636 research outputs found
Ingestion of Carbohydrate Prior to and during Maximal, Sprint Interval Cycling Has No Ergogenic Effect: A Randomized, Double-Blind, Placebo Controlled, Crossover Study
Carbohydrate (CHO) ingestion may improve intermittent sprint performance in repeated sprint efforts ≤15 s. Yet, evidence for its efficacy on sprint interval durations ~30 s is lacking. The purpose of this study was to investigate the effects of CHO ingestion on maximal sprint interval exercise. Fifteen (n = 15) recreational athletes (13/2 males/females, age 22 ± 2 years; height 176 ± 11 cm; mass 76.8 ± 11.3 kg) volunteered for this randomised, double-blind, placebo-controlled, crossover design. Participants completed two experimental trials (performed 10-days apart) involving the ingestion of an 8% CHO solution or a flavour and appearance-matched placebo (PLA) solution (5 mL/kg/bw), immediately before exercise, and preceding the second interval of four × 30 s bouts of repeated maximal sprint efforts (separated by 3.5 min of passive recovery). Peak and mean power (W) output progressively decreased during the repeated sprints (main effect of time, p < 0.0001), but there were no differences between CHO and PLA during any of the sprints (p > 0.05 for condition main effect and condition × time interaction). Physiological responses (blood lactate, heart rate, oxygen consumption, respiratory exchange ratio and RPE) were also unaltered by CHO ingestion. In conclusion, CHO ingestion does not enhance performance or modulate physiological responses during intermittent maximal, sprint cycling
Using Eye Tracking and Electroencephalography to Understand the Efficacy of Digital and Static Outdoor Advertisements
Abstract de la ponencia[EN] This study discusses the contributions of advanced eye tracking research
combined with electroencephalography (EEG) as a method of understanding
the cognitive processing of digital vs. static outdoor advertisements. Subjects
were exposed to a variety of billboard advertisements on a section of
Interstate freeway in a suburban area in the western United States. Results
showed that visual fixation time was higher for digital advertisements
compared to static advertisements. In particular, the eye-tracking data
revealed which advertisements received the most attention. This was mainly
dependent upon location (i.e. distance from driver, distance from adjacent
traffic signs, etc.).
As eye-tracking systems have become more sophisticated and affordable,
there has been an increasing interest in the use of eye tracking within the
traffic safety and outdoor advertising domain (Perez & Bertola, 2010). Eye
tracking studies that have focused on web-based and driving stimuli have
gathered eye-movement data while participants were engaged in lowattention
settings (Lee and Ahn, 2012). The findings of these studies have
indicated that digital and animated advertisements, in low attention settings,
reduce the likelihood of mental recall and result in overall decreased
cognitive engagement.
Twenty-five subjects between the ages of 18 and 45 participated in the study.
A 16 mile (25.75 kilometer) freeway drive was videotaped and then projected
onto a four-by-six-foot screen. Subjects then viewed the projected video from
inside a stationary car to simulate a driving environment. Using Tobii2
Glasses eye tracking system, subjectsâ eye-movements and gaze patterns were
recorded during the simulation. EEG data was also collected to measure the
subjectâs emotional response, and to gain additional insight into how they felt
about the advertisements. In addition, participants were asked immediately
after their drive to list any advertisements they recalled.
These findings provide indications for best practices of effective outdoor
advertising using gaze pattern analysis. These include positioning, layout,
color schemes, etc. A potential implication for digital advertisements could
be identifying the optimal length of time to display digital signage.
Additionally, the results may suggest improvements in specific industry ads in
order to maximize cognitive influence on consumer action (e.g. best times to
display food and beverage advertisements).
From a traffic safety consideration, these results will provide a psychological
understanding of whether or not outdoor advertisements present safety
implications to drivers. Overall, findings provide a better understanding of
digital and static outdoor advertising as it relates to safety and consumer
behavior. The results of this study may have significant implications in both
the private and public sectors.Reas, B.; Dishman, P.; Mc Carter, A.; Jolley, AD. (2016). Using Eye Tracking and Electroencephalography to Understand the Efficacy of Digital and Static Outdoor Advertisements. En CARMA 2016: 1st International Conference on Advanced Research Methods in Analytics. Editorial Universitat PolitĂšcnica de ValĂšncia. 168-169. https://doi.org/10.4995/CARMA2016.2015.3109OCS16816
A method for eternally dominating strong grids
International audienceIn the eternal domination game, an attacker attacks a vertex at each turn and a team of guards must move a guard to the attacked vertex to defend it. The guards may only move to adjacent vertices and no more than one guard may occupy a vertex. The goal is to determine the eternal domination number of a graph which is the minimum number of guards required to defend the graph against an infinite sequence of attacks. In this paper, we continue the study of the eternal domination game on strong grids. Cartesian grids have been vastly studied with tight bounds for small grids such as 2Ăn, 3Ăn, 4Ăn, and 5Ăn grids, and recently it was proven in [Lamprou et al., CIAC 2017, 393-404] that the eternal domination number of these grids in general is within O(m + n) of their domination number which lower bounds the eternal domination number. Recently, Finbow et al. proved that the eternal domination number of strong grids is upper bounded by mn 6 + O(m + n). We adapt the techniques of [Lamprou et al., CIAC 2017, 393-404] to prove that the eternal domination number of strong grids is upper bounded by mn 7 + O(m + n). While this does not improve upon a recently announced bound of âĄm/3†xâĄn/3†+ O(m â n) [Mc Inerney, Nisse, PĂ©rennes, HAL archives, 2018; Mc Inerney, Nisse, PĂ©rennes, CIAC 2019] in the general case, we show that our bound is an improvement in the case where the smaller of the two dimensions is at most 6179
Ergonomic Evaluation on Skidding Tractors
Choroid plexus epithelial cells (CPECs) secrete cerebrospinal fluid (CSF). They express Na+-K+-ATPase and Na+-K+-2Clâ cotransporter 1 (NKCC1) on their apical membrane, deviating from typical basolateral membrane location in secretory epithelia. Given this peculiarity, the direction of basal net ion fluxes mediated by NKCC1 in CPECs is controversial, and cotransporter function is unclear. Determining the direction of basal NKCC1-mediated fluxes is critical to understanding the function of apical NKCC1. If NKCC1 works in the net efflux mode, it may be directly involved in CSF secretion. Conversely, if NKCC1 works in the net influx mode, it would have an absorptive function, contributing to intracellular Clâ concentration ([Clâ]i) and cell water volume (CWV) maintenance needed for CSF secretion. We resolve this long-standing debate by electron microscopy (EM), live-cell-imaging microscopy (LCIM), and intracellular Na+ and Clâ measurements in single CPECs of NKCC1+/+ and NKCC1â/â mouse. NKCC1-mediated ion and associated water fluxes are tightly linked, thus their direction is inferred by measuring CWV changes. Genetic or pharmacological NKCC1 inactivation produces CPEC shrinkage. EM of NKCC1â/â CPECs in situ shows they are shrunken, forming large dilations of their basolateral extracellular spaces, yet remaining attached by tight junctions. Normarski LCIM shows in vitro CPECs from NKCC1â/â are ~17% smaller than NKCC1+/+. CWV measurements in calcein-loaded CPECs show that bumetanide (10 ÎŒM) produces ~16% decrease in CWV in NKCC1+/+ but not in NKCC1â/â CPECs. Our findings suggest that under basal conditions apical NKCC1 is continuously active and works in the net inward flux mode maintaining [Clâ]i and CWV needed for CSF secretion
Atrazine and cancer incidence among pesticide applicators in the agricultural health study (1994-2007).
Atrazine is a triazine herbicide used widely in the United States. Although it is an animal carcinogen, the mechanism in rodents does not appear to operate in humans. Few epidemiologic studies have provided evidence for an association
Lead Speciation and Bioavailability in Apatite-Amended Sediments
The in situ sequestration of lead (Pb) in sediment with a phosphate amendment was investigated by Pb speciation and bioavailability. Sediment Pb in preamendment samples was identified as galena (PbS) with trace amounts of absorbed Pb. Sediment exposed to atmospheric conditions underwent conversion to hydrocerussite and anglesite. Sediments mixed with apatite exhibited limited conversion to pyromorphite, the hypothesized end product. Conversion of PbS to pyromorphite is inhibited under reducing conditions, and pyromorphite formation appears limited to reaction with pore water Pb and PbS oxidation products. Porewater Pb values were decreased by 94% or more when sediment was amended with apatite. The acute toxicity of the sediment Pb was evaluated with Hyalella azteca and bioaccumulation of Pb with Lumbriculus variegatus. The growth of H. azteca may be mildly inhibited in contaminated sediment, with apatite-amended sediments exhibiting on average a higher growth weight by approximately 20%. The bioaccumulation of Pb in L. variegatus tissue decreased with increased phosphate loading in contaminated sediment. The study indicates limited effectiveness of apatite in sequestering Pb if present as PbS under reducing conditions, but sequestration of porewater Pb and stabilization of near-surface sediment may be a feasible and alternative approach to decreasing potential toxicity of Pb
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