790 research outputs found
Influencing the decline of lung function in COPD: use of pharmacotherapy
Chronic obstructive pulmonary disease (COPD) is a common and deadly disease. One of the hallmarks of COPD is an accelerated decline in lung function, as measured by spirometry. Inflammation, oxidative stress and other pathways are hypothesized to be important in this deterioration. Because progressive airflow obstruction is associated with considerable morbidity and mortality, a major goal of COPD treatment has been to slow or prevent the accelerated decline in lung function. Until recently, the only known effective intervention was smoking cessation. However, newly reported large clinical trials have shown that commonly used medications may help slow the rate of lung function decline. The effect of these medications is modest (and thus required such large, expensive trials) and to be of clinical benefit, therapy would likely need to start early in the course of disease and be prolonged. Such a treatment strategy aimed at preservation of lung function would need to be balanced against the side effects and costs of prolonged therapy. A variety of newer classes of medications may help target other pathophysiologically important pathways, and could be used in the future to prevent lung function decline in COPD
Is the way to man's heart (and lung) through the abdomen?
Intra-abdominal hypertension is increasingly recognized to be both prevalent and clinically important in medical and surgical intensive care units. Intra-abdominal pressure (IAP) can impact organ function throughout the body, and it can also complicate standard measurements used in intensive care units. The article by Krebs and colleagues reports the effect of IAP on respiratory function, gas exchange and hemodynamic function. Their results show a relatively small effect of modestly elevated IAP on these variables in their patient population. However, their work raises several questions for clinicians and researchers regarding the pathophysiology and management of IAP
Potential vorticity structure in the North Atlantic western boundary current from underwater glider observations
Author Posting. © American Meteorological Society, 2016. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 46 (2016): 327–348, doi:10.1175/JPO-D-15-0112.1.Potential vorticity structure in two segments of the North Atlantic’s western boundary current is examined using concurrent, high-resolution measurements of hydrography and velocity from gliders. Spray gliders occupied 40 transects across the Loop Current in the Gulf of Mexico and 11 transects across the Gulf Stream downstream of Cape Hatteras. Cross-stream distributions of the Ertel potential vorticity and its components are calculated for each transect under the assumptions that all flow is in the direction of measured vertically averaged currents and that the flow is geostrophic. Mean cross-stream distributions of hydrographic properties, potential vorticity, and alongstream velocity are calculated for both the Loop Current and the detached Gulf Stream in both depth and density coordinates. Differences between these mean transects highlight the downstream changes in western boundary current structure. As the current increases its transport downstream, upper-layer potential vorticity is generally reduced because of the combined effects of increased anticyclonic relative vorticity, reduced stratification, and increased cross-stream density gradients. The only exception is within the 20-km-wide cyclonic flank of the Gulf Stream, where intense cyclonic relative vorticity results in more positive potential vorticity than in the Loop Current. Cross-stream gradients of mean potential vorticity satisfy necessary conditions for both barotropic and baroclinic instability within the western boundary current. Instances of very low or negative potential vorticity, which predispose the flow to various overturning instabilities, are observed in individual transects across both the Loop Current and the Gulf Stream.Glider operations in the Gulf Stream were supported by the National Science Foundation under Grant OCE-0220769. Glider operations in the Gulf of Mexico were supported by BP. R.E.T. was supported by the Penzance Endowed Fund in Support of Assistant Scientists and the Independent Research and Development Program at WHOI.2016-07-0
A Half Century of Crop Rotation
Fifty-three years of crop rotation studies, started in 1894, were concluded in the fall of 1946. These experiments were on Bridgehampton very fine sandy loam soil that was originally acid and produced meager crops. Within a very few years it became evident that the yields of crops could be materially increased by the use of agricultural lime and chemical fertilizers. The records of the last 17 years of the experiments are reported in this bulletin and comparisons are made with results from former years. The 3 rotations described in this bulletin are known as rotations B, E, and F. B was a 6-year sequence: 1 year of potatoes followed by a year of ensilage corn and 4 years of alfalfa-timothy hay. Rotations E and F were 5-year sequences in which potatoes were followed by Rhode Island White Flint corn and 3 years of hay. Rotation E contained alfalfa, red clover and alsike clover as well as timothy and redtop in the grass seed mixture. The meadow seeding for rotation F consisted of timothy and redtop grasses. The average yields of Irish Cobbler potatoes were: 222 bushels per acre on the clover rotation, 246 bushels per acre on the alfalfa rotation and 294 bushels per acre on the timothy-redtop rotation. The superior yields of potatoes after the non-legume hay is thought to result, in part, from a more favorable supply and balance of potassium, calcium and magnesium left by the grass crop. Rhode Island White Flint corn yielded slightly more grain when grown after the legume-grass hay rather than grass hay alone. The supply of available nitrogen seemed to be a controlling factor influencing the yield of corn. The alfalfa-timothy seeding outyielded the general legume hay mixture during the second and third years. The non-legume seeding produced the smallest amount of hay with the least feed value. The general legume mixture usually produced more hay the first year because the biennial clovers that it contained appeared to mature more quickly than the alfalfa. The average net returns per acre were figured for 2 periods of 5 years, 1935-1939 and 1942-1946. During the first period these net returns per acre were 24.46 and 61.44, 39.85 respectively for these rotations
Innovative Financing for Global Education
Innovative financing is a growing prospect and priority in the education sector, where over 57 million children and youth do not have access to schools, and the funding gap for achieving basic education for all is estimated at 7 billion in additional financial resources through a range of new institutions and partnerships.This paper presents a comprehensive and practical analysis of the current state of innovative financing in global education. The report argues that education is a complex sector characterized by significant barriers to investment. But it also suggests how to break through these barriers using innovative financing such as solidarity levies and private sector investments through a global education investment bank.This research, carried out by the Innovative Finance Foundation, is part of the Open Society Education Support Program's efforts to identify innovative financing mechanisms and approaches that can increase the availability and allocation of resources for education systems
Absolute velocity estimates from autonomous underwater gliders equipped with Doppler current profilers
Author Posting. © American Meteorological Society, 2017. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Atmospheric and Oceanic Technology 34 (2017): 309-333, doi:10.1175/JTECH-D-16-0156.1.Doppler current profilers on autonomous underwater gliders measure water velocity relative to the moving glider over vertical ranges of O(10) m. Measurements obtained with 1-MHz Nortek acoustic Doppler dual current profilers (AD2CPs) on Spray gliders deployed off Southern California, west of the Galápagos Archipelago, and in the Gulf Stream are used to demonstrate methods of estimating absolute horizontal velocities in the upper 1000 m of the ocean. Relative velocity measurements nearest to a glider are used to infer dive-dependent flight parameters, which are then used to correct estimates of absolute vertically averaged currents to account for the accumulation of biofouling during months-long glider missions. The inverse method for combining Doppler profiler measurements of relative velocity with absolute references to estimate profiles of absolute horizontal velocity is reviewed and expanded to include additional constraints on the velocity solutions. Errors arising from both instrumental bias and decreased abundance of acoustic scatterers at depth are considered. Though demonstrated with measurements from a particular combination of platform and instrument, these techniques should be applicable to other combinations of gliders and Doppler current profilers.Spray glider missions
were supported by the National Science Foundation
(OCE-1232971, OCE-1233282), the National Oceanic
and Atmospheric Administration (NA10OAR4320156,
NA15OAR4320071), Eastman Chemical Company, the
Oceans and Climate Change Institute at WHOI, and the
W. Van Alan Clark Jr. Chair for Excellence in Oceanography
at WHOI. RET acknowledges additional
support for analysis and publication from the National
Science Foundation (OCE-1633911).2017-07-3
Incidence of physician-diagnosed osteoarthritis among active duty United States military service members
The article of record as published may be found at http://dx.DOI.org/10.1002/art.30498To examine the incidence of osteoarthritis
and the influence of demographic and occupational
factors associated with this condition among
active duty US service members between 1999 and 2008
Bifurcation and upwelling of the equatorial undercurrent west of the Galapagos Archipelago
Author Posting. © American Meteorological Society, 2020. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 50(4), (2020): 887-905, doi:10.1175/JPO-D-19-0110.1.The Equatorial Undercurrent (EUC) encounters the Galápagos Archipelago on the equator as it flows eastward across the Pacific. The impact of the Galápagos Archipelago on the EUC in the eastern equatorial Pacific remains largely unknown. In this study, the path of the EUC as it reaches the Galápagos Archipelago is measured directly using high-resolution observations obtained by autonomous underwater gliders. Gliders were deployed along three lines that define a closed region with the Galápagos Archipelago as the eastern boundary and 93°W from 2°S to 2°N as the western boundary. Twelve transects were simultaneously occupied along the three lines during 52 days in April–May 2016. Analysis of individual glider transects and average sections along each line show that the EUC splits around the Galápagos Archipelago. Velocity normal to the transects is used to estimate net horizontal volume transport into the volume. Downward integration of the net horizontal transport profile provides an estimate of the time- and areal-averaged vertical velocity profile over the 52-day time period. Local maxima in vertical velocity occur at depths of 25 and 280 m with magnitudes of (1.7 ± 0.6) × 10−5 m s−1 and (8.0 ± 1.6) × 10−5 m s−1, respectively. Volume transport as a function of salinity indicates that water crossing 93°W south (north) of 0.4°S tends to flow around the south (north) side of the Galápagos Archipelago. Comparisons are made between previous observational and modeling studies with differences attributed to effects of the strong 2015/16 El Niño event, the annual cycle of local winds, and varying longitudes between studies of the equatorial Pacific.This work was supported by National Science Foundation (Grants OCE-1232971 and OCE-1233282) and the NASA Earth and Space Science Fellowship Program (Grant 80NSSC17K0443)
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Sitting and Supine Esophageal Pressures in Overweight and Obese Subjects Authors
Esophageal pressure can be used to approximate pleural pressure and might be clinically useful, particularly in the obese e.g to guide mechanical ventilator settings in critical illness. However, mediastinal artifact (the difference between true pleural pressure and esophageal pressure) may limit acceptance of the measurement, and reproducibility of esophageal pressure measurements remains unknown. Therefore, we aimed to assess the effect of body posture on esophageal pressure in a cohort of obese but healthy subjects, some of whom had multiple measurements, to address the clinical robustness of esophageal manometry. Twenty-five overweight and obese subjects (BMI>25kg/m2) and 11 control lean subjects (BMI<25kg/m2) underwent esophageal manometry with pressures measured seated and supine. Twenty overweight and obese subjects had measurements repeated after ~1-2 weeks. Anthropometric data and sitting and supine spirometry were recorded. The average end-expiratory esophageal pressures sitting and supine were greater in the overweight and obese group than the lean group (sitting −0.1±2.1 vs. −3.3±1.2cmH2O, supine 9.3±3.3 vs. 6.9±2.8cmH2O, respectively). The mean differences between repeated measurements were small (−0.3 ± 1.7cmH2O sitting and −0.1 ± 1.5cmH2O supine). Esophageal pressures correlated with a number of anthropometric and spirometric variables. In conclusion, esophageal pressures are slightly greater in overweight and obese subjects than lean subjects; but changes with position are similar in both groups. These data indicate that mediastinal weight and postural effects on esophageal pressure are within a clinically acceptable range, and suggest that esophageal manometry can be used to inform clinical decision making across wide range of body types
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