1,040 research outputs found

    First-Year Effects of the Energy Crisis on Traffic in Kentucky (Rural Highways)

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    The Arab oil embargo in mid-October 1973 curtailed availability of gasoline. Fuel conservation measures resulted in reduced travel and decreased traffic speeds. On March 1, 1974, posted speed was set at 55 mph (88 km/h) on rural highways in Kentucky. Traffic volumes, speeds, and accidents for the rural highway during the period known as the energy crisis and its after effects were compared to the corresponding period a year earlier. Traffic volumes began to decline in December 1973 and continued through September 1974. Total travel in the 12 months through November 1974 decreased by 2.3 percent; traffic increased by five percent in 1973. Accident rates during this period decreased by 13.5 percent; and the largest decreases were associated with the highways experiencing the greatest reductions in travel speed. The relationship between traffic speed and accident rate showed a great decrease in accident rate as traffic speeds decreased. Differences between wet-surface and dry-surface accident rates were especially significant and were more so for interstate than for two-lane highways. Improved wet-pavement skid resistance at the lower speeds obviously contributed to a reduction in accident rates. Continuation of the 55-mph (88 km/h) speed limit on all rural highways would seem advisable

    Traffic Accidents: Day Versus Night

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    A comparison of accidents during daylight and darkness was made for both rural and urban roads. Accident rates on all types of rural roads were higher during darkness than during daylight. Critical accident rates during darkness for various types of roads were calculated. In urban areas, a larger percentage of accidents occurred on wet pavements during darkness than during daylight, but there were no significant differences for rural roads. No significant difference was found between average speeds during conditions of daylight and darkness. On rural roads, imposition of the 24.6-m/s (55-mph) speed limit resulted in a reduction in accident rates for both daylight and darkness. However, there were changes in the percentages of wet-pavement accidents on rural roads. For the entire rural system, there was a decrease in the percentages of wet-pavement accidents during daylight and an increase during darkness

    Traffic Accidents: Day vs. Night

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    A comparison of accidents during daylight and darkness was made for both rural and urban roads. Accident rates on all types of rural roads were higher during darkness than during daylight. Critical accident rates during darkness for various types of roads were calculated. In urban areas, a larger percentage of accidents occurred on wet pavements during darkness than during daylight, but there were no significant differences for rural roads. No significant difference was found between average speeds during conditions of daylight and darkness. On rural roads, imposition of the 55-mph (24.6-m/s) speed limit resulted in a reduction in accident rates for both daylight and darkness. However, there were changes in the percentages of wet-pavement accidents on rural roads. For the entire rural system, there was a decrease in the percentages of wet-pavement accidents during daylight and an increase during darkness

    First-Year Effects of the Energy Crisis on Traffic in Kentucky (Rural Highways) [May 1975]

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    The Arab oil embargo in mid-October 1973 curtailed availability of gasoline. Fuel conservation measures resulted in reduced travel and decreased traffic speeds. On March 1, 1974, posted speed was set at 55 mph (24.6 m/s) on rural highways in Kentucky. Traffic volumes, speeds, and accidents for the rural highway during the period known as the energy crisis and its after effects were compared to the corresponding period a year earlier. Traffic volumes began to decline in December 1973 and continued through September 1974. Total travel in the 12 months through November 1974 decreased by 2.3 percent; traffic increased by five percent in 1973. Accident rates during this period decreased by 13.5 percent; and the largest decreases were associated with the highways experiencing the greatest reductions in travel speed. The relationship between traffic speed and accident rate showed a great decrease in accident rate as traffic speeds decreased. Differences between wet-surface and dry-surface accident rates were especially significant and were more so for interstate than for two-lane highways. Improved wet-pavement skid resistance at the lower speeds obviously contributed to a reduction in accident rates. Continuation of the 55-mph (24.6 m/s) speed limit on all rural highways would seem advisable

    Effects of the Energy Crisis on Traffic in Kentucky

    Get PDF
    The Arab oil embargo in mid-October 1973 curtailed availability of gasoline. Fuel conservation measures resulted in reduced travel and decreased traffic speeds. On March 1, 1974, posted speed was set at 55 mph on rural highways in Kentucky. Traffic volumes, speeds, and accidents for the rural highway during the period known as the energy crisis and its after effects were compared to the corresponding period a year earlier. Traffic volumes began to decline in December 1973 but began to rise again in March 1974. Total travel in the seven months through June 1974 decreased by 3.5 percent; traffic increased by 5 percent in 1973. Accident rates during this period decreased by 13.6 percent; and the largest decreases were associated with the highways experiencing the greatest reductions in travel speed. The relationship between traffic speed and accident rate showed a great decrease in accident rate as traffic speeds decreased. Differences between wet-surface and dry-surface accident rates were especially significant and were more so for interstate than for two-lane highways. Improved wet-pavement skid resistance at the lower speeds obviously contributed to a reduction in accident rates. Continuation of the 55-mph speed limit on all rural highways would seem advisable

    Analysis of Weekday, Weekend, and Holiday Accident Frequencies

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    Trends in recent years have indicated that a significant percentage of weekend traffic is recreational and that the proportion of weekend trips is increasing. The energy crisis in late 1973, and the associated reduction in speed limit on March 1, 1974, affected weekend travel. A previous study by the Division of Research revealed that significant reductions in the number and rates of highway accidents, fatalities, and injuries coincided with the period of time generally referred to as the energy crisis . Lower speeds were considered to be a primary factor in the reduction of accidents. An alteration in weekend and holiday trips was suspected of contributing to the reduction of accident rates; however, information was lacking from which to make this determination. A comparison of accidents during weekday, weekend, and holiday periods was made; most of the data were for rural sections of two-lane roads, four-lane roads, interstate routes, and toll roads. On rural roads, the largest number of accidents have occurred on Saturdays, Fridays, and Sundays. Tuesdays generally had the lowest number of accidents. Fatal accidents on two-lane roads occurred in similar random patterns of distribution during the week. The highest rates for two-lane roads were on Sundays and Saturdays, and the rates for expressways (interstates and toll roads) were the highest on Sundays. Fatality rates were distributed similarly to the rates of all accidents. The percentage of accidents on weekends decreased steadily from 35 in 1973 to 32 in 1976. likewise, the percentage of fatalities on weekends showed gradual decreases. Accident rates on weekends were substantially higher than on weekdays. Rates of fatal and an accidents were lower during holiday periods than during weekends not involving holidays. Holiday periods had fewer accidents per day than weekends but had more accidents per day than weekdays. Traffic volumes, however, were significantly greater during holidays than on either weekends or weekdays

    Analysis of Weekday, Weekend, and Holiday Accident Frequencies

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    On rural roads, the largest number of accidents have occurred on Saturdays, Fridays, and Sundays, respectively. Tuesdays generally had the lowest number of accidents. The highest accident rates for two-lane roads were on Sundays and Saturdays, and the rates for expressways (interstates and toll roads) were the highest on Sundays. Accident rates on weekends were substantially higher than on weekdays. Rates of fatal and all accidents were lower during holiday periods than during weekends not involving holidays. Holiday periods had fewer accidents per day than weekends but had more accidents per day than weekdays. Traffic during holidays, however, was significantly greater than on either weekends or weekdays

    Body Condition, Nutrition and Reproduction of Beef Cows

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    12 pp., 7 tables, 2 charts, 9 photosProducers must be able to evaluate beef cows' body reserves and to relate the evaluation to reproductive and nutritional management. Topics discussed include the practical importance of body condition scoring and various BCS suggestions

    Martian low-temperature alteration materials in shock-melt pockets in Tissint: Constraints on their preservation in shergottite meteorites

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    We apply an array of in situ analytical techniques, including electron and Raman microscopy, electron and ion probe microanalysis, and laser ablation mass spectrometry to the Tissint martian meteorite in order to find and elucidate a geochemical signature characteristic of low-temperature alteration at or near the martian surface. Tissint contains abundant shock-produced quench-crystallized melt pockets containing water in concentrations ranging from 73 to 1730 ppm; water content is positively correlated with Cl content. The isotopic composition of hydrogen in the shock-produced glass ranges from δD = 2559 to 4422 ‰. Water is derived from two distinct hydrogen reservoirs: the martian near-surface (>500 ‰) and the martian mantle (-100 ‰). In one shock melt pocket comprising texturally homogeneous vesiculated glass, the concentration of H in the shock melt decreases while simultaneously becoming enriched in D, attributable to the preferential loss of H over D to the vesicle while the pocket was still molten. While igneous sulfides are pyrrhotite in composition (Fe_(0.88-0.90)S), the iron to sulfur ratios of spherules in shock melt pockets are elevated, up to Fe_(1.70)S, which we attribute to shock-oxidation of igneous pyrrhotite and the formation of hematite at high temperature. The D- and Cl-enrichment, and higher oxidation of the pockets (as indicated by hematite) support a scenario in which alteration products formed within fractures or void spaces within the rock; the signature of these alteration products is preserved within shock melt (now glass) which formed upon collapse of these fractures and voids during impact shock. Thermal modeling of Tissint shock melt pockets using the HEAT program demonstrates that the shock melt pockets with the greatest potential to preserve a signature of aqueous alteration are small, isolated from other regions of shock melt, vesicle-free, and glassy

    Human longevity: 25 genetic loci associated in 389,166 UK biobank participants

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    This is the final version. Freely available on open access from Impact Journals via the DOI in this recordA public use file of data from the WLS is available from the Wisconsin Longitudinal Study, University of Wisconsin-Madison, 1180 Observatory Drive, Madison, Wisconsin 53706 and at (http://www.ssc.wisc.edu/wlsresearch/data).We undertook a genome-wide association study (GWAS) of parental longevity in European descent UK Biobank participants. For combined mothers' and fathers' attained age, 10 loci were associated (p<5*10-8), including 8 previously identified for traits including survival, Alzheimer's and cardiovascular disease. Of these, 4 were also associated with longest 10% survival (mothers age ≥90 years, fathers ≥87 years), with 2 additional associations including MC2R intronic variants (coding for the adrenocorticotropic hormone receptor). Mother's age at death was associated with 3 additional loci (2 linked to autoimmune conditions), and 8 for fathers only. An attained age genetic risk score associated with parental survival in the US Health and Retirement Study and the Wisconsin Longitudinal Study and with having a centenarian parent (n=1,181) in UK Biobank. The results suggest that human longevity is highly polygenic with prominent roles for loci likely involved in cellular senescence and inflammation, plus lipid metabolism and cardiovascular conditions. There may also be gender specific routes to longevity.This work was generously funded by an award to DM and LH by the Medical Research Council MR/M023095/1. LF is supported by the Intramural Research Program of the National Institute on Aging, U.S. National Institutes of Health. Input from CK and GK was supported by the University of Connecticut Health Center. The Health and Retirement Study (HRS) is a longitudinal project sponsored by the National Institute on Aging (NIA U01AG009740) and the Social Security Administration. This research uses data from the Wisconsin Longitudinal Study (WLS) of the University of Wisconsin-Madison. Since 1991, the WLS has been supported principally by the National Institute on Aging (AG09775, AG21079 and AG33285), with additional support from the Vilas Estate Trust, the National Science Foundation, the Spencer Foundation and the Graduate School of the University of Wisconsin-Madison
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