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Safer Vehicles for People and the Planet
Motor vehicles contribute to climate change and petroleum dependence. Improving their fuel economy by making them lighter need not compromise safety. The cars and trucks plying America's roads and highways generate roughly 20 percent of the nation's total emissions of carbon dioxide, a pollutant that is, of course, of increasing concern because of its influence on climate. Motor vehicles also account for most of our country's dependence on imported petroleum, the price of which has recently skyrocketed to near-record levels. So policymakers would welcome the many benefits that would accrue from lessening the amount of fuel consumed in this way. Yet lawmakers have not significantly tightened new vehicle fuel-economy standards since they were first enacted three decades ago. Since then, manufacturers have, for the most part, used advances in automotive technology, ones that could have diminished fuel consumption, to boost performance and increase vehicle weight. In addition, the growth in popularity of pickups, sport utility vehicles (SUVs) and minivans--and the large amounts of gas they typically guzzle--has resulted in the average vehicle using the same amount of fuel per mile as it did 20 years ago. One of the historical impediments to imposing tougher fuel-economy standards has been the long-standing worry that reducing the mass of a car or truck to help meet these requirements would make it more dangerous to its occupants in a crash. People often justify this concern in terms of 'simple physics', noting, for example, that, all else being equal, in a head-on collision, the lighter vehicle is the more strongly decelerated, an argument that continues to sway regulators, legislators and many in the general public. We have spent the past several years examining the research underlying this position--and some recent work challenging it. We have also conducted our own analyses and come to the conclusion that the claim that lighter vehicles are inherently dangerous to those riding in them is flawed. For starters, all else is never equal; other aspects of vehicle design appear to control what really happens in a crash, as reflected in the safety record of different kinds of vehicles. What's more, the use of high-strength steel, light-weight metals such as aluminum and magnesium, and fiber-reinforced plastics now offers automotive engineers the means to fashion vehicles that are simultaneously safer and less massive than their predecessors, and such designs would, of course, enjoy the better fuel economy that shedding pounds brings
Jake Wells Enterprises and the Development of Urban Entertainments in the South, 1890-1925
This dissertation explores the development of commercial entertainments and film exhibition in the urban South around the turn of the last century through the growth and decline of Jake Wells Enterprises. A former professional baseball player, Wells invested in a wide variety of public amusements, with the core of his early business centered on establishing and organizing a string of vaudeville, popularly priced, and legitimate theaters throughout the largest cities in the region, a network he later transitioned to showing exclusively motion pictures. A thorough analysis of period newspapers, trade journals, and some business records covering Wellsâ career provides much-needed evidence for film and cultural historians wishing to understand the genesis and evolution of public amusements in the region, and its negotiation of traditional social and cultural institutions. In the 1890s, Wells played and managed several professional baseball teams in the South. The sport educated players and spectators alike to both the values and creed of New South progress, and to rising tensions confronting the intersection of modern and traditional forms of culture. Using his experiences and contacts gained in baseball, Wells helped foster a culture of entrepreneurship and innovation required for the progress of media industries in the region, establishing social networks of knowledge and improving distribution flows of entertainment. The dissertation explores how race and the genteel emerged as regional characteristics most influential to the success of this conversion in many urban areas. Protestants and evangelical culture served as the bulkhead supporting opposition to new amusements. Wellsâ expansion plans and violations of Sabbath day laws evoked a âspatialâ battle between commercialism and religion where political, social, and cultural power drawn from place and identity were challenged and reconfigured. Another chapter explores the exhibition and reception of early Civil War films in the region. Wells and other exhibitors were influential in their production and circulation nationwide, and positioned cinema as an alternative shrine to commemorate the Lost Cause in many communities. The last chapter shows how Wells failed to meet local demands and consumer desires in competition with the rise of national chain theaters and Hollywoodâs vertical integration
An Analysis of Functional Status in Multiple Sclerosis Patients after Progressive Non-Aerobic High-Intensity Maximal Effort Exercise (MEE)
Background: Multiple Sclerosis (MS) is a disease with a wide-ranging impact on functional status. MS patient function has been assessed using Multiple Sclerosis Functional Composite Score (MSFCS). The MSFCS includes the standardized scores (Z-score) of three functional tests: the Paced Auditory Serial Addition Test (PASAT-3â) for cognitive function, 9-Hole Peg Test (9-HPT) for upper extremity function, and timed 25-foot walk (25-TW) for lower extremity function. One of the most common symptoms experienced by MS patients is severe fatigue, often brought on suddenly by aerobic exercise. Non-aerobic maximal effort exercise (MEE) is thought to increase strength without increasing fatigue. The IsoPUMPÂź (Neuromuscular Engineering; Nashville, TN) is a stationary exercise device designed for patient use to safely perform MEE leg presses and whole body lunges using isometric and eccentric exercises. The progressive functional changes of the MS patients were tracked using the MSFCs at specific intervals during the study
The Effect of Progressive Non-Aerobic High-Intensity Maximal Effort Exercise (MEE) on the Health-Related Quality of Life in Patients with Multiple Sclerosis
Background: Studies indicate that Multiple Sclerosis (MS) patients are less satisfied with the quality of their lives than healthy individuals in similar circumstances. Common symptoms experienced include fatigue, cognitive dysfunction, pain, spasticity, depression, bladder/bowel dysfunction and sexual dysfunction. Several pharmacological and non-pharmacological methods have been employed for such symptoms to try to increase quality of life and reduce the mortality rate. Non-pharmacological methods recommended for MS patients include lifestyle modifications, exercise programs and physical therapy. MS patients easily fatigue during aerobic exercise but a non-aerobic progressive maximal effort exercise (MEE) protocol consisting of a few short, duration isometric and eccentric leg press and whole body lunges was previously seen to increase strength without increasing fatigue. The IsoPUMPÂź (Neuromuscular Engineering, Nashville TN) exercise system permitted safe conduct and measurement of muscle strength and duration during each exercise repetition
Effects of Non-Aerobic Maximal Effort Exercise on Fatigue in Deconditioned Men and Women with Multiple Sclerosis
Multiple Sclerosis (MS) is a neurodegenerative disease of unknown etiology affecting women more frequently than men. Mental and physical fatigue complaints are often the most disabling symptoms for an MS patient. Both are multifactorial, potentially exacerbated by aerobic exercise, may prevent sustained physical functioning, and significantly interfere with activities of daily living1. A multi-center study was designed to investigate the effects of non-aerobic maximal effort exercise (MEE) for deconditioned persons with MS, with the expectation of minimizing fatigue. The IsoPUMP (Neuromuscular Engineering; Nashville, TN), is a specialized exercise and strength-sensing machine, designed to allow individuals to safely perform and record their non-aerobic MEE sessions. The Modified Fatigue Impact Scale (MFIS) and Multiple Sclerosis Functional Composite (MSFC) are common, accepted methods used to measure fatigue and function. The MFIS is a 21-item questionnaire which assesses the subjectsâ perception of physical, cognitive, and psychosocial aspects of fatigue over a four-week period2. Each of the 21 items are scored on a scale from 0 (never) to 4 (almost always), and the total MFIS score is calculated by summing the circled number for each item. Total scores can range from 0 to 84; higher scores indicating a greater impact of fatigue on the person. The MFIS has three distinct subscales: (1) physical, (2) cognitive, and (3) psychosocial. These subscales can be scored independently by summing the questions that pertain to each subscale2. The MFIS physical subscale score can range from 0 â 36 and the MFIS cognitive subscale score can range from 0 â 40. The MSFC combines clinical measures used to assess lower limb function (Timed 25-Foot Walk [25-FW]), upper limb function (9-Hole Peg Test [9-HPT]), and cognition (Paced Auditory Serial Addition Test [PASAT-3â])3. The 25-FW is a quantitative measure of lower extremity function. The 9-HPT is a quantitative measure of arm and hand function where a subject inserts and then removes 9 pegs from a board, using one hand at a time. The time is recorded for each hand with the dominant hand trial first and the non-dominant hand trial second. The final score is recorded as the mean time for both hands. The PASAT-3â is a measure of cognitive function, specifically assessing auditory information processing speed, short-term memory, flexibility, and calculation ability. Cognitive dysfunction affects half of all MS patients; slowing ability to reason, concentrate, and recall5. In this test subjects listen to a series of 61 spoken numbers separated by 3 seconds and must add each number to the prior number. Their final PASAT-3â score is the number of correct additions in the series, with 60 reflecting a perfect score. The MSFC is then evaluated by creating Z-scores for each component, which compare each outcome with the average outcome of the study population. The three Z-scores are then averaged to create an overall composite score (the MSFC score) which represents change over time for that population of MS subjects3
Shape modeling technique KOALA validated by ESA Rosetta at (21) Lutetia
We present a comparison of our results from ground-based observations of
asteroid (21) Lutetia with imaging data acquired during the flyby of the
asteroid by the ESA Rosetta mission. This flyby provided a unique opportunity
to evaluate and calibrate our method of determination of size, 3-D shape, and
spin of an asteroid from ground-based observations. We present our 3-D
shape-modeling technique KOALA which is based on multi-dataset inversion. We
compare the results we obtained with KOALA, prior to the flyby, on asteroid
(21) Lutetia with the high-spatial resolution images of the asteroid taken with
the OSIRIS camera on-board the ESA Rosetta spacecraft, during its encounter
with Lutetia. The spin axis determined with KOALA was found to be accurate to
within two degrees, while the KOALA diameter determinations were within 2% of
the Rosetta-derived values. The 3-D shape of the KOALA model is also confirmed
by the spectacular visual agreement between both 3-D shape models (KOALA pre-
and OSIRIS post-flyby). We found a typical deviation of only 2 km at local
scales between the profiles from KOALA predictions and OSIRIS images, resulting
in a volume uncertainty provided by KOALA better than 10%. Radiometric
techniques for the interpretation of thermal infrared data also benefit greatly
from the KOALA shape model: the absolute size and geometric albedo can be
derived with high accuracy, and thermal properties, for example the thermal
inertia, can be determined unambiguously. We consider this to be a validation
of the KOALA method. Because space exploration will remain limited to only a
few objects, KOALA stands as a powerful technique to study a much larger set of
small bodies using Earth-based observations.Comment: 15 pages, 8 figures, 2 tables, accepted for publication in P&S
Kinetics of maternal immunity against rabies in fox cubs (Vulpes vulpes)
BACKGROUND: In previous experiments, it was demonstrated that maternal antibodies (maAb) against rabies in foxes (Vulpes vulpes) were transferred from the vixen to her offspring. However, data was lacking from cubs during the first three weeks post partum. Therefore, this complementary study was initiated. METHODS: Blood samples (n = 281) were collected from 64 cubs (3 to 43 days old) whelped by 19 rabies-immune captive-bred vixens. Sera was collected up to six times from each cub. The samples were analysed by a fluorescence focus inhibition technique (RFFIT), and antibody titres (nAb) were expressed in IU/ml. The obtained data was pooled with previous data sets. Subsequently, a total of 499 serum samples from 249 cubs whelped by 54 rabies-immune vixens were fitted to a non-linear regression model. RESULTS: The disappearance rate of maAb was independent of the vixens' nAb-titre. The maAb-titre of the cubs decreased exponentially with age and the half-life of the maAb was estimated to be 9.34 days. However, maAb of offspring whelped by vixens with high nAb-titres can be detected for longer by RFFIT than that of offspring whelped by vixens with relatively low nAb-titres. At a mean critical age of about 23 days post partum, maAb could no longer be distinguished from unspecific reactions in RFFIT depending on the amount of maAb transferred by the mother. CONCLUSIONS: The amount of maAb cubs receive is directly proportional to the titre of the vixen and decreases exponentially with age below detectable levels in seroneutralisation tests at a relatively early age
Automated Detection of Infectious Disease Outbreaks in Hospitals: A Retrospective Cohort Study
Susan Huang and colleagues describe an automated statistical software, WHONET-SaTScan, its application in a hospital, and the potential it has to identify hospital infection clusters that had escaped routine detection
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