1,007 research outputs found
Atomic emission in the ultraviolet nightglow
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95222/1/grl4575.pd
CHEM2D-OPP: A new linearized gas-phase ozone photochemistry parameterization for high-altitude NWP and climate models
The new CHEM2D-Ozone Photochemistry Parameterization (CHEM2D-OPP) for high-altitude numerical weather prediction (NWP) systems and climate models specifies the net ozone photochemical tendency and its sensitivity to changes in ozone mixing ratio, temperature and overhead ozone column based on calculations from the CHEM2D interactive middle atmospheric photochemical transport model. We evaluate CHEM2D-OPP performance using both short-term (6-day) and long-term (1-year) stratospheric ozone simulations with the prototype high-altitude NOGAPS-ALPHA forecast model. An inter-comparison of NOGAPS-ALPHA 6-day ozone hindcasts for 7 February 2005 with ozone photochemistry parameterizations currently used in operational NWP systems shows that CHEM2D-OPP yields the best overall agreement with both individual Aura Microwave Limb Sounder ozone profile measurements and independent hemispheric (10°–90° N) ozone analysis fields. A 1-year free-running NOGAPS-ALPHA simulation using CHEM2D-OPP produces a realistic seasonal cycle in zonal mean ozone throughout the stratosphere. We find that the combination of a model cold temperature bias at high latitudes in winter and a warm bias in the CHEM2D-OPP temperature climatology can degrade the performance of the linearized ozone photochemistry parameterization over seasonal time scales despite the fact that the parameterized temperature dependence is weak in these regions
The Compositional Nature of Verb and Argument Representations in the Human Brain
How does the human brain represent simple compositions of objects, actors,and
actions? We had subjects view action sequence videos during neuroimaging (fMRI)
sessions and identified lexical descriptions of those videos by decoding (SVM)
the brain representations based only on their fMRI activation patterns. As a
precursor to this result, we had demonstrated that we could reliably and with
high probability decode action labels corresponding to one of six action videos
(dig, walk, etc.), again while subjects viewed the action sequence during
scanning (fMRI). This result was replicated at two different brain imaging
sites with common protocols but different subjects, showing common brain areas,
including areas known for episodic memory (PHG, MTL, high level visual
pathways, etc.,i.e. the 'what' and 'where' systems, and TPJ, i.e. 'theory of
mind'). Given these results, we were also able to successfully show a key
aspect of language compositionality based on simultaneous decoding of object
class and actor identity. Finally, combining these novel steps in 'brain
reading' allowed us to accurately estimate brain representations supporting
compositional decoding of a complex event composed of an actor, a verb, a
direction, and an object.Comment: 11 pages, 6 figure
Colorectal cancer Outcomes in people with Severe Mental Illness Cohort (COSMIC): A protocol for an Australian retrospective cohort using linked administrative data
Introduction: Colorectal cancer (CRC) mortality is significantly higher in those with severe mental illness (SMI) compared with the general population, despite similar incidence rates, suggesting that barriers to optimal screening and cancer care may contribute to disparities in CRC mortality in those with SMI. This study aims to compare participation in Australia's National Bowel Cancer Screening Programme (NBCSP) in those with SMI and those in the general population. We will also investigate treatment pathways after diagnosis to determine whether treatment variations could explain differences in CRC mortality.
Methods and analysis: We will undertake a retrospective cohort study of Australians using linked administrative data to assess differences in screening and cancer care between those with and without SMI, aged 50-74 years on or after 1 January 2006. People with SMI will be defined using antipsychotic medication prescription data. The comparison group will be people enrolled in Medicare (Australia's universal healthcare system) who have not been prescribed antipsychotic medication. Data on outcomes (NBCSP participation, follow-up colonoscopy, CRC incidence and CRC-cause and all-cause mortality) and confounders will be obtained from national-based and state-based administrative health datasets. All people in New South Wales, aged 50-74 with a new diagnosis of CRC on or after 1 January 2006, will be ascertained to examine stage at diagnosis and cancer treatment in those with and without SMI. Poisson regression will be used to calculate incidence rates and rate ratios for each outcome.
Ethics and dissemination: Ethics approval has been obtained from the University of Queensland Human Research Ethics Committee, the Australian Institute of Health and Welfare Ethics Committee and data custodians from every Australian State/Territory. Findings will be disseminated via publications in peer-reviewed journals and presented at appropriate conferences. Trial registration number ACTRN12620000781943
Assimilation of stratospheric and mesospheric temperatures from MLS and SABER into a global NWP model
International audienceThe forecast model and three-dimensional variational data assimilation components of the Navy Operational Global Atmospheric Prediction System (NOGAPS) have each been extended into the upper stratosphere and mesosphere to form an Advanced Level Physics High Altitude (ALPHA) version of NOGAPS extending to ~100 km. This NOGAPS-ALPHA NWP prototype is used to assimilate stratospheric and mesospheric temperature data from the Microwave Limb Sounder (MLS) and the Sounding of the Atmosphere using Broadband Radiometry (SABER) instruments. A 60-day analysis period in January and February, 2006, was chosen that includes a well documented stratospheric sudden warming. SABER temperatures indicate that the SSW caused the polar winter stratopause at ~40 km to disappear, then reform at ~80 km altitude and slowly descend during February. The NOGAPS-ALPHA analysis reproduces this observed stratospheric and mesospheric temperature structure, as well as realistic evolution of zonal winds, residual velocities, and Eliassen-Palm fluxes that aid interpretation of the vertically deep circulation and eddy flux anomalies that developed in response to this wave-breaking event. The observation minus forecast (O-F) standard deviations for MLS and SABER are ~2 K in the mid-stratosphere and increase monotonically to about 6 K in the upper mesosphere. Increasing O-F standard deviations in the mesosphere are expected due to increasing instrument error and increasing geophysical variance at small spatial scales in the forecast model. In the mid/high latitude winter regions, 10-day forecast skill is improved throughout the upper stratosphere and mesosphere when the model is initialized using the high-altitude analysis based on assimilation of both SABER and MLS data
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Persistence of upper stratospheric wintertime tracer variability into the Arctic spring and summer
Using data from the Aeronomy of Ice in the Mesosphere (AIM) and Aura
satellites, we have categorized the interannual variability of winter- and
springtime upper stratospheric methane (CH4). We further show the effects
of this variability on the chemistry of the upper stratosphere throughout the
following summer. Years with strong wintertime mesospheric descent followed
by dynamically quiet springs, such as 2009, lead to the lowest summertime
CH4. Years with relatively weak wintertime descent, but strong springtime
planetary wave activity, such as 2011, have the highest summertime CH4. By
sampling the Aura Microwave Limb Sounder (MLS) according to the occultation
pattern of the AIM Solar Occultation for Ice Experiment (SOFIE), we show that
summertime upper stratospheric chlorine monoxide (ClO) almost perfectly
anticorrelates with the CH4. This is consistent with the reaction of
atomic chlorine with CH4 to form the reservoir species, hydrochloric acid
(HCl). The summertime ClO for years with strong, uninterrupted mesospheric
descent is about 50 % greater than in years with strong horizontal
transport and mixing of high CH4 air from lower latitudes. Small, but
persistent effects on ozone are also seen such that between 1 and 2 hPa, ozone
is about 4–5 % higher in summer for the years with the highest CH4
relative to the lowest. This is consistent with the role of the chlorine
catalytic cycle on ozone. These dependencies may offer a means to monitor
dynamical effects on the high-latitude upper stratosphere using summertime
ClO measurements as a proxy. Additionally, these chlorine-controlled ozone decreases,
which are seen to maximize after years with strong uninterrupted wintertime
descent, represent a new mechanism by which mesospheric descent can affect
polar ozone. Finally, given that the effects on ozone appear to persist much
of the rest of the year, the consideration of winter/spring dynamical
variability may also be relevant in studies of ozone trends
Results from two years of ozone data taken with a new, ground-based microwave instrument: An overview
An overview of two years of data obtained with a ground-based microwave instrument is given. Intercomparisons with data obtained by the co-located JPL lidar and by SAGE 2 during near overpasses of the site are discussed, as are comparisons with mesospheric data taken earlier by SME and LIMS. Observations of diurnal variations of mesospheric ozone are shown
The Effect of Attractiveness on Food Sharing Preferences in Human Mating Markets
The current study explored how physical attractiveness affects food sharing by studying payment preferences for hypothetical romantic dinner dates (a hypothetical mating market). We analyzed payment preferences, self-rated attractiveness, and rated attractiveness for hypothetical dates in 416 participants. We hypothesized that (1) men would be more likely to prefer to pay than would women, (2) attractive individuals of both sexes would be less willing to pay, and (3) preferences to enter an exchange would be influenced by the attractiveness of prospective partners such that (3a) men would prefer to pay for attractive women, and (3b) women would prefer to be paid for by attractive men. All hypotheses were supported by our results. Individuals with higher self-rated attractiveness were more likely to prefer that their date would pay for the meal, and we found clear sex differences in how the attractiveness of potential dates affected payment preferences. Male participants preferred to pay for dates that had higher facial attractiveness, while female participants preferred that attractive men would pay. Individuals show condition dependent financial preferences consistent with the provisioning hypothesis in this mating market that are adaptive to evaluations of their own quality and that of prospective partners
Inductive learning spatial attention
This paper investigates the automatic induction of spatial attention
from the visual observation of objects manipulated
on a table top. In this work, space is represented in terms of
a novel observer-object relative reference system, named Local
Cardinal System, defined upon the local neighbourhood
of objects on the table. We present results of applying the
proposed methodology on five distinct scenarios involving
the construction of spatial patterns of coloured blocks
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