nuclear power plants or medical isotope facilities), and nuclear explosion sources. It is based on the isotopic activity ratio method. Yet it is not clear whether subsurface migration of the radioxenons, with eventual release into the atmosphere, can affect the activity ratios due to fractionation. Fractionation can be caused by different diffusivities due to mass differences between the radioxenons. A previous study showed surface arrival time of a chemically inert gaseous tracer is affected by its diffusivity. They observed detectable amount for SF6 50 days after detonation and 375 days for He-3. They predict 50 and 80 days for Xe-133 and Ar-37 respectively. Cyclical changes in atmospheric pressure can drive subsurface gas transport. This barometric pumping phenomenon causes an oscillatoric flow in upward trending fractures which, combined with diffusion into the porous matrix, leads to a net transport of gaseous components - a ratcheting effect. We use a general purpose reservoir simulator (Complex System Modelling Platform, CSMP++) which has been applied in a range of fields such as deep geothermal systems, three-phase black oil simulations , fracture propagation in fractured, porous media, Navier-Stokes pore-scale modelling among others. It is specifically designed to account for structurally complex geologic situation of fractured, porous media. Parabolic differential equations are solved by a continuous Galerkin finite-element method, hyperbolic differential equations by a complementary finite volume method. The parabolic and hyperbolic problem can be solved separately using the operator-splitting method (Implicit Pressure Explicit Saturation, IMPES). The resulting system of linear equations is solved by the algebraic multigrid library SAMG, developed at the Fraunhofer Institute for Algorithms and Scientific Computing. CSMP++ is developed at Montan University of Leoben, ETH Zuerich, Imperial College London and Heriot-Watt University in Edinburgh. To date, there has been no research investigating how subsurface transport impacts isotope activity ratios. The isotopic activity ratio method can be used to discriminate between civil release or nuclear explosion sources. This study examines possible fractionation of Xe-135, Xe-133m, Xe-133, Xe-131m during barometric pumping-driven subsurface migration, which can affect surface arrival times and isotopic activity ratios. Surface arrival times for the Noble gases Kr-81, Kr-85 and Ar-39 are also calculated.

Micrometeorological, evapotranspiration, and soil-moisture data at the Amargosa Desert Research site in Nye County near Beatty, Nevada, 2006-11

USGS Publications Warehouse

Arthur, Jonathan M.; Johnson, Michael J.; Mayers, C. Justin; Andraski, Brian J.

2012-11-13

This report describes micrometeorological, evapotranspiration, and soil-moisture data collected since 2006 at the Amargosa Desert Research Site adjacent to a low-level radio-active waste and hazardous chemical waste facility near Beatty, Nevada. Micrometeorological data include precipitation, solar radiation, net radiation, air temperature, relative humidity, saturated and ambient vapor pressure, wind speed and direction, barometric pressure, near-surface soil temperature, soil-heat flux, and soil-water content. Evapotranspiration (ET) data include latent-heat flux, sensible-heat flux, net radiation, soil-heat flux, soil temperature, air temperature, vapor pressure, and other principal energy-budget data. Soil-moisture data include periodic measurements of volumetric water-content at experimental sites that represent vegetated native soil, devegetated native soil, and simulated waste disposal trenches - maximum measurement depths range from 5.25 to 29.25 meters. All data are compiled in electronic spreadsheets that are included with this report.

Considerations for the head-injured air-evacuated patient: a case report of frontal sinus fracture and review of the literature.

PubMed

Helling, Eric; McKinlay, Alex J

2005-07-01

Head and neck injuries are not uncommon in combat environments and may be increasing due to survivable injuries from the use of kevlar helmets and body armor. With the current capability of rapid evacuation from the battlefield, acutely injured patients with frontal sinus injuries may undergo further barometric challenges. Proper care during transport can prevent the occurrence of secondary injury (increased intracranial pressure, tension pneumocephalus) that would complicate the patient's management at the next level of care. Management principles (importance of low-level flight/pressurized cabin, preflight use of decongestants, avoidance of valsalva, and ability to manage complications either procedurally or by landing) are reviewed. In addition, we propose a simple mechanism for pressure equilibration of a compromised frontal sinus during air evacuation using an angiocatheter placed through the wound before closure.

Rotating pressure measurement system using an on board calibration standard

NASA Technical Reports Server (NTRS)

Senyitko, Richard G.; Blumenthal, Philip Z.; Freedman, Robert J.

1991-01-01

A computer-controlled multichannel pressure measurement system was developed to acquire detailed flow field measurements on board the Large Low Speed Centrifugal Compressor Research Facility at the NASA Lewis Research Center. A pneumatic slip ring seal assembly is used to transfer calibration pressures to a reference standard transducer on board the compressor rotor in order to measure very low differential pressures with the high accuracy required. A unique data acquisition system was designed and built to convert the analog signal from the reference transducer to the variable frequency required by the multichannel pressure measurement system and also to provide an output for temperature control of the reference transducer. The system also monitors changes in test cell barometric pressure and rotating seal leakage and provides an on screen warning to the operator if limits are exceeded. The methods used for the selection and testing of the the reference transducer are discussed, and the data acquisition system hardware and software design are described. The calculated and experimental data for the system measurement accuracy are also presented.

Weather And Death On Mount Everest: An Analysis Of The Into Thin Air Storm.

NASA Astrophysics Data System (ADS)

Moore, G. W. K.; Semple, John L.

2006-04-01

Scientific interest in Mount Everest has been largely focused on the physiology of hypoxia caused by the summit's low barometric pressure. Although weather is recognized as a significant risk for climbers on the mountain, it has not been extensively studied. In this paper, we reconstruct the meteorological conditions associated with the deadly outbreak of high-impact weather on Mount Everest that occurred in May 1996 and was the subject of the best-selling book Into Thin Air. The authors show that during this event, two jet streaks—an upper-level short-wave trough and an intrusion of stratospheric air into the upper troposphere—were present in the vicinity of Mount Everest. Meanwhile, in the lower troposphere, there was convergence of water vapor transport from both the Arabian Sea and the Bay of Bengal into the region to the south of Mount Everest. The authors propose that the ageostrophic circulation associated with the upper-level features resulted in a region of large-scale ascent near Mount Everest that, in combination with the anomalous availability of moisture in the region, triggered convective activity. The resulting high-impact weather trapped over 20 climbers on Mount Everest's exposed upper slopes leading to the deaths of 8. These synoptic-scale characteristics provide some expectation of predicting life-threatening high-altitude storms in the Himalayas. In addition, the authors argue that the falling barometric pressure and the presence of ozone-rich stratospheric air that occurred near the summit of Mount Everest during this event could have shifted a coping climber from a state of brittle tolerance to physiological distress.

Handheld chemiresistive gas sensor readout system

NASA Astrophysics Data System (ADS)

Joubert, Trudi-Heleen; du Toit, Jurie; Mkwakikunga, Bonex; Bosscha, Peter

2016-02-01

Low-cost and non-invasive diabetes diagnosis is increasingly important [1], and this paper presents a handheld readout system for chemiresistive gas sensors in a breath acetone diagnostic application. The sensor contains reference and detection devices, used for the detection of gas concentration. Fabrication is by dropcasting a metaloxide nanowire solution onto gold interdigitated electrodes, which had been manufactured on silicon. The resulting layer is a wide bandgap n-type semiconductor material sensitive to acetone, producing a change in resistance between the electrode terminals [2]. Chemiresistive sensors typically require temperatures of 300-500 °C, while variation of sensing temperature is also employed for selective gas detection. The nano-structured functional material requires low temperatures due to large surface area, but heating is still required for acceptable recovery kinetics. Furthermore, UV illumination improves the sensor recovery [3], and is implemented in this system. Sensor resistances range from 100 Ω to 50 MΩ, while the sensor response time require a sampling frequency of 10Hz. Sensor resistance depends on temperature, humidity, and barometric pressure. The GE CC2A23 temperature sensor is used over a range of -10°C to 60°C, the Honeywell HIH5031 humidity sensor operates up to 85% over this temperature range, and the LPS331AP barometric pressure sensor measures up to 1.25 bar. Honeywell AWM43300V air flow sensors monitor the flow rate up to 1000 sccm. An LCD screen displays all the sensor data, as well as real time date and time, while all measurements are also logged in CSV-format. The system operates from a rechargeable battery.

Meteorological conditions are associated with physical activities performed in open-air settings

NASA Astrophysics Data System (ADS)

Suminski, Richard R.; Poston, Walker C.; Market, Patrick; Hyder, Melissa; Sara, Pyle A.

2008-01-01

Meteorological conditions (MC) are believed to modify physical activity. However, studies in this area are limited and none have looked at the associations between MC and physical activity in open-air settings. Therefore, we examined the relationships between MC and physical activities performed on sidewalks/streets and outdoor oval tracks. Observation techniques were used to count individuals walking to school, exercising on oval tracks and walking/jogging/biking on sidewalks/streets. Meteorological conditions were obtained from an Automated Surface Observing System located at a nearby airport for the same time periods physical activities were observed. On weekdays, fewer children were seen walking to school and more bicyclists were observed on sidewalks/streets as wind speed increased ( p < 0.05). Ambient and apparent temperatures were positively ( p < 0.05) and humidity and barometric pressure negatively ( p < 0.005) related to the number of individuals walking on the track. Meteorological conditions were not significantly associated with physical activities observed on weekends. Multiple linear regression analyses showed that apparent temperature (+), barometric pressure (-) and dew point (-) accounted for 58.0% of the variance in the number of walkers on the track. A significant proportion of the variance (>30%) in the number of joggers and the length of time they jogged was accounted for by apparent temperature (+) and dew point (-). We found that meteorological conditions are related to physical activity in open-air settings. The results embellish the context in which environmental-physical activity relationships should be interpreted and provide important information for researchers applying the observation method in open-air settings.

Aspiration lung disorders in bovines: a case report and review.

PubMed

Shakespeare, Anthony S

2012-11-01

Lung aspiration disorders in bovines are invariably diagnosed as infectious aspiration pneumonias. There is a distinct differentiation between aspiration pneumonia and aspiration pneumonitis in humans that can be applied to bovines. The nature and quantity of the aspirate can result in differing pathogeneses which can require differing therapeutic approaches. Whilst blood gases were important in detecting and prognosticating lung problems, changes in barometric pressure with altitude have to be considered when interpreting partial pressures of oxygen. Anatomical differences in the lungs of bovines can explain why this species is more prone to certain pneumonic problems. Pulmonary physiotherapy is important in treating lung disorders in humans and should be considered as an adjunct therapy in bovine respiratory conditions. A case work-up was used to highlight some of the points discussed in this article.

Transport of Carbon Tetrachloride in a Fractured Vadose Zone due to Atmospheric Pressure Fluctuations, Diffusion, and Vapor Density

NASA Astrophysics Data System (ADS)

McCray, J. E.; Downs, W.; Falta, R. W.; Housley, T.

2005-12-01

DNAPL sources of carbon tetrachloride (CT) vapors are of interest at the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering and Environmental Laboratory (INEEL). The site is underlain by thick fractured basalt that includes sedimentary interbeds, each are a few meters thick. Daily atmospheric pressure fluctuations serve as driving forces for CT vapor transport in the subsurface. Other important transport processes for vapor movement include gas-phase diffusion and density-driven transport. The objective of this research is to investigate the influence and relative importance of these processes on gaseous transport of CT. Gas pressure and vapor concentration measurements were conducted at various depths in two wells. A numerical multiphase flow model (TOUGH2), calibrated to field pressure data, is used to conduct sensitivity analyses to elucidate the importance of the different transport mechanisms. Results show that the basalt is highly permeable to vertical air flow. The pressure dampening occurs mainly in the sedimentary interbeds. Model-calibrated permeability values for the interbeds are similar to those obtained in a study by the U.S. Geological Survey for shallow sediments, and an order of magnitude higher than column-scale values obtained by previous studies conducted by INEEL scientists. The transport simulations indicate that considering the effect of barometric pressure changes is critical to simulating transport of pollutants in the vadose zone above the DNAPL source. Predicted concentrations can be orders of magnitude smaller than actual concentrations if the effect is not considered. Below the DNAPL vapor source, accounting for density and diffusion alone would yield acceptable results provided that a 20% error in concentrations are acceptable, and that simulating concentrations trends (and not actual concentrations) is the primary goal.

Surface and Tower Meteorological Instrumentation at NSA Handbook - January 2006

DOE Office of Scientific and Technical Information (OSTI.GOV)

MT Ritsche

2006-01-30

The Surface and Tower Meteorological Instrumentation at Atqasuk (METTWR2H) uses mainly conventional in situ sensors to measure wind speed, wind direction, air temperature, dew point and humidity mounted on a 10-m tower. It also obtains barometric pressure, visibility, and precipitation data from sensors at or near the base of the tower. In addition, a Chilled Mirror Hygrometer is located at 1 m for comparison purposes. Temperature and relative humidity probes are mounted at 2 m and 5 m on the tower. For more information, see the Surface and Tower Meteorological Instrumentation at Atqasuk Handbook.

A Multi-Year Dust Devil Vortex Survey Using an Automated Search of Pressure Time-Series

NASA Astrophysics Data System (ADS)

Jackson, Brian K.; Lorenz, Ralph

2014-11-01

Dust devils occur in arid climates on the Earth and ubiquitously on Mars, where they likely dominate the supply of atmospheric dust and influence climate. Martian dust devils have been studied with a combination of orbiting and landed spacecraft, while most studies of terrestrial dust devils have involved manned monitoring of field sites, which can be costly both in time and personnel. As an alternative approach, we describe a multi-year in-situ survey of terrestrial dust devils using pressure loggers deployed at El Dorado Playa in Nevada, USA, a site known for dust devil activity. Analogous to previous surveys for Martian dust devils, we conduct a post-hoc analysis of the barometric data to search for putative dust devil pressure dips using a new automated detection algorithm. We investigate the completeness and false positive rates of our new algorithm and conduct several statistically robust analyses of the resulting population of dips. We also investigate seasonal, annual, and spatial variability of the putative dust devil dips, possible correlations with precipitation, and the influence of sample size on the derived population statistics. Our results suggest that large numbers of dips (> 1,000) collected over multiple seasons are probably required for accurate assessment of the underlying dust devil population. Correlating long-term barometric time-series with other data streams (e.g., solar flux measurements from photovoltaic cells) can uniquely elucidate the natures and origins of dust devils, and accurately assessing their influence requires consideration of the full distribution of dust devil properties, rather than average values. For example, our results suggest the dust flux from the average terrestrial devil is nearly 1,000 times smaller than the (more representative) population-weighted average flux. If applicable to Martian dust devils, such corrections may help resolve purported discrepancies between the dust fluxes estimated from dust devil studies and those required to maintain the atmospheric dust concentration.

A piecewise regression approach for determining biologically relevant hydraulic thresholds for the protection of fishes at river infrastructure.

PubMed

Boys, C A; Robinson, W; Miller, B; Pflugrath, B; Baumgartner, L J; Navarro, A; Brown, R; Deng, Z

2016-05-01

A piecewise regression approach was used to objectively quantify barotrauma injury thresholds in two physoclistous species, Murray cod Maccullochella peelii and silver perch Bidyanus bidyanus, following simulated infrastructure passage in a barometric chamber. The probability of injuries such as swimbladder rupture, exophthalmia and haemorrhage, and emphysema in various organs increased as the ratio between the lowest exposure pressure and the acclimation pressure (ratio of pressure change, R(NE:A) ) reduced. The relationship was typically non-linear and piecewise regression was able to quantify thresholds in R(NE:A) that once exceeded resulted in a substantial increase in barotrauma injury. Thresholds differed among injury types and between species but by applying a multispecies precautionary principle, the maintenance of exposure pressures at river infrastructure above 70% of acclimation pressure (R(NE:A) of 0·7) should protect downstream migrating juveniles of these two physoclistous species sufficiently. These findings have important implications for determining the risk posed by current infrastructures and informing the design and operation of new ones. © 2016 The Fisheries Society of the British Isles.

Examining Changes in Radioxenon Isotope Activity Ratios during Subsurface Transport

NASA Astrophysics Data System (ADS)

Annewandter, Robert

2014-05-01

The Non-Proliferation Experiment (NPE) has demonstrated and modelled the usefulness of barometric pumping induced gas transport and subsequent soil gas sampling during On-Site inspections. Generally, gas transport has been widely studied with different numerical codes. However, gas transport of radioxenons and radioiodines in the post-detonation regime and their possible fractionation is still neglected in the open peer-reviewed literature. Atmospheric concentrations of the radioxenons Xe-135, Xe-133m, Xe-133 and Xe-131m can be used to discriminate between civilian releases (nuclear power plants or medical isotope facilities), and nuclear explosion sources. It is based on the multiple isotopic activity ratio method. Yet it is not clear whether subsurface migration of the radionuclides, with eventual release into the atmosphere, can affect the activity ratios due to fractionation. Fractionation can be caused by different mass diffusivities due to mass differences between the radionuclides. Cyclical changes in atmospheric pressure can drive subsurface gas transport. This barometric pumping phenomenon causes an oscillatoric flow in upward trending fractures or highly conductive faults which, combined with diffusion into the porous matrix, leads to a net transport of gaseous components - a so-called ratcheting effect. We use a general purpose reservoir simulator (Complex System Modelling Platform, CSMP++) which is recognized by the oil industry as leading in Discrete Fracture-Matrix (DFM) simulations. It has been applied in a range of fields such as deep geothermal systems, three-phase black oil simulations, fracture propagation in fractured, porous media, and Navier-Stokes pore-scale modelling among others. It is specifically designed to account for structurally complex geologic situation of fractured, porous media. Parabolic differential equations are solved by a continuous Galerkin finite-element method, hyperbolic differential equations by a complementary finite volume method. The parabolic and hyperbolic problem can be solved separately by operator-splitting. The resulting system of linear equations is solved by the algebraic multigrid library SAMG, developed at the Fraunhofer Institute for Algorithms and Scientific Computing, Germany. CSMP++ is developed at Montan University of Leoben, ETH Zuerich, Imperial College London and Heriot-Watt University in Edinburgh. This study examines barometric pumping-driven subsurface transport of Xe-135, Xe-133m, Xe-133, Xe-131m including I-131, I-133 and I-135 on arrival times and isotopic activity ratios. This work was funded by the CTBTO Research Award for Young Scientist and Engineers (2013).

Magnetic Ripples Observed by Low-altitude Satellites and their Relation to Micro-barometric and Ground Magnetic Variations

NASA Astrophysics Data System (ADS)

Iyemori, T.; Aoyama, T.; Nakanishi, K.; Odagi, Y.; Sanoo, Y.; Yokoyama, Y.; Yamada, A.

2017-12-01

The `magnetic ripples' are small scale magnetic fluctuations observed in upper ionosphere by low altitude satellites such as CHAMP or Swarm, and they are spatial structure of field-aligned currents along satellite orbit. They are observed almost always in mid- and low-latitudes. From their geographical and seasonal characteristics, they are supposed to be caused by the atmospheric waves which propagates from lower atmosphere to the ionosphere. Although the global distribution and its local time or seasonal variation of the amplitude of magnetic ripples, or the correlation with meteorological phenomena such as typhoons strongly suggest the cumulus convection as the main origin, we need to clarify which mode of atmospheric waves, i.e., acoustic wave or internal gravity wave, mainly contributes to the magnetic ripples and what meteorological condition correspond them. For those purposes, we analyze ground based magnetic and micro-barometric variations. We try to make quantitative estimation of the contribution from both acoustic and internal mode of gravity waves, acoustic resonance, etc. by calculating PSD (power spectral density) of pressure and ground magnetic variations. In this paper, we present their basic characteristics and discuss the relation with magnetic ripples. [Acknowledgments]: The ground observations have been supported by many people including students at our graduate school and by the collaboration with other institutions.

Measuring Low Frequency Tilts

PubMed Central

Kohl, M. L.; Levine, J.

1993-01-01

A borehole tiltmeter with a sensitivity of a few nanoradians is described. It is composed of two orthogonal horizontal pendulums with free periods of 1 s. The pendulums are insensitive to barometric pressure fluctuations, and the measured temperature coefficient is less than 30 nrad/°C. The range of the pendulums is about ±5 μ rad, and their response is linear within 1% and stable over several years. The performance of the tiltmeter in the field was evaluated using tidal data obtained from a closely spaced array of boreholes in Southern California. The long-term stability of the tiltmeter is generally better than 1 μ rad/yr. The data also indicate that instruments in boreholes at least 24 m deepare independent of surface effects. Several different capsules designed to couple the instrument to the surrounding material have been tested. In addition, an experimental method for estimating the magnitudes of local perturbation in the regional tilt field is described. PMID:28053466

Airborne detection of diffuse carbon dioxide emissions at Mammoth Mountain, California

USGS Publications Warehouse

Gerlach, T.M.; Doukas, M.P.; McGee, K.A.; Kessler, R.

1999-01-01

We report the first airborne detection of CO2 degassing from diffuse volcanic sources. Airborne measurement of diffuse CO2 degassing offers a rapid alternative for monitoring CO2 emission rates at Mammoth Mountain. CO2 concentrations, temperatures, and barometric pressures were measured at ~2,500 GPS-referenced locations during a one-hour, eleven-orbit survey of air around Mammoth Mountain at ~3 km from the summit and altitudes of 2,895-3,657 m. A volcanic CO2 anomaly 4-5 km across with CO2 levels ~1 ppm above background was revealed downwind of tree-kill areas. It contained a 1-km core with concentrations exceeding background by >3 ppm. Emission rates of ~250 t d-1 are indicated. Orographic winds may play a key role in transporting the diffusely degassed CO2 upslope to elevations where it is lofted into the regional wind system.We report the first airborne detection of CO2 degassing from diffuse volcanic sources. Airborne measurement of diffuse CO2 degassing offers a rapid alternative for monitoring CO2 emission rates at Mammoth Mountain. CO2 concentrations, temperatures, and barometric pressures were measured at approximately 2,500 GPS-referenced locations during a one-hour, eleven-orbit survey of air around Mammoth Mountain at approximately 3 km from the summit and altitudes of 2,895-3,657 m. A volcanic CO2 anomaly 4-5 km across with CO2 levels approximately 1 ppm above background was revealed downwind of tree-kill areas. It contained a 1-km core with concentrations exceeding background by >3 ppm. Emission rates of approximately 250 t d-1 are indicated. Orographic winds may play a key role in transporting the diffusely degassed CO2 upslope to elevations where it is lofted into the regional wind system.

Model-free data analysis for source separation based on Non-Negative Matrix Factorization and k-means clustering (NMFk)

NASA Astrophysics Data System (ADS)

Vesselinov, V. V.; Alexandrov, B.

2014-12-01

The identification of the physical sources causing spatial and temporal fluctuations of state variables such as river stage levels and aquifer hydraulic heads is challenging. The fluctuations can be caused by variations in natural and anthropogenic sources such as precipitation events, infiltration, groundwater pumping, barometric pressures, etc. The source identification and separation can be crucial for conceptualization of the hydrological conditions and characterization of system properties. If the original signals that cause the observed state-variable transients can be successfully "unmixed", decoupled physics models may then be applied to analyze the propagation of each signal independently. We propose a new model-free inverse analysis of transient data based on Non-negative Matrix Factorization (NMF) method for Blind Source Separation (BSS) coupled with k-means clustering algorithm, which we call NMFk. NMFk is capable of identifying a set of unique sources from a set of experimentally measured mixed signals, without any information about the sources, their transients, and the physical mechanisms and properties controlling the signal propagation through the system. A classical BSS conundrum is the so-called "cocktail-party" problem where several microphones are recording the sounds in a ballroom (music, conversations, noise, etc.). Each of the microphones is recording a mixture of the sounds. The goal of BSS is to "unmix'" and reconstruct the original sounds from the microphone records. Similarly to the "cocktail-party" problem, our model-freee analysis only requires information about state-variable transients at a number of observation points, m, where m > r, and r is the number of unknown unique sources causing the observed fluctuations. We apply the analysis on a dataset from the Los Alamos National Laboratory (LANL) site. We identify and estimate the impact and sources are barometric pressure and water-supply pumping effects. We also estimate the location of the water-supply pumping wells based on the available data. The possible applications of the NMFk algorithm are not limited to hydrology problems; NMFk can be applied to any problem where temporal system behavior is observed at multiple locations and an unknown number of physical sources are causing these fluctuations.

Automatic Barometric Updates from Ground-Based Navigational Aids

DTIC Science & Technology

1990-03-12

ro fAutomatic Barometric Updates US Department from of Transportation Ground-Based Federal Aviation Administration Navigational Aids Office of Safety...tighter vertical spacing controls , particularly for operations near Terminal Control Areas (TCAs), Airport Radar Service Areas (ARSAs), military climb and...E.F., Ruth, J.C., and Williges, B.H. (1987). Speech Controls and Displays. In Salvendy, G., E. Handbook of Human Factors/Ergonomics, New York, John

Using smartphone pressure sensors to measure vertical velocities of elevators, stairways, and drones

NASA Astrophysics Data System (ADS)

Monteiro, Martín; Martí, Arturo C.

2017-01-01

We measure the vertical velocities of elevators, pedestrians climbing stairs, and drones (flying unmanned aerial vehicles), by means of smartphone pressure sensors. The barometric pressure obtained with the smartphone is related to the altitude of the device via the hydrostatic approximation. From the altitude values, vertical velocities are derived. The approximation considered is valid in the first hundred meters of the inner layers of the atmosphere. In addition to pressure, acceleration values were also recorded using the built-in accelerometer. Numerical integration was performed, obtaining both vertical velocity and altitude. We show that data obtained using the pressure sensor is significantly less noisy than that obtained using the accelerometer. Error accumulation is also evident in the numerical integration of the acceleration values. In the proposed experiments, the pressure sensor also outperforms GPS, because this sensor does not receive satellite signals indoors and, in general, the operating frequency is considerably lower than that of the pressure sensor. In the cases in which it is possible, comparison with reference values taken from the architectural plans of buildings validates the results obtained using the pressure sensor. This proposal is ideally performed as an external or outreach activity with students to gain insight about fundamental questions in mechanics, fluids, and thermodynamics.

Acclimatization and tolerance to extreme altitude

NASA Technical Reports Server (NTRS)

West, J. B.

1993-01-01

During the last ten years, two major experiments have elucidated the factors determining acclimatization and tolerance to extreme altitude (over 7000 m). These were the American Medical Research Expedition to Everest, and the low pressure chamber simulation, Operation Everest II. Extreme hyperventilation is one of the most important responses to extreme altitude. Its chief value is that it allows the climber to maintain an alveolar PO2 which keeps the arterial PO2 above dangerously low levels. Even so, there is evidence of residual impairment of central nervous system function after ascents to extreme altitude, and maximal oxygen consumption falls precipitously above 7000 m. The term 'acclimatization' is probably not appropriate for altitudes above 8000 m, because the body steadily deteriorates at these altitudes. Tolerance to extreme altitude is critically dependent on barometric pressure, and even seasonal changes in pressure probably affect climbing performance near the summit of Mt Everest. Supplementary oxygen always improves exercise tolerance at extreme altitudes, and rescue oxygen should be available on climbing expeditions to 8000 m peaks.

Multifuctional integrated sensors (MFISES).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Homeijer, Brian D.; Roozeboom, Clifton

2015-10-01

Many emerging IoT applications require sensing of multiple physical and environmental parameters for: completeness of information, measurement validation, unexpected demands, improved performance. For example, a typical outdoor weather station measures temperature, humidity, barometric pressure, light intensity, rainfall, wind speed and direction. Existing sensor technologies do not directly address the demand for cost, size, and power reduction in multi-paramater sensing applications. Industry sensor manufacturers have developed integrated sensor systems for inertial measurements that combine accelerometers, gyroscopes, and magnetometers, but do not address environmental sensing functionality. In existing research literature, a technology gap exists between the functionality of MEMS sensors and themore » real world applications of the sensors systems.« less

Bronchopulmonary dysplasia: effect of altitude correction and role for the Neonatal Research Network Prediction Algorithm.

PubMed

Gulliver, Kristina; Yoder, Bradley A

2018-05-09

To determine the effect of altitude correction on bronchopulmonary dysplasia (BPD) rates and to assess validity of the NICHD "Neonatal BPD Outcome Estimator" for predicting BPD with and without altitude correction. Retrospective analysis included neonates born <30 weeks gestational age (GA) between 2010 and 2016. "Effective" FiO 2 requirements were determined at 36 weeks corrected GA. Altitude correction performed via ratio of barometric pressure (BP) in our unit to sea level BP. Probability of death and/or moderate-to-severe BPD was calculated using the NICHD BPD Outcome Estimator. Five hundred and sixty-one infants were included. Rate of moderate-to-severe BPD decreased from 71 to 40% following altitude correction. Receiver-operating characteristic curves indicated high predictability of BPD Outcome Estimator for altitude-corrected moderate-to-severe BPD diagnosis. Correction for altitude reduced moderate-to-severe BPD rate by almost 50%, to a rate consistent with recent published values. NICHD BPD Outcome Estimator is a valid tool for predicting the risk of moderate-to-severe BPD following altitude correction.

Vertical and horizontal seismometric observations of tides

NASA Astrophysics Data System (ADS)

Lambotte, S.; Rivera, L.; Hinderer, J.

2006-01-01

Tidal signals have been largely studied with gravimeters, strainmeters and tiltmeters, but can also be retrieved from digital records of the output of long-period seismometers, such as STS-1, particularly if they are properly isolated. Horizontal components are often noisier than the vertical ones, due to sensitivity to tilt at long periods. Hence, horizontal components are often disturbed by local effects such as topography, geology and cavity effects, which imply a strain-tilt coupling. We use series of data (duration larger than 1 month) from several permanent broadband seismological stations to examine these disturbances. We search a minimal set of observable signals (tilts, horizontal and vertical displacements, strains, gravity) necessary to reconstruct the seismological record. Such analysis gives a set of coefficients (per component for each studied station), which are stable over years and then can be used systematically to correct data from these disturbances without needing heavy numerical computation. A special attention is devoted to ocean loading for stations close to oceans (e.g. Matsushiro station in Japon (MAJO)), and to pressure correction when barometric data are available. Interesting observations are made for vertical seismometric components; in particular, we found a pressure admittance between pressure and data 10 times larger than for gravimeters for periods larger than 1 day, while this admittance reaches the usual value of -3.5 nm/s 2/mbar for periods below 3 h. This observation may be due to instrumental noise, but the exact mechanism is not yet understood.

Effects of weather and heliophysical conditions on emergency ambulance calls for elevated arterial blood pressure.

PubMed

Vencloviene, Jone; Babarskiene, Ruta M; Dobozinskas, Paulius; Sakalyte, Gintare; Lopatiene, Kristina; Mikelionis, Nerijus

2015-02-27

We hypothesized that weather and space weather conditions were associated with the exacerbation of essential hypertension. The study was conducted during 2009-2010 in the city of Kaunas, Lithuania. We analyzed 13,475 cards from emergency ambulance calls (EACs), in which the conditions for the emergency calls were made coded I.10-I.15. The Kaunas Weather Station provided daily records of air temperature (T), wind speed (WS), relative humidity, and barometric pressure (BP). We evaluated the associations between daily weather variables and daily number of EACs by applying a multivariate Poisson regression. Unfavorable heliophysical conditions (two days after the active-stormy geomagnetic field or the days with solar WS>600 km/s) increased the daily number of elevated arterial blood pressure (EABP) by 12% (RR=1.12; 95% confidence interval (CI) 1.04-1.21); and WS≥3.5 knots during days of T<1.5 °C and T≥12.5 °C by 8% (RR=1.08; CI 1.04-1.12). An increase of T by 10 °C and an elevation of BP two days after by 10 hPa were associated with a decrease in RR by 3%. An additional effect of T was detected during days of T≥17.5 °C only in females. Women and patients with grade III arterial hypertension at the time of the ambulance call were more sensitive to weather conditions. These results may help in the understanding of the population's sensitivity to different weather conditions.

June 13, 2013 U.S. East Coast Meteotsunami: Comparing a Numerical Model With Observations

NASA Astrophysics Data System (ADS)

Wang, D.; Becker, N. C.; Weinstein, S.; Whitmore, P.; Knight, W.; Kim, Y.; Bouchard, R. H.; Grissom, K.

2013-12-01

On June 13, 2013, a tsunami struck the U.S. East Coast and caused several reported injuries. This tsunami occurred after a derecho moved offshore from North America into the Atlantic Ocean. The presence of this storm, the lack of a seismic source, and the fact that tsunami arrival times at tide stations and deep ocean-bottom pressure sensors cannot be attributed to a 'point-source' suggest this tsunami was caused by atmospheric forces, i.e., a meteotsunami. In this study we attempt to reproduce the observed phenomenon using a numerical model with idealized atmospheric pressure forcing resembling the propagation of the observed barometric anomaly. The numerical model was able to capture some observed features of the tsunami at some tide stations, including the time-lag between the time of pressure jump and the time of tsunami arrival. The model also captures the response at a deep ocean-bottom pressure gauge (DART 44402), including the primary wave and the reflected wave. There are two components of the oceanic response to the propagating pressure anomaly, inverted barometer response and dynamic response. We find that the dynamic response over the deep ocean to be much smaller than the inverted barometer response. The time lag between the pressure jump and tsunami arrival at tide stations is due to the dynamic response: waves generated and/or reflected at the shelf-break propagate shoreward and amplify due to the shoaling effect. The evolution of the derecho over the deep ocean (propagation direction and intensity) is not well defined, however, because of the lack of data so the forcing used for this study is somewhat speculative. Better definition of the pressure anomaly through increased observation or high resolution atmospheric models would improve meteotsunami forecast capabilities.

Evaluating Cumulative Ascent:. Mountain Biking Meets Mandelbrot

NASA Astrophysics Data System (ADS)

Rapaport, D. C.

The problem of determining total distance ascended during a mountain bike trip is addressed. Altitude measurements are obtained from GPS receivers utilizing both GPS-based and barometric altitude data, with data averaging used to reduce fluctuations. The estimation process is sensitive to the degree of averaging, and is related to the well-known question of determining coastline length. Barometric-based measurements prove more reliable, due to their insensitivity to GPS altitude fluctuations.

How low can they go when going with the flow? Tolerance of egg and larval fishes to rapid decompression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boys, Craig A.; Robinson, Wayne; Miller, Brett

Egg and larval fish that drift downstream are likely to encounter river infrastructure and consequently rapid decompression, which may result in significant injury. In juvenile fish, pressure-related injury (or barotrauma) occurs when pressures fall sufficiently below the pressure at which the fish has acclimated. Because eggs and larvae are less-developed and more fragile than juveniles, there is a presumption that they may be at least as, if not more, susceptible to barotrauma injury, but studies to date report inconsistent results and none have considered the relationship between pressure change and barotrauma over a sufficiently broad range of pressure changes tomore » enable detrimental levels to be properly determined. To address this, we exposed eggs and larvae of three physoclistic species to rapid decompression in a barometric chamber over a broad range of discrete pressure changes. Eggs, but not larvae, were unaffected by all levels of decompression tested. At exposure pressures below ~40 kPa, or ~40% of atmospheric pressure, swim bladder deflation occurred in all species and internal haemorrhage was observed in one species. None of these injuries killed the fish within 24 hours, but subsequent mortality cannot be excluded. Consequently, if larval drift is expected, it seems prudent to maintain exposure pressures at river infrastructure at 40% or more of the pressure to which a drifting larvae has acclimated.« less

A transmission-line model of back-cavity dynamics for in-plane pressure-differential microphones.

PubMed

Kim, Donghwan; Kuntzman, Michael L; Hall, Neal A

2014-11-01

Pressure-differential microphones inspired by the hearing mechanism of a special parasitoid fly have been described previously. The designs employ a beam structure that rotates about two pivots over an enclosed back volume. The back volume is only partially enclosed due to open slits around the perimeter of the beam. The open slits enable incoming sound waves to affect the pressure profile in the microphone's back volume. The goal of this work is to study the net moment applied to pressure-differential microphones by an incoming sound wave, which in-turn requires modeling the acoustic pressure distribution within the back volume. A lumped-element distributed transmission-line model of the back volume is introduced for this purpose. It is discovered that the net applied moment follows a low-pass filter behavior such that, at frequencies below a corner frequency depending on geometrical parameters of the design, the applied moment is unaffected by the open slits. This is in contrast to the high-pass filter behavior introduced by barometric pressure vents in conventional omnidirectional microphones. The model accurately predicts observed curvature in the frequency response of a prototype pressure-differential microphone 2 mm × 1 mm × 0.5 mm in size and employing piezoelectric readout.

A piecewise regression approach for determining biologically relevant hydraulic thresholds for the protection of fish at river infrastructure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boys, Craig A.; Robinson, Wayne; Miller, Brett

2016-05-13

Barotrauma injury can occur when fish are exposed to rapid decompression during downstream passage through river infrastructure. A piecewise regression approach was used to objectively quantify barotrauma injury thresholds in two physoclistous species (Murray cod Maccullochella peelii and silver perch Bidyanus bidyanus) following simulated infrastructure passage in barometric chambers. The probability of injuries such as swim bladder rupture; exophthalmia; and haemorrhage and emphysema in various organs increased as the ratio between the lowest exposure pressure and the acclimation pressure (ratio of pressure change RPCE/A) fell. The relationship was typically non-linear and piecewise regression was able to quantify thresholds in RPCE/Amore » that once exceeded resulted in a substantial increase in barotrauma injury. Thresholds differed among injury types and between species but by applying a multi-species precautionary principle, the maintenance of exposure pressures at river infrastructure above 70% of acclimation pressure (RPCE/A of 0.7) should sufficiently protect downstream migrating juveniles of these two physoclistous species. These findings have important implications for determining the risk posed by current infrastructures and informing the design and operation of new ones.« less

Parylene-on-oil packaging for long-term implantable pressure sensors.

PubMed

Shapero, Aubrey M; Liu, Yang; Tai, Yu-Chong

2016-08-01

This paper reports and analyzes the feasibility study of a parylene-on-oil encapsulation packaging method of pressure sensors targeted for long-term implantation. Commercial barometric digital-output pressure sensors are enclosed in silicone oil and then encapsulated in situ with parylene-C or -D (PA-C, PA-D) chemical vapor deposition. Experimentally, sensors encapsulated with 30,000 cSt silicone oil and 27 μm PA-D show good performance for 6 weeks in 77 °C saline with >99 % of original sensitivity, corresponding to an extrapolated lifetime of around 21 months in 37 °C saline. This work shows that, with proper designs, such a packaging method can preserve the original pressure sensor sensitivity without offset, validated throughout accelerated lifetime tests. In experiments, wires on the prototypes are used for external electronics but it is found that they contributed to early failures, which would be absent in real wireless versions, indicating a potential for even longer lifetimes. Finally, a verified model is presented to predict the pressure sensor sensitivity of parylene-on-oil packaging with and without the presence of a bubble in the oil.

Strain transients in the Gulf of Corinth (Greece)

NASA Astrophysics Data System (ADS)

Canitano, Alexandre; Bernard, Pascal; Linde, Alan; Sacks, Selwyn; Boudin, Frederick

2010-05-01

The Gulf of Corinth (Greece) is one of the most seismic regions in Europe, producing some earthquakes of magnitude greater than 5.8 in the last 35 years, 1 to 1.5 cm/yr of north-south extension, and frequent seismic swarms. This structure is a 110 km long, N110E oriented graben bounded by systems of very recent normal faults. This zone thus provides an ideal site for investigating in situ the physics of earthquake sources and for developing efficient seismic hazard reduction procedures. The Corinth Rift Laboratory (CRL) project is concentrated in the western part of the rift, around the city of Aigion, where instrumental seismicity and strain rate is highest. The CRL Network is made up about fifteen seismic stations as well as tiltmeters, strainmeters or GPS in order to study the local seismicity, and to observe and model the short and long term mechanics of the normal fault system. The instrumental seismicity in the Aigion zone clearly shows a strong concentration of small earthquakes between 5 and 10 km. In order to study slow transient deformation, two borehole strainmeters have been installed in the Gulf (Trizonia, Monasteraki). The strainmeter installed in the Trizonia island is continuously recording the horizontal strain at 150m depth with a resolution better than 10-9. The dominant signal is the earth and sea tidal effects (few 10-7 strain), this one is modulated by the mechanical effects of the free oscillations of the Gulf with periods between 8 and 40 min. The barometric pressure fluctuations acts in combination with the mean sea level variation at longer periods and both effects are not independant. The comparison between the strain data and the two forcing signals (sea-level, barometric pressure) shows clearly a non zero phase delay of the sea-level. The analysis of time correlations between the signals in differents frequency range exhibits that the sea level delay and the strainmeter/sea-level coupling coefficient are increasing with period (about 1/10 of a period for 10-40 hrs period range). This analysis allows us to estimate a transfert function for each forcing signal but the physical interpretation of the sea-level function is difficult. As the strainmeter is at 150m depth, below the shoreline, a sea water percolation on land would increase the effect of sea level fluctuation, and be more efficient at longer periods. This interpretation and the study of the mechanical effects on strainmeter allow us to accurate the sea level admittance and to remove the water effect from the strain data. This residual signals are studied in order to find slow transient signatures, especially during the reported seismic swarms.

Barometric Tides from ECMWF Operational Analyses

NASA Technical Reports Server (NTRS)

Ray, R. D.; Ponte, R. M.

2003-01-01

The solar diurnal and semidiurnal tidal oscillations in surface pressure are extracted from the the operational analysis product of the European Centre for Medium Range Weather Forecasting (ECMWF). For the semidiurnal tide this involves a special temporal interpolation, following Van den Dool and colleagues. The resulting tides are compared with a ground truth tide dataset, a compilation of well-determined tide estimates deduced from long time series of station barometer measurements. These comparisons show that the ECMWF tides are significantly more accurate than the tides deduced from two other widely available reanalysis products. Spectral analysis of ECMWF pressure series shows that the tides consist of sharp central peaks with modulating sidelines at integer multiples of 1 cycle/year, superimposed on a broad cusp of stochastic energy. The integrated energy in the cusp dominates that of the sidelines. This complicates development of a simple model that can characterize the full temporal variability of the tides.

Eating and rumination behaviour of Scottish Highland cattle on pasture and in loose housing during the winter.

PubMed

Braun, U; Storni, E; Hässig, M; Nuss, K

2014-09-01

This study examined eating and rumination behaviour in 13 Scottish Highland cattle for 13 days on a winter pasture and then for 13 days in a loose housing barn during winter. The cows were fed hay ad libitum and each was fitted with a pressure-sensitive transducer integrated into the noseband of the halter. The endpoints for each cow at both locations were calculated per day and included eating and rumination times, number of chewing cycles related to eating and rumination, number of regurgitated cuds and number of chewing cycles per cud. Air temperature, wind speed, relative humidity, barometric pressure and precipitation were recorded. Pastured cows had significantly longer eating and rumination times, more chewing cycles related to eating and rumination, more regurgitated cuds and more chewing cycles per cud than housed cows. Meteorological conditions were very similar at both locations.

Climate-induced variations of geyser periodicity in Yellowstone National Park, USA

USGS Publications Warehouse

Hurwitz, S.; Kumar, A.; Taylor, R.; Heasler, H.

2008-01-01

The geysers of Yellowstone National Park, United States, attract millions of visitors each year, and their eruption dynamics have been the subject of extensive research for more than a century. Although many of the fundamental aspects associated with the dynamics of geyser eruptions have been elucidated, the relationship between external forcing (Earth tides, barometric pressure, and precipitation) and geyser eruption intervals (GEIs) remains a matter of ongoing debate. We present new instrumental GEI data and demonstrate, through detailed time-series analysis, that geysers respond to both long-term precipitation trends and to the seasonal hydrologic cycle. Responsiveness to long-term trends is reflected by a negative correlation between the annual averages of GEIs and stream flow in the Madison River. This response is probably associated with long-term pressure changes in the underlying hydrothermal reservoir. We relate seasonal GEI lengthening to snowmelt recharge. ?? 2008 The Geological Society of America.

Observation of the Earth Liquid Core Resonance by Extensometers

NASA Astrophysics Data System (ADS)

Bán, Dóra; Mentes, Gyula; Kis, Márta; Koppán, András

2018-05-01

We performed Earth tidal measurements by quartz tube extensometers of the same type at several observatories (Budapest, Pécs, Sopronbánfalva in Hungary and Vyhne in Slovakia). In this paper, the first attempts to reveal the effect of the Free Core Nutation (FCN) from strain measurements are described. The effect of the FCN on the P1, K1, Ψ1 and Φ1 tidal waves were studied on the basis of tidal results obtained in four observatories. Effectiveness of the correction of tidal data for temperature, barometric pressure and ocean load was also investigated. The obtained K1/O1 ratios are close to the theoretical values with exception of the Pécs station. We found a discrepancy between the observed and theoretical P1/O1 values for all stations with exception of the Budapest station. It was found that the difference between the measured and theoretical Ψ1/O1 and Φ1/O1 ratios was very large independently of correction of the strain data. These discrepancies need further investigations. According to our results, fluid core resonance effects can also be detected by our quartz tube extensometers but correction of strain data for local effects is necessary.

The functional dependence of canopy conductance on water vapor pressure deficit revisited

NASA Astrophysics Data System (ADS)

Fuchs, Marcel; Stanghellini, Cecilia

2018-03-01

Current research seeking to relate between ambient water vapor deficit (D) and foliage conductance (g F ) derives a canopy conductance (g W ) from measured transpiration by inverting the coupled transpiration model to yield g W = m - n ln(D) where m and n are fitting parameters. In contrast, this paper demonstrates that the relation between coupled g W and D is g W = AP/D + B, where P is the barometric pressure, A is the radiative term, and B is the convective term coefficient of the Penman-Monteith equation. A and B are functions of g F and of meteorological parameters but are mathematically independent of D. Keeping A and B constant implies constancy of g F . With these premises, the derived g W is a hyperbolic function of D resembling the logarithmic expression, in contradiction with the pre-set constancy of g F . Calculations with random inputs that ensure independence between g F and D reproduce published experimental scatter plots that display a dependence between g W and D in contradiction with the premises. For this reason, the dependence of g W on D is a computational artifact unrelated to any real effect of ambient humidity on stomatal aperture and closure. Data collected in a maize field confirm the inadequacy of the logarithmic function to quantify the relation between canopy conductance and vapor pressure deficit.

The effect of weather on mood, productivity, and frequency of emotional crisis in a temperate continental climate

NASA Astrophysics Data System (ADS)

Barnston, A. G.

1988-06-01

A group of 62 mostly university student subjects kept structured diaries of their feelings and their productivity for six weeks in Illinois in early autumn. During the same period, daily frequency of telephone calls to a crisis intervention service in the same community was monitored, and complete daily weather data for the vicinity were provided by a local meteorological research facility. Major findings are as follows. The weather appears to influence mood and productivity, but only to a smallextent compared with the aggregate of all other controlling factors. Males show a relatively stronger effect than females. Psychologically troubled people generally appear to be more affected by weather than university students. The students and the crisis intervention service clients with “mild” problems tend to be stressed more when the weather is unstable, cloudy, warm and humid, and least stressed during sunny, dry, cool weather with rising barometric pressure. The crisis service clients with “severe” problems react oppositely to these two weather types. The meaning of these and other results and the strengths and weaknesses of this study's design are discussed.

Dynamic Vertical Mapping with Crowdsourced Smartphone Sensor Data

PubMed Central

Moslehi Rad, Omid Reza; Prehofer, Christian; Hugentobler, Urs

2018-01-01

In this paper, we present our novel approach for the crowdsourced dynamic vertical mapping of buildings. For achieving this, we use the barometric sensor of smartphones to estimate altitude differences and the moment of the outdoor to indoor transition to extract reference pressure. We have identified the outdoor–indoor transition (OITransition) via the fusion of four different sensors. Our approach has been evaluated extensively over a period of 6 months in different humidity, temperature, and cloud-coverage situations, as well as over different hours of the day, and it is found that it can always predict the correct number of floors, while it can approximate the altitude with an average error of 0.5 m. PMID:29415472

Monitoring storm tide and flooding from Hurricane Sandy along the Atlantic coast of the United States, October 2012

USGS Publications Warehouse

McCallum, Brian E.; Wicklein, Shaun M.; Reiser, Robert G.; Busciolano, Ronald J.; Morrison, Jonathan; Verdi, Richard J.; Painter, Jaime A.; Frantz, Eric R.; Gotvald, Anthony J.

2013-01-01

The U.S. Geological Survey (USGS) deployed a temporary monitoring network of water-level and barometric pressure sensors at 224 locations along the Atlantic coast from Virginia to Maine to continuously record the timing, areal extent, and magnitude of hurricane storm tide and coastal flooding generated by Hurricane Sandy. These records were greatly supplemented by an extensive post-flood high-water mark (HWM) flagging and surveying campaign from November to December 2012 involving more than 950 HWMs. Both efforts were undertaken as part of a coordinated federal emergency response as outlined by the Stafford Act under a directed mission assignment by the Federal Emergency Management Agency (FEMA).

Meteorological Automatic Weather Station (MAWS) Instrument Handbook

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holdridge, Donna J; Kyrouac, Jenni A

The Meteorological Automatic Weather Station (MAWS) is a surface meteorological station, manufactured by Vaisala, Inc., dedicated to the balloon-borne sounding system (BBSS), providing surface measurements of the thermodynamic state of the atmosphere and the wind speed and direction for each radiosonde profile. These data are automatically provided to the BBSS during the launch procedure and included in the radiosonde profile as the surface measurements of record for the sounding. The MAWS core set of measurements is: Barometric Pressure (hPa), Temperature (°C), Relative Humidity (%), Arithmetic-Averaged Wind Speed (m/s), and Vector-Averaged Wind Direction (deg). The sensors that collect the core variablesmore » are mounted at the standard heights defined for each variable.« less

R4D Program: Climatological observations in the Philip Smith Mountains of the North Slope, Alaska: Climatology report series No. 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelley, J.J.

1985-10-01

Climatological data from an automatic weather station (MR1) located at the Alyeska Pipeline Service Company Material Site 117 (MS-117) are presented in this report. Data are listed for half-hour averages daily. Hourly data are also listed for a redundant system (Aanderaa). The data report covers the period 7 June 1985 to 26 August 1985. Observations in this report include wind speed and direction, temperature from the ground to 10 m, relative humidity, precipitation and barometric pressure. Descriptions of the instrumentation and estimates of relativity are included. Various analyses of the data are presented in the appendices. (ACR)

Friction of Aviation Engines

NASA Technical Reports Server (NTRS)

Sparrow, S W; Thorne, M A

1928-01-01

The first portion of this report discusses measurements of friction made in the altitude laboratory of the Bureau of Standards between 1920 and 1926 under research authorization of the National Advisory Committee for Aeronautics. These are discussed with reference to the influence of speed, barometric pressure, jacket-water temperature, and throttle opening upon the friction of aviation engines. The second section of the report deals with measurements of the friction of a group of pistons differing from each other in a single respect, such as length, clearance, area of thrust face, location of thrust face, etc. Results obtained with each type of piston are discussed and attention is directed particularly to the fact that the friction chargeable to piston rings depends upon piston design as well as upon ring design. This is attributed to the effect of the rings upon the thickness and distribution of the oil film which in turn affects the friction of the piston to an extent which depends upon its design.

Increased 2,3-diphosphoglycerate during normocapnic hypobaric hypoxia.

PubMed

Cymerman, A; Maher, J T; Cruz, J C; Reeves, J T; Denniston, J C; Grover, R F

1976-10-01

The effect of 96 h of exposure to hypobaric hypoxia with and without 3.8% CO2 supplementation was studied in two groups of subjects. Five subjects (CO2) were exposed to 440-465 mm Hg barometric pressure (4000-4400 m), and 4 subjects (no-CO2) were exposed to 455-492 mm Hg (3500-1400 m) in order to produce similar levels of resting end-tidal PO2. After 24 h, 2,3-DPG levels of both groups significantly increased and remained elevated. The CO2 group had higher levels than the non-CO2 group after 48 and 72 h. Concurrent measurements of P50 showed similar changes over the same time course. Mean corpuscular hemoglobin concentrations remained normal for 48 h and then decreased in both groups, the CO2 group showing the larger decrease. We conclude that altitude exposure may produce an increase in 2,3-DPG without the presence of respiratory alkalosis previously thought necessary.

Seasonal and geothermal production variations in concentrations of He and CO2 in soil gases, Roosevelt Hot Springs Known Geothermal Resource Area, Utah, U.S.A.

USGS Publications Warehouse

Hinkle, M.E.

1991-01-01

To increase understanding of natural variations in soil gas concentrations, CO2, He, O2 and N2 were measured in soil gases collected regularly for several months from four sites at the Roosevelt Hot Springs Known Geothermal Resource Area, Utah. Soil temperature, air temperature, per cent relative humidity, barometric pressure and amounts of rain and snowfall were also monitored to determine the effect of meteorological parameters on concentrations of the measured gases. Considerable seasonal variation existed in concentrations of CO2 and He. The parameters that most affected the soil-gas concentrations were soil and air temperatures. Moisture from rain and snow probably affected the soil-gas concentrations also. However, annual variations in meteorological parameters did not appear to affect measurements of anomalous concentrations in samples collected within a time period of a few days. Production from some of the geothermal wells probably affected the soil-gas concentrations. ?? 1990.

Aircraft cabin air quality: an overview [correction of overvier].

PubMed

Rayman, R B

2001-03-01

In recent years, there have been increasing complaints from cockpit crew, cabin crew, and passengers that the cabin air quality of commercial aircraft is deficient. A myriad of complaints including headache, fatigue, fever, and respiratory difficulties among many others have been registered, particularly by flight attendants on long haul routes. There is also much concern today regarding the transmission of contagious disease inflight, particularly tuberculosis. The unanswered question is whether these complaints are really due to poor cabin air quality or to other factors inherent inflight such as lowered barometric pressure, hypoxia, low humidity, circadian dysynchrony, work/rest cycles, vibration etc. This paper will review some aspects relevant to cabin air quality such as carbon dioxide (CO2), carbon monoxide (CO), ozone (O3), particulates, and microorganisms as well as the cabin ventilation system to discern if there is a possible cause and effect of illness contracted inflight. The paper will conclude with recommendations on how the issue of cabin air quality may be resolved.

Effect of climatological factors on respiratory syncytial virus epidemics

PubMed Central

NOYOLA, D. E.; MANDEVILLE, P. B.

2008-01-01

SUMMARY Respiratory syncytial virus (RSV) presents as yearly epidemics in temperate climates. We analysed the association of atmospheric conditions to RSV epidemics in San Luis Potosí, S.L.P., Mexico. The weekly number of RSV detections between October 2002 and May 2006 were correlated to ambient temperature, barometric pressure, relative humidity, vapour tension, dew point, precipitation, and hours of light using time-series and regression analyses. Of the variation in RSV cases, 49·8% was explained by the study variables. Of the explained variation in RSV cases, 32·5% was explained by the study week and 17·3% was explained by meteorological variables (average daily temperature, maximum daily temperature, temperature at 08:00 hours, and relative humidity at 08:00 hours). We concluded that atmospheric conditions, particularly temperature, partly explain the year to year variability in RSV activity. Identification of additional factors that affect RSV seasonality may help develop a model to predict the onset of RSV epidemics. PMID:18177520

Are there evidences of altitudinal effects of air temperature trends in the European Alps 1820-2013?

NASA Astrophysics Data System (ADS)

Schoener, W.; Auer, I.; Chimani, B.; Garnekind, M.; Haslinger, K.

2013-12-01

We use the HISTALP data set (www.zamg.ac.at/histalp) in order to assess the elevation dependency of air temperature trends within the European Alps. The evidence of altitudinal effects of the climate warming (with higher sensitivity of high mountain regions to warming) is a key statement, or at least key hypothesis, in many studies. The high relevance of such statement resp. hypothesis is obvious if one consider the impacts resulting from such fact, such as snow- and glacier melting and related effects for mountain hydrology. The HISTALP data set stands out with respect to its series lengths and its high level of homogenisation. Interestingly, the HISTALP temperature data show no clear altitudinal dependency of warming or cooling trends within the period 1820-2013. Additionally, a rather homogenous temporal trend could be observed within the entire Greater Alpine Region (GAR). Because HISTALP include also air pressure and vapour pressure series, we could compare our measured air temperatures with mean-column air temperatures, computed by the barometric formula, which were derived from the independently measured air pressure data (using vapour pressure to account for the atmospheric water content) at low resp. high elevations. Computed mean column temperatures are in good agreement with observed temperatures, indicating generally homogenous temporal temperature trend behaviour at different elevations. Our finding contradicts several results from climate modelling attempts and also other studies investigating Alpine temperature trends. We conclude that, whereas modelling results are still limited in the assessment of altitudinal effect of temperature trends from missing atmospheric processes captured by the models, the difference of the trend behaviour compared to other analyses of instrumental air temperatures comes from the seasonal base taken as the basis for trend estimation. It appears that opposite trend in spring and autumn for the period 1980-2000, respectively, levels each other out for the annual temperature trend.

Effects of Weather and Heliophysical Conditions on Emergency Ambulance Calls for Elevated Arterial Blood Pressure

PubMed Central

Vencloviene, Jone; Babarskiene, Ruta M.; Dobozinskas, Paulius; Sakalyte, Gintare; Lopatiene, Kristina; Mikelionis, Nerijus

2015-01-01

We hypothesized that weather and space weather conditions were associated with the exacerbation of essential hypertension. The study was conducted during 2009–2010 in the city of Kaunas, Lithuania. We analyzed 13,475 cards from emergency ambulance calls (EACs), in which the conditions for the emergency calls were made coded I.10–I.15. The Kaunas Weather Station provided daily records of air temperature (T), wind speed (WS), relative humidity, and barometric pressure (BP). We evaluated the associations between daily weather variables and daily number of EACs by applying a multivariate Poisson regression. Unfavorable heliophysical conditions (two days after the active-stormy geomagnetic field or the days with solar WS > 600 km/s) increased the daily number of elevated arterial blood pressure (EABP) by 12% (RR = 1.12; 95% confidence interval (CI) 1.04–1.21); and WS ≥ 3.5 knots during days of T < 1.5 °C and T ≥ 12.5 °C by 8% (RR = 1.08; CI 1.04–1.12). An increase of T by 10 °C and an elevation of BP two days after by 10 hPa were associated with a decrease in RR by 3%. An additional effect of T was detected during days of T ≥ 17.5 °C only in females. Women and patients with grade III arterial hypertension at the time of the ambulance call were more sensitive to weather conditions. These results may help in the understanding of the population’s sensitivity to different weather conditions. PMID:25734792

An internally consistent pressure calibration of geobarometers applicable to the Earth’s upper mantle using in situ XRD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beyer, Christopher; Rosenthal, Anja; Myhill, Robert

We have performed an experimental cross calibration of a suite of mineral equilibria within mantle rock bulk compositions that are commonly used in geobarometry to determine the equilibration depths of upper mantle assemblages. Multiple barometers were compared simultaneously in experimental runs, where the pressure was determined using in-situ measurements of the unit cell volumes of MgO, NaCl, Re and h-BN between 3.6 and 10.4 GPa, and 1250 and 1500 °C. The experiments were performed in a large volume press (LVPs) in combination with synchrotron X-ray diffraction. Noble metal capsules drilled with multiple sample chambers were loaded with a range ofmore » bulk compositions representative of peridotite, eclogite and pyroxenite lithologies. By this approach, we simultaneously calibrated the geobarometers applicable to different mantle lithologies under identical and well determined pressure and temperature conditions. We identified discrepancies between the calculated and experimental pressures for which we propose simple linear or constant correction factors to some of the previously published barometric equations. As a result, we establish internally-consistent cross-calibrations for a number of garnet-orthopyroxene, garnet-clinopyroxene, Ca-Tschermaks-in-clinopyroxene and majorite geobarometers.« less

Documentation of a spreadsheet for time-series analysis and drawdown estimation

USGS Publications Warehouse

Halford, Keith J.

2006-01-01

Drawdowns during aquifer tests can be obscured by barometric pressure changes, earth tides, regional pumping, and recharge events in the water-level record. These stresses can create water-level fluctuations that should be removed from observed water levels prior to estimating drawdowns. Simple models have been developed for estimating unpumped water levels during aquifer tests that are referred to as synthetic water levels. These models sum multiple time series such as barometric pressure, tidal potential, and background water levels to simulate non-pumping water levels. The amplitude and phase of each time series are adjusted so that synthetic water levels match measured water levels during periods unaffected by an aquifer test. Differences between synthetic and measured water levels are minimized with a sum-of-squares objective function. Root-mean-square errors during fitting and prediction periods were compared multiple times at four geographically diverse sites. Prediction error equaled fitting error when fitting periods were greater than or equal to four times prediction periods. The proposed drawdown estimation approach has been implemented in a spreadsheet application. Measured time series are independent so that collection frequencies can differ and sampling times can be asynchronous. Time series can be viewed selectively and magnified easily. Fitting and prediction periods can be defined graphically or entered directly. Synthetic water levels for each observation well are created with earth tides, measured time series, moving averages of time series, and differences between measured and moving averages of time series. Selected series and fitting parameters for synthetic water levels are stored and drawdowns are estimated for prediction periods. Drawdowns can be viewed independently and adjusted visually if an anomaly skews initial drawdowns away from 0. The number of observations in a drawdown time series can be reduced by averaging across user-defined periods. Raw or reduced drawdown estimates can be copied from the spreadsheet application or written to tab-delimited ASCII files.

Tube bundle system studies at Signal Peak Energy Bull Mountains #1 Mine

PubMed Central

Zipf, R.K.; Ochsner, R.; Krog, R.; Marchewka, W.; Valente, M.; Jensen, R.

2015-01-01

A tube bundle system (TBS) is a mechanical system for continuously drawing gas samples through tubes from multiple monitoring points located in an underground coal mine for analysis and display on the surface. The U.S. National Institute for Occupational Safety and Health (NIOSH), in collaboration with Signal Peak Energy (SPE), LLC, Bull Mountains No. 1 Mine, operated a TBS during mining of two bleederless, longwall panels. This paper describes the gas analysis data and its interpretation. As verified by the TBS, coal at the SPE mine tends to oxidize slowly. It was known that a reservoir of low-oxygen concentration atmosphere developed about 610 m (2,000 ft) behind the longwall face. A bleederless ventilation system facilitates formation of an inert atmosphere in this longwall gob and decreases the likelihood of spontaneous combustion. Connections of the mine atmosphere to the surface through subsidence cracks could allow airflow into the longwall gob, revive coal oxidation and increase spontaneous combustion risk. The atmospheric composition of the sealed areas was homogeneous, except in the immediate vicinity of suspected ingassing points. The TBS verified that gases within the partially sealed, bleederless longwall gob expanded into the longwall tailgate area when barometric pressure decreased. The concentration of carbon dioxide in the back return airflow at the longwall tailgate was observed to increase by a factor of three and possibly up to 10 times the typical background concentration of 0.5 to 1.0%, depending on the size of the longwall gob and the magnitude of barometric pressure decrease. TBS have the inherent disadvantage of slow response time due to travel time of the gas samples and sequential gas analyses. A TBS or similar continuous monitoring system could be beneficial in detecting and providing warning of potentially hazardous gas concentrations, if the slow response time of the system is always understood. PMID:26306075

Tube bundle system studies at Signal Peak Energy Bull Mountains #1 Mine.

PubMed

Zipf, R K; Ochsner, R; Krog, R; Marchewka, W; Valente, M; Jensen, R

2014-03-01

A tube bundle system (TBS) is a mechanical system for continuously drawing gas samples through tubes from multiple monitoring points located in an underground coal mine for analysis and display on the surface. The U.S. National Institute for Occupational Safety and Health (NIOSH), in collaboration with Signal Peak Energy (SPE), LLC, Bull Mountains No. 1 Mine, operated a TBS during mining of two bleederless, longwall panels. This paper describes the gas analysis data and its interpretation. As verified by the TBS, coal at the SPE mine tends to oxidize slowly. It was known that a reservoir of low-oxygen concentration atmosphere developed about 610 m (2,000 ft) behind the longwall face. A bleederless ventilation system facilitates formation of an inert atmosphere in this longwall gob and decreases the likelihood of spontaneous combustion. Connections of the mine atmosphere to the surface through subsidence cracks could allow airflow into the longwall gob, revive coal oxidation and increase spontaneous combustion risk. The atmospheric composition of the sealed areas was homogeneous, except in the immediate vicinity of suspected ingassing points. The TBS verified that gases within the partially sealed, bleederless longwall gob expanded into the longwall tailgate area when barometric pressure decreased. The concentration of carbon dioxide in the back return airflow at the longwall tailgate was observed to increase by a factor of three and possibly up to 10 times the typical background concentration of 0.5 to 1.0%, depending on the size of the longwall gob and the magnitude of barometric pressure decrease. TBS have the inherent disadvantage of slow response time due to travel time of the gas samples and sequential gas analyses. A TBS or similar continuous monitoring system could be beneficial in detecting and providing warning of potentially hazardous gas concentrations, if the slow response time of the system is always understood.

How low can they go when going with the flow? Tolerance of egg and larval fishes to rapid decompression

PubMed Central

Boys, Craig A.; Robinson, Wayne; Miller, Brett; Pflugrath, Brett; Baumgartner, Lee J.; Navarro, Anna; Brown, Richard; Deng, Zhiqun

2016-01-01

ABSTRACT Egg and larval fish that drift downstream are likely to encounter river infrastructure and consequently rapid decompression, which may result in significant injury. Pressure-related injury (or barotrauma) has been shown in juvenile fishes when pressure falls sufficiently below that at which the fish has acclimated. There is a presumption that eggs and larvae may be at least as, if not more, susceptible to barotrauma injury because they are far less-developed and more fragile than juveniles, but studies to date report inconsistent results and none have considered the relationship between pressure change and barotrauma over a sufficiently broad range of pressure changes to enable tolerances to be properly determined. To address this, we exposed eggs and larvae of three physoclistic species to rapid decompression in a barometric chamber over a broad range of discrete pressure changes. Eggs, but not larvae, were unaffected by all levels of decompression tested. At exposure pressures below ∼40 kPa, or ∼40% of surface pressure, swim bladder deflation occurred in all species and internal haemorrhage was observed in one species. None of these injuries killed the fish within 24 h, but subsequent mortality cannot be excluded. Consequently, if larval drift is expected where river infrastructure is present, adopting design or operational features which maintain exposure pressures at 40% or more of the pressure to which drifting larvae are acclimated may afford greater protection for resident fishes. PMID:27230649

Effects of some air pollutants and meteorological conditions on airborne algae and protozoa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, P.E.

1973-10-01

The effects of meteorological conditions and specific air pollutants on the viability of airborne algae and protozoa were investigated. Such investigations will be of interest to medical researchers because these organisms are the source of many allergies. The three air pollutants that were continuously measured and recorded were sulfur, hydrocarbons, and particulate matter. During the experiment, 25 different species of algae and 19 species of protozoa were collected from the atmosphere and cultured at the Westinghouse environmental Station Laboratory in Raleigh, North Carolina. The algae and protozoa were collected over a one-year period (Jan-Dec 1971) by using a sequential samplermore » that moved air through a membrane filter at the rate of 15 ft/sup 3//hr. Every two hours a new filter was sequentially moved in to replace the old one. The results indicated a relationship between wind speed, wind direction, temperature, dewpoint, particulate matter, barometric pressure, and rainfall to the percent frequency of positive culture tubes and number of cell/ft/sup 3/ of air. Further studies are necessary to determine the interrelationships between the physical and chemical character of various air masses and their effect on the survival of algae and protozoa.« less

In-situ fluid-pressure measurements for earthquake prediction: An example from a deep well at Hi Vista, California

USGS Publications Warehouse

Healy, J.H.; Urban, T.C.

1985-01-01

Short-term earthquake prediction requires sensitive instruments for measuring the small anomalous changes in stress and strain that precede earthquakes. Instruments installed at or near the surface have proven too noisy for measuring anomalies of the size expected to occur, and it is now recognized that even to have the possibility of a reliable earthquake-prediction system will require instruments installed in drill holes at depths sufficient to reduce the background noise to a level below that of the expected premonitory signals. We are conducting experiments to determine the maximum signal-to-noise improvement that can be obtained in drill holes. In a 592 m well in the Mojave Desert near Hi Vista, California, we measured water-level changes with amplitudes greater than 10 cm, induced by earth tides. By removing the effects of barometric pressure and the stress related to earth tides, we have achieved a sensitivity to volumetric strain rates of 10-9 to 10-10 per day. Further improvement may be possible, and it appears that a successful earthquake-prediction capability may be achieved with an array of instruments installed in drill holes at depths of about 1 km, assuming that the premonitory strain signals are, in fact, present. ?? 1985 Birkha??user Verlag.

Occurrence and attempted mitigation of carbon dioxide in a home constructed on reclaimed coal-mine spoil, Pike County, Indiana

USGS Publications Warehouse

Robinson, Bret A.

2010-01-01

In recent years carbon dioxide intrusion has become recognized as a potentially serious health threat where homes are constructed on or near reclaimed surface coal mines. When carbon dioxide invades the living space of a home, it can collect near the floor, displace the oxygen there, and produce an oxygen-deficient environment. In this investigation, several lines of inquiry were pursued to determine the environmental factors that most influence carbon dioxide intrusion at a Pike County, Ind., home where this phenomenon is known to occur. It was found that carbon dioxide intrusion events at the home are most closely tied to rapid drops in barometric pressure and rainfall. Other researchers have shown that windy conditions and periods of cold weather also can contribute to soil-gas intrusion to structures. From this, a conceptual model was developed to illustrate the influence of these four meteorological conditions. Additionally, three mitigation methods-block-wall depressurization, block-wall and sub-slab depressurization, and block-wall and sub-slab pressurization-were applied successively to the study-site home, and environmental data were collected to evaluate the effectiveness of each mitigation method. In each case, it was found that these methods did not ensure a safe environment when meteorological conditions were favorable for carbon dioxide intrusion.

Different kernel functions due to rainfall response from borehole strainmeter in Taiwan

NASA Astrophysics Data System (ADS)

Yen Chen, Chih; Hu, Jyr Ching; LIu, Chi Ching

2014-05-01

In order to realize reasons inducing earthquakes, project of monitoring of the fault activity using 3-component Gladwin Tensor Strainmeter (GTSM) has been initiated since 2003 in Taiwan, which is one of the most active seismic regions in the world. Observed strain contains several different effects within including barometric, tidal, groundwater, precipitation, tectonics, seismic and other irregular noise. After removing the response of tides and air pressure on strain, we still can find some anomalies highly related to the rainfall in short time in days. The strain response induced by rainfall can be separated into two parts as observation in groundwater, slow response and quick response, respectively. Quick response reflects the strain responding to the load of falling water drops on the ground surface. A kernel function shows the continual response induced by unit precipitation water in time domain. We split the quick response from data removing tidal and barometric response, and then calculate the kernel function by use of deconvolution method. More, an average kernel function was calculated to reduce the noise level. There are five of the sites installed by CGS Taiwan were selected to calculate kernel functions for individual sites. The results show there may be different on rainfall response in different environmental settings. In the case of stations site on gentle terrain, kernel function for each site shows the similar trend, it rises quickly to maximum in 1 to 2 hrs, and then goes down near to zero gently in period of 2-3 days. But in the case of sites settled side by the rivers, there will be 2nd peak of function when collected water in the catchment flows along by the sites related to the hydrograph of creeks. More, landslides will occur in some sites in hazard of landslide with more rainfall stored on, just like DARB in ChiaYi. The curve of kernel function will be controlled by landslides and debris flows.

Hydromechanical coupling in geologic processes

USGS Publications Warehouse

Neuzil, C.E.

2003-01-01

Earth's porous crust and the fluids within it are intimately linked through their mechanical effects on each other. This paper presents an overview of such "hydromechanical" coupling and examines current understanding of its role in geologic processes. An outline of the theory of hydromechanics and rheological models for geologic deformation is included to place various analytical approaches in proper context and to provide an introduction to this broad topic for nonspecialists. Effects of hydromechanical coupling are ubiquitous in geology, and can be local and short-lived or regional and very long-lived. Phenomena such as deposition and erosion, tectonism, seismicity, earth tides, and barometric loading produce strains that tend to alter fluid pressure. Resulting pressure perturbations can be dramatic, and many so-called "anomalous" pressures appear to have been created in this manner. The effects of fluid pressure on crustal mechanics are also profound. Geologic media deform and fail largely in response to effective stress, or total stress minus fluid pressure. As a result, fluid pressures control compaction, decompaction, and other types of deformation, as well as jointing, shear failure, and shear slippage, including events that generate earthquakes. By controlling deformation and failure, fluid pressures also regulate states of stress in the upper crust. Advances in the last 80 years, including theories of consolidation, transient groundwater flow, and poroelasticity, have been synthesized into a reasonably complete conceptual framework for understanding and describing hydromechanical coupling. Full coupling in two or three dimensions is described using force balance equations for deformation coupled with a mass conservation equation for fluid flow. Fully coupled analyses allow hypothesis testing and conceptual model development. However, rigorous application of full coupling is often difficult because (1) the rheological behavior of geologic media is complex and poorly understood and (2) the architecture, mechanical properties and boundary conditions, and deformation history of most geologic systems are not well known. Much of what is known about hydromechanical processes in geologic systems is derived from simpler analyses that ignore certain aspects of solid-fluid coupling. The simplifications introduce error, but more complete analyses usually are not warranted. Hydromechanical analyses should thus be interpreted judiciously, with an appreciation for their limitations. Innovative approaches to hydromechanical modeling and obtaining critical data may circumvent some current limitations and provide answers to remaining questions about crustal processes and fluid behavior in the crust.

Experimental Research Into High Barometric Oxygen Prevention of Guinea Pig Hearing Loss,

DTIC Science & Technology

1992-08-28

PREVENTION OF GUINEA PIG HEARING LOSS by Yin Jiacai, Sun Fang ren, et al. DTIC MLECTE •<• EP 2 9 1992 Approved for public release, Distribution unlimited...PREVENTION OF GUINEA PIG HEARING LOSS By: Yin Jiacai, Sun Fang ren, et al. English pages: 9 Source: Chung-Hua I Shueh Tsa Chih, Vol. 65, Nr. 11, Nov.eember...Distributionf._DL~~~t .•b • / or __ Dlist szeccat .lef ’ ~1 EXPERIMENTAL RESEARCH INTO HIGH BAROMETRIC OXYGEN PREVENTION OF GUINEA PIG HEARING LOSS BY: Yin

Simulation of gas bubbles in hypobaric decompressions: roles of O2, CO2, and H2O.

PubMed

Van Liew, H D; Burkard, M E

1995-01-01

To gain insight into the special features of bubbles that may form in aviators and astronauts, we simulated the growth and decay of bubbles in two hypobaric decompressions and a hyperbaric one, all with the same tissue ratio (TR), where TR is defined as tissue PN2 before decompression divided by barometric pressure after. We used an equation system which is solved by numerical methods and accounts for simultaneous diffusion of any number of gases as well as other major determinants of bubble growth and absorption. We also considered two extremes of the number of bubbles which form per unit of tissue. A) Because physiological mechanisms keep the partial pressures of the "metabolic" gases (O2, CO2, and H2O) nearly constant over a range of hypobaric pressures, their fractions in bubbles are inversely proportional to pressure and their large volumes at low pressure add to bubble size. B) In addition, the large fractions facilitate the entry of N2 into bubbles, and when bubble density is low, enhance an autocatalytic feedback on bubble growth due to increasing surface area. C) The TR is not closely related to bubble size; that is when two different decompressions have the same TR, metabolic gases cause bubbles to grow larger at lower hypobaric pressures. We conclude that the constancy of partial pressures of metabolic gases, unimportant in hyperbaric decompressions, affects bubble size in hypobaric decompressions in inverse relation to the exposure pressure.

Climatological observations in the Philip Smith Mountains of the North Slope, Alaska: Climatology report series No. 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelley, J.J.; Foster, D.

1986-10-01

Climatological data from an automatic weather station (Aanderaa) located at the Alyeska Pipeline Service Company Material Site 117 (MS-117) are presented in this report. Data are listed for hourly averages daily. The data report covers the period 1 August 1985 to 31 May 1986. Observations in this report include wind speed and direction, temperature and barometric pressure. Descriptions of the instrumentation and estimates of reliability are included in the test. Various analyses of the data are presented in the appendices. A summary of the wind and temperature regime is presented through displays of cumulative frequencies of hourly temperatures and windmore » speeds for the 12-month period, June 1985 to May 1986.« less

Connected car: Engines diagnostic via Internet of Things (IoT)

NASA Astrophysics Data System (ADS)

Hamid, A. F. A.; Rahman, M. T. A.; Khan, S. F.; Adom, A. H.; Rahim, M. A.; Rahim, N. A.; Ismail, M. H. N.; Norizan, A.

2017-10-01

This paper is about an experiment for performing engines diagnostic using wireless sensing Internet of Thing (IoT). The study is to overcome problem of current standard On Board Diagnosis (OBD-II) data acquisition method that only can be perform in offline or wired method. From this paper it show a method to determined how the data from engines can be collected, make the data can be easily understand by human and sending data over the wireless internet connection via platform of IOT. This study is separate into three stages that is CAN-bus data collection, CAN data conversion and send data to cloud storage. Every stage is experimented with a two different method and consist five data parameter that is Revolution per Minute (RPM), Manifold Air Pressure (MAP), load-fuel, barometric pressure and engine temperature. The experiment use Arduino Uno as microcontroller, CAN-bus converter and ESP8266 wifi board as transfer medium for data to internet.

Pressure Variations in Metamorphic Rocks: Implications for the Interpretation of Petrographic Observations

NASA Astrophysics Data System (ADS)

Tajčmanová, Lucie

2014-05-01

Metamorphic petrologists and structural geologists, using direct measurements, bring the only direct observational constrains for validating geodynamic models. Therefore, petrological and structural geological observations are essential for the quality and reproducibility of geodynamic reconstructions and models. One of the important assumptions for geodynamic reconstructions arises from the pressure and temperature estimates in the petrology analysis. Pressure is commonly converted to depth through the equation for lithostatic pressure and so the original position of the rock sample within the Earth's interior can be constrained. The current assumption that the studied sample corresponds to uniform pressure may not be correct, and if so, it has serious implications. Increasing evidence from analytical data shows that pressure is not constant even on a grain scale, posing new challenges because, if ignored, it leads to an incorrect use of petrology data in constraining geodynamic models. Well known examples of the preservation of coesite and diamond in a host mineral like garnet show that high pressure inclusions are preserved during decompression. Tajčmanová et al. (2014) has shown that grain-scale pressure variations can develop and that these pressure variations allow compositional zoning in minerals preserved over geological time scales. A new unconventional barometric method based on equilibrium under pressure variations has been developed . Such pressure variations are also connected with differences in fluid pressure in open systems and can be thus observed at all scales. Tajčmanová L., Podladchikov Y., Powell R., Moulas E., Vrijmoed J. and Connolly J. (2014). Grain scale pressure variations and chemical equilibrium in high-grade metamorphic rocks.Journal of Metamorphic Geology, doi:10.1111/jmg.12066 This work was supported by ERC starting grant 335577 to Lucie Tajcmanova

Comparison of Bacillus atrophaeus spore viability following exposure to detonation of C4 and to deflagration of halogen-containing thermites

NASA Astrophysics Data System (ADS)

Tringe, J. W.; Létant, S. E.; Dugan, L. C.; Levie, H. W.; Kuhl, A. L.; Murphy, G. A.; Alves, S. W.; Vandersall, K. S.; Pantoya, M. L.

2013-12-01

Energetic materials are being considered for the neutralization of spore-forming bacteria. In this study, the neutralization effects of a monomolecular explosive were compared to the effects of halogen-containing thermites. Bacillus atrophaeus spores were exposed to the post-detonation environment of a 100 g charge of the military explosive C-4 at a range of 50 cm. These tests were performed in the thermodynamically closed environment of a 506-l barometric calorimeter. Associated temperatures were calculated using a thermodynamic model informed by calculations with the Cheetah thermochemical code. Temperatures in the range of 2300-2800 K were calculated to persist for nearly the full 4 ms pressure observation time. After the detonation event, spores were characterized using optical microscopy and the number of viable spores was assessed. Results showed live spore survival rates in the range of 0.01%-1%. For the thermite tests, a similar, smaller-scale configuration was employed that examined the spore neutralization effects of two thermites: aluminum with iodine pentoxide and aluminum with potassium chlorate. Only the former mixture resulted in spore neutralization. These results indicate that the detonation environment produced by an explosive with no chemical biocides may provide effective spore neutralization similar to a deflagrating thermite containing iodine.

Associations of Meteorology with Adverse Pregnancy Outcomes: A Systematic Review of Preeclampsia, Preterm Birth and Birth Weight

PubMed Central

Beltran, Alyssa J.; Wu, Jun; Laurent, Olivier

2013-01-01

The relationships between meteorology and pregnancy outcomes are not well known. This article reviews available evidence on the relationships between seasonality or meteorology and three major pregnancy outcomes: the hypertensive disorders of pregnancy (including preeclampsia, eclampsia and gestational hypertension), gestational length and birth weight. In total 35, 28 and 27 studies were identified for each of these outcomes. The risks of preeclampsia appear higher for women with conception during the warmest months, and delivery in the coldest months of the year. Delivery in the coldest months is also associated with a higher eclampsia risk. Patterns of decreased gestational lengths have been observed for births in winter, as well as summer months. Most analytical studies also report decreases in gestational lengths associated with heat. Birth weights are lower for deliveries occurring in winter and in summer months. Only a limited number of studies have investigated the effects of barometric pressure on gestational length or the effects of temperature and sunshine exposure on birth weight, but these questions appear worth investigating further. Available results should encourage further etiological research aiming at enhancing our understanding of the relationships between meteorology and adverse pregnancy outcomes, ideally via harmonized multicentric studies. PMID:24362545

Associations of meteorology with adverse pregnancy outcomes: a systematic review of preeclampsia, preterm birth and birth weight.

PubMed

Beltran, Alyssa J; Wu, Jun; Laurent, Olivier

2013-12-20

The relationships between meteorology and pregnancy outcomes are not well known. This article reviews available evidence on the relationships between seasonality or meteorology and three major pregnancy outcomes: the hypertensive disorders of pregnancy (including preeclampsia, eclampsia and gestational hypertension), gestational length and birth weight. In total 35, 28 and 27 studies were identified for each of these outcomes. The risks of preeclampsia appear higher for women with conception during the warmest months, and delivery in the coldest months of the year. Delivery in the coldest months is also associated with a higher eclampsia risk. Patterns of decreased gestational lengths have been observed for births in winter, as well as summer months. Most analytical studies also report decreases in gestational lengths associated with heat. Birth weights are lower for deliveries occurring in winter and in summer months. Only a limited number of studies have investigated the effects of barometric pressure on gestational length or the effects of temperature and sunshine exposure on birth weight, but these questions appear worth investigating further. Available results should encourage further etiological research aiming at enhancing our understanding of the relationships between meteorology and adverse pregnancy outcomes, ideally via harmonized multicentric studies.

Correlation between the season, temperature and atmospheric pressure with incidence and pathogenesis of acute appendicitis.

PubMed

Karanikolić, Aleksandar; Karanikolić, Vesna; Djordjević, Lidija; Pešić, Ivan

2016-01-01

There is very little literature data on the correlation between the seasons, temperature and atmospheric pressure, and pathogenesis of acute appendicitis (AA). The aim of this research is to investigate the association between the seasons, changes in atmospheric temperature and pressure, and patients’ age and severity of the clinical form of AA in the city of Niš This study included 395 patients diagnosed with AA, who, during the two-year period, from July 1st 2011 to June 30th 2013, were hospitalized and operated on at the Department of General Surgery, Clinical Center in Niš, Serbia. The increased average daily values of barometric pressure by 1 millibar on the day when the event took place was associated (p < 0.05) with the decrease of total risk of the occurrence of appendicitis by 2.2% (0.2–4.1%). In all observed patients, each increase of the mean daily temperature by 1°C three days before the event took place (Lag 3) was associated (p < 0.05) with the increase of total risk of the occurrence of appendicitis by 1.3% (0.1–2.5%). According to the results of this research, we can conclude that patients’ sex, age and severity of the clinical form of AA are not in connection with the seasons, while there are certain connections between appendicitis occurrence and atmospheric temperature and pressure.

Seasonal Sea-Level Variations in San Francisco Bay in Response to Atmospheric Forcing, 1980

USGS Publications Warehouse

Wang, Jingyuan; Cheng, R.T.; Smith, P.C.

1997-01-01

The seasonal response of sea level in San Francisco Bay (SFB) to atmospheric forcing during 1980 is investigated. The relations between sea-level data from the Northern Reach, Central Bay and South Bay, and forcing by local wind stresses, sea level pressure (SLP), runoff and the large scale sea level pressure field are examined in detail. The analyses show that the sea-level elevations and slopes respond to the along-shore wind stress T(V) at most times of the year, and to the cross-shore wind stress T(N) during two transition periods in spring and autumn. River runoff raises the sea-level elevation during winter. It is shown that winter precipitation in the SFB area is mainly attributed to the atmospheric circulation associated with the Alcutian Low, which transports the warm, moist air into the Bay area. A multiple linear regression model is employed to estimate the independent contributions of barometric pressure and wind stress to adjusted sea level. These calculations have a simple dynamical interpretation which confirms the importance of along-shore wind to both sea level and north-south slope within the Bay.

Meteorological influence on the occurrence of gastric dilatation-volvulus in military working dogs in Texas.

PubMed

Moore, George E; Levine, Michael; Anderson, Johnna D; Trapp, Robert J

2008-01-01

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 and/or atmospheric pressure and the occurrence of GDV in the population of high-risk working dogs in Texas. The odds of a day being a GDV day, given certain temperature and atmospheric pressure conditions for that day or the day before, was estimated using logistic regression models. There were 57 days in which GDV(s) occurred, representing 2.60% of the days in the 6-year study period. The months of November, December, and January collectively accounted for almost half (47%) of all cases. Disease risk was negatively associated with daily maximum temperature. An increased risk of GDV was weakly associated with the occurrence of large hourly drops in temperature that day and of higher minimum barometric pressure that day and the day before GDV occurrence, but extreme changes were not predictive of the disease.

Meteorological influence on the occurrence of gastric dilatation-volvulus in military working dogs in Texas

NASA Astrophysics Data System (ADS)

Moore, George E.; Levine, Michael; Anderson, Johnna D.; Trapp, Robert J.

2008-01-01

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 and/or atmospheric pressure and the occurrence of GDV in the population of high-risk working dogs in Texas. The odds of a day being a GDV day, given certain temperature and atmospheric pressure conditions for that day or the day before, was estimated using logistic regression models. There were 57 days in which GDV(s) occurred, representing 2.60% of the days in the 6-year study period. The months of November, December, and January collectively accounted for almost half (47%) of all cases. Disease risk was negatively associated with daily maximum temperature. An increased risk of GDV was weakly associated with the occurrence of large hourly drops in temperature that day and of higher minimum barometric pressure that day and the day before GDV occurrence, but extreme changes were not predictive of the disease.

Residual delay maps unveil global patterns of atmospheric nonlinearity and produce improved local forecasts

PubMed Central

Sugihara, George; Casdagli, Martin; Habjan, Edward; Hess, Dale; Dixon, Paul; Holland, Greg

1999-01-01

We use residual-delay maps of observational field data for barometric pressure to demonstrate the structure of latitudinal gradients in nonlinearity in the atmosphere. Nonlinearity is weak and largely lacking in tropical and subtropical sites and increases rapidly into the temperate regions where the time series also appear to be much noisier. The degree of nonlinearity closely follows the meridional variation of midlatitude storm track frequency. We extract the specific functional form of this nonlinearity, a V shape in the lagged residuals that appears to be a basic feature of midlatitude synoptic weather systems associated with frontal passages. We present evidence that this form arises from the relative time scales of high-pressure versus low-pressure events. Finally, we show that this nonlinear feature is weaker in a well regarded numerical forecast model (European Centre for Medium-Range Forecasts) because small-scale temporal and spatial variation is smoothed out in the grided inputs. This is significant, in that it allows us to demonstrate how application of statistical corrections based on the residual-delay map may provide marked increases in local forecast accuracy, especially for severe weather systems. PMID:10588685

Tracking performance with two breathing oxygen concentrations after high altitude rapid decompression

NASA Technical Reports Server (NTRS)

Nesthus, Thomas E.; Schiflett, Samuel G.; Oakley, Carolyn J.

1992-01-01

Current military aircraft Liquid Oxygen (LOX) systems supply 99.5 pct. gaseous Aviator's Breathing Oxygen (ABO) to aircrew. Newer Molecular Sieve Oxygen Generation Systems (MSOGS) supply breathing gas concentration of 93 to 95 pct. O2. The margin is compared of hypoxia protection afforded by ABO and MSOGS breathing gas after a 5 psi differential rapid decompression (RD) in a hypobaric research chamber. The barometric pressures equivalent to the altitudes of 46000, 52000, 56000, and 60000 ft were achieved from respective base altitudes in 1 to 1.5 s decompressions. During each exposure, subjects remained at the simulated peak altitude breathing either 100 or 94 pct. O2 with positive pressure for 60 s, followed by a rapid descent to 40000 ft. Subjects used the Tactical Life Support System (TLSS) for high altitude protection. Subcritical tracking task performance on the Performance Evaluation Device (PED) provided psychomotor test measures. Overall tracking task performance results showed no differences between the MSOGS breathing O2 concentration of 94 pct. and ABO. Significance RMS error differences were found between the ground level and base altitude trials compared to peak altitude trials. The high positive breathing pressures occurring at the peak altitudes explained the differences.

Diving at altitude: from definition to practice.

PubMed

Egi, S Murat; Pieri, Massimo; Marroni, Alessandro

2014-01-01

Diving above sea level has different motivations for recreational, military, commercial and scientific activities. Despite the apparently wide practice of inland diving, there are three major discrepancies about diving at altitude: threshold elevation that requires changes in sea level procedures; upper altitude limit of the applicability of these modifications; and independent validation of altitude adaptation methods of decompression algorithms. The first problem is solved by converting the normal fluctuation in barometric pressure to an altitude equivalent. Based on the barometric variations recorded from a meteorological center, it is possible to suggest 600 meters as a threshold for classifying a dive as an "altitude" dive. The second problem is solved by proposing the threshold altitude of aviation (2,400 meters) to classify "high" altitude dives. The DAN (Divers Alert Network) Europe diving database (DB) is analyzed to solve the third problem. The database consists of 65,050 dives collected from different dive computers. A total of 1,467 dives were found to be classified as altitude dives. However, by checking the elevation according to the logged geographical coordinates, 1,284 dives were disqualified because the altitude setting had been used as a conservative setting by the dive computer despite the fact that the dive was made at sea level. Furthermore, according to the description put forward in this manuscript, 72 dives were disqualified because the surface level elevation is lower than 600 meters. The number of field data (111 dives) is still very low to use for the validation of any particular method of altitude adaptation concerning decompression algorithms.

Recognition of microclimate zones through radon mapping, Lechuguilla Cave, Carlsbad Caverns National Park, New Mexico

USGS Publications Warehouse

Cunningham, K.I.; LaRock, E.J.

1991-01-01

Radon concentrations range from <185 to 3,515 Bq m-3 throughout Lechuguilla Cave, Carlsbad Caverns National Park, New Mexico. Concentrations in the entrance passages and areas immediately adjacent to these passages are controlled by outside air temperature and barometric pressure, similar to other Type 2 caves. Most of the cave is developed in three geographic branches beneath the entrance passages; these areas maintain Rn levels independent of surface effects, an indication that Rn levels in deep, complex caves or mines cannot be simply estimated by outside atmospheric parameters. These deeper, more isolated areas are subject to convective ventilation driven by temperature differences along the 477-m vertical extent of the cave. Radon concentrations are used to delineate six microclimate zones (air circulation cells) throughout the cave in conjunction with observed airflow data. Suspected surface connections contribute fresh air to remote cave areas demonstrated by anomalous Rn lows surrounded by higher values, the presence of mammalian skeletal remains, CO2 concentrations and temperatures lower than the cave mean, and associated surficial karst features.

Body and organ weights of rats exposed to carbon monoxide at high altitude

DOE Office of Scientific and Technical Information (OSTI.GOV)

McGrath, J.J.

1988-01-01

Male, laboratory rats were exposed for 6 wk in steel barometric chambers to (1) 100 ppm CO, (2) 15,000 ft simulated high altitude (SHA), and (3) CO at SHA. Altitude was simulated by a system of gate valves and a vacuum pump, and measured by an altimeter. CO, from high-pressure cylinders, was introduced into the air supplying each chamber through a mass flow controller and measured by a nondispersive infrared (NDIR) analyzer. Although SHA had no affect on left ventricle plus septum (LV + S), adrenal, spleen, or kidney weights, SHA decreased body weights, and increased hematocrit ratios, as wellmore » as right ventricle (RV), total heart (HT), and pituitary weights. CO had no affect on body weights, RV, HT, adrenal, spleen, or kidney weights, but CO increased hematocrit ratios and LV + S weights. There was no significant interaction between SHA and CO on any parameter except kidney weight. These results indicate that, in general, the effects produced by 15,000 ft SHA are not intensified by exposure to 100 ppm CO.« less

Response of Water Levels in Devils Hole, Death Valley National Park, Nevada, to Atmospheric Loading, Earth Tides, and Earthquakes

NASA Astrophysics Data System (ADS)

Cutillo, P. A.; Ge, S.

2004-12-01

Devils Hole, home to the endangered Devils Hole pupfish (Cyprinodon diabolis) in Death Valley National Park, Nevada, is one of about 30 springs and the largest collapse depression in the Ash Meadows area. The small pool leads to an extensive subterranean cavern within the regional Paleozoic carbonate-rock aquifer. Previous work has established that the pool level fluctuates in response to changes in barometric pressure, Earth tides and earthquakes. Analyses of these fluctuations indicate that the formation is a sensitive indicator of crustal strain, and provide important information regarding the material properties of the surrounding aquifer. Over ten years of hourly water-level measurements were analyzed for the effects of atmospheric loading and Earth tides. The short-term water-level fluctuations caused by these effects were found to be on the order of millimeters to centimeters, indicating relatively low matrix compressibility. Accordingly, the Devils Hole water-level record shows strong responses to the June 28, 1992 Landers/Little Skull Mountain earthquake sequence and to the October 16, 1999 Hector Mine earthquake. A dislocation model was used to calculate volumetric strain for each earthquake. The sensitivity of Devils Hole to strain induced by the solid Earth tide was used to constrain the modeling. Water-level decreases observed following the 1992 and 1999 earthquakes were found to be consistent with areas of crustal expansion predicted by the dislocation model. The magnitude of the water-level changes was also found to be proportional to the predicted coseismic volumetric strain. Post-seismic pore-pressure diffusion, governed by the hydraulic diffusivity of the aquifer, was simulated with a numerical model using the coseismic change in pore pressure as an initial condition. Results of the numerical model indicate that factors such as fault-plane geometry and aquifer heterogeneity may play an important role in controlling pore pressure diffusion in the Devils Hole area.

Efficient fluorescence "turn-on" sensing of dissolved oxygen by electrochemical switching.

PubMed

Shin, Ik-Soo; Hirsch, Thomas; Ehrl, Benno; Jang, Dong-Hak; Wolfbeis, Otto S; Hong, Jong-In

2012-11-06

We report on a novel method for sensing oxygen that is based on the use of a perylene diimide dye (1) which is electrochemically reduced to its nonfluorescent dianion form (1(2-)). In the presence of oxygen, the dianion is oxidized to its initial form via an electron-transfer reaction with oxygen upon which fluorescence is recovered. As a result, the fluorescence intensity of the dianion solution increases upon the addition of oxygen gas. Results demonstrate that high sensitivity is obtained, and the emission intensity shows a linear correlation with oxygen content (0.0-4.0% v/v) at ambient barometric pressure. In addition, using electrochemical reduction, oxygen determination becomes regenerative, and no significant degradation is observed over several turnovers. The limit of detection is 0.4% oxygen in argon gas.

AsMA Medical Guidelines for Air Travel: stresses of flight.

PubMed

Thibeault, Claude; Evans, Anthony D

2015-05-01

Medical Guidelines for Airline Travel provide information that enables healthcare providers to properly advise patients who plan to travel by air. Modern commercial aircraft are very safe and, in most cases, reasonably comfortable. However, all flights, short or long haul, impose stresses on passengers. Preflight stresses include airport commotion on the ground such as carrying baggage, walking long distances, getting to the gate on time, and being delayed. In-flight stresses include acceleration, vibration (including turbulence), noise, lowered barometric pressure, variations of temperature and humidity, and fatigue among others. Healthy passengers normally tolerate these stresses quite well; however, there is the potential for passengers to become ill during or after the flight due to these stresses, especially for those with pre-existing medical conditions and reduced physiological reserves.

Seismicity and strain transients in the Gulf of Corinth (Greece)

NASA Astrophysics Data System (ADS)

Canitano, A.; Bernard, P.; Linde, A. T.; Sacks, S. I.; Boudin, F.

2009-12-01

The Gulf of Corinth (Greece) is one of the most seismic regions in Europe, producing some earthquakes of magnitude greater than 5.8 in the last 35 years, 1 to 1.5 cm/yr of north-south extension, and frequent seismic swarms. This structure is a 110 km long, N110°E oriented graben bounded by systems of very recent normal faults. This zone thus provides an ideal site for investigating in situ the physics of earthquake sources and for developing efficient seismic hazard reduction procedures. The Corinth Rift Laboratory (CRL) project is concentrated in the western part of the rift, around the city of Aigion, where instrumental seismicity and strain rate is highest. The CRL Network is made up about fifteen seismic stations as well as tiltmeters, strainmeters or GPS in order to study the local seismicity, and to observe and model the short and long term mechanics of the normal fault system. The instrumental seismicity in the Aigion zone clearly shows a strong concentration of small earthquakes between 5 and 10 km. In order to study slow transient deformation, two borehole strainmeters have been installed in the Gulf (Trizonia, Monasteraki). The strainmeter installed in the Trizonia island is continuously recording the horizontal strain at 150m depth with a resolution better than 10-9. The dominant signal is the earth and sea tidal effects (few 10-7 strain), this one is modulated by the mechanical effects of the free oscillations of the Gulf with periods between 8 and 40 min. The barometric pressure fluctuations acts in combination with the mean sea level variation at longer periods and both effects are not independant. The comparison between the strain data and the two forcing signals (sea-level, barometric pressure) shows clearly a non zero phase delay of the sea-level. The analysis of time correlations between the signals in differents frequency range exhibits that the sea level delay and the strainmeter/sea-level coupling coefficient are increasing with period (about 1/10 of a period for 10-40 hrs period range). This analysis allows us to estimate a transfert function for each forcing signal but the physical interpretation of the sea-level function is still unclear. As the strainmeter is at 150m depth, below the shoreline, a sea water percolation on land would increase the effect of sea level fluctuation, and be more efficient at longer periods. This interpretation allow us to study accurately this external perturbations and to remove them from the strain signal. The residual signal is 8 times smaller than the original strain signal for 10mn-1hr period (RMS=0,27.10-9 strain and no sea-level signal delay) and 4 times for 30-40hr (RMS=0,63.10-9 strain). This residual signals are studied in order to find slow transient signatures, especially during the reported seismic swarms.

On the importance of high-frequency air-temperature fluctuations for spectroscopic corrections of open-path carbon dioxide flux measurements

NASA Astrophysics Data System (ADS)

Bogoev, Ivan; Helbig, Manuel; Sonnentag, Oliver

2015-04-01

A growing number of studies report systematic differences in CO2 flux estimates obtained with the two main types of gas analyzers: compared to eddy-covariance systems based on closed-path (CP) gas analyzers, systems with open-path (OP) gas analyzers systematically overestimate CO2 uptake during daytime periods with high positive sensible heat fluxes, while patterns for differences in nighttime CO2 exchange are less obvious. These biases have been shown to correlate with the sign and the magnitude of the sensible heat flux and to introduce large uncertainties when calculating annual CO2 budgets. In general, CP and OP gas analyzers commonly used to measure the CO2 density in the atmosphere operate on the principle of infrared light absorption approximated by Beer-Lambert's law. Non-dispersive interference-based optical filter elements are used to select spectral bands with strong attenuation of light transmission, characteristic to the gas of interest. The intensity of the light passing through the optical sensing path depends primarily on the amount of absorber gas in the measurement volume. Besides the density of the gas, barometric pressure and air temperature are additional factors affecting the strength and the half-width of the absorption lines. These so-called spectroscopic effects are accounted for by measuring barometric pressure and air temperature in the sensing path and scaling the light-intensity measurements before applying the calibration equation. This approach works well for CP gas analyzers with an intake tube that acts as a low-pass filter on fast air-temperature fluctuations. Low-frequency response temperature sensors in the measurement cell are therefore sufficient to account for spectroscopic temperature effects. In contrast, OP gas analyzers are exposed to high-frequency air-temperature fluctuations associated with the atmospheric surface-layer turbulent heat exchange. If not corrected adequately, these fast air-temperature variations can cause systematic errors in the CO2 density measurements. Under conditions of high positive or negative sensible heat flux, air-temperature fluctuations are correlated with fluctuations of the vertical wind component and can lead to significant biases in the CO2 flux estimates. This study demonstrates that sonically derived fast-response air temperature in the optical sensing path of an OP gas analyzer can replace the slow-response measurements from the temperature sensor as a scaling parameter in the calibration model to correct for these air temperature-induced spectroscopic effects. Our approach is evaluated by comparison between different OP and CP gas analyzer-based eddy-covariance systems in ecosystems with low CO2 uptake under a range of sensible heat flux regimes and varying meteorological parameters. We show that ignoring high-frequency spectroscopic effects can lead to false interpretations of net ecosystem CO2 exchange for specific site and environmental conditions.

Micro-Pressure Sensors for Future Mars Missions

NASA Technical Reports Server (NTRS)

Catling, David C.

1996-01-01

The joint research interchange effort was directed at the following principal areas: u further development of NASA-Ames' Mars Micro-meteorology mission concept as a viable NASA space mission especially with regard to the science and instrument specifications u interaction with the flight team from NASA's New Millennium 'Deep-Space 2' (DS-2) mission with regard to selection and design of micro-pressure sensors for Mars u further development of micro-pressure sensors suitable for Mars The research work undertaken in the course of the Joint Research Interchange should be placed in the context of an ongoing planetary exploration objective to characterize the climate system on Mars. In particular, a network of small probes globally-distributed on the surface of the planet has often been cited as the only way to address this particular science goal. A team from NASA Ames has proposed such a mission called the Micrometeorology mission, or 'Micro-met' for short. Surface pressure data are all that are required, in principle, to calculate the Martian atmospheric circulation, provided that simultaneous orbital measurements of the atmosphere are also obtained. Consequently, in the proposed Micro-met mission a large number of landers would measure barometric pressure at various locations around Mars, each equipped with a micro-pressure sensor. Much of the time on the JRI was therefore spent working with the engineers and scientists concerned with Micro-met to develop this particular mission concept into a more realistic proposition.

Pulmonary function in obese vs non-obese cats.

PubMed

García-Guasch, Laín; Caro-Vadillo, Alicia; Manubens-Grau, Jordi; Carretón, Elena; Camacho, Aparecido A; Montoya-Alonso, José Alberto

2015-06-01

Obesity is a risk factor in the development of several respiratory diseases. Lung volumes tend to be decreased, especially expiratory reserve volume, increasing expiratory flow limitation during tidal breathing. Barometric whole-body plethysmography is a non-invasive pulmonary function test that allows a dynamic study of breathing patterns. The objective of this study was to compare pulmonary function variables between obese and non-obese cats through the use of barometric whole-body plethysmography. Nine normal-weight and six obese cats were placed in the plethysmograph chamber, and different respiratory variables were measured. There was a significant decrease in tidal volume per kilogram (P = 0.003), minute volume per kilogram (P = 0.001) and peak inspiratory and expiratory flows per kilogram (P = 0.001) in obese cats compared with non-obese cats. Obesity failed to demonstrate a significant increase in bronchoconstriction index variable enhanced pause (Penh), as previously reported in humans and dogs. The results show that feline obesity impairs pulmonary function in cats, although a significant increase in bronchoconstriction indexes was not observed. Non-invasive barometric whole-body plethysmography can help characterise mechanical dysfunction of the airways in obese cats. © ISFM and AAFP 2014.

Headache Attributed to Airplane Travel: A Review of Literature.

PubMed

Nierenburg, Hida; Jackfert, Katelin

2018-06-14

Headaches due to airplane travel are rare but documented in the literature. We aim to provide a review of diagnostic criteria and treatment for this condition. Several cases of this syndrome have been reported since it was first described in 2004. Airplane headache is classified as unilateral, stabbing, orbito-frontal pain, lasting under 30 min, and occurs during ascent or descent of a plane. Patients with this condition can develop anxiety and fear of flying given the intensity and severity of the pain. The pathophysiology of this syndrome is unknown, but theories include suspected barotrauma given changes in barometric pressure during ascent and descent. There are no randomized controlled trials regarding treatment, but case reports suggest headache prevention with pre-treatment with naproxen, decongestants, and triptans prior to air travel. Some non-pharmacological therapies reported include Valsalva maneuvers, chewing, relaxation techniques, and pressure at the pain area. As more cases of headache attributed to airplane travel are reported, epidemiological data can be obtained to further understand the incidence and prevalence of this condition, which can lead to improved treatment options for patients.

Experimental studies in natural groundwater recharge dynamics: Assessment of recent advances in instrumentation

USGS Publications Warehouse

Sophocleous, M.; Perry, C.A.

1984-01-01

To quantify and model the natural groundwater-recharge process, two sites in south-central Kansas, U.S.A., were instrumented with various modern sensors and data microloggers. The atmospheric-boundary layer and the unsaturated and saturated soil zones were monitored as a unified regime. Data from the various sensors were collected using microloggers in combination with magnetic-cassette tape, graphical and digital recorders, analog paper-tape recorders, and direct observations to evaluate and automate data collection and processing. Atmospheric sensors included an anemometer, a tipping-bucket raingage, an air-temperature thermistor, a relative-humidity probe, a net radiometer, and a barometric-pressure transducer. Sensors in the unsaturated zone consisted of soil-temperature thermocouples, tensiometers coupled with pressure transducers and dial gages, gypsum blocks, and a neutron moisture probe operated by an observer. The saturated-zone sensors consisted of a water-level pressure transducer, a conventional float gage connected to a variable potentiometer, soil thermocouples, and a number of multiple-depth piezometers. Evaluation of the operation of these sensors and recorders indicated that certain types of equipment such as pressure transducers are very sensitive to environmental conditions. Extraordinary steps had to be taken to protect some of the equipment, whereas other equipment seemed to be reliable under all conditions. Based on such experiences, a number of suggestions aimed at improving such investigations are outlined. ?? 1984.

Detecting dynamic causal inference in nonlinear two-phase fracture flow

NASA Astrophysics Data System (ADS)

Faybishenko, Boris

2017-08-01

Identifying dynamic causal inference involved in flow and transport processes in complex fractured-porous media is generally a challenging task, because nonlinear and chaotic variables may be positively coupled or correlated for some periods of time, but can then become spontaneously decoupled or non-correlated. In his 2002 paper (Faybishenko, 2002), the author performed a nonlinear dynamical and chaotic analysis of time-series data obtained from the fracture flow experiment conducted by Persoff and Pruess (1995), and, based on the visual examination of time series data, hypothesized that the observed pressure oscillations at both inlet and outlet edges of the fracture result from a superposition of both forward and return waves of pressure propagation through the fracture. In the current paper, the author explores an application of a combination of methods for detecting nonlinear chaotic dynamics behavior along with the multivariate Granger Causality (G-causality) time series test. Based on the G-causality test, the author infers that his hypothesis is correct, and presents a causation loop diagram of the spatial-temporal distribution of gas, liquid, and capillary pressures measured at the inlet and outlet of the fracture. The causal modeling approach can be used for the analysis of other hydrological processes, for example, infiltration and pumping tests in heterogeneous subsurface media, and climatic processes, for example, to find correlations between various meteorological parameters, such as temperature, solar radiation, barometric pressure, etc.

The lunar semidiurnal air pressure tide in in-situ data and ECMWF reanalyses

NASA Astrophysics Data System (ADS)

Schindelegger, Michael; Dobslaw, Henryk

2016-04-01

A gridded empirical model of the lunar semidiurnal air pressure tide L2 is deduced through multiquadric interpolation of more than 2000 globally distributed tidal estimates from land barometers and moored buoys. The resulting climatology serves as an independent standard to validate the barometric L2 oscillations that are present in ECMWF's (European Centre for Medium-Range Weather Forecasts) global atmospheric reanalyses despite the omission of gravitational forcing mechanisms in the involved forecast routines. Inconsistencies between numerical and empirical L2 solutions are found to be small even though the reanalysis models typically underestimate equatorial peak pressures by 10-20% and produce slightly deficient tidal phases in latitudes south of 30°N. Through using a time-invariant reference surface over both land and water and assimilating marine pressure data without accounting for vertical sensor movements due to the M2 ocean tide, ECMWF-based tidal solutions are also prone to strong local artifacts. Additionally, the dependency of the lunar tidal oscillation in atmospheric analysis systems on the meteorological input data is demonstrated based on a recent ECMWF twentieth-century reanalysis (ERA-20C) which draws its all of its observational constraints from in-situ registrations of pressure and surface winds. The L2 signature prior to 1950 is particularly indicative of distinct observing system changes, such as the paucity of marine data during both World Wars or the opening of the Panama Canal in 1914 and the associated adjustment of commercial shipping routes.

Comparison of Bacillus atrophaeus spore viability following exposure to detonation of C4 and to deflagration of halogen-containing thermites

DOE PAGES

Tringe, J. W.; Letant, S. E.; Dugan, L. C.; ...

2013-12-17

We found that energetic materials are being considered for the neutralization of spore-forming bacteria. In this study, the neutralization effects of a monomolecular explosive were compared to the effects of halogen-containing thermites. Bacillus atrophaeus spores were exposed to the post-detonation environment of a 100 g charge of the military explosive C-4 at a range of 50 cm. These tests were performed in the thermodynamically closed environment of a 506-l barometric calorimeter. Associated temperatures were calculated using a thermodynamic model informed by calculations with the Cheetah thermochemicalcode. Temperatures in the range of 2300–2800 K were calculated to persist for nearly themore » full 4 ms pressure observation time. After the detonation event, spores were characterized using optical microscopy and the number of viable spores was assessed. These results showed live spore survival rates in the range of 0.01%–1%. For the thermite tests, a similar, smaller-scale configuration was employed that examined the spore neutralization effects of two thermites: aluminum with iodine pentoxide andaluminum with potassium chlorate. Only the former mixture resulted in spore neutralization. Our results indicate that the detonation environment produced by an explosive with no chemical biocides may provide effective spore neutralization similar to a deflagrating thermite containing iodine.« less

Comparison of Bacillus atrophaeus spore viability following exposure to detonation of C4 and to deflagration of halogen-containing thermites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tringe, J. W.; Létant, S. E.; Dugan, L. C.

2013-12-21

Energetic materials are being considered for the neutralization of spore-forming bacteria. In this study, the neutralization effects of a monomolecular explosive were compared to the effects of halogen-containing thermites. Bacillus atrophaeus spores were exposed to the post-detonation environment of a 100 g charge of the military explosive C-4 at a range of 50 cm. These tests were performed in the thermodynamically closed environment of a 506-l barometric calorimeter. Associated temperatures were calculated using a thermodynamic model informed by calculations with the Cheetah thermochemical code. Temperatures in the range of 2300–2800 K were calculated to persist for nearly the full 4 ms pressure observation time.more » After the detonation event, spores were characterized using optical microscopy and the number of viable spores was assessed. Results showed live spore survival rates in the range of 0.01%–1%. For the thermite tests, a similar, smaller-scale configuration was employed that examined the spore neutralization effects of two thermites: aluminum with iodine pentoxide and aluminum with potassium chlorate. Only the former mixture resulted in spore neutralization. These results indicate that the detonation environment produced by an explosive with no chemical biocides may provide effective spore neutralization similar to a deflagrating thermite containing iodine.« less

Spatiotemporal variation of radon and carbon dioxide concentrations in an underground quarry: coupled processes of natural ventilation, barometric pumping and internal mixing.

PubMed

Perrier, Frédéric; Richon, Patrick

2010-04-01

Radon-222 and carbon dioxide concentrations have been measured during several years at several points in the atmosphere of an underground limestone quarry located at a depth of 18 m in Vincennes, near Paris, France. Both concentrations showed a seasonal cycle. Radon concentration varied from 1200 to 2000 Bq m(-3) in summer to about 800-1400 Bq m(-3) in winter, indicating winter ventilation rates varying from 0.6 to 2.5 x 10(-6) s(-1). Carbon dioxide concentration varied from 0.9 to 1.0% in summer, to about 0.1-0.3% in winter. Radon concentration can be corrected for natural ventilation using temperature measurements. The obtained model also accounts for the measured seasonal variation of carbon dioxide. After correction, radon concentrations still exhibit significant temporal variation, mostly associated with the variation of atmospheric pressure, with coupling coefficients varying from -7 to -26 Bq m(-3) hPa(-1). This variation can be accounted for using a barometric pumping model, coupled with natural ventilation in winter, and including internal mixing as well. After correction, radon concentrations exhibit residual temporal variation, poorly correlated between different points, with standard deviations varying from 3 to 6%. This study shows that temporal variation of radon concentrations in underground cavities can be understood to a satisfactory level of detail using non-linear and time-dependent modelling. It is important to understand the temporal variation of radon concentrations and the limitations in their modelling to monitor the properties of natural or artificial underground settings, and to be able to assess the existence of new processes, for example associated with the preparatory phases of volcanic eruptions or earthquakes. Copyright 2009 Elsevier Ltd. All rights reserved.

Water-quality data for selected sites on Reversed, Rush, and Alger Creeks and Gull and Silver Lakes, Mono County, California, April 1994 to March 1995

USGS Publications Warehouse

Wang, Bronwen; Rockwell, G.L.; Blodgett, J.C.

1995-01-01

Water-quality data for selected sites on Reversed, Rush, and Alger Creeks and Gull and Silver Lakes, Mono County, California, were collected from April 1994 to March 1995. Water samples were analyzed for major ions and trace elements, nutrients, methylene blue active substances, and oil and grease. Field measurements were made for discharge, specific conductance, pH, water temperature, barometric pressure, dissolved oxygen, and alkalinity. Additional data collected include vertical water profiles of specific conductance, pH, water temperature, and dissolved oxygen collected at 3.3-foot intervals for Gull and Silver Lakes; chlorophyll-a and -b concentrations and Secchi depth for Gull and Silver Lakes; sediment interstitial- water nutrient concentrations in cores from Gull Lake; and lake surface and volume of Gull and Silver Lakes.

An environmental chamber system for prolonged metabolic studies on small animals

NASA Technical Reports Server (NTRS)

Jordan, J. P.; Huston, L. J.; Simmons, J. B., II; Clarkson, D. P.; Martz, W. W.; Schatte, C. L.

1973-01-01

Measurement of metabolic adaptation to marginally stressful environments requires both precise regulation of a variety of atmospheric factors for extended periods of time and the capacity to employ sensitive parameters in an undisturbed subject. This paper describes a metabolic chamber system which can simultaneously maintain groups of small animals in two completely separate closed environments having different pressures, temperatures and gas compositions for an indefinite period. Oxygen consumption, carbon dioxide production, food and water consumption and animal activity cycles can be continuously monitored and quantified 24 h per day while the animals are in an unrestrained state. Each chamber can be serviced and the animals handled, injected and sacrificed without subjecting them to barometric stress. Several unique electrical and mechanical components allow semi-automated data collection on a continuous basis for indefinite periods of time.

Physical efficiency of Bengali farmers in response to change in environmental factors.

PubMed

Chandra, A M; Mahanta, S; Sadhu, N

1994-06-01

The present study was conducted on young farmers, selected randomly from a village of West Bengal. Their pre-exercise heart rate (HR), blood pressure (BP), mean arterial pressure (MAP), and other physical parameters were recorded. They were asked to perform standard step test at four different times of a day when environmental factors were recorded. Recorded environmental factors were maximum ambient temperature (Tmax), and minimum ambient temperature (Tmin) for the whole day, ambient temperature (Ta), relative humidity (RH), air velocity (AV), and globe temperature (Tg). The barometric pressure (P) was noted to be constant throughout the experiment. Post-exercise HR and MAP were also recorded. Our observations showed that environmental factors changed as the day progressed from the morning to noon and from noon to night; the physiological parameters of the farmers also changed. HR was lowest in the morning and night but highest in the evening while MAP was highest at midday and gradually returned to the pre-exercise level by the evening. The determined Physical Fitness Index (PFI) of the farmers was noted to be lowest at midday but highest at night. Our studies indicate that environmental factors have a role on the physical efficiency of farmers. Ta, RH and Tg appear to be primarily responsible for the alterations in the physiological functions and PFI.

Endotracheal tube and laryngeal mask airway cuff volume changes with altitude: a rule of thumb for aeromedical transport.

PubMed

Mann, Catherine; Parkinson, Neil; Bleetman, Anthony

2007-03-01

Helicopters and light (unpressurised) aircraft are used increasingly for the transport of ventilated patients. Most of these patients are ventilated through endotracheal tubes (ETTs), others through laryngeal mask airways (LMAs). The cuffs of both ETTs and LMAs inflate with increases in altitude as barometric pressure decreases (30 mbar/1000 feet). Tracheal mucosa perfusion becomes compromised at a pressure of approximately 30 cm H2O; critical perfusion pressure is 50 cm H2O. The change in dimensions of the inflated cuffs of a size 8 ETT and a size 5 LMA were measured with digital callipers at 1000 feet intervals in the unpressurised cabin of an Agusta 109 helicopter used by the Warwickshire and Northamptonshire Air Ambulance. A linear expansion in cuff dimensions as a function of altitude increase was identified. For ETTs, a formula for removal of air from the cuff with increasing altitude was calculated and is recommended for use in aeromedical transfers. This is 1/17x1.1 = 0.06 ml/1000 foot ascent/ml initial cuff inflation. The data for LMA cuff expansion failed to show significant correlation with altitude change. Further work is required to determine a similar rule of thumb for LMA cuff deflation.

Barodontalgia as a differential diagnosis: symptoms and findings.

PubMed

Robichaud, Roland; McNally, Mary E

2005-01-01

This paper provides a review of the literature concerning the etiology and manifestations of barodontalgia, as well as important clinical considerations for its management. Barodontalgia is characterized by exposure to a pressure gradient, such as that experienced by underwater divers, aviation personnel and air travellers. This form of dental pain is generally marked by a predisposing dental pathology such as acute or chronic periapical infection, caries, deep or failing restorations, residual dental cysts, sinusitis or a history of recent surgery. Studies indicate that severity of barodontalgia and the resulting deterioration of dental health correlates with duration of barometric stress. Restorative materials are also affected by pressure gradients. Resin is indicated as a luting agent of choice for cementing fixed prostheses in populations at risk for barodontalgia. Under the influence of pressure gradients, resin cements maintain original bond strength and demonstrate the least amount of microleakage compared with other cements. The key to avoiding barodontalgia is good oral health. Clinicians must pay close attention to areas of dentin exposure, caries, fractured cusps, the integrity of restorations and periapical pathology in those at risk. The Fédération dentaire internationale describes 4 classes of barodontalgia based on signs and symptoms and provides specific and valuable recommendations for therapeutic intervention.

Ring-shaped pulse oximeter and its application: measurement of SpO2 and blood pressure during sleep and during flight.

PubMed

Kishimoto, Aya; Tochikubo, Osamu; Ohshige, Kenji; Yanaga, Akihiko

2005-01-01

Respiratory and cardiovascular functions show circadian and day-to-day changes. We have developed a wireless ring-shaped pulse oximeter in collaboration with MC Medical Inc. and Advanced Medical Inc. We investigated the accuracy of this pulse oximeter and its application in daily life. Percutaneous arterial oxygen saturation (SpO2) of 47 volunteers was measured simultaneously with the ring-shaped pulse oximeter and a standard pulse oximeter. A total of 103 volunteers underwent measurement of SpO2 for 24 hr, and 11 healthy volunteers underwent measurement of SpO2 and blood pressure (BP) during flight. SpO2 and heart rate (HR) were measured and recorded every 20 sec, cabin barometric pressure and cabin oxygen concentration equivalent to sea level were measured minute-to-minute, and BP was measured every 3 min with a portable BP recorder during each flight. The SpO2 values measured with the ring-shaped pulse oximeter were similar to those measured with the standard method. The mean SpO2 during sleep was significantly lower in the group with high-normal BP or mild hypertension than in the group with normal BP. During flight, the mean change in SpO2 was -2.4 +/- 1.7% during nose-up flight, and 2.1 +/- 2.6% during nose-down flight. There was a significant correlation between change in SpO2 and change in systolic BP during nose-up flight. The wireless ring-shaped pulse oximeter was useful for investigating changes in SpO2 and its effect on BP in daily life during sleep and during air travel.

[The clinical research of aviatic nasal diseases with medical evaluation prevention and control intervention].

PubMed

Wang, Binru; Xu, Xianrong; Jin, Zhangguo; Zhang, Yang

2015-03-01

Exploring the clinical features of aviatic nasal diseases to provide references for medical evaluation, prevention and control measures in aircrew. To analysis and summary 605 cases with 503 pilots of nasal diseases in aircrew during 1966 to 2013. (1) There were 605 cases of aviatic nasal diseases, including 550 cases of general diseases and 55 cases of specific diseases. The general nasal diseases included 140 cases of anatomical abnormalities in nasal cavity type, 290 cases of inflammation in nasal cavity, 73 cases of allergy type, 47 cases of cyst and tumor type, and the specific nasal diseases were 55 cases of sinus barotrauma (SB). (2) The, constituent ratio of SB, which was happened in frontal sinus and /or maxillary sinus, was 95.55%. (3) The constituent ratio of cyst and tumor type in nasal cavity was easier causing to SB than anatomical abnormalities, inflammation, allergy disease in nasal cavity (P < 0.05). (4) The grounded constituent ratio of secondary SB was higher than anatomical abnormalities, inflammation, allergy, cyst and tumor disease in nasal cavity (P < 0.05). (5) The ways of hypobaric chamber tests were different for the kinds of aircrew. The qualified adjustment function of sinuses for barometric pressure was an essential condition for aircrew to continue flying. (6) The key point for the treatment of aviatic nasal diseases was to remove pathological change in nasal cavity and sinus and restore sinus ostium patency. The key point for the medical evaluation was to restore normal sinus pressure balance function. The key point of medical evaluation about aviatic nasal diseases is to assess the sinus pressure balance function in hypobaric chamber tests. Normative treatment and medical evaluation can effectively avoid flight accidents and improve the attendance rate for aircrew.

Meteorological responses in the atmospheric boundary layer over southern England to the deep partial eclipse of 20 March 2015.

PubMed

Burt, Stephen

2016-09-28

A wide range of surface and near-surface meteorological observations were made at the University of Reading's Atmospheric Observatory in central southern England (latitude 51.441° N, longitude 0.938° W, altitude 66 m above mean sea level) during the deep partial eclipse on the morning of 20 March 2015. Observations of temperature, humidity, radiation, wind speed and direction, and atmospheric pressure were made by computerized logging equipment at 1 Hz, supplemented by an automated cloud base recorder sampling at 1 min intervals and a high-resolution (approx. 10 m vertical interval) atmospheric sounding by radiosonde launched from the same location during the eclipse. Sources and details of each instrumental measurement are described briefly, followed by a summary of observed and derived measurements by meteorological parameter. Atmospheric boundary layer responses to the solar eclipse were muted owing to the heavily overcast conditions which prevailed at the observing location, but instrumental records of the event documented a large (approx. 80%) reduction in global solar radiation, a fall in air temperature of around 0.6°C, a decrease in cloud base height, and a slight increase in atmospheric stability during the eclipse. Changes in surface atmospheric moisture content and barometric pressure were largely insignificant during the event.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Author(s).

Meteorological responses in the atmospheric boundary layer over southern England to the deep partial eclipse of 20 March 2015

PubMed Central

2016-01-01

A wide range of surface and near-surface meteorological observations were made at the University of Reading’s Atmospheric Observatory in central southern England (latitude 51.441° N, longitude 0.938° W, altitude 66 m above mean sea level) during the deep partial eclipse on the morning of 20 March 2015. Observations of temperature, humidity, radiation, wind speed and direction, and atmospheric pressure were made by computerized logging equipment at 1 Hz, supplemented by an automated cloud base recorder sampling at 1 min intervals and a high-resolution (approx. 10 m vertical interval) atmospheric sounding by radiosonde launched from the same location during the eclipse. Sources and details of each instrumental measurement are described briefly, followed by a summary of observed and derived measurements by meteorological parameter. Atmospheric boundary layer responses to the solar eclipse were muted owing to the heavily overcast conditions which prevailed at the observing location, but instrumental records of the event documented a large (approx. 80%) reduction in global solar radiation, a fall in air temperature of around 0.6°C, a decrease in cloud base height, and a slight increase in atmospheric stability during the eclipse. Changes in surface atmospheric moisture content and barometric pressure were largely insignificant during the event. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550762

Building an Efficient Model for Afterburn Energy Release

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alves, S; Kuhl, A; Najjar, F

2012-02-03

Many explosives will release additional energy after detonation as the detonation products mix with the ambient environment. This additional energy release, referred to as afterburn, is due to combustion of undetonated fuel with ambient oxygen. While the detonation energy release occurs on a time scale of microseconds, the afterburn energy release occurs on a time scale of milliseconds with a potentially varying energy release rate depending upon the local temperature and pressure. This afterburn energy release is not accounted for in typical equations of state, such as the Jones-Wilkins-Lee (JWL) model, used for modeling the detonation of explosives. Here wemore » construct a straightforward and efficient approach, based on experiments and theory, to account for this additional energy release in a way that is tractable for large finite element fluid-structure problems. Barometric calorimeter experiments have been executed in both nitrogen and air environments to investigate the characteristics of afterburn for C-4 and other materials. These tests, which provide pressure time histories, along with theoretical and analytical solutions provide an engineering basis for modeling afterburn with numerical hydrocodes. It is toward this end that we have constructed a modified JWL equation of state to account for afterburn effects on the response of structures to blast. The modified equation of state includes a two phase afterburn energy release to represent variations in the energy release rate and an afterburn energy cutoff to account for partial reaction of the undetonated fuel.« less

Semianalytical model predicting transfer of volatile pollutants from groundwater to the soil surface.

PubMed

Atteia, Olivier; Höhener, Patrick

2010-08-15

Volatilization of toxic organic contaminants from groundwater to the soil surface is often considered an important pathway in risk analysis. Most of the risk models use simplified linear solutions that may overpredict the volatile flux. Although complex numerical models have been developed, their use is restricted to experienced users and for sites where field data are known in great detail. We present here a novel semianalytical model running on a spreadsheet that simulates the volatilization flux and vertical concentration profile in a soil based on the Van Genuchten functions. These widely used functions describe precisely the gas and water saturations and movement in the capillary fringe. The analytical model shows a good accuracy over several orders of magnitude when compared to a numerical model and laboratory data. The effect of barometric pumping is also included in the semianalytical formulation, although the model predicts that barometric pumping is often negligible. A sensitivity study predicts significant fluxes in sandy vadose zones and much smaller fluxes in other soils. Fluxes are linked to the dimensionless Henry's law constant H for H < 0.2 and increase by approximately 20% when temperature increases from 5 to 25 degrees C.

[Is olfactory function impaired in moderate height?].

PubMed

Kühn, M; Welsch, H; Zahnert, T; Hummel, Thomas

2009-09-01

The human sense of smell seems to be influenced by the surrounding barometric pressure. These factors appear to be especially important during flights, for example, in order to recognize the smell of fire etc. Thus, questions are whether pilots or passengers exhibit an impaired smell sensitivity when tested at moderate heights, or, whether changes in humidity would affect the sense of smell. Using climate chambers, odor discrimination and butanol odor thresholds were tested in 77 healthy normosmic volunteers (5 female, 72 male; aged 25+/-8 years from 18 up to 53 years) under hypobaric (2 700+/-20 m, 20 degrees C+/-1 K, rh=50+/-5%) and hyperbaric, (10+/-0.5 m (2 bar)) and different humidity conditions (30 vs. 80%, 20 degrees C+/-1 K, normobaric). During all conditions cognitive performance was tested. Among other effects, olfactory sensitivity was impaired at threshold, but not suprathreshold level, in a hypobaric compared to a hyperbaric milieu, and thresholds were lower in humid, compared to relatively dry conditions. In conclusion, environmental conditions modulate the sense of smell, and may, consecutively, influence results from olfactory tests. During flight hypobaric conditions, mild hypoxia and dry air may cause impaired sensitivity of smell. Georg Thieme Verlag KG Stuttgart * New York.

Interaction and influence of two creeks on Escherichia coli concentrations of nearby beaches: Exploration of predictability and mechanisms

USGS Publications Warehouse

Nevers, M.B.; Whitman, R.L.; Frick, W.E.; Ge, Z.

2007-01-01

The impact of river outfalls on beach water quality depends on numerous interacting factors. The delivery of contaminants by multiple creeks greatly complicates understanding of the source contributions, especially when pollution might originate up- or down-coast of beaches. We studied two beaches along Lake Michigan that are located between two creek outfalls to determine the hydrometeorologic factors influencing near-shore microbiologic water quality and the relative impact of the creeks. The creeks continuously delivered water with high concentrations of Escherichia coli to Lake Michigan, and the direction of transport of these bacteria was affected by current direction. Current direction reversals were associated with elevated E. coli concentrations at Central Avenue beach. Rainfall, barometric pressure, wave height, wave period, and creek specific conductance were significantly related to E. coli concentration at the beaches and were the parameters used in predictive models that best described E. coli variation at the two beaches. Multiple inputs to numerous beaches complicates the analysis and understanding of the relative relationship of sources but affords opportunities for showing how these complex creek inputs might interact to yield collective or individual effects on beach water quality.

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacVean, D.W.; Franzen, D.K.; Keefe, T.J.

To elucidate the role of air quality on the occurrence of pneumonia in feedlot cattle, the following environmental values were measured at a feedlot: suspended particulates in 5 particle-size fractions, relative humidity, air temperature, and barometric pressure. Pneumonia incidence data were classified by the number of days the cattle had been at the feedlot (days on feed). The concentration of airborne particles, range of temperature, days on feed, and season of the year were associated with incidence of pneumonia in cattle. Pneumonia incidence rates were greatest both within 15 days of arrival at the feedlot and during the fall samplingmore » periods. The incidence of pneumonia in the 16 to 30 days-on-feed group was closely associated with the concentration of particles 2.0 to 3.3 microns in diameter and the range of daily temperature when exposure occurred 15 days before the onset of disease in the fall and 10 days before in the spring.« less

The Development of Wireless Body Area Network for Motion Sensing Application

NASA Astrophysics Data System (ADS)

Puspitaningayu, P.; Widodo, A.; Yundra, E.; Ramadhany, F.; Arianto, L.; Habibie, D.

2018-04-01

The information era has driven the society into the digitally-controlled lifestyle. Wireless body area networks (WBAN) as the specific scope of wireless sensor networks (WSN) is consistently growing into bigger applications. Currently, people are able to monitor their medical parameters by simply using small electronics devices attached to their body and connected to the authorities. On top of that, this time, smart phones are typically equipped with sensors such as accelerometer, gyroscope, barometric pressure, heart rate monitor, etc. It means that the sensing yet the signal processing can be performed by a single device. Moreover, Android opens lot wider opportunities for new applications as the most popular open-sourced smart phone platform. This paper is intended to show the development of motion sensing application which focused on analysing data from accelerometer and gyroscope. Beside reads the sensors, this application also has the ability to convert the sensors’ numerical value into graphs.

Geometeorological data collected by the USGS Desert Winds Project at Desert Wells, Sonoran Desert, central-west Arizona, 1981 - 1996

USGS Publications Warehouse

Helm, Paula J.; Breed, Carol S.; Tigges, Richard; Creighton, Shawn

1998-01-01

The data in this report were obtained by instruments deployed on a GOES-satellite data collection station operated by the U.S. Geological Survey Desert Winds Project at Desert Wells (latitude 33° 42' 08" N, longitude 113° 48' 40" W), La Paz County, west-central Arizona. The elevation is 344 m (1,130 ft). From January 9, 1981 through May 31, 1995 the station recorded eight parameters: wind direction, wind speed, peak gust, air temperature, precipitation, humidity, barometric pressure, and soil temperature. On June 1, 1995, the station was upgraded by adding a SENSIT sand-flux sensor, which records grain impacts concurrently with wind speed and wind direction measurements. Included with the data is descriptive text on the geology, soils, climate, vegetation, and land use at the site, as well as text on data format, date retrieval software and instructions, and metadata

Revised forecast: Another stormy summer ahead

NASA Astrophysics Data System (ADS)

Carlowicz, Michael

After predicting in November 1995 that the 1996 hurricane season would be less active than the typical year (Eos, December 12, 1995), William Gray and his colleagues from Colorado State University have revised their forecast. Plugging updated atmospheric data into their statistical model, the researchers are now predicting seven hurricanes—two of them intense (category 3, 4, or 5)—and 11 named storms for the summer and fall of 1996. Net tropical cyclone activity for the hurricane season, which lasts from June 1 to December 1, should be 105% of the 25-year average, according to Gray.In November, Gray and Chris Landsea of NOAA's Hurricane Research Division predicted eight tropical storms and five hurricanes (two intense), less than the historical averages of 9.3 named storms and 5.7 hurricanes per season. The change in expectations is the result of new accounting for trends in temperature and barometric pressure in Africa and around the Atlantic Basin.

Weather and Death on Mount Everest: Is there a link between Storms and Human Physiology?

NASA Astrophysics Data System (ADS)

Moore, K.; Semple, J.

2004-05-01

Scientific interest in Mount Everest has been largely focused on the hypoxia caused by the summit's low barometric pressure. Although weather is recognized as a significant risk factor, it has not been extensively studied. Through the use of observations made at the mountain's South Col, elevation 7986m, and other datasets, we show that high impact weather events on Mount Everest, including the May 1996 storm in which 8 climbers perished, are often associated with continental-scale intrusions of stratospheric air into the upper-troposphere. The variability in wind speeds associated with these intrusions triggered convective activity that resulted in the high impact weather. In addition, the validation of existing meteorological data allows for useful insights into the possibility of forecasting these high impact weather events and their physiological impacts thereby mitigating deaths that occur on the exposed upper slopes of Mount Everest.

Operating and environmental characteristics of Sigma Tau hydrogen masers used in the Very Long Baseline Array (VLBA)

NASA Technical Reports Server (NTRS)

Tucker, T. K.

1989-01-01

Presented here are the results obtained from performance evaluation of a pair of Sigma Tau Standards Corporation Model VLBA-112 active hydrogen maser frequency standards. These masers were manufactured for the National Radio Astronomy Observatory (NRAO) for use on the Very Long Baseline Array (VLBA) project and were furnished to the Jet Propulsion Laboratory (JPL) for the purpose of these tests. Tests on the two masers were performed in the JPL Frequency Standards Laboratory (FSL) and included the characterization of output frequency stability versus environmental factors such as temperature, humidity, magnetic field, and barometric pressure. The performance tests also included the determination of phase noise and Allan variance using both FSL and Sigma Tau masers as references. All tests were conducted under controlled laboratory conditions, with only the desired environmental and operational parameters varied to determine sensitivity to external environment.

Water-Quality Data for Selected Stream Sites in Bridgeport Valley, Mono County, California, April 2000 to June 2003

USGS Publications Warehouse

Rockwell, Gerald L.; Honeywell, Paul D.

2004-01-01

The U.S. Geological Survey, in cooperation with the California Regional Water Quality Control Board, Lahonton Region, carried out a water-quality data collection program of selected streams in and near Bridgeport Valley, California, during April 2000 to June 2003. These data were collected to provide information used by the California Regional Water Quality Control Board to develop total maximum daily load standards. Field measurements of streamflow, barometric pressure, dissolved oxygen, pH, specific conductance, and water temperature were made at 15 sites located on 6 streams. Water samples were analyzed for nutrients, major ions, turbidity, fecal coliform, fecal streptococci, and suspended sediment. Field data, turbidity, nutrient, major ion, and sediment concentrations and fecal coliform and fecal streptococci densities are given in tables for each site. Field blank data are also presented in a table.

Measuring and computing natural ground-water recharge at sites in south-central Kansas

USGS Publications Warehouse

Sophocleous, M.A.; Perry, C.A.

1987-01-01

To measure the natural groundwater recharge process, two sites in south-central Kansas were instrumented with sensors and data microloggers. The atmospheric-boundary layer and the unsaturated and saturated soil zones were monitored as a single regime. Direct observations also were used to evaluate the measurements. Atmospheric sensors included an anemometer, a tipping-bucket rain gage, an air-temperature thermistor, a relative-humidity probe, a net radiometer, and a barometric-pressure transducer. Sensors in the unsaturated zone consisted of soil-temperature thermocouples, tensiometers coupled with pressure transducers and dial gages, gypsum blocks, and a neutron-moisture probe. The saturated-zone sensors consisted of a water-level pressure transducer, a conventional float gage connected to a variable potentiometer, soil thermocouples, and a number of multiple-depth piezometers. Evaluation of the operation of these sensors and recorders indicates that certain types of equipment, such as pressure transducers, are very sensitive to environmental conditions. A number of suggestions aimed at improving instrumentation of recharge investigations are outlined. Precipitation and evapotranspiration data, taken together with soil moisture profiles and storage changes, water fluxes in the unsaturated zone and hydraulic gradients in the saturated zone at various depths, soil temperature, water table hydrographs, and water level changes in nearby wells, describe the recharge process. Although the two instrumented sites are located in sand-dune environments in area characterized by a shallow water table and a sub-humid continental climate, a significant difference was observed in the estimated total recharge. The estimates ranged from less than 2.5 mm at the Zenith site to approximately 154 mm at the Burrton site from February to June 1983. The principal reasons that the Burrton site had more recharge than the Zenith site were more precipitation, less evapotranspiration, and a shallower depth to the water table. Effective recharge took place only during late winter and spring. No summer or fall recharge was observed at either site during the observation period of this study. (Author 's abstract)

Hydrologic and geochemical monitoring in Long Valley Caldera, Mono County, California, 1985

USGS Publications Warehouse

Farrar, C.D.; Sorey, M.L.; Rojstaczer, S.A.; Janik, C.J.; Winnett, T.L.; Clark, M.D.

1987-01-01

Hydrologic and geochemical monitoring, to detect changes caused by magmatic and tectonic processes in the Long Valley caldera has continued through 1985. The monitoring included the collection of the following types of data: chemical and isotopic composition of water and gases from springs, wells, and steam vents; temperatures in wells, springs, and steam vents; flow rates of springs and streams; water levels in wells; and barometric pressure and precipitation at several sites. In addition, reservoir temperatures for the geothermal system were estimated from computations based on chemical geothermometers applied to fluid samples from wells and springs. Estimates of thermal water discharged from springs were made on the basis of boron and chloride fluxes in surface waters for selected sites in the Casa Diablo area and along the Mammoth-Hot Creek drainage. These data are presented in tables and graphs. The Long Valley area was relatively quiescent throughout 1985 in terms of geodetic changes and seismic activity. As a consequence , the hydrologic system varied mainly in response to seasonal influences of temperature, atmospheric pressure, and precipitation. However, spring flows near Casa Diablo were influenced by pumping at the geothermal production well field nearby. (Author 's abstract)

FIRE_AX_UKMO_C130

Atmospheric Science Data Center

2015-11-25

... FSSP Gust Probe Hot-Wire Hygrometer Platinum Resistance PMS 2D-C Probe PRT-4 Pyranometer Pyrgeometer ... Parameters:  Barometric Altitude Cloud Top Temperature Deiced Temperature Dew/Frost Point Temperature Droplet ...

Content of total iron, copper and manganese in liver of animals during hypokinesia, muscle activity and process of recovery

NASA Technical Reports Server (NTRS)

Potapovich, G. M.; Taneyeva, G. V.; Uteshev, A. B.

1980-01-01

It is shown that the content of total iron, copper and manganese in the liver of animals is altered depending on the intensity and duration of their swimming. Hypodynamia for 7 days does not alter the concentration of iron, but sufficiently increases the content of copper and manganese. The barometric factor effectively influences the maintenance of constancy in the content of microelements accumulated in the liver after intensive muscle activity.

Improving activity recognition using a wearable barometric pressure sensor in mobility-impaired stroke patients.

PubMed

Massé, Fabien; Gonzenbach, Roman R; Arami, Arash; Paraschiv-Ionescu, Anisoara; Luft, Andreas R; Aminian, Kamiar

2015-08-25

Stroke survivors often suffer from mobility deficits. Current clinical evaluation methods, including questionnaires and motor function tests, cannot provide an objective measure of the patients' mobility in daily life. Physical activity performance in daily-life can be assessed using unobtrusive monitoring, for example with a single sensor module fixed on the trunk. Existing approaches based on inertial sensors have limited performance, particularly in detecting transitions between different activities and postures, due to the inherent inter-patient variability of kinematic patterns. To overcome these limitations, one possibility is to use additional information from a barometric pressure (BP) sensor. Our study aims at integrating BP and inertial sensor data into an activity classifier in order to improve the activity (sitting, standing, walking, lying) recognition and the corresponding body elevation (during climbing stairs or when taking an elevator). Taking into account the trunk elevation changes during postural transitions (sit-to-stand, stand-to-sit), we devised an event-driven activity classifier based on fuzzy-logic. Data were acquired from 12 stroke patients with impaired mobility, using a trunk-worn inertial and BP sensor. Events, including walking and lying periods and potential postural transitions, were first extracted. These events were then fed into a double-stage hierarchical Fuzzy Inference System (H-FIS). The first stage processed the events to infer activities and the second stage improved activity recognition by applying behavioral constraints. Finally, the body elevation was estimated using a pattern-enhancing algorithm applied on BP. The patients were videotaped for reference. The performance of the algorithm was estimated using the Correct Classification Rate (CCR) and F-score. The BP-based classification approach was benchmarked against a previously-published fuzzy-logic classifier (FIS-IMU) and a conventional epoch-based classifier (EPOCH). The algorithm performance for posture/activity detection, in terms of CCR was 90.4 %, with 3.3 % and 5.6 % improvements against FIS-IMU and EPOCH, respectively. The proposed classifier essentially benefits from a better recognition of standing activity (70.3 % versus 61.5 % [FIS-IMU] and 42.5 % [EPOCH]) with 98.2 % CCR for body elevation estimation. The monitoring and recognition of daily activities in mobility-impaired stoke patients can be significantly improved using a trunk-fixed sensor that integrates BP, inertial sensors, and an event-based activity classifier.

Geochemical monitoring of Taal volcano (Philippines) by means of diffuse CO2 degassing studies

NASA Astrophysics Data System (ADS)

Padrón, Eleazar; Hernández, Pedro A.; Arcilla, Carlo; Pérez, Nemesio M.; Lagmay, Alfredo M.; Rodríguez, Fátima; Quina, Gerald; Alonso, Mar; Padilla, Germán D.; Aurelio, Mario A.

2017-04-01

Observing changes in the discharge rate of CO2 is an important part of volcanic monitoring programs, because it is released by progressive depressurization of magma during ascent and reach the surface well before their parental magma. Taal Volcano in Southwest Luzon, Philippines, lies between a volcanic arc front facing the subduction zone along the Manila Trench and a volcanic field formed from extension beyond the arc front. Taal Volcano Island is formed by a main tuff cone surrounded by several smaller tuff cones, tuff rings and scoria cones. This island is located in the center of the 30 km wide Taal Caldera, now filled by Taal Lake. To monitor the volcanic activity of Taal volcano is a priority task in the Philippines, because several million people live within a 20-km radius of Taal's caldera rim. During the last period of volcanic unrest from 2010 to 2011, the main crater lake of Taal volcano released the highest diffuse CO2 emission rates through the water surface reported to date by volcanic lakes worldwide. The maximum CO2 emission rate measured in the study period occurred two months before the strongest seismic activity recorded during the unrest period (Arpa et al., 2013, Bull Volcanol 75:747). After the unrest period, diffuse CO2 emission has remained in the range 532-860 t/d in the period 2013-2016. In January 2016, an automatic geochemical station to monitor in a continuous mode the diffuse CO2 degassing in a selected location of Taal, was installed in January 2016 to improve the early warning system at the volcano. The station is located at Daang Kastila, at the northern portion of the main crater rim. It measures hourly the diffuse CO2 efflux, atmospheric CO2 concentration, soil water content and temperature, wind speed and direction, air temperature and humidity, rainfall, and barometric pressure. The 2016 time series show CO2 efflux values in the range 20-690 g m-2 d-1.Soil temperature, heavily influenced by rainfall, ranged between 74 and 96oC. Although short-temp fluctuations in the diffuse CO2 emission time series at Daang Kastila were partially driven by meteorological parameters, the main CO2 efflux changes were not driven by fluctuations of meteorological variables such as wind speed or barometric pressure and seem clearly to be associated with fluid pressure fluctuations in the volcanic system. These results showed the potential of applying continuous and discrete monitoring of soil CO2 efflux to improve and optimize the detection of early warning signals of future volcanic unrest at Taal volcano.

The effect of hypobaric hypoxia on multichannel EEG signal complexity.

PubMed

Papadelis, Christos; Kourtidou-Papadeli, Chrysoula; Bamidis, Panagiotis D; Maglaveras, Nikos; Pappas, Konstantinos

2007-01-01

The objective of this study was the development and evaluation of nonlinear electroencephalography parameters which assess hypoxia-induced EEG alterations, and describe the temporal characteristics of different hypoxic levels' residual effect upon the brain electrical activity. Multichannel EEG, pO2, pCO2, ECG, and respiration measurements were recorded from 10 subjects exposed to three experimental conditions (100% oxygen, hypoxia, recovery) at three-levels of reduced barometric pressure. The mean spectral power of EEG under each session and altitude were estimated for the standard bands. Approximate Entropy (ApEn) of EEG segments was calculated, and the ApEn's time-courses were smoothed by a moving average filter. On the smoothed diagrams, parameters were defined. A significant increase in total power and power of theta and alpha bands was observed during hypoxia. Visual interpretation of ApEn time-courses revealed a characteristic pattern (decreasing during hypoxia and recovering after oxygen re-administration). The introduced qEEG parameters S1 and K1 distinguished successfully the three hypoxic conditions. The introduced parameters based on ApEn time-courses are assessing reliably and effectively the different hypoxic levels. ApEn decrease may be explained by neurons' functional isolation due to hypoxia since decreased complexity corresponds to greater autonomy of components, although this interpretation should be further supported by electrocorticographic animal studies. The introduced qEEG parameters seem to be appropriate for assessing the hypoxia-related neurophysiological state of patients in the hyperbaric chambers in the treatment of decompression sickness, carbon dioxide poisoning, and mountaineering.

Infrared spectra alteration in water proximate to the palms of therapeutic practitioners.

PubMed

Schwartz, Stephan A; De Mattei, Randall J; Brame, Edward G; Spottiswoode, S James P

2015-01-01

Through standard techniques of infrared (IR) spectrophotometry, sterile water samples in randomly selected sealed vials evidence alteration of infrared (IR) spectra after being proximate to the palms of the hands of both Practicing and Non-practicing Therapy Practitioners, each of whom employed a personal variation of the Laying-on-of-Hands/Therapeutic Touch processes. This pilot study presents 14 cases, involving 14 Practitioners and 14 Recipients. The first hypothesis, that a variation in the spectra of all (84) Treated spectra compared with all (57) Control spectra would be observed in the 2.5-3.0µm range, was confirmed (P = .02). Overall, 10% (15) of the spectra were done using a germanium internal reflection element (IRE), and 90% of the spectra (126) were done with a zinc selenide IRE. The difference in refractive index between the two IREs skews the data. The zinc selenide IRE spectra alone yield P = .005. The authors believe the most representative evidence for the effect appeared in the sample group of Treated vs Calibration Controls using the zinc selenide IRE (P = .0004). The second hypothesis, that there existed a direct relationship between intensity of effect and time of exposure, was not confirmed. This study replicates earlier findings under conditions of blindness, randomicity, and several levels of controls. Environmental factors are considered as explanations for the observed IR spectrum alteration, including temperature, barometric pressure, and variations dependent on sampling order. They do not appear to explain the effect. Copyright © 2015. Published by Elsevier Inc.

Local weather is associated with rates of online searches for musculoskeletal pain symptoms.

PubMed

Telfer, Scott; Obradovich, Nick

2017-01-01

Weather conditions are commonly believed to influence musculoskeletal pain, however the evidence for this is mixed. This study aimed to examine the relationship between local meteorological conditions and online search trends for terms related to knee pain, hip pain, and arthritis. Five years of relative online search volumes for these terms were obtained for the 50 most populous cities in the contiguous United States, along with corresponding local weather data for temperature, relative humidity, barometric pressure, and precipitation. Methods from the climate econometrics literature were used to assess the casual impact of these meteorological variables on the relative volumes of searches for pain. For temperatures between -5°C and 30°C, search volumes for hip pain increased by 12 index points, and knee pain increased by 18 index points. Precipitation had a negative effect on search volumes for these terms. At temperatures >30°C, search volumes for arthritis related pain decreased by 7 index points. These patterns were not seen for pain searches unrelated to the musculoskeletal system. In summary, selected local weather conditions are significantly associated with online search volumes for specific musculoskeletal pain symptoms. We believe the predominate driver for this to be the relative changes in physical activity levels associated with meteorological conditions.

An Autonomous, Low Cost Platform for Seafloor Geodetic Observations

NASA Astrophysics Data System (ADS)

Ericksen, T.; Foster, J. H.; Bingham, B. S.; Oshiro, J.

2015-12-01

The Pacific GPS Facility and the Field Robotics Laboratory at the University of Hawaii have developed an approach to significantly reduce the costs of accurately measuring short-term vertical motions of the seafloor and maintaining a continuous long-term record of seafloor pressure. Traditional ship-based methods of acquiring these measurements are often prohibitively expensive. Our goal has been to reduce the primary barrier preventing us from acquiring the observations we need to understand geodetic processes, and the hazards they present, at subduction zones, submarine volcanoes, and subsea landslides. To this end, we have designed a payload package for the University of Hawaii Wave Glider which incorporates an acoustic telemetry package, a dual frequency geodetic-grade Global Positioning System (GPS) receiver, meteorological sensors, processing computer, and cellular communications. The Wave Glider is able to interrogate high accuracy pressure sensors on the seafloor to maintain a near-continuous stream of ocean bottom pressure and temperature data. The Wave Glider also functions as an integral part of the seafloor geodetic observing system, recording accurate sea surface elevations and barometric pressure; direct measurements of two of the primary sources of seafloor pressure change. The seafloor geodetic monument seats a sensor capable of recording pressure, temperature, and sound velocity for a deployment duration of over 5 years with an acoustic modem for communications, and an integral acoustic release for recovery and replacement of batteries. The design of the geodetic monument allows for precise repositioning of the sensor to extend the pressure record beyond a single 5+ year deployment, and includes the capability to install a mobile pressure recorder for calibration of the linear drift of the continuous pressure sensor. We will present the results of our field tests and an assessment of our ability to determine cm-scale vertical seafloor motions by integrating our seafloor pressure measurements with the independent Wave Glider measurements of sea surface pressure and sea surface height. An overall summary of the performance and costs of making seafloor geodetic measurement with this system will be provided.

Sandia Research and Development Board: Minutes of the 33rd Meeting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Castle, M.

1950-02-08

Notes about the barometric fuzing system testing, drops of stockpile weapons requested by the Strategic Air Command, simultaneous drops and the interaction of the baro systems, changes of desired military characteristics of atomic weapons.

Development and application of a long dynamic range nitrous oxide monitoring system.

PubMed

Ward, B G

1985-12-01

The laboratory and field evaluation of a nitrous oxide monitor for an extremely wide range of cumulative exposures are reviewed. The passive sampling behavior and high analyte capacity show it to be useful for short-term and full workweek exposure monitoring. The monitor has application for both area and personnel surveillance. The principal criterion is for an accurate report of exposure time of the monitor. Application of the monitor to real workplace environments--with and without a reference method--demonstrated the ability of workweek monitoring as a valuable and potentially superior way of documenting exposure stress of employees. Environmental factors such as humidity and temperature variation are shown to have acceptably small effects on both short- and long-term exposure data; barometric pressure affects the data in a predictable manner. Paired dosimeters show good agreement in the workplace environment throughout the range of 6-40 cumulative hours of exposure. In both hospital and dental operating suites, work logistics and work group relationships were readily traceable on a week-by-week basis during a continuous weekly monitoring program. Source emissions and appropriate worker and work area exposure relationships were clearly evident, with appropriate reduction of all exposures as a result of an abbreviated work schedule. The ability to effectively track employee and area exposure excursions in an integrated weekly manner leads to a whole series of new applications and concepts of industrial hygiene surveillance. Such approaches could effectively replace the speculative statistical approaches currently in use with actual data on a cost effective basis.

Results of hydrologic monitoring on landslide-prone coastal bluffs near Mukilteo, Washington

USGS Publications Warehouse

Smith, Joel B.; Baum, Rex L.; Mirus, Benjamin B.; Michel, Abigail R.; Stark, Ben

2017-08-31

A hydrologic monitoring network was installed to investigate landslide hazards affecting the railway corridor along the eastern shore of Puget Sound between Seattle and Everett, near Mukilteo, Washington. During the summer of 2015, the U.S. Geological Survey installed monitoring equipment at four sites equipped with instrumentation to measure rainfall and air temperature every 15 minutes. Two of the four sites are installed on contrasting coastal bluffs, one landslide scarred and one vegetated. At these two sites, in addition to rainfall and air temperature, volumetric water content, pore pressure, soil suction, soil temperature, and barometric pressure were measured every 15 minutes. The instrumentation was designed to supplement landslide-rainfall thresholds developed by the U.S. Geological Survey with a long-term goal of advancing the understanding of the relationship between landslide potential and hydrologic forcing along the coastal bluffs. Additionally, the system was designed to function as a prototype monitoring system to evaluate criteria for site selection, instrument selection, and placement of instruments. The purpose of this report is to describe the monitoring system, present the data collected since installation, and describe significant events represented within the dataset, which is published as a separate data release. The findings provide insight for building and configuring larger, modular monitoring networks.

Meteorological data for selected sites along the Colorado River Corridor, Arizona, 2011-13

USGS Publications Warehouse

Caster, Joshua J.; Dealy, Timothy P.; Andrews, Timothy; Fairley, Helen C.; East, Amy E.; Sankey, Joel B.

2014-01-01

This report presents data from 14 automated weather stations collected as part of an ongoing monitoring program within the Grand Canyon National Park and Glen Canyon Recreation Area along the Colorado River Corridor in Arizona. Weather data presented in this document include precipitation, wind speed, maximum wind gusts, wind direction, barometric pressure, relative humidity, and air temperature collected by the Grand Canyon Monitoring and Research Center at 4-minute intervals between January 1, 2011, and December 31, 2013, using automated weather stations consisting of a data logger and a weather transmitter equipped with a piezoelectric sensor, ultrasonic transducers, and capacitive thermal and pressure sensors. Data collection was discontinuous because of station additions, station removals, changes in permits, and equipment failure. A large volume of data was collected for each station. These data are part of a larger research effort focused on physical processes affecting landscapes and archaeological-site stability in the Colorado River Corridor—both natural processes (including meteorological events) and those related to the Glen Canyon Dam operations. Meteorological conditions during the study interval were warmer and drier than is typical, due to ongoing drought conditions during the time period studied. The El Niño/Southern Oscillation was primarily in a neutral state during the reporting period.

Phantosmia as a meteorological forecaster

NASA Astrophysics Data System (ADS)

Aiello, S. R.; Hirsch, A. R.

2013-09-01

In normosmics, olfactory ability has been found to vary with ambient humidity, barometric pressure, and season. While hallucinated sensations of phantom pain associated with changes in weather have been described, a linkage to chemosensory hallucinations has heretofore not been reported. A 64-year-old white male with Parkinson's disease presents with 5 years of phantosmia of a smoky burnt wood which changed to onion-gas and then to a noxious skunk-onion excrement odor. Absent upon waking it increases over the day and persists for hours. When severe, there appears a phantom taste with the same qualities as the odor. It is exacerbated by factors that manipulate intranasal pressure, such as coughing. When eating or sniffing, the actual flavors replace the phantosmia. Since onset, he noted the intensity and frequency of the phantosmia forecasted the weather. Two to 3 h before a storm, the phantosmia intensifies from a level 0 to a 7-10, which persists through the entire thunderstorm. Twenty years prior, he reported the ability to forecast the weather, based on pain in a torn meniscus, which vanished after surgical repair. Extensive olfactory testing demonstrates underlying hyposmia. Possible mechanisms for such chemosensory-meteorological linkage includes: air pressure induced synesthesia, disinhibition of spontaneous olfactory discharge, exacerbation of ectopic discharge, affect mediated somatic sensory amplification, and misattribution error with expectation and recall bias. This is the first reported case of weather-induced exacerbation of phantosmia. Further investigation of the connection between chemosensory complaints and ambient weather is warranted.

Hurricane Balloon Observations in the Hurricane Inflow Layer

NASA Astrophysics Data System (ADS)

Businger, S.; Johnson, R.; Ellis, R.; Talbot, R.

2005-12-01

Four autonomous NOAA smart balloons have been prepared at NOAA's Air Resources Lab Field Research Division. The balloons will be released from the northwest corner of Puerto Rico during August and September 2005 into the inflow of tropical cyclones passing just to the north or south of the island. Ballast control allows the balloons to be positioned low in the atmosphere in the inflow of the storms. Observations will include aspirated temperature and humidity, barometric pressure, GPS position, rain rate, ozone, downward IR temperature, and solar radiation. The observations will be transmitted in real time via satellite cellular telephone and posted to the web. Preliminary results of the analysis of the balloon data sets will be presented, including energy content of the inflow air, estimates of surface fluxes, and evidence of organized eddies. Solar cells will help prolong battery life. If a balloon survives an eye-wall penetration, data on the energy content and ozone concentrations of the boundary layer air in the eye will be presented.

Detecting atmospheric normal modes with periods less than 6 h by barometric observations

NASA Astrophysics Data System (ADS)

Ermolenko, S. I.; Shved, G. M.; Jacobi, Ch.

2018-04-01

The theory of atmospheric normal modes (ANMs) predicts the existence of relatively short-period gravity-inertia ANMs. Simultaneous observations of surface air-pressure variations by barometers at distant stations of the Global Geodynamics Project network during an interval of 6 months were used to detect individual gravity-inertia ANMs with periods of ∼2-5 h. Evidence was found for five ANMs with a lifetime of ∼10 days. The data of the stations, which are close in both latitude and longitude, were utilized for deriving the phases of the detected ANMs. The phases revealed wave propagation to the west and increase of zonal wavenumbers with frequency. As all the detected gravity-inertia ANMs are westward propagating, they are suggested to be generated due to the breakdown of migrating solar tides and/or large-scale Rossby waves. The existence of an ANM background will complicate the detection of the translational motions of the Earth's inner core.

Preseismic Velocity Changes Observed from Active Source Monitoringat the Parkfield SAFOD Drill Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daley, Thomas; Niu, Fenglin; Silver, Paul G.

2008-06-10

Measuring stress changes within seismically active fault zones has been a long-sought goal of seismology. Here we show that such stress changes are measurable by exploiting the stress dependence of seismic wave speed from an active source cross-well experiment conducted at the SAFOD drill site. Over a two-month period we observed an excellent anti-correlation between changes in the time required for an S wave to travel through the rock along a fixed pathway--a few microseconds--and variations in barometric pressure. We also observed two large excursions in the traveltime data that are coincident with two earthquakes that are among those predictedmore » to produce the largest coseismic stress changes at SAFOD. Interestingly, the two excursions started approximately 10 and 2 hours before the events, respectively, suggesting that they may be related to pre-rupture stress induced changes in crack properties, as observed in early laboratory studies.« less

Influence of ambient fungal spores on emergency visits for asthma to a regional children's hospital.

PubMed

Dales, R E; Cakmak, S; Burnett, R T; Judek, S; Coates, F; Brook, J R

2000-12-01

The impact of ambient aeroallergens on morbidity from childhood asthma is largely unknown. To address this issue, we studied the association between daily emergency department visits for asthma to a children's hospital, and daily concentrations of both pollen grains and fungal spores during a 5-yr period between 1993 and 1997. Air pollution and meteorological data accounted for in the analyses included ozone, nitrogen dioxide, sulfur dioxide, sulfates, temperature, barometric pressure, and relative humidity. The daily number of asthma visits ranged from 0 to 36 per day with an average of 7.5. Fungal spores, but not pollen grains, were associated with visits (p < 0.05). The percentage increase associated with each group, independent of the others, was 1.9% (SE 0.9) for deuteromycetes, 4.1% (1.6) for basidiomycetes, 2.8% (1.0) for ascomycetes, and 8.8% for these spores combined. In summary, fungal spores account for a significant proportion of the asthma exacerbations in children that prompt an emergency department visit.

Passenger safety, health, and comfort: a review.

PubMed

Rayman, R B

1997-05-01

Since the birth of aviation medicine approximately 80 yrs ago, practitioners and scientists have given their attention primarily to flight deck crew, cabin crew, and ground support personnel. However, in more recent years we have broadened our horizons to include the safety, health, and comfort of passengers flying commercial aircraft. This will be even more compelling as more passengers take to the air in larger aircraft and flying longer hours to more distant destinations. Further, we can expect to see more older passengers because people in many countries are living longer, healthier lives. The author first discusses the stresses imposed by ordinary commercial flight upon travelers such as airport tumult, barometric pressure changes, immobility, jet lag, noise/ vibration, and radiation. Medical considerations are next addressed describing inflight illness and medical care capability aboard U.S. air carriers. Passenger safety, cabin air quality, and the preventive medicine aspects of air travel are next reviewed in the context of passenger safety, health, and comfort. Recommendations are addressed to regulator agencies, airlines aircraft manufacturers, and the aerospace medicine community.

Fungal spore concentrations in indoor and outdoor air in university libraries, and their variations in response to changes in meteorological variables.

PubMed

Flores, María Elena Báez; Medina, Pável Gaxiola; Camacho, Sylvia Páz Díaz; de Jesús Uribe Beltrán, Magdalena; De la Cruz Otero, María del Carmen; Ramírez, Ignacio Osuna; Hernández, Martín Ernesto Tiznado

2014-08-01

The fungal spore concentration (FSC) in the air poses a risk for human health. This work studied the FSC in university libraries and how it is affected by environmental factors. A total of 347 samples were obtained using a Microbio MB2(®) Aerosol Sampler. The wind speed (WS), cross wind (CW), temperature (T), relative humidity (HR), barometric pressure (BP) and dew point (DP) were recorded using a Kestrel(®) 4500 weather station. The median indoor/outdoor FSC was 360/1230 CFU m(-3). FSC correlated inversely with BP, HR and DP; and positively with WS and CW; whereas T showed negative or positive correlation with FSC, depending on the region or sampling time. Eleven fungal genera were found and the dominant isolates were identified as Aspergillus niger, Aspergillus tamarii and Aspergillus oryzae. All fungi identified are known to be allergenic. It was concluded that environmental variables can influence the air FSC in different ways.

Automated delay measurement system for an Earth station for Two-Way Satellite Time and Frequency Transfer

NASA Technical Reports Server (NTRS)

Dejong, Gerrit; Polderman, Michel C.

1995-01-01

The measurement of the difference of the transmit and receive delays of the signals in a Two-Way Satellite Time and Frequency Transfer (TWSTFT) Earth station is crucial for its nanosecond time transfer capability. Also, the monitoring of the change of this delay difference with time, temperature, humidity, or barometric pressure is important for improving the TWSTFT capabilities. An automated system for this purpose has been developed from the initial design at NMi-VSL. It calibrates separately the transmit and receive delays in cables, amplifiers, upconverters and downconverters, and antenna feeds. The obtained results can be applied as corrections to the TWSTFT measurement when, before and after a measurement session, a calibration session is performed. Preliminary results obtained at NMi-VSL will be shown. Also, if available, the results of a manual version of the system that is planned to be circulated in Sept. 1994 together with a USNO portable station on a calibration trip to European TWSTFT Earth stations.

Taking a 3-D Slice of Hurricane Maria's Cloud Structure

NASA Image and Video Library

2017-09-20

NASA's CloudSat satellite flew over Hurricane Maria on Sept. 17, 2017, at 1:23 p.m. EDT (17:23 UTC) as the storm had just strengthened into a hurricane in the Atlantic Ocean. Hurricane Maria contained estimated maximum sustained winds of 75 miles per hour (65 knots) and had a minimum barometric pressure of 986 millibars. CloudSat flew over Maria through the center of the rapidly intensifying storm, directly through an overshooting cloud top (a dome-shaped protrusion that shoots out of the top of the anvil cloud of a thunderstorm). CloudSat reveals the vertical extent of the overshooting cloud top, showing the estimated height of the cloud to be 11 miles (18 kilometers). Areas of high reflectivity with deep red and pink colors extend well above 9 miles (15 kilometers) in height, showing large amounts of water being drawn upward high into the atmosphere. A movie is available at https://photojournal.jpl.nasa.gov/catalog/PIA21961

Prediction of sub-surface 37 Ar concentrations at locations in the Northwestern United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fritz, Bradley G.; Aalseth, Craig E.; Back, Henning O.

The Comprehensive Nuclear Test-Ban Treaty, which is intended to prevent nuclear weapon testing, includes a verification regime, which provides monitoring to identify potential nuclear testing. The presence of elevated 37Ar is one way to identify subsurface nuclear testing. However, the naturally occurring formation of 37Ar in the subsurface adds a complicating factor. Prediction of the naturally occurring concentration of 37Ar can help to determine if a measured 37Ar concentration is elevated. The naturally occurring 37Ar background concentration has been shown to vary between less than 1 mBq/m3 to greater than 100 mBq/m3 (Riedmann and Purtschert 2011). Here, we evaluate amore » model for predicting the average concentration of 37Ar at any depth under transient barometric pressures, and compare it with measurements. This model is shown to compare favorably with concentrations of 37Ar measured at multiple locations in the Northwestern United States.« less

Field test of the superconducting gravimeter as a hydrologic sensor.

PubMed

Wilson, Clark R; Scanlon, Bridget; Sharp, John; Longuevergne, Laurent; Wu, Hongqiu

2012-01-01

We report on a field test of a transportable version of a superconducting gravimeter (SG) intended for groundwater storage monitoring. The test was conducted over a 6-month period at a site adjacent to a well in the recharge zone of the karstic Edwards Aquifer, a major groundwater resource in central Texas. The purpose of the study was to assess requirements for unattended operation of the SG in a field setting and to obtain a gravimetric estimate of aquifer specific yield. The experiment confirmed successful operation of the SG, but water level changes were small (<0.3 m) leading to uncertainty in the estimate of specific yield. Barometric pressure changes were the dominant cause of both water level variations and non-tidal gravity changes. The specific yield estimate (0.26) is larger than most published values and dependent mainly on low frequency variations in residual gravity and water level time series. © 2011, The Author(s). Ground Water © 2011, National Ground Water Association.

The effect of rapid and sustained decompression on barotrauma in juvenile brook lamprey and Pacific lamprey: implications for passage at hydroelectric facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colotelo, Alison HA; Pflugrath, Brett D.; Brown, Richard S.

Fish passing downstream through hydroelectric facilities may pass through hydroturbines where they experience a rapid decrease in barometric pressure as they pass by turbine blades, which can lead to barotraumas including swim bladder rupture, exopthalmia, emboli, and hemorrhaging. In juvenile Chinook salmon, the main mechanism for injury is thought to be expansion of existing gases (particularly those present in the swim bladder) and the rupture of the swim bladder ultimately leading to exopthalmia, emboli and hemorrhaging. In fish that lack a swim bladder, such as lamprey, the rate and severity of barotraumas due to rapid decompression may be reduced however;more » this has yet to be extensively studied. Another mechanism for barotrauma can be gases coming out of solution and the rate of this occurrence may vary among species. In this study, juvenile brook and Pacific lamprey acclimated to 146.2 kPa (equivalent to a depth of 4.6 m) were subjected to rapid (<1 sec; brook lamprey only) or sustained decompression (17 minutes) to a very low pressure (13.8 kPa) using a protocol previously applied to juvenile Chinook salmon. No mortality or evidence of barotraumas, as indicated by the presence of hemorrhages, emboli or exopthalmia, were observed during rapid or sustained decompression, nor following recovery for up to 120 h following sustained decompression. In contrast, mortality or injury would be expected for 97.5% of juvenile Chinook salmon exposed to a similar rapid decompression to these very low pressures. Additionally, juvenile Chinook salmon experiencing sustained decompression died within 7 minutes, accompanied by emboli in the fins and gills and hemorrhaging in the tissues. Thus, juvenile lamprey may not be susceptible to barotraumas associated with hydroturbine passage to the same degree as juvenile salmonids, and management of these species should be tailored to their specific morphological and physiological characteristics.« less

A Multi-Sensor Fusion MAV State Estimation from Long-Range Stereo, IMU, GPS and Barometric Sensors.

PubMed

Song, Yu; Nuske, Stephen; Scherer, Sebastian

2016-12-22

State estimation is the most critical capability for MAV (Micro-Aerial Vehicle) localization, autonomous obstacle avoidance, robust flight control and 3D environmental mapping. There are three main challenges for MAV state estimation: (1) it can deal with aggressive 6 DOF (Degree Of Freedom) motion; (2) it should be robust to intermittent GPS (Global Positioning System) (even GPS-denied) situations; (3) it should work well both for low- and high-altitude flight. In this paper, we present a state estimation technique by fusing long-range stereo visual odometry, GPS, barometric and IMU (Inertial Measurement Unit) measurements. The new estimation system has two main parts, a stochastic cloning EKF (Extended Kalman Filter) estimator that loosely fuses both absolute state measurements (GPS, barometer) and the relative state measurements (IMU, visual odometry), and is derived and discussed in detail. A long-range stereo visual odometry is proposed for high-altitude MAV odometry calculation by using both multi-view stereo triangulation and a multi-view stereo inverse depth filter. The odometry takes the EKF information (IMU integral) for robust camera pose tracking and image feature matching, and the stereo odometry output serves as the relative measurements for the update of the state estimation. Experimental results on a benchmark dataset and our real flight dataset show the effectiveness of the proposed state estimation system, especially for the aggressive, intermittent GPS and high-altitude MAV flight.

PBO Borehole Strainmeters and Pore Pressure Sensors: Recording Hydrological Strain Signals

NASA Astrophysics Data System (ADS)

Gottlieb, M. H.; Hodgkinson, K. M.; Mencin, D.; Henderson, D. B.; Johnson, W.; Van Boskirk, E.; Pyatt, C.; Mattioli, G. S.

2017-12-01

UNAVCO operates a network of 75 borehole strainmeters along the west coast of the United States and Vancouver Island, Canada as part of the Plate Boundary Observatory (PBO), the geodetic component of the NSF-funded Earthscope program. Borehole strainmeters are designed to detect variations in the strain field at the nanostrain level and can easily detect transient strains caused by aseismic creep events, Episodic Tremor and Slip (ETS) events and seismically induced co- and post-seimic signals. In 2016, one strainmeter was installed in an Oklahoma oil field to characterize in-situ deformation during CO2 injection. Twenty-three strainmeter sites also have pore pressure sensors to measure fluctuations in groundwater pressure. Both the strainmeter network and the pore pressure sensors provide unique data against which those using water-level measurements, GPS time-series or InSAR data can compare possible subsidence signals caused by groundwater withdrawal or fluid re-injection. Operating for 12 years, the PBO strainmeter and pore pressure network provides a long-term, continuous, 1-sps record of deformation. PBO deploys GTSM21 tensor strainmeters from GTSM Technologies, which consist of four horizontal strain gauges stacked vertically, at different orientations, within a single 2 m-long instrument. The strainmeters are typically installed at depths of 200 to 250 m and grouted into the bottom of 15 cm diameter boreholes. The pore pressure sensors are Digiquartz Depth Sensors from Paros Scientific. These sensors are installed in 2" PVC, sampling groundwater through a screened section 15 m above the co-located strainmeter. These sensors are also recording at 1-sps with a resolution in the hundredths of hPa. High-rate local barometric pressure data and low-rate rainfall data also available at all locations. PBO Strainmeter and pore pressure data are available in SEED, SAC-ASCII and time-stamped ASCII format from the IRIS Data Managements Center. Strainmeter data are available at 2-hour latency while the pore pressure data are available in real-time. Links for data access, instrument and borehole information and station histories are available from UNAVCO's Borehole Data web page (https://www.unavco.org/data/strain-seismic/bsm-data/bsm-data.html ).

Thermometers and thermobarometers in granitic systems

USGS Publications Warehouse

Anderson, J.L.; Barth, A.P.; Wooden, J.L.; Mazdab, F.; ,

2008-01-01

The ability to determine the thermal and barometric history during crystallization and emplacement of granitic plutons has been enhanced by several new calibrations applicable to granitic mineral assemblages. Other existing calibrations for granitic plutons have continued to be popular and fairly robust. Recent advances include the trace element thermometers Ti-in-quartz, Ti-in-zircon, and Zr-in-sphene (titanite), which need to be further evaluated on the roles of reduced activities due to lack of a saturating phase, the effect of pressure dependence (particularly for the Ti-in-zircon thermometer), and how resistive these thermometers are to subsolidus reequilibration. As zircon and sphene are also hosts to radiogenic isotopes, these minerals potentially also provide new insights into the temperature - time history of magmas. When used in conjunction with pressure-sensitive mineral equilibria in the same rocks, a complete assessment of the P-T-t (pressure-temperature-time) path is possible given that the mineralogy of plutons can reflect crystallization over a range of pressure and temperature during ascent and emplacement and that many intrusions are now seen as forming over several millions of years during the protracted history of batholith construction. Accessory mineral saturation thermometers, such as those for zircon, apatite, and allanite, provide a different and powerful perspective, specifically that of the temperature of the onset of crystallization of these minerals, which can allow an estimate of the range of temperature between the liquidus and solidus of a given pluton. In assessment of the depth of crystallization and emplacement of granitic plutons, the Al-in-hornblende remains popular for metaluminous granites when appropriately corrected for temperature. For peraluminous granites, potential new calibrations exist for the assemblages bearing garnet, biotite, plagioclase, muscovite, and quartz. Other thermometers, based on oxygen abundance, and including Fe-Ti oxides, pyroxene, fayalitic olivine, quartz, sphene, and/or biotite, some of which have been recently revised, can provide additional information on temperature and oxygen fugacity. Oxygen fugacity can range over several orders of magnitude in different magmatic systems and can have profound influence on the mineralogy and mineral compositions in granitic magmas. It also forms the foundation of the popular magnetite- versus ilmenite-series granite classification. Copyright ?? Mineralogical Society of America.

A measurement of Teide height in 1776

NASA Astrophysics Data System (ADS)

de la Cruz Gallego, María; Vaquero, José M.; García, José A.; Cancillo, María Luisa

1999-09-01

A measurement of the altitude of the Teide peak on Tenerife in the Canary Islands calculated by Spanish and French naval officers from barometric and thermometric data in 1776 is presented here. The observations are described and the result obtained is discussed.

A panel study in congestive heart failure to estimate the short-term effects from personal factors and environmental conditions on oxygen saturation and pulse rate.

PubMed

Goldberg, M S; Giannetti, N; Burnett, R T; Mayo, N E; Valois, M-F; Brophy, J M

2008-10-01

Recent studies suggest that persons with congestive heart failure (CHF) may be at higher risk for short-term effects of air pollution. This daily diary panel study in Montreal, Quebec, was carried out to determine whether oxygen saturation and pulse rate were associated with selected personal factors, weather conditions and air pollution. Thirty-one subjects with CHF participated in this study in 2002 and 2003. Over a 2-month period, the investigators measured their oxygen saturation, pulse rate, weight and temperature each morning and recorded these and other data in a daily diary. Air pollution and weather conditions were obtained from fixed-site monitoring stations. The study made use of mixed regression models, adjusting for within-subject serial correlation and temporal trends, to determine the association between oxygen saturation and pulse rate and personal and environmental variables. Depending on the model, we accounted for the effects of a variety of personal variables (eg, body temperature, salt consumption) as well as nitrogen dioxide (NO2), ozone, maximum temperature and change in barometric pressure at 8:00 from the previous day. In multivariable analyses, the study found that oxygen saturation was reduced when subjects reported that they were ill, consumed salt, or drank liquids on the previous day and had higher body temperatures on the concurrent day (only the latter was statistically significant). Relative humidity and decreased atmospheric pressure from the previous day were associated with oxygen saturation. In univariate analyses, there was negative associations with concentrations of fine particulates, ozone, and sulphur dioxide (SO2), but only SO2 was significant after adjustment for the effects of weather. For pulse rate, no associations were found for the personal variables and in univariate analyses the study found positive associations with NO(2), fine particulates (aerodynamic diameter of 2.5 microm or under, PM(2.5)), SO2, and maximum temperature, although only the latter two were significant after adjustment for environmental effects. The findings from the present investigation suggest that personal and environmental conditions affect intermediate physiological parameters that may affect the health of CHF patients.

[Effect of 2000 m descent simulated in a hyperbaric chamber on arterial blood oxygen saturation and sleep quality in workers of a gold mine situated at an altitude of 3800-4200 m above sea level].

PubMed

Przybyłowski, Tadeusz; Ashirbaev, Aibek; Le Roux, Johannes; Zieliński, Jan

2003-01-01

Acute mountain sickness can become life threatening to people traveling at high altitude. Simulated descent with a hyperbaric chamber is a widely accepted way to treat this condition. The aim of this study was to analyze the influence of simulated descent to 2000 m on arterial oxygen saturation (SaO2), periodic breathing and sleep quality in a group of workers of a gold mine situated at 3800 m. Sleep studies were performed twice in stationary hyperbaric chamber with a portable system--MESAM IV in 20 workers. During the first study the chamber was not pressurized and on the second night the barometric pressure was set to mimic descent to 2000 m. During second study, a significant decrease in ODI (Oxygen Desaturation Index), from 9.7 +/- 6/h to 1.8 +/- 3.4/h (p < 0.0001), was noticed; mean SaO2 increased from 84.3 +/- 3.2% do 92.7 +/- 2.8% (p < 0.0001), significant changes in percentage of study time in individual SaO2 ranges were also noticed. The number (12.7 +/- 8.4 vs. 7.5 +/- 5; p < 0.05) and index of changes in body position were decreased (2.0 +/- 1.5 vs. 1.2 +/- 0.9/h; p < 0.05) as well. Simulated descent to 2000 m causes a decrease in number of desaturations, improvement in mean SaO2 during sleep, decrease in heart rate and these data suggest a decrease in periodic breathing during sleep. A decrease in number and index of body position changes suggests improved sleep quality.

Rugged, Low Cost, Environmental Sensors for a Turbulent World

NASA Astrophysics Data System (ADS)

Schulz, B.; Sandell, C. T.; Wickert, A. D.

2017-12-01

Ongoing scientific research and resource management require a diverse range of high-quality and low-cost sensors to maximize the number and type of measurements that can be obtained. To accomplish this, we have developed a series of diversified sensors for common environmental applications. The TP-DownHole is an ultra-compact temperature and pressure sensor designed for use in CMT (Continuous Multi-channel Tubing) multi-level wells. Its 1 mm water depth resolution, 30 cm altitude resolution, and rugged design make it ideal for both water level measurements and monitoring barometric pressure and associated temperature changes. The TP-DownHole sensor has also been incorporated into a self-contained, fully independent data recorder for extreme and remote environments. This device (the TP-Solo) is based around the TP-DownHole design, but has self-contained power and data storage and is designed to collect data independently for up to 6 months (logging at once an hour), creating a specialized tool for extreme environment data collection. To gather spectral information, we have also developed a very low cost photodiode-based Lux sensor to measure spectral irradiance; while this does not measure the entire solar radiation spectrum, simple modeling to rescale the remainder of the solar spectrum makes this a cost-effective alternative to a thermopile pyranometer. Lastly, we have developed an instrumentation amplifier which is designed to interface a wide range of sensitive instruments to common data logging systems, such as thermopile pyranometers, thermocouples, and many other analog output sensors. These three instruments are the first in a diverse family aimed to give researchers a set of powerful and low-cost tools for environmental instrumentation.

Natural very-low-frequency sferics and headache

NASA Astrophysics Data System (ADS)

Vaitl, D.; Propson, N.; Stark, R.; Schienle, A.

  Very-low-frequency (VLF) atmospherics or sferics are pulse-shaped alternating electric and magnetic fields which originate from atmospheric discharges (lightning). The objective of the study was threefold: (i) to analyse numerous parameters characterizing the sferics activity with regard to their suitability for field studies, (ii) to identify meteorological processes related to the sferics activity and (iii) to investigate the possible association of sferics with pain processes in patients suffering from migraine- and tension-type headaches. Over a period of 6 months (July through December) the sferics activity in the area of Giessen (Germany) was recorded. Three sferics parameters were chosen. The number of sferics impulses per day, the variability of the impulse rate during a day and the variability in comparison to the preceding day were correlated with weather processes (thunderstorm, temperature, vapour pressure, barometric pressure, humidity, wind velocity, warm sector). Significant correlations were obtained during the summer months (July, August) but not during the autumn months (October, November, December). During autumn, however, the sferics activity was correlated with the occurrence of migraine-type headaches (r=0.33, P<0.01) recorded by 37 women who had filled out a headache diary over a period of 6 months (July-December). While the thunderstorm activity was very intense during July and August, no relationship between sferics and migraine was found. In summer, tension-type headaches were associated with meteorological parameters such as temperature (r=0.42, P<0.01) and vapour pressure (r=0.28, P<0.05). Although the sferics activity can explain a small percentage of the variation in migraine occurrence, a direct influence was more likely exerted by visible or otherwise perceptible weather conditions (thunderstorms, humidity, vapour pressure, warm sector, etc.) than by the sferics activity itself.

Simultaneous Measurements of CO2 Concentration and Temperature profiles using 1.6 μm DIAL in the Lower-Atmosphere

NASA Astrophysics Data System (ADS)

Shibata, Y.; Nagasawa, C.; Abo, M.

2016-12-01

High-accurate vertical carbon dioxide (CO2) profiles are highly desirable in the inverse method to improve quantification and understanding of the global sink and source of CO2, and also global climate change. We have developed a ground based 1.6μm differential absorption lidar (DIAL) to achieve measurements of vertical CO2 profiles in the atmosphere. As the spectra of absorption lines of any molecules are influenced basically by the temperature and pressure in the atmosphere, it is important to measure them simultaneously so that the better accuracy of the DIAL measurement is realized. The barometric formula can derive atmospheric pressure of each altitude using atmospheric pressure of ground level at the lidar site. Comparison of atmospheric pressure prlofiles calculated from this equation and those obtained from radiosonde observations at Tateno, Japan are consisted within 0.2 % below 3 km altitude. So, we have developed a 1.6 μm CO2 DIAL system for simultaneous measurements of the CO2 concentration and temperature profiles in the lower-atmosphere. Laser beams of three wavelengths around a CO2 absorption spectrum is transmitted alternately to the atmosphere. Moreover, the value of the retrieved CO2 concentration will be improved remarkably by processing the iteration assignment of CO2 concentration and temperature, which measured by these DIAL techniques. We have acheived vertical CO2 concentration and temperature profile from 0.5 to 2.0 km altitude by this DIAL system. In the next step, we will use this high accuracy CO2 concentration profile and back-trajectory analysis for the behavior analysis of the CO2 mass. This work was financially supported by the System Development Program for Advanced Measurement and Analysis of the Japan Science and Technology Agency.

Protective Effects of Myricetin on Acute Hypoxia-Induced Exercise Intolerance and Mitochondrial Impairments in Rats

PubMed Central

Zou, Dan; Liu, Peng; Chen, Ka; Xie, Qi; Liang, Xinyu; Bai, Qian; Zhou, Qicheng; Liu, Kai; Zhang, Ting; Zhu, Jundong; Mi, Mantian

2015-01-01

Purpose Exercise tolerance is impaired in hypoxia. The aim of this study was to evaluate the effects of myricetin, a dietary flavonoid compound widely found in fruits and vegetables, on acute hypoxia-induced exercise intolerance in vivo and in vitro. Methods Male rats were administered myricetin or vehicle for 7 days and subsequently spent 24 hours at a barometric pressure equivalent to 5000 m. Exercise capacity was then assessed through the run-to-fatigue procedure, and mitochondrial morphology in skeletal muscle cells was observed by transmission electron microscopy (TEM). The enzymatic activities of electron transfer complexes were analyzed using an enzyme-linked immuno-sorbent assay (ELISA). mtDNA was quantified by real-time-PCR. Mitochondrial membrane potential was measured by JC-1 staining. Protein expression was detected through western blotting, immunohistochemistry, and immunofluorescence. Results Myricetin supplementation significantly prevented the decline of run-to-fatigue time of rats in hypoxia, and attenuated acute hypoxia-induced mitochondrial impairment in skeletal muscle cells in vivo and in vitro by maintaining mitochondrial structure, mtDNA content, mitochondrial membrane potential, and activities of the respiratory chain complexes. Further studies showed that myricetin maintained mitochondrial biogenesis in skeletal muscle cells under hypoxic conditions by up-regulating the expressions of mitochondrial biogenesis-related regluators, in addition, AMP-activated protein kinase(AMPK) plays a crucial role in this process. Conclusions Myricetin may have important applications for improving physical performance under hypoxic environment, which may be attributed to the protective effect against mitochondrial impairment by maintaining mitochondrial biogenesis. PMID:25919288

New Madrid Seismic Zone: a test case for naturally induced seismicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nava, S.J.

1983-09-01

Induced seismicity caused by man-made events, such as the filling of reservoirs has been well documented. In contrast, naturally induced seismicity has received little attention. It has been shown that a fluctuation of as little as several bars can trigger reservoir induced earthquakes. Naturally occurring phenomena generate similar fluctuations and could trigger earthquakes where the faults in ambient stress field are suitably oriented and close to failure. The New Madrid Seismic Zone (NMSZ) presents an ideal test case for the study of naturally induced seismicity. The ideal data set for a study of triggering effects must contain a statistically significantmore » number of events, a constant accumulated strain, and a limited focal region. New Madrid earthquakes are well documented from 1974 to the present, down to a magnitude approx. 1.8. They lie in a distinct fault pattern and occur as a reaction to the regional stress regime. A statistical correlation was made between the earthquakes and a variety of different types of loads, to see if New Madrid seismicity could be triggered by natural fluctuations. The types of triggers investigated ranged from solid earth tides to variations in barometric pressure, rainfall, and stages of the Mississippi River. This analysis becomes complex because each factor investigated creates individual stresses, as well as having imbedded in it a reaction to other factors.« less

2007 Weather and Aeolian Sand-Transport Data from the Colorado River Corridor, Grand Canyon, Arizona

USGS Publications Warehouse

Draut, Amy E.; Andrews, Timothy; Fairley, Helen C.; Brown, Christopher R.

2009-01-01

Weather data constitute an integral part of ecosystem monitoring in the Colorado River corridor and are particularly valuable for understanding processes of landscape change that contribute to the stability of archeological sites. Data collected in 2007 are reported from nine weather stations in the Colorado River corridor through Grand Canyon, Ariz. The stations were deployed in February and March 2007 to measure wind speed and direction, rainfall, air temperature, relative humidity, and barometric pressure. Sand traps near each weather station collect windblown sand, from which daily aeolian sand-transport rates are calculated. The data reported here were collected as part of an ongoing study to test and evaluate methods for quantifying processes that affect the physical integrity of archeological sites along the river corridor; as such, these data can be used to identify rainfall events capable of causing gully incision and to predict likely transport pathways for aeolian sand, two landscape processes integral to the preservation of archeological sites. Weather data also have widespread applications to other studies of physical, cultural, and biological resources in Grand Canyon. Aeolian sand-transport data reported here, collected in the year before the March 2008 High-Flow Experiment (HFE) at Glen Canyon Dam, represent baseline data against which the effects of the 2008 HFE on windblown sand will be compared in future reports.

Characteristics of precision 1 Ω standard resistors influencing transport behaviour and the uncertainty of key comparisons

NASA Astrophysics Data System (ADS)

Jones, G. R.; Pritchard, B. J.; Elmquist, R. E.

2009-10-01

National measurement institutes (NMIs) participate in international key comparisons organized by the Bureau International des Poids et Mesures (BIPM), the Regional Metrology Organizations (RMOs) or the Consultative Committees of the Comité International des Poids et Mesures (CIPM) in order to provide evidence of equivalent reference standards and measurement capabilities. The US National Institute of Standards and Technology (NIST) and the National Measurement Institute of Australia (NMIA) have recently examined power loading and several other influences on the value of precision transportable 1 Ω resistors that can increase the uncertainty of key comparisons. We have studied the effects of temperature, barometric pressure, humidity, power loading and heat dissipation in oil on transportable wire-wound 1 Ω resistance standards that are based on different alloys and construction principles. This work focuses on standards manufactured from 1970 through 2000 by the NMIA made of Evanohm alloy and on Thomas-type resistors designed in the 1930s and made of Manganin alloy. We show that the relative standard uncertainty related to transport can be less than 0.01 μΩ Ω-1 when using certain resistors of these two types that are characterized and selected for stability. We describe the characterization process, and relate the environmental influences to the physical design, as well as to the mechanical properties and condition of the standards.

Using in situ vertical displacements to characterize changes in moisture load

NASA Astrophysics Data System (ADS)

Murdoch, Lawrence C.; Freeman, Clay E.; Germanovich, Leonid N.; Thrash, Colby; DeWolf, Scott

2015-08-01

Changes in soil moisture content alter the load on underlying material, and we have developed a technique for characterizing this effect by using an extensometer to measure the displacement caused by the load change. The extensometer is pushed into soil at depths of 5 m or more, and displacement between two anchors separated by ˜1.5 m is measured with a resolution of better than 0.01 μm (10-8 m). The instrument is sensitive to load changes at the ground surface within a radial distance that is roughly twice its depth, potentially providing a method for averaging changes in water content over hundreds of m2 or more. During a field trial at a site in South Carolina, compressive displacements in unsaturated saprolite were strongly correlated to rainfall with a calibration factor of 0.16 μm displacement per mm of rainfall ±0.002 μm/mm (R2 = 0.95). Estimates of the net change in water volume per unit area made using the calibration factor from rainfall were similar to independent estimates of evapotranspiration. The technique was affected by barometric pressure variations, but the sensitivity was less than expected and does not hinder meaningful application. A companion instrument demonstrated the displacement signal was repeatable. This article was corrected on 11 SEP 2015. See the end of the full text for details.

Altitude-related hypoxia: risk assessment and management for passengers on commerical aircraft.

PubMed

Mortazavi, Amir; Eisenberg, Mark J; Langleben, David; Ernst, Pierre; Schiff, Renee L

2003-09-01

Individuals with pulmonary and cardiac disorders are particularly at risk of developing hypoxemia at altitude. Our objective is to describe the normal and maladaptive physiological responses to altitude-related hypoxia, to review existing methods and guidelines for preflight assessment of air travelers, and to provide recommendations for treatment of hypoxia at altitude. Falling partial pressure of oxygen with altitude results in a number of physiologic adaptations including hyperventilation, pulmonary vasoconstriction, altered ventilation/perfusion matching, and increased sympathetic tone. According to three guideline statements, the arterial pressure of oxygen (PaO2) should be maintained above 50 to 55 mm Hg at all altitudes. General indicators such as oxygen saturation and sea level blood gases may be useful in predicting altitude hypoxia. More specialized techniques for estimation of altitude PaO2, such as regression equations, hypoxia challenge testing, and hypobaric chamber exposure have also been examined. A regression equation using sea level PaO2 and spirometric parameters can be used to estimate PaO2 at altitude. Hypoxia challenge testing, performed by exposing subjects to lower inspired FIO2 at sea level may be more precise. Hypobaric chamber exposure, the gold standard, mimics lower barometric pressure, but is mainly used in research. Oxygen supplementation during air travel is needed for individuals with an estimated PaO2 (8000 ft) below 50 mmHg. There are a number of guidelines for the pre-flight assessment of patients with pulmonary and/or cardiac diseases. However, these data are based on small studies in patients with a limited group of diseases.

Triggering and modulation of geyser eruptions in Yellowstone National Park by earthquakes, earth tides, and weather

USGS Publications Warehouse

Hurwitz, Shaul; Sohn, Robert A.; Luttrell, Karen; Manga, Michael

2014-01-01

We analyze intervals between eruptions (IBEs) data acquired between 2001 and 2011 at Daisy and Old Faithful geysers in Yellowstone National Park. We focus our statistical analysis on the response of these geysers to stress perturbations from within the solid earth (earthquakes and earth tides) and from weather (air pressure and temperature, precipitation, and wind). We conclude that (1) the IBEs of these geysers are insensitive to periodic stresses induced by solid earth tides and barometric pressure variations; (2) Daisy (pool geyser) IBEs lengthen by evaporation and heat loss in response to large wind storms and cold air; and (3) Old Faithful (cone geyser) IBEs are not modulated by air temperature and pressure variations, wind, and precipitation, suggesting that the subsurface water column is decoupled from the atmosphere. Dynamic stress changes of 0.1−0.2 MPa resulting from the 2002 M-7.9 Denali, Alaska, earthquake surface waves caused a statistically significant shortening of Daisy geyser's IBEs. Stresses induced by other large global earthquakes during the study period were at least an order of magnitude smaller. In contrast, dynamic stresses of >0.5 MPa from three large regional earthquakes in 1959, 1975, and 1983 caused lengthening of Old Faithful's IBEs. We infer that most subannual geyser IBE variability is dominated by internal processes and interaction with other geysers. The results of this study provide quantitative bounds on the sensitivity of hydrothermal systems to external stress perturbations and have implications for studying the triggering and modulation of volcanic eruptions by external forces.

A Multi-Sensor Fusion MAV State Estimation from Long-Range Stereo, IMU, GPS and Barometric Sensors

PubMed Central

Song, Yu; Nuske, Stephen; Scherer, Sebastian

2016-01-01

State estimation is the most critical capability for MAV (Micro-Aerial Vehicle) localization, autonomous obstacle avoidance, robust flight control and 3D environmental mapping. There are three main challenges for MAV state estimation: (1) it can deal with aggressive 6 DOF (Degree Of Freedom) motion; (2) it should be robust to intermittent GPS (Global Positioning System) (even GPS-denied) situations; (3) it should work well both for low- and high-altitude flight. In this paper, we present a state estimation technique by fusing long-range stereo visual odometry, GPS, barometric and IMU (Inertial Measurement Unit) measurements. The new estimation system has two main parts, a stochastic cloning EKF (Extended Kalman Filter) estimator that loosely fuses both absolute state measurements (GPS, barometer) and the relative state measurements (IMU, visual odometry), and is derived and discussed in detail. A long-range stereo visual odometry is proposed for high-altitude MAV odometry calculation by using both multi-view stereo triangulation and a multi-view stereo inverse depth filter. The odometry takes the EKF information (IMU integral) for robust camera pose tracking and image feature matching, and the stereo odometry output serves as the relative measurements for the update of the state estimation. Experimental results on a benchmark dataset and our real flight dataset show the effectiveness of the proposed state estimation system, especially for the aggressive, intermittent GPS and high-altitude MAV flight. PMID:28025524

Inertial Navigation System Standardized Software Development. Volume 1. Introduction and Summary

DTIC Science & Technology

1976-06-01

the Loran receiver, the Tacan receiver, the Omega receiver, the satelite based instrumentation, the multimode radar, the star tracker and the visual...accelerometer scale factor, and the barometric altimeter bias. The accuracy (1o values) of typical navigation-aid measurements (other than satelite derived

Two boys and a can of coca-cola

NASA Astrophysics Data System (ADS)

Partensky, Michael B.

2002-02-01

A barometric analogy imposes a limit ˜10 meters for a height from which one can sip Coke through a straw from a can placed on the ground. How did Jeff manage to overcome this restriction without using anyone's help or tools? One possible solution is offered.

High Resolution Time Series Cave Ventilation Processes and the Effects on Cave Air Chemistry and Drip Waters: Speleoclimatology and Proxy Calibration

NASA Astrophysics Data System (ADS)

Kowalczk, A. J.; Froelich, P. N.; Gaffka, C.; Tremaine, D.

2008-12-01

Continuous high resolution (sub-hourly), long-term (Nov 2007-present) monitoring of cave air chemistry (Temperature, Relative Humidity, Barometric Pressure, Radon-222, CO2, Air flow, Wind speed and direction) in a shallow subtropical cave (Hollow Ridge) in N Florida reveals two major ventilation mechanisms: 1) ventilation driven by winds across the cave entrances, and 2) ventilation driven by density differences between atmospheric and cave air. The degree and type of ventilation strongly influence the 222Rn and CO2 of cave air, which in turn affects the timing and extent of calcite deposition in speleothems. The degree of ventilation is estimated using a cave air CO2-δ13CO2 Keeling Plot, or a simple radon deficiency model. Results show cave air has an atmospheric component ranging from 10-90%. During fall and winter, average CO2 (700 ppmv) and 222Rn (50-100 dpm/L) are lower than in spring and summer (CO2 = 1200 ppmv; 222Rn = 1000 dpm/L) due to increased winter ventilation. Decreased ventilation during the summer allows CO2 and 222Rn levels to rise. Winter daily ventilation is primarily a function of density gradients between cave air and atmospheric air, while summer daily ventilation is primarily a function of late morning NW-NE winds above the cave. Stable isotope analyses of drip water (fracture drip and pore flow drip) and aquifer water from Hollow Ridge agree with previous isotope studies of drip water at Florida Caverns State Park, 2 km to the NE. During summer, isotopic composition of pore flow drip water (δ18O -3.8 to -4.0 per mil; δD -17.3 to -20.2 per mil VSMOW) and aquifer water (δ18O -4.0 per mil; δD -18.0 to -21.1 per mil) are similar to average annual weighted isotopic composition of precipitation (δ18O -3.6 per mil) while fracture drip waters (δ18O -3 to -3.4 per mil; δD -11.9 to -14.3 per mil) likely reflect the isotopic composition of individual precipitation events. Pore flow drip waters δ18O are weakly correlated with drip rates (enriched δ18O during periods of higher drip rates) but show no correlation to precipitation amount. Knowledge of the type of drip flow is important when considering stalagmites for paleoclimate studies. A significant decrease in drip rate was observed from June (1034 drips/hour) through August 2008 (34 drips/hour). Higher water demands during summer months with increased evapotranspiration may be responsible for this decrease. A semi-diurnal drip rate cycle, negatively correlated with barometric pressure, is also observed throughout the period. This strong negative correlation is hypothesized to be controlled by atmospheric tidal oscillations. Observations into the fall and winter seasons should reveal seasonality, if any, and if there is an evapotranspiration effect present in the water cycle. High resolution studies of cave air chemistry and ventilation processes will enhance knowledge of the timing, extent, and isotopic and chemical composition of calcite deposition. When combined with drip water and precipitation isotope analyses, these studies will improve the understanding and interpretation of high- resolution (sub-annual) speleothem paleoclimate records.

Trend analysis of ground-water levels and spring discharge in the Yucca Mountain Region, Nevada and California, 1960-2000

USGS Publications Warehouse

Fenelon, Joseph M.; Moreo, Michael T.

2002-01-01

Ground-water level and discharge data from 1960 to 2000 were analyzed for the Yucca Mountain region of southern Nevada and eastern California. Included were water-level data from 37 wells and a fissure (Devils Hole) and discharge data from five springs and from a flowing well. Data were evaluated for variability and for upward, downward, or cyclic trends with an emphasis on the period 1992-2000. Potential factors causing trends in water levels and discharge include ground-water withdrawal, infiltration of precipitation, earthquakes, evapotranspiration, barometric pressure, and earth tides. Statistically significant trends in ground-water levels or spring discharge from 1992 to 2000 were upward at 12 water-level sites and downward at 14 water-level sites and 1 spring-discharge site. In general, the magnitude of the change in water level from 1992 to 2000 was small (less than 2 feet), except where influenced by pumping or local effects such as possible equilibration from well construction or diversion of nearby surface water. Seasonal trends are superimposed on some of the long-term (1992-2000) trends in water levels and discharge. Factors causing seasonal trends include barometric pressure, evapotranspiration, and pumping. The magnitude of seasonal change in water level can vary from as little as 0.05 foot in regional aquifers to greater than 5 feet in monitoring wells near large supply wells in the Amargosa Farms area. Three major episodes of earthquake activity affected water levels in wells in the Yucca Mountain region between 1992 and 2000: the Landers/Little Skull Mountain, Northridge, and Hector Mine earthquakes. The Landers/Little Skull Mountain earthquakes, in June 1992, had the largest observed effect on water levels and on discharge during the study period. Monthly measurements of wells in the study network show that earthquakes affected water levels from a few tenths of a foot to 3.5 feet. In the Ash Meadows area, water levels remained relatively stable from 1992 to 2000, with some water levels showing small rising trends and some declining slightly. Possible reasons for water-level fluctuations at sites AD-6 (Tracer Well 3), AM-5 (Devils Hole Well), and AM-4 (Devils Hole) from 1960 to 2000 include climate change, local and regional ground-water withdrawals, and tectonic activity. In Jackass Flats, water levels from 1992 to 2000 in six wells adjacent to Fortymile Wash displayed either small upward trends or no upward or downward trend. Comparison of trends in water levels from 1983 to 2000 for these six wells shows good correlations between all wells and suggests a common mechanism controlling water levels in the area. Of the likely controls on the system--precipitation or pumping in Jackass Flats--precipitation appears to be the predominant factor controlling water levels near Fortymile Wash. Water levels in the heavily pumped Amargosa Farms area declined from about 10 to 30 feet from 1964 to 2000. Water-level declines accelerated beginning in the early 1990's as pumping rates increased substantially. Pumping in the Amargosa Farms area may affect water levels in some wells as far away as 5-14 miles. The water level at site DV-3 (Travertine Point 1 Well) and discharge at site DV-2 (Navel Spring), both in the Death Valley hydrographic area, had downward trends from 1992 to 2000. The cause of these downward trends may be linked to earthquakes, pumping in the Amargosa Farms area, or both.

40 CFR 409.22 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Crystalline Cane Sugar Refining Subcategory § 409.22 Effluent limitations guidelines representing the degree of... crystalline cane sugar refinery discharging both barometric condenser cooling water and other process waters...

40 CFR 409.82 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Puerto Rican Raw Cane Sugar Processing Subcategory § 409.82 Effluent limitations guidelines representing the degree...): (a) Any cane sugar factory continuously discharging both barometric condenser cooling water and other...

40 CFR 409.42 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Louisiana Raw Cane Sugar Processing Subcategory § 409.42 Effluent limitations guidelines representing the degree of... cane sugar factory continuously discharging both barometric condenser cooling water and other process...

40 CFR 409.22 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Crystalline Cane Sugar Refining Subcategory § 409.22 Effluent limitations guidelines representing the degree of... crystalline cane sugar refinery discharging both barometric condenser cooling water and other process waters...

40 CFR 409.82 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Puerto Rican Raw Cane Sugar Processing Subcategory § 409.82 Effluent limitations guidelines representing the degree...): (a) Any cane sugar factory continuously discharging both barometric condenser cooling water and other...

40 CFR 409.42 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Louisiana Raw Cane Sugar Processing Subcategory § 409.42 Effluent limitations guidelines representing the degree of... cane sugar factory continuously discharging both barometric condenser cooling water and other process...

7 CFR 58.217 - Evaporators and/or vacuum pans.

Code of Federal Regulations, 2011 CFR

2011-01-01

....217 Evaporators and/or vacuum pans. Evaporators or vacuum pans or both, with open type condensers shall be equipped with an automatic condenser water level control, barometric leg, or so constructed so... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. When enclosed type condensers...

40 CFR 430.52 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2011 CFR

2011-07-01

... [Bisulfite liquor/surface condensers; BPT effluent limitations for papergrade sulfite facilities where blow... range of 5.0 to 9.0 at all times. Subpart E [Bisulfite liquor/barometric condensers; BPT effluent... [Acid sulfite liquor/surface condensers; BPT effluent limitations for papergrade sulfite facilities...

40 CFR 430.52 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

... [Bisulfite liquor/surface condensers; BPT effluent limitations for papergrade sulfite facilities where blow... range of 5.0 to 9.0 at all times. Subpart E [Bisulfite liquor/barometric condensers; BPT effluent... [Acid sulfite liquor/surface condensers; BPT effluent limitations for papergrade sulfite facilities...

40 CFR 409.82 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2012 CFR

2012-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Puerto Rican Raw Cane Sugar Processing Subcategory § 409.82 Effluent limitations guidelines representing the degree...): (a) Any cane sugar factory continuously discharging both barometric condenser cooling water and other...

40 CFR 409.82 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2014 CFR

2014-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Puerto Rican Raw Cane Sugar Processing Subcategory § 409.82 Effluent limitations guidelines representing the degree...): (a) Any cane sugar factory continuously discharging both barometric condenser cooling water and other...

40 CFR 409.82 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Puerto Rican Raw Cane Sugar Processing Subcategory § 409.82 Effluent limitations guidelines representing the degree...): (a) Any cane sugar factory continuously discharging both barometric condenser cooling water and other...

40 CFR 409.22 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2012 CFR

2012-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Crystalline Cane Sugar Refining Subcategory § 409.22 Effluent limitations guidelines representing the degree of... crystalline cane sugar refinery discharging both barometric condenser cooling water and other process waters...

40 CFR 409.22 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Crystalline Cane Sugar Refining Subcategory § 409.22 Effluent limitations guidelines representing the degree of... crystalline cane sugar refinery discharging both barometric condenser cooling water and other process waters...

40 CFR 409.22 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2014 CFR

2014-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Crystalline Cane Sugar Refining Subcategory § 409.22 Effluent limitations guidelines representing the degree of... crystalline cane sugar refinery discharging both barometric condenser cooling water and other process waters...

40 CFR 409.42 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Louisiana Raw Cane Sugar Processing Subcategory § 409.42 Effluent limitations guidelines representing the degree of... cane sugar factory continuously discharging both barometric condenser cooling water and other process...

40 CFR 409.42 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2012 CFR

2012-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Louisiana Raw Cane Sugar Processing Subcategory § 409.42 Effluent limitations guidelines representing the degree of... cane sugar factory continuously discharging both barometric condenser cooling water and other process...

40 CFR 409.42 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2014 CFR

2014-07-01

... AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Louisiana Raw Cane Sugar Processing Subcategory § 409.42 Effluent limitations guidelines representing the degree of... cane sugar factory continuously discharging both barometric condenser cooling water and other process...

Field Observations of Meteotsunami in Kami-koshiki Island, Japan

NASA Astrophysics Data System (ADS)

Asano, T.; Yamashiro, T.; Nishimura, N.

2012-12-01

BACKGROUND Meteotsunami; atmospherically induced destructive ocean waves in the tsunami frequency band, are known in Japan by the local term "abiki", literally meaning "net-dragging waves" in Japanese. Large abiki occur in bays and harbors along the west coast of Kyushu almost every year during winter and early spring. On 24-25 February, 2009, Urauchi Bay, located on west coast of Kami-Koshiki Island on the southeast coast of Kyushu, was subjected to a destructive meteotsunami. In this event, a maximum sea surface height of 3.1 m was observed at the inner part of the bay. At least 18 boats capsized and eight houses were flooded. This event surpassed the previous record height for an abiki in Japan: 278 cm in Nagasaki Bay, also located west coast of Kyushu, in 1979. Generally, such an elongated inlet with narrow mouth as Urauchi bay provides calm water conditions even when offshore weather is stormy. Therefore, the area is regarded as a suitable place for the farming of large fish with a high market value. Possible damage to the extensive fish cage system as a result of meteotsunami events is of concern, especially because aquaculture is the main industry in the isolated islands. Forecasting of meteotsunami is a serious request from the local people. AIMS The objectives of the present study are to detect a meteotsunami event in Urauchi Bay and to clarify the meteorological and hydrodynamic conditions related to its occurrence. This work attempts to observe the whole process of a meteotsunami event: generation offshore, resonance while it propagates, and finally amplification in the bay. Observations were conducted over a period of 82 days; 12 January to 4 April, 2010, aiming to record large secondary oscillations. A comprehensive measuring system for sea level, current and barometric pressure fluctuations was deployed covering not only inside and near Urauchi Bay but also further offshore in the vicinity of Mejima in the East China Sea. MAIN RESULTS 1) Large meteotsunami events with total height in excess of 150 cm were observed five times during the 82-day observation period. On 1 February, 2010, one such event coincided with the high water of a spring tide, which resulted in flooding. The present observations have revealed that meteotsunami events occur more frequently than previously estimated from existing records of flooding. Even if a meteotsunami event does not result in flooding (e.g., if it coincides with a low tide), attention should be paid to the seiche induced strong currents that may damage fishing boats or aquaculture installations. 2) Three dominant modes were found to exist in sea level fluctuation data in Urauchi Bay using spectra analysis, wavelet analysis and phase analysis of the extracted period band components. The node and anti-node structure for each node governs more energetic areas for sea level and the current velocity fluctuations. 3) Analyses of barometric pressure data show that abrupt pressure changes of 1-2 hPa are generated in the open sea area at Mejima when major meteotsunami events occur. The pressure waves propagated eastward or northeastward to reach Kami-Koshiki within 1-2 hours. The propagation speed was found to nearly coincide with ocean long waves over the East China Sea. This air-sea resonant coupling is considered to be a source mechanism of meteotsunami generation.

Yosemite Hydroclimate Network: Distributed stream and atmospheric data for the Tuolumne River watershed and surroundings

NASA Astrophysics Data System (ADS)

Lundquist, Jessica D.; Roche, James W.; Forrester, Harrison; Moore, Courtney; Keenan, Eric; Perry, Gwyneth; Cristea, Nicoleta; Henn, Brian; Lapo, Karl; McGurk, Bruce; Cayan, Daniel R.; Dettinger, Michael D.

2016-09-01

Regions of complex topography and remote wilderness terrain have spatially varying patterns of temperature and streamflow, but due to inherent difficulties of access, are often very poorly sampled. Here we present a data set of distributed stream stage, streamflow, stream temperature, barometric pressure, and air temperature from the Tuolumne River Watershed in Yosemite National Park, Sierra Nevada, California, USA, for water years 2002-2015, as well as a quality-controlled hourly meteorological forcing time series for use in hydrologic modeling. We also provide snow data and daily inflow to the Hetch Hetchy Reservoir for 1970-2015. This paper describes data collected using low-visibility and low-impact installations for wilderness locations and can be used alone or as a critical supplement to ancillary data sets collected by cooperating agencies, referenced herein. This data set provides a unique opportunity to understand spatial patterns and scaling of hydroclimatic processes in complex terrain and can be used to evaluate downscaling techniques or distributed modeling. The paper also provides an example methodology and lessons learned in conducting hydroclimatic monitoring in remote wilderness.

Climatology at the Roque de LOS Muchachos Observatory

NASA Astrophysics Data System (ADS)

Varela, Antonia M.; Muñoz-Tuñón, Casiana

2009-09-01

The Roque de los Muchachos Observatory (ORM) at La Palma (Canary Islands) is one of the two top pre-selected sites for hosting the future European Extremely Large Telescope (E-ELT), the other ones are Ventarrones (Chile), Macon (Argentine) and Aklim (Maroc). Meteorological and seeing conditions are crucial both for the site selection and for telescope design and feasibility studies for adaptive optics. The ELTs shall be very sensitive to wind behavior when operating in open air, therefore ground level wind velocity and wind gust are also required for the feasibility of the telescope construction. Here we analyze the wind speed and wind direction, the air temperature, the relative humidity and the barometric pressure statistical results obtained from data recorded at different sites at the ORM by several Automatic Weather Stations (AWS) since 1985, day and night time separately. Ground wind speed regimes (775mbar) are compared with those provided by satellites from 200 to 700mbar. There exists also observational evidence of the correlation between the seeing and the wind speed and wind direction that will be discussed in this work.

Metallurgical Laboratory (MetLab) Treatability Study: An Analysis of Passive Soil Vapor Extraction Wells (PSVE) FY1999 Update

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riha, B.D.

1999-10-20

The results to date on the treatability study of the PSVE system at the MetLab of the Savannah River Site (SRS) indicate the technology is performing well. Well concentrations are decreasing and contour maps of the vadose zone soil gas plume show a decrease in the extent of the plume. In the 18 months of operation approximately 200 pounds of chlorinated organic contaminants have been removed by natural barometric pumping of wells fitted with BaroBall valves (low pressure check valves). The mass removal estimates are approximate since the flow rates are estimated, the concentration data is based on exponential fitsmore » of a limited data set, and the concentration data is normalized to the average CO2.The concentration values presented in this report should be taken as the general trend or order of magnitude of concentration until longer-term data is collected. These trends are of exponentially decreasing concentration showing the same characteristics as the concentration trends at the SRS Miscellaneous Chemical Basin after three years of PSVE (Riha et. al., 1999).« less

Atmospheric mold spore counts in relation to meteorological parameters

NASA Astrophysics Data System (ADS)

Katial, R. K.; Zhang, Yiming; Jones, Richard H.; Dyer, Philip D.

Fungal spore counts of Cladosporium, Alternaria, and Epicoccum were studied during 8 years in Denver, Colorado. Fungal spore counts were obtained daily during the pollinating season by a Rotorod sampler. Weather data were obtained from the National Climatic Data Center. Daily averages of temperature, relative humidity, daily precipitation, barometric pressure, and wind speed were studied. A time series analysis was performed on the data to mathematically model the spore counts in relation to weather parameters. Using SAS PROC ARIMA software, a regression analysis was performed, regressing the spore counts on the weather variables assuming an autoregressive moving average (ARMA) error structure. Cladosporium was found to be positively correlated (P<0.02) with average daily temperature, relative humidity, and negatively correlated with precipitation. Alternaria and Epicoccum did not show increased predictability with weather variables. A mathematical model was derived for Cladosporium spore counts using the annual seasonal cycle and significant weather variables. The model for Alternaria and Epicoccum incorporated the annual seasonal cycle. Fungal spore counts can be modeled by time series analysis and related to meteorological parameters controlling for seasonallity; this modeling can provide estimates of exposure to fungal aeroallergens.

Radon anomaly in soil gas as an earthquake precursor.

PubMed

Miklavcić, I; Radolić, V; Vuković, B; Poje, M; Varga, M; Stanić, D; Planinić, J

2008-10-01

The mechanical processes of earthquake preparation are always accompanied by deformations; afterwards, the complex short- or long-term precursory phenomena can appear. Anomalies of radon concentrations in soil gas are registered a few weeks or months before many earthquakes. Radon concentrations in soil gas were continuously measured by the LR-115 nuclear track detectors at site A (Osijek) during a 4-year period, as well as by the Barasol semiconductor detector at site B (Kasina) during 2 years. We investigated the influence of the meteorological parameters on the temporal radon variations, and we determined the equation of the multiple regression that enabled the reduction (deconvolution) of the radon variation caused by the barometric pressure, rainfall and temperature. The pre-earthquake radon anomalies at site A indicated 46% of the seismic events, on criterion M>or=3, R<200 km, and 21% at site B. Empirical equations between earthquake magnitude, epicenter distance and precursor time enabled estimation or prediction of an earthquake that will rise at the epicenter distance R from the monitoring site in expecting precursor time T.

Using the ENTLN lightning catalog to identify thunder signals in the USArray Transportable Array

NASA Astrophysics Data System (ADS)

Tytell, J. E.; Reyes, J. C.; Vernon, F.; Sloop, C.; Heckman, S.

2013-12-01

Severe weather events can pose a challenge for seismic analysts who regularly see non-seismic signals recorded at the stations. Sometimes, the noise from thunder can be confused with signals from seismic events such as quarry blasts or earthquakes depending on where and when the noise is observed. Automatic analysis of data is also severely affected by big amplitude arrivals that we could safely ignore. A comprehensive lightning catalog for the continental US in conjunction with a travel time model for thunder arrivals can help analysts identify some of these unknown sources. Researchers from Earthscope's USArray Transportable Array (TA) have partnered with the Earth Networks Total Lightning Network (ENTLN) in an effort to create such a catalog. Predicted thunder arrivals from some powerful meteorological systems affecting the main TA footprint will undergo extensive evaluation. We will examine the veracity of the predicted arrivals at different distances and azimuths and the time accuracy of the model. A combination of barometric pressure and seismic signals will be use to verify these arrivals.

Yosemite Hydroclimate Network: Distributed stream and atmospheric data for the Tuolumne River watershed and surroundings

USGS Publications Warehouse

Lundquist, Jessica D.; Roche, James W.; Forrester, Harrison; Moore, Courtney; Keenan, Eric; Perry, Gwyneth; Cristea, Nicoleta; Henn, Brian; Lapo, Karl; McGurk, Bruce; Cayan, Daniel R.; Dettinger, Michael D.

2016-01-01

Regions of complex topography and remote wilderness terrain have spatially varying patterns of temperature and streamflow, but due to inherent difficulties of access, are often very poorly sampled. Here we present a data set of distributed stream stage, streamflow, stream temperature, barometric pressure, and air temperature from the Tuolumne River Watershed in Yosemite National Park, Sierra Nevada, California, USA, for water years 2002–2015, as well as a quality-controlled hourly meteorological forcing time series for use in hydrologic modeling. We also provide snow data and daily inflow to the Hetch Hetchy Reservoir for 1970–2015. This paper describes data collected using low-visibility and low-impact installations for wilderness locations and can be used alone or as a critical supplement to ancillary data sets collected by cooperating agencies, referenced herein. This data set provides a unique opportunity to understand spatial patterns and scaling of hydroclimatic processes in complex terrain and can be used to evaluate downscaling techniques or distributed modeling. The paper also provides an example methodology and lessons learned in conducting hydroclimatic monitoring in remote wilderness.

Air Deployable Underwater Glider and Buoy Development for Arctic and Oceanographic Sensing

NASA Astrophysics Data System (ADS)

Legnos, P. J.

2013-12-01

LBI developed under a NOAA SBIR the AXIB (Airborne eXpendable Ice Buoy). The initial buoy was developed to collect barometric pressure, air temperature two meters above the surface and sea surface or ice temperature. A number of these AXIBs have been successfully deployed in the Arctic and Antarctic. Currently we are in the process of integrating additional sensors to include an anemometer, thermistor chain and hydrophones. Further development is in process for the integration of solar and wind recharging systems and lower power sensors and processing LBI developed under an ONR SBIR Grant two Air Deployable Underwater Gliders. They are primarily designed for air deployment from Navy P-3 or P-8 Aircraft though easily deployed from other aircraft or helicopters. The A-size (4 7/8'dia. X 36' long) and the 12 ¾ (12 ¾' dia. X 9' 9' long). On the development side we are in the process of integrating sensors and enhancing the battery storage capacity. We anticipate a broad range of Oceanographic sensing missions for these Gliders.

Water-quality data for the Russian River Basin, Mendocino and Sonoma Counties, California, 2005-2010

USGS Publications Warehouse

Anders, Robert; Davidek, Karl; Stoeckel, Donald M.

2011-01-01

Field measurements included discharge, barometric pressure, dissolved oxygen, pH, specific conductance, temperature, and turbidity. All samples were analyzed for nutrients, major ions, trace metals, total and dissolved organic carbon, organic wastewater compounds, standard bacterial indicators, and the stable isotopes of hydrogen and oxygen. Standard bacterial indicators included total coliform, Escherichia coli, enterococci, and Clostridium perfringens for the period 2005 through 2007, and total and fecal coliform, and enterococci for 2010. In addition, enrichment of enterococci was performed on all surface-water samples collected during summer 2006, for detection of the human-associated enterococcal surface protein in Enterococcus faecium to assess the presence of sewage effluent in the Russian River. Other analyses included organic wastewater compounds of bed sediment samples collected from four Russian River sites during 2005; carbon-13 isotopic values of the dissolved inorganic carbon for surface-water and groundwater samples collected during 2006; human-use pharmaceuticals on Russian River samples collected during 2007 and 2010; and the radiogenic isotopes tritium and carbon-14 for groundwater samples collected during 2008.

NREL National Wind Technology Center (NWTC): M2 Tower; Boulder, Colorado (Data)

DOE Data Explorer

Jager, D.; Andreas, A.

1996-09-24

The National Wind Technology Center (NWTC), located at the foot of the Rocky Mountains near Boulder, Colorado, is a world-class research facility managed by NREL for the U.S. Department of Energy. NWTC researchers work with members of the wind energy industry to advance wind power technologies that lower the cost of wind energy through research and development of state-of-the-art wind turbine designs. NREL's Measurement and Instrument Data Center provides data from NWTC's M2 tower which are derived from instruments mounted on or near an 82 meter (270 foot) meteorological tower located at the western edge of the NWTC site and about 11 km (7 miles) west of Broomfield, and approximately 8 km (5 miles) south of Boulder, Colorado. The data represent the mean value of readings taken every two seconds and averaged over one minute. The wind speed and direction are measured at six heights on the tower and air temperature is measured at three heights. The dew point temperature, relative humidity, barometric pressure, totalized liquid precipitation, and global solar radiation are also available.

Temperature deviation index and elderly mortality in Japan.

PubMed

Lim, Youn-Hee; Reid, Colleen E; Honda, Yasushi; Kim, Ho

2016-07-01

Few studies have examined how the precedence of abnormal temperatures in previous neighboring years affects the population's health. In the present study, we attempted to quantify the health effects of abnormal weather patterns by creating a metric called the temperature deviation index (TDI) and estimated the effects of TDI on mortality in Japan. We used data from 47 prefectures in Japan to compute the TDI on days between May and September from 1966 to 2010. The TDI is a summed product of an indicator of absence of high temperatures in the neighboring years, and more weights were assigned to the years closest to the current year. To estimate the TDI effects on elderly mortality, we used generalized linear modeling with a Poisson distribution after adjusting for apparent temperature, barometric pressure, day of the week, and time trend. For each prefecture, we estimated the TDI effects and pooled the estimates to yield a national average for 1991-2010 in Japan. The estimated effects of TDI in middle- or high-latitude prefectures were greater than in low-latitude prefectures. The estimated national average of TDI effects was a 0.5 % (95 % confidence intervals [CI], 0.1, 1.0) increase in elderly mortality per 1-unit (around 1 standard deviation) increase in the TDI. The significant pooled estimation of TDI effects was mainly due to the TDI effects on summer days with moderate temperature (25th-49th percentile, mean temperature 22.9 °C): a 1.9 % (95 % CI, 1.1, 2.6) increase in elderly mortality per 1-unit increase in the TDI. However, TDI effects were insignificant in other temperature ranges. These findings suggest that elderly deaths increased on moderate temperature days in the summer that differed substantially from days during that time window in the neighboring years. Therefore, not only high temperature itself but also temperature deviation compared to previous years could be considered to be a risk factor for elderly mortality in the summer.

Movement, home range, and site fidelity of bluegills in a Great Plains Lake

USGS Publications Warehouse

Paukert, C.P.; Willis, D.W.; Bouchard, M.A.

2004-01-01

Little is known about the distribution, movement, and home ranges of bluegills Lepomis macrochirus in lentic environments. Therefore, the objectives of this study were to evaluate the seasonal and diel differences in movement rates, site fidelity, and home range of bluegills in a shallow, natural Great Plains lake. A total of 78 bluegills (200-273 mm total length) were implanted with radio transmitters in March and May 2000. Of these fish, 10 males and 10 females were randomly selected and located every 2 h during one 24-h period each month from April to September 2000. Bluegill movement peaked during midsummer: however, there was little difference in diel movements, suggesting relatively consistent movement throughout the 24-h period. Home range estimates (which included the 24-h tracking plus an additional six locations from the same fish located once per day for six consecutive days each month) ranged up to 172 ha, probably because only about half of the bluegills exhibited site fidelity during any month sampled. Bluegill movement did not appear to be strongly linked with water temperature, barometric pressure, or wind speed. These results suggest that bluegills move considerable distances and that many roam throughout this 332-ha shallow lake. However, diel patterns were not evident. Sampling bluegills in Great Plains lakes using passive gears (e.g., trap nets) may be most effective during the summer months, when fish are most active. Active sampling (e.g., electrofishing) may be more effective than the use of passive gears in spring and fall, when bluegills are less active.

Effect of fasting during the month of Ramadan on serum levels of luteinizing hormone and testosterone in people living in the below sea level environment in the Jordan Valley.

PubMed

El-Migdadi, Fayig; Shotar, Ali; El-Akawi, Zeyad; Banihani, Ibrahim; Abudheese, Rola

2004-01-01

To study a possible effect of Ramadan fasting on luteinizing hormone and testosterone in people of the Jordan Valley. A comparative study (n=40) of serum levels of luteinizing hormone (LH) and testosterone (T) between people living in the Jordan Valley (JV), n=20, 360 meters below sea level, and those living in Ramtha City (RC), n=20, 600 meters above sea level, was conducted in December, 1998. A similar study (n=40) was also done during January 1999 in fasting people during the month of Ramadan. Serum levels of LH in non-fasting people of the JV were statistically similar to those in people of RC. There was also no difference in serum levels of T between non-fasting people of the JV and those in RC. Serum levels of LH in fasting people of the JV were statistically indifferent from those fasting in RC. Serum T levels in fasting people of the JV, on the other hand, were higher than those in fasting people of RC (76+/-18.3 ng/ml compared to 62.7+/-24.2 ng/ml). It is probably the environmental factors such as the higher barometric pressure of the JV compared to that at above sea level that play a role in higher serum levels of T in people of the JV. Other factors, such as genetic background and/or the cultural and nutritional characteristics of the people of the JV, may also contribute to this difference in serum T levels.

Subsurface Xenon Migration by Atmospheric Pumping Using an Implicit Non-Iterative Algorithm for a Locally 1D Dual-Porosity Model

NASA Astrophysics Data System (ADS)

Annewandter, R.; Kalinowksi, M. B.

2009-04-01

An underground nuclear explosion injects radionuclids in the surrounding host rock creating an initial radionuclid distribution. In the case of fractured permeable media, cyclical changes in atmospheric pressure can draw gaseous species upwards to the surface, establishing a ratcheting pump effect. The resulting advective transport is orders of magnitude more significant than transport by molecular diffusion. In the 1990s the US Department of Energy funded the socalled Non-Proliferation Experiment conducted by the Lawrence Livermore National Laboratory to investigate this barometric pumping effect for verifying compliance with respect to the Comprehensive Nuclear Test Ban Treaty. A chemical explosive of approximately 1 kt TNT-equivalent has been detonated in a cavity located 390 m deep in the Rainier Mesa (Nevada Test Site) in which two tracer gases were emplaced. Within this experiment SF6 was first detected in soil gas samples taken near fault zones after 50 days and 3He after 325 days. For this paper a locally one-dimensional dual-porosity model for flow along the fracture and within the permeable matrix was used after Nilson and Lie (1990). Seepage of gases and diffusion of tracers between fracture and matrix are accounted. The advective flow along the fracture and within the matrix block is based on the FRAM filtering remedy and methodology of Chapman. The resulting system of equations is solved by an implicit non-iterative algorithm. Results on time of arrival and subsurface concentration levels for the CTBT-relevant xenons will be presented.

2008 Weather and Aeolian Sand-Transport Data from the Colorado River Corridor, Grand Canyon, Arizona

USGS Publications Warehouse

Draut, Amy E.; Sondossi, Hoda A.; Hazel, Joseph E.; Andrews, Timothy; Fairley, Helen C.; Brown, Christopher R.; Vanaman, Karen M.

2009-01-01

This report presents measurements of weather parameters and aeolian (windblown) sand transport made in 2008 near selected archaeological sites in the Colorado River corridor through Grand Canyon, Ariz. The quantitative methods and data discussed here form a basis for monitoring ecosystem processes that affect archeological-site stability. Combined with forthcoming work to evaluate landscape evolution at nearby archaeological sites, these data can be used to document the relationship between physical processes, including weather and aeolian sand transport, and their effects on the physical integrity of archaeological sites. Data collected in 2008 reveal event- and seasonal-scale variations in rainfall, wind, temperature, humidity, and barometric pressure. Broad seasonal changes in aeolian sediment flux are also apparent at most study sites. The continuation of monitoring that began in 2007, and installation of equipment at several new sites in early 2008, allowed evaluation of the effects of the March 2008 high-flow experiment (HFE) on aeolian sand transport. At two of the nine sites studied, spring and summer winds reworked 2008 HFE sandbars to form new aeolian dunes, at which sand moved inland toward larger, well-established dune fields. At the other seven study sites, neither dune formation nor enhanced sand transport after the HFE were observed. At several of those sites, dominant wind directions in spring 2008 were not oriented such that much HFE sand would have moved inland; at other sites, lack of increased inland sand flux is attributable to lack of sandbar enlargement near the study sites or to inhibition of sand movement by vegetation or local topography.

Effects of weather conditions on emergency ambulance calls for acute coronary syndromes

NASA Astrophysics Data System (ADS)

Vencloviene, Jone; Babarskiene, Ruta; Dobozinskas, Paulius; Siurkaite, Viktorija

2015-08-01

The aim of this study was to evaluate the relationship between weather conditions and daily emergency ambulance calls for acute coronary syndromes (ACS). The study included data on 3631 patients who called the ambulance for chest pain and were admitted to the department of cardiology as patients with ACS. We investigated the effect of daily air temperature ( T), barometric pressure (BP), relative humidity, and wind speed (WS) to detect the risk areas for low and high daily volume (DV) of emergency calls. We used the classification and regression tree method as well as cluster analysis. The clusters were created by applying the k-means cluster algorithm using the standardized daily weather variables. The analysis was performed separately during cold (October-April) and warm (May-September) seasons. During the cold period, the greatest DV was observed on days of low T during the 3-day sequence, on cold and windy days, and on days of low BP and high WS during the 3-day sequence; low DV was associated with high BP and decreased WS on the previous day. During June-September, a lower DV was associated with low BP, windless days, and high BP and low WS during the 3-day sequence. During the warm period, the greatest DV was associated with increased BP and changing WS during the 3-day sequence. These results suggest that daily T, BP, and WS on the day of the ambulance call and on the two previous days may be prognostic variables for the risk of ACS.

Gauging climate change effects at local scales: weather-based indices to monitor insect harassment in caribou.

PubMed

Witter, Leslie A; Johnson, Chris J; Croft, Bruno; Gunn, Anne; Poirier, Lisa M

2012-09-01

Climate change is occurring at an accelerated rate in the Arctic. Insect harassment may be an important link between increased summer temperature and reduced body condition in caribou and reindeer (both Rangifer tarandus). To examine the effects of climate change at a scale relevant to Rangifer herds, we developed monitoring indices using weather to predict activity of parasitic insects across the central Arctic. During 2007-2009, we recorded weather conditions and used carbon dioxide baited traps to monitor activity of mosquitoes (Culicidae), black flies (Simuliidae), and oestrid flies (Oestridae) on the post-calving and summer range of the Bathurst barren-ground caribou (Rangifer tarandus groenlandicus) herd in Northwest Territories and Nunavut, Canada. We developed statistical models representing hypotheses about effects of weather, habitat, location, and temporal variables on insect activity. We used multinomial logistic regression to model mosquito and black fly activity, and logistic regression to model oestrid fly presence. We used information theory to select models to predict activity levels of insects. Using historical weather data, we used hindcasting to develop a chronology of insect activity on the Bathurst range from 1957 to 2008. Oestrid presence and mosquito and black fly activity levels were explained by temperature. Wind speed, light intensity, barometric pressure, relative humidity, vegetation, topography, location, time of day, and growing degree-days also affected mosquito and black fly levels. High predictive ability of all models justified the use of weather to index insect activity. Retrospective analyses indicated conditions favoring mosquito activity declined since the late 1950s, while predicted black fly and oestrid activity increased. Our indices can be used as monitoring tools to gauge potential changes in insect harassment due to climate change at scales relevant to caribou herds.

Breast Cancer-Related Arm Lymphedema: Fluctuation over Six Months and the Effect of the Weather.

PubMed

Czerniec, Sharon A; Ward, Leigh C; Kilbreath, Sharon L

2016-09-01

An understanding of normal fluctuation of lymphedema over time is important to identify real change, whether it is from response to treatment or worsening of the condition. The weather is another factor that possibly influences lymphedema but has had minimal investigation to date. The purpose of this study was to determine the extent to which breast cancer-related lymphedema (BCRL) fluctuated over a 6-month period and the influence of temperature, humidity, and barometric pressure. Women with unilateral BCRL (n = 26) and without BCRL (n = 17) were measured on nine occasions over 6 months using a standardized protocol. Measures included self-reported arm swelling, arm volume, and extracellular fluid with bioimpedance. Daily weather data were obtained for analysis of effects on lymphedema. Neither arm volume nor extracellular fluid varied significantly for women with lymphedema; coefficients of variation were 2.3% and 3.7%, respectively. Women without lymphedema had even less fluctuation, with coefficient of variation of 1.9% for arm volume and 2.9% for ECF. Correlation of weather and lymphedema data showed that temperature was the only aspect of the weather to have any effect on BCRL, with the maximum temperature on the day before measurement slightly affecting ECF (r = 0.27, p < 0.001), arm volume (r = 0.23, p < 0.001), and self-reported swelling (r = 0.26, p < 0.001). For women without lymphedema, the weather did not affect any measure. Established BCRL is relatively stable over a 6-month period. Temperature was the only aspect of the weather found to impact lymphedema.

The Effect of Borehole Flow on Salinity Profiles From Deep Monitor Wells in Hawaii

NASA Astrophysics Data System (ADS)

Rotzoll, K.; Hunt, C. D.; El-Kadi, A. I.

2008-12-01

Ground-water resource management in Hawaii is based partly on salinity profiles from deep wells that are used to monitor the thickness of freshwater lenses and the transition zone between freshwater and saltwater. Vertical borehole flow in these wells may confound understanding of the actual salinity-depth profiles in the basaltic aquifers and lead to misinterpretations that hamper effective water-resource management. Causes and effects of borehole flow on salinity profiles are being evaluated at 40 deep monitor wells in Hawaii. Step- like changes in fluid electrical conductivity with respect to depth are indicative of borehole flow and are evident in almost all available salinity profiles. A regional trend in borehole flow direction, expected from basin-wide ground-water flow dynamics, is evident as major downward flow components in inland recharge areas and major upward flow components in discharge areas near the coast. The midpoint of the transition zone in one deep monitor well showed inconsequential depth displacements in response to barometric pressure and tidal fluctuations and to pumping from nearby wellfields. Commonly, the 1 mS/cm conductivity value is used to indicate the top of the transition zone. Contrary to the more stable midpoint, the depth of the 1 mS/cm conductivity value may be displaced by as much as 200 m in deep monitor wells near pumping wellfields. The displacement is complemented with an increase in conductivity at a particular depth in the upper part of the profile. The observed increase in conductivity is linear with increase in nearby pumpage. The largest deviations from expected aquifer-salinity profiles occur in deep monitor wells located in the area extending from east Pearl Harbor to Kalihi on Oahu, which coincides with the most heavily pumped part of the aquifer.

40 CFR 409.13 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Beet Sugar Processing... a point source where the sugar beet processing capacity of the point source does not exceed 1090 kkg... results, in whole or in part, from barometric condensing operations and any other beet sugar processing...

40 CFR 409.13 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Beet Sugar Processing... a point source where the sugar beet processing capacity of the point source does not exceed 1090 kkg... results, in whole or in part, from barometric condensing operations and any other beet sugar processing...

40 CFR 86.082-2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., fully enclosing the driver compartment and load carrying device, and having no body sections protruding... the requirements of engine starting. Diurnal breathing losses means evaporative emissions as a result... barometric test conditions of 83.3 kPa (24.2 inches Hg), plus or minus 1 kPa (0.30 Hg). Hot-soak losses means...

40 CFR 86.082-2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., fully enclosing the driver compartment and load carrying device, and having no body sections protruding... the requirements of engine starting. Diurnal breathing losses means evaporative emissions as a result... barometric test conditions of 83.3 kPa (24.2 inches Hg), plus or minus 1 kPa (0.30 Hg). Hot-soak losses means...

40 CFR 86.082-2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., fully enclosing the driver compartment and load carrying device, and having no body sections protruding... the requirements of engine starting. Diurnal breathing losses means evaporative emissions as a result... barometric test conditions of 83.3 kPa (24.2 inches Hg), plus or minus 1 kPa (0.30 Hg). Hot-soak losses means...

40 CFR 409.13 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Beet Sugar Processing... a point source where the sugar beet processing capacity of the point source does not exceed 1090 kkg... results, in whole or in part, from barometric condensing operations and any other beet sugar processing...

40 CFR 409.13 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Beet Sugar Processing... a point source where the sugar beet processing capacity of the point source does not exceed 1090 kkg... results, in whole or in part, from barometric condensing operations and any other beet sugar processing...

40 CFR 409.13 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SUGAR PROCESSING POINT SOURCE CATEGORY Beet Sugar Processing... a point source where the sugar beet processing capacity of the point source does not exceed 1090 kkg... results, in whole or in part, from barometric condensing operations and any other beet sugar processing...

Miscellaneous chemical basin expedited site characterization report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riha, B.D.; Pemberton, B.E.; Rossabi, J.

1996-12-01

A total of twenty nine cone penetrometer test (CPT) pushes in three weeks were conducted for vadose zone characterization of the Miscellaneous Chemical Basin (MCB) waste unit at the Savannah River Site. The shallow, unlined basin received liquid chemical wastes over an 18 year period beginning in 1956. This characterization was initiated to determine the vertical and lateral extent of contamination in the vadose zone and to install vadose zone wells for remediation by barometric pumping or active vapor extraction to help prevent further contamination of groundwater. The CPT locations within the waste site were selected based on results frommore » previous shallow soil gas surveys, groundwater contamination data, and the suspected basin center. Geophysical data and soil gas samples were collected at twenty five locations and twenty five vadose zone wells were installed. The wells were screened to target the clay zones and areas of higher soil gas concentrations. The well construction diagrams are provided in Appendix B. Baro-Ball{trademark} valves for enhanced barometric pumping were installed on each well upon completion to immediately begin the remediation treatability study at the site.« less

Research and Development of An In-situ Real-time Coastal Monitoring System

NASA Astrophysics Data System (ADS)

Deponte, D.; Cecco, R.; Laterza, R.; Medeot, N.; Nair, R.; Viezzoli, D.

The coastal area is a complex system in which the effects of the forcing terms on the circulation and mixing present a marked space-time variability on widely differing scales. In order to study such a system, it is necessary to monitor continuously, at high frequency, oceanographic and meteorological variables. To meet this need, the OGS has developed a coastal meteo-oceanographic buoy, called MAMBO, constituted by a float, a hull, a tripod and a powering system based on batteries recharged by so- lar panels that have been expressly designed and assembled by an in-house technical team. The buoy is equipped with a mechanical winch driving a multi-parametric pro- filing probe which provides data on pressure, temperature, salinity, dissolved oxygen, chlorophyll, pH and turbidity over the entire water column. Meteorological data (air temperature, barometric pressure and wind) are also measured. Data are acquired ev- ery 3 hours and transmitted via GSM cellular phone to a receiving station at the OGS in real-time where they are automatically subjected to a first level quality-check and made available to the public at the OGS web site. The buoy also serves as a convenient platform for a separate OGS-developed controller that manages an upward-looking ADCP-600kHz positioned on the sea floor close to the buoy. This controller regu- lates the ADCP power supply and permits the real-time transmission of pressure and current data to land via GSM cellular phone. Since there are no limitations due to bat- teries or memory capacity, currents can be sampled at high spatial and time resolution. Moreover, the controller permits to remotely change the configuration of the instru- ment in order to increase, for example, vertical resolution, and eventually, to record wave data. The first buoy of this type has been operating in the Gulf of Trieste (North Adriatic Sea) since 1998, and it is being continually improved. Two others, supplied additionally with a GPS, a radiometer and a hygrometer and improved with respect to some mechanical parts, have been deployed since June 2000, in the coastal area to the north of Sardinia (Tyrrhenian Sea). The development of an effective quality control procedure, that can be applied in real-time to the acquired data and that can permit the design of an efficient maintenance program for the buoy sensors, is in progress.

Map showing radon potential of rocks and soils in Montgomery County, Maryland

USGS Publications Warehouse

Gundersen, L.C.; Reimer, G.M.; Wiggs, C.R.; Rice, C.A.

1988-01-01

This report summarizes the radon potential of Montgomery County in the context of its geology. Radon is a naturally occurring gas produced by the radioactive decay of uranium. Radon produced by uraniferous rocks and soils may enter a house through porous building materials and through openings in walls and floors. Radon gases has a tendency to move from the higher pressure commonly existing in the soil to the lower pressure commonly existing in the house. The U.S. Environmental Protection Agency (U.S. EPA, 1986a) estimates that elevated levels of indoor radon may be associated with 5,000 to 20,000 of the 130,000 lung cancer deaths per year. They also estimate that 8 to 12 percent of the homes in the United States will have annual average indoor radon levels exceeding 4 picoCuries per liter of air (pCi/L). Above this level, the U.S. EPA recommends homeowners take remedial action. May factors control the amount of radon which may enter a home from the geologic environment. Soil drainage, permeability, and moisture content effect the amount of radon that can be released from rocks and soils (known as the emmanation) and may limit or increase how far it can migrate. Well drained, highly permeable soils facilitate the movement of radon. Soils with water content in the 8 to 15 percent range enhance the emmanation of radon (Lindmark, 1985). Daily and seasonal variations in soil and indoor radon can be caused by meteorologic factors such as barometric pressure, temperature, and wind (Clements and Wilkening, 1974; Schery and other, 1984). Construction practices also inhibit or promote entry of radon into the home (U.S. EPA, 1986b). In general, however, geology controls the source and distribution of radon (Akerblom and Wilson, 1982; Gundersen and others, 1987, 1988; Sextro and others, 1987; U.S. EPA, 1983; Peake, 1988; Peake and Hess, 1988). The following sections describe: 1) the methods used to measure radon and equivalent uranium (eU) in soil; 2) the radon potential ratings that were developed for this study; and 3) the characteristics of the rocks and soils in Montgomery County that give them their radon potential.

Estimating hydraulic properties of the Floridan Aquifer System by analysis of earth-tide, ocean-tide, and barometric effects, Collier and Hendry Counties, Florida

USGS Publications Warehouse

Merritt, Michael L.

2004-01-01

Aquifers are subjected to mechanical stresses from natural, non-anthropogenic, processes such as pressure loading or mechanical forcing of the aquifer by ocean tides, earth tides, and pressure fluctuations in the atmosphere. The resulting head fluctuations are evident even in deep confined aquifers. The present study was conducted for the purpose of reviewing the research that has been done on the use of these phenomena for estimating the values of aquifer properties, and determining which of the analytical techniques might be useful for estimating hydraulic properties in the dissolved-carbonate hydrologic environment of southern Florida. Fifteen techniques are discussed in this report, of which four were applied.An analytical solution for head oscillations in a well near enough to the ocean to be influenced by ocean tides was applied to data from monitor zones in a well near Naples, Florida. The solution assumes a completely non-leaky confining unit of infinite extent. Resulting values of transmissivity are in general agreement with the results of aquifer performance tests performed by the South Florida Water Management District. There seems to be an inconsistency between results of the amplitude ratio analysis and independent estimates of loading efficiency. A more general analytical solution that takes leakage through the confining layer into account yielded estimates that were lower than those obtained using the non-leaky method, and closer to the South Florida Water Management District estimates. A numerical model with a cross-sectional grid design was applied to explore additional aspects of the problem.A relation between specific storage and the head oscillation observed in a well provided estimates of specific storage that were considered reasonable. Porosity estimates based on the specific storage estimates were consistent with values obtained from measurements on core samples. Methods are described for determining aquifer diffusivity by comparing the time-varying drawdown in an open well with periodic pressure-head oscillations in the aquifer, but the applicability of such methods might be limited in studies of the Floridan aquifer system.

Optimizing detection of noble gas emission at a former UNE site: sample strategy, collection, and analysis

NASA Astrophysics Data System (ADS)

Kirkham, R.; Olsen, K.; Hayes, J. C.; Emer, D. F.

2013-12-01

Underground nuclear tests may be first detected by seismic or air samplers operated by the CTBTO (Comprehensive Nuclear-Test-Ban Treaty Organization). After initial detection of a suspicious event, member nations may call for an On-Site Inspection (OSI) that in part, will sample for localized releases of radioactive noble gases and particles. Although much of the commercially available equipment and methods used for surface and subsurface environmental sampling of gases can be used for an OSI scenario, on-site sampling conditions, required sampling volumes and establishment of background concentrations of noble gases require development of specialized methodologies. To facilitate development of sampling equipment and methodologies that address OSI sampling volume and detection objectives, and to collect information required for model development, a field test site was created at a former underground nuclear explosion site located in welded volcanic tuff. A mixture of SF-6, Xe127 and Ar37 was metered into 4400 m3 of air as it was injected into the top region of the UNE cavity. These tracers were expected to move towards the surface primarily in response to barometric pumping or through delayed cavity pressurization (accelerated transport to minimize source decay time). Sampling approaches compared during the field exercise included sampling at the soil surface, inside surface fractures, and at soil vapor extraction points at depths down to 2 m. Effectiveness of various sampling approaches and the results of tracer gas measurements will be presented.

Superconductor-Mediated Modification of Gravity? AC Motor Experiments with Bulk YBCO Disks in Rotating Magnetic Fields

NASA Technical Reports Server (NTRS)

Noever, David A.; Koczor, Ronald J.; Roberson, Rick

1998-01-01

We have previously reported results using a high precision gravimeter to probe local gravity changes in the neighborhood of large bulk-processed high-temperature superconductors. Podkietnov, et al (Podkietnov, E. and Nieminen, R. (1992) A Possibility of Gravitational Force Shielding by Bulk YBa2 Cu3 O7-x Superconductor, Physica C, C203:441-444.) have indicated that rotating AC fields play an essential role in their observed distortion of combined gravity and barometric pressure readings. We report experiments on large (15 cm diameter) bulk YBCO ceramic superconductors placed in the core of a three-phase, AC motor stator. The applied rotating field produces up to a 12,000 revolutions per minute magnetic field. The field intensity decays rapidly from the maximum at the outer diameter of the superconducting disk (less than 60 Gauss) to the center (less than 10 Gauss). This configuration was applied with and without a permanent DC magnetic field levitating the superconducting disk, with corresponding gravity readings indicating an apparent increase in observed gravity of less than 1 x 10(exp -6)/sq cm, measured above the superconductor. No effect of the rotating magnetic field or thermal environment on the gravimeter readings or on rotating the superconducting disk was noted within the high precision of the observation. Implications for propulsion initiatives and power storage flywheel technologies for high temperature superconductors will be discussed for various spacecraft and satellite applications.

Modeling of Permeability Structure Using Pore Pressure and Borehole Strain Monitoring

NASA Astrophysics Data System (ADS)

Kano, Y.; Ito, H.

2011-12-01

Hydraulic or transport property, especially permeability, of the rock affect the behavior of the fault during earthquake rupture and also interseismic period. The methods to determine permeability underground are hydraulic test utilizing borehole and packer or core measurement in laboratory. Another way to know the permeability around a borehole is to examine responses of pore pressure to natural loading such as barometric pressure change at surface or earth tides. Using response to natural deformation is conventional method for water resource research. The scale of measurement is different among in-situ hydraulic test, response method, and core measurement. It is not clear that the relationship between permeability values form each method for an inhomogeneous medium such as a fault zone. Supposing the measurement of the response to natural loading, we made a model calculation of permeability structure around a fault zone. The model is 2 dimensional and constructed with vertical high-permeability layer in uniform low-permeability zone. We assume the upper and lower boundaries are drained and no-flow condition. We calculated the flow and deformation of the model for step and cyclic loading by numerically solving a two-dimensional diffusion equation. The model calculation shows that the width of the high-permeability zone and contrast of the permeability between high- and low- permeability zones control the contribution of the low-permeability zone. We made a calculation with combinations of permeability and fault width to evaluate the sensitivity of the parameters to in-situ measurement of permeability. We applied the model calculation to the field results of in-situ packer test, and natural response of water level and strain monitoring carried out in the Kamioka mine. The model calculation shows that knowledge of permeability in host rock is also important to obtain permeability of fault zone itself. The model calculations help to design long-term pore pressure monitoring, in-situ hydraulic test, and core measurement using drill holes to better understand fault zone hydraulic properties.

KPOT_wlanger_1: State of the Diffuse ISM: Galactic Observations of the Terahertz CII Line (GOT CPlus)

NASA Astrophysics Data System (ADS)

Langer, W.

2007-10-01

Star formation activity throughout the Galactic disk depends on the thermal and dynamical state of the interstellar gas, which in turn depends on heating and cooling rates, modulated by the gravitational potential and shock and turbulent pressures. Molecular cloud formation, and thus the star formation, may be regulated by pressures in the interstellar medium (ISM). To understand these processes we need information about the properties of the diffuse atomic and diffuse molecular gas clouds, and Photon Dominated Regions (PDR). An important tracer of these regions is the CII line at 158 microns (1900.5 GHz). We propose a "pencil-beam" survey of CII with HIFI band 7b, based on deep integrations and systematic sparse sampling of the Galactic disk plus selected targets, totaling over 900 lines of sight. We will detect both emission and, against the bright inner Galaxy and selected continuum sources, absorption lines. These spectra will provide the astronomical community with a large rich statistical database of the diffuse cloud properties throughout the Galaxy for understanding the Milky Way ISM and, by extension, other galaxies. It will be extremely valuable for determining the properties of the atomic gas, the role of barometric pressure and turbulence in cloud evolution, and the properties of the interface between the atomic and molecular clouds. The CII line is one of the major ISM cooling lines and is present throughout the Galactic plane. It is the strongest far-IR emission line in the Galaxy, with a total luminosity about a 1000 times that of the CO J=1-0 line. Combined with other data, it can be used to determine density, pressure, and radiation environment in gas clouds, and PDRs, and their dynamics via velocity fields. HSO is the best opportunity over the next several years to probe the ISM in this tracer and will provide a template for large-scale surveys with dedicated small telescopes and future surveys of other important ISM tracers.

SDP_wlanger_3: State of the Diffuse ISM: Galactic Observations of the Terahertz CII Line (GOT CPlus)

NASA Astrophysics Data System (ADS)

Langer, W.

2011-09-01

Star formation activity throughout the Galactic disk depends on the thermal and dynamical state of the interstellar gas, which in turn depends on heating and cooling rates, modulated by the gravitational potential and shock and turbulent pressures. Molecular cloud formation, and thus the star formation, may be regulated by pressures in the interstellar medium (ISM). To understand these processes we need information about the properties of the diffuse atomic and diffuse molecular gas clouds, and Photon Dominated Regions (PDR). An important tracer of these regions is the CII line at 158 microns (1900.5 GHz). We propose a "pencil-beam" survey of CII with HIFI band 7b, based on deep integrations and systematic sparse sampling of the Galactic disk plus selected targets, totaling over 900 lines of sight. We will detect both emission and, against the bright inner Galaxy and selected continuum sources, absorption lines. These spectra will provide the astronomical community with a large rich statistical database of the diffuse cloud properties throughout the Galaxy for understanding the Milky Way ISM and, by extension, other galaxies. It will be extremely valuable for determining the properties of the atomic gas, the role of barometric pressure and turbulence in cloud evolution, and the properties of the interface between the atomic and molecular clouds. The CII line is one of the major ISM cooling lines and is present throughout the Galactic plane. It is the strongest far-IR emission line in the Galaxy, with a total luminosity about a 1000 times that of the CO J=1-0 line. Combined with other data, it can be used to determine density, pressure, and radiation environment in gas clouds, and PDRs, and their dynamics via velocity fields. HSO is the best opportunity over the next several years to probe the ISM in this tracer and will provide a template for large-scale surveys with dedicated small telescopes and future surveys of other important ISM tracers.

A time series study on the effects of cold temperature on road traffic injuries in Seoul, Korea.

PubMed

Lee, Won-Kyung; Lee, Hye-Ah; Hwang, Seung-sik; Kim, Ho; Lim, Youn-Hee; Hong, Yun-Chul; Ha, Eun-Hee; Park, Hyesook

2014-07-01

Although traffic accidents are associated with weather, the influence of temperature on injuries from traffic accidents has not been evaluated sufficiently. The objective of this study was to evaluate the effect of temperature, especially cold temperatures, on injuries from traffic accidents in Seoul, Korea. We also explored the relationship of temperature with different types of traffic accident. The daily frequencies of injuries from traffic accidents in Seoul were summarized from the integrated database established by the Korea Road Traffic Authority. Weather data included temperature, barometric pressure, rainfall, snow, and fog from May 2007 to December 2011. The qualitative relationship between daily mean temperature and injuries from traffic accidents was evaluated using a generalized additive model with Poisson distribution. Further analysis was performed using piecewise linear regression if graph the showed non-linearity with threshold. The incidence of injuries was 216 per 100,000 person-months in Seoul. The effect of temperature on injuries from traffic accidents was minimal during spring and summer. However, injuries showed a more striking relationship with temperature in winter than in other seasons. In winter, the number of injuries increased as the temperature decreased to <0°C. The injuries increased by 2.1% per 1°C decrease under the threshold of the daily average temperature -5.7°C, which is 10-fold greater than the effect of temperature above the threshold. Some groups were more susceptible to injuries, such as young and male drivers, according to the types of traffic accident when the temperature decreased to below the freezing temperature. The incidence of injuries increased sharply when the temperature decreased below freezing temperature in winter. Temperature can be effectively used to inform high risk of road traffic injuries, thus helping to prevent road traffic injuries. Copyright © 2014 Elsevier Inc. All rights reserved.

Association of Ambient Air Pollution with Respiratory Hospitalization in a Government-Designated “Area of Concern”: The Case of Windsor, Ontario

PubMed Central

Luginaah, Isaac N.; Fung, Karen Y.; Gorey, Kevin M.; Webster, Greg; Wills, Chris

2005-01-01

This study is part of a larger research program to examine the relationship between ambient air quality and health in Windsor, Ontario, Canada. We assessed the association between air pollution and daily respiratory hospitalization for different age and sex groups from 1995 to 2000. The pollutants included were nitrogen dioxide, sulfur dioxide, carbon monoxide, ozone, particulate matter ≤10 μm in diameter (PM10), coefficient of haze (COH), and total reduced sulfur (TRS). We calculated relative risk (RR) estimates using both time-series and case-crossover methods after controlling for appropriate confounders (temperature, humidity, and change in barometric pressure). The results of both analyses were consistent. We found associations between NO2, SO2, CO, COH, or PM10 and daily hospital admission of respiratory diseases especially among females. For females 0–14 years of age, there was 1-day delayed effect of NO2 (RR = 1.19, case-crossover method), a current-day SO2 (RR = 1.11, time series), and current-day and 1- and 2-day delayed effects for CO by case crossover (RR = 1.15, 1.19, 1.22, respectively). Time-series analysis showed that 1-day delayed effect of PM10 on respiratory admissions of adult males (15–64 years of age), with an RR of 1.18. COH had significant effects on female respiratory hospitalization, especially for 2-day delayed effects on adult females, with RRs of 1.15 and 1.29 using time-series and case-crossover analysis, respectively. There were no significant associations between O3 and TRS with respiratory admissions. These findings provide policy makers with current risks estimates of respiratory hospitalization as a result of poor ambient air quality in a government designated “area of concern.” PMID:15743717

Modeling Navigation System Performance of a Satellite-Observing Star Tracker Tightly Integrated with an Inertial Measurement Unit

DTIC Science & Technology

2015-03-26

tracker, an Inertial Measurement Unit (IMU), and a barometric altimeter using an Extended Kalman Filter (EKF). Models of each of these components are...Positioning 15 2.5 Detector Device Improvement . . . . . . . . . . . . . . . 15 2.6 Kalman Filter . . . . . . . . . . . . . . . . . . . . . . . . 17 2.6.1...Extended Kalman Filter . . . . . . . . . . . . . 17 2.7 System Properties . . . . . . . . . . . . . . . . . . . . . 21 2.8 Sun Exitance

The Evaluation of a Risk Degree for the Process of a Brown Coal Spontaneous Ignition on Dumps with Using of Modern Numeric Methods

NASA Astrophysics Data System (ADS)

Klouda, Petr; Moni, Vlastimil; Řehoř, Michal; Blata, Jan; Helebrant, František

2018-06-01

The article is a summary of information about evaluation of a risk degree for a brown coal spontaneous ignition which is realized on the base of a database analysis of information about the development of stative quantities and desorbated gases in the stored bodies of the brown coal. The data were gained from the long term complex measurements which were realized at chosen companies during the coal mining in the previous parts of the project. In the last part of the project, we examined results of temperature models from thermographs with results of gasses and coal samples from the mines. Then, the influence of atmospheric conditions (insolation, water downfall, changes of barometric pressure etc.), the influence of coal mass degradation, the influence of physical and chemical factors, and the influence of other defective factors on the process of the coal spontaneous ignition. The gasmetry was assess with gas in-situ samples and laboratory gas models of indicative gasses for the spontaneous ignition, which were taken from the method of the thermic oxidation with the aim of the correlation finding for an epicentre of temperature within the spontaneous ignition.

Water-Quality Data for the Lower Russian River Basin, Sonoma County, California, 2003-2004

USGS Publications Warehouse

Anders, Robert; Davidek, Karl; Koczot, Kathryn M.

2006-01-01

In 2003, the U.S. Geological Survey, in cooperation with the Sonoma County Water Agency, began a study to determine the chemical, microbiological, and isotopic composition of the surface water and ground water in selected areas of the Lower Russian River Basin, Sonoma County, California. This report is a compilation of the hydrologic and water-quality data collected from 10 Russian River sites, 1 gravel-terrace pit site, 12 ground-water sites, 11 tributary sites including Mark West Creek, and 2 estuary sites between the city of Healdsburg and the Pacific Ocean, for the period August 2003 to September 2004. Field measurements made included streamflow, barometric pressure, dissolved oxygen, pH, specific conductance, and turbidity. Water samples were analyzed for nutrients, major ions, total and dissolved organic carbon, trace elements, mercury, wastewater compounds, total coliform, Escherichia coli, Enterococci, Clostridium perfringens, and the stable isotopes of hydrogen and oxygen. Discharge measurements and sampling techniques were modified to accommodate the very low summer flows at most of the tributaries, and discharge measurements were made with an acoustic Doppler velocity meter at the estuary river site to overcome the complexities associated with tidal influences.

Meteorological factors and timing of the initiating event of human parturition

NASA Astrophysics Data System (ADS)

Hirsch, Emmet; Lim, Courtney; Dobrez, Deborah; Adams, Marci G.; Noble, William

2011-03-01

The aim of this study was to determine whether meteorological factors are associated with the timing of either onset of labor with intact membranes or rupture of membranes prior to labor—together referred to as `the initiating event' of parturition. All patients delivering at Evanston Hospital after spontaneous labor or rupture of membranes at ≥20 weeks of gestation over a 6-month period were studied. Logistic regression models of the initiating event of parturition using clinical variables (maternal age, gestational age, parity, multiple gestation and intrauterine infection) with and without the addition of meteorological variables (barometric pressure, temperature and humidity) were compared. A total of 1,088 patients met the inclusion criteria. Gestational age, multiple gestation and chorioamnionitis were associated with timing of initiation of parturition ( P < 0.01). The addition of meteorological to clinical variables generated a statistically significant improvement in prediction of the initiating event; however, the magnitude of this improvement was small (less than 2% difference in receiver-operating characteristic score). These observations held regardless of parity, fetal number and gestational age. Meteorological factors are associated with the timing of parturition, but the magnitude of this association is small.

Multi-channel Auto-dilution System for Remote Continuous Monitoring of High Soil-CO2 Fluxes

NASA Astrophysics Data System (ADS)

Barr, J. L.; Amonette, J. E.

2008-12-01

We describe a novel field instrument that takes input from up to 27 soil flux chambers and measures flux using the steady-state method. CO2 concentrations are determined with an infrared gas analyzer (IRGA, 0- 3000 ppmv range) with corrections for temperature, barometric pressure, and moisture content. The concentrations are monitored during data collection and, if they exceed the range of the IRGA, a stepped dilution program is automatically implemented that allows up to 50-fold dilution of the incoming gas stream with N2 supplied by boil-off from a large dewar. The upper concentration limit of the system with dilution is extended to at least 150,000 ppmv CO2. The data are stored on a datalogger having a cellular modem connection that allows remote control of the system as well as transmittal of data. The system is designed to operate for six weeks with no on-site maintenance required. Longer periods are possible with modifications to allow on-site generation of N2 from air. Example data from a recent CO2 test injection at the Zero- Emission Research and Technology (ZERT) field site in Bozeman, MT are presented.

Terminal area automatic navigation, guidance, and control research using the Microwave Landing System (MLS). Part 2: RNAV/MLS transition problems for aircraft

NASA Technical Reports Server (NTRS)

Pines, S.

1982-01-01

The problems in navigation and guidance encountered by aircraft in the initial transition period in changing from distance measuring equipment, VORTAC, and barometric instruments to the more precise microwave landing system data type navaids in the terminal area are investigated. The effects of the resulting discontinuities on the estimates of position and velocity for both optimal (Kalman type navigation schemes) and fixed gain (complementary type) navigation filters, and the effects of the errors in cross track, track angle, and altitude on the guidance equation and control commands during the critical landing phase are discussed. A method is presented to remove the discontinuities from the navigation loop and to reconstruct an RNAV path designed to land the aircraft with minimal turns and altitude changes.

Acute morphine effects on respiratory activity in mice with target deletion of the tachykinin 1 gene (Tac1-/-).

PubMed

Shvarev, Yuri; Berner, Jonas; Bilkei-Gorzo, Andras; Lagercrantz, Hugo; Wickström, Ronny

2010-01-01

Search for physiological mechanisms which could antagonize the opioid-induced respiratory depression is of important clinical value. In this study, we investigated the acute effects of morphine on respiratory activity in genetically modified newborn (P2) mice with target deletion of the (Tac1 -/-) gene lacking substance P (SP) and neurokinin A (NKA). In vivo, as shown with whole-body flow barometric plethysmography technique, morphine induced significantly attenuated minute ventilation during intermittent hypoxia in control animals. In contrast, knockout mice revealed significant increase in minute ventilation. In vitro, in brainstem preparation, knockout mice demonstrated greater changes in burst frequency during intermittent anoxia challenge. The data suggest that hereditary deficiency in tachykinins, SP and NKA results in more robust hypoxic response in newborn Tac1-/- mice during respiratory depression induced by morphine.

A Novel Wireless Wearable Volatile Organic Compound (VOC) Monitoring Device with Disposable Sensors.

PubMed

Deng, Yue; Chen, Cheng; Xian, Xiaojun; Tsow, Francis; Verma, Gaurav; McConnell, Rob; Fruin, Scott; Tao, Nongjian; Forzani, Erica S

2016-12-03

A novel portable wireless volatile organic compound (VOC) monitoring device with disposable sensors is presented. The device is miniaturized, light, easy-to-use, and cost-effective. Different field tests have been carried out to identify the operational, analytical, and functional performance of the device and its sensors. The device was compared to a commercial photo-ionization detector, gas chromatography-mass spectrometry, and carbon monoxide detector. In addition, environmental operational conditions, such as barometric change, temperature change and wind conditions were also tested to evaluate the device performance. The multiple comparisons and tests indicate that the proposed VOC device is adequate to characterize personal exposure in many real-world scenarios and is applicable for personal daily use.

A Novel Wireless Wearable Volatile Organic Compound (VOC) Monitoring Device with Disposable Sensors

PubMed Central

Deng, Yue; Chen, Cheng; Xian, Xiaojun; Tsow, Francis; Verma, Gaurav; McConnell, Rob; Fruin, Scott; Tao, Nongjian; Forzani, Erica S.

2016-01-01

A novel portable wireless volatile organic compound (VOC) monitoring device with disposable sensors is presented. The device is miniaturized, light, easy-to-use, and cost-effective. Different field tests have been carried out to identify the operational, analytical, and functional performance of the device and its sensors. The device was compared to a commercial photo-ionization detector, gas chromatography-mass spectrometry, and carbon monoxide detector. In addition, environmental operational conditions, such as barometric change, temperature change and wind conditions were also tested to evaluate the device performance. The multiple comparisons and tests indicate that the proposed VOC device is adequate to characterize personal exposure in many real-world scenarios and is applicable for personal daily use. PMID:27918484

Long Term Autonomous Ocean Remote Sensing Utilizing the Wave Glider

NASA Astrophysics Data System (ADS)

Griffith, J.

2012-12-01

Rising costs of ship time and increasing budgetary restrictions make installation and maintenance of fixed ocean buoys a logistical and financial challenge. The cost associated with launch, recovery, and maintenance has resulted in a limited number of deployed buoys, restricting data on oceanic conditions. To address these challenges, Liquid Robotics (LRI) has developed the Wave Glider, an autonomous, mobile remote sensing solution. This system utilizes wave energy for propulsion allowing for long duration deployments of up to one year while providing real-time data on meteorological and oceanographic conditions. In November 2011, LRI deployed four Wave Gliders on a mission to cross the Pacific Ocean (the PacX) from San Francisco to Australia (two vehicles) or Japan (two vehicles) while transmitting data on weather conditions, wave profiles, sea surface temperatures, and biological conditions in real-time. This report evaluates the vehicle's ability to operate as an ocean going data platform by comparing data from the onboard weather sensors with two moored buoys, NDBC 46092 (Monterey Bay) and NDBC 51000 (200 nmi NE of Maui). The report also analyzes data transmitted from all four vehicles as they passed directly through a tropical storm 580 nmi NE of Hawaii. Upon arriving at one of the aforementioned buoys, the gliders continuously circled for a period of two days at a distance of three to eight nautical miles to build a comparative dataset. Data from both platforms were streamed in near real time enabling mid-mission evaluation of the performance of sensors. Overall, results varied from a <0.5% difference in barometric pressure between buoy NDBC 46092 and the gliders to high disagreement in wind speed and direction. While comparisons to moored buoy data can provide valuable insight into the relative accuracy of each platform, differences in agreement on variables such as wind speed and direction were attributed to micro-spatial variability in oceanic conditions. In addition, all four PacX vehicles collected data from directly within a tropical storm off the coast of Hawaii. Starting on February 5th, 2012, the vehicles measured sustained winds of 40 knots for 4 days with gusts up to 80 knots at the height of the storm. The vehicles also measured sustained wave heights of 7m along with a barometric pressure drop to a low of 985 mbar. A pressure between 965 and 979 mbar is comparable to a category two hurricane while the measured wind speed falls within the range of a tropical storm on the SSHS. The wind data compares favorably to satellite imagery from the ASCAT satellite data of the same storm but with much higher spatial resolution. In conclusion, the Pacific crossing has provided solid evidence that the Wave Glider would provide a suitable and highly efficient platform for the observation of sea surface and lower atmospheric conditions over extended sampling periods. The system could be used to quickly and efficiently increase the operational density of ocean observations without the need for expensive deployment and recovery vessels. In future studies, data from the PacX will be compared with additional satellite and oceanic data sources to provide ground truthing of collected oceanographic data. In addition, two Wave Gliders will be deployed from Puerto Rico to monitor storm conditions from directly within a hurricane.

Relationships of barometric pressure and environmental temperature with incidence of parturition in beef cows.

PubMed

Troxel, T R; Gadberry, M S

2012-05-01

The relationship between barometric pressure (BARO) and maximum (MAX_T) and minimum (MIN_T) environmental temperatures with the incidence of parturition in beef cows was examined through exploratory data analysis. Spring- and fall-calving records from a 5-yr period (2005 through 2009) collected at the University of Arkansas, Livestock and Forestry Research Station (Batesville) and the Department of Animal Science Savoy Research Unit (Savoy, AR) were used. All cows were multiparous, predominantly Angus, and naturally bred. During this period, 2,210 calves were born over a cumulative 1,547 d. Local weather station BARO and MAX_T and MIN_T data were obtained from the Southern Regional Climate Center, Louisiana State University, Baton Rouge. The combined calving record and climate variables were used to determine differences in BARO, MAX_T, and MIN_T on d 0 (d of calving) and -1, -2, or -3 d, respectively, before calving occurred (CALFD) or did not occur (NOCALFD). Location and season also were included in the model. For fall-calving cows, BARO on d 0 and -1, -2, or -3 was not different between CALFD and NOCALFD (P > 0.10). For spring-calving cows, BARO on d 0, -1, -2, and -3 was greater (P < 0.05) for CALFD compared with NOCALFD. The MAX_T was greater on d -1 (24.4 vs. 22.9°C) and -3 (24.8 vs. 23.4°C) for CALFD in the fall compared with NOCALFD (P < 0.05). No differences were detected in the fall for MAX_T on d 0 or -2 (P > 0.10). In the spring, a decreased MAX_T was associated with CALFD. Maximum environmental temperatures on d 0 (14.7 vs. 16.0°C), -1 (14.4 vs. 16.0°C), and -3 (14.0 vs. 15.7°C) were less for CALFD compared with NOCALFD (P < 0.05). No difference was detected on d -2 (P > 0.10). For fall, MIN_T was greater on d -1 (12.8 vs. 11.3°C), -2 (13.0 vs. 11.4°C), and -3 (13.1 vs. 11.7°C) for CALFD compared with NOCALFD (P < 0.05). In spring, MIN_T for d 0 (2.6 vs. 3.9°C), -1 (2.5 vs. 3.7°C), -2 (2.1 vs. 3.7°C), and -3 (1.8 vs. 3.8°C) were lesser (P < 0.05) for CALFD vs. NOCALFD. These data indicate that for spring-calving cows, a greater BARO and decreased MAX_T and MIN_T were associated with CALFD, whereas for fall-calving cows, an increase in MAX_T and MIN_T was associated with CALFD. Therefore, monitoring weather conditions may assist producers in preparing for the obstetric assistance of beef cattle.

Effect of metabolic gases and water vapor, perfluorocarbon emulsions, and nitric oxide on tissue bubbles during decompression sickness.

PubMed

Randsøe, Thomas

2016-05-01

In aviation and diving, fast decrease in ambient pressure, such as during accidental loss of cabin pressure or when a diver decompresses too fast to sea level, may cause nitrogen (N2) bubble formation in blood and tissue resulting in decompression sickness (DCS). Conventional treatment of DCS is oxygen (O2) breathing combined with recompression.  However, bubble kinetic models suggest, that metabolic gases, i.e. O2 and carbon dioxide (CO2), and water vapor contribute significantly to DCS bubble volume and growth at hypobaric altitude exposures. Further, perfluorocarbon emulsions (PFC) and nitric oxide (NO) donors have, on an experimental basis, demonstrated therapeutic properties both as treatment and prophylactic intervention against DCS. The effect was ascribed to solubility of respiratory gases in PFC, plausible NO elicited nuclei demise and/or N2 washout through enhanced blood flow rate. Accordingly, by means of monitoring injected bubbles in exposed adipose tissue or measurements of spinal evoked potentials (SEPs) in anaesthetized rats, the aim of this study was to: 1) evaluate the contribution of metabolic gases and water vapor to bubble volume at different barometrical altitude exposures, 2) clarify the O2 contribution and N2 solubility from bubbles during administration of PFC at normo- and hypobaric conditions and, 3) test the effect of different NO donors on SEPs during DCS upon a hyperbaric air dive and, to study the influence of  NO on tissue bubbles at high altitude exposures. The results support the bubble kinetic models and indicate that metabolic gases and water vapor contribute significantly to bubble volume at 25 kPa (~10,376 m above sea level) and constitute a threshold for bubble stabilization or decay at the interval of 47-36 kPa (~6,036 and ~7,920 m above sea level). The effect of the metabolic gases and water vapor seemed to compromise the therapeutic properties of both PFC and NO at altitude, while PFC significantly increased bubble disappearance rate at sea level following a hyperbaric airdive. We found no protective effect of NO donors during DCS from diving. On the contrary, there was a tendency towards a poorer outcome when decompression was combined with NO donor administration. This observation is seemingly contradictive to recent publications and may be explained by the multifactorial effect of NO in combination with a fast decompression profile, speeding up the N2 release from tissues and thereby aggravating the DCS symptoms.

Use of hydraulic head to estimate volumetric gas content and ebullition flux in northern peatlands

USGS Publications Warehouse

Rosenberry, Donald O.; Glaser, Paul H.; Siegel, Donald I.; Weeks, Edwin P.

2003-01-01

Hydraulic head was overpressured at middepth in a 4.2‐m thick raised bog in the Glacial Lake Agassiz peatlands of northern Minnesota, and fluctuated in response to atmospheric pressure. Barometric efficiency (BE), determined by calculating ratios of change in hydraulic head to change in atmospheric pressure, ranged from 0.05 to 0.15 during July through November of both 1997 and 1998. The overpressuring and a BE response were caused by free‐phase gas contained primarily in the center of the peat column between two or more semielastic, semiconfining layers of more competent peat. Two methods were used to determine the volume of gas bubbles contained in the peat, one using the degree of overpressuring in the middepth of the peat, and the other relating BE to specific yield of the shallow peat. The volume of gas calculated from the overpressuring method averaged 9%, assuming that the gas was distributed over a 2‐m thick overpressured interval. The volume of gas using the BE method averaged 13%. Temporal changes in overpressuring and in BE indicate that the volume of gaseous‐phase gas also changed with time, most likely because of rapid degassing (ebullition) that allowed sudden loss of gas to the atmosphere. Estimates of gas released during the largest ebullition events ranged from 0.3 to 0.7 mol m−2 d−1. These ebullition events may contribute a significant source of methane and carbon dioxide to the atmosphere that has so far largely gone unmeasured by gas‐flux chambers or tower‐mounted sensors.

The association between airline flight and sinonasal symptoms.

PubMed

Shargorodsky, Josef; Zheng, Laura; Stillman, Frances; Soong, Andrea; Navas-Acien, Ana; Reh, Douglas

2016-04-01

Airplane cabin supply air has been shown to contain multiple possible respiratory irritants. In addition, changes in barometric pressure in flight may contribute to specific respiratory conditions. Therefore, there may be an association between commercial airline flight and sinus disease. Participants of the Secondhand-Smoke, Air Quality and Respiratory Health Among Flight Attendants Study were administered an online questionnaire pertaining to their flight experience and respiratory health. Working years, working days per month, and number of trips per month were quantified, as well as smoking exposure and self-reported physician diagnoses of sinusitis, asthma, and rhinitis. The sinonasal outcomes were quantified using a Respiratory Questionnaire Survey (RQS) score. Multivariable analyses were performed to evaluate the associations between flight time and sinus disease. A total of 579 participants met the inclusion criteria for this study, with cohort prevalence of sinusitis, asthma, and rhinitis of 25.3%, 14.4%, and 20.5%, respectively. Tertiles 2 and 3 of working days per month were associated with higher RQS scores compared to tertile 1 (p for trend <0.01). Individual symptoms significantly associated with increasing number of working days per month included "need to blow nose," "sneezing," and "thick nasal discharge," and the number of international trips per month was significantly associated with "coughing" and "facial pain and pressure," among other symptoms. This is the largest study to analyze the relations between airline flight time and sinonasal disease. The results suggest a possible association between sinusitis diagnosis, symptom scores, and specific sinonasal symptoms, and airline flight time. © 2016 ARS-AAOA, LLC.

Impact of Hurricanes and Nor'easters on a Migrating Inlet System

NASA Astrophysics Data System (ADS)

Hopkins, J.; Elgar, S.; Raubenheimer, B.

2016-12-01

After breaching in 2007, Katama Inlet, connecting Katama Bay to the Atlantic Ocean on the south shore of Martha's Vineyard, MA, migrated 2 km until it closed in 2015. Bathymetric surveys before and after Hurricanes Irene (2011) and Sandy (2012) indicate the strong waves and currents associated with these storms caused 2 m of erosion and deposition around the inlet mouth. The waves, currents, and bathymetric change observed during the hurricanes were used to validate the hydrodynamic and morphodynamic components of a Delft3D numerical model of the Martha's Vineyard coastline for storm (> 3 m wave heights) conditions. When driven with observed bathymetry and offshore waves, as well as simulated (WaveWatch3) winds and barometric pressures, the model reproduces the pattern and range of bathymetric change observed around the inlet. Model simulations of realistic (i.e., Irene and Sandy) and idealized storm conditions with a range of durations and wave conditions are used to test the relative importance of short-duration, high-intensity storms (hurricanes) and longer-duration, lower-intensity storms (nor'easters) on inlet migration. The simulations suggest that longer-duration, lower-intensity storms cause a higher range and variance in bathymetric change around the inlet than shorter-duration, higher-intensity storms. However, the simulations also suggest that the storm-induced migration of the inlet depends more on the wave direction at the peak of the storm than on the duration of the storm peak. The effect of storms on inlet migration over yearly time scales will be discussed. Funded by NSF, NOAA, ONR, and ASD(R&E).

Environmental conditions affecting concentrations of He, CO2, O2 and N2 in soil gases

USGS Publications Warehouse

Hinkle, Margaret E.

1994-01-01

The measurement of concentrations of volatile species in soil gases has potential for use in geochemical exploration for concealed ore deposits and for monitoring of subsurface contaminants. However, the interpretation of anomalies in surficial gases can be difficult because soil-gas concentrations are dependent on both meteorological and environmental conditions.For this study, concentrations of He, CO2, O2 and N2 and meteorological conditions were monitored for 10–14 months at eight nonmineralized sites in both humid and dry environments. Gases were collected at 0.6–0.7-m depth at seven sites. At one site, gases were collected from 0.3-, 0.6-, 1.2-, and 2.0-m depths; diurnal monitoring studies were conducted at this site also. Rain and snowfall, soil and air temperatures, barometric pressure, and relative humidity were monitored at all the sites. The sand, silt and clay content, and the organic carbon content of surficial soil were measured at each site.Meteorological conditions generally affected He and CO2 concentrations in the same way at all the sites; however, these effects were modified by local environmental conditions. Both seasonal and diurnal concentration changes occurred. The most important seasonal concentration changes were related to rain and snowfall and soil and air temperatures. Seasonal changes tended to be larger then the diurnal changes, but both could be related to the same processes. Local conditions of soil type and organic content affected the amount of pore space and moisture present in the soil and therefore the soil-gas concentrations.

Investigation of the I-40 Jet-Propulsion Engine in the Cleveland Altitude Wind Tunnel. V - Operational Characteristics. 5; Operational Characteristics

NASA Technical Reports Server (NTRS)

Golladay, Richard L.; Gendler, Stanley L.

1947-01-01

An investigation has been conducted in the Cleveland altitude wind tunnel to determine the operational characteristics of the I-40 jet-propulsion engine over a range of pressure altitudes from 10,000 to 50,000 feet and ram-pressure ratios from 1.00 to 1.76. Engine operational data were obtained with the engine in the standard configuration and with various modifications of the fuel system, the electrical system, and the combustion chambers. The effects of altitude and airspeed on operating speed range, starting, windmilli.ng, acceleration, speed regulation, cooling, and vibration of the standard and modified engines were determined, and damage to parts was noted. Maximum engine speed was obtainable at all altitudes and airspeeds wi th each fuel-control system investigated. The minimum idling speed was raised by increases in altitude and airspeed. The lowest minimum stable speeds were obtained with the standard configuration using 40-gallon nozzles with individual metering plugs. The engine was started normally at altitudes as high as 20,000 feet with all of the fuel systems and ignition combinations except one. Ignition at 70,000 feet was difficult and, although successful ignition occurred, acceleration was slow and usually characterized by excessive tail-pipe temperature. During windmilling investigations of the engine equipped with the standard fuel system, the engine could not be started at ram-pressure ratios of 1.1 to 1.7 at altitudes of 10,000, 20,000 and 30,000 feet. When equipped with the production barometric and Monarch 40-gallon nozzles, the engine accelerated in 12 seconds from an engine speed of 6000 rpm to 11,000 rpm at 20,000 feet and an average tail-pipe temperature of 11000 F. At the same altitude and temperature, all the engine configurations had approximately the same rate of acceleration. The Woodward governor produced the safest accelerations, inasmuch as it could be adjusted to automatically prevent acceleration blow out. The engine speed was held constant by the Woodward governor and the Edwards regulator during simulated dives and climbs at constant throttle position. The bearing cooling system was satisfactory at all altitudes and airspeeds. The engines operated without serious failure, although the exhaust cone, the tail pipe, and the airplane fuselage were damaged during altitude starts.

Are the current thresholds, indicators, and time window for cold warning effective enough to protect cardiovascular health?

PubMed

Lin, Shao; Lawrence, Wayne R; Lin, Ziqiang; DiRienzo, Stephen; Lipton, Kevin; Dong, Guang-Hui; Leung, Ricky; Lauper, Ursula; Nasca, Philip; Stuart, Neil

2018-10-15

More extreme cold weather and larger weather variations have raised concerns regarding their effects on public health. Although prior studies assessed the effects of cold air temperature on health, especially mortality, limited studies evaluated wind chill temperatures on morbidity, and health effects under the current cold warning threshold. This study identified the thresholds, lag periods, and best indicators of extreme cold on cardiovascular disease (CVD) by comparing effects of wind chill temperatures and cold air temperatures on CVD emergency department (ED) visits in winter and winter transition months. Information was collected on 662,625 CVD ED visits from statewide hospital discharge dataset in New York State. Meteorological factors, including air temperature, wind speed, and barometric pressure were collected from National Oceanic and Atmospheric Administration. A case-crossover approach was used to assess the extreme cold-CVD relationship in winter (December-February) and transition months (November and March) after controlling for PM 2.5 . Conditional logistic regression models were employed to analyze the association between cold weather factors and CVD ED visits. We observed CVD effects occurred when wind chill temperatures were as high as -3.8 °C (25 °F), warmer than current wind chill warning standard (≤-28.8 °C or ≤-20 °F). Wind chill temperature was a more sensitive indicator of CVD ED visits during winter with temperatures ≤ -3.8 °C (25 °F) with delay effect (lag 6); however, air temperature was better during transition months for temperatures ≤ 7.2 °C (45 °F) at earlier lag days (1-3). Among all CVD subtypes, hypertension ED visit had the strongest negative association with both wind chill temperature and air temperature. This study recommends modifying the current cold warning temperature threshold given larger proportions of CVD cases are occurring at considerably higher temperatures than the current criteria. We also recommend issuing cold warnings in winter transitional months. Copyright © 2018 Elsevier B.V. All rights reserved.

Fit for high altitude: are hypoxic challenge tests useful?

PubMed

Matthys, Heinrich

2011-02-28

Altitude travel results in acute variations of barometric pressure, which induce different degrees of hypoxia, changing the gas contents in body tissues and cavities. Non ventilated air containing cavities may induce barotraumas of the lung (pneumothorax), sinuses and middle ear, with pain, vertigo and hearing loss. Commercial air planes keep their cabin pressure at an equivalent altitude of about 2,500 m. This leads to an increased respiratory drive which may also result in symptoms of emotional hyperventilation. In patients with preexisting respiratory pathology due to lung, cardiovascular, pleural, thoracic neuromuscular or obesity-related diseases (i.e. obstructive sleep apnea) an additional hypoxic stress may induce respiratory pump and/or heart failure. Clinical pre-altitude assessment must be disease-specific and it includes spirometry, pulsoximetry, ECG, pulmonary and systemic hypertension assessment. In patients with abnormal values we need, in addition, measurements of hemoglobin, pH, base excess, PaO2, and PaCO2 to evaluate whether O2- and CO2-transport is sufficient.Instead of the hypoxia altitude simulation test (HAST), which is not without danger for patients with respiratory insufficiency, we prefer primarily a hyperoxic challenge. The supplementation of normobaric O2 gives us information on the acute reversibility of the arterial hypoxemia and the reduction of ventilation and pulmonary hypertension, as well as about the efficiency of the additional O2-flow needed during altitude exposure. For difficult judgements the performance of the test in a hypobaric chamber with and without supplemental O2-breathing remains the gold standard. The increasing numbers of drugs to treat acute pulmonary hypertension due to altitude exposure (acetazolamide, dexamethasone, nifedipine, sildenafil) or to other etiologies (anticoagulants, prostanoids, phosphodiesterase-5-inhibitors, endothelin receptor antagonists) including mechanical aids to reduce periodical or insufficient ventilation during altitude exposure (added dead space, continuous or bilevel positive airway pressure, non-invasive ventilation) call for further randomized controlled trials of combined applications.

GOT C+: A Herschel Space Observatory Key Program to Study the Diffuse ISM

NASA Astrophysics Data System (ADS)

Langer, William; Velusamy, T.; Goldsmith, P. F.; Li, D.; Pineda, J.; Yorke, H.

2010-01-01

Star formation activity is regulated by pressures in the interstellar medium, which in turn depend on heating and cooling rates, modulated by the gravitational potential, and shock and turbulent pressures. To understand these processes we need information about the diffuse atomic and diffuse molecular gas cloud properties. The ionized carbon CII fine structure line at 1.9 THz is an important tracer of the atomic gas in the diffuse regions and the atomic to molecular cloud transformation. Furthermore, C+ is a major ISM coolant, the Galaxy's strongest emission line, with a total luminosity about a 1000 times that of CO J=1-0. Galactic Observations of the Terahertz C+ Line (GOT C+) is a Herschel Space Observatory Open Time Key Program to study the diffuse interstellar medium by sampling CII line emission throughout the Galactic disk. GOT C+ will obtain high spectral resolution CII using the Heterodyne Instrument for the Far Infrared (HIFI) instrument. It employees deep integrations, wide velocity coverage (350 km s-1) with 0.22 km s-1 resolution, and systematic sparse sampling of the Galactic disk together with observations of selected targets, of over 900 lines of sight. It will be a resource of the atomic gas properties, in the (a) Galactic disk, (b) Galaxy's central 300pc, (c) Galactic warp, (d) high latitude HI clouds, and (e) Photon Dominated Regions (PDRs). Along with HI, CO isotopes, and CI spectra, our C+ data will provide the astronomical community with a rich statistical database of diffuse cloud properties, for understanding the role of barometric pressure and turbulence in cloud evolution in the Galactic ISM and, by extension, other galaxies. The GOT C+ project will provide a template for future even larger-scale CII surveys. This research was conducted at the Jet Propulsion Laboratory, California Institute of Technology and is supported by a NASA grant.

GOT C+: A Herschel Space Observatory Key Program to Study the Diffuse ISM

NASA Astrophysics Data System (ADS)

Langer, William; Goldsmith, P. F.; Li, D.; Velusamy, T.; Yorke, H. W.

2009-01-01

Galactic Observations of the Terahertz C+ Line (GOT C+) is a Herschel Space Observatory (HSO) Key Program to study the diffuse interstellar medium by sampling the C+ fine structure line emission at 1.9 THz (158 microns) in the Galactic disk. Star formation activity is regulated by pressures in the interstellar medium, which in turn depend on heating and cooling rates, modulated by the gravitational potential, and shock and turbulent pressures. To understand these processes we need information about properties of the diffuse atomic and diffuse molecular gas clouds. The 158-micron CII line is an important tracer of diffuse regions, and C+ is a major ISM coolant, the Galaxy's strongest emission line virtually unobscured by dust, with a total luminosity about a 1000 times that of CO J=1-0. The GOT C+ program will obtain high spectral resolution CII spectra using the Heterodyne Instrument for the Far Infrared (HIFI) receiver. It will employ deep integrations, wide velocity coverage (350 km/s) with 0.22 km/s resolution, and systematic sparse sampling of the Galactic disk together with observations of selected targets, of over 900 lines of sight. It will be a resource to determine the properties of the atomic gas, in the (a) overall Galactic disk, (b) central 300pc of the Galactic center, (c) Galactic warp, (d) high latitude HI clouds, and (e) Photon Dominated Regions (PDRs). These spectra will provide the astronomical community with a rich statistical database of diffuse cloud properties, especially those of the atomic gas, sampled throughout the Galaxy for understanding the role of barometric pressure and turbulence in cloud evolution in the Galactic ISM and, by extension, other galaxies. The GOT C+ project will provide a template for future even larger-scale Galactic C+ surveys. This research was conducted at the Jet Propulsion Laboratory and is supported by a NASA grant.

Pushbroom Stereo for High-Speed Navigation in Cluttered Environments

DTIC Science & Technology

2014-09-01

inertial measurement sensors such as Achtelik et al .’s implemention of PTAM (parallel tracking and mapping) [15] with a barometric altimeter, stable flights...in indoor and outdoor environments are possible [1]. With a full vison- aided inertial navigation system (VINS), Li et al . have shown remarkable...avoidance on small UAVs. Stereo systems suffer from a similar speed issue, with most modern systems running at or below 30 Hz [8], [27]. Honegger et

Tropical Ocean Global Atmosphere (TOGA) Meteorological and Oceanographic Data Sets for 1985 and 1986

NASA Technical Reports Server (NTRS)

Halpern, D.; Ashby, H.; Finch, C.; Smith, E.; Robles, J.

1990-01-01

The Tropical Ocean Global Atmosphere (TOGA) Program is a component of the World Meteorological Organization (WMO)/International Council of Scientific Unions (ICSU) World Climate Research Program (WCRP). One of the objectives of TOGA, which began in 1985, is to determine the limits of predictability of monthly mean sea surface temperature variations in tropical regions. The TOGA program created a raison d'etre for an explosive growth of the tropical ocean observing system and a substantial improvement in numerical simulations from atmospheric and oceanic general circulation models. Institutions located throughout the world are involved in the TOGA-distributed active data archive system. The diverse TOGA data sets for 1985 and 1986, including results from general circulation models, are included on a CD-ROM. Variables on the CD-ROM are barometric pressure, surface air temperature, dewpoint temperature Cartesian components of surface wind, surface sensible and latent heat fluxes,Cartesian components of surface wind stress and of an index of surface wind stress, sea level, sea surface temperature, and depth profiles of temperature and current in the upper ocean. Some data sets are global in extent, some are regional and cover portions of an ocean basin. Data on the CD-ROM can be extracted with an Apple Macintosh or an IBM PC.

Geohydrologic data from Port Royal Sound, Beaufort County, South Carolina

USGS Publications Warehouse

Burt, R.A.; Belval, D.L.; Crouch, Michael; Hughes, W.B.

1986-01-01

Nine offshore wells were drilled through overlying sediments into the Upper Floridan aquifer in Port Royal Sound, South Carolina and the adjacent Atlantic Ocean, to obtain geologic, hydrologic, and water quality data. The Upper Floridan aquifer consists predominantly of light-gray, poorly consolidated, fossiliferous limestone. In the Port Royal Sound area, the Upper Floridan is overlain by olive-gray, medium to course sand and silty sand. Falling-head permeability tests on these overlying clastic sediments indicate permeabilities of 1,100 to 4.3 x 10 to the 7th power centimeters/sec. Other geologic and hydrologic data, including geophysical logs, sieve analyses, and detailed core descriptions were obtained, along with continuous water level records of the wells, tidal records, and barometric pressure records. Water collected from the Upper Floridan aquifer beneath Port Royal Sound and the ocean ranged in concentration of chloride from 54 to 12,000 mg/l. Measured pH ranged from 6.8 to 8.4, and alkalinity ranged from 122 to 368 mg/l as CaC03. Other water quality data obtained include temperature, specific conductance, carbon-13, carbon-14, tritium , deuterium, oxygen-18, dissolved oxygen, dissolved solids, nitrogen species, phosphorus, organic carbon, cyanide, sulfide, calcium, magnesium, sodium, potassium, sulfate, fluoride, silica , bromide, iodide, and selected trace metals. (USGS)

Use of time series and harmonic constituents of tidal propagation to enhance estimation of coastal aquifer heterogeneity

USGS Publications Warehouse

Hughes, Joseph D.; White, Jeremy T.; Langevin, Christian D.

2010-01-01

A synthetic two‐dimensional model of a horizontally and vertically heterogeneous confined coastal aquifer system, based on the Upper Floridan aquifer in south Florida, USA, subjected to constant recharge and a complex tidal signal was used to generate 15‐minute water‐level data at select locations over a 7‐day simulation period.   “Observed” water‐level data were generated by adding noise, representative of typical barometric pressure variations and measurement errors, to 15‐minute data from the synthetic model. Permeability was calibrated using a non‐linear gradient‐based parameter inversion approach with preferred‐value Tikhonov regularization and 1) “observed” water‐level data, 2) harmonic constituent data, or 3) a combination of “observed” water‐level and harmonic constituent data.    In all cases, high‐frequency data used in the parameter inversion process were able to characterize broad‐scale heterogeneities; the ability to discern fine‐scale heterogeneity was greater when harmonic constituent data were used.  These results suggest that the combined use of highly parameterized‐inversion techniques and high frequency time and/or processed‐harmonic constituent water‐level data could be a useful approach to better characterize aquifer heterogeneities in coastal aquifers influenced by ocean tides.

Limited denitrification in glacial deposit aquifers having thick unsaturated zones (Long Island, USA)

NASA Astrophysics Data System (ADS)

Young, Caitlin; Kroeger, Kevin D.; Hanson, Gilbert

2013-12-01

The goal of this study was to demonstrate how the extent of denitrification, which is indirectly related to dissolved organ carbon and directly related to oxygen concentrations, can also be linked to unsaturated-zone thickness, a mappable aquifer property. Groundwater from public supply and monitoring wells in Northport on Long Island, New York state (USA), were analyzed for denitrification reaction progress using dissolved N2/Ar concentrations by membrane inlet mass spectrometry. This technique allows for discernment of small amounts of excess N2, attributable to denitrification. Results show an average 15 % of total nitrogen in the system was denitrified, significantly lower than model predictions of 35 % denitrification. The minimal denitrification is due to low dissolved organic carbon (29.3-41.1 μmol L-1) and high dissolved oxygen concentrations (58-100 % oxygen saturation) in glacial sediments with minimal solid-phase electron donors to drive denitrification. A mechanism is proposed that combines two known processes for aquifer re-aeration in unconsolidated sands with thick (>10 m) unsaturated zones. First, advective flux provides 50 % freshening of pore space oxygen in the upper 2 m due to barometric pressure changes. Then, oxygen diffusion across the water-table boundary occurs due to high volumetric air content in the unsaturated-zone catchment area.

Two Long-Term Instrumental Climatic Data Bases of the People's Republic of China (1997)

DOE Data Explorer

Shiyan, T. [Chinese Academy of Sciences (CAS), Beijing (China); Congbin, Fu [Chinese Academy of Sciences (CAS), Beijing (China); Zhaomei, Zeng [Chinese Academy of Sciences (CAS), Beijing (China); Qingyun, Zhang [Chinese Academy of Sciences (CAS), Beijing (China); Kaiser, D. P.

1991-01-01

Two long-term instrumental data bases containing meteorological observations from the People's Republic of China (PRC) are presented in this NDP . The first version of this database was made available in 1991 by the Carbon Dioxide Information Analysis Center (CDIAC) as CDIAC NDP-039. This update of the database includes data through 1993. These data sets were compiled in accordance with a joint research agreement signed by the U.S. Department of Energy and the PRC Chinese Academy of Sciences (CAS) on August 19, 1987. CAS has provided records from 267 stations, partitioned into two networks of 65 and 205 stations, with three stations common to both data bases. The 65-station-network data contain monthly means, extremes, or totals of barometric pressure, air temperature, precipitation amount, relative humidity, sunshine duration, cloud amount, dominant wind direction and frequency, wind speed, and number of days with snow cover. Station histories are available from 59 of the 65 stations. The 205-station-network data contain monthly mean temperatures and monthly precipitation totals; however, station histories are not currently available. Sixteen stations from these data sets (13 from the 65-station, 3 from the 205-station) have temperature and/or precipitation records beginning before 1900, whereas the remaining stations began observing in the early to mid-1900s.

Decoding magma plumbing and geochemical evolution beneath the Lastarria volcanic complex (Northern Chile)-Evidence for multiple magma storage regions

NASA Astrophysics Data System (ADS)

Stechern, André; Just, Tobias; Holtz, François; Blume-Oeste, Magdalena; Namur, Olivier

2017-05-01

The petrology of quaternary andesites and dacites from Lastarria volcano was investigated to reconstruct the magma plumbing and storage conditions beneath the volcano. The mineral phase compositions and whole-rock major and trace element compositions were used to constrain temperature, pressure and possible mechanisms for magma differentiation. The applied thermobarometric models include two-pyroxene thermobarometry, plagioclase-melt thermometry, amphibole composition thermobarometry, and Fe-Ti oxide thermo-oxybarometry. The overall temperature estimation is in the range 840 °C to 1060 °C. Calculated oxygen fugacity ranges between NNO to NNO + 1. Results of the geo-barometric calculations reveal multiple magma storage regions, with a distinct storage level in the uppermost crust ( 6.5-8 km depth), a broad zone at mid-crustal levels ( 10-18 km depth), and a likely deeper zone at intermediate to lower crustal levels (> 20 km depth). The highest temperatures in the range 940-1040 °C are recorded in minerals stored in the mid-crustal levels ( 10-18 km depth). The whole-rock compositions clearly indicate that magma mixing is the main parameter controlling the general differentiation trends. Complex zoning patterns and textures in the plagioclase phenocrysts confirm reheating and remobilization processes due to magma replenishment.

Relationship between Acute Phase of Chronic Periodontitis and Meteorological Factors in the Maintenance Phase of Periodontal Treatment: A Pilot Study.

PubMed

Takeuchi, Noriko; Ekuni, Daisuke; Tomofuji, Takaaki; Morita, Manabu

2015-08-05

The acute phase of chronic periodontitis may occur even in patients during supportive periodontal therapy. However, the details are not fully understood. Since the natural environment, including meteorology affects human health, we hypothesized that weather conditions may affect occurrence of acute phase of chronic periodontitis. The aim of this study was to investigate the relationship between weather conditions and acute phase of chronic periodontitis in patients under supportive periodontal therapy. Patients who were diagnosed with acute phase of chronic periodontitis under supportive periodontal therapy during 2011-2013 were selected for this study. We performed oral examinations and collected questionnaires and meteorological data. Of 369 patients who experienced acute phase of chronic periodontitis, 153 had acute phase of chronic periodontitis without direct-triggered episodes. When using the autoregressive integrated moving average model of time-series analysis, the independent covariant of maximum hourly range of barometric pressure, maximum hourly range of temperature, and maximum daily wind speed were significantly associated with occurrence of acute phase of chronic periodontitis (p < 0.05), and 3.1% of the variations in these occurrence over the study period were explained by these factors. Meteorological variables may predict occurrence of acute phase of chronic periodontitis.

Data mining on long-term barometric data within the ARISE2 project

NASA Astrophysics Data System (ADS)

Hupe, Patrick; Ceranna, Lars; Pilger, Christoph

2016-04-01

The Comprehensive nuclear-Test-Ban Treaty (CTBT) led to the implementation of an international infrasound array network. The International Monitoring System (IMS) network includes 48 certified stations, each providing data for up to 15 years. As part of work package 3 of the ARISE2 project (Atmospheric dynamics Research InfraStructure in Europe, phase 2) the data sets will be statistically evaluated with regard on atmospheric dynamics. The current study focusses on fluctuations of absolute air pressure. Time series have been analysed for 17 monitoring stations which are located all over the world between Greenland and Antarctica along the latitudes to represent different climate zones and characteristic atmospheric conditions. Hence this enables quantitative comparisons between those regions. Analyses are shown including wavelet power spectra, multi-annual time series of average variances with regard to long-wave scales, and spectral densities to derive characteristics and special events. Evaluations reveal periodicities in average variances on 2 to 20 day scale with a maximum in the winter months and a minimum in summer of the respective hemisphere. This basically applies to time series of IMS stations beyond the tropics where the dominance of cyclones and anticyclones changes with seasons. Furthermore, spectral density analyses illustrate striking signals for several dynamic activities within one day, e.g., the semidiurnal tide.

Binary vapor cycle method of electrical power generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Humiston, G.F.

1982-04-13

A binary vapor cycle method of electrical power generation is disclosed wherein two refrigerant fluids can be used to operate an apparatus for the generation of mechanical power as well as electrical power generation. This method, which is essentially a dual heat pump system, offers an approach to utilizing the advantages of two different refrigerants within a single apparatus. This advantage is particularly advantageous in the ulitization of low specific energy sources, such as two water sources which exist in close proximity to each other, but at different temperatures. Thus, water, which itself is a heat pump fluid, can bemore » used as a means of transmitting heat energy to a second heat pump fluid, or refrigerant, without incurring the disadvantages of water, or water vapors, as a means to produce power, because of its high specific volume and low saturation pressures at low temperatures. Additionally, since the warm water source of energy most commonly available is in the form of reservoirs, such as the ocean waters, and the utilization of barometric legs to bring the warm water into contact with the process, eliminates the use of expensive heat exchangers, which is the case of ocean water, are subject to fouling and loss of efficiency due to clinging microorganisms.« less

Single-Grasp Object Classification and Feature Extraction with Simple Robot Hands and Tactile Sensors.

PubMed

Spiers, Adam J; Liarokapis, Minas V; Calli, Berk; Dollar, Aaron M

2016-01-01

Classical robotic approaches to tactile object identification often involve rigid mechanical grippers, dense sensor arrays, and exploratory procedures (EPs). Though EPs are a natural method for humans to acquire object information, evidence also exists for meaningful tactile property inference from brief, non-exploratory motions (a 'haptic glance'). In this work, we implement tactile object identification and feature extraction techniques on data acquired during a single, unplanned grasp with a simple, underactuated robot hand equipped with inexpensive barometric pressure sensors. Our methodology utilizes two cooperating schemes based on an advanced machine learning technique (random forests) and parametric methods that estimate object properties. The available data is limited to actuator positions (one per two link finger) and force sensors values (eight per finger). The schemes are able to work both independently and collaboratively, depending on the task scenario. When collaborating, the results of each method contribute to the other, improving the overall result in a synergistic fashion. Unlike prior work, the proposed approach does not require object exploration, re-grasping, grasp-release, or force modulation and works for arbitrary object start positions and orientations. Due to these factors, the technique may be integrated into practical robotic grasping scenarios without adding time or manipulation overheads.

Air transport of patients with pneumothorax: is tube thoracostomy required before flight?

PubMed

Braude, Darren; Tutera, Dominic; Tawil, Issac; Pirkl, Gregory

2014-01-01

It is conventionally thought that patients with pneumothorax (PTX) require tube thoracostomy (TT) before air medical transport (AMT), especially in unpressurized rotor-wing (RW) aircraft, to prevent deterioration from expansion of the PTX or development of tension PTX. We hypothesize that patients with PTX transported without TT tolerate RW AMT without serious deterioration, as defined by hypotension, hypoxemia, respiratory distress, intubation, bag valve mask ventilation, needle thoracostomy (NT), or cardiac arrest during transport. We conducted a retrospective review of a case-series of trauma patients transported to a single Level 1 trauma center via RW with confirmed PTX and no TT. Using standardized abstraction forms, we reviewed charts for signs of deterioration. Those patients identified as having clinical deterioration were independently reviewed for the likelihood that the clinical deterioration was a direct consequence of PTX. During the study period, 66 patients with confirmed PTX underwent RW AMT with an average altitude gain of 1890 feet, an average barometric pressure 586-600 mmHg, and average flight duration of 28 minutes. All patients received oxygen therapy; 14/66 patients (21%) were supported with positive pressure ventilation. Eleven of 66 patients (17%) had NT placed before flight and 4/66 (6%) had NT placed during flight. Four of 66 patients (6% CI0.3-11.7) may have deteriorated during AMT as a result of PTX; all were successfully managed with NT. In this series, 6% of patients with PTX deteriorated as result of AMT without TT, yet all patients were managed successfully with NT. Routine placement of TT in patients with PTX before RW AMT may not be necessary. Further prospective evaluation is warranted. Copyright © 2014 Air Medical Journal Associates. Published by Elsevier Inc. All rights reserved.

Barosinusitis: Comprehensive review and proposed new classification system

PubMed Central

Vaezeafshar, Reza; Psaltis, Alkis J.; Rao, Vidya K.; Zarabanda, David; Patel, Zara M.

2017-01-01

Background: Barosinusitis, or sinus barotrauma, may arise from changes in ambient pressure that are not compensated by force equalization mechanisms within the paranasal sinuses. Barosinusitis is most commonly seen with barometric changes during flight or diving. Understanding and better classifying the pathophysiology, clinical presentation, and management of barosinusitis are essential to improve patient care. Objectives: To perform a comprehensive review of the available literature regarding sinus barotrauma. Methods: A comprehensive literature search that used the terms “barosinusitis,” “sinus barotrauma,” and “aerosinusitis” was conducted, and all identified titles were reviewed for relevance to the upper airway and paranasal sinuses. All case reports, series, and review articles that were identified from this search were included. Selected cases of sinus barotrauma from our institution were included to illustrate classic signs and symptoms. Results: Fifty-one articles were identified as specifically relevant to, or referencing, barosinusitis and were incorporated into this review. The majority of articles focused on barosinusitis in the context of a single specific etiology rather than independent of etiology. From analysis of all the publications combined with clinical experience, we proposed that barosinusitis seemed to fall within three distinct subtypes: (1) acute, isolated barosinusitis; (2) recurrent acute barosinusitis; and (3) chronic barosinusitis. We introduced this terminology and suggested independent treatment recommendations for each subtype. Conclusion: Barosinusitis is a common but potentially overlooked condition that is primed by shifts in the ambient pressure within the paranasal sinuses. The pathophysiology of barosinusitis has disparate causes, which likely contribute to its misdiagnosis and underdiagnosis. Available literature compelled our proposed modifications to existing classification schemes, which may allow for improved awareness and management strategies for barosinusitis. PMID:29070267

[Definition and validation of a comfort index calculation method for office seats].

PubMed

Taboga, P; Marcolin, F; Bordignon, M; Antonutto, G

2012-01-01

Among its other required features, a highly comfortable chair should adapt its contact surfaces, namely the seat and the back rest, to the shape of the body of the person sitting on it. However, "comfort" is not usually perceived as an absolute value, but is derived from a subjective comparison between two or more chairs. The purpose of this research was the definition of an objective comfort index (IC), i.e., derived from instrumental measurements, and which would also represent an absolute comfort value. Analytical evaluation of the distribution of body weight, by means of a barometric matrix, shows that a comfortable chair tends to minimize peak and average values of pressure at the level of the contact areas located between the body and the seat and the back of the chair. To define a comparison parameter for determining an absolute comfort value, a reference chair (SDR) was developed. The seat and the back of this chair are rigid, with poor compliance. A comfort value of zero was, by definition, assigned to this chair. Therefore, the Comfort index (IC) was obtained by the mathematical calculation of the ratios of averages, peaks and gradients of pressure, appropriately weighted, and the corresponding values measured on the tested chair and on the SDR. It is shown that the anthropometric characteristics of each subject are irrelevant to the assessment of the IC, which depends only on the compliance characteristics of the seat and back surfaces of the tested chair IC can be improved through analysis of a larger number of seats, which would thus constitute the basis for the use of an objective evaluation of seating comfort.

Results from Geothermal Logging, Air and Core-Water Chemistry Sampling, Air Injection Testing and Tracer Testing in the Northern Ghost Dance Fault, YUCCA Mountain, Nevada, November 1996 to August 1998

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lecain, G.D.; Anna, L.O.; Fahy, M.F.

1998-08-01

Geothermal logging, air and core-water chemistry sampling, air-injection testing, and tracer testing were done in the northern Ghost Dance Fault at Yucca Mountain, Nevada, from November 1996 to August 1998. The study was done by the U.S. Geological Survey, in cooperation with the U.S. Department of Energy. The fault-testing drill room and test boreholes were located in the crystal-poor, middle nonlithophysal zone of the Topopah Spring Tuff, a tuff deposit of Miocene age. The drill room is located off the Yucca Mountain underground Exploratory Studies Facility at about 230 meters below ground surface. Borehole geothermal logging identified a temperature decreasemore » of 0.1 degree Celsius near the Ghost Dance Fault. The temperature decrease could indicate movement of cooler air or water, or both, down the fault, or it may be due to drilling-induced evaporative or adiabatic cooling. In-situ pneumatic pressure monitoring indicated that barometric pressure changes were transmitted from the ground surface to depth through the Ghost Dance Fault. Values of carbon dioxide and delta carbon-13 from gas samples indicated that air from the underground drill room had penetrated the tuff, supporting the concept of a well-developed fracture system. Uncorrected carbon-14-age estimates from gas samples ranged from 2,400 to 4,500 years. Tritium levels in borehole core water indicated that the fault may have been a conduit for the transport of water from the ground surface to depth during the last 100 years.« less

Biosphere 2 test module: A ground-based sunlight-driven prototype of a closed ecological life support system

NASA Astrophysics Data System (ADS)

Nelson, Mark; Leigh, Linda; Alling, Abigail; MacCallum, Taber; Allen, John; Alvarez-Romo, Norberto

Constructed in 1986, the Biosphere 2 Test Module has been used since the end of that year for closed ecological systems experiments. It is the largest closed ecological facility ever built, with a sealed variable volume of some 480 cubic meters. It is built with a skin of steel spaceframes with double-laminated glass panels admitting about 65 percent Photosynthetically Active Radiation (PAR). The floor is of welded steel and there is an underground atmospheric connection via an air duct to a variable volume chamber (``lung'') permitting expansion and contraction of the Test Module's air volume caused by changes in temperature and barometric pressure, which causes a slight positive pressure from inside the closed system to the outside thereby insuring that the very small leakage rate is outward. Several series of closed ecological system investigations have been carried out in this facility. One series of experiments investigated the dynamics of higher plants and associated soils with the atmosphere under varying light and temperature conditions. Another series of experiments included one human in the closed system for three, five and twenty-one days. During these experiments the Test Module had subsystems which completely recycled its water and atmosphere; all the human dietary needs were produced within the facility, and all wastes were recycled using a marsh plant/microbe system. Other experiments have examined the capability of individual component systems used, such as the soil bed reactors, to eliminate experimentally introduced trace gases. Analytic systems developed for these experiments include continuous monitors of eleven atmospheric gases in addition to the complete gas chromatography mass spectrometry (GCMS) examinations of potable, waste system and irrigation water quality.

Patterns of entrapped air dissolution in a two-dimensional pilot-scale synthetic aquifer.

PubMed

McLeod, Heather C; Roy, James W; Smith, James E

2015-01-01

Past studies of entrapped air dissolution have focused on one-dimensional laboratory columns. Here the multidimensional nature of entrapped air dissolution was investigated using an indoor tank (180 × 240 × 600 cm(3) ) simulating an unconfined sand aquifer with horizontal flow. Time domain reflectometry (TDR) probes directly measured entrapped air contents, while dissolved gas conditions were monitored with total dissolved gas pressure (PTDG ) probes. Dissolution occurred as a diffuse wedge-shaped front from the inlet downgradient, with preferential dissolution at depth. This pattern was mainly attributed to increased gas solubility, as shown by PTDG measurements. However, compression of entrapped air at greater depths, captured by TDR and leading to lower quasi-saturated hydraulic conductivities and thus greater velocities, also played a small role. Linear propagation of the dissolution front downgradient was observed at each depth, with both TDR and PTDG , with increasing rates with depth (e.g, 4.1 to 5.7× slower at 15 cm vs. 165 cm depth). PTDG values revealed equilibrium with the entrapped gas initially, being higher at greater depth and fluctuating with the barometric pressure, before declining concurrently with entrapped air contents to the lower PTDG of the source water. The observed dissolution pattern has long-term implications for a wide variety of groundwater management issues, from recharge to contaminant transport and remediation strategies, due to the persistence of entrapped air near the water table (potential timescale of years). This study also demonstrated the utility of PTDG probes for simple in situ measurements to detect entrapped air and monitor its dissolution. © 2014 Her Majesty the Queen in Right of Canada Groundwater © 2014, National Ground Water Association.

Performance Analysis of Automatic Dependent Surveillance-Broadcast (ADS-B) and Breakdown of Anomalies

NASA Astrophysics Data System (ADS)

Tabassum, Asma

This thesis work analyzes the performance of Automatic Dependent Surveillance-Broadcast (ADS-B) data received from Grand Forks International Airport, detects anomalies in the data and quantifies the associated potential risk. This work also assesses severity associated anomalous data in Detect and Avoid (DAA) for Unmanned Aircraft System (UAS). The received data were raw and archived in GDL-90 format. A python module is developed to parse the raw data into readable data in a .csv file. The anomaly detection algorithm is based on Federal Aviation Administration's (FAA) ADS-B performance assessment report. An extensive study is carried out on two main types of anomalies, namely dropouts and altitude deviations. A dropout is considered when the update rate exceeds three seconds. Dropouts are of different durations and have a different level of risk depending on how much time ADS-B is unavailable as the surveillance system. Altitude deviation refers to the deviation between barometric and geometric altitude. Deviation ranges from 25 feet to 600 feet have been observed. As of now, barometric altitude has been used for separation and surveillance while geometric altitude can be used in cases where barometric altitude is not available. Many UAS might not have both sensors installed on board due to size and weight constrains. There might be a chance of misinterpretation of vertical separation specially while flying in National Airspace (NAS) if the ownship UAS and intruder manned aircraft use two different altitude sources for separation standard. The characteristics and agreement between two different altitudes is investigated with a regression based approach. Multiple risk matrices are established based on the severity of the DAA well clear. ADS-B is called the Backbone of FAA Next Generation Air Transportation System, NextGen. NextGen is the series of inter-linked programs, systems, and policies that implement advanced technologies and capabilities. ADS-B utilizes the Satellite based Global Positioning System (GPS) technology to provide the pilot and the Air Traffic Control (ATC) with more information which enables an efficient navigation of aircraft in increasingly congested airspace. FAA mandated all aircraft, both manned and unmanned, be equipped with ADS-B out by the year 2020 to fly within most controlled airspace. As a fundamental component of NextGen it is crucial to understand the behavior and potential risk with ADS-B Systems.

Visualizing Data from EarthScope's USArray

NASA Astrophysics Data System (ADS)

Woodward, R.; Frassetto, A.; Adinolfi, A.

2012-12-01

The EarthScope USArray program has generated a large volume of data from across the North American continent. The Transportable Array (TA) component of USArray has deployed over 400 seismic stations in a grid with 70 km spacing between stations. The TA has rolled the array across the contiguous US states over a ten-year period, and will have occupied over 1600 distinct sites from the Pacific Ocean to the Atlantic Ocean by the end of 2013. All stations transmit multiple channels of 40 samples per second data continuously, in near real time. Each station records and transmits seismic, barometric pressure, and infrasound data, as well as various state-of-health data streams. All data are immediately open and unrestricted. The TA provides a unique tool for visualizing large-scale seismic wave phenomena. The power of this tool is particularly apparent when displaying simultaneous signals from all stations as a function of time, as well as rendering multiple channels of data from each station. In this situation it is challenging to convey the 3D motion at each station as well as the aggregate 3D motion across the entire set of 400 stations. Creating movies of the data becomes essential to illustrate the time dependence of the observations. Typically the rendering of such movies requires the use of programming language that is suitable for both data analysis and graphics, as it is essential to explore different data pre-processing strategies (often filtering, but also including other pre-processing steps). Different visualization strategies provide a means for dealing with the very large volume of data generated by the TA. Typical data review strategies include a survey mode to scan large volumes of data for signals of interest, or zooming in on fine features using combinations of specialized data processing and frame-by-frame time-steps, or going back and forth between the two modes. The data visualizations are continuously evolving to explore new ideas. The movie-based representations of the data also provide an excellent medium for education and outreach. Complex wave phenomena become immediately visible to both the trained and untrained eye. Yet there are challenges in conveying an understanding of how the output of a single sensor relates to the output of multiple sensors, and how color variations are used to represent at least one of the dimensions. Conventions that are common to a scientific audience may not be familiar to other audiences. We have explored strategies for trying to add a perspective view and a sense of spatial orientation to the visualizations to make them more useful in educational settings. Some of these visualizations are now routinely produced as data products to support research and education. We will provide examples of the visualization results, including movies of seismic surface waves spreading out on the planet and the use of perspective views, cross-sections, contours, and other graphical techniques as a means to gain insight into the data. We will also provide examples of the time and spatial evolution of barometric pressure variations, seismic background noise, and solar irradiance. Examples of data visualizations created for both specialists and non-specialists will be included.

Monitoring storm tide and flooding from Hurricane Isaac along the Gulf Coast of the United States, August 2012

USGS Publications Warehouse

McCallum, Brian E.; McGee, Benton D.; Kimbrow, Dustin R.; Runner, Michael S.; Painter, Jaime A.; Frantz, Eric R.; Gotvald, Anthony J.

2012-01-01

The U.S. Geological Survey (USGS) deployed a temporary monitoring network of water-level and barometric pressure sensors at 127 locations along the gulf coast from Alabama to Louisiana to record the timing, areal extent, and magnitude of hurricane storm tide and coastal flooding generated by Hurricane Isaac. This deployment was undertaken as part of a coordinated federal emergency response as outlined by the Stafford Act under a directed mission assignment by the Federal Emergency Management Agency. Storm tide, as defined by National Oceanic and Atmospheric Administration (NOAA; National Oceanic and Atmospheric Administration, 2008), is the water-level rise generated by a combination of storm surge and astronomical tide during a coastal storm. Hurricane Isaac initially made landfall on the coast of Louisiana in Plaquemines Parish on August 28, 2012, as a Category 1 hurricane on the Saffir–Simpson Hurricane Wind Scale (National Weather Service, 1974) and then stalled over southern Louisiana for several days, causing prolonged storm-tide impacts. A total of 188 water-level and wave-height sensors were deployed at 127 locations during August 27–28 prior to landfall. More than 90 percent of the sensors and all high-water marks (HWMs) were recovered and surveyed to North American Vertical Datum of 1988 (NAVD 88) within 7 days of the Isaac landfall. Only a handful of sensors in the Plaquemines Parish area of Louisiana could not be retrieved until weeks later due to prolonged flooding in the area. Data collected from this event can be used to evaluate the performance of storm-tide models for maximum and incremental water level and flood extent and the site-specific effects of storm tide on natural and anthropogenic features of the environment.

Supplemental oxygen effect on hypoxemia at moderate altitude in patients with COPD.

PubMed

Kelly, Paul T; Swanney, Maureen P; Stanton, Josh D; Frampton, Chris; Peters, Matthew J; Beckert, Lutz E

2009-09-01

Altitude exposure will cause moderate to severe hypoxemia in patients with chronic obstructive pulmonary disease (COPD). Supplemental oxygen can be used to attenuate this hypoxemia; however, individual response is variable and difficult to predict. The aim of this study was to assess the efficacy of oxygen supplementation in patients with COPD at a barometric pressure similar to that of a commercial aircraft cabin. Following sea-level (40 m) arterial blood gases measurements, 18 patients with COPD were driven to altitude (2086 m), where blood gases were repeated at rest and while on 2 L x min(-1) of supplementary oxygen (altitude O2). Ascent from sea level to altitude caused significant hypoxemia (75 +/- 9 vs. 51 +/- 6 mmHg), which was partially reversed by supplemental oxygen (64 +/- 9 mmHg). Oxygen supplementation did not significantly alter PaCO2 levels (vs. altitude PaCO2). There was a significant relationship between the sea-level CaO2 versus the altitude O2 CaO2 (r = 0.89, P < 0.001). There was a significant relationship (r = 0.81, P < 0.001) between altitude-induced desaturation and resaturation with the administration of oxygen. There was a significant negative correlation (r = -0.74, P < 0.001) between baseline K(CO) and the improvement in CaO2 with the administration of oxygen. Low-flow supplemental oxygen during acute altitude exposure will partially reverse altitude-induced hypoxemia in patients with COPD. Patients with diffusion impairments are likely to experience the greatest altitude desaturation, but will gain the most benefit from supplemental oxygen. Supplemental oxygen, delivered at 2 L x min(-1), should maintain clinically acceptable oxygenation during commercial air travel in patients with COPD.

Impact of weather factors on hand, foot and mouth disease, and its role in short-term incidence trend forecast in Huainan City, Anhui Province.

PubMed

Zhao, Desheng; Wang, Lulu; Cheng, Jian; Xu, Jun; Xu, Zhiwei; Xie, Mingyu; Yang, Huihui; Li, Kesheng; Wen, Lingying; Wang, Xu; Zhang, Heng; Wang, Shusi; Su, Hong

2017-03-01

Hand, foot, and mouth disease (HFMD) is one of the most common communicable diseases in China, and current climate change had been recognized as a significant contributor. Nevertheless, no reliable models have been put forward to predict the dynamics of HFMD cases based on short-term weather variations. The present study aimed to examine the association between weather factors and HFMD, and to explore the accuracy of seasonal auto-regressive integrated moving average (SARIMA) model with local weather conditions in forecasting HFMD. Weather and HFMD data from 2009 to 2014 in Huainan, China, were used. Poisson regression model combined with a distributed lag non-linear model (DLNM) was applied to examine the relationship between weather factors and HFMD. The forecasting model for HFMD was performed by using the SARIMA model. The results showed that temperature rise was significantly associated with an elevated risk of HFMD. Yet, no correlations between relative humidity, barometric pressure and rainfall, and HFMD were observed. SARIMA models with temperature variable fitted HFMD data better than the model without it (sR 2 increased, while the BIC decreased), and the SARIMA (0, 1, 1)(0, 1, 0) 52 offered the best fit for HFMD data. In addition, compared with females and nursery children, males and scattered children may be more suitable for using SARIMA model to predict the number of HFMD cases and it has high precision. In conclusion, high temperature could increase the risk of contracting HFMD. SARIMA model with temperature variable can effectively improve its forecast accuracy, which can provide valuable information for the policy makers and public health to construct a best-fitting model and optimize HFMD prevention.

Impact of weather factors on hand, foot and mouth disease, and its role in short-term incidence trend forecast in Huainan City, Anhui Province

NASA Astrophysics Data System (ADS)

Zhao, Desheng; Wang, Lulu; Cheng, Jian; Xu, Jun; Xu, Zhiwei; Xie, Mingyu; Yang, Huihui; Li, Kesheng; Wen, Lingying; Wang, Xu; Zhang, Heng; Wang, Shusi; Su, Hong

2017-03-01

Hand, foot, and mouth disease (HFMD) is one of the most common communicable diseases in China, and current climate change had been recognized as a significant contributor. Nevertheless, no reliable models have been put forward to predict the dynamics of HFMD cases based on short-term weather variations. The present study aimed to examine the association between weather factors and HFMD, and to explore the accuracy of seasonal auto-regressive integrated moving average (SARIMA) model with local weather conditions in forecasting HFMD. Weather and HFMD data from 2009 to 2014 in Huainan, China, were used. Poisson regression model combined with a distributed lag non-linear model (DLNM) was applied to examine the relationship between weather factors and HFMD. The forecasting model for HFMD was performed by using the SARIMA model. The results showed that temperature rise was significantly associated with an elevated risk of HFMD. Yet, no correlations between relative humidity, barometric pressure and rainfall, and HFMD were observed. SARIMA models with temperature variable fitted HFMD data better than the model without it (s R 2 increased, while the BIC decreased), and the SARIMA (0, 1, 1)(0, 1, 0)52 offered the best fit for HFMD data. In addition, compared with females and nursery children, males and scattered children may be more suitable for using SARIMA model to predict the number of HFMD cases and it has high precision. In conclusion, high temperature could increase the risk of contracting HFMD. SARIMA model with temperature variable can effectively improve its forecast accuracy, which can provide valuable information for the policy makers and public health to construct a best-fitting model and optimize HFMD prevention.

Increase in slow-wave vasomotion by hypoxia and ischemia in lowlanders and highlanders.

PubMed

Salvi, Paolo; Faini, Andrea; Castiglioni, Paolo; Brunacci, Fausto; Montaguti, Luca; Severi, Francesca; Gautier, Sylvie; Pretolani, Enzo; Benetos, Athanase; Parati, Gianfranco

2018-06-21

The physiological relevance of slow-wave vasomotion is still unclear, even it has been hypothesized it could be a compensatory mechanism enhancing tissue oxygenation in conditions of reduced oxygen supply. Aim of our study was to explore the effects of hypoxia and ischemia on slow-wave vasomotion in microcirculation. Peripheral oxygen saturation and forearm microcirculation flow (laser-Doppler flowmetry) were recorded at baseline and during post-occlusive reactive hyperemia in the Himalaya region from 8 European lowlanders (6 males; aged 29-39yrs) at 1350, 3400 and 5050m, and from 10 Nepalese male highlanders (aged 21-39yrs) at 3400 and 5050m of altitude. The same measurements were also performed at sea level in 16 healthy volunteers (aged 23-61yrs) during a short-term exposure to normobaric hypoxia. In lowlanders, exposure to progressively higher altitude under baseline flow conditions progressively increased 0.06-0.15Hz vasomotion amplitude [power spectral density % expressed as geometric means (geometric standard deviation) =14.0(3.6) at 1350m; 87.0(2.3) at 3400m and 249.8(3.6) at 5050m, p=0.006 and p<0.001 vs 1350m, respectively]. In highlanders, low frequency vasomotion amplitude was similarly enhanced at different altitudes [power spectral density % =183.4(4.1) at 3400m vs 236.0(3.0) at 5050m, p=0.139]. In both groups at altitude it was further increased after ischemic stimulus (p<0.001). At baseline, acute short lasting normobaric hypoxia did not induce low frequency vasomotion, which was conversely induced by ischemia even under normal oxygenation and barometric pressure. This study offers the demonstration of a significant increase in slow-wave vasomotion under prolonged hypobaric-hypoxia exposure at high altitude, with a further enhancement after ischemia induction.

Water level and strain changes preceding and following the August 4, 1985 Kettleman Hills, California, earthquake

USGS Publications Warehouse

Roeloffs, E.; Quilty, E.

1997-01-01

Two of the four wells monitored near Parkfield, California, during 1985 showed water level rises beginning three days before the M4 6.1 Kettleman Hills earthquake. In one of these wells, the 3.0 cm rise was nearly unique in five years of water level data. However, in the other well, which showed a 3.8 cm rise, many other changes of comparable size have been observed. Both wells that did not display pre-earthquake rises tap partially confined aquifers that cannot sustain pressure changes due to tectonic strain having periods longer than several days. We evaluate the effect of partial aquifer confinement on the ability of these four wells to display water level changes in response to aquifer strain. Although the vertical hydraulic diffusivities cannot be determined uniquely, we can find a value of diffusivity for each site that is consistent with the site's tidal and barometric responses as well as with the rate of partial recovery of the coseismic water level drops. Furthermore, the diffusivity for one well is high enough to explain why the preseismic rise could not have been detected there. For the fourth well, the diffusivity is high enough to have reduced the size of the preseismic signal as much as 50%, although it should still have been detectable. Imperfect confinement cannot explain the persistent water level changes in the two partially confined aquifers, but it does show that they were not due to volume strain. The pre-earthquake water level rises may have been precursors to the Kettleman Hills earthquake. If so, they probably were not caused by accelerating slip over the part of the fault plane that ruptured in that earthquake because they are of opposite sign to the observed coseismic water level drops.

The ambient dose equivalent at flight altitudes: a fit to a large set of data using a Bayesian approach.

PubMed

Wissmann, F; Reginatto, M; Möller, T

2010-09-01

The problem of finding a simple, generally applicable description of worldwide measured ambient dose equivalent rates at aviation altitudes between 8 and 12 km is difficult to solve due to the large variety of functional forms and parametrisations that are possible. We present an approach that uses Bayesian statistics and Monte Carlo methods to fit mathematical models to a large set of data and to compare the different models. About 2500 data points measured in the periods 1997-1999 and 2003-2006 were used. Since the data cover wide ranges of barometric altitude, vertical cut-off rigidity and phases in the solar cycle 23, we developed functions which depend on these three variables. Whereas the dependence on the vertical cut-off rigidity is described by an exponential, the dependences on barometric altitude and solar activity may be approximated by linear functions in the ranges under consideration. Therefore, a simple Taylor expansion was used to define different models and to investigate the relevance of the different expansion coefficients. With the method presented here, it is possible to obtain probability distributions for each expansion coefficient and thus to extract reliable uncertainties even for the dose rate evaluated. The resulting function agrees well with new measurements made at fixed geographic positions and during long haul flights covering a wide range of latitudes.

Beta-Adrenergic Blockade Does not Prevent Polycythemia or Decrease in Plasma Volume in Men at 4300 m Altitude

NASA Technical Reports Server (NTRS)

Grover, R. F.; Selland, M. A.; McCullough, R. G.; Dahms, T. E.; Wolfel, E. E.; Butterfield, G. E.; Reeves, J. T.; Greenleaf, J. E.

1998-01-01

When humans ascend to high altitude (ALT) their plasma volume (PV) and total blood volume (BV) decrease during the first few days. With continued residence over several weeks, the hypoxia-induced stimulation of erythropoietin increases red cell production which tends to restore BV. Because hypoxia also activates the beta-adrenergic system, which stimulates red blood cell production, we investigated the effect of adrenergic beta-receptor inhibition with propranolol on fluid volumes and the polycythemic response in 11 healthy unacclimatized men (21-33 years old exposed to an ALT of 4300 m (barometric pressure 460 Torr) for 3 weeks on Pikes Peak, Colorado. PV was determined by the Evans blue dye method (PV(sub EB)), BV by the carbon monoxide method (BV(sub CO)), red cell volume (RCV)was calculated from hematocrit (Hct) and BV(sub CO), and serum erythropoietin concentration ([EPO]) and reticulocyte count, were also determined. All determinations were made at sea level and after 9-11 (ALT-10) and 9-20 (ALT-20) days at ALT. At sea level and ALT, six men received propranolol (pro, 240 mg/day), and five received a placebo (pla). Effective beta-blockade did not modify the mean (SE) maximal values of [EPO] [pla: 24.9 (3.5) vs pro: 24.5 (1.5) mU/ml] or reticulocyte count [pla: 2.7 (0.7) vs pro: 2.2 (0.5)%]; nor changes in PV(sub EB)[pla: -15.8 (3.8) vs pro: -19.9 (2.8)%], RCV(sub CO) [pla: +7.0 (6.7) vs pro: +10.1 (6.1)%], or BV(sub CO) [pla: -7.3 (2.3) vs pro: -7.1 (3.9)%]. In the absence of weight loss, a redistribution of body water with no net loss is implied. Hence, activation of the beta-adrenergic system did not appear to affect the hypovolemic or polycythemic responses that occurred during 3 weeks at 4300 m ALT in these subjects.

Trial Burn Plan for a Transportable Incineration System (TIS) at the Savanna Army Depot Activity (SADA) Washout Lagoon Area

DTIC Science & Technology

1991-11-27

the methylene chloride/methanol mix. All test train components will be composited and explosives will be analyzed and reported on a total test train...check ute volume metering system nicked. dented. or cored . they Shall be note the barometric preure. nd the ulibration values ax the field test site...antimony, arsenic, cadmium, lead, selenium, thallium hollow cathode lamps (HCLs) or electrodeless discharge lamps (EDLs). [Same as EPA SW-846 Methods 7041

Tropospheric delays from GNSS for application in coastal altimetry

NASA Astrophysics Data System (ADS)

Fernandes, M. Joana; Pires, Nelson; Lázaro, Clara; Nunes, Alexandra L.

2013-04-01

In the scope of the development of an improved methodology for the computation of the wet tropospheric correction for coastal altimetry, based on the use of tropospheric delays derived from GNSS (Global Navigation Satellite Systems), various studies have been conducted aiming to improve the estimation, at global scale, of GNSS-derived tropospheric delays.Amongst these studies, two are presented in this paper: (1) a global assessment of zenith total delays (ZTD) determined at international data centres such as EPN (EUREF Permanent Network) and IGS (International GNSS Service) by comparison with ZTD solutions computed at the University of Porto (U.Porto) using state-of-the-art methodologies and ZTD estimated from ERA Interim, the latest reanalysis dataset from ECMWF (European Centre for Medium-Range Weather Forecasts), (2) evaluation of the accuracy of the hydrostatic component of the tropospheric delay (zenith hydrostatic delay, ZHD) estimation from different sources of surface pressure.When compared with ERA Interim, both IGS and U.Porto ZTD are homogeneous with a mean standard deviation of the differences, for all analysed sites, of 12 mm. The U.Porto and IGS ZTD agree within 4 mm (1σ), while for EPN the same result is only valid for the period after November 2006. Before that date, the EPN solutions are slightly degraded and require an adequate correction.Aiming to evaluate the accuracy of ZHD determination from various sources of atmospheric pressure, a study is presented that compares ZHD values determined with in situ measurements of surface pressure at a global set of 63 coastal barometric sites (GNSS stations), the corresponding values obtained from ECMWF operational model, ERA Interim sea level pressure (SLP) and ZHD from the Vienna Mapping Functions 1 (VMF1).Results show that the global grids of sea level pressure provided by ECMWF operational model, either at 0.25° or 0.125° spacing, or the ERA Interim reanalysis product at 1.5°, allow the estimation of the hydrostatic component of the tropospheric delay with an accuracy of 1 to 3 mm at global scale, provided an adequate model for the height dependence of atmospheric pressure is adopted. In comparison, for VMF1 grids provided at 2.5° spacing, although the overall accuracy of ZHD estimation is 2-4 mm in most sites, in regions with high variability and strong seasonal signal in the surface pressure, VMF1 can reveal errors with a clear annual pattern and epochs for which the error exceeds the centimetre level. When used to estimate the wet component of the tropospheric delay (zenith wet delay, ZWD) for coastal altimetry, these errors can translate into errors of similar magnitude in sea level studies.

Hydrology of the unsaturated zone, Yucca Mountain, Nevada

USGS Publications Warehouse

Lecain, Gary D.; Stuckless, John S.

2012-01-01

The unsaturated zone at Yucca Mountain was investigated as a possible site for the nation's first high-level nuclear waste repository. Scientific investigations included infiltration studies, matrix properties testing, borehole testing and monitoring, underground excavation and testing, and the development of conceptual and numerical models of the hydrologic processes at Yucca Mountain. Infiltration estimates by empirical and geochemical methods range from 0.2 to 1.4 mm/yr and 0.2–6.0 mm/yr, respectively. Infiltration estimates from numerical models range from 4.5 mm/yr to 17.6 mm/yr. Rock matrix properties vary vertically and laterally as the result of depositional processes and subsequent postdepositional alteration. Laboratory tests indicate that the average matrix porosity and hydraulic conductivity values for the main level of the proposed repository (Topopah Spring Tuff middle nonlithophysal zone) are 0.08 and 4.7 × 10−12 m/s, respectively. In situ fracture hydraulic conductivity values are 3–6 orders of magnitude greater. The permeability of fault zones is approximately an order of magnitude greater than that of the surrounding rock unit. Water samples from the fault zones have tritium concentrations that indicate some component of postnuclear testing. Gas and water vapor movement through the unsaturated zone is driven by changes in barometric pressure, temperature-induced density differences, and wind effects. The subsurface pressure response to surface barometric changes is controlled by the distribution and interconnectedness of fractures, the presence of faults and their ability to conduct gas and vapor, and the moisture content and matrix permeability of the rock units. In situ water potential values are generally less than −0.2 MPa (−2 bar), and the water potential gradients in the Topopah Spring Tuff units are very small. Perched-water zones at Yucca Mountain are associated with the basal vitrophyre of the Topopah Spring Tuff or the Calico Hills bedded tuff. Thermal gradients in the unsaturated zone vary with location, and range from ~2.0 °C to 6.0 °C per 100 m; the variability appears to be associated with topography. Large-scale heater testing identified a heat-pipe signature at ~97 °C, and identified thermally induced and excavation-induced changes in the stress field. Elevated gas-phase CO2 concentrations and a decrease in the pH of water from the condensation zone also were identified. Conceptual and numerical flow and transport models of Yucca Mountain indicate that infiltration is highly variable, both spatially and temporally. Flow in the unsaturated zone is predominately through fractures in the welded units of the Tiva Canyon and Topopah Spring Tuffs and predominately through the matrix in the Paintbrush Tuff nonwelded units and Calico Hills Formation. Isolated, transient, fast-flow paths, such as faults, do exist but probably carry only a small portion of the total liquid-water flux at Yucca Mountain. The Paintbrush Tuff nonwelded units act as a storage buffer for transient infiltration pulses. Faults may act as flow boundaries and/or fast pathways. Below the proposed repository horizon, low-permeability lithostratigraphic units of the Topopah Spring Tuff and/or the Calico Hills Formation may divert flow laterally to faults that act as conduits to the water table. Advective transport pathways are consistent with flow pathways. Matrix diffusion is the major mechanism for mass transfer between fractures and the matrix and may contribute to retardation of radionuclide transport when fracture flow is dominant. Sorption may retard the movement of radionuclides in the unsaturated zone; however, sorption on mobile colloids may enhance radionuclide transport. Dispersion is not expected to be a major transport mechanism in the unsaturated zone at Yucca Mountain. Natural analogue studies support the concepts that percolating water may be diverted around underground openings and that the percentage of infiltration that becomes seepage decreases as infiltration decreases.

Influence of El Niño–Southern Oscillation (ENSO) events on the evolution of central California's shoreline

USGS Publications Warehouse

Storlazzi, Curt D.; Griggs, Gary B.

2000-01-01

Significant sea-cliff erosion and storm damage occurred along the central coast of California during the 1982–1983 and 1997–1998 El Niño winters. This generated interest among scientists and land-use planners in how historic El Niño–Southern Oscillation (ENSO) winters have affected the coastal climate of central California. A relative ENSO intensity index based on oceanographic and meteorologic data defines the timing and magnitude of ENSO events over the past century. The index suggests that five higher intensity (relative values 4–6) and 17 lower intensity (relative values 1–3) ENSO events took place between 1910 and 1995. The ENSO intensity index correlates with fluctuations in the time series of cyclone activity, precipitation, detrended sea level, wave height, sea-surface temperature, and sea-level barometric pressure. Wave height, sea level, and precipitation, which are the primary external forcing parameters in sea-cliff erosion, increase nonlinearly with increasing relative ENSO event intensity. The number of storms that caused coastal erosion or storm damage and the historic occurrence of large-scale sea-cliff erosion along the central coast also increase nonlinearly with increasing relative event intensity. These correlations and the frequency distribution of relative ENSO event intensities indicate that moderate- to high-intensity ENSO events cause the most sea-cliff erosion and shoreline recession over the course of a century.