► Cell phone use while driving is prevalent among US teens and young adults. ► A driving simulator was used to measure traffic inefficiency and safety outcomes. ► Inefficiency while driving ...distracted may contribute to traffic congestion. ► Cell phone use while driving also led to diminished safety. ► Naturalistic study is needed to see if inefficiencies translate to real driving.
Studies have documented a link between distracted driving and diminished safety; however, an association between distracted driving and traffic congestion has not been investigated in depth. The present study examined the behavior of teens and young adults operating a driving simulator while engaged in various distractions (i.e., cell phone, texting, and undistracted) and driving conditions (i.e., free flow, stable flow, and oversaturation). Seventy five participants 16–25 years of age (split into 2 groups: novice drivers and young adults) drove a STISIM simulator three times, each time with one of three randomly presented distractions. Each drive was designed to represent daytime scenery on a 4 lane divided roadway and included three equal roadway portions representing Levels of Service (LOS) A, C, and E as defined in the 2000 Highway Capacity Manual. Participants also completed questionnaires documenting demographics and driving history. Both safety and traffic flow related driving outcomes were considered. A Repeated Measures Multivariate Analysis of Variance was employed to analyze continuous outcome variables and a Generalized Estimate Equation (GEE) Poisson model was used to analyze count variables. Results revealed that, in general more lane deviations and crashes occurred during texting. Distraction (in most cases, text messaging) had a significantly negative impact on traffic flow, such that participants exhibited greater fluctuation in speed, changed lanes significantly fewer times, and took longer to complete the scenario. In turn, more simulated vehicles passed the participant drivers while they were texting or talking on a cell phone than while undistracted. The results indicate that distracted driving, particularly texting, may lead to reduced safety and traffic flow, thus having a negative impact on traffic operations. No significant differences were detected between age groups, suggesting that all drivers, regardless of age, may drive in a manner that impacts safety and traffic flow negatively when distracted.
1 Wellcome Department of Imaging Neuroscience and 2 Institute of Cognitive Neuroscience, University College London, London WC1N 3BG, United Kingdom
Submitted 17 February 2004;
accepted in final form ...23 April 2004
The distributed model of face processing proposes an anatomical dissociation between brain regions that encode invariant aspects of faces, such as identity, and those that encode changeable aspects of faces, such as expression. We tested for a neuroanatomical dissociation for identity and expression in face perception using a functional MRI (fMRI) adaptation paradigm. Repeating identity across face pairs led to reduced fMRI signal in fusiform cortex and posterior superior temporal sulcus (STS), whereas repeating emotional expression across pairs led to reduced signal in a more anterior region of STS. These results provide neuroanatomical evidence for the distributed model of face processing and highlight a dissociation within right STS between a caudal segment coding identity and a more rostral region coding emotional expression.
Address for reprint requests and other correspondence: J. Winston, Wellcome Department of Imaging Neuroscience, 12 Queen Square, London WC1N 3BG, UK (E-mail: j.winston{at}fil.ion.ucl.ac.uk ).
Objective
To evaluate rheumatoid arthritis (RA) and mortality risk among women followed prospectively in the Nurses’ Health Study (NHS).
Methods
We analyzed 119,209 women in the NHS who reported no ...connective tissue disease at enrollment in 1976. Comorbidity and lifestyle data were collected through biennial questionnaires. Incident RA cases were validated by medical records review. Cause of death was determined by death certificate and medical records review. Cox regression models estimated hazard ratios (HRs) and 95% confidence intervals (95% CIs) for all‐cause, cardiovascular disease (CVD), cancer, and respiratory disease mortality for women with RA compared to those without RA.
Results
We validated 964 incident RA cases and identified 28,808 deaths during 36 years of prospective follow‐up. Of 307 deaths among women with RA, 80 (26%) were from cancer, 70 (23%) were from CVD, and 44 (14%) were from respiratory causes. Women with RA had increased total mortality (HR 1.40, 95% CI 1.25–1.57) compared to those without RA, independent of mortality risk factors, including smoking. RA was associated with significantly increased respiratory disease mortality (HR 2.06, 95% CI 1.51–2.80) and cardiovascular disease mortality (HR 1.45, 95% CI 1.14–1.83), but not cancer mortality (HR 0.93, 95% CI 0.74–1.15). For women with seropositive RA, respiratory disease mortality was nearly 3‐fold higher than among non‐RA women (HR 2.67, 95% CI 1.89–3.77).
Conclusion
Women with RA had significantly increased mortality compared to those without RA. Respiratory disease and cardiovascular disease mortality were both significantly elevated for women with RA. The nearly 3‐fold increased relative risk of respiratory disease mortality was observed only for those with seropositive RA.
A series of deep stratospheric intrusions in late May 2013 increased the daily maximum 8 h surface ozone (O3) concentrations to more than 70 parts per billion by volume (ppbv) at rural and urban ...surface monitors in California and Nevada. This influx of ozone‐rich lower stratospheric air and entrained Asian pollution persisted for more than 5 days and contributed to exceedances of the 2008 8 h national ambient air quality standard of 75 ppbv on 21 and 25 May in Clark County, NV. Exceedances would also have occurred on 22 and 23 May had the new standard of 70 ppbv been in effect. In this paper, we examine this episode using lidar measurements from a high‐elevation site on Angel Peak, NV, and surface measurements from NOAA, the Clark County, Nevada Department of Air Quality, the Environmental Protection Agency Air Quality System, and the Nevada Rural Ozone Initiative. These measurements, together with analyses from the National Centers for Environmental Prediction/North American Regional Reanalysis; NOAA Geophysical Fluid Dynamics Laboratory AM3 model; NOAA National Environmental Satellite, Data, and Information Service Real‐time Air Quality Modeling System; and FLEXPART models, show that the exceedances followed entrainment of ~20 to 40 ppbv of lower stratospheric ozone mingled with another 0 to 10 ppbv of ozone transported from Asia by the unusually deep convective boundary layers above the Mojave desert. Our analysis suggests that this vigorous mixing can affect both high and low elevations and help explain the springtime ozone maximum in the southwestern U.S.
Plain Language Summary
Ozone (O3) is formed high in the upper atmosphere when ultraviolet (UV) rays from the sun break the bond in molecular oxygen (O2). This so‐called "good" ozone protects plants and animals at the ground from the damaging effects of these UV rays. Ozone is also formed in the lower atmosphere through reactions between nitrogen oxides (NOx) and volatile organic compounds (VOCs) of natural and human origin. This "bad" ozone can damage the sensitive tissues of plants and animals. The U.S. Clean Air Act (CAA) established standards designed to keep the ozone in the air we breathe at healthy levels by regulating NOx and VOC precursors emitted by human activities. The standard is revised periodically as new data on the health effects of ozone become available, and the current standard is close to the normal background levels found in some parts of the U.S. during springtime. This means that the concentrations can sometimes exceed the standard when storms bring "good" ozone from the upper atmosphere down to the ground where it becomes "bad" ozone. We take a look at this process and discuss why it is more likely to happen in the Southwest than in other parts of the U.S.
Key Points
The deep convective boundary layers of the Southwestern U.S. increase entrainment of stratospheric air and transported pollution
Stratospheric intrusions contribute to the springtime surface ozone maximum in the Southwestern U.S.
Stratospheric intrusions can cause exceedances of the National Ambient Air Quality Standard for ozone in the Southwestern U.S.
Amylin, a pancreatic peptide, and amyloid-beta peptides (Aβ), a major component of Alzheimer's disease (AD) brain, share similar β-sheet secondary structures, but it is not known whether pancreatic ...amylin affects amyloid pathogenesis in the AD brain. Using AD mouse models, we investigated the effects of amylin and its clinical analog, pramlintide, on AD pathogenesis. Surprisingly, chronic intraperitoneal (i.p.) injection of AD animals with either amylin or pramlintide reduces the amyloid burden as well as lowers the concentrations of Aβ in the brain. These treatments significantly improve their learning and memory assessed by two behavioral tests, Y maze and Morris water maze. Both amylin and pramlintide treatments increase the concentrations of Aβ1-42 in cerebral spinal fluid (CSF). A single i.p. injection of either peptide also induces a surge of Aβ in the serum, the magnitude of which is proportionate to the amount of Aβ in brain tissue. One intracerebroventricular injection of amylin induces a more significant surge in serum Aβ than one i.p. injection of the peptide. In 330 human plasma samples, a positive association between amylin and Aβ1-42 as well as Aβ1-40 is found only in patients with AD or amnestic mild cognitive impairment. As amylin readily crosses the blood-brain barrier, our study demonstrates that peripheral amylin's action on the central nervous system results in translocation of Aβ from the brain into the CSF and blood that could be an explanation for a positive relationship between amylin and Aβ in blood. As naturally occurring amylin may play a role in regulating Aβ in brain, amylin class peptides may provide a new avenue for both treatment and diagnosis of AD.
Prenatal stress is a risk factor for several psychiatric disorders in which inhibitory neuron pathology is implicated. A growing body of research demonstrates that inhibitory circuitry in the brain ...is directly and persistently affected by prenatal stress. This review synthesizes research that explores how this early developmental risk factor impacts inhibitory neurons and how these findings intersect with research on risk factors and inhibitory neuron pathophysiology in schizophrenia, anxiety, autism and Tourette syndrome. The specific impact of prenatal stress on inhibitory neurons, particularly developmental mechanisms, may elucidate further the pathophysiology of these disorders.
ABSTRACT
Rapidly rotating early-type stars with strong magnetic fields frequently show H α emission originating in centrifugal magnetospheres (CMs), circumstellar structures in which centrifugal ...support due to magnetically enforced corotation of the magnetically confined plasma enables it to accumulate to high densities. It is not currently known whether the CM plasma escapes via centrifugal breakout (CB), or by an unidentified leakage mechanism. We have conducted the first comprehensive examination of the H α emission properties of all stars currently known to display CM-pattern emission. We find that the onset of emission is dependent primarily on the area of the CM, which can be predicted simply by the value BK of the magnetic field at the Kepler corotation radius RK. Emission strength is strongly sensitive to both CM area and BK. Emission onset and strength are not dependent on effective temperature, luminosity, or mass-loss rate. These results all favour a CB scenario; however, the lack of intrinsic variability in any CM diagnostics indicates that CB must be an essentially continuous process, i.e. it effectively acts as a leakage mechanism. We also show that the emission profile shapes are approximately scale-invariant, i.e. they are broadly similar across a wide range of emission strengths and stellar parameters. While the radius of maximum emission correlates closely as expected to RK, it is always larger, contradicting models that predict that emission should peak at RK.
Global ship-based programs, with highly accurate, full water column physical and biogeochemical observations repeated decadally since the 1970s, provide a crucial resource for documenting ocean ...change. The ocean, a central component of Earth's climate system, is taking up most of Earth's excess anthropogenic heat, with about 19% of this excess in the abyssal ocean beneath 2,000 m, dominated by Southern Ocean warming. The ocean also has taken up about 27% of anthropogenic carbon, resulting in acidification of the upper ocean. Increased stratification has resulted in a decline in oxygen and increase in nutrients in the Northern Hemisphere thermocline and an expansion of tropical oxygen minimum zones. Southern Hemisphere thermocline oxygen increased in the 2000s owing to stronger wind forcing
and ventilation. The most recent decade of global hydrography has mapped dissolved organic carbon, a large, bioactive reservoir, for the first time and quantified its contribution to export production (∼20%) and deep-ocean oxygen utilization. Ship-based measurements also show that vertical diffusivity increases from a minimum in the thermocline to a maximum within the bottom 1,500 m, shifting our physical paradigm of the ocean's overturning circulation.
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