Walking for Transportation: What do U.S. Adults Think is a Reasonable Distance and Time?
Watson, Kathleen B; Carlson, Susan A; Humbert-Rico, Tiffany; Carroll, Dianna D.; Fulton, Janet E
2015-01-01
Background Less than one-third of U.S. adults walk for transportation. Public health strategies to increase transportation walking would benefit from knowing what adults think is a reasonable distance to walk. Our purpose was to determine (1) what adults think is a reasonable distance and amount of time to walk and (2) whether there were differences in minutes spent transportation walking by what adults think is reasonable. Methods Analyses used a cross-sectional nationwide adult sample (n=3,653) participating in the 2010 Summer ConsumerStyles mail survey. Results Most adults (>90%) think transportation walking is reasonable. However, less than half (43%) think walking a mile or more or for 20 minutes or more is reasonable. What adults think is reasonable is similar across most demographic subgroups, except for older adults (≥ 65 years) who think shorter distances and times are reasonable. Trend analysis that adjust for demographic characteristics indicates adults who think longer distances and times are reasonable walk more. Conclusions Walking for short distances is acceptable to most U.S. adults. Public health programs designed to encourage longer distance trips may wish to improve supports for transportation walking to make walking longer distances seem easier and more acceptable to most U.S. adults. PMID:25158016
Walking for Transportation: What do U.S. Adults Think is a Reasonable Distance and Time?
Watson, Kathleen B; Carlson, Susan A; Humbert-Rico, Tiffany; Carroll, Dianna D; Fulton, Janet E
2015-06-16
Less than one-third of U.S. adults walk for transportation. Public health strategies to increase transportation walking would benefit from knowing what adults think is a reasonable distance to walk. Our purpose was to determine 1) what adults think is a reasonable distance and amount of time to walk and 2) whether there were differences in minutes spent transportation walking by what adults think is reasonable. Analyses used a cross-sectional nationwide adult sample (n = 3653) participating in the 2010 Summer ConsumerStyles mail survey. Most adults (> 90%) think transportation walking is reasonable. However, less than half (43%) think walking a mile or more or for 20 minutes or more is reasonable. What adults think is reasonable is similar across most demographic subgroups, except for older adults (≥ 65 years) who think shorter distances and times are reasonable. Trend analysis that adjust for demographic characteristics indicates adults who think longer distances and times are reasonable walk more. Walking for short distances is acceptable to most U.S. adults. Public health programs designed to encourage longer distance trips may wish to improve supports for transportation walking to make walking longer distances seem easier and more acceptable to most U.S. adults.
A Process-Based Transport-Distance Model of Aeolian Transport
NASA Astrophysics Data System (ADS)
Naylor, A. K.; Okin, G.; Wainwright, J.; Parsons, A. J.
2017-12-01
We present a new approach to modeling aeolian transport based on transport distance. Particle fluxes are based on statistical probabilities of particle detachment and distributions of transport lengths, which are functions of particle size classes. A computational saltation model is used to simulate transport distances over a variety of sizes. These are fit to an exponential distribution, which has the advantages of computational economy, concordance with current field measurements, and a meaningful relationship to theoretical assumptions about mean and median particle transport distance. This novel approach includes particle-particle interactions, which are important for sustaining aeolian transport and dust emission. Results from this model are compared with results from both bulk- and particle-sized-specific transport equations as well as empirical wind tunnel studies. The transport-distance approach has been successfully used for hydraulic processes, and extending this methodology from hydraulic to aeolian transport opens up the possibility of modeling joint transport by wind and water using consistent physics. Particularly in nutrient-limited environments, modeling the joint action of aeolian and hydraulic transport is essential for understanding the spatial distribution of biomass across landscapes and how it responds to climatic variability and change.
Economic comparisons of haul road construction versus forwarding versus longer skid distances
Michael D. Erickson; Curt C. Hassler; Chris B. LeDoux
1992-01-01
There currently exists no set of basic guidelines for Appalachian loggers to use in the decision making process for selecting the best way to harvest a tract of timber. Specifically, guidelines are needed for deciding between the alternatives of constructing truck haul roads to access an area or other alternatives such as skidding or forwarding timber longer distances...
Effects of travel distance and season of the year on transport-related mortality in cattle.
Simova, Veronika; Voslarova, Eva; Vecerek, Vladimir; Passantino, Annamaria; Bedanova, Iveta
2017-03-01
The number of animals that die during transport to a slaughterhouse or shortly after being delivered to a slaughterhouse may serve as an indicator of animal welfare during transport. The aim of this study was to determine the mortality rate in cattle resulting from transport to slaughter in the Czech Republic in the period from 2009 to 2014, and to investigate the effect of travel distance and season of the year. Transport-related mortality rates were recorded for all categories of cattle for the following travel distances: up to 50 km, 51-100 km, 101-200 km and over 200 km. Higher mortality rates occurred with shorter travel distances (<50 km and 51-100 km) when compared to longer travel distances (101-200 km and > 200 km), with a significant difference (P < 0.01) between short and long travel distances being found in feeders and dairy cows. Also, the season of the year had a significant impact on the mortality rate among transported cattle. The highest mortality rate in all categories was observed in spring months. The lowest mortality rate was found in autumn months for fat cattle and dairy cows and in winter months for feeders and calves. © 2016 Japanese Society of Animal Science.
Tejero, Pilar; Insa, Beatriz; Roca, Javier
2018-08-01
Would an increase in the default interletter spacing improve the legibility of words in traffic signs? Previous evidence on traffic sign design and recent studies on the cognitive processes involved in visual word recognition have provided conflicting results. The present work examined whether an increase in the default interletter spacing would improve the search of a word in direction traffic signs. To achieve this objective, twenty-two drivers participated in a driving simulation experiment. They followed a highway route and indicated whether a target place name was present among a set of distractors shown on direction traffic signs along the route. We compared the default interletter spacing of the Spanish "CC Rige" font (which is based on the internationally-used Transport font) and a 2.5-times expanded interletter spacing. The results revealed that the drivers were able to give a correct response at a distance to the traffic sign that was on average longer in the expanded than in the default spacing condition. This advantage in the legibility distance was observed in the absence of significant differences in reading accuracy, gaze behavior, or driving performance measures. Therefore, the evidence provided supports that drivers can benefit from a slight increase in interletter spacing relative to the standard spacing. Some of the design factors influencing this effect are discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.
[Intensive care within the context of military long-distance transport].
Hossfeld, B; Rohowsky, B; Rödig, E; Lampl, L
2004-05-01
Due to the changed task spectrum of the German Federal Armed Forces with participation in international deployments for UN and NATO the concept of Aeromedical Evacuation (MedEvac) gained a new quality for the Air Force as well as for the Medical Corps. The transport of mostly severely injured or critically ill patients requires both, medical equipment which has to be permanently adapted to the national standard, and qualified intensive-care-personnel. At present, the aircrafts used for such deployments are four C-160 Transall, one CL-601 Challenger and two Airbus A310, which, if necessary, can be equipped with one or more intensive-care "patient transportation units" (PTU). Contrary to the two other aircrafts, the CL-601 Challenger is only equipped for the intensive-care transport of one individual patient. The PTU corresponds to the technical equipment of the intensive care unit of a level-1-trauma centre and ensures an intensive-care therapy on highest level also during longer transportation. The work with this equipment, the characteristics of the long-distance air transport and the special situation of the military deployment causes special demands on the qualifications of the assigned personnel. Primarily planned for the repatriation of injured or ill soldiers, in the mean time, this concept is also essential for the medevac of civilian victims after mass casualties worldwide.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Paul T.
2006-01-06
Although cross-sectional studies show active individuals areleaner than their sedentary counterparts, it remains to be determined towhat extent this is due to initially leaner men and women choosing toexercise longer and more intensely (self-selection bias). In this reportwalking volume (weekly distance) and intensity (speed) were compared tocurrent BMI (BMIcurrent) and BMI at the start of walking (BMIstarting) in20,353 women and 5,174 men who had walked regularly for exercise for 7.2and 10.6 years,respectively. The relationships of BMIcurrent andBMIstarting with distance and intensity were nonlinear (convex). Onaverage, BMIstarting explained>70 percent of the association betweenBMIcurrent and intensity, and 40 percent and 17 percentmore » of theassociation between BMIcurrent and distance in women and men,respectively. Although the declines in BMIcurrent with distance andintensity were greater among fatter than leaner individuals, the portionsattributable to BMIstarting remained relatively constant regardless offatness. Thus self-selection bias accounts for most of the decline in BMIwith walking intensity and smaller albeit significant proportions of thedecline with distance. This demonstration of self-selection is germane toother cross-sectional comparisons in epidemiological research, givenself-selection is unlikely to be limited to weight or peculiar tophysical activity.« less
Norton, J L; Jackson, K; Chen, J W; Boston, R; Nolen-Walston, R D
2013-01-01
Pneumonia is observed in horses after long-distance transportation in association with confinement of head position leading to reduction in tracheal mucociliary clearance rate (TMCR). Clenbuterol, a beta-2 agonist shown to increase TMCR in the horse, will ameliorate the effects of a fixed elevated head position on large airway contamination and inflammation in a model of long-distance transportation model. Six adult horses. A cross-over designed prospective study. Horses were maintained with a fixed elevated head position for 48 hours to simulate long-distance transport, and treated with clenbuterol (0.8 μg/kg PO q12h) or a placebo starting 12 hours before simulated transportation. TMCR was measured using a charcoal clearance technique. Data were collected at baseline and 48 hours, and included TMCR, tracheal wash cytology and quantitative culture, rectal temperature, CBC, fibrinogen, and serum TNFα, IL-10, and IL-2 levels. There was a 18-21 day washout between study arms, and data were analyzed using regression analysis and Wilcoxon rank-sum tests. Tracheal mucociliary clearance rate was significantly decreased after transportation in both treatment (P = .002) and placebo (P = .03) groups. There was a significant effect of treatment on TMCR, with the treatment group showing half the reduction in TMCR compared with the placebo group (P = .002). Other significant differences between before- and after-transportation samples occurred for serum fibrinogen, peripheral eosinophil count, quantitative culture, tracheal bacteria, and degenerate neutrophils, though no treatment effect was found. Treatment with clenbuterol modestly attenuates the deleterious effects of this long-distance transportation model on tracheal mucociliary clearance. Copyright © 2013 by the American College of Veterinary Internal Medicine.
Vacuolar sequestration capacity and long-distance metal transport in plants
Peng, Jia-Shi; Gong, Ji-Ming
2014-01-01
The vacuole is a pivotal organelle functioning in storage of metabolites, mineral nutrients, and toxicants in higher plants. Accumulating evidence indicates that in addition to its storage role, the vacuole contributes essentially to long-distance transport of metals, through the modulation of Vacuolar sequestration capacity (VSC) which is shown to be primarily controlled by cytosolic metal chelators and tonoplast-localized transporters, or the interaction between them. Plants adapt to their environments by dynamic regulation of VSC for specific metals and hence targeting metals to specific tissues. Study of VSC provides not only a new angle to understand the long-distance root-to-shoot transport of minerals in plants, but also an efficient way to biofortify essential mineral nutrients or to phytoremediate non-essential metal pollution. The current review will focus on the most recent proceedings on the interaction mechanisms between VSC regulation and long-distance metal transport. PMID:24550927
Vacuolar sequestration capacity and long-distance metal transport in plants.
Peng, Jia-Shi; Gong, Ji-Ming
2014-01-01
The vacuole is a pivotal organelle functioning in storage of metabolites, mineral nutrients, and toxicants in higher plants. Accumulating evidence indicates that in addition to its storage role, the vacuole contributes essentially to long-distance transport of metals, through the modulation of Vacuolar sequestration capacity (VSC) which is shown to be primarily controlled by cytosolic metal chelators and tonoplast-localized transporters, or the interaction between them. Plants adapt to their environments by dynamic regulation of VSC for specific metals and hence targeting metals to specific tissues. Study of VSC provides not only a new angle to understand the long-distance root-to-shoot transport of minerals in plants, but also an efficient way to biofortify essential mineral nutrients or to phytoremediate non-essential metal pollution. The current review will focus on the most recent proceedings on the interaction mechanisms between VSC regulation and long-distance metal transport.
NASA Astrophysics Data System (ADS)
Ji, Yanling; Duan, Tao; Zhou, Weimin; Li, Boyuan; Wu, Fengjuan; Zhang, Zhimeng; Ye, Bin; Wang, Rong; Wu, Chunrong; Tang, Yongjian
2018-02-01
An enhanced long-distance transport of periodic electron beams in an advanced double layer cone-channel target is investigated using two-dimensional particle-in-cell simulations. The target consists of a cone attached to a double-layer hollow channel with a near-critical-density inner layer. The periodic electron beams are generated by the combination of ponderomotive force and longitudinal laser electric field. Then a stable electron propagation is achieved in the double-layer channel over a much longer distance without evident divergency, compared with a normal cone-channel target. Detailed simulations show that the much better long-distance collimation and guidance of energetic electrons is attributed to the much stronger electromagnetic fields at the inner wall surfaces. Furthermore, a continuous electron acceleration is obtained by the more intense laser electric fields and extended electron acceleration length in the channel. Our investigation shows that by employing this advanced target, both the forward-going electron energy flux in the channel and the energy coupling efficiency from laser to electrons are about threefold increased in comparison with the normal case.
Long-distance transport of phytohormones through the plant vascular system.
Lacombe, Benoit; Achard, Patrick
2016-12-01
Phytohormones are a group of low abundance molecules that activate various metabolic and developmental processes in response to environmental and endogenous signals. Like animal hormones, plant hormones often have distinct source and target tissues, hence ensuring long-range communication at the whole-plant level. Plants rely on various hormone distribution mechanisms depending on the distance and the direction of the transport. Here, we highlight the recent findings on the long-distance movement of plant hormones within the vasculature, from the physiological role to the molecular mechanism of the transport. Copyright © 2016 Elsevier Ltd. All rights reserved.
X-ray beam transfer between hollow fibers for long-distance transport
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tanaka, Yoshihito, E-mail: tanaka@sci.u-hyogo.ac.jp; Matsushita, Ryuki; Shiraishi, Ryutaro
2016-07-27
Fiber optics for controlling the x-ray beam trajectory has been examined at the synchrotron facility of SPring-8. Up to now, we have achieved beam deflection by several tens of milli-radian and axis shift of around 75 mm with a 1.5 m-long flexible hollow glass capillary. The achievable beam deflecting angle, axis shift, and timing delay are, in principle, proportional to the length, the square of length and the cube of length, respectively. Thus, for further applications, requiring larger beam shift and pulse delay, longer fibers are indispensable. In order to achieve long-distance transport using the fiber, we thus examined themore » connection transferring x-rays between fibers in an experimental hutch. The acceptance angle at the input end and the throughput efficiency of the second fiber is consistent with the consideration of the output beam divergence of the first fiber. The enhancement of the transfer efficiency is also discussed for the cases of a closer joint and the use of a refractive lens as a coupler.« less
Long-distance electron transport occurs globally in marine sediments
NASA Astrophysics Data System (ADS)
Burdorf, Laurine D. W.; Tramper, Anton; Seitaj, Dorina; Meire, Lorenz; Hidalgo-Martinez, Silvia; Zetsche, Eva-Maria; Boschker, Henricus T. S.; Meysman, Filip J. R.
2017-02-01
Recently, long filamentous bacteria have been reported conducting electrons over centimetre distances in marine sediments. These so-called cable bacteria perform an electrogenic form of sulfur oxidation, whereby long-distance electron transport links sulfide oxidation in deeper sediment horizons to oxygen reduction in the upper millimetres of the sediment. Electrogenic sulfur oxidation exerts a strong impact on the local sediment biogeochemistry, but it is currently unknown how prevalent the process is within the seafloor. Here we provide a state-of-the-art assessment of its global distribution by combining new field observations with previous reports from the literature. This synthesis demonstrates that electrogenic sulfur oxidation, and hence microbial long-distance electron transport, is a widespread phenomenon in the present-day seafloor. The process is found in coastal sediments within different climate zones (off the Netherlands, Greenland, the USA, Australia) and thrives on a range of different coastal habitats (estuaries, salt marshes, mangroves, coastal hypoxic basins, intertidal flats). The combination of a widespread occurrence and a strong local geochemical imprint suggests that electrogenic sulfur oxidation could be an important, and hitherto overlooked, component of the marine cycle of carbon, sulfur and other elements.
Effect of long-distance transportation on serum metabolic profiles of steer calves.
Takemoto, Satoshi; Tomonaga, Shozo; Funaba, Masayuki; Matsui, Tohru
2017-12-01
Long-distance transportation is sometimes inevitable in the beef industry because of the geographic separation of major breeding and fattening areas. Long-distance transportation negatively impacts production and health of cattle, which may, at least partly, result from the disturbance of metabolism during and after transportation. However, alteration of metabolism remains elusive in transported cattle. We investigated the effects of transportation on the metabolomic profiles of Holstein steer calves. Non-targeted analysis of serum concentrations of low molecular weight metabolites was performed by gas chromatography mass spectrometry. Transportation affected 38 metabolites in the serum. A pathway analysis suggested that 26, 10, and 10 pathways were affected immediately after transportation, and 3 and 7 days after transportation, respectively. Some pathways were disturbed only immediately after transportation, likely because of feed and water withdrawal during transit. Nicotinate and nicotinamide metabolism, and citric acid cycle were affected for 3 days after transportation, whereas propionate metabolism, phenylalanine and tyrosine metabolism were affected throughout the experiment. Four pathways were not affected immediately after transportation, but were altered thereafter. These results suggested that many metabolic pathways had marked perturbations during transportation. Metabolites such as citric acid, propionate, tyrosine and niacin can be candidate supplements for mitigating transportation-induced adverse effects. © 2017 Japanese Society of Animal Science.
ERIC Educational Resources Information Center
Durkop, Brooke R.; Jasek, Debbie; Kuhn, Beverly T.
The feasibility and sustainability of a distance learning program at the Texas Transportation Institute, which is part of the Texas A&M University system, was investigated. A literature review and online survey of current transportation professionals were conducted to examine the market potential for a distance learning program and to identify…
Particle transport patterns of short-distance soil erosion by wind-driven rain, rain and wind
NASA Astrophysics Data System (ADS)
Marzen, Miriam; Iserloh, Thomas; de Lima, João L. M. P.; Ries, Johannes B.
2015-04-01
Short distance erosion of soil surface material is one of the big question marks in soil erosion studies. The exact measurement of short-distance transported soil particles, prior to the occurrence of overland flow, is a challenge to soil erosion science due to the particular requirements of the experimental setup and test procedure. To approach a quantification of amount and distance of each type of transport, we applied an especially developed multiple-gutter system installed inside the Trier Portable Wind and Rainfall Simulator (PWRS). We measured the amount and travel distance of soil particles detached and transported by raindrops (splash), wind-driven rain (splash-saltation and splash-drift) and wind (saltation). The test setup included three different erosion agents (rain/ wind-driven rain/ wind), two substrates (sandy/ loamy), three surface structures (grain roughness/ rills lengthwise/ rills transversal) and three slope angles (0°/+7°/-7°). The results present detailed transport patterns of the three erosion agents under the varying soil and surface conditions up to a distance of 1.6 m. Under the applied rain intensity and wind velocity, wind-driven rain splash generates the highest erosion. The erodibility and travel distance of the two substrates depend on the erosion agent. The total erosion is slightly higher for the slope angle -7° (downslope), but for wind-driven rain splash, the inclination is not a relevant factor. The effect of surface structures (rills) changes with traveling distance. The wind driven rain splash generates a much higher amount of erosion and a further travel distance of the particles due to the combined action of wind and rain. The wind-driven rain factor appears to be much more significant than the other factors. The study highlights the effects of different erosion agents and surface parameters on short-distance particle transport and the powerful impact of wind-driven rain on soil erosion.
Laaksonen, Sauli; Jokelainen, Pikka; Pusenius, Jyrki; Oksanen, Antti
2017-03-15
Slaughter reindeer are exposed to stress caused by gathering, handling, loading and unloading, and by conditions in vehicles during transport. These stress factors can lead to compromised welfare and trauma such as bruises or fractures, aspiration of rumen content, and abnormal odour in carcasses, and causing condemnations in meat inspection and lower meat quality. We investigated the statistical association of slaughter transport distance with these indices using meat inspection data from years 2004-2016, including inspection of 669,738 reindeer originating from Finnish reindeer herding areas. Increased stress and decreased welfare of reindeer, as indicated by higher incidence of carcass condemnation due to bruises or fractures, aspiration of rumen content, or abnormal odour, were positively associated with systems involving shorter transport distances to abattoirs. Significant differences in incidence of condemnations were also detected between abattoirs and reindeer herding cooperatives. This study indicates that in particular the short-distance transports of reindeer merit more attention. While the results suggest that factors associated with long distance transport, such as driver education, truck design, veterinary supervision, and specialist equipment, may be favourable to reducing pre-slaughter stress in reindeer when compared with short distance transport systems, which occur in a variety of vehicle types and may be done by untrained handlers. Further work is required to elucidate the causal factors to the current results.
NASA Astrophysics Data System (ADS)
Schneider, Johannes M.; Turowski, Jens M.; Rickenmann, Dieter; Hegglin, Ramon; Arrigo, Sabrina; Mao, Luca; Kirchner, James W.
2014-03-01
Bed load transport during storm events is both an agent of geomorphic change and a significant natural hazard in mountain regions. Thus, predicting bed load transport is a central challenge in fluvial geomorphology and natural hazard risk assessment. Bed load transport during storm events depends on the width and depth of bed scour, as well as the transport distances of individual sediment grains. We traced individual gravels in two steep mountain streams, the Erlenbach (Switzerland) and Rio Cordon (Italy), using magnetic and radio frequency identification tags, and measured their bed load transport rates using calibrated geophone bed load sensors in the Erlenbach and a bed load trap in the Rio Cordon. Tracer transport distances and bed load volumes exhibited approximate power law scaling with both the peak stream power and the cumulative stream energy of individual hydrologic events. Bed load volumes scaled much more steeply with peak stream power and cumulative stream energy than tracer transport distances did, and bed load volumes scaled as roughly the third power of transport distances. These observations imply that large bed load transport events become large primarily by scouring the bed deeper and wider, and only secondarily by transporting the mobilized sediment farther. Using the sediment continuity equation, we can estimate the mean effective thickness of the actively transported layer, averaged over the entire channel width and the duration of individual flow events. This active layer thickness also followed approximate power law scaling with peak stream power and cumulative stream energy and ranged up to 0.57 m in the Erlenbach, broadly consistent with independent measurements.
Hahn, Steffen; Korner-Nievergelt, Fränzi; Emmenegger, Tamara; Amrhein, Valentin; Csörgő, Tibor; Gursoy, Arzu; Ilieva, Mihaela; Kverek, Pavel; Pérez-Tris, Javier; Pirrello, Simone; Zehtindjiev, Pavel; Salewski, Volker
2016-01-01
In migratory birds, morphological adaptations for efficient migratory flight often oppose morphological adaptations for efficient behavior during resident periods. This includes adaptations in wing shape for either flying long distances or foraging in the vegetation and in climate-driven variation of body size. In addition, the timing of migratory flights and particularly the timely arrival at local breeding sites is crucial because fitness prospects depend on site-specific phenology. Thus, adaptations for efficient long-distance flights might be also related to conditions at destination areas. For an obligatory long-distance migrant, the common nightingale, we verified that wing length as the aerodynamically important trait, but not structural body size increased from the western to the eastern parts of the species range. In contrast with expectation from aerodynamic theory, however, wing length did not increase with increasing migration distances. Instead, wing length was associated with the phenology at breeding destinations, namely the speed of local spring green-up. We argue that longer wings are beneficial for adjusting migration speed to local conditions for birds breeding in habitats with fast spring green-up and thus short optimal arrival periods. We suggest that the speed of spring green-up at breeding sites is a fundamental variable determining the timing of migration that fine tune phenotypes in migrants across their range.
Haag, Carl
2017-01-01
In highly polarised cells, like fungal hyphae, early endosomes function in both endocytosis as well as long-distance transport of various cargo including mRNA and protein complexes. However, knowledge on the crosstalk between these seemingly different trafficking processes is scarce. Here, we demonstrate that the ESCRT regulator Did2 coordinates endosomal transport in fungal hyphae of Ustilago maydis. Loss of Did2 results in defective vacuolar targeting, less processive long-distance transport and abnormal shuttling of early endosomes. Importantly, the late endosomal protein Rab7 and vacuolar protease Prc1 exhibit increased shuttling on these aberrant endosomes suggesting defects in endosomal maturation and identity. Consistently, molecular motors fail to attach efficiently explaining the disturbed processive movement. Furthermore, the endosomal mRNP linker protein Upa1 is hardly present on endosomes resulting in defects in long-distance mRNA transport. In conclusion, the ESCRT regulator Did2 coordinates precise maturation of endosomes and thus provides the correct membrane identity for efficient endosomal long-distance transport. PMID:28422978
DOT National Transportation Integrated Search
2013-03-01
The overall goal of this project is to enhance the fundamental understanding of Florida long-distance travel characteristics, and to provide policy implications for long-distance transportation planning in the future. To achieve the research goal, th...
Padalino, Barbara; Raidal, Sharanne Lee; Carter, Nicole; Celi, Pietro; Muscatello, Gary; Jeffcott, Leo; de Silva, Kumudika
2017-12-01
Horses are transported frequently and often over long distances. Transportation may represent a physiological stressor with consequential health and welfare implications. This study reports the effects of a long distance journey on immunological, clinical, haematological, inflammatory and oxidative parameters in an Experimental Group (EG) of ten horses, comparing them with six horses of similar age and breed used as a non-transported Control Group (CG). Clinical examination and blood sampling were performed twice on all horses: immediately after unloading for the EG, and at rest on the same day for the CG (day 1); at rest on the same day one week later for both groups (day 7). On day 1 EG horses showed increased heart and respiratory rates (P<0.01), rectal temperature (P<0.05), capillary refilling time (P<0.01), neutrophil numbers (P<0.01), serum albumin (P<0.01), plasma total antioxidant status (P<0.01), and a lower rate of mitogen induced proliferation of lymphocytes (P<0.05), in comparison with CG. On day 7 only an increase in total serum protein (P<0.05) and serum globulins (P<0.001) was seen in the EG. No difference in serum cortisol concentration was found. Long distance transportation induced an acute phase response impairing the cell-mediated immune response. Clinical examinations, including assessing CRT and body weight loss, and the monitoring of redox balance may be useful in evaluating the impact of extensive transport events on horses. A better understanding of the link between transportation stress, the immune system and the acute phase response is likely to inform strategies for enhancing the welfare of transported horses. Copyright © 2017 Elsevier Ltd. All rights reserved.
Multiple-Transportable Carbohydrate Effect on Long-Distance Triathlon Performance.
Rowlands, David S; Houltham, Stuart D
2017-08-01
The ingestion of multiple (2:1 glucose-fructose) transportable carbohydrate in beverages at high rates (>78 g·h) during endurance exercise enhances exogenous carbohydrate oxidation, fluid absorption, gut comfort, and performance relative to glucose alone. However, during long-distance endurance competition, athletes prefer a solid-gel-drink format, and the effect size of multiple-transportable carbohydrate is unknown. This study aimed to determine the effect of multiple-transportable carbohydrate on triathlon competition performance when ingested within bars, gels, and drinks. A double-blind randomized controlled trial was conducted within two national-body sanctioned half-ironman triathlon races held 3 wk apart in 74 well-trained male triathletes (18-60 yr; >2 yr competition experience). Carbohydrate comprising glucose/maltodextrin-fructose (2:1 ratio) or standard isocaloric carbohydrate (glucose/maltodextrin only) was ingested before (94 g) and during the cycle (2.5 g·km) and run (7.8 g·km) sections, averaging 78.6 ± 6.6 g·h, partitioned to bars (25%), gels (35%), and drink (40%). Postrace, 0- to 10-unit Likert-type scales were completed to assess gut comfort and energy. The trial returned low dropout rate (9%), high compliance, and sensitivity (typical error 2.2%). The effect of multiple-transportable carbohydrate on performance time was -0.53% (95% confidence interval = -1.30% to 0.24%; small benefit threshold = -0.54%), with likelihood-based risk analysis supporting adoption (benefit-harm ratio = 48.9%:0.3%; odds ratio = 285:1). Covariate adjustments for preexercise body weight and heat stress had negligible impact performance. Multiple-transportable carbohydrate possibly lowered nausea during the swim and bike; otherwise, effects on gut comfort and perceived energy were negligible. Multiple-transportable (2:1 maltodextrin/glucose-fructose) compared with single-transportable carbohydrate ingested in differing format provided a small benefit to long-distance
Neurotrophin Signaling via Long-Distance Axonal Transport
NASA Astrophysics Data System (ADS)
Chowdary, Praveen D.; Che, Dung L.; Cui, Bianxiao
2012-05-01
Neurotrophins are a family of target-derived growth factors that support survival, development, and maintenance of innervating neurons. Owing to the unique architecture of neurons, neurotrophins that act locally on the axonal terminals must convey their signals across the entire axon for subsequent regulation of gene transcription in the cell nucleus. This long-distance retrograde signaling, a motor-driven process that can take hours or days, has been a subject of intense interest. In the last decade, live-cell imaging with high sensitivity has significantly increased our capability to track the transport of neurotrophins, their receptors, and subsequent signals in real time. This review summarizes recent research progress in understanding neurotrophin-receptor interactions at the axonal terminal and their transport dynamics along the axon. We emphasize high-resolution studies at the single-molecule level and also discuss recent technical advances in the field.
Spatial pattern of long-distance symplasmic transport and communication in trees
Sokołowska, Katarzyna; Brysz, Alicja Maria; Zagórska-Marek, Beata
2013-01-01
Symplasmic short- and long-distance communication may be regulated at different levels of plant body organization. It depends on cell-to-cell transport modulated by plasmodesmata conductivity and frequency but above all on morphogenetic fields that integrate a plant at the supracellular level. Their control of physiological and developmental processes is especially important in trees, where the continuum consists of 3-dimensional systems of: 1) stem cells in cambium, and 2) living parenchyma cells in the secondary conductive tissues. We found that long-distance symplasmic transport in trees is spatially regulated. Uneven distribution of fluorescent tracer in cambial cells along the branches examined illustrates an unknown intrinsic phenomenon that can possibly be important for plant organism integration. Here we illustrate the spatial dynamics of symplasmic transport in cambium, test and exclude the role of callose in its regulation, and discuss the mechanism that could possibly be responsible for the maintenance of this spatial pattern. PMID:23989002
Mortality in rabbits transported for slaughter.
Voslarova, Eva; Vecerek, Vladimir; Bedanova, Iveta; Vecerkova, Lenka
2018-06-01
During transport rabbits may be exposed to various stressors which can compromise both their welfare and meat quality. Mortality related to the commercial transport of rabbits for slaughter was analyzed in the Czech Republic in the period from 2009 to 2016. The overall transport-related mortality of rabbits was 0.19%. Transport distance was found to have an impact on rabbit mortality; significantly (p < .001) greater losses were found in rabbits transported over longer distances. Mortality rates ranged from 0.02% in rabbits transported over distances of less than 50 km to 0.29% in rabbits transported over distances exceeding 400 km. A significantly (p < .001) increased risk was also associated with shipments in which 500 and more rabbits were delivered per batch. No effect of season was found. Our results show that rabbits can be transported within a wide range of temperatures (from -5 to 19.9°C) with no negative impact on mortality in transit. However, journeys carried out at temperatures below -5°C and above 20°C were associated with increased death losses (0.17% and 0.15%, respectively). © 2018 Japanese Society of Animal Science.
Metal species involved in long distance metal transport in plants
Álvarez-Fernández, Ana; Díaz-Benito, Pablo; Abadía, Anunciación; López-Millán, Ana-Flor; Abadía, Javier
2014-01-01
The mechanisms plants use to transport metals from roots to shoots are not completely understood. It has long been proposed that organic molecules participate in metal translocation within the plant. However, until recently the identity of the complexes involved in the long-distance transport of metals could only be inferred by using indirect methods, such as analyzing separately the concentrations of metals and putative ligands and then using in silico chemical speciation software to predict metal species. Molecular biology approaches also have provided a breadth of information about putative metal ligands and metal complexes occurring in plant fluids. The new advances in analytical techniques based on mass spectrometry and the increased use of synchrotron X-ray spectroscopy have allowed for the identification of some metal-ligand species in plant fluids such as the xylem and phloem saps. Also, some proteins present in plant fluids can bind metals and a few studies have explored this possibility. This study reviews the analytical challenges researchers have to face to understand long-distance metal transport in plants as well as the recent advances in the identification of the ligand and metal-ligand complexes in plant fluids. PMID:24723928
NASA Astrophysics Data System (ADS)
Métivier, L.; Brossier, R.; Mérigot, Q.; Oudet, E.; Virieux, J.
2016-04-01
Full waveform inversion using the conventional L2 distance to measure the misfit between seismograms is known to suffer from cycle skipping. An alternative strategy is proposed in this study, based on a measure of the misfit computed with an optimal transport distance. This measure allows to account for the lateral coherency of events within the seismograms, instead of considering each seismic trace independently, as is done generally in full waveform inversion. The computation of this optimal transport distance relies on a particular mathematical formulation allowing for the non-conservation of the total energy between seismograms. The numerical solution of the optimal transport problem is performed using proximal splitting techniques. Three synthetic case studies are investigated using this strategy: the Marmousi 2 model, the BP 2004 salt model, and the Chevron 2014 benchmark data. The results emphasize interesting properties of the optimal transport distance. The associated misfit function is less prone to cycle skipping. A workflow is designed to reconstruct accurately the salt structures in the BP 2004 model, starting from an initial model containing no information about these structures. A high-resolution P-wave velocity estimation is built from the Chevron 2014 benchmark data, following a frequency continuation strategy. This estimation explains accurately the data. Using the same workflow, full waveform inversion based on the L2 distance converges towards a local minimum. These results yield encouraging perspectives regarding the use of the optimal transport distance for full waveform inversion: the sensitivity to the accuracy of the initial model is reduced, the reconstruction of complex salt structure is made possible, the method is robust to noise, and the interpretation of seismic data dominated by reflections is enhanced.
Passive phloem loading and long-distance transport in a synthetic tree-on-a-chip.
Comtet, Jean; Jensen, Kaare H; Turgeon, Robert; Stroock, Abraham D; Hosoi, A E
2017-03-20
Vascular plants rely on differences in osmotic pressure to export sugars from regions of synthesis (mature leaves) to sugar sinks (roots, fruits). In this process, known as Münch pressure flow, the loading of sugars from photosynthetic cells to the export conduit (the phloem) is crucial, as it sets the pressure head necessary to power long-distance transport. Whereas most herbaceous plants use active mechanisms to increase phloem sugar concentration above that of the photosynthetic cells, in most tree species, for which transport distances are largest, loading seems, counterintuitively, to occur by means of passive symplastic diffusion from the mesophyll to the phloem. Here, we use a synthetic microfluidic model of a passive loader to explore the non-linear dynamics that arise during export and determine the ability of passive loading to drive long-distance transport. We first demonstrate that in our device, the phloem concentration is set by the balance between the resistances to diffusive loading from the source and convective export through the phloem. Convection-limited export corresponds to classical models of Münch transport, where the phloem concentration is close to that of the source; in contrast, diffusion-limited export leads to small phloem concentrations and weak scaling of flow rates with hydraulic resistance. We then show that the effective regime of convection-limited export is predominant in plants with large transport resistances and low xylem pressures. Moreover, hydrostatic pressures developed in our synthetic passive loader can reach botanically relevant values as high as 10 bars. We conclude that passive loading is sufficient to drive long-distance transport in large plants, and that trees are well suited to take full advantage of passive phloem loading strategies.
Molecular analysis confirms the long-distance transport of Juniperus ashei pollen
Mohanty, Rashmi Prava; Buchheim, Mark Alan; Anderson, James; Levetin, Estelle
2017-01-01
Although considered rare, airborne pollen can be deposited far from its place of origin under a confluence of favorable conditions. Temporally anomalous records of Cupressacean pollen collected from January air samples in London, Ontario, Canada have been cited as a new case of long-distance transport. Data on pollination season implicated Juniperus ashei (mountain cedar), with populations in central Texas and south central Oklahoma, as the nearest source of the Cupressacean pollen in the Canadian air samples. This finding is of special significance given the allergenicity of mountain cedar pollen. While microscopy is used extensively to identify particles in the air spora, pollen from all members of the Cupressaceae, including Juniperus, are morphologically indistinguishable. Consequently, we implemented a molecular approach to characterize Juniperus pollen using PCR in order to test the long-distance transport hypothesis. Our PCR results using species-specific primers confirmed that the anomalous Cupressacean pollen collected in Canada was from J. ashei. Forward trajectory analysis from source areas in Texas and the Arbuckle Mountains in Oklahoma and backward trajectory analysis from the destination area near London, Ontario were completed using models implemented in HYSPLIT4 (Hybrid Single-Particle Lagrangian Integrated Trajectory). Results from these trajectory analyses strongly supported the conclusion that the J. ashei pollen detected in Canada had its origins in Texas or Oklahoma. The results from the molecular findings are significant as they provide a new method to confirm the long-distance transport of pollen that bears allergenic importance. PMID:28273170
An Approach for Economic Analysis of Intermodal Transportation
Sahin, Bahri; Ust, Yasin; Guneri, Ali Fuat; Gulsun, Bahadir; Turan, Eda
2014-01-01
A different intermodal transportation model based on cost analysis considering technical, economical, and operational parameters is presented. The model consists of such intermodal modes as sea-road, sea-railway, road-railway, and multimode of sea-road-railway. A case study of cargo transportation has been carried out by using the suggested model. Then, the single road transportation mode has been compared to intermodal modes in terms of transportation costs. This comparison takes into account the external costs of intermodal transportation. The research reveals that, in the short distance transportation, single transportation modes always tend to be advantageous. As the transportation distance gets longer, intermodal transportation advantages begin to be effective on the costs. In addition, the proposed method in this study leads to determining the fleet size and capacity for transportation and the appropriate transportation mode. PMID:25152919
An approach for economic analysis of intermodal transportation.
Sahin, Bahri; Yilmaz, Huseyin; Ust, Yasin; Guneri, Ali Fuat; Gulsun, Bahadir; Turan, Eda
2014-01-01
A different intermodal transportation model based on cost analysis considering technical, economical, and operational parameters is presented. The model consists of such intermodal modes as sea-road, sea-railway, road-railway, and multimode of sea-road-railway. A case study of cargo transportation has been carried out by using the suggested model. Then, the single road transportation mode has been compared to intermodal modes in terms of transportation costs. This comparison takes into account the external costs of intermodal transportation. The research reveals that, in the short distance transportation, single transportation modes always tend to be advantageous. As the transportation distance gets longer, intermodal transportation advantages begin to be effective on the costs. In addition, the proposed method in this study leads to determining the fleet size and capacity for transportation and the appropriate transportation mode.
Improve forest inventory with access data-measure transport distance and cost to market.
Dennis P. Bradley
1972-01-01
Describes a method for relating forest inventory volumes to transport distances and costs. The process, originally developed in Sweden, includes a computer program that can be used to summarize volumes by transport costs per cord to specified delivery point. The method has many potential applications in all aspects of resource analysis.
Veldman, Alex; Diefenbach, Michael; Fischer, Doris; Benton, Alida; Bloch, Richard
2004-01-01
To illustrate the advantages and limitations of transporting ventilated intensive care unit patients over intercontinental distances on commercial airlines, this case series reports 8 ventilated patients repatriated by an air medical transport company. Eight ventilated patients, 3 suffering from internal and 5 from neurologic diseases. Distances ranged from 1700 to 10280 nautical miles with transport times from 04:10 hours to 21:55 hours. For 3 patients, a dedicated patient transport compartment (PTC) in the aircraft cabin was used. All patients were ventilator-dependent for a minimum of 11 days before transport (48 days median, 113 days maximum). One patient went into cardiac arrest during the flight and died. None of the other patients experienced any emergency or invasive procedures, other than peripheral venous access necessary during the flight. In all patients, ventilation was adjusted with respect to the blood gas analysis at least once during the transport. No technical failures or drop-outs occurred during the flights. None of the flights had to be diverted for technical or medical reasons. Long distance international transport of ventilated intensive care unit patients is an extremely cost intensive and logistically challenging task. In a certain subgroup of relatively stable ventilated patients, transport on commercial airlines offers advantages in terms of cost effectiveness and reduced transport time and acceleration/deceleration trauma as a result of multiple fuel stops.
Body temperature change and outcomes in patients undergoing long-distance air medical transport.
Nakajima, Mikio; Aso, Shotaro; Yasunaga, Hideo; Shirokawa, Masamitsu; Nakano, Tomotsugu; Miyakuni, Yasuhiko; Goto, Hideaki; Yamaguchi, Yoshihiro
2018-04-30
Short-distance air medical transport for adult emergency patients does not significantly affect patients' body temperature and outcomes. This study aimed to examine the influence of long-distance air medical transport on patients' body temperatures and the relationship between body temperature change and mortality. We retrospectively enrolled consecutive patients transferred via helicopter or plane from isolated islands to an emergency medical center in Tokyo, Japan between April 2010 and December 2016. Patients' average body temperature was compared before and after air transport using a paired t-test, and corrections between body temperature change and flight duration were calculated using Pearson's correlation coefficient. Multivariable logistic regression models were then used to examine the association between body temperature change and in-hospital mortality. Of 1253 patients, the median age was 72 years (interquartile range, 60-82 years) and median flight duration was 71 min (interquartile range, 54-93 min). In-hospital mortality was 8.5%, and average body temperature was significantly different before and after air transport (36.7 °C versus 36.3 °C; difference: -0.36 °C; 95% confidence interval, -0.30 to -0.42; p < 0.001). There was no correlation between body temperature change and flight duration (r = 0.025, p = 0.371). In-hospital death was significantly associated with (i) hyperthermia (>38.0 °C) or normothermia (36.0-37.9 °C) before air transport and hypothermia after air transport (odds ratio, 2.08; 95% confidence interval, 1.20-3.63; p = 0.009), and (ii) winter season (odds ratio, 2.15; 95% confidence interval, 1.08-4.27; p = 0.030). Physicians should consider body temperature change during long-distance air transport in patients with not only hypothermia but also normothermia or hyperthermia before air transport, especially in winter. Copyright © 2018 Elsevier Inc. All rights reserved.
USDA-ARS?s Scientific Manuscript database
In the present analysis various forms fuel from biomass and fossil sources, their mass and energy densities, and their break-even transportation distances to transport them effectively were analyzed. This study gives an insight on how many times more energy spent on transporting the fuels to differe...
Voslárová, Eva; Rubesová, Lenka; Vecerek, Vladimír; Pisteková, Vladimíra; Malena, Milan
2006-01-01
Failure to comply with animal welfare requirements during the transport of turkeys to the slaughterhouse increases stress in animals, which is manifested by increased mortality rate during transport. The numbers of turkeys that died during transport or soon after arrival may serve as an important parameter to indicate the level of animal welfare during transport of turkeys. The number of turkeys that died during transport to slaughterhouses in the Czech Republic in the period from 1997 to 2004 was investigated. The mortality rate found was 0.28% +/- 0.06% but varied with travel distance. The lowest mortality rate was found in case of travel distance below 50 km (0.18% +/- 0.08%) while long travel distances resulted in considerable increase in the mortality rates of turkeys (between 0.28% +/- 0.07 and 0.37% +/- 0.10%). The mortality rate of transported turkeys was also affected by the particular month of the year. Thus, the highest overall mortality rate occurred at long travel distances during winter months, i.e. in December (0.34% +/- 0.18%), January (0.32% +/- 0.06%), and February (0.36% +/- 0.07%). The comparison of individual years has shown a long-term trend towards a decrease in turkeys' mortality during transportation to slaughterhouses from 0.32% in 1998 to 0.20% in 2004. The decrease was statistically significant (Spearman's rank correlation coefficient r = -0.86, p < 0.01). This trend can be evaluated as positive.
NASA Astrophysics Data System (ADS)
Panoiu, M.; Panoiu, C.; Lihaciu, I. L.
2018-01-01
This research presents an adaptive neuro-fuzzy system which is used in the prediction of the distance between the pantograph and contact line of the electrical locomotives used in railway transportation. In railway transportation any incident that occurs in the electrical system can have major negative effects: traffic interrupts, equipment destroying. Therefore, a prediction as good as possible of such situations is very useful. In the paper was analyzing the possibility of modeling and prediction the variation of the distance between the pantograph and the contact line using intelligent techniques
Applying transport-distance specific SOC distribution to calibrate soil erosion model WaTEM
NASA Astrophysics Data System (ADS)
Hu, Yaxian; Heckrath, Goswin J.; Kuhn, Nikolaus J.
2016-04-01
Slope-scale soil erosion, transport and deposition fundamentally decide the spatial redistribution of eroded sediments in terrestrial and aquatic systems, which further affect the burial and decomposition of eroded SOC. However, comparisons of SOC contents between upper eroding slope and lower depositional site cannot fully reflect the movement of eroded SOC in-transit along hillslopes. The actual transport distance of eroded SOC is decided by its settling velocity. So far, the settling velocity distribution of eroded SOC is mostly calculated from mineral particle specific SOC distribution. Yet, soil is mostly eroded in form of aggregates, and the movement of aggregates differs significantly from individual mineral particles. This urges a SOC erodibility parameter based on actual transport distance distribution of eroded fractions to better calibrate soil erosion models. Previous field investigation on a freshly seeded cropland in Denmark has shown immediate deposition of fast settling soil fractions and the associated SOC at footslopes, followed by a fining trend at the slope tail. To further quantify the long-term effects of topography on erosional redistribution of eroded SOC, the actual transport-distance specific SOC distribution observed on the field was applied to a soil erosion model WaTEM (based on USLE). After integrating with local DEM, our calibrated model succeeded in locating the hotspots of enrichment/depletion of eroded SOC on different topographic positions, much better corresponding to the real-world field observation. By extrapolating into repeated erosion events, our projected results on the spatial distribution of eroded SOC are also adequately consistent with the SOC properties in the consecutive sample profiles along the slope.
Bacenetti, Jacopo; Lovarelli, Daniela; Ingrao, Carlo; Tricase, Caterina; Negri, Marco; Fiala, Marco
2015-10-01
In Europe, thanks to public subsidy, the production of electricity from anaerobic digestion (AD) of agricultural feedstock has considerably grown and several AD plants were built. When AD plants are concentrated in specific areas (e.g., Northern Italy), increases of feedstock' prices and transport distances can be observed. In this context, as regards low-energy density feedstock, the present research was designed to estimate the influence of the related long-distance transport on the environmental performances of the biogas-to-electricity process. For this purpose the following transport systems were considered: farm trailers and trucks. For small distances (<5 km), the whole plant silage shows the lowest impact; however, when distances increase, silages with higher energy density (even though characterised by lower methane production per hectare) become more environmentally sustainable. The transport by trucks achieves better environmental performances especially for distances greater than 25 km. Copyright © 2015 Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
2001-04-01
This research investigated the feasibility and sustainability of a distance learning program at the Texas : Transportation Institute through the Center for Professional Development. Through a literature review and : an on-line questionnaire completed...
Harada, Kazuhiro; Lee, Sangyoon; Lee, Sungchul; Bae, Seongryu; Anan, Yuya; Harada, Kenji; Shimada, Hiroyuki
2018-04-01
Although previous studies have shown that good access to public transportation is positively related with physical activity, the moderators of this relationship have not been explored sufficiently in older adults. It is possible that driving status could moderate this relationship. The present study examined whether the objectively measured distance between public transportation and the home was associated with physical activity levels, and whether this association was moderated by driving status among Japanese older adults. In this cross-sectional study, participants (n = 2,878) completed questionnaires and wore accelerometers for at least 7 days, to measure their average daily step counts and minutes spent engaging in moderate-to-vigorous physical activity. Road network distances between the home and the nearest bus stop or train station were measured using geographic information systems. Driving status was assessed using questionnaires. Multiple regression analyses stratified by driving status revealed that, among nondrivers, living further away from public transportation was associated with higher step counts (β = 0.08, p < .001) and moderate-to-vigorous physical activity (β = 0.06, p = .029). Among drivers, living closer to public transportation was significantly associated with higher moderate-to-vigorous physical activity levels (β = -0.05, p = .042). Despite the small effect sizes, the direction of the association between distance from public transportation and physical activity was different for current drivers and nondrivers. These findings imply that good access to public transportation does not positively relate with greater engagement in physical activity among nondriving older adults. Shorter distances to public transportation might reduce opportunities for engaging in physical activity for them. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Possibility of long-distance heat transport in weightlessness using supercritical fluids
NASA Astrophysics Data System (ADS)
Beysens, D.; Chatain, D.; Nikolayev, V. S.; Ouazzani, J.; Garrabos, Y.
2010-12-01
Heat transport over large distances is classically performed with gravity or capillarity driven heat pipes. We investigate here whether the “piston effect,” a thermalization process that is very efficient in weightlessness in compressible fluids, could also be used to perform long-distance heat transfer. Experiments are performed in a modeling heat pipe (16.5 mm long, 3 mm inner diameter closed cylinder), with nearly adiabatic polymethylmethacrylate walls and two copper base plates. The cell is filled with H2 near its gas-liquid critical point (critical temperature: 33 K). Weightlessness is achieved by submitting the fluid to a magnetic force that compensates gravity. Initially the fluid is isothermal. Then heat is sent to one of the bases with an electrical resistance. The instantaneous amount of heat transported by the fluid is measured at the other end. The data are analyzed and compared with a two-dimensional numerical simulation that allows an extrapolation to be made to other fluids (e.g., CO2 , with critical temperature of 300 K). The major result is concerned with the existence of a very fast response at early times that is only limited by the thermal properties of the cell materials. The yield in terms of ratio, injected or transported heat power, does not exceed 10-30% and is limited by the heat capacity of the pipe. These results are valid in a large temperature domain around the critical temperature.
Shelburne, Samuel A.; Fang, Han; Okorafor, Nnaja; Sumby, Paul; Sitkiewicz, Izabela; Keith, David; Patel, Payal; Austin, Celest; Graviss, Edward A.; Musser, James M.; Chow, Dar-Chone
2007-01-01
Study of the maltose/maltodextrin binding protein MalE in Escherichia coli has resulted in fundamental insights into the molecular mechanisms of microbial transport. Whether gram-positive bacteria employ a similar pathway for maltodextrin transport is unclear. The maltodextrin binding protein MalE has previously been shown to be key to the ability of group A Streptococcus (GAS) to colonize the oropharynx, the major site of GAS infection in humans. Here we used a multifaceted approach to elucidate the function and binding characteristics of GAS MalE. We found that GAS MalE is a central part of a highly efficient maltodextrin transport system capable of transporting linear maltodextrins that are up to at least seven glucose molecules long. Of the carbohydrates tested, GAS MalE had the highest affinity for maltotriose, a major breakdown product of starch in the human oropharynx. The thermodynamics and fluorescence changes induced by GAS MalE-maltodextrin binding were essentially opposite those reported for E. coli MalE. Moreover, unlike E. coli MalE, GAS MalE exhibited no specific binding of maltose or cyclic maltodextrins. Our data show that GAS developed a transport system optimized for linear maltodextrins longer than two glucose molecules that has several key differences from its well-studied E. coli counterpart. PMID:17259319
Transport Distance of Invertebrate Environmental DNA in a Natural River
Deiner, Kristy; Altermatt, Florian
2014-01-01
Environmental DNA (eDNA) monitoring is a novel molecular technique to detect species in natural habitats. Many eDNA studies in aquatic systems have focused on lake or ponds, and/or on large vertebrate species, but applications to invertebrates in river systems are emerging. A challenge in applying eDNA monitoring in flowing waters is that a species' DNA can be transported downstream. Whether and how far eDNA can be detected due to downstream transport remains largely unknown. In this study we tested for downstream detection of eDNA for two invertebrate species, Daphnia longispina and Unio tumidus, which are lake dwelling species in our study area. The goal was to determine how far away from the source population in a lake their eDNA could be detected in an outflowing river. We sampled water from eleven river sites in regular intervals up to 12.3 km downstream of the lake, developed new eDNA probes for both species, and used a standard PCR and Sanger sequencing detection method to confirm presence of each species' eDNA in the river. We detected D. longispina at all locations and across two time points (July and October); whereas with U. tumidus, we observed a decreased detection rate and did not detect its eDNA after 9.1 km. We also observed a difference in detection for this species at different times of year. The observed movement of eDNA from the source amounting to nearly 10 km for these species indicates that the resolution of an eDNA sample can be large in river systems. Our results indicate that there may be species' specific transport distances for eDNA and demonstrate for the first time that invertebrate eDNA can persist over relatively large distances in a natural river system. PMID:24523940
Long-distance transport of L-ascorbic acid in potato
Tedone, Luigi; Hancock, Robert D; Alberino, Salvatore; Haupt, Sophie; Viola, Roberto
2004-01-01
Background Following on from recent advances in plant AsA biosynthesis there is increasing interest in elucidating the factors contributing to the L-ascorbic acid (AsA) content of edible crops. One main objective is to establish whether in sink organs such as fruits and tubers, AsA is synthesised in situ from imported photoassimilates or synthesised in source tissues and translocated via the phloem. In the current work we test the hypothesis that long-distance transport is involved in AsA accumulation within the potato tuber, the most significant source of AsA in the European diet. Results Using the EDTA exudation technique we confirm the presence of AsA in the phloem of potato plants and demonstrate a correlation between changes in the AsA content of source leaves and that of phloem exudates. Comparison of carboxyflourescein and AgNO3 staining is suggestive of symplastic unloading of AsA in developing tubers. This hypothesis was further supported by the changes in AsA distribution during tuber development which closely resembled those of imported photoassimilates. Manipulation of leaf AsA content by supply of precursors to source leaves resulted in increased AsA content of developing tubers. Conclusion Our data provide strong support to the hypothesis that long-distance transport of AsA occurs in potato. We also show that phloem AsA content and AsA accumulation in sink organs can be directly increased via manipulation of AsA content in the foliage. We are now attempting to establish the quantitative contribution of imported AsA to overall AsA accumulation in developing potato tubers via transgenic approaches. PMID:15377389
Testing the Münch hypothesis of long distance phloem transport in plants.
Knoblauch, Michael; Knoblauch, Jan; Mullendore, Daniel L; Savage, Jessica A; Babst, Benjamin A; Beecher, Sierra D; Dodgen, Adam C; Jensen, Kaare H; Holbrook, N Michele
2016-06-02
Long distance transport in plants occurs in sieve tubes of the phloem. The pressure flow hypothesis introduced by Ernst Münch in 1930 describes a mechanism of osmotically generated pressure differentials that are supposed to drive the movement of sugars and other solutes in the phloem, but this hypothesis has long faced major challenges. The key issue is whether the conductance of sieve tubes, including sieve plate pores, is sufficient to allow pressure flow. We show that with increasing distance between source and sink, sieve tube conductivity and turgor increases dramatically in Ipomoea nil. Our results provide strong support for the Münch hypothesis, while providing new tools for the investigation of one of the least understood plant tissues.
Penner, Louis A; Guevarra, Darwin A.; Harper, Felicity W. K.; Taub, Jeffrey; Phipps, Sean; Albrecht, Terrance L.; Kross, Ethan
2015-01-01
Pediatric cancer caregivers are typically present at their child’s frequent, invasive treatments, and such treatments elicit substantial distress. Yet, variability exists in how even the most anxious caregivers cope. Here we examined one potential source of this variability: caregivers’ tendencies to self-distance when reflecting on their feelings surrounding their child’s treatments. We measured caregivers’ self-distancing and trait anxiety at baseline, anticipatory anxiety during their child’s treatment procedures, and psychological distress and avoidance three months later. Self-distancing buffered high (but not low) trait anxious caregivers against short- and long-term distress without promoting avoidance. These findings held when controlling for other buffers, highlighting the unique benefits of self-distancing. These results identify a coping process that buffers vulnerable caregivers against a chronic life stressor while also demonstrating the ecological validly of laboratory research on self-distancing. Future research is needed to explicate causality and the cognitive and physiological processes that mediate these results. PMID:27617183
Andersen, Tonni Grube; Nour-Eldin, Hussam Hassan; Fuller, Victoria Louise; Olsen, Carl Erik; Burow, Meike; Halkier, Barbara Ann
2013-01-01
Although it is essential for plant survival to synthesize and transport defense compounds, little is known about the coordination of these processes. Here, we investigate the above- and belowground source-sink relationship of the defense compounds glucosinolates in vegetative Arabidopsis thaliana. In vivo feeding experiments demonstrate that the glucosinolate transporters1 and 2 (GTR1 and GTR2), which are essential for accumulation of glucosinolates in seeds, are likely to also be involved in bidirectional distribution of glucosinolates between the roots and rosettes, indicating phloem and xylem as their transport pathways. Grafting of wild-type, biosynthetic, and transport mutants show that both the rosette and roots are able to synthesize aliphatic and indole glucosinolates. While rosettes constitute the major source and storage site for short-chained aliphatic glucosinolates, long-chained aliphatic glucosinolates are synthesized both in roots and rosettes with roots as the major storage site. Our grafting experiments thus indicate that in vegetative Arabidopsis, GTR1 and GTR2 are involved in bidirectional long-distance transport of aliphatic but not indole glucosinolates. Our data further suggest that the distinct rosette and root glucosinolate profiles in Arabidopsis are shaped by long-distance transport and spatially separated biosynthesis, suggesting that integration of these processes is critical for plant fitness in complex natural environments. PMID:23995084
Albanese, B.; Angermeier, P.L.; Gowan, C.
2003-01-01
Mark-recapture studies generate biased, or distance-weighted, movement data because short distances are sampled more frequently than long distances. Using models and field data, we determined how study design affects distance weighting and the movement distributions of stream fishes. We first modeled distance weighting as a function of recapture section length in an unbranching stream. The addition of an unsampled tributary to one of these models substantially increased distance weighting by decreasing the percentage of upstream distances that were sampled. Similarly, the presence of multiple tributaries in the field study resulted in severe bias. However, increasing recapture section length strongly affected distance weighting in both the model and the field study, producing a zone where the number of fish moving could be estimated with little bias. Subsampled data from the field study indicated that longer median (three of three species) and maximum distances (two of three species) can be detected by increasing the length of the recapture section. The effect was extreme for bluehead chub Nocomis leptocephalus, a highly mobile species, which exhibited a longer median distance (133 m versus 60 m), a longer maximum distance (1,144 m versus 708 m), and a distance distribution that differed in shape when the full (4,123-m recapture section) and subsampled (1,978-m recapture section) data sets were compared. Correction factors that adjust the observed number of movements to undersampled distances upwards and those to oversampled distances downwards could not mitigate the distance weighting imposed by the shorter recapture section. Future studies should identify the spatial scale over which movements can be accurately measured before data are collected. Increasing recapture section length a priori is far superior to using post hoc correction factors to reduce the influence of distance weighting on observed distributions. Implementing these strategies will be especially
Testing the Münch hypothesis of long distance phloem transport in plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Knoblauch, Michael; Knoblauch, Jan; Mullendore, Daniel L.
Long distance transport in plants occurs in sieve tubes of the phloem. The pressure flow hypothesis introduced by Ernst Münch in 1930 describes a mechanism of osmotically generated pressure differentials that are supposed to drive the movement of sugars and other solutes in the phloem, but this hypothesis has long faced major challenges. The key issue is whether the conductance of sieve tubes, including sieve plate pores, is sufficient to allow pressure flow. We show that with increasing distance between source and sink, sieve tube conductivity and turgor increases dramatically in Ipomoea nil. Our results provide strong support for themore » Münch hypothesis, while providing new tools for the investigation of one of the least understood plant tissues.« less
Testing the Münch hypothesis of long distance phloem transport in plants
Knoblauch, Michael; Knoblauch, Jan; Mullendore, Daniel L.; ...
2016-06-02
Long distance transport in plants occurs in sieve tubes of the phloem. The pressure flow hypothesis introduced by Ernst Münch in 1930 describes a mechanism of osmotically generated pressure differentials that are supposed to drive the movement of sugars and other solutes in the phloem, but this hypothesis has long faced major challenges. The key issue is whether the conductance of sieve tubes, including sieve plate pores, is sufficient to allow pressure flow. We show that with increasing distance between source and sink, sieve tube conductivity and turgor increases dramatically in Ipomoea nil. Our results provide strong support for themore » Münch hypothesis, while providing new tools for the investigation of one of the least understood plant tissues.« less
Fernström, A L; Sutian, W; Royo, F; Westlund, K; Nilsson, T; Carlsson, H-E; Paramastri, Y; Pamungkas, J; Sajuthi, D; Schapiro, S J; Hau, J
2008-11-01
persisted for a longer time after the simulated transport housing event than in the pair housed monkeys. Our data confirm that the transport of cynomolgus monkeys is stressful and suggest that it would be beneficial for the cynomolgus monkeys to be housed and transported in compatible pairs from the time they leave their group cages at the source country breeding facility until they arrive at their final laboratory destination in the country of use.
NASA Astrophysics Data System (ADS)
Lan, G.; Jiang, J.; Li, D. D.; Yi, W. S.; Zhao, Z.; Nie, L. N.
2013-12-01
The calculation of water-hammer pressure phenomenon of single-phase liquid is already more mature for a pipeline of uniform characteristics, but less research has addressed the calculation of slurry water hammer pressure in complex pipelines with slurry flows carrying solid particles. In this paper, based on the developments of slurry pipelines at home and abroad, the fundamental principle and method of numerical simulation of transient processes are presented, and several boundary conditions are given. Through the numerical simulation and analysis of transient processes of a practical engineering of long-distance slurry transportation pipeline system, effective protection measures and operating suggestions are presented. A model for calculating the water impact of solid and fluid phases is established based on a practical engineering of long-distance slurry pipeline transportation system. After performing a numerical simulation of the transient process, analyzing and comparing the results, effective protection measures and operating advice are recommended, which has guiding significance to the design and operating management of practical engineering of longdistance slurry pipeline transportation system.
Impact of Distance on Mode of Active Commuting in Chilean Children and Adolescents.
Rodríguez-Rodríguez, Fernando; Cristi-Montero, Carlos; Celis-Morales, Carlos; Escobar-Gómez, Danica; Chillón, Palma
2017-11-02
Active commuting could contribute to increasing physical activity. The objective of this study was to characterise patterns of active commuting to and from schools in children and adolescents in Chile. A total of 453 Chilean children and adolescents aged between 10 and 18 years were included in this study. Data regarding modes of commuting and commuting distance was collected using a validated questionnaire. Commuting mode was classified as active commuting (walking and/or cycling) or non-active commuting (car, motorcycle and/or bus). Commuting distance expressed in kilometres was categorised into six subgroups (0 to 0.5, 0.6 to 1, 1.1 to 2, 2.1 to 3, 3.1 to 5 and >5 km). Car commuting was the main mode for children (to school 64.9%; from school 51.2%) and adolescents (to school 50.2%; from school 24.7%). Whereas public bus commuting was the main transport used by adolescents to return from school. Only 11.0% and 24.8% of children and adolescents, respectively, walk to school. The proportion of children and adolescents who engage in active commuting was lower in those covering longer distances compared to a short distance. Adolescents walked to and from school more frequently than children. These findings show that non-active commuting was the most common mode of transport and that journey distances may influence commuting modes in children and adolescents.
Testing the Münch hypothesis of long distance phloem transport in plants
Knoblauch, Michael; Knoblauch, Jan; Mullendore, Daniel L; Savage, Jessica A; Babst, Benjamin A; Beecher, Sierra D; Dodgen, Adam C; Jensen, Kaare H; Holbrook, N Michele
2016-01-01
Long distance transport in plants occurs in sieve tubes of the phloem. The pressure flow hypothesis introduced by Ernst Münch in 1930 describes a mechanism of osmotically generated pressure differentials that are supposed to drive the movement of sugars and other solutes in the phloem, but this hypothesis has long faced major challenges. The key issue is whether the conductance of sieve tubes, including sieve plate pores, is sufficient to allow pressure flow. We show that with increasing distance between source and sink, sieve tube conductivity and turgor increases dramatically in Ipomoea nil. Our results provide strong support for the Münch hypothesis, while providing new tools for the investigation of one of the least understood plant tissues. DOI: http://dx.doi.org/10.7554/eLife.15341.001 PMID:27253062
Active transport improves the precision of linear long distance molecular signalling
NASA Astrophysics Data System (ADS)
Godec, Aljaž; Metzler, Ralf
2016-09-01
Molecular signalling in living cells occurs at low copy numbers and is thereby inherently limited by the noise imposed by thermal diffusion. The precision at which biochemical receptors can count signalling molecules is intimately related to the noise correlation time. In addition to passive thermal diffusion, messenger RNA and vesicle-engulfed signalling molecules can transiently bind to molecular motors and are actively transported across biological cells. Active transport is most beneficial when trafficking occurs over large distances, for instance up to the order of 1 metre in neurons. Here we explain how intermittent active transport allows for faster equilibration upon a change in concentration triggered by biochemical stimuli. Moreover, we show how intermittent active excursions induce qualitative changes in the noise in effectively one-dimensional systems such as dendrites. Thereby they allow for significantly improved signalling precision in the sense of a smaller relative deviation in the concentration read-out by the receptor. On the basis of linear response theory we derive the exact mean field precision limit for counting actively transported molecules. We explain how intermittent active excursions disrupt the recurrence in the molecular motion, thereby facilitating improved signalling accuracy. Our results provide a deeper understanding of how recurrence affects molecular signalling precision in biological cells and novel medical-diagnostic devices.
NASA Astrophysics Data System (ADS)
Most, S.; Nowak, W.; Bijeljic, B.
2014-12-01
Transport processes in porous media are frequently simulated as particle movement. This process can be formulated as a stochastic process of particle position increments. At the pore scale, the geometry and micro-heterogeneities prohibit the commonly made assumption of independent and normally distributed increments to represent dispersion. Many recent particle methods seek to loosen this assumption. Recent experimental data suggest that we have not yet reached the end of the need to generalize, because particle increments show statistical dependency beyond linear correlation and over many time steps. The goal of this work is to better understand the validity regions of commonly made assumptions. We are investigating after what transport distances can we observe: A statistical dependence between increments, that can be modelled as an order-k Markov process, boils down to order 1. This would be the Markovian distance for the process, where the validity of yet-unexplored non-Gaussian-but-Markovian random walks would start. A bivariate statistical dependence that simplifies to a multi-Gaussian dependence based on simple linear correlation (validity of correlated PTRW). Complete absence of statistical dependence (validity of classical PTRW/CTRW). The approach is to derive a statistical model for pore-scale transport from a powerful experimental data set via copula analysis. The model is formulated as a non-Gaussian, mutually dependent Markov process of higher order, which allows us to investigate the validity ranges of simpler models.
Allano, Marion; Labrecque, Olivia; Rodriguez Batista, Edisleidy; Beauchamp, Guy; Bédard, Christian; Lavoie, Jean-Pierre; Leclere, Mathilde
2016-08-01
The aim of this study was to determine the effects of short distance transportation on airway mucus, cytology and bacterial culture to identify potential biases in the diagnosis of airway diseases in referral centres. Eight healthy adult horses were studied using a prospective cross-over design. Mucus scores, tracheal wash (cytology, bacterial culture) and bronchoalveolar lavage fluid (BALF; cytology) were obtained while stabled and following 2.5 h transportation (with and without hay). Neutrophil counts, percentages and BALF neutrophilia frequency increased following transport without hay (P <0.05). No effect was observed on tracheal cytology and bacterial count (P > 0.05). BALF neutrophilia could develop solely as a result of transportation or due to interactions between repeated transports, ambient temperature, head position or other environmental factors. Copyright © 2016 Elsevier Ltd. All rights reserved.
Lutterodt, G; Basnet, M; Foppen, J W A; Uhlenbrook, S
2009-02-01
Bacteria properties play an important role in the transport of bacteria in groundwater, but their role, especially for longer transport distances (>0.5 m) has not been studied. Thereto, we studied the effects of cell surface hydrophobicity, outer surface potential (OSP), cell sphericity, motility, and Ag43 protein expression on the outer cell surface for a number of E. coli strains, obtained from the environment on their transport behavior in columns of saturated quartz sand of 5 m height in two solutions: demineralized (DI) water and artificial groundwater (AGW). In DI water, sticking efficiencies ranged between 0.1 and 0.4 at the column inlet, and then decreased with transport distance to 0.02-0.2. In AGW, sticking efficiencies were on average 1log-unit higher than those in DI (water). Bacteria motility and Ag43 expression affected attachment with a (high) statistical significance. In contrast, hydrophobicity, OSP and cell sphericity did not significantly correlate with sticking efficiency. However, for transport distances more than 0.33 m, the correlation between sticking efficiency, Ag43 expression, and motility became insignificant. We concluded that Ag43 and motility played an important role in E. coli attachment to quartz grain surfaces, and that the transport distance dependent sticking efficiency reductions were caused by motility and Ag43 expression variations within a population. The implication of our findings is that less motile bacteria with little or no Ag43 expression may travel longer distances once they enter groundwater environments. In future studies, the possible effect of bacteria surface structures, like fimbriae, pili and surface proteins on bacteria attachment need to be considered more systematically in order to arrive at more meaningful inter-population comparisons of the transport behavior of E. coli strains in aquifers.
The sediments transport outcome from granite
NASA Astrophysics Data System (ADS)
Petre, Maria
2014-05-01
A landscape can be characterized by natural elements but also by the activity of the people. The shape of the landscape depends on the nature's type of rocks which compose the subsoil and on their physical-chemical properties. The action of the atmospheric factors and the presence of the water at the surface of the Earth can also shape or reshape a landscape and create new elements of the landscape. The rocks who are shaped by natural agents like the water are transformed into small particles or sediments. After this process, they can be transported by the rivers and deposed in different spots on the river according to the size of the sediments. For instance, the sand and the gravels do not travel on the same distances. The sand can be transported on a long distance and deposed near the oceans or seas, while the gravels are not transported to far from the source area. Once the sediments are no longer transported by the water, they are forming sedimentary deposits and. The sedimentary deposits suffer some transformations: a compaction and a cementation which will form the sedimentary rocks.
Salama, N K G; Murray, A G; Rabe, B
2016-04-01
In the majority of salmon farming countries, production occurs in zones where practices are coordinated to manage disease agents such as Lepeophtheirus salmonis. To inform the structure of zones in specific systems, models have been developed accounting for parasite biology and system hydrodynamics. These models provide individual system farm relationships, and as such, it may be beneficial to produce more generalized principles for informing structures. Here, we use six different forcing scenarios to provide simulations from a previously described model of the Loch Linnhe system, Scotland, to assess the maximum dispersal distance of lice particles released from 12 sites transported over 19 day. Results indicate that the median distance travelled is 6.1 km from release site with <2.5% transported beyond 15 km, which occurs from particles originating from half of the release sites, with an absolute simulated distance of 36 km observed. This provides information suggesting that the disease management areas developed for infectious salmon anaemia control may also have properties appropriate for salmon lice management in Scottish coastal waters. Additionally, general numerical descriptors of the simulated relative lice abundance reduction with increased distance from release location are proposed. © 2015 Crown copyright. © 2015 John Wiley & Sons Ltd.
Impact of Distance on Mode of Active Commuting in Chilean Children and Adolescents
Cristi-Montero, Carlos; Escobar-Gómez, Danica; Chillón, Palma
2017-01-01
Active commuting could contribute to increasing physical activity. The objective of this study was to characterise patterns of active commuting to and from schools in children and adolescents in Chile. A total of 453 Chilean children and adolescents aged between 10 and 18 years were included in this study. Data regarding modes of commuting and commuting distance was collected using a validated questionnaire. Commuting mode was classified as active commuting (walking and/or cycling) or non-active commuting (car, motorcycle and/or bus). Commuting distance expressed in kilometres was categorised into six subgroups (0 to 0.5, 0.6 to 1, 1.1 to 2, 2.1 to 3, 3.1 to 5 and >5 km). Car commuting was the main mode for children (to school 64.9%; from school 51.2%) and adolescents (to school 50.2%; from school 24.7%). Whereas public bus commuting was the main transport used by adolescents to return from school. Only 11.0% and 24.8% of children and adolescents, respectively, walk to school. The proportion of children and adolescents who engage in active commuting was lower in those covering longer distances compared to a short distance. Adolescents walked to and from school more frequently than children. These findings show that non-active commuting was the most common mode of transport and that journey distances may influence commuting modes in children and adolescents. PMID:29099044
Torrey, S; Bergeron, R; Faucitano, L; Widowski, T; Lewis, N; Crowe, T; Correa, J A; Brown, J; Hayne, S; Gonyou, H W
2013-06-01
Transportation of pigs to slaughter has the potential to negatively impact animal welfare, particularly in hot temperatures and over long transport durations. The objective of this experiment was to determine if season and location within vehicle influenced the behavior of market-weight pigs during loading, transit, unloading, and lairage after a long-distance trip to slaughter. On a pot-belly truck, 1,170 pigs were transported (n = 195 pigs/wk in 7 experimental compartments) for 8 h to a commercial abattoir in summer (6 wk) and winter (5 wk). Pig behavior was observed at loading, in transit, at unloading, and in lairage. Handler intervention at loading was observed, and the time to load and unload was recorded. Although season did not (P = 0.91) affect loading time, more prods (P = 0.014) were necessary to load pigs in summer than winter. Loading in winter also tended to be longer (P = 0.071) into compartments involving internal ramps. In transit, more pigs (P = 0.025) were standing in winter compared with summer. Unloading took longer (P < 0.006) in winter than in summer and from compartments where pigs had to negotiate ramps and 180° turns. Furthermore, pigs in summer experienced more slipping (P = 0.032), falling (P = 0.004), overlapping (P < 0.001), and walking backward (P < 0.001) than pigs in winter. Pigs unloading from compartments with internal ramps slipped more (P < 0.0001) than other pigs. Season influenced latency to rest in lairage, with those transported in summer resting sooner (P < 0.0001) than those in winter. In conclusion, season and location within trucks differentially affect pig behavior before, during, and after long-distance transportation. Differences in lighting and temperature between seasons and the inclusion of internal ramps within vehicles may play important roles in the welfare of pigs transported to slaughter.
NASA Astrophysics Data System (ADS)
Craddock, R. A.; Needell, Z. A.; Rose, T. R.
2012-04-01
Overview: The chemical and physical characteristics of sedimentary material can provide valuable clues about transport processes, distance traveled, and provenance, all of which are aspects of Martian geography that we would like to better understand. For a typical sedimentary deposit on Earth, for example, it has been shown that the ratio of feldspar to quartz can be used to assess the maturity (or transport distance) of a terrestrial deposit, because feldspar is more vulnerable to weathering than quartz. Further, chemical analysis can also be used to determine potential sediment sources, and grain-size sorting can be used to distinguish aeolian sediments (typically well-sorted) from fluvial sediments (poorly sorted in high energy environments). It is also common to use the shapes of individual quartz particles to determine transport process and distance, all of which can help us better understand the history of a sample of sedimentary material and the geological processes that created and emplaced it. These traditional sedimentological concepts are now being applied to our interpretation of Martian surface materials. Sullivan et al. [2008], for example, used grain-size and shape to assess eolian processes and to qualify transport distances of deposits found at the Spirit landing site in Gusev Crater. Stockstill-Cahill et al. [62008 used variations in mineral abundances observed in multispectral data to determine the provenance of dark dunes found in Amazonis Planitia craters. While applying our understanding of terrestrial sedimentary materials to Martian surface materials is intuitively sound and logical, the problem is that most of our current understanding is based on sediments derived from felsic materials (e.g., granite) primarily because that is the composition of most of the landmass on the Earth. However, the Martian surface is composed primarily of mafic material, or basalt, which generates much different sedimentary particles as it weathers. Instead of
Garrison, Virginia; Lamothe, Paul; Morman, Suzette; Plumlee, Geoffrey S.; Gilkes, Robert; Prakongkep, Nattaporn
2010-01-01
The Sahara and Sahel lose billions of tons of eroded mineral soils annually to the Americas and Caribbean, Europe and Asia via atmospheric transport. African dust was collected from a dust source region (Mali, West Africa) and from downwind sites in the Caribbean [Trinidad-Tobago (TT) and U.S. Virgin Islands (VI)] and analysed for 32 trace-elements. Elemental composition of African dust samples was similar to that of average upper continental crust (UCC), with some enrichment or depletion of specific trace-elements. Pb enrichment was observed only in dust and dry deposition samples from the source region and was most likely from local use of leaded gasoline. Dust particles transported long-distances (VI and TT) exhibited increased enrichment of Mo and minor depletion of other elements relative to source region samples. This suggests that processes occurring during long-distance transport of dust produce enrichment/depletion of specific elements. Bioaccessibility of trace-metals in samples was tested in simulated human fluids (gastric and lung) and was found to be greater in downwind than source region samples, for some metals (e.g., As). The large surface to volume ratio of the dust particles (<2.5 µm) at downwind sites may be a factor.
Do Pediatric Teams Affect Outcomes of Injured Children Requiring Inter-hospital Transport?
Calhoun, Amanda; Keller, Martin; Shi, Junxin; Brancato, Celeste; Donovan, Kathy; Kraus, Diana; Leonard, Julie C
2017-01-01
Studies show that pediatric trauma centers produce better outcomes and reduced mortality for injured children. Yet, most children do not have timely access to a pediatric trauma center and require stabilization locally with subsequent transfer. Investigators have demonstrated that pediatric transport teams (PTT) improve outcomes for critically ill children; however, these studies did not differentiate outcomes for injured children. It may be that moderate to severely injured children actually fare worse with PTT due to slower transport times inherent to their remote locations and thus delays in important interventions. The purpose of this study was to determine if outcomes for injured children are affected by use of PTT for inter-hospital transfer. We conducted a retrospective chart review of 1,177 children transferred to a pediatric trauma center for injury care between March 1st, 2012 and December 31st, 2013. We compared children who were transported by PTT (ground/air) to those transported by ground advanced life support (ALS) and air critical care (ACC). We described patient characteristics and transport times. For PTT vs. ALS and ACC, we compared hospital length of stay (LOS), transport interventions and adverse events. 1,177 injured children were transferred by the following modes: 68% ALS, 13% ACC, 11% Ground PTT, and 9% Air PTT. Children transported by PTT were younger and had higher ISS and lower GCS scores. PTT had a longer total transport time, departure preparation time, and patient bedside time. After controlling for age, ISS, GCS, transport mode, distance, and time, we found no significant difference in LOS between PTT vs. ALS and ACC. A subgroup analysis of children with higher ISS scores demonstrated a 65% longer LOS for children transported by ACC vs. PTT. There were no differences between transport teams with regard to acidosis, hypocarbia or hypercarbia, or maintenance of tubes and lines. Children transported by PTT were younger and sicker (vs
Model-Based Design of Long-Distance Tracer Transport Experiments in Plants.
Bühler, Jonas; von Lieres, Eric; Huber, Gregor J
2018-01-01
Studies of long-distance transport of tracer isotopes in plants offer a high potential for functional phenotyping, but so far measurement time is a bottleneck because continuous time series of at least 1 h are required to obtain reliable estimates of transport properties. Hence, usual throughput values are between 0.5 and 1 samples h -1 . Here, we propose to increase sample throughput by introducing temporal gaps in the data acquisition of each plant sample and measuring multiple plants one after each other in a rotating scheme. In contrast to common time series analysis methods, mechanistic tracer transport models allow the analysis of interrupted time series. The uncertainties of the model parameter estimates are used as a measure of how much information was lost compared to complete time series. A case study was set up to systematically investigate different experimental schedules for different throughput scenarios ranging from 1 to 12 samples h -1 . Selected designs with only a small amount of data points were found to be sufficient for an adequate parameter estimation, implying that the presented approach enables a substantial increase of sample throughput. The presented general framework for automated generation and evaluation of experimental schedules allows the determination of a maximal sample throughput and the respective optimal measurement schedule depending on the required statistical reliability of data acquired by future experiments.
Experience(s) in Creating Distance Learning Texts
ERIC Educational Resources Information Center
Todd, Peter A.
2007-01-01
A combination of factors including longer working hours, emphasis on professional development, and increased access to the Internet have fuelled the current high demand for distance learning options in tertiary biology. Distance learner students come from a heterogeneous pool of ages, backgrounds and abilities and they require choice in how they…
Why Do Long-Distance Travelers Have Improved Pancreatectomy Outcomes?
Jindal, Manila; Zheng, Chaoyi; Quadri, Humair S; Ihemelandu, Chukwuemeka U; Hong, Young K; Smith, Andrew K; Dudeja, Vikas; Shara, Nawar M; Johnson, Lynt B; Al-Refaie, Waddah B
2017-08-01
Centralization of complex surgical care has led patients to travel longer distances. Emerging evidence suggested a negative association between increased travel distance and mortality after pancreatectomy. However, the reason for this association remains largely unknown. We sought to unravel the relationships among travel distance, receiving pancreatectomy at high-volume hospitals, delayed surgery, and operative outcomes. We identified 44,476 patients who underwent pancreatectomy for neoplasms between 2004 and 2013 at the reporting facility from the National Cancer Database. Multivariable analyses were performed to examine the independent relationships between increments in travel distance mortality (30-day and long-term survival) after adjusting for patient demographics, comorbidity, cancer stage, and time trend. We then examined how additional adjustment of procedure volume affected this relationship overall and among rural patients. Median travel distance to undergo pancreatectomy increased from 16.5 to 18.7 miles (p for trend < 0.001). Although longer travel distance was associated with delayed pancreatectomy, it was also related to higher odds of receiving pancreatectomy at a high-volume hospital and lower postoperative mortality. In multivariable analysis, difference in mortality among patients with varying travel distance was attenuated by adjustment for procedure volume. However, longest travel distance was still associated with a 77% lower 30-day mortality rate than shortest travel among rural patients, even when accounting for procedure volume. Our large national study found that the beneficial effect of longer travel distance on mortality after pancreatectomy is mainly attributable to increase in procedure volume. However, it can have additional benefits on rural patients that are not explained by volume. Distance can represent a surrogate for rural populations. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights
NASA Astrophysics Data System (ADS)
Agudelo, Jhoana; Arias, Paola A.; Vieira, Sara C.; Martínez, J. Alejandro
2018-06-01
Several studies have identified a recent lengthening of the dry season over the southern Amazon during the last three decades. Some explanations to this lengthening suggest the influence of changes in the regional circulation over the Atlantic and Pacific oceans, whereas others point to the influence of vegetation changes over the Amazon rainforest. This study aims to understand the implications of more frequent long dry seasons in this forest on atmospheric moisture transport toward northern South America and the Caribbean region. Using a semi-Langrangian model for water vapor tracking, results indicate that longer dry seasons in the southern Amazon relate to reductions of water vapor content over the southern and eastern Amazon basin, due to significant reductions of evaporation and recycled precipitation rates in these regions, especially during the transition from dry to wet conditions in the southern Amazon. On the other hand, longer dry seasons also relate to enhanced atmospheric moisture content over the Caribbean and northern South America regions, mainly due to increased contributions of water vapor from oceanic regions and the increase of surface moisture convergence over the equatorial region. This highlights the importance of understanding the relative role of regional circulation and local surface conditions on modulating water vapor transport toward continental regions.
Preferred viewing distance and screen angle of electronic paper displays.
Shieh, Kong-King; Lee, Der-Song
2007-09-01
This study explored the viewing distance and screen angle for electronic paper (E-Paper) displays under various light sources, ambient illuminations, and character sizes. Data analysis showed that the mean viewing distance and screen angle were 495 mm and 123.7 degrees. The mean viewing distances for Kolin Chlorestic Liquid Crystal display was 500 mm, significantly longer than Sony electronic ink display, 491 mm. Screen angle for Kolin was 127.4 degrees, significantly greater than that of Sony, 120.0 degrees. Various light sources revealed no significant effect on viewing distances; nevertheless, they showed significant effect on screen angles. The screen angle for sunlight lamp (D65) was similar to that of fluorescent lamp (TL84), but greater than that of tungsten lamp (F). Ambient illumination and E-paper type had significant effects on viewing distance and screen angle. The higher the ambient illumination was, the longer the viewing distance and the lesser the screen angle. Character size had significant effect on viewing distances: the larger the character size, the longer the viewing distance. The results of this study indicated that the viewing distance for E-Paper was similar to that of visual display terminal (VDT) at around 500 mm, but greater than normal paper at about 360 mm. The mean screen angle was around 123.7 degrees, which in terms of viewing angle is 29.5 degrees below horizontal eye level. This result is similar to the general suggested viewing angle between 20 degrees and 50 degrees below the horizontal line of sight.
Influence of water chemistry and travel distance on bacteriophage PRD-1 transport in a sandy aquifer
Blanford, W.J.; Brusseau, M.L.; Jim Yeh, T.-C.; Gerba, C.P.; Harvey, R.
2005-01-01
Experiments were conducted to evaluate the impact of groundwater chemistry and travel distance on the transport and fate behavior of PRD-1, a bacteriophage employed as a surrogate tracer for pathogenic enteric viruses. The experiments were conducted in the unconfined aquifer at the United States Geological Survey Cape Cod Toxic-Substances Hydrology Research Site in Falmouth, Massachusetts. The transport behavior of bromide (Br-) and PRD-1 were evaluated in a sewage-effluent contaminated zone and a shallower uncontaminated zone at this site. Several multilevel sampling devices located along a 13-m transect were used to collect vertically discrete samples to examine longitudinal and vertical variability of PRD-1 retardation and attenuation. The concentration of viable bacteriophage in the aqueous phase decreased greatly during the first few meters of transport. This decrease is attributed to a combination of colloid filtration (attachment) and inactivation. The removal was greater (10 -12 relative recovery) and occurred within the first meter for the uncontaminated zone, whereas it was lesser (10-9 relative recovery) and occurred over 4 m in the contaminated zone. The lesser removal observed for the contaminated zone is attributed to the influence of sorbed and dissolved organic matter, phosphate, and other anions, which are present in higher concentrations in the contaminated zone, on PRD-1 attachment. After the initial decrease, the aqueous PRD-1 concentrations remained essentially constant in both zones for the remainder of the tests (total travel distances of 13 m), irrespective of variations in geochemical properties within and between the two zones. The viable, mobile PRD-1 particles traveled at nearly the rate of bromide, which was used as a non-reactive tracer. The results of this study indicate that a small fraction of viable virus particles may persist in the aqueous phase and travel significant distances in the subsurface environment. ?? 2005 Elsevier Ltd
Selective functionalization of carbon nanotubes based upon distance traveled
NASA Technical Reports Server (NTRS)
Khare, Bishun N. (Inventor); Meyyappan, Meyya (Inventor)
2010-01-01
Method and system for functionalizing a collection of carbon nanotubes (CNTs). A selected precursor gas (e.g., H.sub.2 or NH.sub.3 or NF.sub.3 or F.sub.2 or CF.sub.4 or C.sub.nH.sub.m) is irradiated to provide a cold plasma of selected target particles, such as atomic H or F, in a first chamber. The target particles are directed toward an array of CNTs located in a second chamber while suppressing transport of ultraviolet radiation to the second chamber. A CNT array is functionalized with the target particles, at or below room temperature, to a point of saturation, in an exposure time interval no longer than about 30 sec. The predominant species that are deposited on the CNT array vary with the distance d measured along a path from the precursor gas to the CNT array; two or three different predominant species can be deposited on a CNT array for distances d=d1 and d=d2>d1 and d=d3>d2.
Long-distance transport of Gibberellic Acid Insensitive mRNA in Nicotiana benthamiana
2013-01-01
Background The Gibberellic Acid (GA) signal is governed by the GAI (Gibberellic Acid Insensitive) repressor, which is characterized by a highly conserved N-terminal DELLA domain. Deletion of the DELLA domain results in constitutive suppression of GA signaling. As the GAI transcript is transportable in phloem elements, a Δ-DELLA GAI (gai) transgenic stock plant can reduce the stature of a scion through transport of gai mRNA from the stock. However, little is known about the characteristics of a scion on a gai stock. Results Arabidopsis Δ-DELLA GAI (gai) was fused with a T7 epitope tag and expressed under the control of a companion cell-specific expression promoter, Commelina yellow mottle virus promoter (CoYMVp), to enhance transport in the phloem. The CoYMVp:Atgai-T7 (CgT) transgenic Nicotiana benthamiana exhibited a dwarf phenotype and lower sensitivity to GA enhancement of shoot stature. A wild-type (WT) scion on a CgT stock contained both Atgai-T7 mRNA and the translated product. Microarray analysis to clarify the effect of the CgT stock on the gene expression pattern in the scion clearly revealed that the WT scions on CgT stocks had fewer genes whose expression was altered in response to GA treatment. An apple rootstock variety, Malus prunifolia, integrating CoYMVp:Atgai moderately reduced the tree height of the apple cultivar scion. Conclusions Our results demonstrate that Atgai mRNA can move from companion cells to sieve tubes and that the translated product remains at the sites to which it is transported, resulting in attenuation of GA responses by reducing the expression of many genes. The induction of semi-dwarfism in an apple cultivar on root stock harbouring Atgai suggests that long-distance transport of mRNA from grafts would be applicable to horticulture crops. PMID:24144190
NASA Astrophysics Data System (ADS)
Onoyama, Takashi; Maekawa, Takuya; Kubota, Sen; Tsuruta, Setuso; Komoda, Norihisa
To build a cooperative logistics network covering multiple enterprises, a planning method that can build a long-distance transportation network is required. Many strict constraints are imposed on this type of problem. To solve these strict-constraint problems, a selfish constraint satisfaction genetic algorithm (GA) is proposed. In this GA, each gene of an individual satisfies only its constraint selfishly, disregarding the constraints of other genes in the same individuals. Moreover, a constraint pre-checking method is also applied to improve the GA convergence speed. The experimental result shows the proposed method can obtain an accurate solution in a practical response time.
NASA Astrophysics Data System (ADS)
Lin, Binbin; Ross, Shane D.; Prussin, Aaron J.; Schmale, David G.
2014-09-01
Spores of fungi in the genus Fusarium may be transported through the atmosphere over long distances. New information is needed to characterize seasonal trends in atmospheric loads of Fusarium and to pinpoint the source(s) of inoculum at both local (farm) and regional (state or country) scales. We hypothesized that (1) atmospheric concentrations of Fusarium spores in an agricultural ecosystem vary with height and season and (2) transport distances from potential inoculum source(s) vary with season. To test these hypotheses, spores of Fusarium were collected from the atmosphere in an agricultural ecosystem in Blacksburg, VA, USA using a Burkard volumetric sampler (BVS) 1 m above ground level and autonomous unmanned aerial vehicles (UAVs) 100 m above ground level. More than 2200 colony forming units (CFUs) of Fusarium were collected during 104 BVS sampling periods and 180 UAV sampling periods over four calendar years (2009-2012). Spore concentrations ranged from 0 to 13 and 0 to 23 spores m-3 for the BVS and the UAVs, respectively. Spore concentrations were generally higher in the fall, spring, and summer, and lower in the winter. Spore concentrations from the BVS were generally higher than those from the UAVs for both seasonal and hourly collections. A Gaussian plume transport model was used to estimate distances to the potential inoculum source(s) by season, and produced mean transport distances of 1.4 km for the spring, 1.7 km for the summer, 1.2 km for the fall, and 4.1 km for the winter. Environmental signatures that predict atmospheric loads of Fusarium could inform disease spread, air pollution, and climate change.
Fuller, Daniel; Cummins, Steven; Matthews, Stephen A
2013-01-01
A consistent body of research has shown that the neighborhood food environment is associated with fruit and vegetable (F&V) consumption and obesity in deprived neighborhoods in the United States. However, these studies have often neglected to consider how transportation can moderate associations between food accessibility and diet-related outcomes. This study examined associations between distance to primary food store, fruit and vegetable consumption, and BMI and whether mode of transportation to the primary food store moderates this relation. Cross-sectional data from the baseline wave of the Philadelphia Neighborhood Food Environment Study were used. A telephone survey of adult (≥18 y of age) household primary food shoppers residing in 2 Philadelphia neighborhoods was conducted (n = 1440). In a bivariate linear regression analysis, distance to primary food store did not predict F&V consumption (β = 0.04; 95% CI: -0.00, 0.09). Linear regression analysis stratified by transportation mode to the main F&V store showed no difference in F&V consumption between car, public, and multimodal transportation users. Compared with respondents using multimodal transportation, those using public transit had a significantly lower BMI (β = -1.31; 95% CI: -2.50, -0.10), whereas those using an automobile did not (β = -0.41; 95% CI: -1.36, 0.54). The assumption that using an automobile to access food stores results in increased F&V consumption was not confirmed. Significant associations were found for the relation between transportation mode and BMI. Theory-based mechanisms explaining relationships between the primary transportation mode used to access food stores and BMI should be further explored.
Prediction of distance in hammer throwing.
Dapena, Jesús; Gutiérrez-Dávila, Marcos; Soto, Víctor M; Rojas, Francisco J
2003-01-01
The aim of this study was to determine how much the predicted distance of a hammer throw is affected by (1) ignoring air resistance and (2) assuming that the centre of mass of the hammer coincides with the centre of the ball. Three-dimensional data from actual throws (men: 72.82 +/- 7.43 m; women: 67.78 +/- 4.02 m) were used to calculate the kinematic conditions of the hammer at release. A mathematical model of the hammer was then used to simulate the three-dimensional airborne motion of the hammer and to predict the distance of the throw. The distance predicted for vacuum conditions and using the ball centre to represent the hammer centre of mass was 4.30 +/- 2.64 m longer than the official distance of the throw for the men and 8.82 +/- 3.20 m longer for the women. Predictions using the true centre of mass of the hammer reduced the discrepancy to 2.39 +/- 2.58 m for the men and 5.28 +/- 2.88 m for the women. Predictions using air resistance and the true centre of mass of the hammer further reduced the discrepancy to -0.46 +/- 2.63 m for the men and 1.16 +/- 2.31 m for the women. Approximately half the loss of distance produced by air resistance was due to forces made on the ball and the remainder to forces made on the cable and handle. Equations were derived for calculation of the effects of air resistance and of the assumption that the centre of mass of the hammer coincides with the centre of the ball, on the distance of the throw.
Joseph, Benesh; Sikora, Arthur; Bordignon, Enrica; Jeschke, Gunnar; Cafiso, David S; Prisner, Thomas F
2015-05-18
Membrane proteins may be influenced by the environment, and they may be unstable in detergents or fail to crystallize. As a result, approaches to characterize structures in a native environment are highly desirable. Here, we report a novel general strategy for precise distance measurements on outer membrane proteins in whole Escherichia coli cells and isolated outer membranes. The cobalamin transporter BtuB was overexpressed and spin-labeled in whole cells and outer membranes and interspin distances were measured to a spin-labeled cobalamin using pulse EPR spectroscopy. A comparative analysis of the data reveals a similar interspin distance between whole cells, outer membranes, and synthetic vesicles. This approach provides an elegant way to study conformational changes or protein-protein/ligand interactions at surface-exposed sites of membrane protein complexes in whole cells and native membranes, and provides a method to validate outer membrane protein structures in their native environment. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Long wavelength perfect fluidity from short distance jet transport in quark-gluon plasmas
Xu, J.; Liao, J.; Gyulassy, M.
2015-12-01
Here, we build a new phenomenological framework that bridges the long wavelength bulk viscous transport properties of the strongly-coupled quark-gluon plasma (sQGP) and short distance hard jet transport properties in the QGP. The full nonperturbative chromo-electric (E) and chromo-magnetic (M) structure of the near “perfect fluid” like sQGP in the critical transition region are integrated into a semi-Quark-Gluon-Monopole Plasma (sQGMP) model lattice-compatibly and implemented into the new CUJET3.0 jet quenching framework. All observables computed from CUJET3.0 are found to be consistent with available data at RHIC and LHC simultaneously. Moreover, a quantitative connection between the shear viscosity and jet transportmore » parameter is rigorously established within this framework. Finally, we deduce the T = 160-600 MeV dependence of the QGP’s η/s: its near vanishing value in the near T c regime is determined by the composition of E and M charges, it increases as T rises, and its high T limit is fixed by color screening scales.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, Yi; Chen, Frank; Park, Joonkyu
Nanoscale phonon transport is a key process that governs thermal conduction in a wide range of materials and devices. Creating controlled phonon populations by resonant excitation at terahertz (THz) frequencies can drastically change the characteristics of nanoscale thermal transport and allow a direct real-space characterization of phonon mean-free paths. Using metamaterial-enhanced terahertz excitation, we tailored a phononic excitation by selectively populating low-frequency phonons within a nanoscale volume in a ferroelectric BaTiO3 thin film. Real-space time-resolved x-ray diffraction microscopy following THz excitation reveals ballistic phonon transport over a distance of hundreds of nm, two orders of magnitude longer than the averagedmore » phonon mean-free path in BaTiO3. On longer length scales, diffusive phonon transport dominates the recovery of the transient strain response, largely due to heat conduction into the substrate. The measured real-space phonon transport can be directly compared with the phonon mean-free path as predicted by molecular dynamics modeling. This time-resolved real-space visualization of THz-matter interactions opens up opportunities to engineer and image nanoscale transient structural states with new functionalities.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, Yi; Chen, Frank; Park, Joonkyu
Nanoscale phonon transport is a key process that governs thermal conduction in a wide range of materials and devices. Creating controlled phonon populations by resonant excitation at terahertz (THz) frequencies can drastically change the characteristics of nanoscale thermal transport and allow a direct real-space characterization of phonon mean-free paths. Using metamaterial-enhanced terahertz excitation, we tailored a phononic excitation by selectively populating low-frequency phonons within a nanoscale volume in a ferroelectric BaTiO 3 thin film. Real-space time-resolved x-ray diffraction microscopy following THz excitation reveals ballistic phonon transport over a distance of hundreds of nm, two orders of magnitude longer than themore » averaged phonon mean-free path in BaTiO 3. On longer length scales, diffusive phonon transport dominates the recovery of the transient strain response, largely due to heat conduction into the substrate. The measured real-space phonon transport can be directly compared with the phonon mean-free path as predicted by molecular dynamics modeling. In conclusion, this time-resolved real-space visualization of THz-matter interactions opens up opportunities to engineer and image nanoscale transient structural states with new functionalities.« less
Zhu, Yi; Chen, Frank; Park, Joonkyu; ...
2017-11-16
Nanoscale phonon transport is a key process that governs thermal conduction in a wide range of materials and devices. Creating controlled phonon populations by resonant excitation at terahertz (THz) frequencies can drastically change the characteristics of nanoscale thermal transport and allow a direct real-space characterization of phonon mean-free paths. Using metamaterial-enhanced terahertz excitation, we tailored a phononic excitation by selectively populating low-frequency phonons within a nanoscale volume in a ferroelectric BaTiO 3 thin film. Real-space time-resolved x-ray diffraction microscopy following THz excitation reveals ballistic phonon transport over a distance of hundreds of nm, two orders of magnitude longer than themore » averaged phonon mean-free path in BaTiO 3. On longer length scales, diffusive phonon transport dominates the recovery of the transient strain response, largely due to heat conduction into the substrate. The measured real-space phonon transport can be directly compared with the phonon mean-free path as predicted by molecular dynamics modeling. In conclusion, this time-resolved real-space visualization of THz-matter interactions opens up opportunities to engineer and image nanoscale transient structural states with new functionalities.« less
Role of Clay Minerals in Long-Distance Transport of Landslides in Valles Marineris, Mars
NASA Astrophysics Data System (ADS)
Watkins, J.; Ehlmann, B. L.; Yin, A.
2014-12-01
Long-runout (> 50 km) subaerial landslides are rare on Earth, but are common features episodically shaping Mars' Valles Marineris (VM) trough system over the past 3.5 billion years. They display two end-member morphologies: a thick-skinned inner zone, characterized by fault-bounded, rotated blocks near their source region, and a thin-skinned, exceptionally long-runout outer zone, characterized by thin sheets spreading over 10s of km across the trough floor. Four decades of studies on the latter have resulted in two main competing hypotheses to explain their long-distance transport: (1) movement of landslides over layers of trapped air or soft materials containing ice or snow, enabling basal lubrication, and (2) fluidization of landslide materials with or without the presence of water and volatiles. To address this issue, we examine the mineralogic composition of landslides across VM using Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) near-infrared spectral data analysis coupled with detailed geologic mapping and morphometric analysis of satellite images. Our survey reveals a general correlation between transport distance, significant lateral spreading, and the presence of hydrated silicates among VM landslides. Given that smectite clay absorbs water into its layered crystal structure and can reduce the friction coefficient by a factor of three v. that of dry rocks, these results suggest that hydrated silicates played a decisive role in facilitating long-runout landslide transport in VM. We propose that, concurrent with downslope failure and sliding of broken trough-wall rock, frontal landslide masses overrode and entrained hydrated-silicate-bearing trough-floor deposits, lubricating the basal sliding zones and permitting the landslide outer zones to spread laterally while moving forward over the low-friction surface. The key participation of hydrated silicates in episodic, sustained landslide activity throughout the canyon implies that clay minerals
Turbulent transport with intermittency: Expectation of a scalar concentration.
Rast, Mark Peter; Pinton, Jean-François; Mininni, Pablo D
2016-04-01
Scalar transport by turbulent flows is best described in terms of Lagrangian parcel motions. Here we measure the Eulerian distance travel along Lagrangian trajectories in a simple point vortex flow to determine the probabilistic impulse response function for scalar transport in the absence of molecular diffusion. As expected, the mean squared Eulerian displacement scales ballistically at very short times and diffusively for very long times, with the displacement distribution at any given time approximating that of a random walk. However, significant deviations in the displacement distributions from Rayleigh are found. The probability of long distance transport is reduced over inertial range time scales due to spatial and temporal intermittency. This can be modeled as a series of trapping events with durations uniformly distributed below the Eulerian integral time scale. The probability of long distance transport is, on the other hand, enhanced beyond that of the random walk for both times shorter than the Lagrangian integral time and times longer than the Eulerian integral time. The very short-time enhancement reflects the underlying Lagrangian velocity distribution, while that at very long times results from the spatial and temporal variation of the flow at the largest scales. The probabilistic impulse response function, and with it the expectation value of the scalar concentration at any point in space and time, can be modeled using only the evolution of the lowest spatial wave number modes (the mean and the lowest harmonic) and an eddy based constrained random walk that captures the essential velocity phase relations associated with advection by vortex motions. Preliminary examination of Lagrangian tracers in three-dimensional homogeneous isotropic turbulence suggests that transport in that setting can be similarly modeled.
Tang, Zhong; Fan, Xiaorong; Li, Qing; Feng, Huimin; Miller, Anthony J.; Shen, Qirong; Xu, Guohua
2012-01-01
Root nitrate uptake is well known to adjust to the plant’s nitrogen demand for growth. Long-distance transport and/or root storage pools are thought to provide negative feedback signals regulating root uptake. We have characterized a vascular specific nitrate transporter belonging to the high-affinity Nitrate Transporter2 (NRT2) family, OsNRT2.3a, in rice (Oryza sativa ssp. japonica ‘Nipponbare’). Localization analyses using protoplast expression, in planta promoter-β-glucuronidase assay, and in situ hybridization showed that OsNRT2.3a was located in the plasma membrane and mainly expressed in xylem parenchyma cells of the stele of nitrate-supplied roots. Knockdown expression of OsNRT2.3a by RNA interference (RNAi) had impaired xylem loading of nitrate and decreased plant growth at low (0.5 mm) nitrate supply. In comparison with the wild type, the RNAi lines contained both nitrate and total nitrogen significantly higher in the roots and lower in the shoots. The short-term [15N]NO3− influx (5 min) in entire roots and NO3− fluxes in root surfaces showed that the knockdown of OsNRT2.3a in comparison with the wild type did not affect nitrate uptake by roots. The RNAi plants showed no significant changes in the expression of some root nitrate transporters (OsNRT2.3b, OsNRT2.4, and OsNAR2.1), but transcripts for nia1 (nitrate reductase) had increased and OsNRT2.1 and OsNRT2.2 had decreased when the plants were supplied with nitrate. Taken together, the data demonstrate that OsNRT2.3a plays a key role in long-distance nitrate transport from root to shoot at low nitrate supply level in rice. PMID:23093362
NASA Astrophysics Data System (ADS)
de Weger, Letty A.; Pashley, Catherine H.; Šikoparija, Branko; Skjøth, Carsten A.; Kasprzyk, Idalia; Grewling, Łukasz; Thibaudon, Michel; Magyar, Donat; Smith, Matt
2016-12-01
The invasive alien species Ambrosia artemisiifolia (common or short ragweed) is increasing its range in Europe. In the UK and the Netherlands, airborne concentrations of Ambrosia pollen are usually low. However, more than 30 Ambrosia pollen grains per cubic metre of air (above the level capable to trigger allergic symptoms) were recorded in Leicester (UK) and Leiden (NL) on 4 and 5 September 2014. The aims of this study were to determine whether the highly allergenic Ambrosia pollen recorded during the episode could be the result of long distance transport, to identify the potential sources of these pollen grains and to describe the conditions that facilitated this possible long distance transport. Airborne Ambrosia pollen data were collected at 10 sites in Europe. Back trajectory and atmospheric dispersion calculations were performed using HYSPLIT_4. Back trajectories calculated at Leicester and Leiden show that higher altitude air masses (1500 m) originated from source areas on the Pannonian Plain and Ukraine. During the episode, air masses veered to the west and passed over the Rhône Valley. Dispersion calculations showed that the atmospheric conditions were suitable for Ambrosia pollen released from the Pannonian Plain and the Rhône Valley to reach the higher levels and enter the airstream moving to northwest Europe where they were deposited at ground level and recorded by monitoring sites. The study indicates that the Ambrosia pollen grains recorded during the episode in Leicester and Leiden were probably not produced by local sources but transported long distances from potential source regions in east Europe, i.e. the Pannonian Plain and Ukraine, as well as the Rhône Valley in France.
The visual perception of distance ratios outdoors.
Norman, J Farley; Adkins, Olivia C; Dowell, Catherine J; Shain, Lindsey M; Hoyng, Stevie C; Kinnard, Jonathan D
2017-05-01
We conducted an experiment to evaluate the ability of 32 younger and older adults to visually perceive distances in an outdoor setting. On any given trial, the observers viewed 2 environmental distances and were required to estimate the distance ratio-the length of the (usually) larger distance relative to that of the shorter. The stimulus distance ratios ranged from 1.0 (the stimulus distances were identical) to 8.0 (1 distance interval was 8.0 times longer than the other). The stimulus distances were presented within a 26 m × 60 m portion of a grassy field. The observers were able to reliably estimate the stimulus distance ratios: The overall Pearson r correlation coefficient relating the judged and actual distance ratios was 0.762. Fifty-eight percent of the variance in the observers' perceived distance ratios could thus be accounted for by variations in the actual stimulus ratios. About half of the observers significantly underestimated the distance ratios, while the judgments of the remainder were essentially accurate. Significant modulatory effects of sex and age occurred, such that the male observers' judgments were the most precise, while those of the older males were the most accurate.
Quantum transport of the single metallocene molecule
NASA Astrophysics Data System (ADS)
Yu, Jing-Xin; Chang, Jing; Wei, Rong-Kai; Liu, Xiu-Ying; Li, Xiao-Dong
2016-10-01
The Quantum transport of three single metallocene molecule is investigated by performing theoretical calculations using the non-equilibrium Green's function method combined with density functional theory. We find that the three metallocen molecules structure become stretched along the transport direction, the distance between two Cp rings longer than the other theory and experiment results. The lager conductance is found in nickelocene molecule, the main transmission channel is the electron coupling between molecule and the electrodes is through the Ni dxz and dyz orbitals and the s, dxz, dyz of gold. This is also confirmed by the highest occupied molecular orbital resonance at Fermi level. In addition, negative differential resistance effect is found in the ferrocene, cobaltocene molecules, this is also closely related with the evolution of the transmission spectrum under applied bias.
Issues of using Longer Heavier Vehicles on Roads
NASA Astrophysics Data System (ADS)
Matuszkova, R.; Heczko, M.; Cepil, J.; Radimsky, M.
2018-03-01
Many logistics companies aim to save on freight costs. Recently, not only on Czech roads and on motorways, longer and heavier vehicles that exceed dimensions’ limits appeared. For these vehicles, it is necessary to apply for a special permit, which is, however, much more liberal than the permit for oversized and overweight load transport. This paper informs about checking routes of these vehicles by swept path analysis and finding locations on roads that can generate both safety risks and traffic fluency problems.
Psychological distance of pedestrian at the bus terminal area
NASA Astrophysics Data System (ADS)
Firdaus Mohamad Ali, Mohd; Salleh Abustan, Muhamad; Hidayah Abu Talib, Siti; Abustan, Ismail; Rahman, Noorhazlinda Abd; Gotoh, Hitoshi
2018-03-01
Walking is a part of transportation modes that is effective for pedestrian in either short or long trips. All people are classified as pedestrian because people do walk every day and the higher number of people walking will lead to crowd conditions and that is the reason of the importance to study about the behaviour of pedestrian specifically the psychological distance in both indoor and outdoor. Nowadays, the number of studies of crowd dynamics among pedestrian have increased due to the concern about the safety issues primarily related to the emergency cases such as fire, earthquake, festival and etc. An observation of pedestrian was conducted at one of the main bus terminals in Kuala Lumpur with the main objective to obtain pedestrian psychological distance and it took place for 45 minutes by using a camcorder that was set up by using a tripod on the upper floor from the area of observation at the main lobby and the trapped area was approximately 100 m2. The analysis was focused on obtaining the gap between pedestrian based on two different categories, which are; (a) Pedestrian with relationship, and (b) Pedestrian without relationship. In total, 1,766 data were obtained during the analysis in which 561 data were obtained for `Pedestrian with relationship' and 1,205 data were obtained for "Pedestrian without relationship". Based on the obtained results, "Pedestrian without relationship" had shown a slightly higher average value of psychological distance between them compare to "Pedestrian with relationship" with the results of 1.6360m and 1.5909m respectively. In gender case, "Pedestrian without relationship" had higher mean of psychological distance in all three categories as well. Therefore, it can be concluded that pedestrian without relationship tend to have longer distance when walking in crowds.
Long-Distance Transport of Thiamine (Vitamin B1) Is Concomitant with That of Polyamines1[OPEN
Martinis, Jacopo; Gas-Pascual, Elisabet; Szydlowski, Nicolas; Crèvecoeur, Michèle; Gisler, Alexandra; Bürkle, Lukas; Fitzpatrick, Teresa B.
2016-01-01
Thiamine (vitamin B1) is ubiquitous and essential for cell energy supply in all organisms as a vital metabolic cofactor, known for over a century. In plants, it is established that biosynthesis de novo is taking place predominantly in green tissues and is furthermore limited to plastids. Therefore, transport mechanisms are required to mediate the movement of this polar metabolite from source to sink tissue to activate key enzymes in cellular energy generating pathways but are currently unknown. Similar to thiamine, polyamines are an essential set of charged molecules required for diverse aspects of growth and development, the homeostasis of which necessitates long-distance transport processes that have remained elusive. Here, a yeast-based screen allowed us to identify Arabidopsis (Arabidopsis thaliana) PUT3 as a thiamine transporter. A combination of biochemical, physiological, and genetic approaches permitted us to show that PUT3 mediates phloem transport of both thiamine and polyamines. Loss of function of PUT3 demonstrated that the tissue distribution of these metabolites is altered with growth and developmental consequences. The pivotal role of PUT3 mediated thiamine and polyamine homeostasis in plants, and its importance for plant fitness is revealed through these findings. PMID:27006489
The Effects of Age and Set Size on the Fast Extraction of Egocentric Distance
Gajewski, Daniel A.; Wallin, Courtney P.; Philbeck, John W.
2016-01-01
Angular direction is a source of information about the distance to floor-level objects that can be extracted from brief glimpses (near one's threshold for detection). Age and set size are two factors known to impact the viewing time needed to directionally localize an object, and these were posited to similarly govern the extraction of distance. The question here was whether viewing durations sufficient to support object detection (controlled for age and set size) would also be sufficient to support well-constrained judgments of distance. Regardless of viewing duration, distance judgments were more accurate (less biased towards underestimation) when multiple potential targets were presented, suggesting that the relative angular declinations between the objects are an additional source of useful information. Distance judgments were more precise with additional viewing time, but the benefit did not depend on set size and accuracy did not improve with longer viewing durations. The overall pattern suggests that distance can be efficiently derived from direction for floor-level objects. Controlling for age-related differences in the viewing time needed to support detection was sufficient to support distal localization but only when brief and longer glimpse trials were interspersed. Information extracted from longer glimpse trials presumably supported performance on subsequent trials when viewing time was more limited. This outcome suggests a particularly important role for prior visual experience in distance judgments for older observers. PMID:27398065
49 CFR 176.708 - Segregation distances.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 2 2011-10-01 2011-10-01 false Segregation distances. 176.708 Section 176.708... Requirements for Radioactive Materials § 176.708 Segregation distances. (a) Table IV lists minimum separation... into account any relocation of cargo during the voyage. (e) Any departure from the segregation...
Thornber, Peter M; Adams, David B
2008-01-01
Most Australian livestock are transported at some stage in their lives and the attendant risks must be managed. Like other countries, Australia has location-specific challenges for the land transport of animals that derive from general geography and history, quality of the road and rail systems, design of vehicles and handling facilities, competency and experience of drivers and livestock handlers, and pre- and post-journey management of animals. Australia is a large and sparsely populated country and requires a risk-based approach which builds on equivalent outcomes and performance criteria to ensure good welfare for animals during long distance transport. There are shared responsibilities by owners and service providers along the transport chain. Governments work closely with livestock industries, transporters, stock agents, sale yard operators, abattoir owners, feedlot owners and animal welfare organisations to develop and then apply sustainable animal welfare standards and appropriate regulations. The Australian Animal Welfare Strategy sets out a broad and inclusive forum for this to occur in a consultative and cooperative manner and with the necessary input from science. Animal welfare is protected through a combination of codes of practice, appropriate transport standards, industry quality assurance programmes and the enforcement of laws and regulations.
Space allowance during commercial long distance transport of cattle in North America.
González, L A; Schwartzkopf-Genswein, K S; Bryan, M; Silasi, R; Brown, F
2012-10-01
), compartment of the trailer (greater density in belly and deck), and number of axles on the vehicle (greater density with more axles). The present study provides a framework to assess and understand factors affecting SA during commercial long distance transport of cattle. This information is vital in assessing the consequences of changing industry standards, guidelines, recommended values, laws and regulations on animal welfare, the industry, and economics.
Criterion distances and environmental correlates of active commuting to school in children
2011-01-01
Background Active commuting to school can contribute to daily physical activity levels in children. Insight into the determinants of active commuting is needed, to promote such behavior in children living within a feasible commuting distance from school. This study determined feasible distances for walking and cycling to school (criterion distances) in 11- to 12-year-old Belgian children. For children living within these criterion distances from school, the correlation between parental perceptions of the environment, the number of motorized vehicles per family and the commuting mode (active/passive) to school was investigated. Methods Parents (n = 696) were contacted through 44 randomly selected classes of the final year (sixth grade) in elementary schools in East- and West-Flanders. Parental environmental perceptions were obtained using the parent version of Neighborhood Environment Walkability Scale for Youth (NEWS-Y). Information about active commuting to school was obtained using a self-reported questionnaire for parents. Distances from the children's home to school were objectively measured with Routenet online route planner. Criterion distances were set at the distance in which at least 85% of the active commuters lived. After the determination of these criterion distances, multilevel analyses were conducted to determine correlates of active commuting to school within these distances. Results Almost sixty percent (59.3%) of the total sample commuted actively to school. Criterion distances were set at 1.5 kilometers for walking and 3.0 kilometers for cycling. In the range of 2.01 - 2.50 kilometers household distance from school, the number of passive commuters exceeded the number of active commuters. For children who were living less than 3.0 kilometers away from school, only perceived accessibility by the parents was positively associated with active commuting to school. Within the group of active commuters, a longer distance to school was associated with
49 CFR 372.300 - Distances and population data.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 5 2012-10-01 2012-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...
49 CFR 372.300 - Distances and population data.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 5 2013-10-01 2013-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...
49 CFR 372.300 - Distances and population data.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 5 2010-10-01 2010-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...
49 CFR 372.300 - Distances and population data.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 5 2014-10-01 2014-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...
49 CFR 372.300 - Distances and population data.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 5 2011-10-01 2011-10-01 false Distances and population data. 372.300 Section 372..., COMMERCIAL ZONES, AND TERMINAL AREAS Terminal Areas § 372.300 Distances and population data. In the application of this subpart, distances and population data shall be determined in the same manner as provided...
Blegen, Nick
2017-02-01
This study presents the earliest evidence of long-distance obsidian transport at the ∼200 ka Sibilo School Road Site (SSRS), an early Middle Stone Age site in the Kapthurin Formation, Kenya. The later Middle Pleistocene of East Africa (130-400 ka) spans significant and interrelated behavioral and biological changes in human evolution including the first appearance of Homo sapiens. Despite the importance of the later Middle Pleistocene, there are relatively few archaeological sites in well-dated contexts (n < 10) that document hominin behavior from this time period. In particular, geochemically informed evidence of long-distance obsidian transport, important for investigating expansion of intergroup interactions in hominin evolution, is rare from the Middle Pleistocene record of Africa. The SSRS offers a unique contribution to this small but growing dataset. Tephrostratigraphic analysis of tuffs encasing the SSRS provides a minimum age of ∼200 ka for the site. Levallois points and methods of core preparation demonstrate characteristic Middle Stone Age lithic technologies present at the SSRS. A significant portion (43%) of the lithic assemblage is obsidian. The SSRS obsidian comes from three different sources located at distances of 25 km, 140 km and 166 km from the site. The majority of obsidian derives from the farthest source, 166 km to the south of the site. The SSRS thus provides important new evidence that long-distance raw material transport, and the expansion of hominin intergroup interactions that this entails, was a significant feature of hominin behavior ∼200 ka, the time of the first appearance of H. sapiens, and ∼150,000 years before similar behaviors were previously documented in the region. Copyright © 2016 Elsevier Ltd. All rights reserved.
Supin, Alexander Ya; Nachtigall, Paul E; Breese, Marlee
2010-06-01
Evidence of varying hearing sensitivity according to the target distance was obtained in a false killer whale Pseudorca crassidens during echolocation. Auditory evoked potentials (AEPs) triggered by echolocation clicks were recorded. The target distance varied from 1 to 6 m. The records contained AEPs to the self-heard emitted click and AEPs to the echoes. Mean level of echolocation clicks depended on distance (the longer the distance, the higher the click level), however, the effect of click level on AEP amplitude was eliminated by extracting AEPs to clicks of certain particular levels. The amplitude of the echo-provoked AEP was almost independent of distance, however, the amplitude of the AEP to the emitted click, did depend on distance within a range from 1 to 4 m: the longer the distance, the higher the amplitude. The latter result is interpreted as confirmational evidence that the animal is capable of varying hearing sensitivity according to target distance. The variation of hearing sensitivity may help to compensate for the echo attenuation with distance; as a secondary effect, this variation manifested itself in a variation of the amplitude of the AEP to emitted clicks.
ENDO, Yoshiro; TSUCHIYA, Takeru; OMURA, Takaya; NAKAI, Kenji; KOROSUE, Kenji; ISHIMARU, Mutsuki; ISHIKAWA, Yuhiro; HOBO, Seiji
2014-01-01
The present study evaluated the effects of single-dose marbofloxacin in protecting horses against fever associated with transportation using 48 healthy Thoroughbreds. All horses were premedicated with interferon-α (0.5 U/kg, sublingually, every 24 hr) for 2 days before transportation and on the day of transportation. Horses were randomly assigned to receive marbofloxacin (2 mg/kg, IV, once; MRFX group), enrofloxacin (5 mg/kg, IV, once; ERFX group) or saline (0.9% NaCl) solution (10 ml, IV, once; control group) ≤1 hr before being transportation. Each group contained 16 horses (8 males, 8 females). Horses were transported 1,210 km using commercial vans over the course of approximately 26 hr. Clinical examinations and hematologic analyses were performed on all horses both before and after transportation. Post-transportation neutrophil to lymphocyte ratios were significantly lower in horses in the MRFX group compared with the control horses. The serum amyloid A levels were significantly lower in horses in the MRFX group and ERFX group compared with the control horses. Regarding the post-transportation rectal temperatures, fever was detected in 0 horses and 1 horse in the MRFX and ERFX groups, respectively, whereas fevers exceeding 39.1°C were detected in 2 horses in the control group. Additionally, the number of essential post-transportation treatments provided by veterinarians was reduced 3-fold in the MRFX and ERFX groups compared with the saline group. MRFX provided ERFX-like protection against fever associated with long-distance transportation, yielding significantly better protection than saline. Administration of MRFX just before transportation deserves a further study for efficacy in preventing horse fever associated with transportation. PMID:25720808
Attachment style, self-concealment, and interpersonal distance among Japanese undergraduates.
Yukawa, Shintaro; Tokuda, Hideji; Sato, Jun
2007-06-01
The relationships among attachment style, self-concealment, and interpersonal distance were studied with 71 Japanese undergraduates (33 men and 38 women, ages 18 to 20 years, M = 18.7, SD= .6). Participants completed a questionnaire about Self-concealment and Attachment Styles (Secure, Anxious, and Avoidant). One week later, Interpersonal Distance, which individuals maintain between themselves and others, was measured by the stop-distance paradigm. Analysis showed that scores for more Anxious and Avoidant Attachment Styles were positively correlated with those for greater Self-concealment. Scores for greater Self-concealment and more Anxious Attachment Style were also correlated with longer Interpersonal Distance.
Walvoord, Michelle Ann; Andraski, Brian J.; Green, Christopher T.; Stonestrom, David A.; Striegl, Robert G.
2014-01-01
A natural gradient SF6 tracer experiment provided an unprecedented evaluation of long distance gas transport in the deep unsaturated zone (UZ) under controlled (known) conditions. The field-scale gas tracer test in the 110-m-thick UZ was conducted at the U.S. Geological Survey’s Amargosa Desert Research Site (ADRS) in southwestern Nevada. A history of anomalous (theoretically unexpected) contaminant gas transport observed at the ADRS, next to the first commercial low-level radioactive waste disposal facility in the United States, provided motivation for the SF6 tracer study. Tracer was injected into a deep UZ borehole at depths of 15 and 48 m, and plume migration was observed in a monitoring borehole 9 m away at various depths (0.5–109 m) over the course of 1 yr. Tracer results yielded useful information about gas transport as applicable to the spatial scales of interest for off-site contaminant transport in arid unsaturated zones. Modeling gas diffusion with standard empirical expressions reasonably explained SF6 plume migration, but tended to underpredict peak concentrations for the field-scale experiment given previously determined porosity information. Despite some discrepancies between observations and model results, rapid SF6 gas transport commensurate with previous contaminant migration was not observed. The results provide ancillary support for the concept that apparent anomalies in historic transport behavior at the ADRS are the result of factors other than nonreactive gas transport properties or processes currently in effect in the undisturbed UZ.
Schudt, Gordian; Kolesnikova, Larissa; Dolnik, Olga; Sodeik, Beate; Becker, Stephan
2013-01-01
Transport of large viral nucleocapsids from replication centers to assembly sites requires contributions from the host cytoskeleton via cellular adaptor and motor proteins. For the Marburg and Ebola viruses, related viruses that cause severe hemorrhagic fevers, the mechanism of nucleocapsid transport remains poorly understood. Here we developed and used live-cell imaging of fluorescently labeled viral and host proteins to characterize the dynamics and molecular requirements of nucleocapsid transport in Marburg virus-infected cells under biosafety level 4 conditions. The study showed a complex actin-based transport of nucleocapsids over long distances from the viral replication centers to the budding sites. Only after the nucleocapsids had associated with the matrix viral protein VP40 at the plasma membrane were they recruited into filopodia and cotransported with host motor myosin 10 toward the budding sites at the tip or side of the long cellular protrusions. Three different transport modes and velocities were identified: (i) Along actin filaments in the cytosol, nucleocapsids were transported at ∼200 nm/s; (ii) nucleocapsids migrated from one actin filament to another at ∼400 nm/s; and (iii) VP40-associated nucleocapsids moved inside filopodia at 100 nm/s. Unique insights into the spatiotemporal dynamics of nucleocapsids and their interaction with the cytoskeleton and motor proteins can lead to novel classes of antivirals that interfere with the trafficking and subsequent release of the Marburg virus from infected cells. PMID:23940347
Schudt, Gordian; Kolesnikova, Larissa; Dolnik, Olga; Sodeik, Beate; Becker, Stephan
2013-08-27
Transport of large viral nucleocapsids from replication centers to assembly sites requires contributions from the host cytoskeleton via cellular adaptor and motor proteins. For the Marburg and Ebola viruses, related viruses that cause severe hemorrhagic fevers, the mechanism of nucleocapsid transport remains poorly understood. Here we developed and used live-cell imaging of fluorescently labeled viral and host proteins to characterize the dynamics and molecular requirements of nucleocapsid transport in Marburg virus-infected cells under biosafety level 4 conditions. The study showed a complex actin-based transport of nucleocapsids over long distances from the viral replication centers to the budding sites. Only after the nucleocapsids had associated with the matrix viral protein VP40 at the plasma membrane were they recruited into filopodia and cotransported with host motor myosin 10 toward the budding sites at the tip or side of the long cellular protrusions. Three different transport modes and velocities were identified: (i) Along actin filaments in the cytosol, nucleocapsids were transported at ∼200 nm/s; (ii) nucleocapsids migrated from one actin filament to another at ∼400 nm/s; and (iii) VP40-associated nucleocapsids moved inside filopodia at 100 nm/s. Unique insights into the spatiotemporal dynamics of nucleocapsids and their interaction with the cytoskeleton and motor proteins can lead to novel classes of antivirals that interfere with the trafficking and subsequent release of the Marburg virus from infected cells.
Dettmer, Jan; Ursache, Robertas; Campilho, Ana; Miyashima, Shunsuke; Belevich, Ilya; O'Regan, Seana; Mullendore, Daniel Leroy; Yadav, Shri Ram; Lanz, Christa; Beverina, Luca; Papagni, Antonio; Schneeberger, Korbinian; Weigel, Detlef; Stierhof, York-Dieter; Moritz, Thomas; Knoblauch, Michael; Jokitalo, Eija; Helariutta, Ykä
2014-07-10
Phloem, a plant tissue responsible for long-distance molecular transport, harbours specific junctions, sieve areas, between the conducting cells. To date, little is known about the molecular framework related to the biogenesis of these sieve areas. Here we identify mutations at the CHER1/AtCTL1 locus of Arabidopsis thaliana. The mutations cause several phenotypic abnormalities, including reduced pore density and altered pore structure in the sieve areas associated with impaired phloem function. CHER1 encodes a member of a poorly characterized choline transporter-like protein family in plants and animals. We show that CHER1 facilitates choline transport, localizes to the trans-Golgi network, and during cytokinesis is associated with the phragmoplast. Consistent with its function in the elaboration of the sieve areas, CHER1 has a sustained, polar localization in the forming sieve plates. Our results indicate that the regulation of choline levels is crucial for phloem development and conductivity in plants.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Merrild, Hanna; Larsen, Anna W., E-mail: awla@env.dtu.dk; Christensen, Thomas H.
Highlights: Black-Right-Pointing-Pointer We model the environmental impact of recycling and incineration of household waste. Black-Right-Pointing-Pointer Recycling of paper, glass, steel and aluminium is better than incineration. Black-Right-Pointing-Pointer Recycling and incineration of cardboard and plastic can be equally good alternatives. Black-Right-Pointing-Pointer Recyclables can be transported long distances and still have environmental benefits. Black-Right-Pointing-Pointer Paper has a higher environmental benefit than recyclables found in smaller amounts. - Abstract: Recycling of materials from municipal solid waste is commonly considered to be superior to any other waste treatment alternative. For the material fractions with a significant energy content this might not be the casemore » if the treatment alternative is a waste-to-energy plant with high energy recovery rates. The environmental impacts from recycling and from incineration of six material fractions in household waste have been compared through life cycle assessment assuming high-performance technologies for material recycling as well as for waste incineration. The results showed that there are environmental benefits when recycling paper, glass, steel and aluminium instead of incinerating it. For cardboard and plastic the results were more unclear, depending on the level of energy recovery at the incineration plant, the system boundaries chosen and which impact category was in focus. Further, the environmental impact potentials from collection, pre-treatment and transport was compared to the environmental benefit from recycling and this showed that with the right means of transport, recyclables can in most cases be transported long distances. However, the results also showed that recycling of some of the material fractions can only contribute marginally in improving the overall waste management system taking into consideration their limited content in average Danish household waste.« less
The Roles for Prior Visual Experience and Age on the Extraction of Egocentric Distance.
Wallin, Courtney P; Gajewski, Daniel A; Teplitz, Rebeca W; Mihelic Jaidzeka, Sandra; Philbeck, John W
2017-01-01
In a well-lit room, observers can generate well-constrained estimates of the distance to an object on the floor even with just a fleeting glimpse. Performance under these conditions is typically characterized by some underestimation but improves when observers have previewed the room. Such evidence suggests that information extracted from longer durations may be stored to contribute to the perception of distance at limited time frames. Here, we examined the possibility that this stored information is used differentially across age. Specifically, we posited that older adults would rely more than younger adults on information gathered and stored at longer glimpses to judge the distance of briefly glimpsed objects. We collected distance judgments from younger and older adults after brief target glimpses. Half of the participants were provided 20-s previews of the testing room in advance; the other half received no preview. Performance benefits were observed for all individuals with prior visual experience, and these were moderately more pronounced for the older adults. The results suggest that observers store contextual information gained from longer viewing durations to aid in the perception of distance at brief glimpses, and that this memory becomes more important with age. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Schmale, David; Ross, Shane; Lin, Binbin
2014-05-01
Spores of fungi in the genus Fusarium may be transported through the atmosphere over long distances. Members of this genus are important pathogens and mycotoxin producers. New information is needed to characterize seasonal trends in atmospheric loads of Fusarium and to pinpoint the source(s) of inoculum at both local (farm) and regional (state or country) scales. Spores of Fusarium were collected from the atmosphere in an agricultural ecosystem in Blacksburg, VA, USA using a Burkard volumetric sampler (BVS) 1 m above ground level and autonomous unmanned aerial vehicles (UAVs) 100 m above ground level. More than 2,200 colony forming units (CFUs) of Fusarium were collected during 104 BVS sampling periods and 180 UAV sampling periods over four calendar years (2009-2012). Spore concentrations ranged from 0 to 13 and 0 to 23 spores m-3 for the BVS and the UAVs, respectively. Spore concentrations were generally higher in the fall, spring, and summer, and lower in the winter. Spore concentrations from the BVS were generally higher than those from the UAVs for both seasonal and hourly collections. Some of the species of Fusarium identified from our collections have not been previously reported in the state of Virginia. A Gaussian plume transport model was used to estimate distances to the potential inoculum source(s) by season. This work extends previous studies showing an association between atmospheric transport barriers (Lagrangian coherent structures or LCSs) and the movement of Fusarium in the lower atmosphere. An increased understanding of the aerobiology of Fusarium may contribute to new and improved control strategies for diseases causes by fusaria in the future.
Klose, T; Borchert, H-H; Pruss, A; Roth, W-K; Bohnen, H R; Putzker, M
2010-07-01
The German Armed Forces Blood Service in Koblenz supplies red blood cell concentrates (RBCs) to military and civilian institutions at home and to field hospitals during peacekeeping operations abroad. During long-distance transport, blood products can be exposed to extreme environmental conditions or inappropriate handling, which may compromise product quality. Different active and passive cooling systems, cooling elements, packaging material and data loggers were examined in a climate chamber. A number of techniques for measuring temperature were investigated in order to preserve the blood products' quality during transport, including some field tests with multiparametric data recording. Any kind of active cooling systems, conventional cooling elements and customary packaging material, as well as temperature-sensitive labels, minimum-maximum thermometers and intra-product measurement were found to be unsuitable for military requirement. The best results were obtained when the passively cooling RCB 25 transport box (Dometic) was used together with latent heat/cold storage elements (deltaT) and Junior data loggers (Escort). The elaborated protocol allows temperatures to be maintained between 2 and 6 degrees C as required by European guidelines for at least 36 h each and between 1 and 10 degrees C as required by German guidelines for at least 48 or 64 h at ambient temperatures between -10 and 40 degrees C. Preliminary results indicate that care must be taken concerning additional factors such as air pressure variation or vibration.
Smartphone viewing distance and sleep: an experimental study utilizing motion capture technology
Yoshimura, Michitaka; Kitazawa, Momoko; Maeda, Yasuhiro; Mimura, Masaru; Tsubota, Kazuo; Kishimoto, Taishiro
2017-01-01
There are studies reporting the negative impact of smartphone utilization on sleep. It is considered that reduction of melatonin secretion under the blue light exposure from smart-phone displays is one of the causes. The viewing distance may cause sleep disturbance, because the viewing distance determines the screen illuminance and/or asthenopia. However, to date, there has been no study closely investigating the impact of viewing distance on sleep; therefore, we sought to determine the relationship between smartphone viewing distance and subjective sleep status. Twenty-three nursing students (mean age ± standard deviation of 19.7±3.1 years) participated in the study. Subjective sleep status was assessed using the Pittsburgh Sleep Quality Index, morningness–eveningness questionnaire, and the Epworth sleepiness scale. We used the distance between the head and the hand while holding a smartphone to measure the viewing distance while using smartphones in sitting and lying positions. The distance was calculated using the three-dimensional coordinates obtained by a noncontact motion-sensing device. The viewing distance of smartphones in the sitting position ranged from 13.3 to 32.9 cm among participants. In the lying position, it ranged from 9.9 to 21.3cm. The viewing distance was longer in the sitting position than in the lying position (mean ± standard deviation: 20.3±4.7 vs 16.4±2.7, respectively, P<0.01). We found that the short viewing distance in the lying position had a positive correlation to a poorer sleep state (R2=0.27, P<0.05), lower sleep efficiency (R2=0.35, P<0.05), and longer sleep latency (R2=0.38, P<0.05). Moreover, smartphone viewing distances in lying position correlated negatively with subjective sleep status. Therefore, when recommending ideal smartphone use in lying position, one should take into account the viewing distances. PMID:28331379
Smartphone viewing distance and sleep: an experimental study utilizing motion capture technology.
Yoshimura, Michitaka; Kitazawa, Momoko; Maeda, Yasuhiro; Mimura, Masaru; Tsubota, Kazuo; Kishimoto, Taishiro
2017-01-01
There are studies reporting the negative impact of smartphone utilization on sleep. It is considered that reduction of melatonin secretion under the blue light exposure from smart-phone displays is one of the causes. The viewing distance may cause sleep disturbance, because the viewing distance determines the screen illuminance and/or asthenopia. However, to date, there has been no study closely investigating the impact of viewing distance on sleep; therefore, we sought to determine the relationship between smartphone viewing distance and subjective sleep status. Twenty-three nursing students (mean age ± standard deviation of 19.7±3.1 years) participated in the study. Subjective sleep status was assessed using the Pittsburgh Sleep Quality Index, morningness-eveningness questionnaire, and the Epworth sleepiness scale. We used the distance between the head and the hand while holding a smartphone to measure the viewing distance while using smartphones in sitting and lying positions. The distance was calculated using the three-dimensional coordinates obtained by a noncontact motion-sensing device. The viewing distance of smartphones in the sitting position ranged from 13.3 to 32.9 cm among participants. In the lying position, it ranged from 9.9 to 21.3cm. The viewing distance was longer in the sitting position than in the lying position (mean ± standard deviation: 20.3±4.7 vs 16.4±2.7, respectively, P <0.01). We found that the short viewing distance in the lying position had a positive correlation to a poorer sleep state ( R 2 =0.27, P <0.05), lower sleep efficiency ( R 2 =0.35, P <0.05), and longer sleep latency ( R 2 =0.38, P <0.05). Moreover, smartphone viewing distances in lying position correlated negatively with subjective sleep status. Therefore, when recommending ideal smartphone use in lying position, one should take into account the viewing distances.
14 CFR 420.70 - Separation distance measurement requirements.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Separation distance measurement requirements. 420.70 Section 420.70 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION... energetic liquids or net explosive weight that requires the greater distance. [Docket No. FAA-2011-0105, 77...
14 CFR 420.70 - Separation distance measurement requirements.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Separation distance measurement requirements. 420.70 Section 420.70 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION... energetic liquids or net explosive weight that requires the greater distance. [Docket No. FAA-2011-0105, 77...
Holmes, Jordan A; Carpenter, William R; Wu, Yang; Hendrix, Laura H; Peacock, Sharon; Massing, Mark; Schenck, Anna P; Meyer, Anne-Marie; Diao, Kevin; Wheeler, Stephanie B; Godley, Paul A; Stitzenberg, Karyn B; Chen, Ronald C
2012-03-01
We examined whether an increased distance to a urologist is associated with a delayed diagnosis of prostate cancer among black and white patients, as manifested by higher risk disease at diagnosis. North Carolina Central Cancer Registry data were linked to Medicare claims for patients with incident prostate cancer diagnosed in 2004 to 2005. Straight-line distances were calculated from the patient home to the nearest urologist. Race stratified multivariate ordinal logistic regression was used to examine the association between distance to a urologist and prostate cancer risk group (low, intermediate, high or very high/metastasis) at diagnosis for black and white patients while accounting for age, comorbidity, marital status and diagnosis year. An overall model was then used to examine the distance × race interaction effect. Included in analysis were 1,720 white and 531 black men. In the overall cohort the high risk cancer rate increased monotonically with distance to a urologist, including 40% for 0 to 10, 45% for 11 to 20 and 57% for greater than 20 miles. Correspondingly the low risk cancer rate decreased with longer distance. On race stratified multivariate analysis longer distance was associated with higher risk prostate cancer for white and black patients (p = 0.04 and <0.01, respectively) but the effect was larger in the latter group. The distance × race interaction term was significant in the overall model (p = 0.03). Longer distance to a urologist may disproportionally impact black patients. Decreasing modifiable barriers to health care access, such as distance to care, may decrease racial disparities in prostate cancer. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Estimation of septic tank setback distances based on transport of E. coli and F-RNA phages.
Pang, Liping; Close, Murray; Goltz, Mark; Sinton, Lester; Davies, Helen; Hall, Carollyn; Stanton, Greg
2004-01-01
Setback distances between septic tank systems and the shorelines of Lake Okareka, New Zealand were determined from model simulations for a worst-case scenario, using the highest hydraulic conductivity and gradient measured in the field, removal rates of the microbial indicators (Escherichia coli and F-RNA phages) determined from a column experiment, and maximum values of the design criteria for the disposal system, and assuming an absence of an unsaturated zone, a continuous discharge of the raw effluent from a failed or non-complying treatment system (both indicators at concentrations of 1x10(7) counts/100 ml) into the groundwater and no sorption of pathogens in the aquifer. Modelling results suggest that the minimal setback distances were 16 m to satisfy the New Zealand Recreational Water Quality Guidelines for E. coli <126 per 100 ml (Ministry for the Environment, 1999) and 48 m to meet the Drinking-Water Standards for New Zealand 2000 for enteric virus <1 per 100 l (Ministry of Health, 2000). These distances may be applicable for other lakeshores in pumice sand aquifers with groundwater velocities <7 m/day. Findings of laboratory column and batch experiments provided an insight into the microbial attenuation and transport processes in pumice sand aquifers. Bacterial removal was predominately through filtration (87-88%) and partially by die-off (12-13%), while viral removal was by both die-off (45%) and filtration (55%). In addition, microbial die-off in groundwater without aquifer material (i.e., free microbes) was much lower than die-off in groundwater with aquifer material (i.e., sorbed microbes) and contributed only 2-6% to the total removal. This implies that the setback distances estimated from die-off rates for the free microbes, determined in the laboratory without considering aquifer media and other removal processes, which are often reported in the literature, could be larger than necessary.
Shape Classification Using Wasserstein Distance for Brain Morphometry Analysis.
Su, Zhengyu; Zeng, Wei; Wang, Yalin; Lu, Zhong-Lin; Gu, Xianfeng
2015-01-01
Brain morphometry study plays a fundamental role in medical imaging analysis and diagnosis. This work proposes a novel framework for brain cortical surface classification using Wasserstein distance, based on uniformization theory and Riemannian optimal mass transport theory. By Poincare uniformization theorem, all shapes can be conformally deformed to one of the three canonical spaces: the unit sphere, the Euclidean plane or the hyperbolic plane. The uniformization map will distort the surface area elements. The area-distortion factor gives a probability measure on the canonical uniformization space. All the probability measures on a Riemannian manifold form the Wasserstein space. Given any 2 probability measures, there is a unique optimal mass transport map between them, the transportation cost defines the Wasserstein distance between them. Wasserstein distance gives a Riemannian metric for the Wasserstein space. It intrinsically measures the dissimilarities between shapes and thus has the potential for shape classification. To the best of our knowledge, this is the first. work to introduce the optimal mass transport map to general Riemannian manifolds. The method is based on geodesic power Voronoi diagram. Comparing to the conventional methods, our approach solely depends on Riemannian metrics and is invariant under rigid motions and scalings, thus it intrinsically measures shape distance. Experimental results on classifying brain cortical surfaces with different intelligence quotients demonstrated the efficiency and efficacy of our method.
Shape Classification Using Wasserstein Distance for Brain Morphometry Analysis
Su, Zhengyu; Zeng, Wei; Wang, Yalin; Lu, Zhong-Lin; Gu, Xianfeng
2015-01-01
Brain morphometry study plays a fundamental role in medical imaging analysis and diagnosis. This work proposes a novel framework for brain cortical surface classification using Wasserstein distance, based on uniformization theory and Riemannian optimal mass transport theory. By Poincare uniformization theorem, all shapes can be conformally deformed to one of the three canonical spaces: the unit sphere, the Euclidean plane or the hyperbolic plane. The uniformization map will distort the surface area elements. The area-distortion factor gives a probability measure on the canonical uniformization space. All the probability measures on a Riemannian manifold form the Wasserstein space. Given any 2 probability measures, there is a unique optimal mass transport map between them, the transportation cost defines the Wasserstein distance between them. Wasserstein distance gives a Riemannian metric for the Wasserstein space. It intrinsically measures the dissimilarities between shapes and thus has the potential for shape classification. To the best of our knowledge, this is the first work to introduce the optimal mass transport map to general Riemannian manifolds. The method is based on geodesic power Voronoi diagram. Comparing to the conventional methods, our approach solely depends on Riemannian metrics and is invariant under rigid motions and scalings, thus it intrinsically measures shape distance. Experimental results on classifying brain cortical surfaces with different intelligence quotients demonstrated the efficiency and efficacy of our method. PMID:26221691
Perceived distance depends on the orientation of both the body and the visual environment.
Harris, Laurence R; Mander, Charles
2014-10-15
Models of depth perception typically omit the orientation and height of the observer despite the potential usefulness of the height above the ground plane and the need to know about head position to interpret retinal disparity information. To assess the contribution of orientation to perceived distance, we used the York University Tumbled and Tumbling Room facilities to modulate both perceived and actual body orientation. These facilities are realistically decorated rooms that can be systematically arranged to vary the relative orientation of visual, gravity, and body cues to upright. To assess perceived depth we exploited size/distance constancy. Observers judged the perceived length of a visual line (controlled by a QUEST adaptive procedure) projected on to the wall of the facilities, relative to the length of an unseen iron rod held in their hands. In the Tumbled Room (viewing distance 337 cm) the line was set about 10% longer when participants were supine compared to when they were upright. In the Tumbling Room (viewing distance 114 cm), the line was set about 11% longer when participants were either supine or made to feel that they were supine by the orientation of the room. Matching a longer visual line to the reference rod is compatible with the opposite wall being perceived as closer. The effect was modulated by whether viewing was monocular or binocular at a viewing distance of 114 cm but not at 337 cm suggesting that reliable binocular cues can override the effect. © 2014 ARVO.
Hunt, Kathleen E; Innis, Charles J; Kennedy, Adam E; McNally, Kerry L; Davis, Deborah G; Burgess, Elizabeth A; Merigo, Constance
2016-01-01
Sea turtle rehabilitation centres frequently transport sea turtles for long distances to move animals between centres or to release them at beaches, yet there is little information on the possible effects of transportation-related stress ('transport stress') on sea turtles. To assess whether transport stress is a clinically relevant concern for endangered Kemp's ridley sea turtles (Lepidochelys kempii), we obtained pre-transport and post-transport plasma samples from 26 juvenile Kemp's ridley sea turtles that were transported for 13 h (n = 15 turtles) or 26 h (n = 11 turtles) by truck for release at beaches. To control for effects of handling, food restriction and time of day, the same turtles were also studied on 'control days' 2 weeks prior to transport, i.e. with two samples taken to mimic pre-transport and post-transport timing, but without transportation. Blood samples were analysed for nine clinical health measures (pH, pCO2, pO2, HCO3, sodium, potassium, ionized calcium, lactate and haematocrit) and four 'stress-associated' parameters (corticosterone, glucose, white blood cell count and heterophil-to-lymphocyte ratio). Vital signs (heart rate, respiratory rate and cloacal temperature) were also monitored. Corticosterone and glucose showed pronounced elevations due specifically to transportation; for corticosterone, this elevation was significant only for the longer transport duration, whereas glucose increased significantly after both transport durations. However, clinical health measures and vital signs showed minimal or no changes in response to any sampling event (with or without transport), and all turtles appeared to be in good clinical health after both transport durations. Thus, transportation elicits a mild, but detectable, adrenal stress response that is more pronounced during longer durations of transport; nonetheless, Kemp's ridley sea turtles can tolerate ground transportation of up to 26 h in good health. These results are likely
Bernardi Aubry, Fabrizio; Falcieri, Francesco Marcello; Chiggiato, Jacopo; Boldrin, Alfredo; Luna, Gian Marco; Finotto, Stefania; Camatti, Elisa; Acri, Francesco; Sclavo, Mauro; Carniel, Sandro; Bongiorni, Lucia
2018-03-14
Dense waters (DW) formation in shelf areas and their cascading off the shelf break play a major role in ventilating deep waters, thus potentially affecting ecosystem functioning and biogeochemical cycles. However, whether DW flow across shelves may affect the composition and structure of plankton communities down to the seafloor and the particles transport over long distances has not been fully investigated. Following the 2012 north Adriatic Sea cold outbreak, DW masses were intercepted at ca. 460 km south the area of origin and compared to resident ones in term of plankton biomass partitioning (pico to micro size) and phytoplankton species composition. Results indicated a relatively higher contribution of heterotrophs in DW than in deep resident water masses, probably as result of DW-mediated advection of fresh organic matter available to consumers. DWs showed unusual high abundances of Skeletonema sp., a diatom that bloomed in the north Adriatic during DW formation. The Lagrangian numerical model set up on this diatom confirmed that DW flow could be an important mechanism for plankton/particles export to deep waters. We conclude that the predicted climate-induced variability in DW formation events could have the potential to affect the ecosystem functioning of the deeper part of the Mediterranean basin, even at significant distance from generation sites.
14 CFR 29.81 - Landing distance: Category A.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Landing distance: Category A. 29.81 Section... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.81 Landing distance: Category A... knots for water landings) from a point 50 ft above the landing surface must be determined from the...
14 CFR 29.81 - Landing distance: Category A.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Landing distance: Category A. 29.81 Section... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.81 Landing distance: Category A... knots for water landings) from a point 50 ft above the landing surface must be determined from the...
Memoryless self-reinforcing directionality in endosomal active transport within living cells
NASA Astrophysics Data System (ADS)
Chen, Kejia; Wang, Bo; Granick, Steve
2015-06-01
In contrast to Brownian transport, the active motility of microbes, cells, animals and even humans often follows another random process known as truncated Lévy walk. These stochastic motions are characterized by clustered small steps and intermittent longer jumps that often extend towards the size of the entire system. As there are repeated suggestions, although disagreement, that Lévy walks have functional advantages over Brownian motion in random searching and transport kinetics, their intentional engineering into active materials could be useful. Here, we show experimentally in the classic active matter system of intracellular trafficking that Brownian-like steps self-organize into truncated Lévy walks through an apparent time-independent positive feedback such that directional persistence increases with the distance travelled persistently. A molecular model that allows the maximum output of the active propelling forces to fluctuate slowly fits the experiments quantitatively. Our findings offer design principles for programming efficient transport in active materials.
The ideal subject distance for passport pictures.
Verhoff, Marcel A; Witzel, Carsten; Kreutz, Kerstin; Ramsthaler, Frank
2008-07-04
In an age of global combat against terrorism, the recognition and identification of people on document images is of increasing significance. Experiments and calculations have shown that the camera-to-subject distance - not the focal length of the lens - can have a significant effect on facial proportions. Modern passport pictures should be able to function as a reference image for automatic and manual picture comparisons. This requires a defined subject distance. It is completely unclear which subject distance, in the taking of passport photographs, is ideal for the recognition of the actual person. We show here that the camera-to-subject distance that is perceived as ideal is dependent on the face being photographed, even if the distance of 2m was most frequently preferred. So far the problem of the ideal camera-to-subject distance for faces has only been approached through technical calculations. We have, for the first time, answered this question experimentally with a double-blind experiment. Even if there is apparently no ideal camera-to-subject distance valid for every face, 2m can be proposed as ideal for the taking of passport pictures. The first step would actually be the determination of a camera-to-subject distance for the taking of passport pictures within the standards. From an anthropological point of view it would be interesting to find out which facial features allow the preference of a shorter camera-to-subject distance and which allow the preference of a longer camera-to-subject distance.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 2 2014-10-01 2014-10-01 false Separation distances for undeveloped film from... Classification of Material § 175.706 Separation distances for undeveloped film from packages containing Class 7... film. Transport index Minimum separation distance to nearest undeveloped film for various times in...
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 2 2011-10-01 2011-10-01 false Separation distances for undeveloped film from... Classification of Material § 175.706 Separation distances for undeveloped film from packages containing Class 7... film. Transport index Minimum separation distance to nearest undeveloped film for various times in...
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 2 2013-10-01 2013-10-01 false Separation distances for undeveloped film from... Classification of Material § 175.706 Separation distances for undeveloped film from packages containing Class 7... film. Transport index Minimum separation distance to nearest undeveloped film for various times in...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 2 2012-10-01 2012-10-01 false Separation distances for undeveloped film from... Classification of Material § 175.706 Separation distances for undeveloped film from packages containing Class 7... film. Transport index Minimum separation distance to nearest undeveloped film for various times in...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 2 2010-10-01 2010-10-01 false Separation distances for undeveloped film from... Classification of Material § 175.706 Separation distances for undeveloped film from packages containing Class 7... film. Transport index Minimum separation distance to nearest undeveloped film for various times in...
Hunt, Kathleen E.; Innis, Charles J.; Kennedy, Adam E.; McNally, Kerry L.; Davis, Deborah G.; Burgess, Elizabeth A.; Merigo, Constance
2016-01-01
Sea turtle rehabilitation centres frequently transport sea turtles for long distances to move animals between centres or to release them at beaches, yet there is little information on the possible effects of transportation-related stress (‘transport stress’) on sea turtles. To assess whether transport stress is a clinically relevant concern for endangered Kemp’s ridley sea turtles (Lepidochelys kempii), we obtained pre-transport and post-transport plasma samples from 26 juvenile Kemp’s ridley sea turtles that were transported for 13 h (n = 15 turtles) or 26 h (n = 11 turtles) by truck for release at beaches. To control for effects of handling, food restriction and time of day, the same turtles were also studied on ‘control days’ 2 weeks prior to transport, i.e. with two samples taken to mimic pre-transport and post-transport timing, but without transportation. Blood samples were analysed for nine clinical health measures (pH, pCO2, pO2, HCO3, sodium, potassium, ionized calcium, lactate and haematocrit) and four ‘stress-associated’ parameters (corticosterone, glucose, white blood cell count and heterophil-to-lymphocyte ratio). Vital signs (heart rate, respiratory rate and cloacal temperature) were also monitored. Corticosterone and glucose showed pronounced elevations due specifically to transportation; for corticosterone, this elevation was significant only for the longer transport duration, whereas glucose increased significantly after both transport durations. However, clinical health measures and vital signs showed minimal or no changes in response to any sampling event (with or without transport), and all turtles appeared to be in good clinical health after both transport durations. Thus, transportation elicits a mild, but detectable, adrenal stress response that is more pronounced during longer durations of transport; nonetheless, Kemp’s ridley sea turtles can tolerate ground transportation of up to 26 h in good health. These
Mechanical analysis of the roundhouse kick according to height and distance in taekwondo.
Estevan, I; Falco, C
2013-12-01
Competition regulation in taekwondo has experienced several changes during the last few years, for example, kicks to the head score more points than kicks to the chest. In addition, some external factors such as the height of target and execution distance seem to affect the kick performance. The aim of this study was to analyse selected biomechanical parameters (impact force, reaction time, and execution time) according to the height and execution distance in two different male groups (experts (n = 12) and novices (n = 21)). Athletes kicked twice from every execution distance (short, normal and long) and towards two different heights of target (chest and head) in a random order. Novices kicked to the head with a longer reaction time than to the chest (p < 0.05) but experts were able to kick with similar performance for both heights. From short and normal distances experts kicked with similar performance; whereas from the normal distance novices had longer reaction and execution time than from the short distance (p < 0.05). In conclusion, in counterattacking situations, experts should perform the roundhouse kick to the head instead of to the chest, because it produces better scores with similar performance; whereas novice athletes should avoid kicking to the head because they are not able to kick with similar performance. Moreover, it is recommended that during counterattacks higher-level taekwondo athletes should intend to kick from normal distances.
MECHANICAL ANALYSIS OF THE ROUNDHOUSE KICK ACCORDING TO HEIGHT AND DISTANCE IN TAEKWONDO
Falco, C.
2013-01-01
Competition regulation in taekwondo has experienced several changes during the last few years, for example, kicks to the head score more points than kicks to the chest. In addition, some external factors such as the height of target and execution distance seem to affect the kick performance. The aim of this study was to analyse selected biomechanical parameters (impact force, reaction time, and execution time) according to the height and execution distance in two different male groups (experts (n = 12) and novices (n = 21)). Athletes kicked twice from every execution distance (short, normal and long) and towards two different heights of target (chest and head) in a random order. Novices kicked to the head with a longer reaction time than to the chest (p < 0.05) but experts were able to kick with similar performance for both heights. From short and normal distances experts kicked with similar performance; whereas from the normal distance novices had longer reaction and execution time than from the short distance (p < 0.05). In conclusion, in counterattacking situations, experts should perform the roundhouse kick to the head instead of to the chest, because it produces better scores with similar performance; whereas novice athletes should avoid kicking to the head because they are not able to kick with similar performance. Moreover, it is recommended that during counterattacks higher-level taekwondo athletes should intend to kick from normal distances. PMID:24744499
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-09
... DEPARTMENT OF TRANSPORTATION Federal Motor Carrier Safety Administration [Docket No. FMCSA-2010-0273] Notice of Request for Information (RFI): Training Certification for Drivers of Longer Combination Vehicles AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Notice; request for...
DOT National Transportation Integrated Search
2015-01-01
Policies that encourage reduced travel, such as traveling shorter distances, and increased use of more efficient transportation modes, such as public transportation and high-occupancy private automobiles, are often considered one of several possible ...
Williamson, Ann; Friswell, Rena
2013-09-01
The aim of this study was to explore the effects of external influences on long distance trucking, in particular, incentive-based remuneration systems and the need to wait or queue to load or unload on driver experiences of fatigue. Long distance truck drivers (n=475) were recruited at truck rest stops on the major transport corridors within New South Wales, Australia and asked to complete a survey by self-administration or interview. The survey covered demographics, usual working arrangements, details of the last trip and safety outcomes including fatigue experiences. On average drivers' last trip was over 2000 km and took 21.5 h to complete with an additional 6h of non-driving work. Incentive payments were associated with longer working hours, greater distances driven and higher fatigue for more drivers. Drivers required to wait in queues did significantly more non-driving work and experienced fatigue more often than those who did not. Drivers who were not paid to wait did the longest trips with average weekly hours above the legal working hours limits, had the highest levels of fatigue and the highest levels of interference by work with family life. In contrast, drivers who were paid to wait did significantly less work with shorter usual hours and shorter last trips. Multivariate analysis showed that incentive-based payment and unpaid waiting in queues were significant predictors of driver fatigue. The findings suggest that mandating payment of drivers for non-driving work including waiting would reduce the amount of non-driving work required for drivers and reduce weekly hours of work. In turn this would reduce driver fatigue and safety risk as well as enhancing the efficiency of the long distance road transport industry. Copyright © 2013 Elsevier Ltd. All rights reserved.
Perception of Egocentric Distance during Gravitational Changes in Parabolic Flight.
Clément, Gilles; Loureiro, Nuno; Sousa, Duarte; Zandvliet, Andre
2016-01-01
We explored the effect of gravity on the perceived representation of the absolute distance of objects to the observers within the range from 1.5-6 m. Experiments were performed on board the CNES Airbus Zero-G during parabolic flights eliciting repeated exposures to short periods of microgravity (0 g), hypergravity (1.8 g), and normal gravity (1 g). Two methods for obtaining estimates of perceived egocentric distance were used: verbal reports and visually directed motion toward a memorized visual target. For the latter method, because normal walking is not possible in 0 g, blindfolded subjects translated toward the visual target by pulling on a rope with their arms. The results showed that distance estimates using both verbal reports and blind pulling were significantly different between normal gravity, microgravity, and hypergravity. Compared to the 1 g measurements, the estimates of perceived distance using blind pulling were shorter for all distances in 1.8 g, whereas in 0 g they were longer for distances up to 4 m and shorter for distances beyond. These findings suggest that gravity plays a role in both the sensorimotor system and the perceptual/cognitive system for estimating egocentric distance.
Perception of Egocentric Distance during Gravitational Changes in Parabolic Flight
Clément, Gilles; Loureiro, Nuno; Sousa, Duarte; Zandvliet, Andre
2016-01-01
We explored the effect of gravity on the perceived representation of the absolute distance of objects to the observers within the range from 1.5–6 m. Experiments were performed on board the CNES Airbus Zero-G during parabolic flights eliciting repeated exposures to short periods of microgravity (0 g), hypergravity (1.8 g), and normal gravity (1 g). Two methods for obtaining estimates of perceived egocentric distance were used: verbal reports and visually directed motion toward a memorized visual target. For the latter method, because normal walking is not possible in 0 g, blindfolded subjects translated toward the visual target by pulling on a rope with their arms. The results showed that distance estimates using both verbal reports and blind pulling were significantly different between normal gravity, microgravity, and hypergravity. Compared to the 1 g measurements, the estimates of perceived distance using blind pulling were shorter for all distances in 1.8 g, whereas in 0 g they were longer for distances up to 4 m and shorter for distances beyond. These findings suggest that gravity plays a role in both the sensorimotor system and the perceptual/cognitive system for estimating egocentric distance. PMID:27463106
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 5 2012-10-01 2012-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 5 2014-10-01 2014-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 5 2013-10-01 2013-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 5 2010-10-01 2010-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 5 2011-10-01 2011-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
NASA Astrophysics Data System (ADS)
Prussin, Aaron Justin, II
Fusarium head blight (FHB), caused by Fusarium graminearum , is a serious disease of wheat and barley that has caused several billion dollars in crop losses over the last decade in the United States. Spores of F. graminearum are released from corn and small grain residues left-over from the previous growing season and are transported long distances in the atmosphere before being deposited. Current risk assessment tools consider environmental conditions favorable for disease development, but do not include spore transport. Long distance transport models have been proposed for a number of plant pathogens, but many of these models have not been experimentally validated. In order to predict the atmospheric transport of F. graminearum, the potential source strength ( Qpot) of inoculum must be known. We conducted a series of laboratory and field experiments to estimate Qpot from a field-scale source of inoculum of F. graminearum. Perithecia were generated on artificial (carrot agar) and natural (corn stalk) substrates. Artificial substrate (carrot agar) produced 15+/-0.4 perithecia cm-2, and natural substrate (corn stalk) produced 44+/-2 perithecia cm-2. Individual perithecia were excised from both substrate types and allowed to release ascospores every 24 hours. Perithecia generated from artificial (carrot agar) and natural (corn stalk) substrates released a mean of 104+/-5 and 276+/-16 ascospores, respectively. A volumetric spore trap was placed inside a 3,716 m2 clonal source of inoculum in 2011 and 2012. Results indicated that ascospores were released under field conditions predominantly (>90%) during the night (1900 to 0700 hours). Estimates of Qpot for our field-scale sources of inoculum were approximately 4 billion ascospores per 3,716 m 2. Release-recapture studies were conducted from a clonal field-scale source of F. graminearum in 2011 and 2012. Microsatellites were used to identify the released clone of F. graminearum at distances up to 1 km from the source
A Technology Primer for Distance Educators.
ERIC Educational Resources Information Center
Wagner, Ellen D.
An introduction to instructional technology systems used for distance learning applications is provided, with a compilation of technical information in straightforward terms. Broadcast communications theory is discussed, and several models of communications are considered, including transport mechanics and network facilities. The most prevalent…
Why the bigger live longer and travel farther: animals, vehicles, rivers and the winds.
Bejan, Adrian
2012-01-01
Here we show that constructal-law physics unifies the design of animate and inanimate movement by requiring that larger bodies move farther, and their movement on the landscape last longer. The life span of mammals must scale as the body mass (M) raised to the power 1/4, and the distance traveled during the lifetime must increase with body size. The same size effect on life span and distance traveled holds for the other flows that move mass on earth: atmospheric and oceanic jets and plumes, river basins, animals and human operated vehicles. The physics is the same for all flow systems on the landscape: the scaling rules of "design" are expressions of the natural tendency of all flow systems to generate designs that facilitate flow access. This natural tendency is the constructal law of design and evolution in nature. Larger bodies are more efficient movers of mass on the landscape.
Transport of Escherichia coli in 25 m quartz sand columns
NASA Astrophysics Data System (ADS)
Lutterodt, G.; Foppen, J. W. A.; Maksoud, A.; Uhlenbrook, S.
2011-01-01
may possess the so-called minimum sticking efficiency, thus expressing their ability to be transported over distances longer than what might be predicted using measured sticking efficiencies from experiments with both short (< 1 m) and long columns (> 25 m). Also variable values of sticking efficiencies within and among the strains show heterogeneities possibly due to variations in cell surface characteristics of the strains. The low sticking efficiency values measured express the importance of the long columns used in the experiments and the lower values of extrapolated minimum sticking efficiencies makes the method a valuable tool in delineating protection areas in real-world scenarios.
The impact of precipitation on land interfacility transport times.
Giang, Wayne C W; Donmez, Birsen; Ahghari, Mahvareh; MacDonald, Russell D
2014-12-01
Timely transfer of patients among facilities within a regionalized critical-care system remains a large obstacle to effective patient care. For medical transport systems where dispatchers are responsible for planning these interfacility transfers, accurate estimates of interfacility transfer times play a large role in planning and resource-allocation decisions. However, the impact of adverse weather conditions on transfer times is not well understood. Precipitation negatively impacts driving conditions and can decrease free-flow speeds and increase travel times. The objective of this research was to quantify and model the effects of different precipitation types on land travel times for interfacility patient transfers. It was hypothesized that the effects of precipitation would accumulate as the distance of the transfer increased, and they would differ based on the type of precipitation. Urgent and emergent interfacility transfers carried out by the medical transport system in Ontario from 2005 through 2011 were linked to Environment Canada's (Gatineau, Quebec, Canada) climate data. Two linear models were built to estimate travel times based on precipitation type and driving distance: one for transfers between cities (intercity) and another for transfers within a city (intracity). Precipitation affected both transfer types. For intercity transfers, the magnitude of the delays increased as driving distance increased. For median-distance intercity transfers (48 km), snow produced delays of approximately 9.1% (3.1 minutes), while rain produced delays of 8.4% (2.9 minutes). For intracity transfers, the magnitude of delays attributed to precipitation did not depend on distance driven. Transfers in rain were 8.6% longer (1.7 minutes) compared to no precipitation, whereas only statistically marginal effects were observed for snow. Precipitation increases the duration of interfacility land ambulance travel times by eight percent to ten percent. For transfers between cities
NASA Astrophysics Data System (ADS)
Scheingross, J. S.; Hovius, N.; Sachse, D.; Vieth-Hillebrand, A.; Turowski, J. M.; Hilton, R. G.
2016-12-01
Over geologic timescales, the exchange of organic carbon (OC) between the atmosphere, rock, and biosphere is thought to be a major control on global climate. CO2 flux estimates from oxidation of rock-derived OC and sequestration of biospheric OC during fluvial transit from source to sink are approximately the same order of magnitude or larger than those from silicate weathering. Despite field data showing loss of OC moving downstream in lowland rivers, it is unclear if losses occur primarily during active fluvial transport within the river, where OC is in continual motion within an aerated environment, or during longer periods when OC is temporarily stored in river floodplains which may be anoxic. This represents a major knowledge gap, as the unknown location of OC oxidation (i.e., river vs. floodplain) limits our ability to develop process-based models that can be employed to predict OC losses, constrain carbon budgets, and unravel links between climate, tectonics, and erosion. To fill this gap, we investigated the potential for OC oxidation in laboratory experiments simulating fluvial transport without floodplain storage. Mixtures of OC-rich and siliciclastic sediment were transported for distances of 2000 km in annular flumes while making time-series measurements of sediment TOC and water DOC concentrations. Initial results for transport of OC-rich soil show increasing DOC with transport distance to levels that represent a transfer of 2% of the total OC from the solid to the dissolved phase; however, we observed no detectable change in the solid-phase TOC. Similar results were obtained in a control experiment with identical sediment in still water. These preliminary results suggest minimal OC oxidation within our experiment, and, to the extent that such experiments represent natural transport through river systems, are consistent with the hypothesis that OC losses may occur primarily during floodplain storage rather than fluvial transport.
49 CFR 176.708 - Segregation distances.
Code of Federal Regulations, 2013 CFR
2013-10-01
... distances between radioactive materials and spaces regularly occupied by crew members or passengers, or... or YELLOW-III packages or overpacks must not be transported in spaces occupied by passengers, except... regularly occupied spaces or living quarters; or (2) For one or more consignments of Class 7 (radioactive...
49 CFR 176.708 - Segregation distances.
Code of Federal Regulations, 2014 CFR
2014-10-01
... distances between radioactive materials and spaces regularly occupied by crew members or passengers, or... or YELLOW-III packages or overpacks must not be transported in spaces occupied by passengers, except... regularly occupied spaces or living quarters; or (2) For one or more consignments of Class 7 (radioactive...
Rail vs truck transport of biomass.
Mahmudi, Hamed; Flynn, Peter C
2006-01-01
This study analyzes the economics of transshipping biomass from truck to train in a North American setting. Transshipment will only be economic when the cost per unit distance of a second transportation mode is less than the original mode. There is an optimum number of transshipment terminals which is related to biomass yield. Transshipment incurs incremental fixed costs, and hence there is a minimum shipping distance for rail transport above which lower costs/km offset the incremental fixed costs. For transport by dedicated unit train with an optimum number of terminals, the minimum economic rail shipping distance for straw is 170 km, and for boreal forest harvest residue wood chips is 145 km. The minimum economic shipping distance for straw exceeds the biomass draw distance for economically sized centrally located power plants, and hence the prospects for rail transport are limited to cases in which traffic congestion from truck transport would otherwise preclude project development. Ideally, wood chip transport costs would be lowered by rail transshipment for an economically sized centrally located power plant, but in a specific case in Alberta, Canada, the layout of existing rail lines precludes a centrally located plant supplied by rail, whereas a more versatile road system enables it by truck. Hence for wood chips as well as straw the economic incentive for rail transport to centrally located processing plants is limited. Rail transshipment may still be preferred in cases in which road congestion precludes truck delivery, for example as result of community objections.
NASA Astrophysics Data System (ADS)
Cheng, Shaoyong; Xiu, Shixin; Wang, Jimei; Shen, Zhengchao
2006-11-01
The greenhouse effect of SF6 is a great concern today. The development of high voltage vacuum circuit breakers becomes more important. The vacuum circuit breaker has minimum pollution to the environment. The vacuum interrupter is the key part of a vacuum circuit breaker. The interrupting characteristics in vacuum and arc-controlling technique are the main problems to be solved for a longer gap distance in developing high voltage vacuum interrupters. To understand the vacuum arc characteristics and provide effective technique to control vacuum arc in a long gap distance, the arc mode transition of a cup-type axial magnetic field electrode is observed by a high-speed charge coupled device (CCD) video camera under different gap distances while the arc voltage and arc current are recorded. The controlling ability of the axial magnetic field on vacuum arc obviously decreases when the gap distance is longer than 40 mm. The noise components and mean value of the arc voltage significantly increase. The effective method for controlling the vacuum arc characteristics is provided by long gap distances based on the test results. The test results can be used as a reference to develop high voltage and large capacity vacuum interrupters.
Seymour, Christopher W; Kahn, Jeremy M; Schwab, C William; Fuchs, Barry D
2008-01-01
Introduction Patients triaged to tertiary care centers frequently undergo rotary-wing transport and may be exposed to additional risk for adverse events. The incidence of physiologic adverse events and their predisposing factors in mechanically ventilated patients undergoing aeromedical transport are unknown. Methods We performed a retrospective review of flight records of all interfacility, rotary-wing transports to a tertiary care, university hospital during 2001 to 2003. All patients receiving mechanical ventilation via endotracheal tube or tracheostomy were included; trauma, scene flights, and fixed transports were excluded. Data were abstracted from patient flight and hospital records. Adverse events were classified as either major (death, arrest, pneumothorax, or seizure) or minor (physiologic decompensation, new arrhythmia, or requirement for new sedation/paralysis). Bivariate associations between hospital and flight characteristics and the presence of adverse events were examined. Results Six hundred eighty-two interfacility flights occurred during the period of review, with 191 patients receiving mechanical ventilation. Fifty-eight different hospitals transferred patients, with diagnoses that were primarily cardiopulmonary (45%) and neurologic (37%). Median flight distance and time were 42 (31 to 83) km and 13 (8 to 22) minutes, respectively. No major adverse events occurred during flight. Forty patients (22%) experienced a minor physiologic adverse event. Vasopressor requirement prior to flight and flight distance were associated with the presence of adverse events in-flight (P < 0.05). Patient demographics, time of day, season, transferring hospital characteristics, and ventilator settings before and during flight were not associated with adverse events. Conclusion Major adverse events are rare during interfacility, rotary-wing transfer of critically ill, mechanically ventilated patients. Patients transferred over a longer distance or transferred on
Reactive transport of uranium in fractured crystalline rock: Upscaling in time and distance
Dittrich, Timothy M.; Reimus, Paul W.
2015-09-29
In this study, batch adsorption and breakthrough column experiments were conducted to evaluate uranium transport through altered material that fills fractures in a granite rock system at the Grimsel Test Site in Switzerland at pH 6.9 and 7.9. The role of adsorption and desorption kinetics was evaluated with reactive transport modeling by comparing one-, two-, and three-site models. Emphasis was placed on describing long desorption tails that are important for upscaling in time and distance. The effect of increasing pH in injection solutions was also evaluated. For pH 6.9, a three-site model with forward rate constants between 0.07 and 0.8more » ml g –1 h –1, reverse rate constants between 0.001 and 0.06 h –1, and site densities of 1.3, 0.104, and 0.026 μmol g –1 for ‘weak/fast’, ‘strong/slow’, and ‘very strong/very slow’ sites provided the best fits. For pH 7.9, a three-site model with forward rate constants between 0.05 and 0.8 mL g –1 h –1, reverse rate constants between 0.001 and 0.6 h –1, and site densities of 1.3, 0.039, and 0.013 μmol g –1 for a ‘weak/fast’, ‘strong/slow’, and ‘very strong/very slow’ sites provided the best fits. Column retardation coefficients (R d) were 80 for pH 6.9 and 10.3 for pH 7.9. Model parameters determined from the batch and column experiments were used in 50 year large-scale simulations for continuous and pulse injections and indicated that a three-site model is necessary at pH 6.9, although a K d-type equilibrium partition model with one-site was adequate for large scale predictions at pH 7.9. Batch experiments were useful for predicting early breakthrough times in the columns while column experiments helped differentiate the relative importance of sorption sites and desorption rate constants on transport.« less
Travel Distance and the Use of Inpatient Care among Patients with Schizophrenia
Hemenway, David; Kawachi, Ichiro; Subramanian, S. V.; Chen, Wei J.
2009-01-01
This study examines the variations in the use of inpatient care that can be explained by travel distance among patients with schizophrenia living in Taiwan. Data were drawn from the Psychiatric Inpatient Medical Claims Database. We used mediation analysis and multilevel analysis to identify associations. Travel distance did not significantly account for lower readmission rates after an index admission, but significantly explained the longer length of stay of an index admission by 9.3 days (P < 0.001, 85% of variation) between remote and non-remote regions. Policies are discussed aimed at reducing the impact of travel distance on rural mental health care through inter-disciplinary collaboration and telepsychiatry. PMID:18512144
The Effects of Long Distance Running on Preadolescent Children.
ERIC Educational Resources Information Center
Covington, N. Kay
This study investigated the effects of selected physiological variables on preadolescent male and female long distance runners. The trained group was comprised of 20 children between the ages of 8 and 10 who had been running a minimum of 20 miles per week for two months or longer. The control group was made up of 20 children of the same ages who…
Gottschlich, Carsten; Schuhmacher, Dominic
2014-01-01
Finding solutions to the classical transportation problem is of great importance, since this optimization problem arises in many engineering and computer science applications. Especially the Earth Mover's Distance is used in a plethora of applications ranging from content-based image retrieval, shape matching, fingerprint recognition, object tracking and phishing web page detection to computing color differences in linguistics and biology. Our starting point is the well-known revised simplex algorithm, which iteratively improves a feasible solution to optimality. The Shortlist Method that we propose substantially reduces the number of candidates inspected for improving the solution, while at the same time balancing the number of pivots required. Tests on simulated benchmarks demonstrate a considerable reduction in computation time for the new method as compared to the usual revised simplex algorithm implemented with state-of-the-art initialization and pivot strategies. As a consequence, the Shortlist Method facilitates the computation of large scale transportation problems in viable time. In addition we describe a novel method for finding an initial feasible solution which we coin Modified Russell's Method.
Gottschlich, Carsten; Schuhmacher, Dominic
2014-01-01
Finding solutions to the classical transportation problem is of great importance, since this optimization problem arises in many engineering and computer science applications. Especially the Earth Mover's Distance is used in a plethora of applications ranging from content-based image retrieval, shape matching, fingerprint recognition, object tracking and phishing web page detection to computing color differences in linguistics and biology. Our starting point is the well-known revised simplex algorithm, which iteratively improves a feasible solution to optimality. The Shortlist Method that we propose substantially reduces the number of candidates inspected for improving the solution, while at the same time balancing the number of pivots required. Tests on simulated benchmarks demonstrate a considerable reduction in computation time for the new method as compared to the usual revised simplex algorithm implemented with state-of-the-art initialization and pivot strategies. As a consequence, the Shortlist Method facilitates the computation of large scale transportation problems in viable time. In addition we describe a novel method for finding an initial feasible solution which we coin Modified Russell's Method. PMID:25310106
Potential role of sea spray generation in the atmospheric transport of perfluorocarboxylic acids.
Webster, Eva; Ellis, David A
2010-08-01
The observed environmental concentrations of perfluorooctanoic acid (PFOA) and its conjugate base (PFO) in remote regions such as the Arctic have been primarily ascribed to the atmospheric transport and degradation of fluorotelomer alcohols (FTOHs) and to direct PFO transport in ocean currents. These mechanisms are each capable of only partially explaining observations. Transport within marine aerosols has been proposed and may explain transport over short distances but will contribute little over longer distances. However, PFO(A) has been shown to have a very short half-life in aqueous aerosols and thus sea spray was proposed as a mechanism for the generation of PFOA in the gas phase from PFO in a water body. Using the observed PFO concentrations in oceans of the Northern Hemisphere and estimated spray generation rates, this mechanism is shown to have the potential for contributing large amounts of PFOA to the atmosphere and may therefore contribute significantly to the concentrations observed in remote locations. Specifically, the rate of PFOA release into the gas phase from oceans in the Northern Hemisphere is calculated to be potentially comparable to global stack emissions to the atmosphere. The subsequent potential for atmospheric degradation of PFOA and its global warming potential are considered. Observed isomeric ratios and predicted atmospheric concentrations due to FTOH degradation are used to elucidate the likely relative importance of transport pathways. It is concluded that gas phase PFOA released from oceans may help to explain observed concentrations in remote regions. The model calculations performed in the present study strongly suggest that oceanic aerosol and gas phase field monitoring is of vital importance to obtain a complete understanding of the global dissemination of PFCAs. Copyright 2010 SETAC
USDA-ARS?s Scientific Manuscript database
The relationship between colony size and foraging distance was examined in extended foraging arenas with incipient colonies of the Formosan subterranean termite, Coptotermes formosanus Shiraki. Our results showed that as long as the royal pairs are present, larger colonies foraged at longer distance...
2D Perovskites with Short Interlayer Distance for High-Performance Solar Cell Application.
Ma, Chunqing; Shen, Dong; Ng, Tsz-Wai; Lo, Ming-Fai; Lee, Chun-Sing
2018-05-01
2D perovskites have emerged as one of the most promising photovoltaic materials owing to their excellent stability compared with their 3D counterparts. However, in typical 2D perovskites, the highly conductive inorganic layers are isolated by large organic cations leading to quantum confinement and thus inferior electrical conductivity across layers. To address this issue, the large organic cations are replaced with small propane-1,3-diammonium (PDA) cations to reduce distance between the inorganic perovskite layers. As shown by optical characterizations, quantum confinement is no longer dominating in the PDA-based 2D perovskites. This leads to considerable enhancement of charge transport as confirmed with electrochemical impedance spectroscopy, time-resolved photoluminescence, and mobility measurements. The improved electric properties of the interlayer-engineered 2D perovskites yield a power conversion efficiency of 13.0%. Furthermore, environmental stabilities of the PDA-based 2D perovskites are improved. PDA-based 2D perovskite solar cells (PSCs) with encapsulation can retain over 90% of their efficiency upon storage for over 1000 h, and PSCs without encapsulation can maintain their initial efficiency at 70 °C for over 100 h, which exhibit promising stabilities. These results reveal excellent optoelectronic properties and intrinsic stabilities of the layered perovskites with reduced interlayer distance. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Cab signals controlled in accordance with block conditions stopping distance in advance. 236.511 Section 236.511 Transportation Other Regulations Relating to... § 236.511 Cab signals controlled in accordance with block conditions stopping distance in advance. The...
Merrild, Hanna; Larsen, Anna W; Christensen, Thomas H
2012-05-01
Recycling of materials from municipal solid waste is commonly considered to be superior to any other waste treatment alternative. For the material fractions with a significant energy content this might not be the case if the treatment alternative is a waste-to-energy plant with high energy recovery rates. The environmental impacts from recycling and from incineration of six material fractions in household waste have been compared through life cycle assessment assuming high-performance technologies for material recycling as well as for waste incineration. The results showed that there are environmental benefits when recycling paper, glass, steel and aluminium instead of incinerating it. For cardboard and plastic the results were more unclear, depending on the level of energy recovery at the incineration plant, the system boundaries chosen and which impact category was in focus. Further, the environmental impact potentials from collection, pre-treatment and transport was compared to the environmental benefit from recycling and this showed that with the right means of transport, recyclables can in most cases be transported long distances. However, the results also showed that recycling of some of the material fractions can only contribute marginally in improving the overall waste management system taking into consideration their limited content in average Danish household waste. Copyright © 2012 Elsevier Ltd. All rights reserved.
Effects of target distance on select biomechanical parameters in taekwondo roundhouse kick.
Falco, Coral; Molina-García, Javier; Alvarez, Octavio; Estevan, Isaac
2013-11-01
The aim of this study was to investigate the effects of target distance on temporal and impact force parameters that are important performance factors in taekwondo kicks. Forty-nine taekwondo athletes (age = 24.5 +/- 5.9 years; mass = 79.9 +/- 10.8 kg) were recruited: 13 male experts, 21 male novices, 8 female experts, and 6 female novices. Impact force, reaction time, and execution time were computed. Three-way repeated measure ANOVAs revealed significant 'distance' effect on impact force, reaction time, and execution time (p = 0.001). Comparisons between distance conditions revealed that taekwondo athletes kicked with higher impact force from short distance (17.6 +/- 7.5 N/kg) than from long distance (13.1 +/- 5.7 N/kg) (p < 0.001), had lower reaction time from short distance (498 +/- 90 ms) and normal distance (521 +/- 111 ms) than from long distance (602 +/- 121 ms) (p < 0.001), and had lower execution time from short distance (261 +/- 69 ms/m) than from normal distance (306 +/- 105 ms/m) or from long distance (350 +/- 106 ms/m) (p = 0.003 and p < 0.001, respectively). In conclusion, target distance affected the kick performance; as distance increases, impact force decreased and reaction time increased. Therefore, when reaction to a simple visual stimulus is needed, kicking from a long distance is not recommended, as longer time is required to respond.
Li, Hongyi; Yang, Chongqing; Lu, Kuiyuan; Zhang, Liyang; Yang, Jiefu; Wang, Fang; Liu, Dongge; Cui, Di; Sun, Mingjun; Pang, Jianxin; Dai, Luru; Han, Dong; Liao, Fulong
2016-10-05
Although the microcirculatory dysfunctions of edema formation are well documented, the draining pattern of dermal edema lacks information. This study was to assess the potential drainage pathways of the interstitial fluid in patients with ankle edema using the anatomical and histological methods. Four amputees of lower leg participated in this study. Fluorescent imaging agent was injected into lateral ankle dermis in one volunteered patient before the amputation and three lower legs after the amputation. Physiologically in the volunteer or enhanced by cyclical compression on three amputated limbs, several fluorescent longitudinal pathways from ankle dermis to the broken end of the amputated legs were subsequently visualized and studied using histological methods, laser confocal microscopy and electron microscopy methods respectively. Interestingly, the fluorescent pathways confirmed to be fibrous connective tissues and the presence of two types: those of the cutaneous pathway (located in dermis or the interlobular septum among adipose tissues within the hypodermis) and those of the perivascular pathway (located in connective tissues surrounding the veins and the arteries). The intrinsic three-dimensional architecture of each fluorescent pathway was the longitudinally running and interconnected fibril bundles, upon which, an interfacial transport pathway within connective tissues was visualized by fluorescein. The current anatomical data suggested that a unique long-distance transport pathway composed of oriented fibrous connective tissues might play a pathophysiological role in draining dermal edema besides vascular circulations and provide novel understandings of general fibrous connective tissues in life science.
Long-distance transport of signals during symbiosis
Xie, Zhi-Ping; Illana, Antonio
2011-01-01
Legumes enter nodule symbioses with nitrogen-fixing bacteria (rhizobia), whereas most flowering plants establish symbiotic associations with arbuscular mycorrhizal (AM) fungi. Once first steps of symbiosis are initiated, nodule formation and mycorrhization in legumes is negatively controlled by a shoot-derived inhibitor (SDI), a phenomenon termed autoregulation. According to current views, autoregulation of nodulation and mycorrhization in legumes is regulated in a similar way. CLE peptides induced in response to rhizobial nodulation signals (Nod factors) have been proposed to represent the ascending long-distance signals to the shoot. Although not proven yet, these CLE peptides are likely perceived by leucine-rich repeat (LRR) autoregulation receptor kinases in the shoot. Autoregulation of mycorrhization in non-legumes is reminiscent to the phenomenon of “systemic acquired resistance” in plant-pathogen interactions. PMID:21455020
Pagabeleguem, Soumaïla; Seck, Momar Talla; Sall, Baba; Vreysen, Marc J B; Gimonneau, Geoffrey; Fall, Assane Gueye; Bassene, Mireille; Sidibé, Issa; Rayaissé, Jean-Baptiste; Belem, Adrien M G; Bouyer, Jérémy
2015-05-01
The application of the sterile insect technique (SIT) requires mass-production of sterile males of good biological quality. The size of the project area will in most cases determine whether it is more cost effective to produce the sterile flies locally (and invest in a mass-rearing facility) or import the sterile flies from a mass-rearing facility that is located in another country. This study aimed at assessing the effect of long distance transport of sterile male Glossina palpalis gambiensis pupae on adult male fly yield. The male pupae were produced at the Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso, and shipped with a commercial courier service in insulated transport boxes at a temperature of ±10°C to Senegal (±36 h of transport). Upon arrival in the insectary in Dakar, the pupae were transferred to an emergence room and the flies monitored for 3-6 days. The results showed that the used system of isothermal boxes that contained phase change material packs (S8) managed to keep the temperature at around 10°C which prevented male fly emergence during transport. The emergence rate was significantly higher for pupae from batch 2 (chilled at 4°C for one day in the source insectary before transport) than those from batch 1 (chilled at 4°C for two days in the source insectary before transport) i.e. an average (±sd) of 76.1 ± 13.2% and 72.2 ± 14.3%, respectively with a small proportion emerging during transport (0.7 ± 1.7% and 0.9 ± 2.9%, respectively). Among the emerged flies, the percentage with deformed (not fully expanded) wings was significantly higher for flies from batch 1 (12.0 ± 6.3%) than from batch 2 (10.7 ± 7.5%). The amount of sterile males available for release as a proportion of the total pupae shipped was 65.8 ± 13.3% and 61.7 ± 14.7% for batch 1 and 2 pupae, respectively. The results also showed that the temperature inside the
23 CFR 750.103 - Measurements of distance.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 23 Highways 1 2012-04-01 2012-04-01 false Measurements of distance. 750.103 Section 750.103 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RIGHT-OF-WAY AND ENVIRONMENT HIGHWAY BEAUTIFICATION National Standards for Regulation by States of Outdoor Advertising Adjacent to the Interstate...
Transportation statistics annual report 1998 : long distance travel and freight
DOT National Transportation Integrated Search
1998-01-01
This Transportation Statistics Annual Report 1998 is the fifth annual report prepared by the Bureau of Transportation Statistics (BTS), as required by law [49 U.S.C. 111 (j)]. As in prior years, the report brings together under one cover information ...
DISTANCES TO DARK CLOUDS: COMPARING EXTINCTION DISTANCES TO MASER PARALLAX DISTANCES
DOE Office of Scientific and Technical Information (OSTI.GOV)
Foster, Jonathan B.; Jackson, James M.; Stead, Joseph J.
We test two different methods of using near-infrared extinction to estimate distances to dark clouds in the first quadrant of the Galaxy using large near-infrared (Two Micron All Sky Survey and UKIRT Infrared Deep Sky Survey) surveys. Very long baseline interferometry parallax measurements of masers around massive young stars provide the most direct and bias-free measurement of the distance to these dark clouds. We compare the extinction distance estimates to these maser parallax distances. We also compare these distances to kinematic distances, including recent re-calibrations of the Galactic rotation curve. The extinction distance methods agree with the maser parallax distancesmore » (within the errors) between 66% and 100% of the time (depending on method and input survey) and between 85% and 100% of the time outside of the crowded Galactic center. Although the sample size is small, extinction distance methods reproduce maser parallax distances better than kinematic distances; furthermore, extinction distance methods do not suffer from the kinematic distance ambiguity. This validation gives us confidence that these extinction methods may be extended to additional dark clouds where maser parallaxes are not available.« less
Effect of fuel concentration and force on collective transport by a team of dynein motors
Takshak, Anjneya; Roy, Tanushree; Tandaiya, Parag
2016-01-01
Abstract Motor proteins are essential components of intracellular transport inside eukaryotic cells. These protein molecules use chemical energy obtained from hydrolysis of ATP to produce mechanical forces required for transporting cargos inside cells, from one location to another, in a directed manner. Of these motors, cytoplasmic dynein is structurally more complex than other motor proteins involved in intracellular transport, as it shows force and fuel (ATP) concentration dependent step‐size. Cytoplasmic dynein motors are known to work in a team during cargo transport and force generation. Here, we use a complete Monte‐Carlo model of single dynein constrained by in vitro experiments, which includes the effect of both force and ATP on stepping as well as detachment of motors under force. We then use our complete Monte‐Carlo model of single dynein motor to understand collective cargo transport by a team of dynein motors, such as dependence of cargo travel distance and velocity on applied force and fuel concentration. In our model, cargos pulled by a team of dynein motors do not detach rapidly under higher forces, confirming the experimental observation of longer persistence time of dynein team on microtubule under higher forces. PMID:27727483
Transport Equation Based Wall Distance Computations Aimed at Flows With Time-Dependent Geometry
NASA Technical Reports Server (NTRS)
Tucker, Paul G.; Rumsey, Christopher L.; Bartels, Robert E.; Biedron, Robert T.
2003-01-01
Eikonal, Hamilton-Jacobi and Poisson equations can be used for economical nearest wall distance computation and modification. Economical computations may be especially useful for aeroelastic and adaptive grid problems for which the grid deforms, and the nearest wall distance needs to be repeatedly computed. Modifications are directed at remedying turbulence model defects. For complex grid structures, implementation of the Eikonal and Hamilton-Jacobi approaches is not straightforward. This prohibits their use in industrial CFD solvers. However, both the Eikonal and Hamilton-Jacobi equations can be written in advection and advection-diffusion forms, respectively. These, like the Poisson s Laplacian, are commonly occurring industrial CFD solver elements. Use of the NASA CFL3D code to solve the Eikonal and Hamilton-Jacobi equations in advective-based forms is explored. The advection-based distance equations are found to have robust convergence. Geometries studied include single and two element airfoils, wing body and double delta configurations along with a complex electronics system. It is shown that for Eikonal accuracy, upwind metric differences are required. The Poisson approach is found effective and, since it does not require offset metric evaluations, easiest to implement. The sensitivity of flow solutions to wall distance assumptions is explored. Generally, results are not greatly affected by wall distance traits.
Transport Equation Based Wall Distance Computations Aimed at Flows With Time-Dependent Geometry
NASA Technical Reports Server (NTRS)
Tucker, Paul G.; Rumsey, Christopher L.; Bartels, Robert E.; Biedron, Robert T.
2003-01-01
Eikonal, Hamilton-Jacobi and Poisson equations can be used for economical nearest wall distance computation and modification. Economical computations may be especially useful for aeroelastic and adaptive grid problems for which the grid deforms, and the nearest wall distance needs to be repeatedly computed. Modifications are directed at remedying turbulence model defects. For complex grid structures, implementation of the Eikonal and Hamilton-Jacobi approaches is not straightforward. This prohibits their use in industrial CFD solvers. However, both the Eikonal and Hamilton-Jacobi equations can be written in advection and advection-diffusion forms, respectively. These, like the Poisson's Laplacian, are commonly occurring industrial CFD solver elements. Use of the NASA CFL3D code to solve the Eikonal and Hamilton-Jacobi equations in advective-based forms is explored. The advection-based distance equations are found to have robust convergence. Geometries studied include single and two element airfoils, wing body and double delta configurations along with a complex electronics system. It is shown that for Eikonal accuracy, upwind metric differences are required. The Poisson approach is found effective and, since it does not require offset metric evaluations, easiest to implement. The sensitivity of flow solutions to wall distance assumptions is explored. Generally, results are not greatly affected by wall distance traits.
Study on a neon cryogenic oscillating heat pipe with long heat transport distance
NASA Astrophysics Data System (ADS)
Liang, Qing; Li, Yi; Wang, Qiuliang
2018-06-01
An experimental study is carried out to study the heat transfer characteristics of a cryogenic oscillating heat pipe (OHP) with long heat transport distance. The OHP is made up of a capillary tube with an inner diameter of 1.0 mm and an outer diameter of 2.0 mm. The working fluid is neon, and the length of the adiabatic section is 480 mm. Tests are performed with the different heat inputs, liquid filling ratios and condenser temperature. For the cryogenic OHP with a liquid filling ratio of 30.7% at the condenser temperature of 28 K, the effective thermal conductivity is 3466-30,854 W/m K, and the maximum transfer power is 35.60 W. With the increment of the heat input, the effective thermal conductivity of the cryogenic OHP increases at the liquid filling ratios of 30.7% and 38.5%, while it first increases and then decreases at the liquid filling ratios of 15.2% and 23.3%. Moreover, the effective thermal conductivity increases with decreasing liquid filling ratio at the small heat input, and the maximum transfer power first increases and then decreases with increasing liquid filling ratio. Finally, it is found that the thermal performance of the cryogenic OHP can be improved by increasing the condenser temperature.
49 CFR 236.531 - Trip arm; height and distance from rail.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Trip arm; height and distance from rail. 236.531... Train Stop, Train Control and Cab Signal Systems Rules and Instructions; Roadway § 236.531 Trip arm; height and distance from rail. Trip arm of automatic train stop device when in the stop position shall be...
49 CFR 236.531 - Trip arm; height and distance from rail.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Trip arm; height and distance from rail. 236.531... Train Stop, Train Control and Cab Signal Systems Rules and Instructions; Roadway § 236.531 Trip arm; height and distance from rail. Trip arm of automatic train stop device when in the stop position shall be...
49 CFR 236.531 - Trip arm; height and distance from rail.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Trip arm; height and distance from rail. 236.531... Train Stop, Train Control and Cab Signal Systems Rules and Instructions; Roadway § 236.531 Trip arm; height and distance from rail. Trip arm of automatic train stop device when in the stop position shall be...
49 CFR 236.531 - Trip arm; height and distance from rail.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Trip arm; height and distance from rail. 236.531... Train Stop, Train Control and Cab Signal Systems Rules and Instructions; Roadway § 236.531 Trip arm; height and distance from rail. Trip arm of automatic train stop device when in the stop position shall be...
49 CFR 236.531 - Trip arm; height and distance from rail.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Trip arm; height and distance from rail. 236.531... Train Stop, Train Control and Cab Signal Systems Rules and Instructions; Roadway § 236.531 Trip arm; height and distance from rail. Trip arm of automatic train stop device when in the stop position shall be...
Does Travel Distance Affect Readmission Rates after Cardiac Surgery?
Juo, Yen-Yi; Woods, Alexis; Ou, Ryan; Ramos, Gianna; Shemin, Richard; Benharash, Peyman
2017-10-01
With emphasis on value-based health care, empiric models are used to estimate expected readmission rates for individual institutions. The aim of this study was to determine the relationship between distance traveled to seek surgical care and likelihood of readmission in adult patients undergoing cardiac operations at a single medical center. All adults undergoing major cardiac surgeries from 2008 to 2015 were included. Patients were stratified by travel distance into regional and distant travel groups. Multivariable logistic regression models were developed to assess the impact of distance traveled on odds of readmission. Of the 4232 patients analyzed, 29 per cent were in the regional group and 71 per cent in the distant. Baseline characteristics between the two groups were comparable except mean age (62 vs 61 years, P < 0.01) and Caucasian race (59 vs 73%, P < 0.01). Distant travel was associated with a significantly longer hospital length of stay (11.8 vs 10.5 days, P < 0.01) and lower risk of readmission (9.5 vs 13.4%, P < 0.01). Odds of readmission was inversely associated with logarithm of distance traveled (odds ratio 0.75). Travel distance in patients undergoing major cardiac surgeries was inversely associated with odds of readmission.
Extensive electron transport and energization via multiple, localized dipolarizing flux bundles
NASA Astrophysics Data System (ADS)
Gabrielse, Christine; Angelopoulos, Vassilis; Harris, Camilla; Artemyev, Anton; Kepko, Larry; Runov, Andrei
2017-05-01
Using an analytical model of multiple dipolarizing flux bundles (DFBs) embedded in earthward traveling bursty bulk flows, we demonstrate how equatorially mirroring electrons can travel long distances and gain hundreds of keV from betatron acceleration. The model parameters are constrained by four Time History of Events and Macroscale Interactions during Substorms satellite observations, putting limits on the DFBs' speed, location, and magnetic and electric field magnitudes. We find that the sharp, localized peaks in magnetic field have such strong spatial gradients that energetic electrons ∇B drift in closed paths around the peaks as those peaks travel earthward. This is understood in terms of the third adiabatic invariant, which remains constant when the field changes on timescales longer than the electron's drift timescale: An energetic electron encircles a sharp peak in magnetic field in a closed path subtending an area of approximately constant flux. As the flux bundle magnetic field increases the electron's drift path area shrinks and the electron is prevented from escaping to the ambient plasma sheet, while it continues to gain energy via betatron acceleration. When the flux bundles arrive at and merge with the inner magnetosphere, where the background field is strong, the electrons suddenly gain access to previously closed drift paths around the Earth. DFBs are therefore instrumental in transporting and energizing energetic electrons over long distances along the magnetotail, bringing them to the inner magnetosphere and energizing them by hundreds of keV.
Najafi, Bijan; Khan, Tahir; Fleischer, Adam; Wrobel, James
2013-01-01
We explored gait differences in patients with diabetes and peripheral neuropathy (DPN) and aged-matched controls over short and long walking distances. The potential benefit of footwear for improving gait in patients with DPN was also explored. Twelve patients with DPN and eight controls walked at their habitual speed over short (7 m) and long (20 m) distances under two conditions: barefoot and regular shoes. A validated system of body-worn sensors was used to extract spatiotemporal gait parameters. Neuropathy severity was quantified using vibratory perception threshold measured at the great toe. Gait deterioration in the DPN group was observed during all of the walking trials. However, the difference between patients with DPN and participants in the control group achieved statistical significance only during long walking distance trials. Shod and barefoot double support times were longer in the DPN group during long walking distances (>20%, P = .03). Gait unsteadiness, defined as coefficient of variation of gait velocity, was also significantly higher in the DPN group when barefoot walking over long distances (83%, P = .008). Furthermore, there was a high correlation between neuropathy severity and gait unsteadiness best demonstrated during the barefoot walking/long walking distance condition (r = 0.77, P < .001). The addition of footwear improved gait steadiness in the DPN group by 46% (P = .02). All differences were independent of age, sex, and body mass index (P > .05). This study suggests that gait alteration in patients with DPN is most pronounced while walking barefoot over longer distances and that footwear may improve gait steadiness in patients with DPN.
Lyons, Rebecca; Van de Bittner, Kyle; Morgan-Jones, Sean
2014-12-01
Dust and particulate distribution patterns are shifting as global climate change brings about longer drought periods. Particulates act as vehicles for long range transport of organic pollutants, depositing at locations far from their source. Nonylphenol, a biodegradation product of nonylphenol polyethoxylate, is a known endocrine disruptor. Nonylphenol polyethoxylate enters the environment as an inert ingredient in pesticide sprays, potentially traveling great distances from its application site. This is of concern when a highly agricultural region, California's Central Valley, lies adjacent to sensitive areas like the Eastern Sierra Nevada Mountains. The distribution and transport mechanisms for 4-nonylphenol were investigated in Eastern Sierra Nevada canyons. Regions close to canyon headwalls showed trace amounts of 4-nonylphenol in surface water, snow, and atmospheric deposition. Exposed areas had yearly average concentrations as high as 9 μg/L. Distribution patterns are consistent with particulate-bound transport. This suggests with increasing drought periods, higher levels of persistent organic pollutants are likely. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Lanyi, Janos K.
1977-01-01
Cell envelope vesicles prepared from H. halobium contain bacteriorhodopsin and upon illumination protons are ejected. Coupled to the proton motive force is the efflux of Na(+). Measurements of Na-22 flux, exterior pH change, and membrane potential, Delta(psi) (with the dye 3,3'-dipentyloxadicarbocyanine) indicate that the means of Na(+) transport is sodium/proton exchange. The kinetics of the pH changes and other evidence suggests that the antiport is electrogenic (H(+)/Na(++ greater than 1). The resulting large chemical gradient for Na(+) (outside much greater than inside), as well as the membrane potential, will drive the transport of 18 amino acids. The I9th, glutamate, is unique in that its accumulation is indifferent to Delta(psi): this amino acid is transported only when a chemical gradient for Na(+) is present. Thus, when more and more NaCl is included in the vesicles glutamate transport proceeds with longer and longer lags. After illumination the gradient of H+() collapses within 1 min, while the large Na(+) gradient and glutamate transporting activity persists for 10- 15 min, indicating that proton motive force is not necessary for transport. A chemical gradient of Na(+), arranged by suspending vesicles loaded with KCl in NaCl, drives glutamate transport in the dark without other sources of energy, with V(sub max) and K(sub m) comparable to light-induced transport. These and other lines of evidence suggest that the transport of glutamate is facilitated by symport with Na(+), in an electrically neutral fashion, so that only the chemical component of the Na(+) gradient is a driving force.
Kangaroo transport instead of incubator transport.
Sontheimer, Dieter; Fischer, Christine B; Buch, Kerstin E
2004-04-01
Compared with in utero transport, incubator transport for preterm infants has several disadvantages including instability during transport with increased mortality and morbidity, lack of adequate systems for securing the infant in the event of an accident, and separation of mother and infant. As a new kind of postnatal transportation that bears some analogy to in utero transport and may be safer than incubator transport, we investigated kangaroo transport, transporting the infant on the mother's or other caregiver's chest. This article presents a description and preliminary data for kangaroo transport. We conducted kangaroo transports of 31 stable preterm and term infants in different settings and recorded data regarding transport conditions and cardiorespiratory stability. Eighteen transports were back transfers, and 13 were transfers in. Twenty-seven transports were conducted by the mother, 1 by the father, 2 by nurses, and 1 by a doctor. Transport distance was 2 to 400 km. Heart rate, respiratory rate, oxygen saturation, and rectal temperature remained stable during all kangaroo transports lasting 10 to 300 minutes. Weight at transport was 1220 to 3720 g. Parents felt very comfortable and safe and appreciated this method of transport. Kangaroo transport promotes mother-infant closeness and might ameliorate several of the risks associated with incubator transport.
Multi-image acquisition-based distance sensor using agile laser spot beam.
Riza, Nabeel A; Amin, M Junaid
2014-09-01
We present a novel laser-based distance measurement technique that uses multiple-image-based spatial processing to enable distance measurements. Compared with the first-generation distance sensor using spatial processing, the modified sensor is no longer hindered by the classic Rayleigh axial resolution limit for the propagating laser beam at its minimum beam waist location. The proposed high-resolution distance sensor design uses an electronically controlled variable focus lens (ECVFL) in combination with an optical imaging device, such as a charged-coupled device (CCD), to produce and capture different laser spot size images on a target with these beam spot sizes different from the minimal spot size possible at this target distance. By exploiting the unique relationship of the target located spot sizes with the varying ECVFL focal length for each target distance, the proposed distance sensor can compute the target distance with a distance measurement resolution better than the axial resolution via the Rayleigh resolution criterion. Using a 30 mW 633 nm He-Ne laser coupled with an electromagnetically actuated liquid ECVFL, along with a 20 cm focal length bias lens, and using five spot images captured per target position by a CCD-based Nikon camera, a proof-of-concept proposed distance sensor is successfully implemented in the laboratory over target ranges from 10 to 100 cm with a demonstrated sub-cm axial resolution, which is better than the axial Rayleigh resolution limit at these target distances. Applications for the proposed potentially cost-effective distance sensor are diverse and include industrial inspection and measurement and 3D object shape mapping and imaging.
Detecting changes in forced climate attractors with Wasserstein distance
NASA Astrophysics Data System (ADS)
Robin, Yoann; Yiou, Pascal; Naveau, Philippe
2017-07-01
The climate system can been described by a dynamical system and its associated attractor. The dynamics of this attractor depends on the external forcings that influence the climate. Such forcings can affect the mean values or variances, but regions of the attractor that are seldom visited can also be affected. It is an important challenge to measure how the climate attractor responds to different forcings. Currently, the Euclidean distance or similar measures like the Mahalanobis distance have been favored to measure discrepancies between two climatic situations. Those distances do not have a natural building mechanism to take into account the attractor dynamics. In this paper, we argue that a Wasserstein distance, stemming from optimal transport theory, offers an efficient and practical way to discriminate between dynamical systems. After treating a toy example, we explore how the Wasserstein distance can be applied and interpreted to detect non-autonomous dynamics from a Lorenz system driven by seasonal cycles and a warming trend.
Pilkington, Hugo; Blondel, Béatrice; Drewniak, Nicolas; Zeitlin, Jennifer
2014-12-01
The number of maternity units has declined in France, raising concerns about the possible impact of increasing travel distances on perinatal health outcomes. We investigated impact of distance to closest maternity unit on perinatal mortality. Data from the French National Vital Statistics Registry were used to construct foetal and neonatal mortality rates over 2001-08 by distance from mother's municipality of residence and the closest municipality with a maternity unit. Data from French neonatal mortality certificates were used to compute neonatal death rates after out-of-hospital birth. Relative risks by distance were estimated, adjusting for individual and municipal-level characteristics. Seven percent of births occurred to women residing at ≥30 km from a maternity unit and 1% at ≥45 km. Foetal and neonatal mortality rates were highest for women living at <5 km from a maternity unit. For foetal mortality, rates increased at ≥45 km compared with 5-45 km. In adjusted models, long distance to a maternity unit had no impact on overall mortality but women living closer to a maternity unit had a higher risk of neonatal mortality. Neonatal deaths associated with out-of-hospital birth were rare but more frequent at longer distances. At the municipal-level, higher percentages of unemployment and foreign-born residents were associated with increased mortality. Overall mortality was not associated with living far from a maternity unit. Mortality was elevated in municipalities with social risk factors and located closest to a maternity unit, reflecting the location of maternity units in deprived areas with risk factors for poor outcome. © The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association.
Colloid transport in dual-permeability media
NASA Astrophysics Data System (ADS)
Leij, Feike J.; Bradford, Scott A.
2013-07-01
It has been widely reported that colloids can travel faster and over longer distances in natural structured porous media than in uniform structureless media used in laboratory studies. The presence of preferential pathways for colloids in the subsurface environment is of concern because of the increased risks for disease caused by microorganisms and colloid-associated contaminants. This study presents a model for colloid transport in dual-permeability media that includes reversible and irreversible retention of colloids and first-order exchange between the aqueous phases of the two regions. The model may also be used to describe transport of other reactive solutes in dual-permeability media. Analytical solutions for colloid concentrations in aqueous and solid phases were obtained using Laplace transformation and matrix decomposition. The solutions proved convenient to assess the effect of model parameters on the colloid distribution. The analytical model was used to describe effluent concentrations for a bromide tracer and 3.2- or 1-μm-colloids that were observed after transport through a composite 10-cm long porous medium made up of a cylindrical lens or core of sand and a surrounding matrix with sand of a different grain size. The tracer data were described very well and realistic estimates were obtained for the pore-water velocity in the two flow domains. An accurate description was also achieved for most colloid breakthrough curves. Dispersivity and retention parameters were typically greater for the larger 3.2-μm-colloids while both reversible and irreversible retention rates tended to be higher for the finer sands than the coarser sand. The relatively small sample size and the complex flow pattern in the composite medium made it difficult to reach definitive conclusions regarding transport parameters for colloid transport.
Energy transport in cooling device by magnetic fluid
NASA Astrophysics Data System (ADS)
Yamaguchi, Hiroshi; Iwamoto, Yuhiro
2017-06-01
Temperature sensitive magnetic fluid has a great potential with high performance heat transport ability as well as long distance energy (heat) transporting. In the present study experimental set-up was newly designed and constructed in order to measure basic heat transport characteristics under various magnetic field conditions. Angular dependence for the device (heat transfer section) was also taken into consideration for a sake of practical applications. The energy transfer characteristic (heat transport capability) in the magnetically-driven heat transport (cooling) device using the binary TSMF was fully investigated with the set-up. The obtained results indicate that boiling of the organic mixture (before the magnetic fluid itself reaching boiling point) effectively enhances the heat transfer as well as boosting the flow to circulate in the closed loop by itself. A long-distance heat transport of 5 m is experimentally confirmed, transferring the thermal energy of 35.8 W, even when the device (circulation loop) is horizontally placed. The highlighted results reveal that the proposed cooling device is innovative in a sense of transporting substantial amount of thermal energy (heat) as well as a long distance heat transport. The development of the magnetically-driven heat transport device has a great potential to be replaced for the conventional heat pipe in application of thermal engineering.
Thermal energy storage and transport
NASA Technical Reports Server (NTRS)
Hausz, W.
1980-01-01
The extraction of thermal energy from large LWR and coal fired plants for long distance transport to industrial and residential/commercial users is analyzed. Transport of thermal energy as high temperature water is shown to be considerably cheaper than transport as steam, hot oil, or molten salt over a wide temperature range. The delivered heat is competitive with user-generated heat from oil, coal, or electrode boilers at distances well over 50 km when the pipeline operates at high capacity factor. Results indicate that thermal energy storage makes meeting of even very low capacity factor heat demands economic and feasible and gives the utility flexibility to meet coincident electricity and heat demands effectively.
Rapid Water Transport by Long-Lasting Modon Eddy Pairs in the Southern Midlatitude Oceans
NASA Astrophysics Data System (ADS)
Hughes, Chris W.; Miller, Peter I.
2017-12-01
Water in the ocean is generally carried with the mean flow, mixed by eddies, or transported westward by coherent eddies at speeds close to the long baroclinic Rossby wave speed. Modons (dipole eddy pairs) are a theoretically predicted exception to this behavior, which can carry water to the east or west at speeds much larger than the Rossby wave speed, leading to unusual transports of heat, nutrients, and carbon. We provide the first observational evidence of such rapidly moving modons propagating over large distances. These modons are found in the midlatitude oceans around Australia, with one also seen in the South Atlantic west of the Agulhas region. They can travel at more than 10 times the Rossby wave speed of 1-2 cm s-1 and typically persist for about 6 months carrying their unusual water mass properties with them, before splitting into individual vortices, which can persist for many months longer.
Comparison of skid resistance testing to stopping distance testing.
DOT National Transportation Integrated Search
1998-01-01
This report is intended to statistically summarize the results of a side-by-side test of the skid resistance testing trailer utilized by the Oregon Department of Transportation (ODOT), and the stopping distance car utilized by the Oregon State Police...
Slower phloem transport in gymnosperm trees can be attributed to higher sieve element resistance.
Liesche, Johannes; Windt, Carel; Bohr, Tomas; Schulz, Alexander; Jensen, Kaare H
2015-04-01
In trees, carbohydrates produced in photosynthesizing leaves are transported to roots and other sink organs over distances of up to 100 m inside a specialized transport tissue, the phloem. Angiosperm and gymnosperm trees have a fundamentally different phloem anatomy with respect to cell size, shape and connectivity. Whether these differences have an effect on the physiology of carbohydrate transport, however, is not clear. A meta-analysis of the experimental data on phloem transport speed in trees yielded average speeds of 56 cm h(-1) for angiosperm trees and 22 cm h(-1) for gymnosperm trees. Similar values resulted from theoretical modeling using a simple transport resistance model. Analysis of the model parameters clearly identified sieve element (SE) anatomy as the main factor for the significantly slower carbohydrate transport speed inside the phloem in gymnosperm compared with angiosperm trees. In order to investigate the influence of SE anatomy on the hydraulic resistance, anatomical data on SEs and sieve pores were collected by transmission electron microscopy analysis and from the literature for 18 tree species. Calculations showed that the hydraulic resistance is significantly higher in the gymnosperm than in angiosperm trees. The higher resistance is only partially offset by the considerably longer SEs of gymnosperms. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
DeGuzman, Pamela B; Merwin, Elizabeth I; Bourguignon, Cheryl
2013-01-01
The purpose of this research was to determine the impact of two neighborhood walkability (the extent to which the built environment is pedestrian friendly) metrics on health outcomes of women living in low-income urban neighborhoods, both before and after accounting for individual and neighborhood factors. A cross-sectional, retrospective design was used. The sample of 1800 low-income women was drawn from Welfare, Children and Families: A Three-City Study (a study of low-income women from three U.S. cities). Using multilevel modeling and geographic information systems, the study sought to determine the effect of distance to public transportation and residential density on health status, mental health symptoms, and health-related limitations. No significant relationship was found between the two walkability metrics and health outcomes. Instead, neighborhood problems that affect crime and safety impacted health status and mental health symptoms. As cities make changes to the built environment with the hope of affecting residents' health outcomes, public health nurses need to be aware that changing walkability characteristics in a neighborhood may not affect the health of residents of high crime, low-income neighborhoods. Without first addressing neighborhood crime, efforts to improve walkability in low-income neighborhoods may fail. © 2013 Wiley Periodicals, Inc.
Design and Operation of the World's First Long Distance Bauxite Slurry Pipeline
NASA Astrophysics Data System (ADS)
Gandhi, Ramesh; Weston, Mike; Talavera, Maru; Brittes, Geraldo Pereira; Barbosa, Eder
Mineracão Bauxita Paragominas (MBP) is the first long distance slurry pipeline transporting bauxite slurry. Bauxite had developed a reputation for being difficult to hydraulically transport using long distance pipelines. This myth has now been proven wrong. The 245-km- long, 13.5 MTPY capacity MBP pipeline was designed and commissioned by PSI for CVRD. The pipeline is located in the State of Para, Brazil. The Miltonia bauxite mine is in a remote location with no other efficient means of transport. The bauxite slurry is delivered to Alunorte Alumina refinery located near Barcarena. This first of its kind pipeline required significant development work in order to assure technical and economic feasibility. This paper describes the technical aspects of design of the pipeline. It also summarizes the operating experience gained during the first year of operation.
Covault, Jacob A.; Craddock, William H.; Romans, Brian W.; Fildani, Andrea; Gosai, Mayur
2013-01-01
Sediment generation and transport through terrestrial catchments influence soil distribution, geochemical cycling of particulate and dissolved loads, and the character of the stratigraphic record of Earth history. To assess the spatiotemporal variation in landscape evolution, we compare global compilations of stream gauge–derived () and cosmogenic radionuclide (CRN)–derived (predominantly 10Be; ) denudation of catchments (mm/yr) and sediment load of rivers (Mt/yr). Stream gauges measure suspended sediment loads of rivers during several to tens of years, whereas CRNs provide catchment-integrated denudation rates at 102–105-yr time scales. Stream gauge–derived and CRN-derived sediment loads in close proximity to one another (<500 km) exhibit broad similarity ( stream gauge samples; CRN samples). Nearly two-thirds of CRN-derived sediment loads exceed historic loads measured at the same locations (). Excessive longer-term sediment loads likely are a result of longer-term recurrence of large-magnitude sediment-transport events. Nearly 80% of sediment loads measured at approximately the same locations exhibit stream gauge loads that are within an order of magnitude of CRN loads, likely as a result of the buffering capacity of large flood plains. Catchments in which space for deposition exceeds sediment supply have greater buffering capacity. Superior locations in which to evaluate anthropogenic influences on landscape evolution might be buffered catchments, in which temporary storage of sediment in flood plains can provide stream gauge–based sediment loads and denudation rates that are applicable over longer periods than the durations of gauge measurements. The buffering capacity of catchments also has implications for interpreting the stratigraphic record; delayed sediment transfer might complicate the stratigraphic record of external forcings and catchment modification.
Distance dependence in photo-induced intramolecular electron transfer
NASA Astrophysics Data System (ADS)
Larsson, Sven; Volosov, Andrey
1986-09-01
The distance dependence of the rate of photo-induced electron transfer reactions is studied. A quantum mechanical method CNDO/S is applied to a series of molecules recently investigated by Hush et al. experimentally. The calculations show a large interaction through the saturated bridge which connects the two chromophores. The electronic matrix element HAB decreases a factor 10 in about 4 Å. There is also a decrease of the rate due to less exothermicity for the longer molecule. The results are in fair agreement with the experimental results.
The Relative Cost of Biomass Energy Transport
NASA Astrophysics Data System (ADS)
Searcy, Erin; Flynn, Peter; Ghafoori, Emad; Kumar, Amit
Logistics cost, the cost of moving feedstock or products, is a key component of the overall cost of recovering energy from biomass. In this study, we calculate for small- and large-project sizes, the relative cost of transportation by truck, rail, ship, and pipeline for three biomass feedstocks, by truck and pipeline for ethanol, and by transmission line for electrical power. Distance fixed costs (loading and unloading) and distance variable costs (transport, including power losses during transmission), are calculated for each biomass type and mode of transportation. Costs are normalized to a common basis of a giga Joules of biomass. The relative cost of moving products vs feedstock is an approximate measure of the incentive for location of biomass processing at the source of biomass, rather than at the point of ultimate consumption of produced energy. In general, the cost of transporting biomass is more than the cost of transporting its energy products. The gap in cost for transporting biomass vs power is significantly higher than the incremental cost of building and operating a power plant remote from a transmission grid. The cost of power transmission and ethanol transport by pipeline is highly dependent on scale of project. Transport of ethanol by truck has a lower cost than by pipeline up to capacities of 1800 t/d. The high cost of transshipment to a ship precludes shipping from being an economical mode of transport for distances less than 800 km (woodchips) and 1500 km (baled agricultural residues).
Transport aérien longue distance des brûlés graves: revue de la littérature et application pratique
Leclerc, T.; Hoffmann, C.; Forsans, E.; Cirodde, A.; Boutonnet, M.; Jault, P.; Tourtier, J.-P.; Bargues, L.; Donat, N.
2015-01-01
Summary Les brûlés graves nécessitent une prise en charge multidisciplinaire dans des centres hautement spécialisés. La rareté de ces centres impose souvent le transport aérien médicalisé longue distance. Cependant, il y a peu de données publiées sur ces transferts. Dans cette mise au point, pour optimiser la prise en charge des brûlés dès qu’un transport aérien est décidé ou même seulement envisagé, nous proposons d’extraire de cette littérature limitée des principes simples s’appuyant aussi sur l’expérience pratique du Service de Santé des Armées françaises. Nous décrivons d’abord comment les contraintes aéronautiques peuvent affecter le transport de brûlés graves à bord d’aéronefs. Nous abordons ensuite la régulation de ces missions, en analysant les risques associés au transport aérien des brûlés graves et leurs implications sur les indications, la chronologie et les modalités du transport. Enfin, nous développons la conduite de la mission, comprenant la préparation du matériel et des consommables avant le vol, l’évaluation et la mise en condition du patient avant l’embarquement, et la poursuite de la prise en charge en vol. PMID:26668564
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Distance requirement for employee sleeping... OF SERVICE OF RAILROAD EMPLOYEES; RECORDKEEPING AND REPORTING; SLEEPING QUARTERS Construction of Railroad-Provided Sleeping Quarters § 228.101 Distance requirement for employee sleeping quarters...
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Distance requirement for employee sleeping... OF SERVICE OF RAILROAD EMPLOYEES; RECORDKEEPING AND REPORTING; SLEEPING QUARTERS Construction of Railroad-Provided Sleeping Quarters § 228.101 Distance requirement for employee sleeping quarters...
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Distance requirement for employee sleeping... OF SERVICE OF RAILROAD EMPLOYEES; RECORDKEEPING AND REPORTING; SLEEPING QUARTERS Construction of Railroad-Provided Sleeping Quarters § 228.101 Distance requirement for employee sleeping quarters...
A comparison between using distance sensors for measuring the pantograph vertically movement
NASA Astrophysics Data System (ADS)
Rob, R.; Panoiu, C.; Rusu-Anghel, S.; Panoiu, M.
2018-01-01
In railway transportation the most important problem to solve consists in assuring the safety traffic of people and freight. In this scope some of the geometrical parameters regarding the contact line must be measured. One of this parameter is the pantograph vertically movement, so it must use distance sensors. Present paper studies the performance of two kinds of distance sensors, an ultrasonic distance sensor and an infrared sensor. The performances are studied from the point of view of error distance measurement and the possibility of using a real time acquisition system. The researches were made on a laboratory model for the pantograph realized at the scale 1:2.
David-Schwartz, Rakefet; Runo, Steven; Townsley, Brad; Machuka, Jesse; Sinha, Neelima
2008-01-01
It has been shown that the parasitic plant dodder (Cuscuta pentagona) establishes a continuous vascular system through which water and nutrients are drawn. Along with solutes, viruses and proteins, mRNA transcripts are transported from the host to the parasite. The path of the transcripts and their stability in the parasite have yet to be revealed. To discover the route of mRNA transportation, the in situ reverse transcriptase-polymerase chain reaction (RT-PCR) technique was used to locally amplify host transcript within parasitic tissue. The stability of host mRNA molecules was also checked by monitoring specific transcripts along the growing dodder thread. Four mRNAs, alpha and beta subunits of PYROPHOSPHATE (PPi)-DEPENDENT PHOSPHOFRUCTOKINASE (LePFP), the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), and GIBBERELLIC ACID INSENSITIVE (LeGAI), were found to move from host (tomato (Solanum lycopersicum)) to dodder. LePFP mRNA was localized to the dodder parenchyma cells and to the phloem. LePFP transcripts were found in the growing dodder stem up to 30 cm from the tomato-dodder connection. These results suggest that mRNA molecules are transferred from host to parasite via symplastic connections between parenchyma cells, move towards the phloem, and are stable for a long distance in the parasite. This may allow developmental coordination between the parasite and its host.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hwang, H.-L.; Rollow, J.
2000-05-01
The 1995 American Travel Survey (ATS) collected information from approximately 80,000 U.S. households about their long distance travel (one-way trips of 100 miles or more) during the year of 1995. It is the most comprehensive survey of where, why, and how U.S. residents travel since 1977. ATS is a joint effort by the U.S. Department of Transportation (DOT) Bureau of Transportation Statistics (BTS) and the U.S. Department of Commerce Bureau of Census (Census); BTS provided the funding and supervision of the project, and Census selected the samples, conducted interviews, and processed the data. This report documents the technical support formore » the ATS provided by the Center for Transportation Analysis (CTA) in Oak Ridge National Laboratory (ORNL), which included the estimation of trip distances as well as data quality editing and checking of variables required for the distance calculations.« less
Minimum Wage Effects in the Longer Run
ERIC Educational Resources Information Center
Neumark, David; Nizalova, Olena
2007-01-01
Exposure to minimum wages at young ages could lead to adverse longer-run effects via decreased labor market experience and tenure, and diminished education and training, while beneficial longer-run effects could arise if minimum wages increase skill acquisition. Evidence suggests that as individuals reach their late 20s, they earn less the longer…
2009-09-01
19 4. Domestic Port to Transportation Analysis Zone Distances ...........19 5. Truck Travel Times...20 6. Rail Travel Times...............................................................................20 7. Rail and...commercial container transportation network. An import container begins travel in a foreign port, enters the U.S. via a domestic port and can either
Bio-oil transport by pipeline: a techno-economic assessment.
Pootakham, Thanyakarn; Kumar, Amit
2010-09-01
Bio-oil, produced by fast pyrolysis of biomass, has high energy density compared to 'as received' biomass. The study assesses and compares the cost of transportation ($/liter of bio-oil) of bio-oil by pipeline and truck. The fixed and variable cost components of transportation of bio-oil at a pipeline capacity of 560 m(3)/day and to a distance of 100 km are 0.0423$/m(3) and 0.1201$/m(3)/km, respectively. Pipeline transportation of bio-oil costs less than transportation by liquid tank truck (load capacity 30 m(3)) and super B-train trailer (load capacity 60 m(3)) above pipeline capacities of 1000 and 1700 m(3)/day, respectively. When transportation distance is greater than 100 km, bio-oil must be heated at booster stations. When transporting bio-oil by pipeline to a distance of 400 km, minimum pipeline capacities of 1150 and 2000 m(3)/day are required to compete economically with liquid tank trucks and super B-train tank trailers, respectively. Copyright 2010 Elsevier Ltd. All rights reserved.
Hong, Jian; Wang, Wei-Bing; Zhou, Xue-Ping; Hu, Dong-Wei
2006-06-01
The alteration of ultrastructure in Pisum sativum and Vicia faba leaf cells infected with B935 isolate of BBWV 2 were investigated by electron microscopy, immunogold-labeling technique. The results showed that the membranous proliferation, virus-formed crystals and tubular structures were found in leaf cells of two hosts. At early stages of infection, the tubules containing virus-like particles associate with plasmodesmata in mesophyll cell. Immunogold particles anti-BBWV 2 were localized to the plasmodesmata modified by tubules passing through them. The membranous proliferation and virus-formed tubules were also found in the parenchyma cells, companion cells and transfer cells of vascular bundle. Some virus-like particles located within sieve tube can be labeled immunogold particles anti-BBWV 2. These suggest that BBWV 2, similar CPMV, produce tubules extending into the plasmodesmata. Virions assembled in the cytoplasm are escorted to the tubular structures through interactions with their MP and are then transported to the adjacent cell. Many 160 nm in diameter virus-formed tubules in the cytoplasm, as a special aggregate, not directly relate to cell-to-cell movement; Intact virions are long-distance sustemic transported possibly through sieve elements.
Experimental observations of transport of picosecond laser generated electrons in a nail-like target
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pasley, J.; Wei, M.; Shipton, E.
2007-12-15
The transport of relativistic electrons, generated by the interaction of a high intensity (2x10{sup 20} W/cm{sup 2}) laser, has been studied in a nail-like target comprised of a 20 {mu}m diameter solid copper wire, coated with {approx}2 {mu}m of titanium, with an 80 {mu}m diameter hemispherical termination. A {approx}500 fs, {approx}200 J pulse of 1.053 {mu}m laser light produced by the Titan Laser at Lawrence Livermore National Laboratory was focused to a {approx}20 {mu}m diameter spot centered on the flat face of the hemisphere. K{sub {alpha}} fluorescence from the Cu and Ti regions was imaged together with extreme ultraviolet (XUV)more » emission at 68 and 256 eV. Results showed a quasiexponential decline in K{sub {alpha}} emission along the wire over a distance of a few hundred microns from the laser focus, consistent with bulk Ohmic inhibition of the relativistic electron transport. Weaker K{sub {alpha}} and XUV emission on a longer scale length showed limb brightening suggesting a transition to enhanced transport at the surface of the wire.« less
NASA Technical Reports Server (NTRS)
Bugby, D. C.; Farmer, J. T.; Stouffer, C. J.
2013-01-01
This paper describes the development and testing of a scalable thermal control architecture for instruments, subsystems, or systems that must operate in severe space environments with wide variations in sink temperature. The architecture is comprised by linking one or more hot-side variable conductance heat pipes (VCHPs) in series with one or more cold-side loop heat pipes (LHPs). The VCHPs provide wide area heat acquisition, limited distance thermal transport, modest against gravity pumping, concentrated LHP startup heating, and high switching ratio variable conductance operation. The LHPs provide localized heat acquisition, long distance thermal transport, significant against gravity pumping, and high switching ratio variable conductance operation. Combining two variable conductance devices in series ensures very high switching ratio isolation from severe environments like the Earth's moon, where each lunar day spans 15 Earth days (270 K sink, with a surface-shielded/space viewing radiator) and each lunar night spans 15 Earth days (80-100 K radiative sink, depending on location). The single VCHP-single LHP system described herein was developed to maintain thermal control of International Lunar Network (ILN) anchor node lander electronics, but it is also applicable to other variable heat rejection space missions in severe environments. The LHPVCHP system utilizes a stainless steel wire mesh wick ammonia VCHP, a Teflon wick propylene LHP, a pair of one-third square meter high ? radiators (one capillary-pumped horizontal radiator and a second gravity-fed vertical radiator), a half-meter of transport distance, and a wick-bearing co-located flow regulator (CLFR) to allow operation with a hot (deactivated) radiator. The VCHP was designed with a small reservoir formed by extending the length of its stainless steel heat pipe tubing. The system was able to provide end-to-end switching ratios of 300-500 during thermal vacuum testing at ATK, including 3-5 W/K ON conductance
Code of Federal Regulations, 2010 CFR
2010-10-01
... restrictive block conditions stopping distance in advance. 236.502 Section 236.502 Transportation Other... Cab Signal Systems Standards § 236.502 Automatic brake application, initiation by restrictive block... initiate an automatic brake application at least stopping distance from the entrance to a block, wherein...
Colloid transport in dual-permeability media
USDA-ARS?s Scientific Manuscript database
It has been widely reported that colloids can travel faster and over longer distances in natural structured porous media than in uniform structureless media used in laboratory studies. The presence of preferential pathways for colloids in the subsurface environment is of concern because of the incre...
Pulse EPR distance measurements to study multimers and multimerisation
NASA Astrophysics Data System (ADS)
Ackermann, Katrin; Bode, Bela E.
2018-06-01
Pulse dipolar electron paramagnetic resonance (PD-EPR) has become a powerful tool for structural biology determining distances on the nanometre scale. Recent advances in hardware, methodology, and data analysis have widened the scope to complex biological systems. PD-EPR can be applied to systems containing lowly populated conformers or displaying large intrinsic flexibility, making them all but intractable for cryo-electron microscopy and crystallography. Membrane protein applications are of particular interest due to the intrinsic difficulties for obtaining high-resolution structures of all relevant conformations. Many drug targets involved in critical cell functions are multimeric channels or transporters. Here, common approaches for introducing spin labels for PD-EPR cause the presence of more than two electron spins per multimeric complex. This requires careful experimental design to overcome detrimental multi-spin effects and to secure sufficient distance resolution in presence of multiple distances. In addition to obtaining mere distances, PD-EPR can also provide information on multimerisation degrees allowing to study binding equilibria and to determine dissociation constants.
Smith, Matthew Lee; Prohaska, Thomas R; MacLeod, Kara E; Ory, Marcia G; Eisenstein, Amy R; Ragland, David R; Irmiter, Cheryl; Towne, Samuel D; Satariano, William A
2017-02-10
Background : Older adults in rural areas have unique transportation barriers to accessing medical care, which include a lack of mass transit options and considerable distances to health-related services. This study contrasts non-emergency medical transportation (NEMT) service utilization patterns and associated costs for Medicaid middle-aged and older adults in rural versus urban areas. Methods : Data were analyzed from 39,194 NEMT users of LogistiCare-brokered services in Delaware residing in rural (68.3%) and urban (30.9%) areas. Multivariable logistic analyses compared trip characteristics by rurality designation. Results : Rural (37.2%) and urban (41.2%) participants used services more frequently for dialysis than for any other medical concern. Older age and personal accompaniment were more common and wheel chair use was less common for rural trips. The mean cost per trip was greater for rural users (difference of $2910 per trip), which was attributed to the greater distance per trip in rural areas. Conclusions : Among a sample who were eligible for subsidized NEMT and who utilized this service, rural trips tended to be longer and, therefore, higher in cost. Over 50% of trips were made for dialysis highlighting the need to address prevention and, potentially, health service improvements for rural dialysis patients.
Smith, Matthew Lee; Prohaska, Thomas R.; MacLeod, Kara E.; Ory, Marcia G.; Eisenstein, Amy R.; Ragland, David R.; Irmiter, Cheryl; Towne, Samuel D.; Satariano, William A.
2017-01-01
Background: Older adults in rural areas have unique transportation barriers to accessing medical care, which include a lack of mass transit options and considerable distances to health-related services. This study contrasts non-emergency medical transportation (NEMT) service utilization patterns and associated costs for Medicaid middle-aged and older adults in rural versus urban areas. Methods: Data were analyzed from 39,194 NEMT users of LogistiCare-brokered services in Delaware residing in rural (68.3%) and urban (30.9%) areas. Multivariable logistic analyses compared trip characteristics by rurality designation. Results: Rural (37.2%) and urban (41.2%) participants used services more frequently for dialysis than for any other medical concern. Older age and personal accompaniment were more common and wheel chair use was less common for rural trips. The mean cost per trip was greater for rural users (difference of $2910 per trip), which was attributed to the greater distance per trip in rural areas. Conclusions: Among a sample who were eligible for subsidized NEMT and who utilized this service, rural trips tended to be longer and, therefore, higher in cost. Over 50% of trips were made for dialysis highlighting the need to address prevention and, potentially, health service improvements for rural dialysis patients. PMID:28208610
Passenger transport and CO 2 emissions: What does the French transport survey tell us?
NASA Astrophysics Data System (ADS)
Nicolas, Jean-Pierre; David, Damien
The aim of this article is to analyse CO 2 emissions caused by passenger transport in France: which socio-demographic groups travel, for what kinds of journey (local or long distance), how and why? Research focusing on the analysis of individual travel can improve the understanding of CO 2 emissions by identifying upstream socio-economic factors, and also enable a better assessment of the potential social impact of measures introduced to limit greenhouse gases due to transport. Calculations are based on the latest French national transport survey (1994). Distances covered and CO 2 emissions were estimated for each journey and for each surveyed individual. A socio-demographic characteristic typology was built and results were obtained through this analysis. If equity and accessibility issues are to be taken into account, planned policies cannot be of the same type if linked to mobility segments. An environmental tax system to limit CO 2 emission increases appears appropriate for long-distance trips. Results are more varied for local journeys, which are often more of a necessity. Nevertheless, income brackets, and measures concerning urban planning or the growth of new car fleets, seem more pertinent.
Barrett, E S; Hoeger, K M; Sathyanarayana, S; Abbott, D H; Redmon, J B; Nguyen, R H N; Swan, S H
2018-06-01
Polycystic ovary syndrome (PCOS) affects ~7% of reproductive age women. Although its etiology is unknown, in animals, excess prenatal testosterone (T) exposure induces PCOS-like phenotypes. While measuring fetal T in humans is infeasible, demonstrating in utero androgen exposure using a reliable newborn biomarker, anogenital distance (AGD), would provide evidence for a fetal origin of PCOS and potentially identify girls at risk. Using data from a pregnancy cohort (The Infant Development and Environment Study), we tested the novel hypothesis that infant girls born to women with PCOS have longer AGD, suggesting higher fetal T exposure, than girls born to women without PCOS. During pregnancy, women reported whether they ever had a PCOS diagnosis. After birth, infant girls underwent two AGD measurements: anofourchette distance (AGD-AF) and anoclitoral distance (AGD-AC). We fit adjusted linear regression models to examine the association between maternal PCOS and girls' AGD. In total, 300 mother-daughter dyads had complete data and 23 mothers reported PCOS. AGD was longer in the daughters of women with a PCOS diagnosis compared with daughters of women with no diagnosis (AGD-AF: β=1.21, P=0.05; AGD-AC: β=1.05, P=0.18). Results were stronger in analyses limited to term births (AGD-AF: β=1.65, P=0.02; AGD-AC: β=1.43, P=0.09). Our study is the first to examine AGD in offspring of women with PCOS. Our results are consistent with findings that women with PCOS have longer AGD and suggest that during PCOS pregnancies, daughters may experience elevated T exposure. Identifying the underlying causes of PCOS may facilitate early identification and intervention for those at risk.
Transport logistics in pollen tubes.
Chebli, Youssef; Kroeger, Jens; Geitmann, Anja
2013-07-01
Cellular organelles move within the cellular volume and the effect of the resulting drag forces on the liquid causes bulk movement in the cytosol. The movement of both organelles and cytosol leads to an overall motion pattern called cytoplasmic streaming or cyclosis. This streaming enables the active and passive transport of molecules and organelles between cellular compartments. Furthermore, the fusion and budding of vesicles with and from the plasma membrane (exo/endocytosis) allow for transport of material between the inside and the outside of the cell. In the pollen tube, cytoplasmic streaming and exo/endocytosis are very active and fulfill several different functions. In this review, we focus on the logistics of intracellular motion and transport processes as well as their biophysical underpinnings. We discuss various modeling attempts that have been performed to understand both long-distance shuttling and short-distance targeting of organelles. We show how the combination of mechanical and mathematical modeling with cell biological approaches has contributed to our understanding of intracellular transport logistics.
Chen, Chun-Fu; Huang, Kuo-Chen
2016-04-01
This study investigated the effects of target distance (30, 35, and 40 cm) and the color of background lighting (red, green, blue, and yellow) on the duration of movements made by participants with low vision, myopia, and normal vision while performing a reaching task; 48 students (21 women, 27 men; M age = 21.8 year, SD = 2.4) participated in the study. Participants reached for a target (a white LED light) whose vertical position varied randomly across trials, ranging in distance from 30 to 40 cm. Movement time was analyzed using a 3 (participant group) × [4 (color of background lighting) × 3 (movement distance)] mixed-design ANOVA model. Results indicated longer times for completing a reaching movement when: participants belonged to the low vision group; the target distance between the starting position and the target position was longer (40 cm); and the reaching movement occurred in the red-background lighting condition. These results are particularly relevant for situations in which a user is required to respond to a signal by reaching toward a button or an icon. © The Author(s) 2016.
NASA Astrophysics Data System (ADS)
Philip, S.; Martin, R. V.; Keller, C. A.
2015-11-01
Chemical transport models involve considerable computational expense. Fine temporal resolution offers accuracy at the expense of computation time. Assessment is needed of the sensitivity of simulation accuracy to the duration of chemical and transport operators. We conduct a series of simulations with the GEOS-Chem chemical transport model at different temporal and spatial resolutions to examine the sensitivity of simulated atmospheric composition to temporal resolution. Subsequently, we compare the tracers simulated with operator durations from 10 to 60 min as typically used by global chemical transport models, and identify the timesteps that optimize both computational expense and simulation accuracy. We found that longer transport timesteps increase concentrations of emitted species such as nitrogen oxides and carbon monoxide since a more homogeneous distribution reduces loss through chemical reactions and dry deposition. The increased concentrations of ozone precursors increase ozone production at longer transport timesteps. Longer chemical timesteps decrease sulfate and ammonium but increase nitrate due to feedbacks with in-cloud sulfur dioxide oxidation and aerosol thermodynamics. The simulation duration decreases by an order of magnitude from fine (5 min) to coarse (60 min) temporal resolution. We assess the change in simulation accuracy with resolution by comparing the root mean square difference in ground-level concentrations of nitrogen oxides, ozone, carbon monoxide and secondary inorganic aerosols with a finer temporal or spatial resolution taken as truth. Simulation error for these species increases by more than a factor of 5 from the shortest (5 min) to longest (60 min) temporal resolution. Chemical timesteps twice that of the transport timestep offer more simulation accuracy per unit computation. However, simulation error from coarser spatial resolution generally exceeds that from longer timesteps; e.g. degrading from 2° × 2.5° to 4° × 5
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lasuik, J.; Shalchi, A., E-mail: andreasm4@yahoo.com
Recently, a new theory for the transport of energetic particles across a mean magnetic field was presented. Compared to other nonlinear theories the new approach has the advantage that it provides a full time-dependent description of the transport. Furthermore, a diffusion approximation is no longer part of that theory. The purpose of this paper is to combine this new approach with a time-dependent model for parallel transport and different turbulence configurations in order to explore the parameter regimes for which we get ballistic transport, compound subdiffusion, and normal Markovian diffusion.
The Effects of Distance and Intervening Obstacles on Visual Inference in Blind and Sighted Children.
ERIC Educational Resources Information Center
Bigelow, Ann E.
1991-01-01
Blind and visually impaired children, and children with normal sight, were asked whether an observer could see a toy from varying distances under conditions in which obstacles did or did not intervene between the toy and the observer. Blind children took longer than other children to master the task. (BC)
Tsuchiya, Takeru; Hobo, Seiji; Endo, Yoshiro; Narita, Shoichi; Sakamoto, Koji
2012-07-01
To evaluate effects of a single dose of enrofloxacin (5 mg/kg, IV) on body temperature and tracheobronchial neutrophil count in healthy Thoroughbreds premedicated with interferon-α and undergoing long-distance transportation. 32 healthy Thoroughbreds. All horses received interferon-α (0.5 U/kg, sublingually, q 24 h) as an immunologic stimulant for 2 days before transportation and on the day of transportation. Horses were randomly assigned to receive enrofloxacin (5 mg/kg, IV, once; enrofloxacin group) or saline (0.9% NaCl) solution (50 mL, IV, once; control group) ≤ 1 hour before being transported 1,210 km via commercial vans (duration, approx 26 hours). Before and after transportation, clinical examination, measurement of temperature per rectum, and hematologic analysis were performed for all horses; a tracheobronchial aspirate was collected for neutrophil quantification in 12 horses (6/group). Horses received antimicrobial treatment after transportation if deemed necessary by the attending clinician. No adverse effects were associated with treatment. After transportation, WBC count and serum amyloid A concentration in peripheral blood samples and neutrophil counts in tracheobronchial aspirates were significantly lower in horses of the enrofloxacin group than in untreated control horses. Fever (rectal temperature, ≥ 38.5°C) after transportation was detected in 3 of 16 enrofloxacin group horses and 9 of 16 control horses; additional antimicrobial treatment was required in 2 horses in the enrofloxacin group and 7 horses in the control group. In horses premedicated with interferon-α, enrofloxacin appeared to provide better protection against fever and lower respiratory tract inflammation than did saline solution.
Kinetic Effects Of Increased Proton Transfer Distance On Proton-Coupled Oxidations Of Phenol-Amines
Rhile, Ian J.
2011-01-01
To test the effect of varying the proton donor-acceptor distance in proton-coupled electron transfer (PCET) reactions, the oxidation of a bicyclic amino-indanol (2) is compared with that of a closely related phenol with an ortho CPh2NH2 substituent (1). Spectroscopic, structural, thermochemical and computational studies show that the two amino-phenols are very similar, except that the O⋯N distance (dON) is >0.1 Å longer in 2 than in 1. The difference in dON is 0.13 ± 0.03 Å from X-ray crystallography and 0.165 Å from DFT calculations. Oxidations of these phenols by outer-sphere oxidants yield distonic radical cations •OAr–NH3+ by concerted proton-electron transfer (CPET). Simple tunneling and classical kinetic models both predict that the longer donor-acceptor distance in 2 should lead to slower reactions, by ca. two orders of magnitude, as well as larger H/D kinetic isotope effects (KIEs). However, kinetic studies show that the compound with the longer proton-transfer distance, 2, exhibits smaller KIEs and has rate constants that are quite close to those of 1. For example, the oxidation of 2 by the triarylamminium radical cation N(C6H4OMe)3•+ (3a+) occurs at (1.4 ± 0.1) × 104 M-1 s-1, only a factor of two slower than the closely related reaction of 1 with N(C6H4OMe)2(C6H4Br)•+ (3b+). This difference in rate constants is well accounted for by the slightly different free energies of reaction: ΔG°(2 + 3a+) = +0.078 V vs. ΔG°(1 + 3b+) = +0.04 V. The two phenol-amines do display some subtle kinetic differences: for instance, compound 2 has a shallower dependence of CPET rate constants on driving force (Brønsted α, Δln(k)/Δln(Keq)). These results show that the simple tunneling model is not a good predictor of the effect of proton donor-acceptor distance on concerted-electron transfer reactions involving strongly hydrogen-bonded systems. Computational analysis of the observed similarity of the two phenols emphasizes the importance of the highly
Vogt, Deborah R; Murrell, David J; Stoll, Peter
2010-01-01
Plants stand still and interact with their immediate neighbors. Theory has shown that the distances over which these interactions occur may have important consequences for population and community dynamics. In particular, if intraspecific competition occurs over longer distances than interspecific competition (heteromyopia), coexistence can be promoted. We examined how intraspecific and interspecific competition scales with neighbor distance in a target-neighbor greenhouse competition experiment. Individuals from co-occurring forbs from calcareous grasslands were grown in isolation and with single conspecific or heterospecific neighbors at distances of 5, 10, or 15 cm (Plantago lanceolata vs. Plantago media and Hieracium pilosella vs. Prunella grandiflora). Neighbor effects were strong and declined with distance. Interaction distances varied greatly within and between species, but we found no evidence for heteromyopia. Instead, neighbor identity effects were mostly explained by relative size differences between target and neighbor. We found a complex interaction between final neighbor size and identity such that neighbor identity may become important only as the neighbor becomes very large compared with the target individual. Our results suggest that species-specific size differences between neighboring individuals determine both the strength of competitive interactions and the distance over which these interactions occur.
Fazio, E.; Medica, P.; Cravana, C.; Ferlazzo, and A.
2016-01-01
Aim: The changes of the hypothalamic pituitary adrenal (HPA) axis response to a long distance transportation results in increase of adrenocorticotropic hormone (ACTH) and cortisol levels. The purpose of the study was to quantify the level of short-term road transport stress on circulating ACTH and cortisol concentrations, related to the effect of previous handling and transport experience of horses. Materials and Methods: The study was performed on 56 healthy horses after short-term road transport of 30 km. The horses were divided into four groups, Groups A, B, C, and D, with respect to the handling quality: Good (Groups A and B), bad (Group D), and minimal handling (Group C) conditions. According to the previous transport, experience horses were divided as follows: Horses of Groups A and D had been experienced long-distance transportation before; horses of Groups B and C had been limited experience of transportation. Results: One-way RM-ANOVA showed significant effects of transport on ACTH changes in Groups B and C and on cortisol changes in both Groups A and B. Groups A and B showed lower baseline ACTH and cortisol values than Groups C and D; Groups A and B showed lower post-transport ACTH values than Groups C and D. Groups A, B, and C showed lower post-transport cortisol values than Group D. Only Groups A and B horses have shown an adequate capacity of stress response to transportation. Conclusion: The previous transport experience and quality of handling could influence the HPA axis physiological responses of horses after short-term road transport. PMID:27651674
Transport of Indirect Excitons in High Magnetic Fields
NASA Astrophysics Data System (ADS)
Dorow, C. J.; Kuznetsova, Y. Y.; Calman, E. V.; Butov, L. V.; Wilkes, J.; Campman, K. L.; Gossard, A. C.
Spatially- and spectrally-resolved photoluminescence measurements of indirect excitons in high magnetic fields are presented. The high magnetic field regime for excitons is realized when the cyclotron splitting compares to the exciton binding energy. Due to small mass and binding energy, the high magnetic field regime for excitons is achievable in lab, requiring a few Tesla. Long indirect exciton lifetimes allow large exciton transport distances before recombination, giving an opportunity to study transport and relaxation kinetics of indirect magnetoexcitons via optical imaging. Indirect excitons in several Landau level states are realized. 0e -0h indirect magnetoexcitons (formed from electrons and holes at zeroth Landau levels) travel over large distances and form an emission ring around the excitation spot. In contrast, the 1e -1h and 2e -2h states do not exhibit long transport distances, and the spatial profiles of the emission closely follow the laser excitation. The 0e -0h indirect magnetoexciton transport distance reduces with increasing magnetic field. Accompanying theoretical work explains these effects in terms of magnetoexciton energy relaxation and effective mass enhancement. Supported by NSF Grant No. 1407277. J.W. was supported by the EPSRC (Grant EP/L022990/1). C.J.D. was supported by the NSF Graduate Research Fellowship Program under Grant No. DGE-1144086.
Distance still matters. The hard reality of global expansion.
Ghemawat, P
2001-09-01
Companies routinely overestimate the attractiveness of foreign markets. Dazzled by the sheer size of untapped markets, they lose sight of the difficulties of pioneering new, often very different territories. The problem is rooted in the analytic tools (the most prominent being country portfolio analysis, or CPA) that managers use to judge international investments. By focusing on national wealth, consumer income, and people's propensity to consume, CPA emphasizes potential sales, ignoring the costs and risks of doing business in a new market. Most of these costs and risks result from the barriers created by distance. "Distance," however, does not refer only to geography; its other dimensions can make foreign markets considerably more or less attractive. The CAGE framework of distance presented here considers four attributes: cultural distance (religious beliefs, race, social norms, and language that are different for the target country and the country of the company considering expansion); administrative or political distance (colony-colonizer links, common currency, and trade arrangements); geographic distance (the physical distance between the two countries, the size of the target country, access to waterways and the ocean, internal topography, and transportation and communications infrastructures); and economic distance (disparities in the two countries' wealth or consumer income and variations in the cost and quality of financial and other resources). This framework can help to identify the ways in which potential markets may be distant from existing ones. The article explores how (and by how much) various types of distance can affect different types of industries and shows how dramatically an explicit consideration of distance can change a company's picture of its strategic options.
The transport of nuclear power plant components. [via airships
NASA Technical Reports Server (NTRS)
Keating, S. J., Jr.
1975-01-01
The problems of transporting nuclear power plant components to landlocked sites where the usual mode of transport by barge cannot be used are considered. Existing methods of ground-based overland transport are discussed and their costs presented. Components are described and traffic density projections made to the year 2000. Plots of units transported versus distance transported are provided for units booked in 1973 and booked and proposed in 1974. It is shown that, for these cases, overland transport requirements for the industry will be over 5,000,000 ton-miles/year while a projection based on increasing energy demands shows that this figure will increase significantly by the year 2000. The payload size, distances, and costs of existing overland modes are significant enough to consider development of a lighter than air (LTA) mode for transporting NSSS components.
Ordóñez-Gómez, José D; Santillán-Doherty, Ana M; Fischer, Julia; Hammerschmidt, Kurt
2018-04-01
Due to several factors such as ecological conditions, group size, and social organization, primates frequently spend time out of visual contact with individuals of their own group. Through the use of long-distance vocalizations, often termed "contact calls," primates are able to maintain contact with out-of-sight individuals. Contact calls have been shown to be individually distinct, and reverberation and attenuation provide information about caller distance. It is less clear, however, whether callers actively change the structure of contact calls depending on the distance to the presumed listeners. We studied this question in spider monkeys (Ateles geoffroyi), a species with complex spatial dynamics (fission-fusion society) that produces highly frequency modulated contact calls, denominated "whinnies." We determined the acoustic characteristics of 566 whinnies recorded from 35 free-ranging spider monkeys that belong to a community located in Mexico, and used cluster analyses, discriminant function analyses, and generalized linear mixed models to assess if they varied in relation to the presumed distance to the listener. Whinnies could be grouped into five subtypes. Since the lowest frequency subtype was mainly produced by spider monkeys that exchanged whinnies at longer distances, and lower frequency calls propagate across longer distances, our results suggest that whinnies vary in order to enhance vocal contact between individuals separated by different distances. Our results also revealed that whinnies convey potential information about caller immediate behaviors and corroborated that these calls are individually distinct. Overall, our results suggest that whinny acoustic variation facilitates the maintenance of vocal contact between individuals living in a society with complex spatial dynamics. © 2018 Wiley Periodicals, Inc.
Gomez-Gonzalez, Miguel A; Villalobos, Mario; Marco, Jose Francisco; Garcia-Guinea, Javier; Bolea, Eduardo; Laborda, Francisco; Garrido, Fernando
2018-04-01
Mine wastes from abandoned exploitations are sources of high concentrations of hazardous metal(oid)s. Although these contaminants can be attenuated by sorbing to secondary minerals, in this work we identified a mechanism for long-distance dispersion of arsenic and metals through their association to mobile colloids. We characterize the colloids and their sorbed contaminants using spectrometric and physicochemical fractionation techniques. Mechanical action through erosion may release and transport high concentrations of colloid-associated metal(oid)s towards nearby stream waters, promoting their dispersion from the contamination source. Poorly crystalline ferrihydrite acts as the principal As-sorbing mineral, but in this study we find that this nanomineral does not mobilize As independently, rather, it is transported as surface coatings bound to mineral particles, perhaps through electrostatic biding interactions due to opposing surface charges at acidic to circumneutral pH values. This association is very stable and effective in carrying along metal(oid)s in concentrations above regulatory levels. The unlimited source of toxic elements in mine residues causes ongoing, decades-long mobilization of toxic elements into stream waters. The ferrihydrite-clay colloidal composites and their high mobility limit the attenuating role that iron oxides alone show through adsorption of metal(oid)s and their immobilization in situ. This may have important implications for the potential bioavailability of these contaminants, as well as for the use of this water for human consumption. Copyright © 2018 Elsevier Ltd. All rights reserved.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Separation distance requirements for storage of hydrogen peroxide, hydrazine, and liquid hydrogen and any incompatible energetic liquids stored within an intraline distance. 420.66 Section 420.66 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Separation distance requirements for storage of hydrogen peroxide, hydrazine, and liquid hydrogen and any incompatible energetic liquids stored within an intraline distance. 420.66 Section 420.66 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION...
Effect of airplane transport of donor livers on post-liver transplantation survival
Huang, Yi; MacQuillan, Gerry; Adams, Leon A; Garas, George; Collins, Megan; Nwaba, Albert; Mou, Linjun; Bulsara, Max K; Delriviere, Luc; Jeffrey, Gary P
2016-01-01
AIM To evaluate the effect of long haul airplane transport of donor livers on post-transplant outcomes. METHODS A retrospective cohort study of patients who received a liver transplantation was performed in Perth, Australia from 1992 to 2012. Donor and recipient characteristics information were extracted from Western Australian liver transplantation service database. Patients were followed up for a mean of six years. Patient and graft survival were evaluated and compared between patients who received a local donor liver and those who received an airplane transported donor liver. Predictors of survival were determined by univariate and multivariate analysis using cox regression. RESULTS One hundred and ninety-three patients received a local donor liver and 93 patients received an airplane transported donor liver. Airplane transported livers had a significantly lower alanine transaminase (mean: 45 U/L vs 84 U/L, P = 0.035), higher donor risk index (mean: 1.88 vs 1.42, P < 0.001) and longer cold ischemic time (CIT) (mean: 10.1 h vs 6.4 h, P < 0.001). There was a weak correlation between CIT and transport distance (r2 = 0.29, P < 0.001). Mean follow up was six years and 93 patients had graft failure. Multivariate analysis found only airplane transport retained significance for graft loss (HR = 1.92, 95%CI: 1.16-3.17). One year graft survival was 0.88 for those with a local liver and was 0.71 for those with an airplane transported liver. One year graft loss was due to primary graft non-function or associated with preservation injury in 20.8% of recipients of an airplane transported liver compared with 4.6% in those with a local liver (P = 0.027). CONCLUSION Airplane transport of donor livers was independently associated with reduced graft survival following liver transplantation. PMID:27895402
Effect of airplane transport of donor livers on post-liver transplantation survival.
Huang, Yi; MacQuillan, Gerry; Adams, Leon A; Garas, George; Collins, Megan; Nwaba, Albert; Mou, Linjun; Bulsara, Max K; Delriviere, Luc; Jeffrey, Gary P
2016-11-07
To evaluate the effect of long haul airplane transport of donor livers on post-transplant outcomes. A retrospective cohort study of patients who received a liver transplantation was performed in Perth, Australia from 1992 to 2012. Donor and recipient characteristics information were extracted from Western Australian liver transplantation service database. Patients were followed up for a mean of six years. Patient and graft survival were evaluated and compared between patients who received a local donor liver and those who received an airplane transported donor liver. Predictors of survival were determined by univariate and multivariate analysis using cox regression. One hundred and ninety-three patients received a local donor liver and 93 patients received an airplane transported donor liver. Airplane transported livers had a significantly lower alanine transaminase (mean: 45 U/L vs 84 U/L, P = 0.035), higher donor risk index (mean: 1.88 vs 1.42, P < 0.001) and longer cold ischemic time (CIT) (mean: 10.1 h vs 6.4 h, P < 0.001). There was a weak correlation between CIT and transport distance ( r 2 = 0.29, P < 0.001). Mean follow up was six years and 93 patients had graft failure. Multivariate analysis found only airplane transport retained significance for graft loss (HR = 1.92, 95%CI: 1.16-3.17). One year graft survival was 0.88 for those with a local liver and was 0.71 for those with an airplane transported liver. One year graft loss was due to primary graft non-function or associated with preservation injury in 20.8% of recipients of an airplane transported liver compared with 4.6% in those with a local liver ( P = 0.027). Airplane transport of donor livers was independently associated with reduced graft survival following liver transplantation.
Evaluation of pre-hospital transport time of stroke patients to thrombolytic treatment.
Simonsen, Sofie Amalie; Andresen, Morten; Michelsen, Lene; Viereck, Søren; Lippert, Freddy K; Iversen, Helle Klingenberg
2014-11-13
Effective treatment of stroke is time dependent. Pre-hospital management is an important link in reducing the time from occurrence of stroke symptoms to effective treatment. The aim of this study was to evaluate time used by emergency medical services (EMS) for stroke patients during a five-year period in order to identify potential delays and evaluate the reorganization of EMS in Copenhagen in 2009. We performed a retrospective analysis of ambulance records from stroke patients suitable for thrombolysis from 1 January 2006 to 7 July 2011. We noted response time from dispatch of the ambulance to arrival at the scene, on-scene time and transport time to the hospital-in total, alarm-to-door time. In addition, we noted baseline characteristics. We reviewed 481 records (58% male, median age 66 years). The median (IQR) alarm-to-door time in minutes was 41 (33-52), of which 18 (12-24) minutes were spent on scene. Response time was reduced from the period before to the period after reorganization (7 vs. 5 minutes, p <0.001). In a linear multiple regression model, higher patient age and longer distance to the hospital correlated with significantly longer transportation time (p <0.001). This study shows an unchanged alarm-to-door time of 41 minutes over a five-year period. Response time, but not total alarm-to-door time, was reduced during the five years. On-scene time constituted nearly half of the total alarm-to-door time and is thus a point of focus for improvement.
2012-03-22
new paradigm. States are no longer the primary actors in conflicts. Non-state actors, including warlords, tribes, guerillas/insurgent groups ...narco-terrorists and religious extremist groups are responsible for the preeminence of intrastate conflicts today. With very few exceptions, countries...work of definitive research” and more of a “…thematic discussion rather than a definitive history …”4 As such, the book lacks any references to
Independent coding of absolute duration and distance magnitudes in the prefrontal cortex
Marcos, Encarni; Tsujimoto, Satoshi
2016-01-01
The estimation of space and time can interfere with each other, and neuroimaging studies have shown overlapping activation in the parietal and prefrontal cortical areas. We used duration and distance discrimination tasks to determine whether space and time share resources in prefrontal cortex (PF) neurons. Monkeys were required to report which of two stimuli, a red circle or blue square, presented sequentially, were longer and farther, respectively, in the duration and distance tasks. In a previous study, we showed that relative duration and distance are coded by different populations of neurons and that the only common representation is related to goal coding. Here, we examined the coding of absolute duration and distance. Our results support a model of independent coding of absolute duration and distance metrics by demonstrating that not only relative magnitude but also absolute magnitude are independently coded in the PF. NEW & NOTEWORTHY Human behavioral studies have shown that spatial and duration judgments can interfere with each other. We investigated the neural representation of such magnitudes in the prefrontal cortex. We found that the two magnitudes are independently coded by prefrontal neurons. We suggest that the interference among magnitude judgments might depend on the goal rather than the perceptual resource sharing. PMID:27760814
Ringler, Eva; Pašukonis, Andrius; Hödl, Walter; Ringler, Max
2013-11-09
Individuals should aim to adjust their parental behaviours in order to maximize the success of their offspring but minimize associated costs. Plasticity in parental care is well documented from various bird, mammal and fish species, whereas amphibians were traditionally assumed as being highly instinct-bound. Therefore, little is known about 'higher' cognitive abilities of amphibians, such as strategic planning and behavioural flexibility. Dendrobatid frogs have evolved a remarkable diversity of parental behaviours. The most noticeable of these behaviours is tadpole transport, which is obligatory in almost all species. Nonetheless, there is limited knowledge about spatial and temporal patterns of tadpole transport and the possible existence of behavioural plasticity on the individual level. In this study, we investigated correlates of tadpole transport behaviour in a natural population of the dendrobatid frog Allobates femoralis during five years. Tadpole transport was predominantly observed during morning hours. Although tadpoles were carried almost exclusively by males (N = 119), we also observed ten females performing this task. The parentage analysis revealed that in all cases females transported their own offspring. In contrast, four tadpole-carrying males were not the genetic fathers of the larvae they were transporting. The average clutch size of 20 eggs and our observation of an average of 8 tadpoles on the back of transporting individuals indicate that frogs do not carry entire clutches at once, and/or that they distribute their larvae across several water bodies. Contrary to the predictions from a hypothetical random search for deposition sites, the number of transported tadpoles was higher in males that travelled over longer distances. Our results suggest a strong selective pressure on males to shift the time invested in tadpole transport to periods of low intra-specific competition. The number of tadpoles on the back of the males significantly
Papadopoulou, Eleni; Vafeiadi, Marina; Agramunt, Silvia; Basagaña, Xavier; Mathianaki, Kleopatra; Karakosta, Polykseni; Spanaki, Arianna; Koutis, Antonis; Chatzi, Leda; Vrijheid, Martine; Kogevinas, Manolis
2013-01-01
Anogenital distance has been associated with prenatal exposure to chemicals with anti-androgenic effects. There are limited data in humans concerning descriptive patterns, predictors, and the reliability of measurement of anogenital distances. We examined anogenital distance measurements and their predictors in males and females and further estimated the reliability of these measurements. Anogenital distances were measured in repeated time periods among 352 newborns and 732 young children in two cohorts, one in Crete, Greece and one in Barcelona, Spain. Mixed effect models were used to estimate the between-children, between- and within-examiners variance, as well as the reliability coefficients. Genitalia distances were longer in males than in females. Anogenital distances in both sexes increased rapidly from birth to 12 months, while the additional increase during the second year was small. Birthweight was associated with an increase of 1.9 mm/kg [95% CI 0.1, 3.8] (CI, confidence interval) in the anogenital distance measured from the anus to anterior base of the penis in newborn males, 2.9 mm/kg [95% CI 1.8, 3.9] in anoclitoral distance and 1.0 mm/kg [95% CI 0.0, 2.0] in anofourchettal distance in newborn females, after adjustment for gestational age. In children, body weight was the main predictor of all genitalia measurements. Moreover, anogenital distances at birth were associated with the corresponding distances at early childhood. High reliability coefficients (>90%) were found for all anogenital distances measurements in males and females. Anogenital distances are strongly related to gestational age and birthweight and later, to growth. They track through early life and are highly reliable measures in both sexes. © 2012 Blackwell Publishing Ltd.
Mobile Resource Use in a Distance Learning Population: What Are They Really Doing on Those Devices?
ERIC Educational Resources Information Center
Gebb, Billie Anne; Young, Zach
2014-01-01
Mobile device use has been soaring in recent years in all user groups. Mobile learning is no longer an optional activity for academic institutions, but a necessary endeavor. Developing a curriculum around mobile learning is essential, particularly for distance-based, non-traditional students. Understanding how students use their mobile devices is…
Blomefield, T; Carpenter, J E; Vreysen, M J B
2011-06-01
The sterile insect technique (SIT) is a proven effective control tactic against lepidopteran pests when applied in an areawide integrated pest management program. The construction of insect mass-rearing facilities requires considerable investment and moth control strategies that include the use of sterile insects could be made more cost-effective through the importation of sterile moths produced in other production centers. For codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), this is an attractive option because mating studies have confirmed the absence of mating barriers between codling moth populations from geographically different areas. To assess the feasibility of long-distance transportation of codling moths, pupae and adult moths were transported in 2004 from Canada to South Africa in four shipments by using normal commercial transport routes. The total transport time remained below 67 h in three of the consignments, but it was 89 h in the fourth consignment. Temperature in the shipping boxes was fairly constant and remained between -0.61 and 0.16 degrees C for 76.8-85.7% of the time. The data presented indicate that transporting codling moths as adults and pupae from Canada to South Africa had little effect on moth emergence, longevity, and ability to mate, as assessed in the laboratory. These results provide support to the suggestion that the STT for codling moth in pome fruit production areas might be evaluated and implemented by the importation of irradiated moths from rearing facilities in a different country or hemisphere.
Buor, Daniel
2003-01-01
Although the distance factor has been identified as key in the utilization of health services in rural areas of developing countries, it has been analysed without recourse to related factors of travel time and transport cost. Also, the influence of distance on vulnerable groups in utilization has not been an object of survey by researchers. This paper addresses the impact of distance on utilization, and how distance compares with travel time and transport cost that are related to it in the utilization of health services in the Ahafo-Ano South (rural) district in Ghana. The study, a cross-sectional survey, also identifies the position of distance among other important factors of utilization. A sample of 400, drawn through systematic random technique, was used for the survey. Data were analysed using the regression model and some graphic techniques. The main instruments used in data collection were formal (face-by-face) interview and a questionnaire. The survey finds that distance is the most important factor that influences the utilization of health services in the Ahafo-Ano South district. Other key factors are income, service cost and education. The effect of travel time on utilization reflects that of distance and utilization. Recommendations to reduce distance coverage, improve formal education and reduce poverty have been made.
Fleet analysis of headway distance for autonomous driving.
Ivanco, Andrej
2017-12-01
Modern automobiles are going through a paradigm shift, where the driver may no longer be needed to drive the vehicle. As the self-driving vehicles are making their way to public roads the automakers have to ensure the naturalistic driving feel to gain drivers' confidence and accelerate adoption rates. This paper filters and analyzes a subset of radar data collected from SHRP2 with focus on characterizing the naturalistic headway distance with respect to the vehicle speed. The paper identifies naturalistic headway distance and compares it with the previous findings from the literature. A clear relation between time headway and speed was confirmed and quantified. A significant difference exists among individual drivers which supports a need to further refine the analysis. By understanding the relationship between human driving and their surroundings, the naturalistic driving behavior can be quantified and used to increase the adoption rates of autonomous driving. Dangerous and safety-compromising driving can be identified as well in order to avoid its replication in the control algorithms. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Separation distance requirements for handling incompatible energetic liquids that are co-located. 420.67 Section 420.67 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Separation distance requirements for handling incompatible energetic liquids that are co-located. 420.67 Section 420.67 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING...
The Development of the Zeppelin Dirigible for Long Distance Transportation
NASA Technical Reports Server (NTRS)
Ehrle, A.
1980-01-01
Changes in the design and construction of German airships for regular transoceanic passenger transportation during the 1916 to 1938 period are described. Technical problems related to structural weight, fuel reduction, and passenger comfort are considered.
NASA Technical Reports Server (NTRS)
Stickle, Joseph W.
1961-01-01
The National Aeronautics and Space Administration has recently completed a statistical investigation of landing-contact conditions for two large turbojet transports and a turboprop transport landing on a dry runway during routine daylight operations at the Los Angeles International Airport. Measurements were made to obtain vertical velocity, airspeed, rolling velocity, bank angle, and distance from the runway threshold, just prior to ground contact. The vertical velocities at touchdown for one of the turbojet airplanes measured in this investigation were essentially the same as those measured on the same type of airplane during a similar investigation (see NASA Technical Note D-527) conducted approximately 8 months earlier. Thus, it appeared that 8 months of additional pilot experience has had no noticeable tendency toward lowering the vertical velocities of this transport. Distributions of vertical velocities for the turbojet transports covered in this investigation were similar and considerably higher than'those for the turboprop transport. The data for the turboprop transport were in good agreement with the data for the piston-engine transports (see NACA Report 1214 and NASA Technical Note D-147) for all the measured parameters. For the turbojet transports, 1 landing in 100 would be expected to equal or exceed a vertical velocity of approximately 4.2 ft/sec; whereas, for the turboprop transport, 1 landing in 100 would be expected to equal or exceed 3.2 ft/sec. The mean airspeeds at touchdown for the three transports ranged from 22.5 percent to 26.6 percent above the stalling speed. Rolling velocities for the turbojet transports were considerably higher than those for the turboprop transport. Distributions of bank angles at contact for the three transports were similar. For each type of airplane, 1 landing in 100 would be expected to equal or exceed a bank angle at touchdown of approximately 3.0 deg. Distributions of touchdown distances for the three transports
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jelenska, Joanna; Davern, Sandra M.; Standaert, Robert F.
Diverse pathogen-derived molecules, such as bacterial flagellin and its conserved peptide flg22, are recognized in plants via plasma membrane receptors and induce both local and systemic immune responses. The fate of such ligands was unknown: whether and by what mechanism(s) they enter plant cells and whether they are transported to distal tissues. We used biologically active fluorophore and radiolabeled peptides to establish that flg22 moves to distal organs with the closest vascular connections. Remarkably, entry into the plant cell via endocytosis together with the FLS2 receptor is needed for delivery to vascular tissue and long-distance transport of flg22. This contrastsmore » with known routes of long distance transport of other non-cell-permeant molecules in plants, which require membrane-localized transporters for entry to vascular tissue. Thus, a plasma membrane receptor acts as a transporter to enable access of its ligand to distal trafficking routes.« less
Jelenska, Joanna; Davern, Sandra M.; Standaert, Robert F.; ...
2017-03-01
Diverse pathogen-derived molecules, such as bacterial flagellin and its conserved peptide flg22, are recognized in plants via plasma membrane receptors and induce both local and systemic immune responses. The fate of such ligands was unknown: whether and by what mechanism(s) they enter plant cells and whether they are transported to distal tissues. We used biologically active fluorophore and radiolabeled peptides to establish that flg22 moves to distal organs with the closest vascular connections. Remarkably, entry into the plant cell via endocytosis together with the FLS2 receptor is needed for delivery to vascular tissue and long-distance transport of flg22. This contrastsmore » with known routes of long distance transport of other non-cell-permeant molecules in plants, which require membrane-localized transporters for entry to vascular tissue. Thus, a plasma membrane receptor acts as a transporter to enable access of its ligand to distal trafficking routes.« less
NASA Astrophysics Data System (ADS)
Philip, Sajeev; Martin, Randall V.; Keller, Christoph A.
2016-05-01
Chemistry-transport models involve considerable computational expense. Fine temporal resolution offers accuracy at the expense of computation time. Assessment is needed of the sensitivity of simulation accuracy to the duration of chemical and transport operators. We conduct a series of simulations with the GEOS-Chem chemistry-transport model at different temporal and spatial resolutions to examine the sensitivity of simulated atmospheric composition to operator duration. Subsequently, we compare the species simulated with operator durations from 10 to 60 min as typically used by global chemistry-transport models, and identify the operator durations that optimize both computational expense and simulation accuracy. We find that longer continuous transport operator duration increases concentrations of emitted species such as nitrogen oxides and carbon monoxide since a more homogeneous distribution reduces loss through chemical reactions and dry deposition. The increased concentrations of ozone precursors increase ozone production with longer transport operator duration. Longer chemical operator duration decreases sulfate and ammonium but increases nitrate due to feedbacks with in-cloud sulfur dioxide oxidation and aerosol thermodynamics. The simulation duration decreases by up to a factor of 5 from fine (5 min) to coarse (60 min) operator duration. We assess the change in simulation accuracy with resolution by comparing the root mean square difference in ground-level concentrations of nitrogen oxides, secondary inorganic aerosols, ozone and carbon monoxide with a finer temporal or spatial resolution taken as "truth". Relative simulation error for these species increases by more than a factor of 5 from the shortest (5 min) to longest (60 min) operator duration. Chemical operator duration twice that of the transport operator duration offers more simulation accuracy per unit computation. However, the relative simulation error from coarser spatial resolution generally
Long-range energy transport in single supramolecular nanofibres at room temperature
NASA Astrophysics Data System (ADS)
Haedler, Andreas T.; Kreger, Klaus; Issac, Abey; Wittmann, Bernd; Kivala, Milan; Hammer, Natalie; Köhler, Jürgen; Schmidt, Hans-Werner; Hildner, Richard
2015-07-01
Efficient transport of excitation energy over long distances is a key process in light-harvesting systems, as well as in molecular electronics. However, in synthetic disordered organic materials, the exciton diffusion length is typically only around 10 nanometres (refs 4, 5), or about 50 nanometres in exceptional cases, a distance that is largely determined by the probability laws of incoherent exciton hopping. Only for highly ordered organic systems has the transport of excitation energy over macroscopic distances been reported--for example, for triplet excitons in anthracene single crystals at room temperature, as well as along single polydiacetylene chains embedded in their monomer crystalline matrix at cryogenic temperatures (at 10 kelvin, or -263 degrees Celsius). For supramolecular nanostructures, uniaxial long-range transport has not been demonstrated at room temperature. Here we show that individual self-assembled nanofibres with molecular-scale diameter efficiently transport singlet excitons at ambient conditions over more than four micrometres, a distance that is limited only by the fibre length. Our data suggest that this remarkable long-range transport is predominantly coherent. Such coherent long-range transport is achieved by one-dimensional self-assembly of supramolecular building blocks, based on carbonyl-bridged triarylamines, into well defined H-type aggregates (in which individual monomers are aligned cofacially) with substantial electronic interactions. These findings may facilitate the development of organic nanophotonic devices and quantum information technology.
Horses for courses: a DNA-based test for race distance aptitude in thoroughbred racehorses.
Hill, Emmeline W; Ryan, Donal P; MacHugh, David E
2012-12-01
Variation at the myostatin (MSTN) gene locus has been shown to influence racing phenotypes in Thoroughbred horses, and in particular, early skeletal muscle development and the aptitude for racing at short distances. Specifically, a single nucleotide polymorphism (SNP) in the first intron of MSTN (g.66493737C/T) is highly predictive of best race distance among Flat racing Thoroughbreds: homozygous C/C horses are best suited to short distance races, heterozygous C/T horses are best suited to middle distance races, and homozygous T/T horses are best suited to longer distance races. Patent applications for this gene marker association, and other linked markers, have been filed. The information contained within the patent applications is exclusively licensed to the commercial biotechnology company Equinome Ltd, which provides a DNA-based test to the international Thoroughbred horse racing and breeding industry. The application of this information in the industry enables informed decision making in breeding and racing and can be used to assist selection to accelerate the rate of change of genetic types among distinct populations (Case Study 1) and within individual breeding operations (Case Study 2).
Wood, Petra Bohall
2009-01-01
I used band recovery data to examine distances between banding and recovery locations for 154 nestling Florida Bald Eagles and discuss the implications for understanding natal dispersal and philopatry in this species. Band recoveries occurred in 23 U.S. states and five Canadian provinces between 1931–2005. Recovery distance from the natal nest averaged longer for the youngest age classes (ANOVA: F = 3.59; df = 5, 153; P = 0.005), for individuals banded in earlier decades (F = 1.94; df = 5, 153; P = 0.093), and for the months of May through October (F = 3.10; df = 12, 153;P < 0.001). Of 35 individuals classed as mature (≥3.9 yr old when recovered; range 3.9–36.5 yr), 31 were located within Florida, which suggested a strong degree of philopatry to the natal state. Among 21 mature eagles of known sex with known banding and recovery locations in Florida, females, particularly younger birds, had longer recovery distances (N = 9, mean = 93 km, SE = 22.4) than did males (N = 12, mean = 31 km, SE = 5.3; t = 2.67, df = 19, P = 0.026). The records examined here suggest a high degree of philopatry and relatively short natal dispersal distances, particularly in male Bald Eagles.
Evaluation of Contrail Reduction Strategies Based on Aircraft Flight Distances
NASA Technical Reports Server (NTRS)
Chen, Neil Y.; Sridhar, Banavar; Li, Jinhua; Ng, Hok Kwan
2012-01-01
This paper evaluates a set of contrail reduction strategies based on the flight range of aircraft as contrail reduction strategies have different impacts on aircraft depending on how they plan to fly. In general, aircraft with longer flight distances cruise at the altitudes where contrails are more likely to form. The concept of the contrail frequency index is used to quantify contrail impacts. The strategy for reducing the persistent contrail formation is to minimize the contrail frequency index by altering the aircraft's cruising altitude. A user-defined factor is used to trade off between contrail reduction and extra CO2 emissions. A higher value of tradeoff factor results in more contrail reduction and extra CO2 emissions. Results show that contrail reduction strategies using various tradeo factors behave differently from short-range flights to long-range ights. Analysis shows that short-distance flights (less than 500 miles) are the most frequent flights but contribute least to contrail reduction. Therefore these aircraft have the lowest priority when applying contrail reduction strategies. Medium-distance flights (500 to 1000 miles) have a higher priority if the goal is to achieve maximum contrail reduction in total; long-distance flights (1000 to 1500 miles) have a higher priority if the goal is to achieve maximum contrail reduction per flight. The characteristics of transcontinental flights (greater than 1500 miles) vary with different weather days so the priority of applying contrail reduction strategies to the group needs to be evaluated based on the locations of the contrail areas during any given day. For the days tested, medium-distance ights contribute up to 42.6% of the reduction among the groups during a day. The contrail frequency index per 1,000 miles for medium-distance, long-distance, and transcontinental flights can be reduced by an average of 75%. The results provide a starting point for developing operational policies to reduce the impact of
Clast comminution during pyroclastic density current transport: Mt St Helens
NASA Astrophysics Data System (ADS)
Dawson, B.; Brand, B. D.; Dufek, J.
2011-12-01
Volcanic clasts within pyroclastic density currents (PDCs) tend to be more rounded than those in fall deposits. This rounding reflects degrees of comminution during transport, which produces an increase in fine-grained ash with distance from source (Manga, M., Patel, A., Dufek., J. 2011. Bull Volcanol 73: 321-333). The amount of ash produced due to comminution can potentially affect runout distance, deposit sorting, the volume of ash lofted into the upper atmosphere, and increase internal pore pressure (e.g., Wohletz, K., Sheridan, M. F., Brown, W.K. 1989. J Geophy Res, 94, 15703-15721). For example, increased pore pressure has been shown to produce longer runout distances than non-comminuted PDC flows (e.g., Dufek, J., and M. Manga, 2008. J. Geophy Res, 113). We build on the work of Manga et al., (2011) by completing a pumice abrasion study for two well-exposed flow units from the May 18th, 1980 eruption of Mt St Helens (MSH). To quantify differences in comminution from source, sampling and the image analysis technique developed in Manga et al., 2010 was completed at distances proximal, medial, and distal from source. Within the units observed, data was taken from the base, middle, and pumice lobes within the outcrops. Our study is unique in that in addition to quantifying the degree of pumice rounding with distance from source, we also determine the possible range of ash sizes produced during comminution by analyzing bubble wall thickness of the pumice through petrographic and SEM analysis. The proportion of this ash size is then measured relative to the grain size of larger ash with distance from source. This allows us to correlate ash production with degree of rounding with distance from source, and determine the fraction of the fine ash produced due to comminution versus vent-fragmentation mechanisms. In addition we test the error in 2D analysis by completing a 3D image analysis of selected pumice samples using a Camsizer. We find that the roundness of PDC
The Influence of Turbulent Coherent Structure on Suspended Sediment Transport
NASA Astrophysics Data System (ADS)
Huang, S. H.; Tsai, C.
2017-12-01
The anomalous diffusion of turbulent sedimentation has received more and more attention in recent years. With the advent of new instruments and technologies, researchers have found that sediment behavior may deviate from Fickian assumptions when particles are heavier. In particle-laden flow, bursting phenomena affects instantaneous local concentrations, and seems to carry suspended particles for a longer distance. Instead of the pure diffusion process in an analogy to Brownian motion, Levy flight which allows particles to move in response to bursting phenomena is suspected to be more suitable for describing particle movement in turbulence. And the fractional differential equation is a potential candidate to improve the concentration profile. However, stochastic modeling (the Differential Chapmen-Kolmogorov Equation) also provides an alternative mathematical framework to describe system transits between different states through diffusion/the jump processes. Within this framework, the stochastic particle tracking model linked with advection diffusion equation is a powerful tool to simulate particle locations in the flow field. By including the jump process to this model, a more comprehensive description for suspended sediment transport can be provided with a better physical insight. This study also shows the adaptability and expandability of the stochastic particle tracking model for suspended sediment transport modeling.
Djurhuus, Sune; Hansen, Henning Sten; Aadahl, Mette; Glümer, Charlotte
2014-01-01
Active commuters have lower risk of chronic disease. Understanding which of the, to some extent, modifiable characteristics of public transportation that facilitate its use is thus important in a public health perspective. The aim of the study was to examine the association between individual public transportation accessibility and self-reported active commuting, and whether the associations varied with commute distance, age, and gender. Twenty-eight thousand nine hundred twenty-eight commuters in The Capital Region of Denmark reported self-reported time spent either walking or cycling to work or study each day and the distance to work or study. Data were obtained from the Danish National Health Survey collected in February to April 2010. Individual accessibility by public transportation was calculated using a multi-modal network in a GIS. Multilevel logistic regression was used to analyze the association between accessibility, expressed as access area, and being an active commuter. Public transport accessibility area based on all stops within walking and cycling distance was positively associated with being an active commuter. Distance to work, age, and gender modified the associations. Residing within 10 km commute distance and in areas of high accessibility was associated with being an active commuter and meeting the recommendations of physical activity. For the respondents above 29 years, individual public transportation accessibility was positively associated with being an active commuter. Women having high accessibility had significantly higher odds of being an active commuter compared to having a low accessibility. For men, the associations were insignificant. This study extends the knowledge about the driving forces of using public transportation for commuting by examining the individual public transportation accessibility. Findings suggest that transportation accessibility supports active commuting and planning of improved public transit accessibility
Djurhuus, Sune; Hansen, Henning Sten; Aadahl, Mette; Glümer, Charlotte
2014-01-01
Background: Active commuters have lower risk of chronic disease. Understanding which of the, to some extent, modifiable characteristics of public transportation that facilitate its use is thus important in a public health perspective. The aim of the study was to examine the association between individual public transportation accessibility and self-reported active commuting, and whether the associations varied with commute distance, age, and gender. Methods: Twenty-eight thousand nine hundred twenty-eight commuters in The Capital Region of Denmark reported self-reported time spent either walking or cycling to work or study each day and the distance to work or study. Data were obtained from the Danish National Health Survey collected in February to April 2010. Individual accessibility by public transportation was calculated using a multi-modal network in a GIS. Multilevel logistic regression was used to analyze the association between accessibility, expressed as access area, and being an active commuter. Results: Public transport accessibility area based on all stops within walking and cycling distance was positively associated with being an active commuter. Distance to work, age, and gender modified the associations. Residing within 10 km commute distance and in areas of high accessibility was associated with being an active commuter and meeting the recommendations of physical activity. For the respondents above 29 years, individual public transportation accessibility was positively associated with being an active commuter. Women having high accessibility had significantly higher odds of being an active commuter compared to having a low accessibility. For men, the associations were insignificant. Conclusion: This study extends the knowledge about the driving forces of using public transportation for commuting by examining the individual public transportation accessibility. Findings suggest that transportation accessibility supports active commuting and planning
Celebrating Distance Teaching Innovations: The Certificate in Distance Teaching.
ERIC Educational Resources Information Center
Boylan, Colin; Tuovinen, Juhani
Charles Sturt University (Riverina, Australia) has initiated the Certificate in Distance Teaching course for rural teachers working in a distance education setting to extend their understandings about rural and distance education topics. Two semester-long subjects constitute the course: pedagogy of distance teaching and organization of distance…
Spatial interpolation of river channel topography using the shortest temporal distance
NASA Astrophysics Data System (ADS)
Zhang, Yanjun; Xian, Cuiling; Chen, Huajin; Grieneisen, Michael L.; Liu, Jiaming; Zhang, Minghua
2016-11-01
It is difficult to interpolate river channel topography due to complex anisotropy. As the anisotropy is often caused by river flow, especially the hydrodynamic and transport mechanisms, it is reasonable to incorporate flow velocity into topography interpolator for decreasing the effect of anisotropy. In this study, two new distance metrics defined as the time taken by water flow to travel between two locations are developed, and replace the spatial distance metric or Euclidean distance that is currently used to interpolate topography. One is a shortest temporal distance (STD) metric. The temporal distance (TD) of a path between two nodes is calculated by spatial distance divided by the tangent component of flow velocity along the path, and the STD is searched using the Dijkstra algorithm in all possible paths between two nodes. The other is a modified shortest temporal distance (MSTD) metric in which both the tangent and normal components of flow velocity were combined. They are used to construct the methods for the interpolation of river channel topography. The proposed methods are used to generate the topography of Wuhan Section of Changjiang River and compared with Universal Kriging (UK) and Inverse Distance Weighting (IDW). The results clearly showed that the STD and MSTD based on flow velocity were reliable spatial interpolators. The MSTD, followed by the STD, presents improvement in prediction accuracy relative to both UK and IDW.
Distance Training as Part of a Distance Consulting Solution.
ERIC Educational Resources Information Center
Fulantelli, Giovanni; Chiazzese, Giuseppe; Allegra, Mario
"Distance Training" models, when integrated in a more complex framework, such as a "Distance Consulting" model, present specific features and impose a revision of the strategies commonly adopted in distance training experiences. This paper reports on the distance training strategies adopted in a European funded project aimed at…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilmot, E.L.; Shirley, C.G.
1982-01-01
Results presented in this paper show that almost any compact binding states into cooperating regions for disposal of LLW will reduce nationwide transportation costs markedly. As a corollary, the reduction of costs may reflect a two- to four-fold reduction of transportation distances with consequent reduction of risk to the public since risk generally decreases directly as transport distances decrease.
ERIC Educational Resources Information Center
Ramaswami, Rama
2009-01-01
With hundreds of K-12 schools routinely offering online courses, the idea of a full-time virtual school is no longer as outlandish as it once may have seemed. Thanks to giant improvements in technology and the quality of their academic instruction, most virtual schools now hold a trump card they had not possessed: credibility. "There were…
NASA Astrophysics Data System (ADS)
Tucker, G. E.; Bradley, D. N.
2008-12-01
Many geomorphic transport laws assume that the transport process is local, meaning that the space and time scales of particle displacement are short relative to those of the system as a whole. This assumption allows one to express sediment flux in terms of at-a-point properties such as the local surface gradient. However, while this assumption is quite reasonable for some processes (for example, grain displacement by raindrop impact), it is questionable for others (such as landsliding). Moreover, particle displacement distance may also depend on slope angle, becoming longer as gradient increases. For example, the average motion distance during sediment ravel events on very steep slopes may approach the length of the entire hillslope. In such cases, the mass flux through a given point may depend not only on the local topography but also on topography some distance upslope, thus violating the locality assumption. Here we use a stochastic, particle- based model of hillslope evolution to gain insight into the potential for, and consequences of, nonlocality in sediment transport. The model is designed as a simple analogy for a host of different processes that displace sediment grains on hillslopes. The hillslope is represented as a two-dimensional pile of particles. These particles undergo quasi-random motion according to the following rules: (1) during each iteration, a particle and a direction are selected at random; (2) the particle hops in the direction of motion with a probability that depends on the its height relative to that of its immediate neighbor; (3) the particle continues making hops in the same direction and with the same probability dependence, until coming to rest or exiting the base of the slope. The topography and motion statistics that emerge from these rules show a range of behavior that depends on a dimensionless relief parameter. At low relief, hillslope shape is parabolic, mean displacement length is on the order of two particle widths, and the
Polarization vision seldom increases the sighting distance of silvery fish.
Johnsen, Sönke; Gagnon, Yakir L; Marshall, N Justin; Cronin, Thomas W; Gruev, Viktor; Powell, Samuel
2016-08-22
Although the function of polarization vision, the ability to discern the polarization characteristics of light, is well established in many terrestrial and benthic species, its purpose in pelagic species (squid and certain fish and crustaceans) is poorly understood [1]. A long-held hypothesis is that polarization vision in open water is used to break the mirror camouflage of silvery fish, as biological mirrors can change the polarization of reflected light [2,3]. Although, the addition of polarization information may increase the conspicuousness of silvery fish at close range, direct evidence that silvery fish - or indeed any pelagic animal - are visible at longer distances using polarization vision rather than using radiance (i.e. brightness) vision is lacking. Here we show, using in situ polarization imagery and a new visual detection model, that polarization vision does not in fact appear to allow viewers to see silvery fish at greater distances. Copyright © 2016 Elsevier Ltd. All rights reserved.
Distance learning through synchronous interactive television.
Hall, Janis L
2007-01-01
The advent and popularity of asynchronous online learning has somewhat obscured a standby technology developed over the last two decades. Interactive videoconferencing, sometimes called "interactive television," though not as glamorous and popular a topic at distance-learning conferences, is still alive and well at many institutions. Three or four years ago, many of us were led to believe that interactive television would go the way of the dinosaurs-everything would soon be in an asynchronous format or on individual desktops. There would no longer be any need for elaborately designed classrooms, networks, and operations staff. To date, this prediction has not come true. In fact, synchronous interactive television has experienced significant growth as newer, easier, and cheaper technologies allow institutions to reach more students with less resource investment. Faculty and students, while appreciating the convenience of asynchronous delivery, still express a need for synchronous communication. This article explores the issues involved in synchronous distance education, the current technologies and proposed future developments, and best practices in terms of classroom design, faculty use, and operational issues. It is not a research article but an anecdotal case study based on Washington State University's experiences over the last 20 years in developing and adapting to new synchronous technologies and creating the support and technical infrastructure to best deliver academic courses through this medium.
49 CFR 325.73 - Microphone distance correction factors. 1
Code of Federal Regulations, 2013 CFR
2013-10-01
... the observed sound level reading is— 31 feet (9.5 m) or more but less than 35 feet (10.7 m) −4 35 feet... more but less than 83 feet (25.3 m) +2 [40 FR 42437, Sept. 12, 1975, as amended at 54 FR 50385, Dec. 6... 49 Transportation 5 2013-10-01 2013-10-01 false Microphone distance correction factors. 1 325.73...
49 CFR 325.73 - Microphone distance correction factors. 1
Code of Federal Regulations, 2012 CFR
2012-10-01
... the observed sound level reading is— 31 feet (9.5 m) or more but less than 35 feet (10.7 m) −4 35 feet... more but less than 83 feet (25.3 m) +2 [40 FR 42437, Sept. 12, 1975, as amended at 54 FR 50385, Dec. 6... 49 Transportation 5 2012-10-01 2012-10-01 false Microphone distance correction factors. 1 325.73...
49 CFR 325.73 - Microphone distance correction factors. 1
Code of Federal Regulations, 2014 CFR
2014-10-01
... the observed sound level reading is— 31 feet (9.5 m) or more but less than 35 feet (10.7 m) −4 35 feet... more but less than 83 feet (25.3 m) +2 [40 FR 42437, Sept. 12, 1975, as amended at 54 FR 50385, Dec. 6... 49 Transportation 5 2014-10-01 2014-10-01 false Microphone distance correction factors. 1 325.73...
Logistics in the cell: cargoes and transportation.
Nadezhdina, E S
2014-09-01
Eukaryotic cells are large and thus require a vesicular transport system. The system involves the formation of membrane transport containers, their short- and long-distance movements, recognition of destination points, and fusion with other membranes. Understanding the molecular mechanisms of these processes is of theoretical and practical significance. This special issue of Biochemistry (Moscow) collects surveys and experimental articles describing various aspects of vesicular transport.
Longer aftershocks duration in extensional tectonic settings.
Valerio, E; Tizzani, P; Carminati, E; Doglioni, C
2017-11-27
Aftershocks number decay through time, depending on several parameters peculiar to each seismogenic regions, including mainshock magnitude, crustal rheology, and stress changes along the fault. However, the exact role of these parameters in controlling the duration of the aftershock sequence is still unknown. Here, using two methodologies, we show that the tectonic setting primarily controls the duration of aftershocks. On average and for a given mainshock magnitude (1) aftershock sequences are longer and (2) the number of earthquakes is greater in extensional tectonic settings than in contractional ones. We interpret this difference as related to the different type of energy dissipated during earthquakes. In detail, (1) a joint effect of gravitational forces and pure elastic stress release governs extensional earthquakes, whereas (2) pure elastic stress release controls contractional earthquakes. Accordingly, normal faults operate in favour of gravity, preserving inertia for a longer period and seismicity lasts until gravitational equilibrium is reached. Vice versa, thrusts act against gravity, exhaust their inertia faster and the elastic energy dissipation is buffered by the gravitational force. Hence, for seismic sequences of comparable magnitude and rheological parameters, aftershocks last longer in extensional settings because gravity favours the collapse of the hangingwall volumes.
Construction of Multimodal Transport Information Platform
NASA Astrophysics Data System (ADS)
Wang, Ya; Cheng, Yu; Zhao, Zhi
2018-06-01
With the rapid development of economy, the volume of transportation in China is increasing, the opening process of the market is accelerating, the scale of enterprises is expanding, the service quality is being improved, and the container multimodal transport is developing continuously.The hardware infrastructure of container multimodal transport is improved obviously, but the network platform construction of multimodal transport is still insufficient.Taking Shandong region of China as an example, the present situation of container multimodal transport in Shandong area can no longer meet the requirement of rapid development of container, and the construction of network platform needs to be solved urgently. Therefore, this paper will briefly describe the conception of construction of multimodal transport network platform in Shandong area.In order to achieve the rapid development of multimodal transport.
Dissemination of evidence-based practice: can we train therapists from a distance?
Vismara, Laurie A; Young, Gregory S; Stahmer, Aubyn C; Griffith, Elizabeth McMahon; Rogers, Sally J
2009-12-01
Although knowledge about the efficacy of behavioral interventions for children with ASD is increasing, studies of effectiveness and transportability to community settings are needed. The current study conducted an effectiveness trial to compare distance learning vs. live instruction for training community-based therapists to implement the Early Start Denver Model. Findings revealed: (a) distance learning and live instruction were equally effective for teaching therapists to both implement the model and to train parents; (b) didactic workshops and team supervision were required to improve therapists' skill use; (c) significant child gains occurred over time and across teaching modalities; and (d) parents implemented the model more skillfully after coaching. Implications are discussed in relation to the economic and clinical utility of distance learning.
Effect of Geographic Distance on Distance Education: An Empirical Study
ERIC Educational Resources Information Center
Luo, Heng; Robinson, Anthony C.; Detwiler, Jim
2014-01-01
This study investigates the effect of geographic distance on students' distance learning experience with the aim to provide tentative answers to a fundamental question--does geographic distance matter in distance education? Using educational outcome data collected from an online master's program in Geographic Information Systems, this study…
NASA Astrophysics Data System (ADS)
Tyurina, E. A.; Mednikov, A. S.
2017-11-01
The paper presents the results of studies on the perspective technologies of natural gas conversion to synthetic liquid fuel (SLF) at energy-technology installations for combined production of SLF and electricity based on their detailed mathematical models. The technologies of the long-distance transport of energy of natural gas from large fields to final consumers are compared in terms of their efficiency. This work was carried out at Melentiev Energy Systems Institute of Siberian Branch of the Russian Academy of Sciences and supported by Russian Science Foundation via grant No 16-19-10174
ERIC Educational Resources Information Center
Orey, Michael; Koenecke, Lynne; Snider, Richard C.; Perkins, Ross A.; Holmes, Glen A.; Lockee, Barbara B.; Moller, Leslie A.; Harvey, Douglas; Downs, Margaret; Godshalk, Veronica M.
2003-01-01
Contains four articles covering trends and issues on distance learning including: the experience of two learners learning via the Internet; a systematic approach to determining the scalability of a distance education program; identifying factors that affect learning community development and performance in asynchronous distance education; and…
ERIC Educational Resources Information Center
ASPBAE Courier, 1984
1984-01-01
This publication is devoted to distance education. "The Future of Distance Teaching Universities in a Worldwide Perspectives" (John S. Daniel) examines challenges likely to face the various countries and regions of the world in the next decade. "An Australian University's Approach to Distance Education--Formal and Non-Formal"…
Particle tracking acceleration via signed distance fields in direct-accelerated geometry Monte Carlo
Shriwise, Patrick C.; Davis, Andrew; Jacobson, Lucas J.; ...
2017-08-26
Computer-aided design (CAD)-based Monte Carlo radiation transport is of value to the nuclear engineering community for its ability to conduct transport on high-fidelity models of nuclear systems, but it is more computationally expensive than native geometry representations. This work describes the adaptation of a rendering data structure, the signed distance field, as a geometric query tool for accelerating CAD-based transport in the direct-accelerated geometry Monte Carlo toolkit. Demonstrations of its effectiveness are shown for several problems. The beginnings of a predictive model for the data structure's utilization based on various problem parameters is also introduced.
Dissemination of Evidence-Based Practice: Can We Train Therapists from a Distance?
ERIC Educational Resources Information Center
Vismara, Laurie A.; Young, Gregory S.; Stahmer, Aubyn C.; Griffith, Elizabeth McMahon; Rogers, Sally J.
2009-01-01
Although knowledge about the efficacy of behavioral interventions for children with ASD is increasing, studies of effectiveness and transportability to community settings are needed. The current study conducted an effectiveness trial to compare distance learning vs. live instruction for training community-based therapists to implement the Early…
Intercontinental Transport of Air Pollution
NASA Technical Reports Server (NTRS)
Rogers, David; Whung, Pai-Yei; Einaudi, Franco (Technical Monitor)
2001-01-01
The development of the global economy goes beyond raising our standards of living. We are in an ear of increasing environmental as well as economic interdependence. Long-range transport of anthropogenic atmospheric pollutants such as ozone, ozone precursors, airborne particles, heavy metals (such as mercury) and persistent organic pollutants are the four major types of pollution that are transported over intercontinental distances and have global environmental effects. The talk includes: 1) an overview of the international agreements related to intercontinental transport of air pollutants, 2) information needed for decision making, 3) overview of the past research on intercontinental transport of air pollutants - a North American's perspective, and 4) future research needs.
Optimal partial mass transportation and obstacle Monge-Kantorovich equation
NASA Astrophysics Data System (ADS)
Igbida, Noureddine; Nguyen, Van Thanh
2018-05-01
Optimal partial mass transport, which is a variant of the optimal transport problem, consists in transporting effectively a prescribed amount of mass from a source to a target. The problem was first studied by Caffarelli and McCann (2010) [6] and Figalli (2010) [12] with a particular attention to the quadratic cost. Our aim here is to study the optimal partial mass transport problem with Finsler distance costs including the Monge cost given by the Euclidian distance. Our approach is different and our results do not follow from previous works. Among our results, we introduce a PDE of Monge-Kantorovich type with a double obstacle to characterize active submeasures, Kantorovich potential and optimal flow for the optimal partial transport problem. This new PDE enables us to study the uniqueness and monotonicity results for the active submeasures. Another interesting issue of our approach is its convenience for numerical analysis and computations that we develop in a separate paper [14] (Igbida and Nguyen, 2018).
Recycling of Kinesin-1 Motors by Diffusion after Transport
Blasius, T. Lynne; Reed, Nathan; Slepchenko, Boris M.; Verhey, Kristen J.
2013-01-01
Kinesin motors drive the long-distance anterograde transport of cellular components along microtubule tracks. Kinesin-dependent transport plays a critical role in neurogenesis and neuronal function due to the large distance separating the soma and nerve terminal. The fate of kinesin motors after delivery of their cargoes is unknown but has been postulated to involve degradation at the nerve terminal, recycling via retrograde motors, and/or recycling via diffusion. We set out to test these models concerning the fate of kinesin-1 motors after completion of transport in neuronal cells. We find that kinesin-1 motors are neither degraded nor returned by retrograde motors. By combining mathematical modeling and experimental analysis, we propose a model in which the distribution and recycling of kinesin-1 motors fits a “loose bucket brigade” where individual motors alter between periods of active transport and free diffusion within neuronal processes. These results suggest that individual kinesin-1 motors are utilized for multiple rounds of transport. PMID:24098765
Stewart, Camille L; Metzger, Ryan R; Pyle, Laura; Darmofal, Joe; Scaife, Eric; Moulton, Steven L
2015-02-01
Helicopter emergency medical services (HEMS) are a common mode of transportation for pediatric trauma patients. We hypothesized that HEMS improve outcomes for traumatically injured children compared to ground emergency medical services (GEMS). We queried trauma registries of two level 1 pediatric trauma centers for children 0-17 years, treated from 2003 to 2013, transported by HEMS or GEMS, with known transport starting location and outcome. A geocoding service estimated travel distance and time. Multivariate regression analyses were performed to adjust for injury severity variables and travel distance/time. We identified 14,405 traumatically injured children; 3870 (26.9%) transported by HEMS and 10,535 (73.1%) transported by GEMS. Transport type was not significantly associated with survival, ICU length of stay, or discharge disposition. Transport by GEMS was associated with a 68.6%-53.1% decrease in hospital length of stay, depending on adjustment for distance/time. Results were similar for children with severe injuries, and with propensity score matched cohorts. Of note, 862/3850 (22.3%) of HEMS transports had an ISS<10 and hospitalization<1 day. HEMS do not independently improve outcomes for traumatically injured children, and 22.3% of children transported by HEMS are not significantly injured. These factors should be considered when requesting HEMS for transport of traumatically injured children. Copyright © 2015 Elsevier Inc. All rights reserved.
Atik, Fernando Antibas; Couto, Carolina Fatima; Tirado, Freddy Ponce; Moraes, Camila Scatolin; Chaves, Renato Bueno; Vieira, Nubia W; Reis, João Gabbardo
2014-01-01
Evaluate the addition of long-distance heart procurement on a heart transplant program and the status of heart transplant recipients waiting list. Between September 2006 and October 2012, 72 patients were listed as heart transplant recipients. Heart transplant was performed in 41 (57%), death on the waiting list occurred in 26 (36%) and heart recovery occurred in 5 (7%). Initially, all transplants were performed with local donors. Long-distance, interstate heart procurement initiated in February 2011. Thirty (73%) transplants were performed with local donors and 11 (27%) with long-distance donors (mean distance=792 km±397). Patients submitted to interstate heart procurement had greater ischemic times (212 min ± 32 versus 90 min±18; P<0.0001). Primary graft dysfunction (distance 9.1% versus local 26.7%; P=0.23) and 1 month and 12 months actuarial survival (distance 90.1% and 90.1% versus local 90% and 86.2%; P=0.65 log rank) were similar among groups. There were marked incremental transplant center volume (64.4% versus 40.7%, P=0.05) with a tendency on less waiting list times (median 1.5 month versus 2.4 months, P=0.18). There was a tendency on reduced waiting list mortality (28.9% versus 48.2%, P=0.09). Incorporation of long-distance heart procurement, despite being associated with longer ischemic times, does not increase morbidity and mortality rates after heart transplant. It enhances viable donor pool, and it may reduce waiting list recipient mortality as well as waiting time.
Distance Courses in Mechanics and in Distance Instructor Training
ERIC Educational Resources Information Center
Karlsson, Goran
2004-01-01
This paper describes two related distance courses for instructor and leadership training and a distance undergraduate course in mechanics. Flexible and distance learning are becoming more and more important, so it is important to train instructors for such changes. KTH (Royal Institute of Technology, Stockholm) has the course "5C4502 Distance…
Schmidt, A; Biau, S; Möstl, E; Becker-Birck, M; Morillon, B; Aurich, J; Faure, J-M; Aurich, C
2010-04-01
It is widely accepted that transport is stressful for horses, but only a few studies are available involving horses that are transported regularly and are accustomed to transport. We determined salivary cortisol immunoreactivity (IR), fecal cortisol metabolites, beat-to-beat (RR) interval, and heart rate variability (HRV) in transport-experienced horses (N=7) in response to a 2-d outbound road transport over 1370 km and 2-d return transport 8 d later. Salivary cortisol IR was low until 60 min before transport but had increased (P<0.05) 30 min before loading. Transport caused a further marked increase (P<0.001), but the response tended to decrease with each day of transport. Concentrations of fecal cortisol metabolites increased on the second day of both outbound and return transports and reached a maximum the following day (P<0.001). During the first 90 min on Day 1 of outbound transport, mean RR interval decreased (P<0.001). Standard deviations of RR interval (SDRR) decreased transiently (P<0.01). The root mean square of successive RR differences (RMSSD) decreased at the beginning of the outbound and return transports (P<0.01), reflecting reduced parasympathetic tone. On the first day of both outbound and return transports, a transient rise in geometric HRV variable standard deviation 2 (SD2) occurred (P<0.01), indicating increased sympathetic activity. In conclusion, transport of experienced horses leads to increased cortisol release and changes in heart rate and HRV, which is indicative of stress. The degree of these changes tended to be most pronounced on the first day of both outbound and return transport. Copyright 2009 Elsevier Inc. All rights reserved.
Anderson, Roger C.
2018-01-01
Introduction Alliaria petiolata, an herbaceous plant, has invaded woodlands in North America. Its ecology has been thoroughly studied, but an overlooked aspect of its biology is seed dispersal distances and mechanisms. We measured seed dispersal distances in the field and tested if epizoochory is a potential mechanism for long-distance seed dispersal. Methods Dispersal distances were measured by placing seed traps in a sector design around three seed point sources, which consisted of 15 second-year plants transplanted within a 0.25 m radius circle. Traps were placed at intervals ranging from 0.25–3.25 m from the point source. Traps remained in the field until a majority of seeds were dispersed. Eight probability density functions were fitted to seed trap counts via maximum likelihood. Epizoochory was tested as a potential seed dispersal mechanism for A. petiolata through a combination of field and laboratory experiments. To test if small mammals transport A. petiolata seeds in their fur, experimental blocks were placed around dense A. petiolata patches. Each block contained a mammal inclusion treatment (MIT) and control. The MIT consisted of a wood-frame (31 × 61× 31 cm) covered in wire mesh, except for the two 31 × 31 cm ends, placed over a germination tray filled with potting soil. A pan filled with bait was placed in the center of the tray. The control frame (11 × 31 × 61 cm) was placed over a germination tray and completely covered in wire mesh to exclude animal activity. Treatments were in the field for peak seed dispersal. In March, trays were moved to a greenhouse and A. petiolata seedlings were counted and then compared between treatments. To determine if A. petiolata seeds attach to raccoon (Procyon lotor) and white-tailed deer (Odocoileus virginianus) fur, wet and dry seeds were dropped onto wet and dry fur. Furs were rotated 180 degrees and the seeds that remained attached were counted. To measure seed retention, seeds were dropped on
A National MagLev Transportation System
NASA Technical Reports Server (NTRS)
Wright, Michael R.
2003-01-01
The case for a national high-speed magnetic-levitation (MagLev) transportation system is presented. Focus is on current issues facing the country, such as national security, the economy, transportation, technology, and the environment. NASA s research into MagLev technology for launch assist is also highlighted. Further, current socio-cultural norms regarding motor-vehicle-based transportation systems are questioned in light of the problems currently facing the U.S. The multidisciplinary benefits of a long-distance MagLev system support the idea that such a system would be an important element of a truly multimodal U.S. transportation infrastructure.
Transportation of Critically Ill Patients on Extracorporeal Membrane Oxygenation
Broman, L. Mikael; Frenckner, Björn
2016-01-01
Extracorporeal membrane oxygenation (ECMO) may be a life-saving procedure for patients with severe reversible pulmonary or cardiac failure or for patients in need for a bridge to transplantation. ECMO is provided by specialized centers, but patients in need of ECMO are frequently taken care of at other centers. Conventional transports to an ECMO center can be hazardous and deaths have been described. For this reason, many ECMO centers have developed transport programs with mobile ECMO. After request, the mobile team including all necessary equipment to initiate ECMO is sent to the referring hospital, where the patient is cannulated and ECMO commenced. The patient is then transported on ECMO to the ECMO facility by road, helicopter, or fixed-wing aircraft depending on distance, weather conditions, etc. Eight publications have reported series of more than 50 transports on ECMO of which the largest included over 700. Together, these papers report on more than 1400 patient transports on ECMO. Two deaths during transport have occurred. A number of other adverse events are described, but without effect on patient outcome. Survival of patients transported on ECMO is equivalent to that of non-transported ECMO patients. It is concluded that long-, short-distance interhospital transports on ECMO can be performed safely. The staff should be experienced and highly competent in intensive care, ECMO cannulation, ECMO treatment, intensive care transport, and air transport medicine. PMID:27379221
The Effects of Distance to Dentists and Dentist Supply on Children's Use of Dental Care.
Wehby, George L; Shane, Dan M; Joshi, Adweta; Momany, Elizabeth; Chi, Donald L; Kuthy, Raymond A; Damiano, Peter C
2017-10-01
To examine the effects of distance to dentists and dentist supply on dental services use among children with Medicaid coverage in Iowa. Iowa Medicaid claims for enrolled children between 2000 and 2009. The study sample included 41,554 children (providing 158,942 child-year observations) who were born in Iowa between 2000 and 2006 and enrolled from birth in the Iowa Medicaid program. Children were followed through 2009. We used logistic regression to simultaneously examine the effects of distance (miles to nearest dentist) and county-level dentist supply on a broad range of dental services controlling for key confounders. Additional models only used within-child variation over time to remove unobservable time-invariant confounders. Distance was related to lower utilization of comprehensive dental exams (2 percent lower odds per 1 mile increase in distance), an effect that also held in models using within-child variation only. Dentist supply was positively related to comprehensive exams and other preventive services and negatively related to major dental treatments; however, these associations became smaller and insignificant when examining within-child changes except for other preventive services. Longer distance to dentists is a barrier for use of comprehensive dental exams, conditional on dentist supply. © Health Research and Educational Trust.
2H{ 19F} REDOR for distance measurements in biological solids using a double resonance spectrometer
NASA Astrophysics Data System (ADS)
Grage, Stephan L.; Watts, Jude A.; Watts, Anthony
2004-01-01
A new approach for distance measurements in biological solids employing 2H{ 19F} rotational echo double resonance was developed and validated on 2H, 19F- D-alanine and an imidazopyridine based inhibitor of the gastric H +/K +-ATPase. The 2H- 19F double resonance experiments presented here were performed without 1H decoupling using a double resonance NMR spectrometer. In this way, it was possible to benefit from the relatively longer distance range of fluorine without the need of specialized fluorine equipment. A distance of 2.5 ± 0.3 Å was measured in the alanine derivative, indicating a gauche conformation of the two labels. In the case of the imidazopyridine compound a lower distance limit of 5.2 Å was determined and is in agreement with an extended conformation of the inhibitor. Several REDOR variants were compared, and their advantages and limitations discussed. Composite fluorine dephasing pulses were found to enhance the frequency bandwidth significantly, and to reduce the dependence of the performance of the experiment on the exact choice of the transmitter frequency.
Van Cauwenberg, Jelle; Clarys, Peter; De Bourdeaudhuij, Ilse; Van Holle, Veerle; Verté, Dominique; De Witte, Nico; De Donder, Liesbeth; Buffel, Tine; Dury, Sarah; Deforche, Benedicte
2013-08-14
The physical environment may play a crucial role in promoting older adults' walking for transportation. However, previous studies on relationships between the physical environment and older adults' physical activity behaviors have reported inconsistent findings. A possible explanation for these inconsistencies is the focus upon studying environmental factors separately rather than simultaneously. The current study aimed to investigate the cumulative influence of perceived favorable environmental factors on older adults' walking for transportation. Additionally, the moderating effect of perceived distance to destinations on this relationship was studied. The sample was comprised of 50,685 non-institutionalized older adults residing in Flanders (Belgium). Cross-sectional data on demographics, environmental perceptions and frequency of walking for transportation were collected by self-administered questionnaires in the period 2004-2010. Perceived distance to destinations was categorized into short, medium, and large distance to destinations. An environmental index (=a sum of favorable environmental factors, ranging from 0 to 7) was constructed to investigate the cumulative influence of favorable environmental factors. Multilevel logistic regression analyses were applied to predict probabilities of daily walking for transportation. For short distance to destinations, probability of daily walking for transportation was significantly higher when seven compared to three, four or five favorable environmental factors were present. For medium distance to destinations, probabilities significantly increased for an increase from zero to four favorable environmental factors. For large distance to destinations, no relationship between the environmental index and walking for transportation was observed. Our findings suggest that the presence of multiple favorable environmental factors can motivate older adults to walk medium distances to facilities. Future research should focus
2013-01-01
Background The physical environment may play a crucial role in promoting older adults’ walking for transportation. However, previous studies on relationships between the physical environment and older adults’ physical activity behaviors have reported inconsistent findings. A possible explanation for these inconsistencies is the focus upon studying environmental factors separately rather than simultaneously. The current study aimed to investigate the cumulative influence of perceived favorable environmental factors on older adults’ walking for transportation. Additionally, the moderating effect of perceived distance to destinations on this relationship was studied. Methods The sample was comprised of 50,685 non-institutionalized older adults residing in Flanders (Belgium). Cross-sectional data on demographics, environmental perceptions and frequency of walking for transportation were collected by self-administered questionnaires in the period 2004-2010. Perceived distance to destinations was categorized into short, medium, and large distance to destinations. An environmental index (=a sum of favorable environmental factors, ranging from 0 to 7) was constructed to investigate the cumulative influence of favorable environmental factors. Multilevel logistic regression analyses were applied to predict probabilities of daily walking for transportation. Results For short distance to destinations, probability of daily walking for transportation was significantly higher when seven compared to three, four or five favorable environmental factors were present. For medium distance to destinations, probabilities significantly increased for an increase from zero to four favorable environmental factors. For large distance to destinations, no relationship between the environmental index and walking for transportation was observed. Conclusions Our findings suggest that the presence of multiple favorable environmental factors can motivate older adults to walk medium distances
The Association between Access to Public Transportation and Self-Reported Active Commuting
Djurhuus, Sune; Hansen, Henning S.; Aadahl, Mette; Glümer, Charlotte
2014-01-01
Active commuting provides routine-based regular physical activity which can reduce the risk of chronic diseases. Using public transportation involves some walking or cycling to a transit stop, transfers and a walk to the end location and users of public transportation have been found to accumulate more moderate physical activity than non-users. Understanding how public transportation characteristics are associated with active transportation is thus important from a public health perspective. This study examines the associations between objective measures of access to public transportation and self-reported active commuting. Self-reported time spent either walking or cycling commuting each day and the distance to workplace were obtained for adults aged 16 to 65 in the Danish National Health Survey 2010 (n = 28,928). Access to public transportation measures were computed by combining GIS-based road network distances from home address to public transit stops an integrating their service level. Multilevel logistic regression was used to examine the association between access to public transportation measures and active commuting. Distance to bus stop, density of bus stops, and number of transport modes were all positively associated with being an active commuter and with meeting recommendations of physical activity. No significant association was found between bus services at the nearest stop and active commuting. The results highlight the importance of including detailed measurements of access to public transit in order to identify the characteristics that facilitate the use of public transportation and active commuting. PMID:25489998
The association between access to public transportation and self-reported active commuting.
Djurhuus, Sune; Hansen, Henning S; Aadahl, Mette; Glümer, Charlotte
2014-12-05
Active commuting provides routine-based regular physical activity which can reduce the risk of chronic diseases. Using public transportation involves some walking or cycling to a transit stop, transfers and a walk to the end location and users of public transportation have been found to accumulate more moderate physical activity than non-users. Understanding how public transportation characteristics are associated with active transportation is thus important from a public health perspective. This study examines the associations between objective measures of access to public transportation and self-reported active commuting. Self-reported time spent either walking or cycling commuting each day and the distance to workplace were obtained for adults aged 16 to 65 in the Danish National Health Survey 2010 (n = 28,928). Access to public transportation measures were computed by combining GIS-based road network distances from home address to public transit stops an integrating their service level. Multilevel logistic regression was used to examine the association between access to public transportation measures and active commuting. Distance to bus stop, density of bus stops, and number of transport modes were all positively associated with being an active commuter and with meeting recommendations of physical activity. No significant association was found between bus services at the nearest stop and active commuting. The results highlight the importance of including detailed measurements of access to public transit in order to identify the characteristics that facilitate the use of public transportation and active commuting.
Field Margins, Foraging Distances and Their Impacts on Nesting Pollinator Success
Rands, Sean A.; Whitney, Heather M.
2011-01-01
The areas of wild land around the edges of agricultural fields are a vital resource for many species. These include insect pollinators, to whom field margins provide both nest sites and important resources (especially when adjacent crops are not in flower). Nesting pollinators travel relatively short distances from the nest to forage: most species of bee are known to travel less than two kilometres away. In order to ensure that these pollinators have sufficient areas of wild land within reach of their nests, agricultural landscapes need to be designed to accommodate the limited travelling distances of nesting pollinators. We used a spatially-explicit modelling approach to consider whether increasing the width of wild strips of land within the agricultural landscape will enhance the amount of wild resources available to a nesting pollinator, and if it would impact differently on pollinators with differing foraging strategies. This was done both by creating field structures with a randomised geography, and by using landscape data based upon the British agricultural landscape. These models demonstrate that enhancing field margins should lead to an increase in the availability of forage to pollinators that nest within the landscape. With the exception of species that only forage within a very short range of their nest (less than 125 m), a given amount of field margin manipulation should enhance the proportion of land available to a pollinator for foraging regardless of the distance over which it normally travels to find food. A fixed amount of field edge manipulation should therefore be equally beneficial for both longer-distance nesting foragers such as honeybees, and short-distance foragers such as solitary bees. PMID:21991390
Facilitating Distance Education.
ERIC Educational Resources Information Center
Rossman, Mark H., Ed.; Rossman, Maxine E., Ed.
1995-01-01
This collection of articles on distance learning reflects the perspectives and concerns of the learner and the facilitator of learning in distance education setting. Eight chapters are included: (1) "The Evolution and Advantages of Distance Education" (John E. Cantelon) traces the history of distance education and demonstrates how it transcends…
Role of Distance-Based Routing in Traffic Dynamics on Mobile Networks
NASA Astrophysics Data System (ADS)
Yang, Han-Xin; Wang, Wen-Xu
2013-06-01
Despite of intensive investigations on transportation dynamics taking place on complex networks with fixed structures, a deep understanding of networks consisting of mobile nodes is challenging yet, especially the lacking of insight into the effects of routing strategies on transmission efficiency. We introduce a distance-based routing strategy for networks of mobile agents toward enhancing the network throughput and the transmission efficiency. We study the transportation capacity and delivering time of data packets associated with mobility and communication ability. Interestingly, we find that the transportation capacity is optimized at moderate moving speed, which is quite different from random routing strategy. In addition, both continuous and discontinuous transitions from free flow to congestions are observed. Degree distributions are explored in order to explain the enhancement of network throughput and other observations. Our work is valuable toward understanding complex transportation dynamics and designing effective routing protocols.
Colombelli-Négrel, Diane
2016-11-01
Morphological variation between populations of the same species can arise as a response to genetic variation, local environmental conditions, or a combination of both. In this study, I examined small-scale geographic variation in bill size and body mass in little penguins ( Eudyptula minor ) across five breeding colonies in South Australia separated by <150 km. To help understand patterns driving the differences, I investigated these variations in relation to environmental parameters (air temperature, sea surface temperature, and water depth) and geographic distances between the colonies. I found substantial morphological variation among the colonies for body mass and bill measurements (except bill length). Colonies further located from each other showed greater morphological divergence overall than adjacent colonies. In addition, phenotypic traits were somewhat correlated to environmental parameters. Birds at colonies surrounded by hotter sea surface temperatures were heavier with longer and larger bills. Birds with larger and longer bills were also found at colonies surrounded by shallower waters. Overall, the results suggest that both environmental factors (natural selection) and interpopulation distances (isolation by distance) are causes of phenotypic differentiation between South Australian little penguin colonies.
Censoring distances based on labeled cortical distance maps in cortical morphometry.
Ceyhan, Elvan; Nishino, Tomoyuki; Alexopolous, Dimitrios; Todd, Richard D; Botteron, Kelly N; Miller, Michael I; Ratnanather, J Tilak
2013-01-01
It has been demonstrated that shape differences in cortical structures may be manifested in neuropsychiatric disorders. Such morphometric differences can be measured by labeled cortical distance mapping (LCDM) which characterizes the morphometry of the laminar cortical mantle of cortical structures. LCDM data consist of signed/labeled distances of gray matter (GM) voxels with respect to GM/white matter (WM) surface. Volumes and other summary measures for each subject and the pooled distances can help determine the morphometric differences between diagnostic groups, however they do not reveal all the morphometric information contained in LCDM distances. To extract more information from LCDM data, censoring of the pooled distances is introduced for each diagnostic group where the range of LCDM distances is partitioned at a fixed increment size; and at each censoring step, the distances not exceeding the censoring distance are kept. Censored LCDM distances inherit the advantages of the pooled distances but also provide information about the location of morphometric differences which cannot be obtained from the pooled distances. However, at each step, the censored distances aggregate, which might confound the results. The influence of data aggregation is investigated with an extensive Monte Carlo simulation analysis and it is demonstrated that this influence is negligible. As an illustrative example, GM of ventral medial prefrontal cortices (VMPFCs) of subjects with major depressive disorder (MDD), subjects at high risk (HR) of MDD, and healthy control (Ctrl) subjects are used. A significant reduction in laminar thickness of the VMPFC in MDD and HR subjects is observed compared to Ctrl subjects. Moreover, the GM LCDM distances (i.e., locations with respect to the GM/WM surface) for which these differences start to occur are determined. The methodology is also applicable to LCDM-based morphometric measures of other cortical structures affected by disease.
Training for Distance Teaching through Distance Learning.
ERIC Educational Resources Information Center
Cadorath, Jill; Harris, Simon; Encinas, Fatima
2002-01-01
Describes a mixed-mode bachelor degree course in English language teaching at the Universidad Autonoma de Puebla (Mexico) that was designed to help practicing teachers write appropriate distance education materials by giving them the experience of being distance students. Includes a course outline and results of a course evaluation. (Author/LRW)
Verhoeven, Hannah; Simons, Dorien; Van Dyck, Delfien; Van Cauwenberg, Jelle; Clarys, Peter; De Bourdeaudhuij, Ilse; de Geus, Bas; Vandelanotte, Corneel; Deforche, Benedicte
2016-01-01
Active transport is a convenient way to incorporate physical activity in adolescents' daily life. The present study aimed to investigate which psychosocial and environmental factors are associated with walking, cycling, public transport (train, tram, bus, metro) and passive transport (car, motorcycle, moped) over short distances (maximum eight kilometres) among older adolescents (17-18 years), to school and to other destinations. 562 older adolescents completed an online questionnaire assessing socio-demographic variables, psychosocial variables, environmental variables and transport to school/other destinations. Zero-inflated negative binomial regression models were performed. More social modelling and a higher residential density were positively associated with walking to school and walking to other destinations, respectively. Regarding cycling, higher self-efficacy and a higher social norm were positively associated with cycling to school and to other destinations. Regarding public transport, a higher social norm, more social modelling of siblings and/or friends, more social support and a higher land use mix access were positively related to public transport to school and to other destinations, whereas a greater distance to school only related positively to public transport to school. Regarding passive transport, more social support and more perceived benefits were positively associated with passive transport to school and to other destinations. Perceiving less walking and cycling facilities at school was positively related to passive transport to school only, and more social modelling was positively related to passive transport to other destinations. Overall, psychosocial variables seemed to be more important than environmental variables across the four transport modes. Social norm, social modelling and social support were the most consistent psychosocial factors which indicates that it is important to target both older adolescents and their social environment
Analytic processing of distance.
Dopkins, Stephen; Galyer, Darin
2018-01-01
How does a human observer extract from the distance between two frontal points the component corresponding to an axis of a rectangular reference frame? To find out we had participants classify pairs of small circles, varying on the horizontal and vertical axes of a computer screen, in terms of the horizontal distance between them. A response signal controlled response time. The error rate depended on the irrelevant vertical as well as the relevant horizontal distance between the test circles with the relevant distance effect being larger than the irrelevant distance effect. The results implied that the horizontal distance between the test circles was imperfectly extracted from the overall distance between them. The results supported an account, derived from the Exemplar Based Random Walk model (Nosofsky & Palmieri, 1997), under which distance classification is based on the overall distance between the test circles, with relevant distance being extracted from overall distance to the extent that the relevant and irrelevant axes are differentially weighted so as to reduce the contribution of irrelevant distance to overall distance. The results did not support an account, derived from the General Recognition Theory (Ashby & Maddox, 1994), under which distance classification is based on the relevant distance between the test circles, with the irrelevant distance effect arising because a test circle's perceived location on the relevant axis depends on its location on the irrelevant axis, and with relevant distance being extracted from overall distance to the extent that this dependency is absent. Copyright © 2017 Elsevier B.V. All rights reserved.
Electronic Data Interchange in Defense Transportation
1987-10-01
entry into a nearly paperless transportation environment. • Prescribe DoD’s use of the EDI standards developed by the transportation industry and lead...information into a format for internal use so that it can be processed. * Key Entry Costs. Data will no longer need to be entered manually into a terminal or...that commercial standards cannot meet, DoD must create standards. A vehicle for creating those DoD-unique standards now exists. That vehicle , the
Distancing, not embracing, the Distancing-Embracing model of art reception.
Davies, Stephen
2017-01-01
Despite denials in the target article, the Distancing-Embracing model appeals to compensatory ideas in explaining the appeal of artworks that elicit negative affect. The model also appeals to the deflationary effects of psychological distancing. Having pointed to the famous rejection in the 1960s of the view that aesthetic experience involves psychological distancing, I suggest that "distance" functions here as a weak metaphor that cannot sustain the explanatory burden the theory demands of it.
Long-range hot-carrier transport in hybrid perovskites visualized by ultrafast microscopy
NASA Astrophysics Data System (ADS)
Guo, Zhi; Wan, Yan; Yang, Mengjin; Snaider, Jordan; Zhu, Kai; Huang, Libai
2017-04-01
The Shockley-Queisser limit for solar cell efficiency can be overcome if hot carriers can be harvested before they thermalize. Recently, carrier cooling time up to 100 picoseconds was observed in hybrid perovskites, but it is unclear whether these long-lived hot carriers can migrate long distance for efficient collection. We report direct visualization of hot-carrier migration in methylammonium lead iodide (CH3NH3PbI3) thin films by ultrafast transient absorption microscopy, demonstrating three distinct transport regimes. Quasiballistic transport was observed to correlate with excess kinetic energy, resulting in up to 230 nanometers transport distance that could overcome grain boundaries. The nonequilibrium transport persisted over tens of picoseconds and ~600 nanometers before reaching the diffusive transport limit. These results suggest potential applications of hot-carrier devices based on hybrid perovskites.
Foundations of Distance Education. Third Edition. Routledge Studies in Distance Education.
ERIC Educational Resources Information Center
Keegan, Desmond
This text gives an overview of distance education for students, administrators, and practitioners in distance education. Chapter 1 discusses the study of distance education. Chapter 2 analyzes forms of nonconventional education (open, nontraditional) that may have similarities to distance education but are not to be identified with it. Chapter 3…
ERIC Educational Resources Information Center
Roche, Anne
2005-01-01
The author cites research from students' misconceptions of decimal notation that indicates that many students treat decimals as another whole number to the right of the decimal point. This "whole number thinking" leads some students to believe, in the context of comparing decimals, that "longer is larger" (for example, 0.45 is larger than 0.8…
Efficient Long-Range Hole Transport Through G-Quadruplexes.
Wu, Jingyuan; Meng, Zhenyu; Lu, Yunpeng; Shao, Fangwei
2017-10-09
DNA offers a means of long-range charge transport for biology and electric nanodevices. Here, a series of tetra-stranded G-quadruplexes were assembled within a dendritic DNA architecture to explore oxidative charge transport (hole transport) through the G-quadruplex. Efficient charge transport was achieved over 28 Å upon UV irradiation. Over a longer G-quadruplex bridge, hole transport was escalated to a higher efficiency, which resulted in a higher yield than that of the optimal duplex DNA for charge transport, that is, the adenine tract. Efficient long-range hole transport suggests tetra-stranded G-quadruplexes, instead of an oxidation hotspot, hold better potential as an electron conduit than duplex DNA. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Access to Transportation and Health Care Utilization in a Rural Region
ERIC Educational Resources Information Center
Arcury, Thomas A.; Preisser, John S.; Gesler, Wilbert M.; Powers, James M.
2005-01-01
Access to transportation to transverse the large distances between residences and health services in rural settings is a necessity. However, little research has examined directly access to transportation in analyses of rural health care utilization. This analysis addresses the association of transportation and health care utilization in a rural…
Point-to-point Commercial Space Transportation in the National Aviation System Final Report.
DOT National Transportation Integrated Search
2010-03-10
The advent of suborbital transport brings promise of point-to-point (PTP) long distance transportation as a revolutionary mode of air transportation. In 2008, the International Space University (ISU) of Strasbourg, France, published a report1 documen...
Solving wood chip transport problems with computer simulation.
Dennis P. Bradley; Sharon A. Winsauer
1976-01-01
Efficient chip transport operations are difficult to achieve due to frequent and often unpredictable changes in distance to market, chipping rate, time spent at the mill, and equipment costs. This paper describes a computer simulation model that allows a logger to design an efficient transport system in response to these changing factors.
NASA Astrophysics Data System (ADS)
Comer, Bryan
To study the energy and environmental impacts of emissions associated with freight transportation, the Geospatial Intermodal Freight Transport (GIFT) model was created as a joint research collaborative between the Rochester Institute of Technology (RIT) and the University of Delaware (UD). The GIFT model is a Geographic Information Systems (GIS) based model that links the U.S. and Canadian water, rail, and road transportation networks through intermodal transfer facilities to create an intermodal network. The purpose of my thesis is to apply the GIFT model to examine potential public policies related to intermodal freight transportation in the Great Lakes region of the United States. My thesis will consist of two papers. The first paper will examine the environmental, economic, and time-of-delivery tradeoffs associated with freight transportation in the Great Lakes region and examine opportunities for marine vessels to replace a portion of heavy-duty trucks for containerized freight transport. The second paper will explore the potential benefits of using the Great Lakes as a corridor for short-sea shipping as part of a longer intermodal route. The intent of my thesis is to shed light on the current issues associated with freight transport in the Great Lakes region and present public policy alternatives to address said issues. Ideally, this thesis will better inform policymakers on the impacts and tradeoffs associated with freight transportation.
Traversing psychological distance.
Liberman, Nira; Trope, Yaacov
2014-07-01
Traversing psychological distance involves going beyond direct experience, and includes planning, perspective taking, and contemplating counterfactuals. Consistent with this view, temporal, spatial, and social distances as well as hypotheticality are associated, affect each other, and are inferred from one another. Moreover, traversing all distances involves the use of abstraction, which we define as forming a belief about the substitutability for a specific purpose of subjectively distinct objects. Indeed, across many instances of both abstraction and psychological distancing, more abstract constructs are used for more distal objects. Here, we describe the implications of this relation for prediction, choice, communication, negotiation, and self-control. We ask whether traversing distance is a general mental ability and whether distance should replace expectancy in expected-utility theories. Copyright © 2014 Elsevier Ltd. All rights reserved.
Black, Jennifer M.; Zhu, Mengyang; Zhang, Pengfei; Unocic, Raymond R.; Guo, Daqiang; Okatan, M. Baris; Dai, Sheng; Cummings, Peter T.; Kalinin, Sergei V.; Feng, Guang; Balke, Nina
2016-01-01
Atomic force microscopy (AFM) force-distance measurements are used to investigate the layered ion structure of Ionic Liquids (ILs) at the mica surface. The effects of various tip properties on the measured force profiles are examined and reveal that the measured ion position is independent of tip properties, while the tip radius affects the forces required to break through the ion layers as well as the adhesion force. Force data is collected for different ILs and directly compared with interfacial ion density profiles predicted by molecular dynamics. Through this comparison it is concluded that AFM force measurements are sensitive to the position of the ion with the larger volume and mass, suggesting that ion selectivity in force-distance measurements are related to excluded volume effects and not to electrostatic or chemical interactions between ions and AFM tip. The comparison also revealed that at distances greater than 1 nm the system maintains overall electroneutrality between the AFM tip and sample, while at smaller distances other forces (e.g., van der waals interactions) dominate and electroneutrality is no longer maintained. PMID:27587276
Carrier transport dynamics in Mn-doped CdSe quantum dot sensitized solar cells
NASA Astrophysics Data System (ADS)
Poudyal, Uma; Maloney, Francis S.; Sapkota, Keshab; Wang, Wenyong
2017-10-01
In this work quantum dot sensitized solar cells (QDSSCs) were fabricated with CdSe and Mn-doped CdSe quantum dots (QDs) using the SILAR method. QDSSCs based on Mn-doped CdSe QDs exhibited improved incident photon-to-electron conversion efficiency. Carrier transport dynamics in the QDSSCs were studied using the intensity modulated photocurrent/photovoltage spectroscopy technique, from which transport and recombination time constants could be derived. Compared to CdSe QDSSCs, Mn-CdSe QDSSCs exhibited shorter transport time constant, longer recombination time constant, longer diffusion length, and higher charge collection efficiency. These observations suggested that Mn doping in CdSe QDs could benefit the performance of solar cells based on such nanostructures.
Using multiple travel paths to estimate daily travel distance in arboreal, group-living primates.
Steel, Ruth Irene
2015-01-01
Primate field studies often estimate daily travel distance (DTD) in order to estimate energy expenditure and/or test foraging hypotheses. In group-living species, the center of mass (CM) method is traditionally used to measure DTD; a point is marked at the group's perceived center of mass at a set time interval or upon each move, and the distance between consecutive points is measured and summed. However, for groups using multiple travel paths, the CM method potentially creates a central path that is shorter than the individual paths and/or traverses unused areas. These problems may compromise tests of foraging hypotheses, since distance and energy expenditure could be underestimated. To better understand the magnitude of these potential biases, I designed and tested the multiple travel paths (MTP) method, in which DTD was calculated by recording all travel paths taken by the group's members, weighting each path's distance based on its proportional use by the group, and summing the weighted distances. To compare the MTP and CM methods, DTD was calculated using both methods in three groups of Udzungwa red colobus monkeys (Procolobus gordonorum; group size 30-43) for a random sample of 30 days between May 2009 and March 2010. Compared to the CM method, the MTP method provided significantly longer estimates of DTD that were more representative of the actual distance traveled and the areas used by a group. The MTP method is more time-intensive and requires multiple observers compared to the CM method. However, it provides greater accuracy for testing ecological and foraging models.
41 CFR 302-7.102 - How is the mileage distance determined under the commuted rate method?
Code of Federal Regulations, 2010 CFR
2010-07-01
... PROPERTY 7-TRANSPORTATION AND TEMPORARY STORAGE OF HOUSEHOLD GOODS AND PROFESSIONAL BOOKS, PAPERS, AND EQUIPMENT (PBP&E) Commuted Rate § 302-7.102 How is the mileage distance determined under the commuted rate...
A Wall-Distance-Free k-ω SST Turbulence Model
NASA Astrophysics Data System (ADS)
Gleize, Vincent; Burnley, Victor
2001-11-01
In the calculation of flows around aircraft and aerodynamic bodies, the Shear-Stress Transport (SST) model by Menter has been used extensively due to its good prediction of flows with adverse pressure gradients. One main drawback of this model is the need to calculate the distance from the wall. While this is not a serious drawback for steady state calculations on non-moving grids, this calculation can become very cumbersome and expensive for unsteady simulations, especially when using unstructured grids. In this case, the wall-distance needs to be determined after each iteration. To avoid this problem, a new model is proposed which provides the benefits of the SST correction and avoids the freestream dependency of the solution, while not requiring the wall-distance. The first results for a wide range of test cases show that this model produces very good agreement with experimental data for flows with adverse pressure gradients, separation zones and shock-boundary layer interactions, closely matching the results obtained with the original SST model. This model should be very useful for unsteady calculations, such as store separation, grid adaptation, and other practical flows.
Least-cost transportation networks predict spatial interaction of invasion vectors.
Drake, D Andrew R; Mandrak, Nicholas E
2010-12-01
Human-mediated dispersal among aquatic ecosystems often results in biotic transfer between drainage basins. Such activities may circumvent biogeographic factors, with considerable ecological, evolutionary, and economic implications. However, the efficacy of predictions concerning community changes following inter-basin movements are limited, often because the dispersal mechanism is poorly understood (e.g., quantified only partially). To date, spatial-interaction models that predict the movement of humans as vectors of biotic transfer have not incorporated patterns of human movement through transportation networks. As a necessary first step to determine the role of anglers as invasion vectors across a land-lake ecosystem, we investigate their movement potential within Ontario, Canada. To determine possible model improvements resulting from inclusion of network travel, spatial-interaction models were constructed using standard Euclidean (e.g., straight-line) distance measures and also with distances derived from least-cost routing of human transportation networks. Model comparisons determined that least-cost routing both provided the most parsimonious model and also excelled at forecasting spatial interactions, with a proportion of 0.477 total movement deviance explained. The distribution of movements was characterized by many relatively short to medium travel distances (median = 292.6 km) with fewer lengthier distances (75th percentile = 484.6 km, 95th percentile = 775.2 km); however, even the shortest movements were sufficient to overcome drainage-basin boundaries. Ranking of variables in order of their contribution within the most parsimonious model determined that distance traveled, origin outflow, lake attractiveness, and sportfish richness significantly influence movement patterns. Model improvements associated with least-cost routing of human transportation networks imply that patterns of human-mediated invasion are fundamentally linked to the spatial
Brisswalter, Jeanick; Nosaka, Kazunori
2013-01-01
This review focuses on neuromuscular factors that may affect endurance performance in master athletes. During the last decade, due to the rapid increase in the number of master or veteran participants in endurance sporting competitions, many studies attempted to identify metabolic factors associated with the decrease in endurance, especially long-distance running performance with ageing, focusing on decreases in maximal oxygen consumption. However, neuromuscular factors have been less studied despite the well-known phenomena of strength loss with ageing. For master athletes to perform better in long-distance running events, it is important to reduce muscle fatigue and/or muscle damage, to improve locomotion efficiency and to facilitate recovery. To date, no consensus exists that regular endurance training is beneficial for improving locomotion efficiency, reducing muscle fatigue and muscle damage, and enhancing recovery capacity in master athletes. Some recent studies seem to indicate that master athletes have similar muscle damage to young athletes, but they require a longer recovery time after a long-distance running event. Further analyses of these parameters in master athletes require more experimental and practical interest from researchers and coaches. In particular, more attention should be directed towards the capacity to maintain muscle function with training and the role of neuromuscular factors in long-distance performance decline with ageing using a more cellular and molecular approach.
Long-range hot-carrier transport in hybrid perovskites visualized by ultrafast microscopy
Guo, Zhi; Wan, Yan; Yang, Mengjin; ...
2017-04-07
The Shockley-Queisser limit for solar cell efficiency can be overcome if hot carriers can be harvested before they thermalize. Recently, carrier cooling time up to 100 picoseconds was observed in hybrid perovskites, but it is unclear whether these long-lived hot carriers can migrate long distance for efficient collection. Here, we report direct visualization of hot-carrier migration in methylammonium lead iodide (CH 3NH 3PbI 3) thin films by ultrafast transient absorption microscopy, demonstrating three distinct transport regimes. Quasiballistic transport was observed to correlate with excess kinetic energy, resulting in up to 230 nanometers transport distance that could overcome grain boundaries. Themore » nonequilibrium transport persisted over tens of picoseconds and ~600 nanometers before reaching the diffusive transport limit. Lastly, these results suggest potential applications of hot-carrier devices based on hybrid perovskites.« less
Long-range hot-carrier transport in hybrid perovskites visualized by ultrafast microscopy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, Zhi; Wan, Yan; Yang, Mengjin
The Shockley-Queisser limit for solar cell efficiency can be overcome if hot carriers can be harvested before they thermalize. Recently, carrier cooling time up to 100 picoseconds was observed in hybrid perovskites, but it is unclear whether these long-lived hot carriers can migrate long distance for efficient collection. Here, we report direct visualization of hot-carrier migration in methylammonium lead iodide (CH 3NH 3PbI 3) thin films by ultrafast transient absorption microscopy, demonstrating three distinct transport regimes. Quasiballistic transport was observed to correlate with excess kinetic energy, resulting in up to 230 nanometers transport distance that could overcome grain boundaries. Themore » nonequilibrium transport persisted over tens of picoseconds and ~600 nanometers before reaching the diffusive transport limit. Lastly, these results suggest potential applications of hot-carrier devices based on hybrid perovskites.« less
Viral and Cellular Factors Involved in Phloem Transport of Plant Viruses
Hipper, Clémence; Brault, Véronique; Ziegler-Graff, Véronique; Revers, Frédéric
2013-01-01
Phloem transport of plant viruses is an essential step in the setting-up of a complete infection of a host plant. After an initial replication step in the first cells, viruses spread from cell-to-cell through mesophyll cells, until they reach the vasculature where they rapidly move to distant sites in order to establish the infection of the whole plant. This last step is referred to as systemic transport, or long-distance movement, and involves virus crossings through several cellular barriers: bundle sheath, vascular parenchyma, and companion cells for virus loading into sieve elements (SE). Viruses are then passively transported within the source-to-sink flow of photoassimilates and are unloaded from SE into sink tissues. However, the molecular mechanisms governing virus long-distance movement are far from being understood. While most viruses seem to move systemically as virus particles, some viruses are transported in SE as viral ribonucleoprotein complexes (RNP). The nature of the cellular and viral factors constituting these RNPs is still poorly known. The topic of this review will mainly focus on the host and viral factors that facilitate or restrict virus long-distance movement. PMID:23745125
Woodcock, James; Banister, David; Edwards, Phil; Prentice, Andrew M; Roberts, Ian
2007-09-22
We examine the links between fossil-fuel-based transportation, greenhouse-gas emissions, and health. Transport-related carbon emissions are rising and there is increasing consensus that the growth in motorised land vehicles and aviation is incompatible with averting serious climate change. The energy intensity of land transport correlates with its adverse health effects. Adverse health effects occur through climate change, road-traffic injuries, physical inactivity, urban air pollution, energy-related conflict, and environmental degradation. For the world's poor people, walking is the main mode of transport, but such populations often experience the most from the harms of energy-intensive transport. New energy sources and improvements in vehicle design and in information technology are necessary but not sufficient to reduce transport-related carbon emissions without accompanying behavioural change. By contrast, active transport has the potential to improve health and equity, and reduce emissions. Cities require safe and pleasant environments for active transport with destinations in easy reach and, for longer journeys, public transport that is powered by renewable energy, thus providing high levels of accessibility without car use. Much investment in major road projects does not meet the transport needs of poor people, especially women whose trips are primarily local and off road. Sustainable development is better promoted through improving walking and cycling infrastructures, increasing access to cycles, and investment in transport services for essential needs. Our model of London shows how increased active transport could help achieve substantial reductions in emissions by 2030 while improving population health. There exists the potential for a global contraction and convergence in use of fossil-fuel energy for transport to benefit health and achieve sustainability.
[A New Distance Metric between Different Stellar Spectra: the Residual Distribution Distance].
Liu, Jie; Pan, Jing-chang; Luo, A-li; Wei, Peng; Liu, Meng
2015-12-01
Distance metric is an important issue for the spectroscopic survey data processing, which defines a calculation method of the distance between two different spectra. Based on this, the classification, clustering, parameter measurement and outlier data mining of spectral data can be carried out. Therefore, the distance measurement method has some effect on the performance of the classification, clustering, parameter measurement and outlier data mining. With the development of large-scale stellar spectral sky surveys, how to define more efficient distance metric on stellar spectra has become a very important issue in the spectral data processing. Based on this problem and fully considering of the characteristics and data features of the stellar spectra, a new distance measurement method of stellar spectra named Residual Distribution Distance is proposed. While using this method to measure the distance, the two spectra are firstly scaled and then the standard deviation of the residual is used the distance. Different from the traditional distance metric calculation methods of stellar spectra, when used to calculate the distance between stellar spectra, this method normalize the two spectra to the same scale, and then calculate the residual corresponding to the same wavelength, and the standard error of the residual spectrum is used as the distance measure. The distance measurement method can be used for stellar classification, clustering and stellar atmospheric physical parameters measurement and so on. This paper takes stellar subcategory classification as an example to test the distance measure method. The results show that the distance defined by the proposed method is more effective to describe the gap between different types of spectra in the classification than other methods, which can be well applied in other related applications. At the same time, this paper also studies the effect of the signal to noise ratio (SNR) on the performance of the proposed method
Spin qubit transport in a double quantum dot
NASA Astrophysics Data System (ADS)
Zhao, Xinyu; Hu, Xuedong
Long distance spin communication is a crucial ingredient to scalable quantum computer architectures based on electron spin qubits. One way to transfer spin information over a long distance on chip is via electron transport. Here we study the transport of an electron spin qubit in a double quantum dot by tuning the interdot detuning voltage. We identify a parameter regime where spin relaxation hot-spots can be avoided and high-fidelity spin transport is possible. Within this parameter space, the spin transfer fidelity is determined by the operation speed and the applied magnetic field. In particular, near zero detuning, a proper choice of operation speed is essential to high fidelity. In addition, we also investigate the modification of the effective g-factor by the interdot detuning, which could lead to a phase error between spin up and down states. The results presented in this work could be a useful guidance for experimentally achieving high-fidelity spin qubit transport. We thank financial support by US ARO via Grant W911NF1210609.
Distance Education and Distance Learning: Some Psychological Considerations.
ERIC Educational Resources Information Center
Cropley, Arthur J.; Kahl, Thomas N.
1983-01-01
Compares and contrasts distance education and face-to-face education in terms of selected psychological dimensions, i.e., organization and learning, motivation, learning and communication processes, didactic activities and materials, and evaluation and feedback. Psychological aspects of distance education that may be favorable to learning are also…
14 CFR 151.95 - Fences; distance markers; navigational and landing aids; and offsite work.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Fences; distance markers; navigational and landing aids; and offsite work. 151.95 Section 151.95 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRPORTS FEDERAL AID TO AIRPORTS Project Programming...
Impact of urban built environment on urban short-distance taxi travel: the case of Shanghai
NASA Astrophysics Data System (ADS)
Wu, Zhuoye; Zhuo, Jian
2018-05-01
The excessive individual motorized transport is the main cause of urban congestion and generates negative consequences on urban environmental quality, energy consumption, infrastructure supply and urban security. Bicycle can compete effectively with automobile for short-distance travels within 3km. If we take action to encourage the rider to shift from automobile to bike for the short-distance travels, it leaves us a great chance to reduce the modal share of individual motorized mode. This paper focus on the spatial impact of built environment on short-distance taxi riders’ travel behaviour. The data sources include taxi trajectory data for a week, demographic data of the Sixth National Census, POI data. In this paper, we figure out the volumes and spatial distribution of short-distance taxi travel in the central city of Shanghai. We build a multiple regression model to quantitative analyze the impact of urban built environment on urban short-distance taxi travel. The findings explain the spatial distribution short-distance taxi travel. In the conclusion, some advice are provided on how planners change the spatial settings to discourage short-distance individual motorized travel.
Happy orang-utans live longer lives.
Weiss, Alexander; Adams, Mark J; King, James E
2011-12-23
Nonhuman primate ageing resembles its human counterpart. Moreover, ratings of subjective well-being traits in chimpanzees, orang-utans and rhesus macaques are similar to those of humans: they are intercorrelated, heritable, and phenotypically and genetically related to personality. We examined whether, as in humans, orang-utan subjective well-being was related to longer life. The sample included 184 zoo-housed orang-utans followed up for approximately 7 years. Age, sex, species and number of transfers were available for all subjects and 172 subjects were rated on at least one item of a subjective well-being scale. Of the 31 orang-utans that died, 25 died a mean of 3.4 years after being rated. Even in a model that included, and therefore, statistically adjusted for, sex, age, species and transfers, orang-utans rated as being "happier" lived longer. The risk differential between orang-utans that were one standard deviation above and one standard deviation below baseline in subjective well-being was comparable with approximately 11 years in age. This finding suggests that impressions of the subjective well-being of captive great apes are valid indicators of their welfare and longevity.
Facilitating longer working lives: international evidence on why and how.
Wise, David A
2010-01-01
The article advances the view that social and economic choices in societies can reasonably adjust as the age structure of the population changes; in particular, some of the bounty of longer lives can reasonably be allocated to prolonging the labor force participation of older workers. Data on reductions in mortality and, in some countries, declines in disability are presented in ways that help to clarify that prolonged working lives may be a natural concomitant of living longer. The article reviews the problems inherent in the combination of living longer and reducing labor force participation at older ages. It discusses two ways to facilitate longer working lives: (1) eliminating penalties on work at older ages--inherent in the provisions of the social security programs in many countries--that induce older persons to leave the labor force at younger ages; and (2) correcting a false rationale--the "boxed economy" view of the labor market--that is often used to support retention of the provisions that induce older persons to leave the labor force.
From synapse to nucleus and back again--communication over distance within neurons.
Fainzilber, Mike; Budnik, Vivian; Segal, Rosalind A; Kreutz, Michael R
2011-11-09
How do neurons integrate intracellular communication from synapse to nucleus and back? Here we briefly summarize aspects of this topic covered by a symposium at Neuroscience 2011. A rich repertoire of signaling mechanisms link both dendritic terminals and axon tips with neuronal soma and nucleus, using motor-dependent transport machineries to traverse the long intracellular distances along neuronal processes. Activation mechanisms at terminals include localized translation of dendritic or axonal RNA, proteolytic cleavage of receptors or second messengers, and differential phosphorylation of signaling moieties. Signaling complexes may be transported in endosomes, or as non-endosomal complexes associated with importins and dynein. Anterograde transport of RNA granules from the soma to neuronal processes, coupled with retrograde transport of proteins translated locally at terminals or within processes, may fuel ongoing bidirectional communication between soma and synapse to modulate synaptic plasticity as well as neuronal growth and survival decisions.
Distance to nearest road in the conterminous United States
Watts, Raymond D.
2005-01-01
The new dataset is the first member of the National Overview Road Metrics (NORM) family of road related indicators. This indicator measures straight-line or Euclidean distance (ED) to the nearest road, and is given the compound name NORM ED. NORM ED data can be viewed and downloaded from the transportation section of the web viewer for The National Map, http://nationalmap.usgs.gov. The full-resolution dataset for the conterminous states is made of 8.7 billion values.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Separation distance requirements for co-location of division 1.1 and 1.3 explosives with liquid propellants. 420.69 Section 420.69 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Separation distance requirements for co-location of division 1.1 and 1.3 explosives with liquid propellants. 420.69 Section 420.69 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...
Energy transport velocity in bidispersed magnetic colloids.
Bhatt, Hem; Patel, Rajesh; Mehta, R V
2012-07-01
Study of energy transport velocity of light is an effective background for slow, fast, and diffuse light and exhibits the photonic property of the material. We report a theoretical analysis of magnetic field dependent resonant behavior in forward-backward anisotropy factor, light diffusion constant, and energy transport velocity for bidispersed magnetic colloids. A bidispersed magnetic colloid is composed of micrometer size magnetic spheres dispersed in a magnetic nanofluid consisting of magnetic nanoparticles in a nonmagnetic liquid carrier. Magnetic Mie resonances and reduction in energy transport velocity accounts for the possible delay (longer dwell time) by field dependent resonant light transport. This resonant behavior of light in bidispersed magnetic colloids suggests a novel magnetophotonic material.
Factors of bacteria and virus transport in groundwater
NASA Astrophysics Data System (ADS)
Pekdeger, A.; Matthess, G.
1983-06-01
The underground transport of pathogenic bacteria and viruses may be described by the general transport equation considering dispersion, adsorption, and biological elimination. The survival time of bacteria and viruses in groundwater is different for the specific species and for the specific groundwater environment. Dispersion causes a distribution of pollutants in time and space, thus their concentration decreases over time and with transport distance. Microorganisms are reversibly adsorbed on underground particles, which causes a retardation of their transport velocity with respect to groundwater flow velocity. An additional approach is provided by the filter theory.
Open and Distance Learning Today. Routledge Studies in Distance Education Series.
ERIC Educational Resources Information Center
Lockwood, Fred, Ed.
This book contains the following papers on open and distance learning today: "Preface" (Daniel); "Big Bang Theory in Distance Education" (Hawkridge); "Practical Agenda for Theorists of Distance Education" (Perraton); "Trends, Directions and Needs: A View from Developing Countries" (Koul); "American…
NASA Astrophysics Data System (ADS)
Tarigan, U.; Sidabutar, R. F.; Tarigan, U. P. P.; Chen, A.
2018-04-01
Manufacturers engaged in the business, producing CPO and kernels whose raw materials are oil palm fresh fruit bunches taken from their own plantation, generally face problems of transporting from plantation to factory where there is often a change of distance traveled by the truck the carrier of FFB is due to non-specific transport instructions. The research was conducted to determine the optimal transportation route in terms of distance, time and route number. The determination of this transportation route is solved using Nearest Neighbours and Clarke & Wright Savings methods. Based on the calculations performed then found in area I with method Nearest Neighbours has a distance of 200.78 Km while Clarke & Wright Savings as with a result of 214.09 Km. As for the harvest area, II obtained results with Nearest Neighbours method of 264.37 Km and Clarke & Wright Savings method with a total distance of 264.33 Km. Based on the calculation of the time to do all the activities of transporting FFB juxtaposed with the work time of the driver got the reduction of conveyance from 8 units to 5 units. There is also improvement of fuel efficiency by 0.8%.
ERIC Educational Resources Information Center
Whittington, M. Susie, Ed.; And Others
1994-01-01
Includes "Next Best Thing to Being There" (Whittington); "Taking the Distance out of Distance Education" (Miller, King); "Preparing a Course for Distance Delivery" (Newcomb); "Team Teaching via Two-Way Interactive Video" (Nichols, Trout); "Using the Ag Ed Network" (Peal); "Student's Perspective" (Schoellhorn); "Need for Instruction in Agriculture…
Transportation and General Traffic Management, Change 2
NASA Technical Reports Server (NTRS)
1979-01-01
This Handbook sets forth those transportation and general traffic management responsibilities, guidelines, and procedures governing the use of commercial and Government transportation for NASA. Transportation is an integral function of the logistic process, involving all activities incident to the movement of persons and things. The fundamental and continuous objectives of transportation are to control and diminish the time-distance of lines of communication by the most suitable means. The function of transportation is accomplished through, and encompasses all, the planning, direction, supervision, and execution of the technical, operational, and administrative tasks required to procure or furnish efficient and economical conveyance of cargo and personnel by all modes of commercial and Government transportation. This Handbook is applicable to NASA Headquarters and Field Installations.
Verhoeven, Hannah; Simons, Dorien; Van Dyck, Delfien; Van Cauwenberg, Jelle; Clarys, Peter; De Bourdeaudhuij, Ilse; de Geus, Bas; Vandelanotte, Corneel; Deforche, Benedicte
2016-01-01
Background Active transport is a convenient way to incorporate physical activity in adolescents’ daily life. The present study aimed to investigate which psychosocial and environmental factors are associated with walking, cycling, public transport (train, tram, bus, metro) and passive transport (car, motorcycle, moped) over short distances (maximum eight kilometres) among older adolescents (17–18 years), to school and to other destinations. Methods 562 older adolescents completed an online questionnaire assessing socio-demographic variables, psychosocial variables, environmental variables and transport to school/other destinations. Zero-inflated negative binomial regression models were performed. Results More social modelling and a higher residential density were positively associated with walking to school and walking to other destinations, respectively. Regarding cycling, higher self-efficacy and a higher social norm were positively associated with cycling to school and to other destinations. Regarding public transport, a higher social norm, more social modelling of siblings and/or friends, more social support and a higher land use mix access were positively related to public transport to school and to other destinations, whereas a greater distance to school only related positively to public transport to school. Regarding passive transport, more social support and more perceived benefits were positively associated with passive transport to school and to other destinations. Perceiving less walking and cycling facilities at school was positively related to passive transport to school only, and more social modelling was positively related to passive transport to other destinations. Conclusions Overall, psychosocial variables seemed to be more important than environmental variables across the four transport modes. Social norm, social modelling and social support were the most consistent psychosocial factors which indicates that it is important to target both
NASA Astrophysics Data System (ADS)
Markwitz, V.; Kirkland, C. L.; Mehnert, A.; Gessner, K.; Shaw, J.
2017-12-01
Detrital zircon studies can suffer from selective loss of provenance information due to U-Pb age discordance, metamictization, metamorphic overprinting and fluviatile transport processes. The relationship between isotopic composition and zircon grain shape, and how grain shape is modified during transport, is largely unknown. We combine X-ray tomography with U-Pb geochronology to quantify how fluvial transport affects 3-D zircon shape, detrital age signature, and grain density along the Murchison River, whose catchment comprises Eoarchean to Early Paleozoic source rocks in Western Australia. We acquired tomographic volumes and isotopic data from 373 detrital zircons to document changes in size, shape and density in transport direction, and explore how grain shape, age spectra and the proportion of discordant material vary along the channel. Results show that shape characteristics are sensitive to transport distance, stream gradient, proximity to source material, and whether the source consists of primary or recycled zircons. With increasing transport distance, grain lengths decrease more than their widths. Furthermore, the loss of metamict grains occurs at a near constant rate, resulting in a linear increase of mean calculated zircon density by ca. 0.03 g/cm3 per 100 km transport distance. 3-D grain shape is therefore strongly linked to detrital age signature, and mean grain density is a function of the absolute transport distance. 3-D shape characteristics provide valuable information on detrital zircon populations, including the interaction between source materials with fluvial transport processes, which significantly affects preservation bias and, by inference, the representativeness of the sampled data.
From a distance: implications of spontaneous self-distancing for adaptive self-reflection.
Ayduk, Ozlem; Kross, Ethan
2010-05-01
Although recent experimental work indicates that self-distancing facilitates adaptive self-reflection, it remains unclear (a) whether spontaneous self-distancing leads to similar adaptive outcomes, (b) how spontaneous self-distancing relates to avoidance, and (c) how this strategy impacts interpersonal behavior. Three studies examined these issues demonstrating that the more participants spontaneously self-distanced while reflecting on negative memories, the less emotional (Studies 1-3) and cardiovascular (Study 2) reactivity they displayed in the short term. Spontaneous self-distancing was also associated with lower emotional reactivity and intrusive ideation over time (Study 1). The negative association between spontaneous self-distancing and emotional reactivity was mediated by how participants construed their experience (i.e., less recounting relative to reconstruing) rather than avoidance (Studies 1-2). In addition, spontaneous self-distancing was associated with more problem-solving behavior and less reciprocation of negativity during conflicts among couples in ongoing relationships (Study 3). Although spontaneous self-distancing was empirically related to trait rumination, it explained unique variance in predicting key outcomes. 2010 APA, all rights reserved
From a distance: Implications of spontaneous self-distancing for adaptive self-reflection
Ayduk, Özlem; Kross, Ethan
2010-01-01
Although recent work experimental work indicates that self-distancing facilitates adaptive self-reflection, it remains unclear (a) whether spontaneously self-distancing leads to similar adaptive outcomes, (b) how spontaneous self-distancing relates to avoidance, and (c) how this strategy impacts interpersonal behavior. Three studies examined these issues demonstrating that the more participants spontaneously self-distanced while reflecting on negative memories, the less emotional (Studies 1–3) and cardiovascular (Study 2) reactivity they displayed in the short-term. Spontaneous self-distancing was also associated with lower emotional reactivity and intrusive ideation over time (Study 1). The negative association between spontaneous self-distancing and emotional reactivity was mediated by how participants construed their experience (i.e., less recounting relative to reconstruing) rather than avoidance (Studies 1–2). In addition, spontaneous self-distancing was associated with more problem-solving behavior and less reciprocation of negativity during conflicts among couples in ongoing relationships (Study 3). Although spontaneous self-distancing was empirically related to trait rumination, it explained unique variance in predicting key outcomes. PMID:20438226
Coarse sediment transport dynamics at three spatial scales of bedrock channel bed complexity
NASA Astrophysics Data System (ADS)
Goode, J. R.; Wohl, E.
2007-12-01
Rivers incised into bedrock in fold-dominated terrain display a complex bed topography that strongly interacts with local hydraulics to produce spatial differences in bed sediment flux. We used painted tracer clasts to investigate how this complex bed topography influences coarse sediment transport at three spatial scales (reach, cross- section and grain). The study was conducted along the Ocoee River gorge, Tennessee between the TVA Ocoee #3 dam and the 1996 Olympic whitewater course. The bed topography consists of undulating bedrock ribs, which are formed at a consistent strike to the bedding and cleavage of the metagreywake and phyllite substrate. Ribs vary in their orientation to flow (from parallel to oblique) and amplitude among three study reaches. These bedrock ribs create a rough bed topography that substantially alters the local flow field and influences reach- scale roughness. In each reach, 300 tracer clasts were randomly selected from the existing bed material. Tracer clasts were surveyed and transport distances were calculated after five scheduled summer releases and a suite of slightly larger but sporadic winter releases. Transport distances were examined as a function of rib orientation and amplitude (reach scale), spatial proximity to bedrock ribs and standard deviation of the bed elevation (cross- section scale), and whether clasts were hydraulically shielded by surrounding clasts, incorporated in the armour layer, imbricated, and/or existed in a pothole, in addition to size and angularity. At the reach scale, where ribs are parallel to flow, lower reach-scale roughness leads to greater sediment transport capacity, sediment flux and transport distances because transport is uninhibited in the downstream direction. Preliminary results indicate that cross section scale characteristics of bed topography exert a greater control on transport distances than grain size.
NASA Astrophysics Data System (ADS)
Chen, Xingxin; Wu, Zhonghan; Cai, Qipeng; Cao, Wei
2018-04-01
It is well established that seismic waves traveling through porous media stimulate fluid flow and accelerate particle transport. However, the mechanism remains poorly understood. To quantify the coupling effect of hydrodynamic force, transportation distance, and ultrasonic stimulation on particle transport and fate in porous media, laboratory experiments were conducted using custom-built ultrasonic-controlled soil column equipment. Three column lengths (23 cm, 33 cm, and 43 cm) were selected to examine the influence of transportation distance. Transport experiments were performed with 0 W, 600 W, 1000 W, 1400 W, and 1800 W of applied ultrasound, and flow rates of 0.065 cm/s, 0.130 cm/s, and 0.195 cm/s, to establish the roles of ultrasonic stimulation and hydrodynamic force. The laboratory results suggest that whilst ultrasonic stimulation does inhibit suspended-particle deposition and accelerate deposited-particle release, both hydrodynamic force and transportation distance are the principal controlling factors. The median particle diameter for the peak concentration was approximately 50% of that retained in the soil column. Simulated particle-breakthrough curves using extended traditional filtration theory effectively described the experimental curves, particularly the curves that exhibited a higher tailing concentration.
Wasfi, Rania A; Ross, Nancy A; El-Geneidy, Ahmed M
2013-09-01
This paper estimates the amount of daily walking associated with using public transportation in a large metropolitan area and examines individual and contextual characteristics associated with walking distances. Total walking distance to and from transit was calculated from a travel diary survey for 6913 individuals. Multilevel regression modelling was used to examine the underlying factors associated with walking to public transportation. The physical activity benefits of public transportation varied along gender and socio-economic lines. Recommended minutes of daily physical activity can be achieved for public transportation users, especially train users living in affluent suburbs. Copyright © 2013 Elsevier Ltd. All rights reserved.
Vafeiadi, Marina; Agramunt, Silvia; Papadopoulou, Eleni; Besselink, Harrie; Mathianaki, Kleopatra; Karakosta, Polyxeni; Spanaki, Ariana; Koutis, Antonis; Chatzi, Leda; Vrijheid, Martine; Kogevinas, Manolis
2013-01-01
Anogenital distance in animals is used as a measure of fetal androgen action. Prenatal exposure to dioxins and dioxin-like compounds in rodents causes reproductive changes in male offspring and decreases anogenital distance. We assessed whether in utero exposure to dioxins and dioxin-like compounds adversely influences anogenital distance in newborns and young children (median age, 16 months; range, 1-31 months). We measured anogenital distance among participants of the "Rhea" mother-child cohort study in Crete and the Hospital del Mar (HMAR) cohort in Barcelona. Anogenital distance (AGD; anus to upper penis), anoscrotal distance (ASD; anus to scrotum), and penis width (PW) were measured in 119 newborn and 239 young boys; anoclitoral (ACD; anus to clitoris) and anofourchetal distance (AFD; anus to fourchette) were measured in 118 newborn and 223 young girls. We estimated plasma dioxin-like activity in maternal blood samples collected at delivery with the Dioxin-Responsive Chemically Activated LUciferase eXpression (DR CALUX®) bioassay. Anogenital distances were sexually dimorphic, being longer in males than females. Plasma dioxin-like activity was negatively associated with AGD in male newborns. The estimated change in AGD per 10 pg CALUX®-toxic equivalent/g lipid increase was -0.44 mm (95% CI: -0.80, -0.08) after adjusting for confounders. Negative but smaller and nonsignificant associations were observed for AGD in young boys. No associations were found in girls. Male infants may be susceptible to endocrine-disrupting effects of dioxins. Our findings are consistent with the experimental animal evidence used by the Food and Agriculture Organization/World Health Organization to set recommendations for human dioxin intake.
Vafeiadi, Marina; Agramunt, Silvia; Papadopoulou, Eleni; Besselink, Harrie; Mathianaki, Kleopatra; Karakosta, Polyxeni; Spanaki, Ariana; Koutis, Antonis; Chatzi, Leda; Vrijheid, Martine
2012-01-01
Background: Anogenital distance in animals is used as a measure of fetal androgen action. Prenatal exposure to dioxins and dioxin-like compounds in rodents causes reproductive changes in male offspring and decreases anogenital distance. Objective: We assessed whether in utero exposure to dioxins and dioxin-like compounds adversely influences anogenital distance in newborns and young children (median age, 16 months; range, 1–31 months). Methods: We measured anogenital distance among participants of the “Rhea” mother–child cohort study in Crete and the Hospital del Mar (HMAR) cohort in Barcelona. Anogenital distance (AGD; anus to upper penis), anoscrotal distance (ASD; anus to scrotum), and penis width (PW) were measured in 119 newborn and 239 young boys; anoclitoral (ACD; anus to clitoris) and anofourchetal distance (AFD; anus to fourchette) were measured in 118 newborn and 223 young girls. We estimated plasma dioxin-like activity in maternal blood samples collected at delivery with the Dioxin-Responsive Chemically Activated LUciferase eXpression (DR CALUX®) bioassay. Results: Anogenital distances were sexually dimorphic, being longer in males than females. Plasma dioxin-like activity was negatively associated with AGD in male newborns. The estimated change in AGD per 10 pg CALUX®–toxic equivalent/g lipid increase was –0.44 mm (95% CI: –0.80, –0.08) after adjusting for confounders. Negative but smaller and nonsignificant associations were observed for AGD in young boys. No associations were found in girls. Conclusions: Male infants may be susceptible to endocrine-disrupting effects of dioxins. Our findings are consistent with the experimental animal evidence used by the Food and Agriculture Organization/World Health Organization to set recommendations for human dioxin intake. PMID:23171674
NASA Astrophysics Data System (ADS)
Dorow, C. J.; Hasling, M. W.; Calman, E. V.; Butov, L. V.; Wilkes, J.; Campman, K. L.; Gossard, A. C.
2017-06-01
We present the direct measurements of magnetoexciton transport. Excitons give the opportunity to realize the high magnetic-field regime for composite bosons with magnetic fields of a few tesla. Long lifetimes of indirect excitons allow the study of kinetics of magnetoexciton transport with time-resolved optical imaging of exciton photoluminescence. We performed spatially, spectrally, and time-resolved optical imaging of transport of indirect excitons in high magnetic fields. We observed that an increasing magnetic field slows down magnetoexciton transport. The time-resolved measurements of the magnetoexciton transport distance allowed for an experimental estimation of the magnetoexciton diffusion coefficient. An enhancement of the exciton photoluminescence energy at the laser excitation spot was found to anticorrelate with the exciton transport distance. A theoretical model of indirect magnetoexciton transport is presented and is in agreement with the experimental data.
Hierarchical traits distances explain grassland Fabaceae species' ecological niches distances.
Fort, Florian; Jouany, Claire; Cruz, Pablo
2015-01-01
Fabaceae species play a key role in ecosystem functioning through their capacity to fix atmospheric nitrogen via their symbiosis with Rhizobium bacteria. To increase benefits of using Fabaceae in agricultural systems, it is necessary to find ways to evaluate species or genotypes having potential adaptations to sub-optimal growth conditions. We evaluated the relevance of phylogenetic distance, absolute trait distance and hierarchical trait distance for comparing the adaptation of 13 grassland Fabaceae species to different habitats, i.e., ecological niches. We measured a wide range of functional traits (root traits, leaf traits, and whole plant traits) in these species. Species phylogenetic and ecological distances were assessed from a species-level phylogenetic tree and species' ecological indicator values, respectively. We demonstrated that differences in ecological niches between grassland Fabaceae species were related more to their hierarchical trait distances than to their phylogenetic distances. We showed that grassland Fabaceae functional traits tend to converge among species with the same ecological requirements. Species with acquisitive root strategies (thin roots, shallow root systems) are competitive species adapted to non-stressful meadows, while conservative ones (coarse roots, deep root systems) are able to tolerate stressful continental climates. In contrast, acquisitive species appeared to be able to tolerate low soil-P availability, while conservative ones need high P availability. Finally we highlight that traits converge along the ecological gradient, providing the assumption that species with similar root-trait values are better able to coexist, regardless of their phylogenetic distance.
Hierarchical traits distances explain grassland Fabaceae species' ecological niches distances
Fort, Florian; Jouany, Claire; Cruz, Pablo
2015-01-01
Fabaceae species play a key role in ecosystem functioning through their capacity to fix atmospheric nitrogen via their symbiosis with Rhizobium bacteria. To increase benefits of using Fabaceae in agricultural systems, it is necessary to find ways to evaluate species or genotypes having potential adaptations to sub-optimal growth conditions. We evaluated the relevance of phylogenetic distance, absolute trait distance and hierarchical trait distance for comparing the adaptation of 13 grassland Fabaceae species to different habitats, i.e., ecological niches. We measured a wide range of functional traits (root traits, leaf traits, and whole plant traits) in these species. Species phylogenetic and ecological distances were assessed from a species-level phylogenetic tree and species' ecological indicator values, respectively. We demonstrated that differences in ecological niches between grassland Fabaceae species were related more to their hierarchical trait distances than to their phylogenetic distances. We showed that grassland Fabaceae functional traits tend to converge among species with the same ecological requirements. Species with acquisitive root strategies (thin roots, shallow root systems) are competitive species adapted to non-stressful meadows, while conservative ones (coarse roots, deep root systems) are able to tolerate stressful continental climates. In contrast, acquisitive species appeared to be able to tolerate low soil-P availability, while conservative ones need high P availability. Finally we highlight that traits converge along the ecological gradient, providing the assumption that species with similar root-trait values are better able to coexist, regardless of their phylogenetic distance. PMID:25741353
Distance Education: A Consumer's Guide. What Distance Learners Need To Know.
ERIC Educational Resources Information Center
Western Interstate Commission for Higher Education, Boulder, CO. Western Cooperative for Educational Communications.
This pamphlet is intended to assist the consumer in making informed decisions when choosing between distance learning programs. Distance education and distance learners are defined. Included is advice on beginning a program search; choosing a school; accreditation; evaluating quality of electronically offered programs; evaluate non-accredited…
Poethke, Hans Joachim; Gros, Andreas; Hovestadt, Thomas
2011-08-07
We analyze the simultaneous evolution of emigration and settlement decisions for actively dispersing species differing in their ability to assess population density. Using an individual-based model we simulate dispersal as a multi-step (patch to patch) movement in a world consisting of habitat patches surrounded by a hostile matrix. Each such step is associated with the same mortality risk. Our simulations show that individuals following an informed strategy, where emigration (and settlement) probability depends on local population density, evolve a lower (natal) emigration propensity but disperse over significantly larger distances - i.e. postpone settlement longer - than individuals performing density-independent emigration. This holds especially when variation in environmental conditions is spatially correlated. Both effects can be traced to the informed individuals' ability to better exploit existing heterogeneity in reproductive chances. Yet, already moderate distance-dependent dispersal costs prevent the evolution of multi-step (long-distance) dispersal, irrespective of the dispersal strategy. Copyright © 2011 Elsevier Ltd. All rights reserved.
[Health risks of long-distance air travel. Role of the general practitioner].
Bazex, Jacques; Cabanis, Emmanuel Alain
2010-06-01
Air transport is seeing an increase in long-distance flights (12-16 hours average flight time), greater seating capacity, and a higher proportion of elderly, and hence more fragile, passengers. The French Academy of Medicine recommends that medical care be reinforced, particularly on long-distance flights, through the following measures: (i) passengers should be informed in advance of potential risks, through a Passenger's Guide, (ii) all future passengers should be encouraged to seek health advice and information from their general practitioner, (iii) flight crew members should receive training as "in-flight medical correspondents", and (iv) airlines and plane designers should reserve a "medical space" on the plane, equipped with appropriate medical materials.
Spacecraft Fire Detection: Smoke Properties and Transport in Low-Gravity
NASA Technical Reports Server (NTRS)
Urban, David L.; Ruff, Gary A.; Brooker, John E.; Cleary, Thomas; Yang, Jiann; Mulholland, George; Yuan, Zeng-guang
2007-01-01
Results from a recent smoke particle size measurement experiment conducted on the International Space Station (ISS) are presented along with the results from a model of the transport of smoke in the ISS. The experimental results show that, for the materials tested, a substantial portion of the smoke particles are below 500 nm in diameter. The smoke transport model demonstrated that mixing dominates the smoke transport and that consequently detection times are longer than in normal gravity.
Wang, Joon Ho; Kato, Yuki; Ingham, Sheila J M; Maeyama, Akira; Linde-Rosen, Monica; Smolinski, Patrick; Fu, Freddie H
2012-10-01
The aim of this study was to determine the end-to-end distance changes in anterior cruciate ligament (ACL) fibers during flexion/extension and internal/external rotation of the knee. The positional relation between the femur and tibia of 10 knees was digitized on a robotic system during flexion/extension and with an internal/external rotational torque (5 Nm). The ACL insertion site data, acquired by 3-dimensional scanning, were superimposed on the positional data. The end-to-end distances of 5 representative points on the femoral and tibial insertion sites of the ACL were calculated. The end-to-end distances of all representative points except the most anterior points were longest at full extension and shortest at 90°. The distances of the anteromedial (AM) and posterolateral (PL) bundles were 37.2 ± 2.1 mm and 27.5 ± 2.8 mm, respectively, at full extension and 34.7 ± 2.4 mm and 20.7 ± 2.3 mm, respectively, at 90°. Only 4 knees had an isometric point, which was 1 of the 3 anterior points. Under an internal torque, both bundles became longer with statistical meaning at all flexion angles (P = .005). The end-to-end distances of all points became longest with internal torque at full extension and shortest with an external torque at 90°. Only 4 of 10 specimens had an isometric point at a variable anterior point. The end-to-end distances of the AM and PL bundles were longer in extension and shorter in flexion. The nonisometric tendency of the ACL and the end-to-end distance change during knee flexion/extension and internal/external rotation should be considered during ACL reconstruction to avoid overconstraint of the graft. Copyright © 2012 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
An eCertificate Program in Transportation Planning
DOT National Transportation Integrated Search
2012-08-01
In this project, researchers developed a proposal to extend the delivery of the recently developed : Graduate Certificate in Transportation Planning at Texas A&M University (TAMU) to a wider audience via : distance education (online or eCertificate)....
Taï chimpanzees anticipate revisiting high-valued fruit trees from further distances.
Ban, Simone D; Boesch, Christophe; Janmaat, Karline R L
2014-11-01
The use of spatio-temporal memory has been argued to increase food-finding efficiency in rainforest primates. However, the exact content of this memory is poorly known to date. This study investigated what specific information from previous feeding visits chimpanzees (Pan troglodytes verus), in Taï National Park, Côte d'Ivoire, take into account when they revisit the same feeding trees. By following five adult females for many consecutive days, we tested from what distance the females directed their travels towards previously visited feeding trees and how previous feeding experiences and fruit tree properties influenced this distance. To exclude the influence of sensory cues, the females' approach distance was measured from their last significant change in travel direction until the moment they entered the tree's maximum detection field. We found that chimpanzees travelled longer distances to trees at which they had previously made food grunts and had rejected fewer fruits compared to other trees. In addition, the results suggest that the chimpanzees were able to anticipate the amount of fruit that they would find in the trees. Overall, our findings are consistent with the hypothesis that chimpanzees act upon a retrieved memory of their last feeding experiences long before they revisit feeding trees, which would indicate a daily use of long-term prospective memory. Further, the results are consistent with the possibility that positive emotional experiences help to trigger prospective memory retrieval in forest areas that are further away and have fewer cues associated with revisited feeding trees.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Black, Jennifer M.; Zhu, Mengyang; Zhang, Pengfei
In this paper, atomic force microscopy (AFM) force-distance measurements are used to investigate the layered ion structure of Ionic Liquids (ILs) at the mica surface. The effects of various tip properties on the measured force profiles are examined and reveal that the measured ion position is independent of tip properties, while the tip radius affects the forces required to break through the ion layers as well as the adhesion force. Force data is collected for different ILs and directly compared with interfacial ion density profiles predicted by molecular dynamics. Through this comparison it is concluded that AFM force measurements aremore » sensitive to the position of the ion with the larger volume and mass, suggesting that ion selectivity in force-distance measurements are related to excluded volume effects and not to electrostatic or chemical interactions between ions and AFM tip. Finally, the comparison also revealed that at distances greater than 1 nm the system maintains overall electroneutrality between the AFM tip and sample, while at smaller distances other forces (e.g., van der waals interactions) dominate and electroneutrality is no longer maintained.« less
Black, Jennifer M.; Zhu, Mengyang; Zhang, Pengfei; ...
2016-09-02
In this paper, atomic force microscopy (AFM) force-distance measurements are used to investigate the layered ion structure of Ionic Liquids (ILs) at the mica surface. The effects of various tip properties on the measured force profiles are examined and reveal that the measured ion position is independent of tip properties, while the tip radius affects the forces required to break through the ion layers as well as the adhesion force. Force data is collected for different ILs and directly compared with interfacial ion density profiles predicted by molecular dynamics. Through this comparison it is concluded that AFM force measurements aremore » sensitive to the position of the ion with the larger volume and mass, suggesting that ion selectivity in force-distance measurements are related to excluded volume effects and not to electrostatic or chemical interactions between ions and AFM tip. Finally, the comparison also revealed that at distances greater than 1 nm the system maintains overall electroneutrality between the AFM tip and sample, while at smaller distances other forces (e.g., van der waals interactions) dominate and electroneutrality is no longer maintained.« less
Transport of microplastics by two collembolan species.
Maaß, Stefanie; Daphi, Daniel; Lehmann, Anika; Rillig, Matthias C
2017-06-01
Plastics, despite their great benefits, have become a ubiquitous environmental pollutant, with microplastic particles having come into focus most recently. Microplastic effects have been intensely studied in aquatic, especially marine systems; however, there is lack of studies focusing on effects on soil and its biota. A basic question is if and how surface-deposited microplastic particles are transported into the soil. We here wished to test if soil microarthropods, using Collembola, can transport these particles over distances of centimeters within days in a highly controlled experimental set-up. We conducted a fully factorial experiment with two collembolan species of differing body size, Folsomia candida and Proisotoma minuta, in combination with urea-formaldehyde particles of two different particle sizes. We observed significant differences between the species concerning the distance the particles were transported. F. candida was able to transport larger particles further and faster than P. minuta. Using video, we observed F. candida interacting with urea-formaldehyde particles and polyethylene terephthalate fibers, showing translocation of both material types. Our data clearly show that microplastic particles can be moved and distributed by soil microarthropods. Although we did not observe feeding, it is possible that microarthropods contribute to the accumulation of microplastics in the soil food web. Copyright © 2017 Elsevier Ltd. All rights reserved.
Long-distance dispersal of plants by vehicles as a driver of plant invasions.
von der Lippe, Moritz; Kowarik, Ingo
2007-08-01
Roadsides are preferential migration corridors for invasive plant species and can act as starting points for plant invasions into adjacent habitats. Rapid spread and interrupted distribution patterns of introduced plant species indicate long-distance dispersal along roads. The extent to which this process is due to species' migration along linear habitats or, alternatively, to seed transport by vehicles has not yet been tested systematically. We tested this by sampling seeds inside long motorway tunnels to exclude nontraffic dispersal. Vehicles transported large amounts of seeds. The annual seed rain caused by vehicles on the roadsides of five different tunnel lanes within three tunnels along a single urban motorway in Berlin, Germany, ranged from 635 to 1579 seeds/m(2)/year. Seeds of non-native species accounted for 50.0% of the 204 species and 54.4% of the total 11,818 seeds trapped inside the tunnels. Among the samples were 39 (19.1%) highly invasive species that exhibit detrimental effects on native biodiversity in some parts of the world. By comparing the flora in the tunnel with that adjacent to the tunnel entrances we confirmed long-distance dispersal events (>250 m) for 32.3% of the sampled species. Seed sources in a radius of 100 m around the entrances of the tunnels had no significant effect on species richness and species composition of seed samples from inside the tunnels, indicating a strong effect of long-distance dispersal by vehicles. Consistently, the species composition of the tunnel seeds was more similar to the regional roadside flora of Berlin than to the local flora around the tunnel entrances. Long-distance dispersal occurred significantly more frequently in seeds of non-native (mean share 38.5%) than native species (mean share 4.1%). Our results showed that long-distance dispersal by vehicles was a routine rather than an occasional mechanism. Dispersal of plants by vehicles will thus accelerate plant invasions and induce rapid changes in
Visualization and modeling of smoke transport over landscape scales
Glenn P. Forney; William Mell
2007-01-01
Computational tools have been developed at the National Institute of Standards and Technology (NIST) for modeling fire spread and smoke transport. These tools have been adapted to address fire scenarios that occur in the wildland urban interface (WUI) over kilometer-scale distances. These models include the smoke plume transport model ALOFT (A Large Open Fire plume...
NASA Astrophysics Data System (ADS)
Sévellec, Florian; Fedorov, Alexey V.
2016-09-01
Oceanic northward heat transport is commonly assumed to be positively correlated with the Atlantic meridional overturning circulation (AMOC). For example, in numerical "water-hosing" experiments, imposing anomalous freshwater fluxes in the northern Atlantic leads to a slow-down of the AMOC and the corresponding reduction of oceanic northward heat transport. Here, we study the sensitivity of the ocean heat and volume transports to surface heat and freshwater fluxes using a generalized stability analysis. For the sensitivity to surface freshwater fluxes, we find that, while the direct relationship between the AMOC volume and heat transports holds on shorter time scales, it can reverse on timescales longer than 500 years or so. That is, depending on the model surface boundary conditions, reduction in the AMOC volume transport can potentially lead to a stronger heat transport on long timescales, resulting from the gradual increase in ocean thermal stratification. We discuss the implications of these results for the problem of steady state (statistical equilibrium) in ocean and climate GCM as well as paleoclimate problems including millennial climate variability.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sevellec, Florian; Fedorov, Alexey V.
Oceanic northward heat transport is commonly assumed to be positively correlated with the Atlantic meridional overturning circulation (AMOC). For example, in numerical "water-hosing" experiments, imposing anomalous freshwater fluxes in the northern Atlantic leads to a slow-down of the AMOC and the corresponding reduction of oceanic northward heat transport. Here, we study the sensitivity of the ocean heat and volume transports to surface heat and freshwater fluxes using a generalized stability analysis. For the sensitivity to surface freshwater fluxes, we find that, while the direct relationship between the AMOC volume and heat transports holds on shorter time scales, it can reversemore » on timescales longer than 500 years or so. That is, depending on the model surface boundary conditions, reduction in the AMOC volume transport can potentially lead to a stronger heat transport on long timescales, resulting from the gradual increase in ocean thermal stratification. Finally, we discuss the implications of these results for the problem of steady state (statistical equilibrium) in ocean and climate GCM as well as paleoclimate problems including millennial climate variability.« less
Sevellec, Florian; Fedorov, Alexey V.
2016-01-04
Oceanic northward heat transport is commonly assumed to be positively correlated with the Atlantic meridional overturning circulation (AMOC). For example, in numerical "water-hosing" experiments, imposing anomalous freshwater fluxes in the northern Atlantic leads to a slow-down of the AMOC and the corresponding reduction of oceanic northward heat transport. Here, we study the sensitivity of the ocean heat and volume transports to surface heat and freshwater fluxes using a generalized stability analysis. For the sensitivity to surface freshwater fluxes, we find that, while the direct relationship between the AMOC volume and heat transports holds on shorter time scales, it can reversemore » on timescales longer than 500 years or so. That is, depending on the model surface boundary conditions, reduction in the AMOC volume transport can potentially lead to a stronger heat transport on long timescales, resulting from the gradual increase in ocean thermal stratification. Finally, we discuss the implications of these results for the problem of steady state (statistical equilibrium) in ocean and climate GCM as well as paleoclimate problems including millennial climate variability.« less
North Dakota wheat transportation knowledge for market enhancement.
DOT National Transportation Integrated Search
2010-07-01
North Dakota wheat producers are located long distances from major consumer and export markets. Understanding the competitive position of their products is important to focusing efforts for market development and transportation investments. Research ...
Sexual dimorphism in the human face assessed by euclidean distance matrix analysis.
Ferrario, V F; Sforza, C; Pizzini, G; Vogel, G; Miani, A
1993-01-01
The form of any object can be viewed as a combination of size and shape. A recently proposed method (euclidean distance matrix analysis) can differentiate between size and shape differences. It has been applied to analyse the sexual dimorphism in facial form in a sample of 108 healthy young adults (57 men, 51 women). The face was wider and longer in men than in women. A global shape difference was demonstrated, the male face being more rectangular and the female face more square. Gender variations involved especially the lower third of the face and, in particular, the position of the pogonion relative to the other structures. PMID:8300436
Taraska, Justin W.; Puljung, Michael C.; Zagotta, William N.
2009-01-01
The structure and dynamics of proteins underlies the workings of virtually every biological process. Existing biophysical methods are inadequate to measure protein structure at atomic resolution, on a rapid time scale, with limited amounts of protein, and in the context of a cell or membrane. FRET can measure distances between two probes, but depends on the orientation of the probes and typically works only over long distances comparable with the size of many proteins. Also, common probes used for FRET can be large and have long, flexible attachment linkers that position dyes far from the protein backbone. Here, we improve and extend a fluorescence method called transition metal ion FRET that uses energy transfer to transition metal ions as a reporter of short-range distances in proteins with little orientation dependence. This method uses a very small cysteine-reactive dye monobromobimane, with virtually no linker, and various transition metal ions bound close to the peptide backbone as the acceptor. We show that, unlike larger fluorophores and longer linkers, this donor–acceptor pair accurately reports short-range distances and changes in backbone distances. We further extend the method by using cysteine-reactive metal chelators, which allow the technique to be used in protein regions of unknown secondary structure or when native metal ion binding sites are present. This improved method overcomes several of the key limitations of classical FRET for intramolecular distance measurements. PMID:19805285
Khera, Nandita; Gooley, Ted; Flowers, Mary E D; Sandmaier, Brenda M; Loberiza, Fausto; Lee, Stephanie J; Appelbaum, Frederick
2016-07-01
Regionalization of specialized health services can deliver high-quality care but may have an adverse impact on access and outcomes because of distance from the regional centers. In the case of hematopoietic cell transplantation (HCT), the effect of increased distance between the transplantation center and the rural/urban residence is unclear because of conflicting results from the existing studies. We examined the association between distance from primary residence to the transplantation center and rural versus urban residence with clinical outcomes after allogeneic HCT in a large cohort of patients. Overall mortality (OM), nonrelapse mortality (NRM), and relapse in all patients and those who survived for 200 days after HCT were assessed in 2849 patients who received their first allogeneic HCT between 2000 and 2010 at Fred Hutchinson Cancer Research Center (FHCRC)/Seattle Cancer Care Alliance. Median distance from FHCRC was 263 miles (range, 0 to 2740 miles) and 83% of patients were urban residents. The association between distance and the hazard of OM varied according to conditioning intensity: myeloablative (MA) versus nonmyeloablative (NMA). Among MA patients, there was no evidence of an increased risk of mortality with increased distance, but for NMA patients, the results did show a suggestion of increased risk of mortality for some distances, although globally the difference was not statistically significant. In the subgroup of patients who survived 200 days, there was no evidence that the risks of OM, relapse, or NRM were increased with increasing distance. We did not find any association between longer distance from transplantation center and urban/rural residence and outcomes after MA HCT. In patients undergoing NMA transplantations, this relationship and how it is influenced by factors such as age, payers, and comorbidities needs to be further investigated. Copyright © 2016 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc
Massarweh, Nader N; Chiang, Yi-Ju; Xing, Yan; Chang, George J; Haynes, Alex B; You, Y Nancy; Feig, Barry W; Cormier, Janice N
2014-03-20
Health care access and advanced cancer stage are associated with oncologic outcomes for numerous common cancers. However, the impact of patient travel distance to health care on stage at diagnosis has not been well characterized. This study used a historical cohort of patients with colon cancer in the National Cancer Data Base from 2003 through 2010. The primary outcome, stage at diagnosis, was evaluated using hierarchical regression modeling. A secondary outcome was time to receipt of initial therapy that was evaluated using Cox shared frailty modeling. Among 296,474 patients with colon cancer (mean age, 68 ± 13.6 years; 47.6% male; 78.5% white), 3.9% traveled ≥ 50 miles to the diagnosing facility. Fewer black patients, patients with higher income, and patients with lower education traveled longer distances (trend test P < .001 for all). Patients traveling ≥ 50 miles were more likely to present with metastatic disease compared with those traveling less than 12.5 miles (odds ratio [OR], 1.18; 95% CI, 1.12 to 1.24) or 12.5 to 49.9 miles (OR, 1.18; 95% CI, 1.12 to 1.24). In sensitivity analyses, the association was robust to alternate methods of modeling travel distance (quintile stratification or continuous). Travel distance ≥ 50 miles was also associated with a higher likelihood of earlier initiation of therapy compared with travel distance of less than 12.5 miles (hazard ratio [HR], 1.10; 95% CI, 1.08 to 1.13) or 12.5 to 49.9 miles (HR, 1.11; 95% CI, 1.08 to 1.13). Advanced colon cancer stage at diagnosis is associated with patient travel distance to health care, which may be a barrier to early cancer screening. Health care reform efforts designed to address only insurance coverage may not mitigate disparities based on difficulties accessing cancer care.
Minimization of municipal solid waste transportation route in West Jakarta using Tabu Search method
NASA Astrophysics Data System (ADS)
Chaerul, M.; Mulananda, A. M.
2018-04-01
Indonesia still adopts the concept of collect-haul-dispose for municipal solid waste handling and it leads to the queue of the waste trucks at final disposal site (TPA). The study aims to minimize the total distance of waste transportation system by applying a Transshipment model. In this case, analogous of transshipment point is a compaction facility (SPA). Small capacity of trucks collects the waste from waste temporary collection points (TPS) to the compaction facility which located near the waste generator. After compacted, the waste is transported using big capacity of trucks to the final disposal site which is located far away from city. Problem related with the waste transportation can be solved using Vehicle Routing Problem (VRP). In this study, the shortest distance of route from truck pool to TPS, TPS to SPA, and SPA to TPA was determined by using meta-heuristic methods, namely Tabu Search 2 Phases. TPS studied is the container type with total 43 units throughout the West Jakarta City with 38 units of Armroll truck with capacity of 10 m3 each. The result determines the assignment of each truck from the pool to the selected TPS, SPA and TPA with the total minimum distance of 2,675.3 KM. The minimum distance causing the total cost for waste transportation to be spent by the government also becomes minimal.
Lifelong Learning & Distance Higher Education. Perspectives on Distance Education
ERIC Educational Resources Information Center
McIntosh, Christopher, Ed.
2005-01-01
Reflecting a common objective of ensuring quality Education for All, this book is a joint initiative of UNESCO and COL and jointly published. Lifelong Learning in Distance Higher Education brings together a diverse group of experts from many countries. The book provides a clear picture of the challenges, problems and potential of distance higher…
The travel-time ellipse: An approximate zone of transport
Almendinger, J.E.
1994-01-01
A zone of transport for a well is defined as the area in the horizontal plane bounded by a contour of equal ground-water travel time to the well. For short distances and ground-water travel times near a well, the potentiometric surface may be simulated analytically as that for a fully penetrating well in a uniform flow field. The zone of transport for this configuration is nearly elliptical. A simple method is derived to calculate a travel-time ellipse that approximates the zone of transport for a well in a uniform flow field. The travel-time ellipse was nearly congruent with the exact solution for the theoretical zone of transport for ground-water travel times of at least 10 years and for aquifer property values appropriate for southeastern Minnesota. For distances and travel times approaching infinity, however, the ellipse becomes slightly wider at its midpoint and narrower near its upgradient boundary than the theoretical zone of transport. The travel-time ellipse also may be used to simulate the plume area surrounding an injection well. However, the travel-time ellipse is an approximation that does not account for the effect of dispersion in enlarging the true area of an injection plume or zone of transport; hence, caution is advised in the use and interpretation of this simple construction.
The Longer School Day and Five Term Year in CTCs: Some Initial Observations.
ERIC Educational Resources Information Center
Hagedorn, Julia
To satisfy the requirements of the British national curriculum and to provide greater emphasis on the teaching of mathematics, science, and technology, city technical colleges (CTCs) have adopted a longer working week and, in several cases, a longer school year. This document examines outcomes of the longer school day and the five-term year, 4…
Topological Distances Between Brain Networks
Lee, Hyekyoung; Solo, Victor; Davidson, Richard J.; Pollak, Seth D.
2018-01-01
Many existing brain network distances are based on matrix norms. The element-wise differences may fail to capture underlying topological differences. Further, matrix norms are sensitive to outliers. A few extreme edge weights may severely affect the distance. Thus it is necessary to develop network distances that recognize topology. In this paper, we introduce Gromov-Hausdorff (GH) and Kolmogorov-Smirnov (KS) distances. GH-distance is often used in persistent homology based brain network models. The superior performance of KS-distance is contrasted against matrix norms and GH-distance in random network simulations with the ground truths. The KS-distance is then applied in characterizing the multimodal MRI and DTI study of maltreated children.
Long-distance signalling in plant defence.
Heil, Martin; Ton, Jurriaan
2008-06-01
Plants use inducible defence mechanisms to fend off harmful organisms. Resistance that is induced in response to local attack is often expressed systemically, that is, in organs that are not yet damaged. In the search for translocated defence signals, biochemical studies follow the physical movement of putative signals, and grafting experiments use mutants that are impaired in the production or perception of these signals. Long-distance signals can directly activate defence or can prime for the stronger and faster induction of defence. Historically, research has focused on the vascular transport of signalling metabolites, but volatiles can play a crucial role as well. We compare the advantages and constraints of vascular and airborne signals for the plant, and discuss how they can act in synergy to achieve optimised resistance in distal plant parts.
Correlates of Trail Use for Recreation and Transportation on 5 Massachusetts Trails.
Orstad, Stephanie L; McDonough, Meghan H; Klenosky, David B; Mattson, Marifran; Troped, Philip J
2016-08-01
Promoting use of community trails is a recommended strategy for increasing population levels of physical activity. Correlates of walking and cycling for recreation or transportation differ, though few studies have compared correlates of trail-based physical activity for recreation and transportation purposes. This study examined associations of demographic, social, and perceived built environmental factors with trail use for recreation and transportation and whether associations were moderated by age, gender, and prior trail use. Adults (N = 1195) using 1 of 5 trails in Massachusetts responded to an intercept survey. We used multiple linear and logistic regression models to examine associations with trail use. Respondents' mean age was 44.9 years (standard deviation = 12.5), 55.3% were female, and 82.0% were white. Age (longer-term users only), trail use with others, travel time to the trail, and trail design were significantly associated with use for recreation (P < .05). Age, gender, trail safety (longer-term users only), travel time to the trail, trail design (younger users only), and trail beauty were associated with use for transportation (P < .05). Some common correlates were found for recreational and transportation trail use, whereas some variables were uniquely associated with use for 1 purpose. Tailored strategies are suggested to promote trail use for recreation and transportation.
NASA Astrophysics Data System (ADS)
Hotchkiss, E. R.; Ziegler, S. E.; Edwards, K. A.; Bowering, K.
2017-12-01
Water acts as a control on the cycling of organic carbon (OC). Forest productivity responses to climate change are linked to water availability while water residence time is a major control on OC loss in aquatic ecosystems. However, controls on the export of terrestrial OC to the aquatic environment remains poorly understood. Transport of dissolved OC (DOC) through soils both vertically to deeper soil horizons and into aquatic systems is a key flux of terrestrial OC, but the climate drivers controlling OC mobilized from soils is poorly understood. We installed zero-tension lysimeters across similar balsam fir forest sites within three regions that span a MAT gradient of 5.2˚C and MAP of 1050-1500 mm. Using soil water collected over all seasons for four years we tested whether a warmer and wetter climate promotes greater DOC fluxes in ecosystems experiencing relatively high precipitation. Variability within and between years was compared to that observed across climates to test the sensitivity of this flux to shorter relative to longer-term climate effects on this flux. The warmest and wettest southern site exhibited the greatest annual DOC flux (25 to 28 g C m-2 y-1) in contrast to the most northern site (8 to 10 g C m -2 y-1). This flux represented 10% of litterfall C inputs across sites and surpassed the DOC export from associated forested headwater streams (1 to 16 g C m-2 y-1) suggesting terrestrial to aquatic interface processing. Historical climate and increased soil C inputs explain the greater DOC flux in the southern region. Even in years with comparable annual precipitation among regions the DOC flux differed by climate region. Furthermore, neither quantity nor form of precipitation could explain inter-annual differences in DOC flux within each region. Region specific relationships between precipitation and soil water flux instead suggest historical climate effects may impact soil water transport efficiency thereby controlling the regional variation in
The Cost of Distance Education. IEC Broadsheets on Distance Learning No. 17.
ERIC Educational Resources Information Center
Perraton, Hilary
One of a series offering practical advice and information on distance teaching, this broadsheet first looks at the reasons for trying to measure distance teaching costs and the methodological and economic difficulties involved in such measurements. Broadcasting and print costs in distance teaching are discussed, and evidence about the costs of…
Liberman, Nira; Förster, Jens
2009-08-01
In 4 studies, the authors examined the prediction derived from construal level theory (CLT) that higher level of perceptual construal would enhance estimated egocentric psychological distance. The authors primed participants with global perception, local perception, or both (the control condition). Relative to the control condition, global processing made participants estimate larger psychological distances in time (Study 1), space (Study 2), social distance (Study 3), and hypotheticality (Study 4). Local processing had the opposite effect. Consistent with CLT, all studies show that the effect of global-versus-local processing did emerge when participants estimated egocentric distances, which are distances from the experienced self in the here and now, but did not emerge with temporal distances not from now (Study 1), spatial distances not from here (Study 2), social distances not from the self (Study 3), or hypothetical events that did not involve altering an experienced reality (Study 4).
Implications of longer term rest from grazing in the sagebrush steppe
K.W. Davies; M. Vavra; B. Schultz; N. Rimbey
2014-01-01
Longer term grazing rest has occurred or been proposed in large portions of the sagebrush steppe based on the assumption that it will improve ecosystem properties. However, information regarding the influence of longer term rest from grazing is limited and has not been summarized. We synthesized the scientific literature on long-term rest in the sagebrush steppe to...
The value of public transportation for improving the quality of life for the rural elderly.
DOT National Transportation Integrated Search
2012-07-01
Transportation for the rural elderly is an increasing concern as baby boomers age and young people continue to exit rural communities. As the elderly are no longer able to drive themselves, they rely on alternate forms of transportation, including pu...
Distance learning perspectives.
Pandza, Haris; Masic, Izet
2013-01-01
The development of modern technology and the Internet has enabled the explosive growth of distance learning. distance learning is a process that is increasingly present in the world. This is the field of education focused on educating students who are not physically present in the traditional classrooms or student's campus. described as a process where the source of information is separated from the students in space and time. If there are situations that require the physical presence of students, such as when a student is required to physically attend the exam, this is called a hybrid form of distance learning. This technology is increasingly used worldwide. The Internet has become the main communication channel for the development of distance learning.
Tatineni, Satyanarayana; Wosula, Everlyne N; Bartels, Melissa; Hein, Gary L; Graybosch, Robert A
2016-09-01
Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TriMV) are economically important viral pathogens of wheat. Wheat cvs. Mace, carrying the Wsm1 gene, is resistant to WSMV and TriMV, and Snowmass, with Wsm2, is resistant to WSMV. Viral resistance in both cultivars is temperature sensitive and is effective at 18°C or below but not at higher temperatures. The underlying mechanisms of viral resistance of Wsm1 and Wsm2, nonallelic single dominant genes, are not known. In this study, we found that fluorescent protein-tagged WSMV and TriMV elicited foci that were approximately similar in number and size at 18 and 24°C, on inoculated leaves of resistant and susceptible wheat cultivars. These data suggest that resistant wheat cultivars at 18°C facilitated efficient cell-to-cell movement. Additionally, WSMV and TriMV efficiently replicated in inoculated leaves of resistant wheat cultivars at 18°C but failed to establish systemic infection, suggesting that Wsm1- and Wsm2-mediated resistance debilitated viral long-distance transport. Furthermore, we found that neither virus was able to enter the leaf sheaths of inoculated leaves or crowns of resistant wheat cultivars at 18°C but both were able to do so at 24°C. Thus, wheat cvs. Mace and Snowmass provide resistance at the long-distance movement stage by specifically blocking virus entry into the vasculature. Taken together, these data suggest that both Wsm1 and Wsm2 genes similarly confer virus resistance by temperature-dependent impairment of viral long-distance movement.
Formation of virions is strictly required for turnip yellows virus long-distance movement in plants.
Hipper, Clémence; Monsion, Baptiste; Bortolamiol-Bécet, Diane; Ziegler-Graff, Véronique; Brault, Véronique
2014-02-01
Viral genomic RNA of the Turnip yellows virus (TuYV; genus Polerovirus; family Luteoviridae) is protected in virions formed by the major capsid protein (CP) and the minor component, the readthrough (RT*) protein. Long-distance transport, used commonly by viruses to systemically infect host plants, occurs in phloem sieve elements and two viral forms of transport have been described: virions and ribonucleoprotein (RNP) complexes. With regard to poleroviruses, virions have always been presumed to be the long-distance transport form, but the potential role of RNP complexes has not been investigated. Here, we examined the requirement of virions for polerovirus systemic movement by analysing CP-targeted mutants that were unable to form viral particles. We confirmed that TuYV mutants that cannot encapsidate into virions are not able to reach systemic leaves. To completely discard the possibility that the introduced mutations in CP simply blocked the formation or the movement of RNP complexes, we tested in trans complementation of TuYV CP mutants by providing WT CP expressed in transgenic plants. WT CP was able to facilitate systemic movement of TuYV CP mutants and this observation was always correlated with the formation of virions. This demonstrated clearly that virus particles are essential for polerovirus systemic movement.
NASA Astrophysics Data System (ADS)
Pye, Kenneth; Blott, Simon J.
2016-08-01
An important question for coastal management concerns the importance of individual storms and clusters of storms on longer term beach sediment budgets, beach and dune erosion, and coastal flood risk. Between October 2013 and March 2014 a series of deep Atlantic low pressure systems crossed the Northeast Atlantic, and strong winds, high waves and high water levels affected many coastal areas in the UK and other parts of western Europe. Net dune recession of up to 12.1 m occurred around Formby Point. On 5 December 2013 the highest water level ever recorded at Liverpool (6.22 m ODN) coincided with waves of Hs of 4.55 m and Tp of 9.3 s in Liverpool Bay. Wave trimming of the dune toe occurred along the entire length of the Sefton coast, but significant dune erosion occurred only where the upper beach (between the mean high water spring tide level and the dune toe) was < 25 m wide. Sediment budget calculations based on LiDAR surveys in October 2013 and May 2014 indicated a net loss of 127 × 103 m3 of sediment from the beach (above 0 m ODN) and a loss of 268 × 103 m3 from the frontal dune system, mostly at Formby Point. However, some parts of the beach to the south of Formby Point gained sediment, indicating net north to south transport over the winter. When considered in a longer term context, the 2013-14 winter represents only a small perturbation on the longer-term coast trend of erosion at Formby Point and progradation to the north and south. Analysis of LiDAR data over a longer time period 1999-2014 indicated upper beach and dune sediment loss of 780 × 103 m3 from the north-central part of Formby Point, with net gains of 806 × 103 m3 and 2116 × 103 m3 in areas to the north and south, respectively. This indicates a net onshore transport of 2142 × 103 m3 from Liverpool Bay towards the coast between Birkdale and Altcar, with a further net total of 210 × 103 m3 transported towards the shore between Altcar and Crosby. In view of the demonstrated value of airborne
Adaptation and Promotion of Emergency Medical Service Transportation for Climate Change
Pan, Chih-Long; Chiu, Chun-Wen; Wen, Jet-Chau
2014-01-01
Abstract The purpose of this study is to find a proper prehospital transportation scenario planning of an emergency medical service (EMS) system for possible burdensome casualties resulting from extreme climate events. This project focuses on one of the worst natural catastrophic events in Taiwan, the 88 Wind-caused Disasters, caused by the Typhoon Morakot; the case of the EMS transportation in the Xiaolin village is reviewed and analyzed. The sequential-conveyance method is designed to promote the efficiency of all the ambulance services related to transportation time and distance. Initially, a proposed mobile emergency medical center (MEMC) is constructed in a safe location near the area of the disaster. The ambulances are classified into 2 categories: the first-line ambulances, which reciprocate between the MEMC and the disaster area to save time and shorten the working distances and the second-line ambulances, which transfer patients in critical condition from the MEMC to the requested hospitals for further treatment. According to the results, the sequential-conveyance method is more efficient than the conventional method for EMS transportation in a mass-casualty incident (MCI). This method improves the time efficiency by 52.15% and the distance efficiency by 56.02%. This case study concentrates on Xiaolin, a mountain village, which was heavily destroyed by a devastating mudslide during the Typhoon Morakot. The sequential-conveyance method for the EMS transportation in this research is not only more advantageous but also more rational in adaptation to climate change. Therefore, the findings are also important to all the decision-making with respect to a promoted EMS transportation, especially in an MCI. PMID:25501065
Adaptation and promotion of emergency medical service transportation for climate change.
Pan, Chih-Long; Chiu, Chun-Wen; Wen, Jet-Chau
2014-12-01
The purpose of this study is to find a proper prehospital transportation scenario planning of an emergency medical service (EMS) system for possible burdensome casualties resulting from extreme climate events. This project focuses on one of the worst natural catastrophic events in Taiwan, the 88 Wind-caused Disasters, caused by the Typhoon Morakot; the case of the EMS transportation in the Xiaolin village is reviewed and analyzed. The sequential-conveyance method is designed to promote the efficiency of all the ambulance services related to transportation time and distance. Initially, a proposed mobile emergency medical center (MEMC) is constructed in a safe location near the area of the disaster. The ambulances are classified into 2 categories: the first-line ambulances, which reciprocate between the MEMC and the disaster area to save time and shorten the working distances and the second-line ambulances, which transfer patients in critical condition from the MEMC to the requested hospitals for further treatment. According to the results, the sequential-conveyance method is more efficient than the conventional method for EMS transportation in a mass-casualty incident (MCI). This method improves the time efficiency by 52.15% and the distance efficiency by 56.02%. This case study concentrates on Xiaolin, a mountain village, which was heavily destroyed by a devastating mudslide during the Typhoon Morakot. The sequential-conveyance method for the EMS transportation in this research is not only more advantageous but also more rational in adaptation to climate change. Therefore, the findings are also important to all the decision-making with respect to a promoted EMS transportation, especially in an MCI.
NASA Astrophysics Data System (ADS)
Mihaela, Istrate; Alexandru, Boroiu; Viorel, Nicolae; Ionel, Vieru
2017-10-01
One of the major problems facing the Pitesti city is the road congestion that occurs in the central area of the city during the peak hours. With all the measures taken in recent years - the widening of road arteries, increasing the number of parking spaces, the creation of overground road passages - it is obvious that the problem can only be solved by a new philosophy regarding urban mobility: it is no longer possible to continue through solutions to increase the accessibility of the central area of the city, but it is necessary, on the contrary, to promote a policy of discouraging the penetration of vehicles in the city center, coupled with a policy of improving the connection between urban public transport and county public transport. This new approach is also proposed in the new Urban Mobility Plan of Pitesti city, under development. The most convincing argument for the necessity of this new orientation in the Pitesti city mobility plan is based on the analysis of the current situation of passenger transport on the territory of Pitesti city: the analysis of “public transport versus private transport” reveals a very low occupancy rate for cars and the fact that the road surface required for a passenger (the dynamic area) is much higher in the case of private transport than in the case of public transport. Measurements of passenger flows and vehicle flows on the 6 penetration ways in the city have been made and the calculations clearly demonstrate the benefits of an urban public transport system connected by “transshipment buses” to be made at the edge of the city, to the county public transport system. In terms of inter-county transport, it will continue to be connected to the urban public transport system by existing bus Station, within the city: South Bus Station and North Bus Station. The usefulness of the paper is that it identifies the solutions for sustainable mobility in Pitesti city and proposes concrete solutions for the development of the
Determining Usability Versus Cost and Yields of a Regional Transport
NASA Technical Reports Server (NTRS)
Gvozdenovic, Slobodan
1999-01-01
Regional transports are designed to operate on air networks having the basic characteristics of short trip distances and low density passengers/cargo, i.e. small numbers of passengers per flight. Regional transports passenger capacity is from 10 to 100 seats and operate on routes from 350 to 1000 nautical miles (nm). In order to meet passenger requirements providing low fares and high or required number of frequencies, airlines must constantly monitor operational costs and keep them low. It is obvious that costs of operating aircraft must be lower than yield obtained by transporting passengers and cargo. The requirement to achieve favorable yield/cost ratio must provide the answer to the question of which aircraft will best meet a specific air network (Simpson, 1972). An air network is defined by the number of services, the trip distance of each service, and the number of flights (frequencies) per day and week.
Transportation cost of anticoagulation clinic visits in an urban setting.
Hwang, Jamie M; Clemente, Jennifer; Sharma, Krishna P; Taylor, Thomas N; Garwood, Candice L
2011-10-01
Patients being managed on warfarin make frequent or regular visits to anticoagulation monitoring appointments. International studies have evaluated transportation cost and associated time related to anticoagulation clinic visits. To our knowledge, no studies have evaluated the cost of transportation to such clinic visits in the United States. To describe the methods of transportation and estimate the average total cost of transportation to and from an anticoagulation clinic in an urban setting. We prospectively conducted a survey of patients treated at the Harper Anticoagulation Clinic located in Detroit, Michigan, during November 2010. The survey was given to patients while waiting at their regularly scheduled clinic appointments and included questions regarding mode of transportation, distance traveled in miles, parking payment, and time missed from work for clinic appointments. The mean distance traveled was translated into cost assuming 50 cents per mile based on 2010 estimates by the Internal Revenue Service. Sixty patients responded to the 11-item survey; response rates for individual items varied because participants were instructed to skip questions that did not pertain to them. Of the 47 participants responding to demographic questions, 70.2% were female, and 46.8% were older than 60 years. Transportation by private vehicle (80.0%), either driven by patients (41.7%) or someone else (38.3%), was the most common method reported. Use of private automobile translated into a cost of $11.19 per round trip. Other means of transportation identified include a ride from a medical transportation service (10.0%), bus (5.0%), walking (3.3%), and taxi (1.7%). The mean (SD) distance traveled to the clinic for all methods of transportation was 8.34 (7.7) miles. We estimated the average cost of round-trip transportation to be $10.78 weighted for all transportation modes. This is a direct nonmedical cost that is paid for by most patients out of pocket. However, 9 of 44 (20
NASA Astrophysics Data System (ADS)
Arnold, Luc
2013-07-01
I compare three methods for transmitting signals over interstellar distances: radio transmitters, lasers and artificial transits. The quantitative comparison is based on physical quantities depending on energy cost and transmitting time L, the last parameter in the Drake equation. With our assumptions, radio transmitters are the most energy-effective, while macro-engineered planetary-sized objects producing artificial transits seem effective on the long term to transmit an attention-getting signal for a time that might be much longer than the lifetime of the civilization that produced the artefact.
Adaptive Feedback in Local Coordinates for Real-time Vision-Based Motion Control Over Long Distances
NASA Astrophysics Data System (ADS)
Aref, M. M.; Astola, P.; Vihonen, J.; Tabus, I.; Ghabcheloo, R.; Mattila, J.
2018-03-01
We studied the differences in noise-effects, depth-correlated behavior of sensors, and errors caused by mapping between coordinate systems in robotic applications of machine vision. In particular, the highly range-dependent noise densities for semi-unknown object detection were considered. An equation is proposed to adapt estimation rules to dramatic changes of noise over longer distances. This algorithm also benefits the smooth feedback of wheels to overcome variable latencies of visual perception feedback. Experimental evaluation of the integrated system is presented with/without the algorithm to highlight its effectiveness.
Applications to determine the shortest tower BTS distance using Dijkstra algorithm
NASA Astrophysics Data System (ADS)
Mardana, Herwin; Maharani, Septya; Hatta, Heliza Rahmania
2017-02-01
Telecommunications Tower or so-called BTS (Base Transceiver System) Toweris one of the main components in the network infrastructure that has experienced an increase in the number of construction. Telecommunications tower function as a place to put the antenna signal transmitter (access network) to provide communication services to customers around the tower. In addition, other use of telecommunications tower also to place the transmission signal antenna (transport network using microwave technology) for connecting customers with a central area. Therefore, in needed of a decision support system that can provide recommendations planting route of fiber optic cable with the shortest distance in purpose the use of fiber optic cable becoming more efficient. The results of the research were the shortest rule information, showing the distance to be travelled and the map view to enabling users to look at these.
Prescribed and self-reported seasonal training of distance runners.
Hewson, D J; Hopkins, W G
1995-12-01
A survey of 123 distance-running coaches and their best runners was undertaken to describe prescribed seasonal training and its relationship to the performance and self-reported training of the runners. The runners were 43 females and 80 males, aged 24 +/- 8 years (mean +/- S.D.), training for events from 800 m to the marathon, with seasonal best paces of 86 +/- 6% of sex- and age-group world records. The coaches and runners completed a questionnaire on typical weekly volumes of interval and strength training, and typical weekly volumes and paces of moderate and hard continuous running, for build-up, pre-competition, competition and post-competition phases of a season. Prescribed training decreased in volume and increased in intensity from the build-up through to the competition phase, and had similarities with 'long slow distance' training. Coaches of the faster runners prescribed longer build-ups, greater volumes of moderate continuous running and slower relative paces of continuous running (r = 0.19-0.36, P < 0.05), suggesting beneficial effects of not training close to competition pace. The mean training volumes and paces prescribed by the coaches were similar to those reported by the runners, but the correlations between prescribed and reported training were poor (r = 0.2-0.6). Coaches may therefore need to monitor their runners' training more closely.
ERIC Educational Resources Information Center
Moore, Michael G., Ed.; Cozine, Geoffrey T., Ed.
This book brings together a selection of articles published in "The American Journal of Distance Education" that are related to Web-based delivery of distance education. Articles include: "Performance and Perceptions of Distance Learners in Cyberspace" (Peter Navarro and Judy Shoemaker); "Distance Education for Dentists: Improving the Quality of…
Has Distance Learning Become More Flexible? Reflections of a Distance Learning Student
ERIC Educational Resources Information Center
Thomas, Theda
2012-01-01
This paper provides insight into the way in which distance learning had changed over the past 30 years from the perspective of the author as a distance learning student. The question is then asked as to whether current practice is reducing flexibility for distance learning students? The paper starts with a discussion of flexible learning and the…
Chen, Xilin; Gestring, Mark L; Rosengart, Matthew R; Peitzman, Andrew B; Billiar, Timothy R; Sperry, Jason L; Brown, Joshua B
2018-05-04
Trauma is a time sensitive disease. Helicopter emergency medical services (HEMS) have shown benefit over ground EMS (GEMS), which may be related to reduced prehospital time. The distance at which this time benefit emerges depends on many factors that can vary across regions. Our objective was to determine the threshold distance at which HEMS has shorter prehospital time than GEMS under different conditions. Patients in the PA trauma registry 2000-2013 were included. Distance between zip centroid and trauma center was calculated using straight-line distance for HEMS and driving distance from GIS network analysis for GEMS. Contrast margins from linear regression identified the threshold distance at which HEMS had a significantly lower prehospital time than GEMS, indicated by non-overlapping 95% confidence intervals. The effect of peak traffic times and adverse weather on the threshold distance was evaluated. Geographic effects across EMS regions were also evaluated. A total of 144,741 patients were included with 19% transported by HEMS. Overall, HEMS became faster than GEMS at 7.7miles from the trauma center (p=0.043). HEMS became faster at 6.5miles during peak traffic (p=0.025) compared to 7.9miles during off-peak traffic (p=0.048). Adverse weather increased the distance at which HEMS was faster to 17.1miles (p=0.046) from 7.3miles in clear weather (p=0.036). Significant variation occurred across EMS regions, with threshold distances ranging from 5.4miles to 35.3miles. There was an inverse but non-significant relationship between urban population and threshold distance across EMS regions (ρ -0.351, p=0.28). This is the first study to demonstrate that traffic, weather, and geographic region significantly impact the threshold distance at which HEMS is faster than GEMS. HEMS was faster at shorter distances during peak traffic while adverse weather increased this distance. The threshold distance varied widely across geographic region. These factors must be considered
Ensemble Solute Transport in 2-D Operator-Stable Random Fields
NASA Astrophysics Data System (ADS)
Monnig, N. D.; Benson, D. A.
2006-12-01
The heterogeneous velocity field that exists at many scales in an aquifer will typically cause a dissolved solute plume to grow at a rate faster than Fick's Law predicts. Some statistical model must be adopted to account for the aquifer structure that engenders the velocity heterogeneity. A fractional Brownian motion (fBm) model has been shown to create the long-range correlation that can produce continually faster-than-Fickian plume growth. Previous fBm models have assumed isotropic scaling (defined here by a scalar Hurst coefficient). Motivated by field measurements of aquifer hydraulic conductivity, recent techniques were developed to construct random fields with anisotropic scaling with a self-similarity parameter that is defined by a matrix. The growth of ensemble plumes is analyzed for transport through 2-D "operator- stable" fBm hydraulic conductivity (K) fields. Both the longitudinal and transverse Hurst coefficients are important to both plume growth rates and the timing and duration of breakthrough. Smaller Hurst coefficients in the transverse direction lead to more "continuity" or stratification in the direction of transport. The result is continually faster-than-Fickian growth rates, highly non-Gaussian ensemble plumes, and a longer tail early in the breakthrough curve. Contrary to some analytic stochastic theories for monofractal K fields, the plume growth rate never exceeds Mercado's [1967] purely stratified aquifer growth rate of plume apparent dispersivity proportional to mean distance. Apparent super-Mercado growth must be the result of other factors, such as larger plumes corresponding to either a larger initial plume size or greater variance of the ln(K) field.
Preparing public health nurses for pandemic influenza through distance learning.
Macario, Everly; Benton, Lisa D; Yuen, Janet; Torres, Mara; Macias-Reynolds, Violet; Holsclaw, Patricia; Nakahara, Natalie; Jones, Marcy Connell
2007-01-01
As a global influenza pandemic appears imminent with the spread of avian influenza, the California Department of Health Services (CDHS) and the California Distance Learning Health Network (CDLHN) presented a live 90-min satellite broadcast and subsequent 2-hr small group problem-solving tabletop exercise to practice interventions needed to minimize the consequences of a pandemic event. Public health nurses (PHNs), managers, and other staff in laboratories, clinical care, veterinary medicine, environmental health, public information and safety, emergency management, and transportation down linked the program, broadcast by satellite from the CDHS Richmond Laboratory Campus, to view on-site locally. PHNs represented the professional category with the highest number of participants for those conducting the program outside of California. For those in California, PHNs represented the professional category with the second highest number of participants. Participants and distance-learning facilitators completed a training evaluation survey. Continuing education credits were provided by the Centers for Disease Control and Prevention to participants who completed the satellite broadcast evaluation. This distance-learning-by-satellite method of education paired with an activities-based tabletop exercise, and a focus on local rather than State-based responsibility, marks an innovative method of training PHNs and other staff in emergency preparedness response.
The longer term experiences of parent training: a qualitative analysis.
Furlong, M; McGilloway, S
2015-09-01
Child conduct problems are a major public health priority. Group-based parenting programmes are popular in addressing such problems, but evidence for their longer-term effectiveness is limited. Moreover, process evaluations are rare and little is understood about the key facilitative and inhibitive factors associated with maintaining outcomes in the longer term. This study involved the use of qualitative methods as part of a larger process evaluation to explore the longer-term experiences of parents who participated in a randomized controlled trial (RCT) of the Incredible Years Parenting Programme (IYPP) in disadvantaged settings in Ireland. A series of one-to-one in-depth interviews was conducted with parents at 12- (n = 20) and 18-month follow-up (n = 8) and analysed using constructivist grounded theory. Most parents reported positive child behaviour despite several challenges, but a substantial subset reported periods of relapse in positive outcomes. A relapse in child behaviour was linked to relinquishing skills in stressful times, the negative influence of an unsupportive environment, and the perceived ineffectiveness of parenting skills. Resilience in implementing skills despite adversity, and the utilization of available social supports, were associated with the maintenance of positive outcomes. Strengthening resilience and social support capacities may be important factors in maintaining positive longer-term outcomes. Those who design, research and deliver parenting programmes might consider the possibility of including a relapse-prevention module and/or the provision of post-intervention supports for more vulnerable families. © 2014 John Wiley & Sons Ltd.
Pang, Liping; Close, Murray; Goltz, Mark; Noonan, Mike; Sinton, Lester
2005-04-01
Filtration of Bacillus subtilis spores and the F-RNA phage MS2 (MS2) on a field scale in a coarse alluvial gravel aquifer was evaluated from the authors' previously published data. An advection-dispersion model that is coupled with first-order attachment kinetics was used in this study to interpret microbial concentration vs. time breakthrough curves (BTC) at sampling wells. Based on attachment rates (katt) that were determined by applying the model to the breakthrough data, filter factors (f) were calculated and compared with f values estimated from the slopes of log (cmax/co) vs. distance plots. These two independent approaches resulted in nearly identical filter factors, suggesting that both approaches are useful in determining reductions in microbial concentrations over transport distance. Applying the graphic approach to analyse spatial data, we have also estimated the f values for different aquifers using information provided by some other published field studies. The results show that values of f, in units of log (cmax/co) m(-1), are consistently in the order of 10(-2) for clean coarse gravel aquifers, 10(-3) for contaminated coarse gravel aquifers, and generally 10(-1) for sandy fine gravel aquifers and river and coastal sand aquifers. For each aquifer category, the f values for bacteriophages and bacteria are in the same order-of-magnitude. The f values estimated in this study indicate that for every one-log reduction in microbial concentration in groundwater, it requires a few tens of meters of travel in clean coarse gravel aquifers, but a few hundreds of meters in contaminated coarse gravel aquifers. In contrast, a one-log reduction generally only requires a few meters of travel in sandy fine gravel aquifers and sand aquifers. Considering the highest concentration in human effluent is in the order of 10(4) pfu/l for enteroviruses and 10(6) cfu/100 ml for faecal coliform bacteria, a 7-log reduction in microbial concentration would comply with the drinking
NASA Astrophysics Data System (ADS)
Pang, Liping; Close, Murray; Goltz, Mark; Noonan, Mike; Sinton, Lester
2005-04-01
Filtration of Bacillus subtilis spores and the F-RNA phage MS2 (MS2) on a field scale in a coarse alluvial gravel aquifer was evaluated from the authors' previously published data. An advection-dispersion model that is coupled with first-order attachment kinetics was used in this study to interpret microbial concentration vs. time breakthrough curves (BTC) at sampling wells. Based on attachment rates ( katt) that were determined by applying the model to the breakthrough data, filter factors ( f) were calculated and compared with f values estimated from the slopes of log ( cmax/ co) vs. distance plots. These two independent approaches resulted in nearly identical filter factors, suggesting that both approaches are useful in determining reductions in microbial concentrations over transport distance. Applying the graphic approach to analyse spatial data, we have also estimated the f values for different aquifers using information provided by some other published field studies. The results show that values of f, in units of log ( cmax/ co) m -1, are consistently in the order of 10 -2 for clean coarse gravel aquifers, 10 -3 for contaminated coarse gravel aquifers, and generally 10 -1 for sandy fine gravel aquifers and river and coastal sand aquifers. For each aquifer category, the f values for bacteriophages and bacteria are in the same order-of-magnitude. The f values estimated in this study indicate that for every one-log reduction in microbial concentration in groundwater, it requires a few tens of meters of travel in clean coarse gravel aquifers, but a few hundreds of meters in contaminated coarse gravel aquifers. In contrast, a one-log reduction generally only requires a few meters of travel in sandy fine gravel aquifers and sand aquifers. Considering the highest concentration in human effluent is in the order of 10 4 pfu/l for enteroviruses and 10 6 cfu/100 ml for faecal coliform bacteria, a 7-log reduction in microbial concentration would comply with the drinking
Photocarrier drift distance in organic solar cells and photodetectors
Stolterfoht, Martin; Armin, Ardalan; Philippa, Bronson; White, Ronald D.; Burn, Paul L.; Meredith, Paul; Juška, Gytis; Pivrikas, Almantas
2015-01-01
Light harvesting systems based upon disordered materials are not only widespread in nature, but are also increasingly prevalent in solar cells and photodetectors. Examples include organic semiconductors, which typically possess low charge carrier mobilities and Langevin-type recombination dynamics – both of which negatively impact the device performance. It is accepted wisdom that the “drift distance” (i.e., the distance a photocarrier drifts before recombination) is defined by the mobility-lifetime product in solar cells. We demonstrate that this traditional figure of merit is inadequate for describing the charge transport physics of organic light harvesting systems. It is experimentally shown that the onset of the photocarrier recombination is determined by the electrode charge and we propose the mobility-recombination coefficient product as an alternative figure of merit. The implications of these findings are relevant to a wide range of light harvesting systems and will necessitate a rethink of the critical parameters of charge transport. PMID:25919439
Long distance spin communication in chemical vapour deposited graphene
NASA Astrophysics Data System (ADS)
Kamalakar, M. Venkata; Groenveld, Christiaan; Dankert, André; Dash, Saroj P.
2015-04-01
Graphene is an ideal medium for long-distance spin communication in future spintronic technologies. So far, the prospect is limited by the smaller sizes of exfoliated graphene flakes and lower spin transport properties of large-area chemical vapour-deposited (CVD) graphene. Here we demonstrate a high spintronic performance in CVD graphene on SiO2/Si substrate at room temperature. We show pure spin transport and precession over long channel lengths extending up to 16 μm with a spin lifetime of 1.2 ns and a spin diffusion length ~6 μm at room temperature. These spin parameters are up to six times higher than previous reports and highest at room temperature for any form of pristine graphene on industrial standard SiO2/Si substrates. Our detailed investigation reinforces the observed performance in CVD graphene over wafer scale and opens up new prospects for the development of lateral spin-based memory and logic applications.
Effects of burstiness on the air transportation system
NASA Astrophysics Data System (ADS)
Ito, Hidetaka; Nishinari, Katsuhiro
2017-01-01
The effects of burstiness in complex networks have received considerable attention. In particular, the effects on temporal distance and delays in the air transportation system are significant owing to their huge impact on our society. Therefore, in this paper, the temporal distance of empirical U.S. flight schedule data is compared with that of regularized data without burstiness to analyze the effects of burstiness. The temporal distance is calculated by a graph analysis method considering flight delays, missed connections, flight cancellations, and congestion. In addition, we propose two temporal distance indexes based on passengers' behavior to quantify the effects. As a result, we find that burstiness reduces both the scheduled and the actual temporal distances for business travelers, while delays caused by missed connections and congestion are increased. We also find that the decrease of the scheduled temporal distance by burstiness is offset by an increase of the delays for leisure passengers. Moreover, we discover that the positive effect of burstiness is lost when flight schedules are overcrowded.
Effects of burstiness on the air transportation system.
Ito, Hidetaka; Nishinari, Katsuhiro
2017-01-01
The effects of burstiness in complex networks have received considerable attention. In particular, the effects on temporal distance and delays in the air transportation system are significant owing to their huge impact on our society. Therefore, in this paper, the temporal distance of empirical U.S. flight schedule data is compared with that of regularized data without burstiness to analyze the effects of burstiness. The temporal distance is calculated by a graph analysis method considering flight delays, missed connections, flight cancellations, and congestion. In addition, we propose two temporal distance indexes based on passengers' behavior to quantify the effects. As a result, we find that burstiness reduces both the scheduled and the actual temporal distances for business travelers, while delays caused by missed connections and congestion are increased. We also find that the decrease of the scheduled temporal distance by burstiness is offset by an increase of the delays for leisure passengers. Moreover, we discover that the positive effect of burstiness is lost when flight schedules are overcrowded.
Fuel conservation merits of advanced turboprop transport aircraft
NASA Technical Reports Server (NTRS)
Revell, J. D.; Tullis, R. H.
1977-01-01
The advantages of a propfan powered aircraft for the commercial air transportation system were assessed by the comparison with an equivalent turbofan transport. Comparisons were accomplished on the basis of fuel utilization and operating costs, as well as aircraft weight and size. Advantages of the propfan aircraft, concerning fuel utilization and operating costs, were accomplished by considering: (1) incorporation of propfan performance and acoustic data; (2) revised mission profiles (longer design range and reduction in; and cruise speed) (3) utilization of alternate and advanced technology engines.
ERIC Educational Resources Information Center
Leno, Arthur J.
2003-01-01
Describes the development and implementation of the distance education program at Peirce College. This Internet-mediated distance learning program focuses on practical fields of study, drawing on the college's strengths in business administration, information technology, and paralegal studies. (SLD)
Making Distance Education Borderless.
ERIC Educational Resources Information Center
Srisa-An, Wichit
1997-01-01
Begins with a tribute to Professor G. Ram Reddy (founder of Indira Gandhi National Open University), then focuses on enhancing the role of open universities in providing borderless distance education. Highlights include the need for open distance-education; philosophy and vision; the distance teaching system; the role of information technology;…
Sokolowska, K; Turzanska, M; Nilsson, M-C
2017-11-10
The ubiquitous feather mosses Pleurozium schreberi and Hylocomium splendens form a thick, continuous boundary layer between the soil and the atmosphere, and play important roles in hydrology and nutrient cycling in tundra and boreal ecosystems. The water fluxes among these mosses and environmental factors controlling them are poorly understood. The aim of this study was to investigate whether feather mosses are capable of internal transport and to provide a better understanding of species-specific morphological traits underlying this function. The impacts of environmental conditions on their internal transport rates were also investigated. Cells involved in water and food conduction in P. schreberi and H. splendens were identified by transmission electron microscopy. Symplasmic and apoplasmic fluorescent tracers were applied to the moss stems to determine the routes of internal short- and long-distance transport and the impact of air humidity on the transport rates. Symplasmic transport over short distances occurs via food-conducting cells in both mosses. Pleurozium schreberi is also capable of apoplasmic internal long-distance transport via a central strand of hydroids. These are absent in H. splendens. Reduced air humidity significantly increased the internal transport of both species, and the increase was significantly faster for P. schreberi than for H. splendens. Pleurozium schreberi and Hylocomium splendens are capable of internal transport but the pathway and conductivity differ due to differences in stem anatomy. These results help explain their varying desiccation tolerance and possibly their differing physiology and autecology and, ultimately, their impact on ecosystem functioning. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com
Keeping one's distance: the influence of spatial distance cues on affect and evaluation.
Williams, Lawrence E; Bargh, John A
2008-03-01
Current conceptualizations of psychological distance (e.g., construal-level theory) refer to the degree of overlap between the self and some other person, place, or point in time. We propose a complementary view in which perceptual and motor representations of physical distance influence people's thoughts and feelings without reference to the self, extending research and theory on the effects of distance into domains where construal-level theory is silent. Across four experiments, participants were primed with either spatial closeness or spatial distance by plotting an assigned set of points on a Cartesian coordinate plane. Compared with the closeness prime, the distance prime produced greater enjoyment of media depicting embarrassment (Study 1), less emotional distress from violent media (Study 2), lower estimates of the number of calories in unhealthy food (Study 3), and weaker reports of emotional attachments to family members and hometowns (Study 4). These results support a broader conceptualization of distance-mediated effects on judgment and affect.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eslinger, Paul W.; Bowyer, Ted W.; Cameron, Ian M.
2015-10-01
The International Monitoring System contains up to 80 stations around the world that have aerosol and xenon monitoring systems designed to detect releases of radioactive materials to the atmosphere from nuclear tests. A rule of thumb description of plume concentration and duration versus time and distance from the release point is useful when designing and deploying new sample collection systems. This paper uses plume development from atmospheric transport modeling to provide a power-law rule describing atmospheric dilution factors as a function of distance from the release point.
Weschenfelder, A V; Torrey, S; Devillers, N; Crowe, T; Bassols, A; Saco, Y; Piñeiro, M; Saucier, L; Faucitano, L
2012-09-01
loss percentages in the LM and greater (P = 0.002) drip losses and a paler color (greater L* values, P = 0.02) in the SM than 50NN pigs. When used for long distance transportation under controlled conditions, the PB trailer produced no detrimental effects on animal welfare or pork quality. Pigs with 50% Pietrain crossbreeding appear to be more responsive to transport stress, having the potential to produce acceptable carcass and pork quality, provided pigs are free of the HAL gene.
NASA Technical Reports Server (NTRS)
Shaw, Robert J.; Koops, Leigh; Hines, Richard
1997-01-01
Ongoing NASA-funded and privately funded studies continue to indicate that an opportunity exists for a second generation supersonic commercial airliner, or High-Speed Civil Transport (HSCT), to become a key part of the 21st century international air transportation system. Long distance air travel is projected to increase at about 5 percent per annum over the next two decades. This projection suggests that by the year 2015, more than 600,000 passengers per day will be traveling long distances, predominantly over water. These routes would be among the most desirable for an HSCT as part of the international air transportation system. Beyond the year 2000, this portion of the air transportation market is projected to be the fastest growing segment.
NASA Astrophysics Data System (ADS)
Chen, Xiaodian; Deng, Licai; de Grijs, Richard; Wang, Shu; Feng, Yuting
2018-06-01
W Ursa Majoris (W UMa)-type contact binary systems (CBs) are useful statistical distance indicators because of their large numbers. Here, we establish (orbital) period–luminosity relations (PLRs) in 12 optical to mid-infrared bands (GBVRIJHK s W1W2W3W4) based on 183 nearby W UMa-type CBs with accurate Tycho–Gaia parallaxes. The 1σ dispersion of the PLRs decreases from optical to near- and mid-infrared wavelengths. The minimum scatter, 0.16 mag, implies that W UMa-type CBs can be used to recover distances to 7% precision. Applying our newly determined PLRs to 19 open clusters containing W UMa-type CBs demonstrates that the PLR and open cluster CB distance scales are mutually consistent to within 1%. Adopting our PLRs as secondary distance indicators, we compiled a catalog of 55,603 CB candidates, of which 80% have distance estimates based on a combination of optical, near-infrared, and mid-infrared photometry. Using Fourier decomposition, 27,318 high-probability W UMa-type CBs were selected. The resulting 8% distance accuracy implies that our sample encompasses the largest number of objects with accurate distances within a local volume with a radius of 3 kpc available to date. The distribution of W UMa-type CBs in the Galaxy suggests that in different environments, the CB luminosity function may be different: larger numbers of brighter (longer-period) W UMa-type CBs are found in younger environments.
Kinematic Distances: A Monte Carlo Method
NASA Astrophysics Data System (ADS)
Wenger, Trey V.; Balser, Dana S.; Anderson, L. D.; Bania, T. M.
2018-03-01
Distances to high-mass star-forming regions (HMSFRs) in the Milky Way are a crucial constraint on the structure of the Galaxy. Only kinematic distances are available for a majority of the HMSFRs in the Milky Way. Here, we compare the kinematic and parallax distances of 75 Galactic HMSFRs to assess the accuracy of kinematic distances. We derive the kinematic distances using three different methods: the traditional method using the Brand & Blitz rotation curve (Method A), the traditional method using the Reid et al. rotation curve and updated solar motion parameters (Method B), and a Monte Carlo technique (Method C). Methods B and C produce kinematic distances closest to the parallax distances, with median differences of 13% (0.43 {kpc}) and 17% (0.42 {kpc}), respectively. Except in the vicinity of the tangent point, the kinematic distance uncertainties derived by Method C are smaller than those of Methods A and B. In a large region of the Galaxy, the Method C kinematic distances constrain both the distances and the Galactocentric positions of HMSFRs more accurately than parallax distances. Beyond the tangent point along ℓ = 30°, for example, the Method C kinematic distance uncertainties reach a minimum of 10% of the parallax distance uncertainty at a distance of 14 {kpc}. We develop a prescription for deriving and applying the Method C kinematic distances and distance uncertainties. The code to generate the Method C kinematic distances is publicly available and may be utilized through an online tool.
Enhanced energy transport in genetically engineered excitonic networks.
Park, Heechul; Heldman, Nimrod; Rebentrost, Patrick; Abbondanza, Luigi; Iagatti, Alessandro; Alessi, Andrea; Patrizi, Barbara; Salvalaggio, Mario; Bussotti, Laura; Mohseni, Masoud; Caruso, Filippo; Johnsen, Hannah C; Fusco, Roberto; Foggi, Paolo; Scudo, Petra F; Lloyd, Seth; Belcher, Angela M
2016-02-01
One of the challenges for achieving efficient exciton transport in solar energy conversion systems is precise structural control of the light-harvesting building blocks. Here, we create a tunable material consisting of a connected chromophore network on an ordered biological virus template. Using genetic engineering, we establish a link between the inter-chromophoric distances and emerging transport properties. The combination of spectroscopy measurements and dynamic modelling enables us to elucidate quantum coherent and classical incoherent energy transport at room temperature. Through genetic modifications, we obtain a significant enhancement of exciton diffusion length of about 68% in an intermediate quantum-classical regime.
Factors influencing mode of transport in older adolescents: a qualitative study
2013-01-01
Background Since a decline in activity levels occurs in adolescence, active transport could be important to increase daily physical activity in older adolescents (17–18 years). To promote active transport, it is necessary to be aware of the barriers and facilitators of this type of transport, but also of other transport modes. This study sought to uncover the factors influencing the choice of transport mode for short distance travel to various destinations in older adolescents using focus groups. Methods Thirty-two focus group volunteers (mean age of 17 ± 1.2 years) were recruited from the two final years of the secondary school in Antwerp (Belgium). Five focus groups were conducted (five to eight participants/group). Content analysis was performed using NVivo 9 software (QSR International). Grounded theory was used to derive categories and subcategories. Results Data were categorized in three main themes with several subcategories: personal factors (high autonomy, low costs and health), social factors (good social support) and physical environmental factors (short travel time, good access to transport modes and to facilities, good weather, an adapted built environment, perceived safety and ecology). Conclusions For older adolescents, the interplay between short travel time, high autonomy, good social support, low costs, good access to transport modes and facilities, and good weather was important for choosing active transport over other transport forms for travelling short distances to various destinations. Other well-known factors such as safety, ecology and health seemed not to have a big influence on their transport mode choice. PMID:23574974
20 CFR 220.20 - Notice that an annuitant is no longer disabled.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Notice that an annuitant is no longer disabled. 220.20 Section 220.20 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE... Employee's Regular Railroad Occupation § 220.20 Notice that an annuitant is no longer disabled. The...
20 CFR 220.20 - Notice that an annuitant is no longer disabled.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Notice that an annuitant is no longer disabled. 220.20 Section 220.20 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE... Employee's Regular Railroad Occupation § 220.20 Notice that an annuitant is no longer disabled. The...
20 CFR 220.20 - Notice that an annuitant is no longer disabled.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Notice that an annuitant is no longer disabled. 220.20 Section 220.20 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE... Employee's Regular Railroad Occupation § 220.20 Notice that an annuitant is no longer disabled. The...
20 CFR 220.20 - Notice that an annuitant is no longer disabled.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Notice that an annuitant is no longer disabled. 220.20 Section 220.20 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD... Regular Railroad Occupation § 220.20 Notice that an annuitant is no longer disabled. The regulation...
20 CFR 220.20 - Notice that an annuitant is no longer disabled.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Notice that an annuitant is no longer disabled. 220.20 Section 220.20 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD... Regular Railroad Occupation § 220.20 Notice that an annuitant is no longer disabled. The regulation...
Reavey, Caitlin T; Hickman, Mark J; Dobi, Krista C; Botstein, David; Winston, Fred
2015-10-01
Studies of natural populations of many organisms have shown that traits are often complex, caused by contributions of mutations in multiple genes. In contrast, genetic studies in the laboratory primarily focus on studying the phenotypes caused by mutations in a single gene. However, the single mutation approach may be limited with respect to the breadth and degree of new phenotypes that can be found. We have taken the approach of isolating complex, or polygenic mutants in the lab to study the regulation of transcriptional activation distance in yeast. While most aspects of eukaryotic transcription are conserved from yeast to human, transcriptional activation distance is not. In Saccharomyces cerevisiae, the upstream activating sequence (UAS) is generally found within 450 base pairs of the transcription start site (TSS) and when the UAS is moved too far away, activation no longer occurs. In contrast, metazoan enhancers can activate from as far as several hundred kilobases from the TSS. Previously, we identified single mutations that allow transcription activation to occur at a greater-than-normal distance from the GAL1 UAS. As the single mutant phenotypes were weak, we have now isolated polygenic mutants that possess strong long-distance phenotypes. By identification of the causative mutations we have accounted for most of the heritability of the phenotype in each strain and have provided evidence that the Mediator coactivator complex plays both positive and negative roles in the regulation of transcription activation distance. Copyright © 2015 by the Genetics Society of America.
The axonal transport of mitochondria
Saxton, William M.; Hollenbeck, Peter J.
2012-01-01
Vigorous transport of cytoplasmic components along axons over substantial distances is crucial for the maintenance of neuron structure and function. The transport of mitochondria, which serves to distribute mitochondrial functions in a dynamic and non-uniform fashion, has attracted special interest in recent years following the discovery of functional connections among microtubules, motor proteins and mitochondria, and their influences on neurodegenerative diseases. Although the motor proteins that drive mitochondrial movement are now well characterized, the mechanisms by which anterograde and retrograde movement are coordinated with one another and with stationary axonal mitochondria are not yet understood. In this Commentary, we review why mitochondria move and how they move, focusing particularly on recent studies of transport regulation, which implicate control of motor activity by specific cell-signaling pathways, regulation of motor access to transport tracks and static microtubule–mitochondrion linkers. A detailed mechanism for modulating anterograde mitochondrial transport has been identified that involves Miro, a mitochondrial Ca2+-binding GTPase, which with associated proteins, can bind and control kinesin-1. Elements of the Miro complex also have important roles in mitochondrial fission–fusion dynamics, highlighting questions about the interdependence of biogenesis, transport, dynamics, maintenance and degradation. PMID:22619228
Distance to testing sites and its association with timing of HIV diagnosis.
Cope, Anna B; Powers, Kimberly A; Serre, Marc L; Escamilla, Veronica; Emch, Michael E; Leone, Peter A; Mobley, Victoria L; Miller, William C
2016-11-01
Early HIV diagnosis enables prompt treatment initiation, thereby contributing to decreased morbidity, mortality, and transmission. We aimed to describe the association between distance from residence to testing sites and HIV disease stage at diagnosis. Using HIV surveillance data, we identified all new HIV diagnoses made at publicly funded testing sites in central North Carolina during 2005-2013. Early-stage HIV was defined as acute HIV (antibody-negative test with a positive HIV RNA) or recent HIV (normalized optical density <0.8 on the BED assay for non-AIDS cases); remaining diagnoses were considered post-early-stage HIV. Street distance between residence at diagnosis and (1) the closest testing site and (2) the diagnosis site was dichotomized at 5 miles. We fit log-binomial models using generalized estimating equations to estimate prevalence ratios (PR) and robust 95% confidence intervals (CI) for post-early-stage diagnoses by distance. Models were adjusted for race/ethnicity and testing period. Most of the 3028 new diagnoses were black (N = 2144; 70.8%), men who have sex with men (N = 1685; 55.7%), and post-early-stage HIV diagnoses (N = 2010; 66.4%). Overall, 1145 (37.8%) cases traveled <5 miles for a diagnosis. Among cases traveling ≥5 miles for a diagnosis, 1273 (67.6%) lived <5 miles from a different site. Residing ≥5 miles from a testing site was not associated with post-early-stage HIV (adjusted PR, 95% CI: 0.98, 0.92-1.04), but traveling ≥5 miles for a diagnosis was associated with higher post-early HIV prevalence (1.07, 1.02-1.13). Most of the elevated prevalence observed in cases traveling ≥5 miles for a diagnosis occurred among those living <5 miles from a different site (1.09, 1.03-1.16). Modest increases in post-early-stage HIV diagnosis were apparent among persons living near a site, but choosing to travel longer distances to test. Understanding reasons for increased travel distances could improve accessibility and
MPATHav: A software prototype for multiobjective routing in transportation risk assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ganter, J.H.; Smith, J.D.
Most routing problems depend on several important variables: transport distance, population exposure, accident rate, mandated roads (e.g., HM-164 regulations), and proximity to emergency response resources are typical. These variables may need to be minimized or maximized, and often are weighted. `Objectives` to be satisfied by the analysis are thus created. The resulting problems can be approached by combining spatial analysis techniques from geographic information systems (GIS) with multiobjective analysis techniques from the field of operations research (OR); we call this hybrid multiobjective spatial analysis` (MOSA). MOSA can be used to discover, display, and compare a range of solutions that satisfymore » a set of objectives to varying degrees. For instance, a suite of solutions may include: one solution that provides short transport distances, but at a cost of high exposure; another solution that provides low exposure, but long distances; and a range of solutions between these two extremes.« less
Conceptual design study of improved 1985 remote lift-fan V/STOL commercial transports
NASA Technical Reports Server (NTRS)
Cavage, R. L.
1975-01-01
A design study was conducted for a remote lift-fan commercial V/STOL transport for the 1985 time period. The investigation centered on the commercial short haul transportation application to carry 100 passengers over trip distances of 400 nautical miles from a vertical takeoff and landing, and 800 nautical miles after a 1600 foot STOL takeoff. The study included investigation of alternate numbers and arrangements of lift fans and gas generators, fan control margins, and structural concepts. The sensitivity of direct operating costs to major airframe parameters, airframe costs, propulsion costs, yearly aircraft utilization rate, and trip distances are evaluated.
Suppression of Systematic Errors of Electronic Distance Meters for Measurement of Short Distances
Braun, Jaroslav; Štroner, Martin; Urban, Rudolf; Dvořáček, Filip
2015-01-01
In modern industrial geodesy, high demands are placed on the final accuracy, with expectations currently falling below 1 mm. The measurement methodology and surveying instruments used have to be adjusted to meet these stringent requirements, especially the total stations as the most often used instruments. A standard deviation of the measured distance is the accuracy parameter, commonly between 1 and 2 mm. This parameter is often discussed in conjunction with the determination of the real accuracy of measurements at very short distances (5–50 m) because it is generally known that this accuracy cannot be increased by simply repeating the measurement because a considerable part of the error is systematic. This article describes the detailed testing of electronic distance meters to determine the absolute size of their systematic errors, their stability over time, their repeatability and the real accuracy of their distance measurement. Twenty instruments (total stations) have been tested, and more than 60,000 distances in total were measured to determine the accuracy and precision parameters of the distance meters. Based on the experiments’ results, calibration procedures were designed, including a special correction function for each instrument, whose usage reduces the standard deviation of the measurement of distance by at least 50%. PMID:26258777
Suppression of Systematic Errors of Electronic Distance Meters for Measurement of Short Distances.
Braun, Jaroslav; Štroner, Martin; Urban, Rudolf; Dvoček, Filip
2015-08-06
In modern industrial geodesy, high demands are placed on the final accuracy, with expectations currently falling below 1 mm. The measurement methodology and surveying instruments used have to be adjusted to meet these stringent requirements, especially the total stations as the most often used instruments. A standard deviation of the measured distance is the accuracy parameter, commonly between 1 and 2 mm. This parameter is often discussed in conjunction with the determination of the real accuracy of measurements at very short distances (5-50 m) because it is generally known that this accuracy cannot be increased by simply repeating the measurement because a considerable part of the error is systematic. This article describes the detailed testing of electronic distance meters to determine the absolute size of their systematic errors, their stability over time, their repeatability and the real accuracy of their distance measurement. Twenty instruments (total stations) have been tested, and more than 60,000 distances in total were measured to determine the accuracy and precision parameters of the distance meters. Based on the experiments' results, calibration procedures were designed, including a special correction function for each instrument, whose usage reduces the standard deviation of the measurement of distance by at least 50%.
ERIC Educational Resources Information Center
Adey, David, Comp.; And Others
Eighteen papers from the University of South Africa's Conference on Distance Education are presented on issues in education and distance education. They include: "Distance Education in Africa's Educational Development: The Case of Ghana" (Joe K. Ansere); "Distance Education: A Solution to the Economic Problems of Education in…
Emission projections of the transport Sector in China: 2015-2040
NASA Astrophysics Data System (ADS)
Yan, L.
2016-12-01
Driven by the significant growth freight and passenger transport demand, transport sector has become a sector that is largely responsible for increases in emissions of atmospheric pollutants (NOx, CO, HC, PM2.5) in China. Figuring out the emission trend in China's transport sector has great influence on formulating emission reduction measures in the future. In this work, both on-road and off-road transport emissions in China were estimated from 2015 to 2040 for CO, NOx, HC and PM2.5. The projection was conducted based on on the energy consumption structure forecast from IEA (International Energy Agency), the future national average annual distance traveled per vehicle and fuel consumption per distance derived from simulation results of the Fuel Economy and Environmental Impact (FEEI) model. The results show that the ownership of on-road vehicles in China increases rapidly during 2015 to 2030 and then the growth slows down. Finally, the total amount reaches up to 522 million in 2040 in which 84.5% turns out to be light-duty vehicles. Because current control legislations for the transport sector in China will continue to be strengthened in the future, the total emissions of China's transport sector were projected to peak around 2030, due to the improvement of vehicle emission standard and the retirement of old vehicles are the most effective measures. The off-road transport will become the main contributor to emissions from transport sector in China since 2030. This work provides a new perspective to understand emissions from both on-road and off-road transport in China, which can support the achievement of improving air quality promised by the Chinese government. This work provides a new perspective to understand the emission trends of on-road and off-road transport sector in China from 2015 to 2040, which can support the achievement of the air quality goal promised by the Chinese government. Driven by the significant growth freight and passenger transport demand
Immediate and Longer-Term Stressors and the Mental Health of Hurricane Ike Survivors
Lowe, Sarah R.; Tracy, Melissa; Cerdá, Magdalena; Norris, Fran H.; Galea, Sandro
2014-01-01
Previous research has documented that individuals exposed to more stressors during disasters and their immediate aftermath (immediate stressors) are at risk of experiencing longer-term postdisaster stressors. Longer-term stressors, in turn, have been found to play a key role in shaping postdisaster psychological functioning. Few studies have simultaneously explored the links from immediate to longer-term stressors, and from longer-term stressors to psychological functioning, however. Additionally, studies have inadequately explored whether postdisaster psychological symptoms influence longer-term stressors. In the current study, we aimed to fill these gaps. Participants (N = 448) were from population-based study of Hurricane Ike survivors and completed assessments 2–5 months (Wave 1), 5–9 months (Wave 2) and 14–18 months (Wave 3) postdisaster. Through path analysis, we found that immediate stressors, assessed at Wave 1, were positively associated with Wave 2 and Wave 3 stressors, which in turn were positively associated with Wave 2 and Wave 3 posttraumatic stress and depressive symptoms. Wave 2 posttraumatic stress symptoms were positively associated with Wave 3 stressors, and Wave 1 depressive symptoms were positively associated with Wave 2 stressors. The findings suggest that policies and interventions can reduce the impact of disasters on mental health by preventing and alleviating both immediate and longer-term postdisaster stressors. PMID:24343752
Insight to the express transport network
NASA Astrophysics Data System (ADS)
Yang, Hua; Nie, Yuchao; Zhang, Hongbin; Di, Zengru; Fan, Ying
2009-09-01
The express delivery industry is developing rapidly in recent years and has attracted attention in many fields. Express shipment service requires that parcels be delivered in a limited time with a low operation cost, which requests a high level and efficient express transport network (ETN). The ETN is constructed based on the public transport networks, especially the airline network. It is similar to the airline network in some aspects, while it has its own feature. With the complex network theory, the topological properties of the ETN are analyzed deeply. We find that the ETN has the small-world property, with disassortative mixing behavior and rich club phenomenon. It also shows difference from the airline network in some features, such as edge density and average shortest path. Analysis on the corresponding distance-weighted network shows that the distance distribution displays a truncated power-law behavior. At last, an evolving model, which takes both geographical constraint and preference attachment into account, is proposed. The model shows similar properties with the empirical results.
Perchoux, Camille; Nazare, Julie-Anne; Benmarhnia, Tarik; Salze, Paul; Feuillet, Thierry; Hercberg, Serge; Hess, Franck; Menai, Mehdi; Weber, Christiane; Charreire, Hélène; Enaux, Christophe; Oppert, Jean-Michel; Simon, Chantal
2017-06-12
Active transportation has been associated with favorable health outcomes. Previous research highlighted the influence of neighborhood educational level on active transportation. However, little is known regarding the effect of commuting distance on social disparities in active commuting. In this regard, women have been poorly studied. The objective of this paper was to evaluate the relationship between neighborhood educational level and active commuting, and to assess whether the commuting distance modifies this relationship in adult women. This cross-sectional study is based on a subsample of women from the Nutrinet-Santé web-cohort (N = 1169). Binomial, log-binomial and negative binomial regressions were used to assess the associations between neighborhood education level and (i) the likelihood of reporting any active commuting time, and (ii) the share of commuting time made by active transportation modes. Potential effect measure modification of distance to work on the previous associations was assessed both on the additive and the multiplicative scales. Neighborhood education level was positively associated with the probability of reporting any active commuting time (relative risk = 1.774; p < 0.05) and the share of commuting time spent active (relative risk = 1.423; p < 0.05). The impact of neighborhood education was greater at long distances to work for both outcomes. Our results suggest that neighborhood educational disparities in active commuting tend to increase with commuting distance among women. Further research is needed to provide geographically driven guidance for health promotion intervention aiming at reducing disparities in active transportation among socioeconomic groups.
The semantic distance task: Quantifying semantic distance with semantic network path length.
Kenett, Yoed N; Levi, Effi; Anaki, David; Faust, Miriam
2017-09-01
Semantic distance is a determining factor in cognitive processes, such as semantic priming, operating upon semantic memory. The main computational approach to compute semantic distance is through latent semantic analysis (LSA). However, objections have been raised against this approach, mainly in its failure at predicting semantic priming. We propose a novel approach to computing semantic distance, based on network science methodology. Path length in a semantic network represents the amount of steps needed to traverse from 1 word in the network to the other. We examine whether path length can be used as a measure of semantic distance, by investigating how path length affect performance in a semantic relatedness judgment task and recall from memory. Our results show a differential effect on performance: Up to 4 steps separating between word-pairs, participants exhibit an increase in reaction time (RT) and decrease in the percentage of word-pairs judged as related. From 4 steps onward, participants exhibit a significant decrease in RT and the word-pairs are dominantly judged as unrelated. Furthermore, we show that as path length between word-pairs increases, success in free- and cued-recall decreases. Finally, we demonstrate how our measure outperforms computational methods measuring semantic distance (LSA and positive pointwise mutual information) in predicting participants RT and subjective judgments of semantic strength. Thus, we provide a computational alternative to computing semantic distance. Furthermore, this approach addresses key issues in cognitive theory, namely the breadth of the spreading activation process and the effect of semantic distance on memory retrieval. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Reducing the distance: equity issues in distance learning in public education
NASA Astrophysics Data System (ADS)
Campbell, Patricia B.; Storo, Jennifer
1996-12-01
Distance learning and educational equity both began with an emphasis on access, on providing underserved students with an increased access to education. Today definitions of equity have gone beyond simple access to include equal or equivalent treatment and outcomes while definitions of underserved students have expanded to include girls, children of color, children with limited English proficiency and children with disabilities. At the same time the definition of distance learning has expanded to include new technologies, new audiences and new roles. Based on these new definitions and roles, the article raises a number of equity challenges for distance learning educators centering around who is taught, what is taught and how the teaching is done. To answer these challenges, a series of recommendations are suggested that educators can implement to make distance learning a leader in increasing educational equity for all students. The time to act is now.
Garrard, Georgia E; McCarthy, Michael A; Vesk, Peter A; Radford, James Q; Bennett, Andrew F
2012-01-01
1. Informative Bayesian priors can improve the precision of estimates in ecological studies or estimate parameters for which little or no information is available. While Bayesian analyses are becoming more popular in ecology, the use of strongly informative priors remains rare, perhaps because examples of informative priors are not readily available in the published literature. 2. Dispersal distance is an important ecological parameter, but is difficult to measure and estimates are scarce. General models that provide informative prior estimates of dispersal distances will therefore be valuable. 3. Using a world-wide data set on birds, we develop a predictive model of median natal dispersal distance that includes body mass, wingspan, sex and feeding guild. This model predicts median dispersal distance well when using the fitted data and an independent test data set, explaining up to 53% of the variation. 4. Using this model, we predict a priori estimates of median dispersal distance for 57 woodland-dependent bird species in northern Victoria, Australia. These estimates are then used to investigate the relationship between dispersal ability and vulnerability to landscape-scale changes in habitat cover and fragmentation. 5. We find evidence that woodland bird species with poor predicted dispersal ability are more vulnerable to habitat fragmentation than those species with longer predicted dispersal distances, thus improving the understanding of this important phenomenon. 6. The value of constructing informative priors from existing information is also demonstrated. When used as informative priors for four example species, predicted dispersal distances reduced the 95% credible intervals of posterior estimates of dispersal distance by 8-19%. Further, should we have wished to collect information on avian dispersal distances and relate it to species' responses to habitat loss and fragmentation, data from 221 individuals across 57 species would have been required to obtain
Majumdar, Ayan; Huang, Haiying
2008-05-20
The fabrication, implementation, and evaluation of an in-fiber white-light interferometric distance sensor that is capable of measuring the absolute value of an arbitrary small distance are presented. Taking advantage of the mode-coupling effect of a long-period fiber grating, an additional cavity distance is added to the optical path difference of the distance sensor; therefore, it can generate a sufficient number of fringes for distance demodulation even if the free-space cavity distance is very small. It is experimentally verified that the distance sensor is capable of measuring small distances that are beyond the capability of a Fabry-Perot interferometric distance sensor.
Long Distance Dispersal Potential of Two Seagrasses Thalassia hemprichii and Halophila ovalis
Wu, Kuoyan; Chen, Ching-Nen Nathan; Soong, Keryea
2016-01-01
The wide distribution of many seagrasses may be attributable to exploitation of currents. However, many species have seeds heavier than seawater, limiting surface floating, and thus, deep water becomes a potential barrier between suitable habitats. In this investigation, we studied the dispersal potential of various life history stages of two species of seagrasses, Thalassia hemprichii and Halophila ovalis, at Dongsha Atoll and Penghu Islands in Taiwan Strait, west Pacific. The adult plants of both species, often dislodged naturally from substrate by waves, could float, but only that of T. hemprichii could float for months and still remain alive and potentially able to colonize new territories. The seedlings of T. hemprichii could also float for about a month once failing to anchor to substrate of coral sand, but that of H. ovalis could not. The fruits and seeds of T. hemprichii could both float, but for too short a duration to enable long distance travel; those seeds released from long floating fruits had low germination rates in our tests. Obviously, their seeds are not adaptive for long distance dispersal. Fruits and seeds of H. ovalis do not float. The potential of animals as vectors was tested by feeding fruits and seeds of both species to a goose, a duck, and two fish in the laboratory. The fruits and seeds of T. hemprichii were digested and could no longer germinate; those of H. ovalis could pass through the digestive tracts and have a much higher germination rates than uningested controls. Therefore, birds could be important vectors for long distance dispersal of H. ovalis. The two seagrasses adopted very different dispersal mechanisms for long distance travel, and both exploited traits originally adaptive for other purposes. PMID:27248695
Long Distance Dispersal Potential of Two Seagrasses Thalassia hemprichii and Halophila ovalis.
Wu, Kuoyan; Chen, Ching-Nen Nathan; Soong, Keryea
2016-01-01
The wide distribution of many seagrasses may be attributable to exploitation of currents. However, many species have seeds heavier than seawater, limiting surface floating, and thus, deep water becomes a potential barrier between suitable habitats. In this investigation, we studied the dispersal potential of various life history stages of two species of seagrasses, Thalassia hemprichii and Halophila ovalis, at Dongsha Atoll and Penghu Islands in Taiwan Strait, west Pacific. The adult plants of both species, often dislodged naturally from substrate by waves, could float, but only that of T. hemprichii could float for months and still remain alive and potentially able to colonize new territories. The seedlings of T. hemprichii could also float for about a month once failing to anchor to substrate of coral sand, but that of H. ovalis could not. The fruits and seeds of T. hemprichii could both float, but for too short a duration to enable long distance travel; those seeds released from long floating fruits had low germination rates in our tests. Obviously, their seeds are not adaptive for long distance dispersal. Fruits and seeds of H. ovalis do not float. The potential of animals as vectors was tested by feeding fruits and seeds of both species to a goose, a duck, and two fish in the laboratory. The fruits and seeds of T. hemprichii were digested and could no longer germinate; those of H. ovalis could pass through the digestive tracts and have a much higher germination rates than uningested controls. Therefore, birds could be important vectors for long distance dispersal of H. ovalis. The two seagrasses adopted very different dispersal mechanisms for long distance travel, and both exploited traits originally adaptive for other purposes.
Distance Magic-Type and Distance Antimagic-Type Labelings of Graphs
NASA Astrophysics Data System (ADS)
Freyberg, Bryan J.
Generally speaking, a distance magic-type labeling of a graph G of order n is a bijection l from the vertex set of the graph to the first n natural numbers or to the elements of a group of order n, with the property that the weight of each vertex is the same. The weight of a vertex x is defined as the sum (or appropriate group operation) of all the labels of vertices adjacent to x. If instead we require that all weights differ, then we refer to the labeling as a distance antimagic-type labeling. This idea can be generalized for directed graphs; the weight will take into consideration the direction of the arcs. In this manuscript, we provide new results for d-handicap labeling, a distance antimagic-type labeling, and introduce a new distance magic-type labeling called orientable Gamma-distance magic labeling. A d-handicap distance antimagic labeling (or just d-handicap labeling for short) of a graph G = ( V,E) of order n is a bijection l from V to the set {1,2,...,n} with induced weight function [special characters omitted]. such that l(xi) = i and the sequence of weights w(x 1),w(x2),...,w (xn) forms an arithmetic sequence with constant difference d at least 1. If a graph G admits a d-handicap labeling, we say G is a d-handicap graph. A d-handicap incomplete tournament, H(n,k,d ) is an incomplete tournament of n teams ranked with the first n natural numbers such that each team plays exactly k games and the strength of schedule of the ith ranked team is d more than the i + 1st ranked team. That is, strength of schedule increases arithmetically with strength of team. Constructing an H(n,k,d) is equivalent to finding a d-handicap labeling of a k-regular graph of order n.. In Chapter 2 we provide general constructions for every d for large classes of both n and k, providing breadfth and depth to the catalog of known H(n,k,d)'s. In Chapters 3 - 6, we introduce a new type of labeling called orientable Gamma-distance magic labeling. Let Gamma be an abelian group of order
NASA Astrophysics Data System (ADS)
Pede, Timothy J.
There is much potential to decrease energy consumption in the U.S. by encouraging compact, centralized development. Although many studies have examined the extent to which built environment and demographic factors are related to household energy use, few have considered both building and transportation energy together. We hypothesized that residents living further from city centers, or urban cores, consume more energy for both purposes than their inner city counterparts, resulting in a direct relationship between building and transportation energy usage. This hypothesis was tested with two case studies. The first focused on New York City. Annual building energy per unit of parcels, or tax lots, containing large multi-family structures was compared to the daily transportation energy use per household of traffic analysis zones (TAZs) (estimated with a regional travel demand model). Transportation energy showed a strong spatial pattern, with distance to urban core explaining 63% of variation in consumption. Building energy use was randomly distributed, resulting in a weak negative correlation with transportation energy. However, both correlation with distance to urban core and transportation energy became significant and positive when portion of detached single-family units for TAZs was used as a proxy for building energy. Structural equation models (SEMs) revealed a direct relationship between log lot depth and both uses of energy, and inverse relationship between portion of attached housing units and transportation energy. This supports the notion that sprawling development increases both the building and transportation energy consumption of households. For the second analysis, annual building and automobile energy use per household were estimated for block groups across the 50 most populous U.S. metropolitan regions with Esri Consumer Expenditure Data. Both forms of energy consumption per household were lowest in inner cities and increased at greater distances from
27 CFR 11.34 - Products which may no longer be lawfully sold.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Products which may no longer be lawfully sold. 11.34 Section 11.34 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO... affiliate of the trade buyer has no control, a particular size or brand is no longer permitted to be sold...
The effect of distance traveled on disease outcomes in gestational trophoblastic neoplasia.
Clark, Leslie H; Staley, S Allison; Barber, Emma L; Wysham, Weiya Z; Kim, Kenneth H; Soper, John T
2016-08-01
trophoblastic neoplasia lived 63 miles farther (92 vs 28 miles, P < .001) than patients with low-risk gestational trophoblastic neoplasia. Long-distance travelers had a longer period between antecedent pregnancy and gestational trophoblastic neoplasia diagnosis (10 weeks vs 4.5 weeks, P = .009) and were more likely to receive multiagent chemotherapy (86% vs 61%, P = .03). In this cohort, long distance traveled to obtain care for gestational trophoblastic neoplasia was associated with an increased risk of presenting with high-risk disease and requiring multiagent chemotherapy for treatment. Patients with high-risk gestational trophoblastic neoplasia traveled nearly 100 miles to obtain care. There may be a delay in diagnosis in women traveling more than 50 miles to obtain care; however, we found no difference in recurrence risk for long-distance travelers. Copyright © 2016 Elsevier Inc. All rights reserved.
Humans as long-distance dispersers of rural plant communities.
Auffret, Alistair G; Cousins, Sara A O
2013-01-01
Humans are known for their capacity to disperse organisms long distances. Long-distance dispersal can be important for species threatened by habitat destruction, but research into human-mediated dispersal is often focused upon few and/or invasive species. Here we use citizen science to identify the capacity for humans to disperse seeds on their clothes and footwear from a known species pool in a valuable habitat, allowing for an assessment of the fraction and types of species dispersed by humans in an alternative context. We collected material from volunteers cutting 48 species-rich meadows throughout Sweden. We counted 24,354 seeds of 197 species, representing 34% of the available species pool, including several rare and protected species. However, 71 species (36%) are considered invasive elsewhere in the world. Trait analysis showed that seeds with hooks or other appendages were more likely to be dispersed by humans, as well as those with a persistent seed bank. More activity in a meadow resulted in more dispersal, both in terms of species and representation of the source communities. Average potential dispersal distances were measured at 13 km. We consider humans capable seed dispersers, transporting a significant proportion of the plant communities in which they are active, just like more traditional vectors such as livestock. When rural populations were larger, people might have been regular and effective seed dispersers, and the net rural-urban migration resulting in a reduction in humans in the landscape may have exacerbated the dispersal failure evident in declining plant populations today. With the fragmentation of habitat and changes in land use resulting from agricultural change, and the increased mobility of humans worldwide, the dispersal role of humans may have shifted from providers of regular local and landscape dispersal to providers of much rarer long-distance and regional dispersal, and international invasion.
Cosmic Ray Transport in the Distant Heliosheath
NASA Technical Reports Server (NTRS)
Florinski, V.; Adams, James H.; Washimi, H.
2011-01-01
The character of energetic particle transport in the distant heliosheath and especially in the vicinity of the heliopause could be quite distinct from the other regions of the heliosphere. The magnetic field structure is dominated by a tightly wrapped oscillating heliospheric current sheet which is transported to higher latitudes by the nonradial heliosheath flows. Both Voyagers have, or are expected to enter a region dominated by the sectored field formed during the preceding solar maximum. As the plasma flow slows down on approach to the heliopause, the distance between the folds of the current sheet decreases to the point where it becomes comparable to the cyclotron radius of an energetic ion, such as a galactic cosmic ray. Then, a charged particle can effectively drift across a stack of magnetic sectors with a speed comparable with the particle s velocity. Cosmic rays should also be able to efficiently diffuse across the mean magnetic field if the distance between sector boundaries varies. The region of the heliopause could thus be much more permeable to cosmic rays than was previously thought. This new transport proposed mechanism could explain the very high intensities (approaching the model interstellar values) of galactic cosmic rays measured by Voyager 1 during 2010-2011.
Massarweh, Nader N.; Chiang, Yi-Ju; Xing, Yan; Chang, George J.; Haynes, Alex B.; You, Y. Nancy; Feig, Barry W.; Cormier, Janice N.
2014-01-01
Purpose Health care access and advanced cancer stage are associated with oncologic outcomes for numerous common cancers. However, the impact of patient travel distance to health care on stage at diagnosis has not been well characterized. Methods This study used a historical cohort of patients with colon cancer in the National Cancer Data Base from 2003 through 2010. The primary outcome, stage at diagnosis, was evaluated using hierarchical regression modeling. A secondary outcome was time to receipt of initial therapy that was evaluated using Cox shared frailty modeling. Results Among 296,474 patients with colon cancer (mean age, 68 ± 13.6 years; 47.6% male; 78.5% white), 3.9% traveled ≥ 50 miles to the diagnosing facility. Fewer black patients, patients with higher income, and patients with lower education traveled longer distances (trend test P < .001 for all). Patients traveling ≥ 50 miles were more likely to present with metastatic disease compared with those traveling less than 12.5 miles (odds ratio [OR], 1.18; 95% CI, 1.12 to 1.24) or 12.5 to 49.9 miles (OR, 1.18; 95% CI, 1.12 to 1.24). In sensitivity analyses, the association was robust to alternate methods of modeling travel distance (quintile stratification or continuous). Travel distance ≥ 50 miles was also associated with a higher likelihood of earlier initiation of therapy compared with travel distance of less than 12.5 miles (hazard ratio [HR], 1.10; 95% CI, 1.08 to 1.13) or 12.5 to 49.9 miles (HR, 1.11; 95% CI, 1.08 to 1.13). Conclusion Advanced colon cancer stage at diagnosis is associated with patient travel distance to health care, which may be a barrier to early cancer screening. Health care reform efforts designed to address only insurance coverage may not mitigate disparities based on difficulties accessing cancer care. PMID:24516014
Supersonic transport grid generation, validation, and optimization
NASA Technical Reports Server (NTRS)
Aaronson, Philip G.
1995-01-01
The ever present demand for reduced flight times has renewed interest in High Speed Civil Transports (HSCT). The need for an HSCT becomes especially apparent when the long distance, over-sea, high growth Pacific rim routes are considered. Crucial to any successful HSCT design are minimal environmental impact and economic viability. Vital is the transport's aerodynamic efficiency, ultimately effecting both the environmental impact and the operating cost. Optimization, including numerical optimization, coupled with the use of computational fluid dynamics (CFD) technology, has and will offer a significant improvement beyond traditional methods.
A Window into Longer Lasting Batteries
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2016-11-29
There’s a new tool in the push to engineer rechargeable batteries that last longer and charge more quickly. An X-ray microscopy technique recently developed at Berkeley Lab has given scientists the ability to image nanoscale changes inside lithium-ion battery particles as they charge and discharge. The real-time images provide a new way to learn how batteries work, and how to improve them. The method was developed at Berkeley Lab’s Advanced Light Source, a DOE Office of Science User Facility, by a team of researchers from the Department of Energy’s SLAC National Accelerator Laboratory, Berkeley Lab, Stanford University, and other institutions.
Functional Analysis of Arabidopsis Sucrose Transporters
DOE Office of Scientific and Technical Information (OSTI.GOV)
John M. Ward
2009-03-31
Sucrose is the main photosynthetic product that is transported in the vasculature of plants. The long-distance transport of carbohydrates is required to support the growth and development of net-importing (sink) tissues such as fruit, seeds and roots. This project is focused on understanding the transport mechanism sucrose transporters (SUTs). These are proton-coupled sucrose uptake transporters (membrane proteins) that are required for transport of sucrose in the vasculature and uptake into sink tissues. The accomplishments of this project included: 1) the first analysis of substrate specificity for any SUT. This was accomplished using electrophysiology to analyze AtSUC2, a sucrose transporter frommore » companion cells in Arabidopsis. 2) the first analysis of the transport activity for a monocot SUT. The transport kinetics and substrate specificity of HvSUT1 from barley were studied. 3) the first analysis of a sucrose transporter from sugarcane. and 4) the first analysis of transport activity of a sugar alcohol transporter homolog from plants, AtPLT5. During this period four primary research papers, funded directly by the project, were published in refereed journals. The characterization of several sucrose transporters was essential for the current effort in the analysis of structure/function for this gene family. In particular, the demonstration of strong differences in substrate specificity between type I and II SUTs was important to identify targets for site-directed mutagenesis.« less
Making Distance Visible: Assembling Nearness in an Online Distance Learning Programme
ERIC Educational Resources Information Center
Ross, Jen; Gallagher, Michael Sean; Macleod, Hamish
2013-01-01
Online distance learners are in a particularly complex relationship with the educational institutions they belong to (Bayne, Gallagher, & Lamb, 2012). For part-time distance students, arrivals and departures can be multiple and invisible as students take courses, take breaks, move into independent study phases of a programme, find work or…
Kaliyev, Rymbay; Kapyshev, Timur; Goncharov, Alex; Lesbekov, Timur; Pya, Yuri
2015-01-01
Use of extracorporeal membrane oxygenation (ECMO) for severe cardiopulmonary failure has increased because of improved outcomes. A specially designed ECMO transport system allows for safe transport of patients over long distances. We report a 28-year-old pregnant woman (26 weeks gestation) with acute respiratory distress syndrome in whom ECMO support was necessary for survival, and she was transported to another facility 1,155 km away with the aid of the portable ECMO system. Transport was uneventful, and the patient's condition remained stable. Acute respiratory distress syndrome improved gradually until the patient was discharged from the hospital with excellent maternal and fetal outcome.
Artés, Juan M; Díez-Pérez, Ismael; Sanz, Fausto; Gorostiza, Pau
2011-03-22
We present a method to measure directly and at the single-molecule level the distance decay constant that characterizes the rate of electron transfer (ET) in redox proteins. Using an electrochemical tunneling microscope under bipotentiostatic control, we obtained current−distance spectroscopic recordings of individual redox proteins confined within a nanometric tunneling gap at a well-defined molecular orientation. The tunneling current decays exponentially, and the corresponding decay constant (β) strongly supports a two-step tunneling ET mechanism. Statistical analysis of decay constant measurements reveals differences between the reduced and oxidized states that may be relevant to the control of ET rates in enzymes and biological electron transport chains.
Ponisovskiy, M R
2011-01-01
The article presents mechanisms of cell metabolism, cell development, cell activity, and maintenance of cellular stability. The literature is reviewed from the point of view of these concepts. The balance between anabolic and catabolic processes induces chemical potentials in the extracellular and intracellular media. The chemical potentials of these media are defined as the driving forces of both passive and active transport of substances across cellular membranes. The driving forces of substance transport across cellular membranes as in cellular metabolism and in immune responses and hormonal expressions are considered in the biochemical and biophysical models, reflecting the mechanisms for maintenance of stability of the internal medium and internal energy of an organism. The interactions of passive transport and active transport of substances across cellular walls promote cell proliferation, as well as the mechanism of cellular capacitors, promoting remote reactions across distance for hormonal expression and immune responses. The offered concept of cellular capacitors has given the possibility to explain the mechanism of remote responses of cells to new situations, resulting in the appearance of additional agents. The biophysical model develops an explanation of some cellular functions: cellular membrane action have been identified with capacitor action, based on the similarity of the structures and as well as on similarity of biophysical properties of electric data that confirm the action of the compound-specific interactions of cells within an organism, promoting hormonal expressions and immune responses to stabilize the thermodynamic system of an organism. Comparison of a cellular membrane action to a capacitor has given the possibility for the explanations of exocytosis and endocytosis mechanisms, internalization of the receptor-ligand complex, selection as a receptor reaction to a ligand by immune responses or hormonal effects, reflecting cellular
Variations in Transport Derived from Satellite Altimeter Data over the Gulf Stream
NASA Technical Reports Server (NTRS)
Molinelli, Eugene; Lambert, Richard B., Jr.
1981-01-01
Variations in total change of sea surface height (delta h) across the Gulf Stream are observed using Seasat radar altimeter data. The sea surface height is related to transport within the stream by a two layer model. Variations in delta h are compared with previously observed changes in transport found to increase with distance downstream. No such increase is apparent since the satellite transports show no significant dependence on distance. Though most discrepancies are less than 50 percent, a few cases differ by about 100 percent and more. Several possible reasons for these discrepancies are advanced, including geoid error, but only two oceanographic contributions to the variability are examined, namely, limitations in the two layer model and meanders in the current. It is concluded that some of the discrepancies could be explained as changes in the density structure not accounted for by the two layer model.
Theoretical Principles of Distance Education.
ERIC Educational Resources Information Center
Keegan, Desmond, Ed.
This book contains the following papers examining the didactic, academic, analytic, philosophical, and technological underpinnings of distance education: "Introduction"; "Quality and Access in Distance Education: Theoretical Considerations" (D. Randy Garrison); "Theory of Transactional Distance" (Michael G. Moore);…
NASA Astrophysics Data System (ADS)
McQuinn, Kristen. B. W.; Skillman, Evan D.; Dolphin, Andrew E.; Berg, Danielle; Kennicutt, Robert
2016-07-01
Great investments of observing time have been dedicated to the study of nearby spiral galaxies with diverse goals ranging from understanding the star formation process to characterizing their dark matter distributions. Accurate distances are fundamental to interpreting observations of these galaxies, yet many of the best studied nearby galaxies have distances based on methods with relatively large uncertainties. We have started a program to derive accurate distances to these galaxies. Here we measure the distance to M51—the Whirlpool galaxy—from newly obtained Hubble Space Telescope optical imaging using the tip of the red giant branch method. We measure the distance modulus to be 8.58 ± 0.10 Mpc (statistical), corresponding to a distance modulus of 29.67 ± 0.02 mag. Our distance is an improvement over previous results as we use a well-calibrated, stable distance indicator, precision photometry in a optimally selected field of view, and a Bayesian Maximum Likelihood technique that reduces measurement uncertainties. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.
Exploring Ways of Influencing Transport Behaviors by Using Telecommunications Technologies
DOT National Transportation Integrated Search
2004-06-01
Information technology can facilitate substitution and modification of transportation behaviors. Distance Learning (DL) can replace library work, meetings, and some traditional face-to-face class meetings. For off-campus full-time students, and for p...
Distance learning in academic health education.
Mattheos, N; Schittek, M; Attström, R; Lyon, H C
2001-05-01
Distance learning is an apparent alternative to traditional methods in education of health care professionals. Non-interactive distance learning, interactive courses and virtual learning environments exist as three different generations in distance learning, each with unique methodologies, strengths and potential. Different methodologies have been recommended for distance learning, varying from a didactic approach to a problem-based learning procedure. Accreditation, teamwork and personal contact between the tutors and the students during a course provided by distance learning are recommended as motivating factors in order to enhance the effectiveness of the learning. Numerous assessment methods for distance learning courses have been proposed. However, few studies report adequate tests for the effectiveness of the distance-learning environment. Available information indicates that distance learning may significantly decrease the cost of academic health education at all levels. Furthermore, such courses can provide education to students and professionals not accessible by traditional methods. Distance learning applications still lack the support of a solid theoretical framework and are only evaluated to a limited extent. Cases reported so far tend to present enthusiastic results, while more carefully-controlled studies suggest a cautious attitude towards distance learning. There is a vital need for research evidence to identify the factors of importance and variables involved in distance learning. The effectiveness of distance learning courses, especially in relation to traditional teaching methods, must therefore be further investigated.
Coe, Jeffrey A.; Reid, Mark E.; Brien, Dainne L.; Michael, John A.
2011-01-01
To better understand controls on debris-flow entrainment and travel distance, we examined topographic and drainage network characteristics of initiation locations in two separate debris-flow prone areas located 700 km apart along the west coast of the U.S. One area was located in northern California, the other in southern Oregon. In both areas, debris flows mobilized from slides during large storms, but, when stratified by number of contributing initiation locations, median debris-flow travel distances in Oregon were 5 to 8 times longer than median distances in California. Debris flows in Oregon readily entrained channel material; entrainment in California was minimal. To elucidate this difference, we registered initiation locations to high-resolution airborne LiDAR, and then examined travel distances with respect to values of slope, upslope contributing area, planform curvature, distance from initiation locations to the drainage network, and number of initiation areas that contributed to flows. Results show distinct differences in the topographic and drainage network characteristics of debris-flow initiation locations between the two study areas. Slope and planform curvature of initiation locations (landslide headscarps), commonly used to predict landslide-prone areas, were not useful for predicting debris-flow travel distances. However, a positive, power-law relation exists between median debris-flow travel distance and the number of contributing debris-flow initiation locations. Moreover, contributing area and the proximity of the initiation locations to the drainage network both influenced travel distances, but proximity to the drainage network was the better predictor of travel distance. In both study areas, flows that interacted with the drainage network flowed significantly farther than those that did not. In California, initiation sites within 60 m of the network were likely to reach the network and generate longtraveled flows; in Oregon, the threshold was
The structure of turbulent channel flow with passive scalar transport
NASA Technical Reports Server (NTRS)
Guezennec, Y.; Stretch, D.; Kim, J.
1990-01-01
The simulation of turbulent channel flow, with various passive markers, was examined to investigate the local mechanisms of passive scalar transport. We found significant differences between the local transport of heat and momentum, even when the molecular and turbulent Prandtl numbers are of order one. These discrepancies can be attributed to the role of the pressure. We also found that the heat is a poor marker of the vorticity field outside of the near wall region and that scalar transport over significant distances results from the aggregate effect of many turbulent eddies.
Longshore Sediment Transport Rate Calculated Incorporating Wave Orbital Velocity Fluctuations
2006-09-01
distribution of longshore sediment transport in the surf zone is necessary in the design and planning of groins, jetties, weirs and pipeline landfalls...transported by any current. Breaker height is defined as the vertical distance between the wave crest and the preceding wave trough at incipient...terminology; spilling breakers occur if the wave crest becomes unstable and flows down the front face of the wave producing a foamy water surface; plunging
Estimating rupture distances without a rupture
Thompson, Eric M.; Worden, Charles
2017-01-01
Most ground motion prediction equations (GMPEs) require distances that are defined relative to a rupture model, such as the distance to the surface projection of the rupture (RJB) or the closest distance to the rupture plane (RRUP). There are a number of situations in which GMPEs are used where it is either necessary or advantageous to derive rupture distances from point-source distance metrics, such as hypocentral (RHYP) or epicentral (REPI) distance. For ShakeMap, it is necessary to provide an estimate of the shaking levels for events without rupture models, and before rupture models are available for events that eventually do have rupture models. In probabilistic seismic hazard analysis, it is often convenient to use point-source distances for gridded seismicity sources, particularly if a preferred orientation is unknown. This avoids the computationally cumbersome task of computing rupture-based distances for virtual rupture planes across all strikes and dips for each source. We derive average rupture distances conditioned on REPI, magnitude, and (optionally) back azimuth, for a variety of assumed seismological constraints. Additionally, we derive adjustment factors for GMPE standard deviations that reflect the added uncertainty in the ground motion estimation when point-source distances are used to estimate rupture distances.
Groothuis, Dennis R; Vavra, Michael W; Schlageter, Kurt E; Kang, Eric W-Y; Itskovich, Andrea C; Hertzler, Shannon; Allen, Cathleen V; Lipton, Howard L
2007-01-01
We examined the roles of diffusion, convection and capillary transporters in solute removal from extracellular space (ECS) of the brain. Radiolabeled solutes (eight with passive distribution and four with capillary or cell transporters) were injected into the brains of rats (n=497) and multiple-time point experiments measured the amount remaining in brain as a function of time. For passively distributed compounds, there was a relationship between lipid:water solubility and total brain efflux:diffusional efflux, which dominated when k(p), the transcapillary efflux rate constant, was >10(0) h(-1); when 10(-1)
Kannan, Ravishekar; Guo, Peng; Przekwas, Andrzej
2016-06-01
This paper is the first in a series wherein efficient computational methods are developed and implemented to accurately quantify the transport, deposition, and clearance of the microsized particles (range of interest: 2 to 10 µm) in the human respiratory tract. In particular, this paper (part I) deals with (i) development of a detailed 3D computational finite volume mesh comprising of the NOPL (nasal, oral, pharyngeal and larynx), trachea and several airway generations; (ii) use of CFD Research Corporation's finite volume Computational Biology (CoBi) flow solver to obtain the flow physics for an oral inhalation simulation; (iii) implement a novel and accurate nodal inverse distance weighted Eulerian-Lagrangian formulation to accurately obtain the deposition, and (iv) development of Wind-Kessel boundary condition algorithm. This new Wind-Kessel boundary condition algorithm allows the 'escaped' particles to reenter the airway through the outlets, thereby to an extent accounting for the drawbacks of having a finite number of lung generations in the computational mesh. The deposition rates in the NOPL, trachea, the first and second bifurcation were computed, and they were in reasonable accord with the Typical Path Length model. The quantitatively validated results indicate that these developments will be useful for (i) obtaining depositions in diseased lungs (because of asthma and COPD), for which there are no empirical models, and (ii) obtaining the secondary clearance (mucociliary clearance) of the deposited particles. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
NASA Technical Reports Server (NTRS)
1991-01-01
This report discusses the design and marketability of a next generation supersonic transport. Apogee Aeronautics Corporation has designated its High Speed Civil Transport (HSCT): Supercruiser HS-8. Since the beginning of the Concorde era, the general consensus has been that the proper time for the introduction of a next generation Supersonic Transport (SST) would depend upon the technical advances made in the areas of propulsion (reduction in emissions) and material composites (stronger, lighter materials). It is believed by many in the aerospace industry that these beforementioned technical advances lie on the horizon. With this being the case, this is the proper time to begin the design phase for the next generation HSCT. The design objective for a HSCT was to develop an aircraft that would be capable of transporting at least 250 passengers with baggage at a distance of 5500 nmi. The supersonic Mach number is currently unspecified. In addition, the design had to be marketable, cost effective, and certifiable. To achieve this goal, technical advances in the current SST's must be made, especially in the areas of aerodynamics and propulsion. As a result of these required aerodynamic advances, several different supersonic design concepts were reviewed.
Charge transport through DNA based electronic barriers
NASA Astrophysics Data System (ADS)
Patil, Sunil R.; Chawda, Vivek; Qi, Jianqing; Anantram, M. P.; Sinha, Niraj
2018-05-01
We report charge transport in electronic 'barriers' constructed by sequence engineering in DNA. Considering the ionization potentials of Thymine-Adenine (AT) and Guanine-Cytosine (GC) base pairs, we treat AT as 'barriers'. The effect of DNA conformation (A and B form) on charge transport is also investigated. Particularly, the effect of width of 'barriers' on hole transport is investigated. Density functional theory (DFT) calculations are performed on energy minimized DNA structures to obtain the electronic Hamiltonian. The quantum transport calculations are performed using the Landauer-Buttiker framework. Our main findings are contrary to previous studies. We find that a longer A-DNA with more AT base pairs can conduct better than shorter A-DNA with a smaller number of AT base pairs. We also find that some sequences of A-DNA can conduct better than a corresponding B-DNA with the same sequence. The counterions mediated charge transport and long range interactions are speculated to be responsible for counter-intuitive length and AT content dependence of conductance of A-DNA.
Integration of geospatial multi-mode transportation Systems in Kuala Lumpur
NASA Astrophysics Data System (ADS)
Ismail, M. A.; Said, M. N.
2014-06-01
Public transportation serves people with mobility and accessibility to workplaces, health facilities, community resources, and recreational areas across the country. Development in the application of Geographical Information Systems (GIS) to transportation problems represents one of the most important areas of GIS-technology today. To show the importance of GIS network analysis, this paper highlights the determination of the optimal path between two or more destinations based on multi-mode concepts. The abstract connector is introduced in this research as an approach to integrate urban public transportation in Kuala Lumpur, Malaysia including facilities such as Light Rapid Transit (LRT), Keretapi Tanah Melayu (KTM) Komuter, Express Rail Link (ERL), KL Monorail, road driving as well as pedestrian modes into a single intelligent data model. To assist such analysis, ArcGIS's Network Analyst functions are used whereby the final output includes the total distance, total travelled time, directional maps produced to find the quickest, shortest paths, and closest facilities based on either time or distance impedance for multi-mode route analysis.
Bonanni, Pablo Sebastián; Massazza, Diego; Busalmen, Juan Pablo
2013-07-07
Geobacter sulfurreducens bacteria grow on biofilms and have the particular ability of using polarized electrodes as the final electron acceptor of their respiratory chain. In these biofilms, electrons are transported through distances of more than 50 μm before reaching the electrode. The way in which electrons are transported across the biofilm matrix through such large distances remains under intense discussion. None of the two mechanisms proposed for explaining the process, electron hopping through outer membrane cytochromes and metallic like conduction through conductive PilA filaments, can account for all the experimental evidence collected so far. Aiming at providing new elements for understanding the basis for electron transport, in this perspective article we present a modelled structure of Geobacter pilus. Its analysis in combination with already existing experimental evidence gives support to the proposal of the "stepping stone" mechanism, in which the combined action of pili and cytochromes allows long range electron transport through the biofilm.
Air medical transportation in India: Our experience.
Khurana, Himanshu; Mehta, Yatin; Dubey, Sunil
2016-01-01
Long distance air travel for medical needs is on the increase worldwide. The condition of some patients necessitates specially modified aircraft, and monitoring and interventions during transport by trained medical personnel. This article presents our experience in domestic and international interhospital air medical transportation from January 2010 to January 2014. Hospital records of all air medical transportation undertaken to the institute during the period were analyzed for demographics, primary etiology, and events during transport. 586 patients, 453 (77.3%) males and 133 (22.6%) females of ages 46.7 ± 12.6 years and 53.4 ± 9.7 years were transported by us to the institute. It took 3030 flying hours with an average of 474 ± 72 min for each mission. The most common indication for transport was cardiovascular diseases in 210 (35.8%) and central nervous system disease in 120 (20.4%) cases. The overall complication rate was 5.3% There was no transport related mortality. Cardiac and central nervous system ailments are the most common indication for air medical transportation. These patients may need attention and interventions as any critical patient in the hospital but in a difficult environment lacking space and help. Air medical transport carries no more risk than ground transportation.
Atomic weights: no longer constants of nature
Coplen, Tyler B.; Holden, Norman E.
2011-01-01
Many of us were taught that the standard atomic weights we found in the back of our chemistry textbooks or on the Periodic Table of the Chemical Elements hanging on the wall of our chemistry classroom are constants of nature. This was common knowledge for more than a century and a half, but not anymore. The following text explains how advances in chemical instrumentation and isotopic analysis have changed the way we view atomic weights and why they are no longer constants of nature
Does size and buoyancy affect the long-distance transport of floating debris?
NASA Astrophysics Data System (ADS)
Ryan, Peter G.
2015-08-01
Floating persistent debris, primarily made from plastic, disperses long distances from source areas and accumulates in oceanic gyres. However, biofouling can increase the density of debris items to the point where they sink. Buoyancy is related to item volume, whereas fouling is related to surface area, so small items (which have high surface area to volume ratios) should start to sink sooner than large items. Empirical observations off South Africa support this prediction: moving offshore from coastal source areas there is an increase in the size of floating debris, an increase in the proportion of highly buoyant items (e.g. sealed bottles, floats and foamed plastics), and a decrease in the proportion of thin items such as plastic bags and flexible packaging which have high surface area to volume ratios. Size-specific sedimentation rates may be one reason for the apparent paucity of small plastic items floating in the world’s oceans.
de Melo, Gileno Edu Lameira; Kleiner, Ana Francisca Rozin; Lopes, Jamile Benite Palma; Dumont, Arislander Jonathan Lopes; Lazzari, Roberta Delasta; Galli, Manuela; Oliveira, Claudia Santos
2018-04-07
To evaluate the effects of gait training with virtual reality (VR) on walking distance and physical fitness in individuals with Parkinson's Disease (PD). Thirty-seven individuals with PD participated in this prospective, randomized, controlled clinical trial. They were randomly allocated to a control group submitted to conventional training (n = 12), a treadmill group submitted to gait training on a treadmill (n = 13) and a VR group submitted to gait training using the XboxTM (n = 12). Clinical measures, gait variables and the Six-Minute Walk Test (6MWT) were evaluated: pre-intervention, after one intervention session, post-intervention and follow up (30 days after intervention). The VR and treadmill groups travelled longer distances on the 6MWT and had faster gait speed in comparison to the control group. The VR and treadmill groups demonstrated an increase in pre-6MWT HR. The VR group had more intense HR after the first session and throughout training, but these gains were not maintained at the follow-up. The present findings demonstrate that gait training with a VR program is as effective as treadmill training with regard to gains in walking distance and improvements in temporal gait variables in individuals with PD.
Mossotti, Regina H; Baskir, Eli A; Kozlowski, Corinne P; Franklin, Ashley D; Feldhamer, George A; Asa, Cheryl S
2018-06-13
Understanding the factors used by female cheetahs (Acinonyx jubatus) to make mate choice decisions could benefit zoo breeding programs, which currently assign mates based primarily on genetic distance. Because transporting animals between institutions is costly and can be stressful, females are often limited in the number of males available for mating. One solution would be to determine if an easily transported substance could be used to gauge interest by a female to a potential mate. Here, we investigate female interest in urine samples from males of different genetic distances. Twelve females at five institutions were offered scents from 17 males of varying genetic relatedness in a pair-wise choice paradigm. Behavioral responses of the females were recorded to determine preference. Results showed that females spent more time sniffing and in proximity to scents from the most distantly related males, but female response was not influenced by male urine testosterone concentration, female parity, age, or estrous cycling. Further research will be necessary to determine whether a female's interest in male urine translates to mate preference and acceptance before this technique can be applied to zoo breeding programs. © 2018 Wiley Periodicals, Inc.
Formal Alternative Transportation Options for Older Adults: An Assessment of Need.
Turner, Joshua J; Adams-Price, Carolyn E; Strawderman, Lesley
2017-01-01
This study measured the need for formal alternative modes of transportation among older adults by applying traditional factors of the Behavioral Model. Survey participants who regularly drove were compared to those who could no longer drive. Race/ethnicity and self-reported health were significant predictors of perceived need for transportation services for both groups. However, income and service awareness were significant predictors only for drivers, while family proximity was a significant predictor only for non-drivers. Results suggest the importance of gaining a better understanding of the factors associated with need for senior-focused transportation services to more effectively plan such programs.
ERIC Educational Resources Information Center
Moeglin, Pierre; Vidal, Martine
2015-01-01
The purpose of this review, spanning over 12 years of publication of "Distances et Médiations des Savoirs" ("DMS"), formerly "Distance et Savoirs" ("DMS") (2003-2014), is guided by the question why and how French-speaking researchers addressed the issues of time, workload and costs in distance learning, and…
Revisiting Academic Capitalism in Canada: No Longer the Exception
ERIC Educational Resources Information Center
Metcalfe, Amy Scott
2010-01-01
In "Academic Capitalism: Politics, Policies, and the Entrepreneurial University" (1997), Slaughter and Leslie found that Canada showed signs of resisting academic capitalism. Changes in postsecondary education funding policies and the emergence of new commercialization initiatives are evidence that Canada is certainly no longer, and…
Distance Education in the Health Sciences. Readings in Distance Education, Number 8.
ERIC Educational Resources Information Center
Moore, Michael G. Ed.; Savrock, Joseph T., Ed.
This document contains 17 papers on distance education in the health sciences. The following papers are included: "Preface: Distance Education in the Health Professions: A Collection of Research" (Michael G. Moore); "A Historical Overview of Telecommunications in the Health Care Industry" (Joseph S. Anderson); "Distance…
Motor fatigue measurement by distance-induced slow down of walking speed in multiple sclerosis.
Phan-Ba, Rémy; Calay, Philippe; Grodent, Patrick; Delrue, Gael; Lommers, Emilie; Delvaux, Valérie; Moonen, Gustave; Belachew, Shibeshih
2012-01-01
Motor fatigue and ambulation impairment are prominent clinical features of people with multiple sclerosis (pMS). We hypothesized that a multimodal and comparative assessment of walking speed on short and long distance would allow a better delineation and quantification of gait fatigability in pMS. Our objectives were to compare 4 walking paradigms: the timed 25-foot walk (T25FW), a corrected version of the T25FW with dynamic start (T25FW(+)), the timed 100-meter walk (T100MW) and the timed 500-meter walk (T500MW). Thirty controls and 81 pMS performed the 4 walking tests in a single study visit. The 4 walking tests were performed with a slower WS in pMS compared to controls even in subgroups with minimal disability. The finishing speed of the last 100-meter of the T500MW was the slowest measurable WS whereas the T25FW(+) provided the fastest measurable WS. The ratio between such slowest and fastest WS (Deceleration Index, DI) was significantly lower only in pMS with EDSS 4.0-6.0, a pyramidal or cerebellar functional system score reaching 3 or a maximum reported walking distance ≤ 4000 m. The motor fatigue which triggers gait deceleration over a sustained effort in pMS can be measured by the WS ratio between performances on a very short distance and the finishing pace on a longer more demanding task. The absolute walking speed is abnormal early in MS whatever the distance of effort when patients are unaware of ambulation impairment. In contrast, the DI-measured ambulation fatigability appears to take place later in the disease course.
Distance Teacher Education in Pakistan
ERIC Educational Resources Information Center
Jumani, Nabi Bux; Zai, Zafar Iqbal Yousuf
2009-01-01
Distance education means instruction in which the instructor and student are separated by distance and interact through the assistance of communication technology. Distance education changes the learning relationship from the common, centralized school model to a more decentralized, flexible model. It also reverses social dynamics by bringing…
Green, Adam E; Kraemer, David J M; Fugelsang, Jonathan A; Gray, Jeremy R; Dunbar, Kevin N
2010-01-01
Solving problems often requires seeing new connections between concepts or events that seemed unrelated at first. Innovative solutions of this kind depend on analogical reasoning, a relational reasoning process that involves mapping similarities between concepts. Brain-based evidence has implicated the frontal pole of the brain as important for analogical mapping. Separately, cognitive research has identified semantic distance as a key characteristic of the kind of analogical mapping that can support innovation (i.e., identifying similarities across greater semantic distance reveals connections that support more innovative solutions and models). However, the neural substrates of semantically distant analogical mapping are not well understood. Here, we used functional magnetic resonance imaging (fMRI) to measure brain activity during an analogical reasoning task, in which we parametrically varied the semantic distance between the items in the analogies. Semantic distance was derived quantitatively from latent semantic analysis. Across 23 participants, activity in an a priori region of interest (ROI) in left frontopolar cortex covaried parametrically with increasing semantic distance, even after removing effects of task difficulty. This ROI was centered on a functional peak that we previously associated with analogical mapping. To our knowledge, these data represent a first empirical characterization of how the brain mediates semantically distant analogical mapping.
Determining Usability Versus Cost and Yields of a Regional Transport
NASA Technical Reports Server (NTRS)
Gvozdenovic, Slobodan
1999-01-01
Regional transports are designed to operate on air networks having the basic characteristics of short trip distances and low density passengers/cargo, i.e. small numbers of passengers per flight. Regional transports passenger capacity is from 10 to 100 seats and operate on routes from 350 to 1000 nautical miles (nm). An air network operated by regional transports has the following characteristics: (1) connecting regional centers; (2) operating on low density passengers/cargo flow services with minimum two frequencies per day; (3) operating on high density passengers/cargo flow with more than two frequencies per day; and (4) operating supplemental services whenever market demands in order to help bigger capacity aircraft already operating the same routes. In order to meet passenger requirements providing low fares and high or required number of frequencies, airlines must constantly monitor operational costs and keep them low. It is obvious that costs of operating aircraft must be lower than yield obtained by transporting passengers and cargo. The requirement to achieve favorable yield/cost ratio must provide the answer to the question of which aircraft will best meet a specific air network. An air network is defined by the number of services, the trip distance of each service, and the number of flights (frequencies) per day and week.
NASA Astrophysics Data System (ADS)
Most, Sebastian; Nowak, Wolfgang; Bijeljic, Branko
2015-04-01
Fickian transport in groundwater flow is the exception rather than the rule. Transport in porous media is frequently simulated via particle methods (i.e. particle tracking random walk (PTRW) or continuous time random walk (CTRW)). These methods formulate transport as a stochastic process of particle position increments. At the pore scale, geometry and micro-heterogeneities prohibit the commonly made assumption of independent and normally distributed increments to represent dispersion. Many recent particle methods seek to loosen this assumption. Hence, it is important to get a better understanding of the processes at pore scale. For our analysis we track the positions of 10.000 particles migrating through the pore space over time. The data we use come from micro CT scans of a homogeneous sandstone and encompass about 10 grain sizes. Based on those images we discretize the pore structure and simulate flow at the pore scale based on the Navier-Stokes equation. This flow field realistically describes flow inside the pore space and we do not need to add artificial dispersion during the transport simulation. Next, we use particle tracking random walk and simulate pore-scale transport. Finally, we use the obtained particle trajectories to do a multivariate statistical analysis of the particle motion at the pore scale. Our analysis is based on copulas. Every multivariate joint distribution is a combination of its univariate marginal distributions. The copula represents the dependence structure of those univariate marginals and is therefore useful to observe correlation and non-Gaussian interactions (i.e. non-Fickian transport). The first goal of this analysis is to better understand the validity regions of commonly made assumptions. We are investigating three different transport distances: 1) The distance where the statistical dependence between particle increments can be modelled as an order-one Markov process. This would be the Markovian distance for the process, where