6,164 research outputs found
Sulphur dioxide sensitivity in South African asthmatic children
Sulphur dioxide (SO2) is a well-known precipitant of asthmatic attacks. Many foodstuffs are preserved with SO2 and other sulphites. In this study 37 asthmatic children attending the Allergy Clinic at the Red Cross Children's Hospital were challenged with SO2 in apple juice in a dose similar to that commonly ingested in soft-drinks containing this preservative. The responses of these children were compared with the responses of 22 asthmatics challenged with apple juice alone.Sixteen out of 37 children (43,2%) challenged with SO2 reacted with a fall in forced expiratory volume in 1 second (FEV1) of more than 10% compared with none of the 22 control asthmatic children challenged with apple juice alone (P = 0,0016). Girls were found to be more sensitive than boys. A 20% or more fall in FEV1 occurred in 8 (21,6%) of the children challenged with SO2 compared with none in the control group (P = 0,039). There was an individual variability in the responses of sensitive individuals to the SO2 challenge. Reactions occurred in spite of maintenance medication and occurred within 5 - 30 minutes of challenge. Since sulphite sensitivity is common in asthmatic children, ingestion of sulphites should be avoided
Talking about Hillsborough: ‘panic’ as discourse in survivors' accounts of the 1989 football stadium disaster
Popular representations of crowd behaviour in disasters are often characterised by irrationalist discourses, in particular ‘mass panic’ despite their rejection by current scientific research. This paper reports an analysis of four survivors' accounts of the 1989 Hillsborough disaster to investigate if and how they used the term ‘panic’. Reference to ‘panic’ occurred frequently, but more detailed analysis found that their accounts did not match the classic criteria for ‘mass panic’ (e.g. uncontrolled emotion and selfish behaviour). Indeed, participants referred to ‘orderly’ behaviour, and cooperation, even when they said the threat of death was present. ‘Panic’ was therefore being used as a description of events that was not consistent. A discourse analysis of usage suggests that participants used ‘panic’ not only to convey feelings of fear and distress but also to apportion culpability towards the actions of the police who they considered responsible for the tragedy (as indeed recent independent research has confirmed). It is concluded that the term ‘panic’ is so deeply embedded in popular discourse that people may use it even when they have reason to reject its irrationalist implications. Alternative discourses that emphasise collective resilience in disasters are suggested
A Detailed Investigation into Low-Level Feature Detection in Spectrogram Images
Being the first stage of analysis within an image, low-level feature detection is a crucial step in the image analysis process and, as such, deserves suitable attention. This paper presents a systematic investigation into low-level feature detection in spectrogram images. The result of which is the identification of frequency tracks. Analysis of the literature identifies different strategies for accomplishing low-level feature detection. Nevertheless, the advantages and disadvantages of each are not explicitly investigated. Three model-based detection strategies are outlined, each extracting an increasing amount of information from the spectrogram, and, through ROC analysis, it is shown that at increasing levels of extraction the detection rates increase. Nevertheless, further investigation suggests that model-based detection has a limitation—it is not computationally feasible to fully evaluate the model of even a simple sinusoidal track. Therefore, alternative approaches, such as dimensionality reduction, are investigated to reduce the complex search space. It is shown that, if carefully selected, these techniques can approach the detection rates of model-based strategies that perform the same level of information extraction. The implementations used to derive the results presented within this paper are available online from http://stdetect.googlecode.com
JME 4110 Mechanical Engineering Design Project - Combination Machining Tool
Design and build a portable sized tool for machining relatively small parts out of metal. Ideally, a student could keep it in their dorm and bring it to an appropriate work space when he/she is ready to use it
Subsurface morphology and scaling of lunar impact basins
Impact bombardment during the first billion years after the formation of the Moon produced at least several tens of basins. The Gravity Recovery and Interior Laboratory (GRAIL) mission mapped the gravity field of these impact structures at significantly higher spatial resolution than previous missions, allowing for detailed subsurface and morphological analyses to be made across the entire globe. GRAIL-derived crustal thickness maps were used to define the regions of crustal thinning observed in centers of lunar impact basins, which represents a less unambiguous measure of a basin size than those based on topographic features. The formation of lunar impact basins was modeled numerically by using the iSALE-2D hydrocode, with a large range of impact and target conditions typical for the first billion years of lunar evolution. In the investigated range of impactor and target conditions, the target temperature had the dominant effect on the basin subsurface morphology. Model results were also used to update current impact scaling relationships applicable to the lunar setting (based on assumed target temperature). Our new temperature-dependent impact-scaling relationships provide estimates of impact conditions and transient crater diameters for the majority of impact basins mapped by GRAIL. As the formation of lunar impact basins is associated with the first ~700 Myr of the solar system evolution when the impact flux was considerably larger than the present day, our revised impact scaling relationships can aid further analyses and understanding of the extent of impact bombardment on the Moon and terrestrial planets in the early solar system
Reward Shaping for User Satisfaction in a REINFORCE Recommender
How might we design Reinforcement Learning (RL)-based recommenders that
encourage aligning user trajectories with the underlying user satisfaction?
Three research questions are key: (1) measuring user satisfaction, (2)
combatting sparsity of satisfaction signals, and (3) adapting the training of
the recommender agent to maximize satisfaction. For measurement, it has been
found that surveys explicitly asking users to rate their experience with
consumed items can provide valuable orthogonal information to the
engagement/interaction data, acting as a proxy to the underlying user
satisfaction. For sparsity, i.e, only being able to observe how satisfied users
are with a tiny fraction of user-item interactions, imputation models can be
useful in predicting satisfaction level for all items users have consumed. For
learning satisfying recommender policies, we postulate that reward shaping in
RL recommender agents is powerful for driving satisfying user experiences.
Putting everything together, we propose to jointly learn a policy network and a
satisfaction imputation network: The role of the imputation network is to learn
which actions are satisfying to the user; while the policy network, built on
top of REINFORCE, decides which items to recommend, with the reward utilizing
the imputed satisfaction. We use both offline analysis and live experiments in
an industrial large-scale recommendation platform to demonstrate the promise of
our approach for satisfying user experiences.Comment: Accepted in Reinforcement Learning for Real Life (RL4RealLife)
Workshop in the 38th International Conference on Machine Learning, 202
Sensory profile of portuguese white wines using long-term memory: a novel nationwide approach
White wine sensory profiling of all 12 Protected Geographical Indications (PGIs)
of mainland Portugal was achieved through completion of extended sensory
questionnaires by 20 professional wine experts. No samples were assessed; the
experiment was based on memory alone. Three macro-zonings were found and
typicality differences were statistically validated and sensory described. PGI
MINHO was found the most typical of all PGIs, with several extreme rates on
Color, Aroma and Taste. SOUTHERN cluster of the four meridional PGIs
presented several extreme, therefore typical, sensory assessments, mostly opposite
to the profile of PGI Minho. Color tonality, alcohol and acidity were mutually
related and respective variations were correlated with published findings and
expressed as key factors for regional macro-zoning differentiation. Moreover, with
the proposed methodology it was possible to achieve a novel nationwide sensory
characterization of PGIs, overcoming ongoing macroscaling and sample
representativeness limitations and envisaging new nation-sized sensory studiesinfo:eu-repo/semantics/publishedVersio
Colorectal cancer linkage on chromosomes 4q21, 8q13, 12q24, and 15q22
A substantial proportion of familial colorectal cancer (CRC) is not a consequence of known susceptibility loci, such as mismatch repair (MMR) genes, supporting the existence of additional loci. To identify novel CRC loci, we conducted a genome-wide linkage scan in 356 white families with no evidence of defective MMR (i.e., no loss of tumor expression of MMR proteins, no microsatellite instability (MSI)-high tumors, or no evidence of linkage to MMR genes). Families were ascertained via the Colon Cancer Family Registry multi-site NCI-supported consortium (Colon CFR), the City of Hope Comprehensive Cancer Center, and Memorial University of Newfoundland. A total of 1,612 individuals (average 5.0 per family including 2.2 affected) were genotyped using genome-wide single nucleotide polymorphism linkage arrays; parametric and non-parametric linkage analysis used MERLIN in a priori-defined family groups. Five lod scores greater than 3.0 were observed assuming heterogeneity. The greatest were among families with mean age of diagnosis less than 50 years at 4q21.1 (dominant HLOD = 4.51, α = 0.84, 145.40 cM, rs10518142) and among all families at 12q24.32 (dominant HLOD = 3.60, α = 0.48, 285.15 cM, rs952093). Among families with four or more affected individuals and among clinic-based families, a common peak was observed at 15q22.31 (101.40 cM, rs1477798; dominant HLOD = 3.07, α = 0.29; dominant HLOD = 3.03, α = 0.32, respectively). Analysis of families with only two affected individuals yielded a peak at 8q13.2 (recessive HLOD = 3.02, α = 0.51, 132.52 cM, rs1319036). These previously unreported linkage peaks demonstrate the continued utility of family-based data in complex traits and suggest that new CRC risk alleles remain to be elucidated. © 2012 Cicek et al
Human Papillomavirus Risk Perceptions Among Young Adult Sexual Minority Cisgender Women and Nonbinary Individuals Assigned Female at Birth
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148405/1/psrh12087_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148405/2/psrh12087.pd
Near Infrared polarimetry of a sample of YSOs
Our goal is to study the physical properties of the circumstellar environment
of young stellar objetcs (YSOs). In particular, the determination of the
scattering mechanism can help to constrain the optical depth of the disk and/or
envelope in the near infrared. We used the IAGPOL imaging polarimeter along
with the CamIV infrared camera at the LNA observatory to obtain near infrared
polarimetry measurements at the H band of a sample of optically visible YSOs,
namely, eleven T Tauri stars and eight Herbig Ae/Be stars. An independent
determination of the disk (or jet) orientation was obtained for twelve objects
from the literature. The circumstellar optical depth could be then estimated
comparing the integrated polarization position angle (PA) with the direction of
the major axis of the disk projected in the plane of the sky. In general,
optically thin disks have polarization PA perpendicular to the disk plane. In
contrast, optically thick disks produce polarization PA parallel to the disks.
Among the T Tauri stars, three are consistent with optically thin disks (AS
353A, RY Tau and UY Aur) and five with optically thick disks (V536 Aql, DG Tau,
DO Tau, HL Tau and LkHalpha 358). Among the Herbig Ae/Be stars, two stars show
evidence of optically thin disk (Hen 3-1191 and VV Ser) and two of optically
thick disks (PDS 453 and MWC 297). Our results seem consistent with the fact
that optically thick disks at near infrared bands are associated more likely
with younger YSOs. Marginal evidence of polarization reversal is found in RY
Tau, RY Ori, WW Vul, and UY Aur. On the first three cases this feature can be
associated to the UXOR phenomenon. Correlations with the IRAS colours and the
spectral index yielded evidence of an evolutionary segregation with the disks
tend to be optically thin when they are older.Comment: 15 pages, 15 figures, accepted in Astronomy and Astrophysic
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