5,281 research outputs found
Dynamic low-level context for the detection of mild traumatic brain injury.
Mild traumatic brain injury (mTBI) appears as low contrast lesions in magnetic resonance (MR) imaging. Standard automated detection approaches cannot detect the subtle changes caused by the lesions. The use of context has become integral for the detection of low contrast objects in images. Context is any information that can be used for object detection but is not directly due to the physical appearance of an object in an image. In this paper, new low-level static and dynamic context features are proposed and integrated into a discriminative voxel-level classifier to improve the detection of mTBI lesions. Visual features, including multiple texture measures, are used to give an initial estimate of a lesion. From the initial estimate novel proximity and directional distance, contextual features are calculated and used as features for another classifier. This feature takes advantage of spatial information given by the initial lesion estimate using only the visual features. Dynamic context is captured by the proposed posterior marginal edge distance context feature, which measures the distance from a hard estimate of the lesion at a previous time point. The approach is validated on a temporal mTBI rat model dataset and shown to have improved dice score and convergence compared to other state-of-the-art approaches. Analysis of feature importance and versatility of the approach on other datasets are also provided
Visual and Contextual Modeling for the Detection of Repeated Mild Traumatic Brain Injury.
Currently, there is a lack of computational methods for the evaluation of mild traumatic brain injury (mTBI) from magnetic resonance imaging (MRI). Further, the development of automated analyses has been hindered by the subtle nature of mTBI abnormalities, which appear as low contrast MR regions. This paper proposes an approach that is able to detect mTBI lesions by combining both the high-level context and low-level visual information. The contextual model estimates the progression of the disease using subject information, such as the time since injury and the knowledge about the location of mTBI. The visual model utilizes texture features in MRI along with a probabilistic support vector machine to maximize the discrimination in unimodal MR images. These two models are fused to obtain a final estimate of the locations of the mTBI lesion. The models are tested using a novel rodent model of repeated mTBI dataset. The experimental results demonstrate that the fusion of both contextual and visual textural features outperforms other state-of-the-art approaches. Clinically, our approach has the potential to benefit both clinicians by speeding diagnosis and patients by improving clinical care
LUX likelihood and limits on spin-independent and spin-dependent WIMP couplings with LUXCalc
We present LUXCalc, a new utility for calculating likelihoods and deriving
WIMP-nucleon coupling limits from the recent results of the LUX direct search
dark matter experiment. After a brief review of WIMP-nucleon scattering, we
derive LUX limits on the spin-dependent WIMP-nucleon couplings over a broad
range of WIMP masses, under standard assumptions on the relevant astrophysical
parameters. We find that, under these and other common assumptions, LUX
excludes the entire spin-dependent parameter space consistent with a dark
matter interpretation of DAMA's anomalous signal, the first time a single
experiment has been able to do so. We also revisit the case of spin-independent
couplings, and demonstrate good agreement between our results and the published
LUX results. Finally, we derive constraints on the parameters of an effective
dark matter theory in which a spin-1 mediator interacts with a fermionic WIMP
and Standard Model fermions via axial-vector couplings. A detailed appendix
describes the use of LUXCalc with standard codes to place constraints on
generic dark matter theories.Comment: 16 pages, 6 figures. Software package included as ancillary files.
v2: added references, Baksan limits. v3: clarifications and small
corrections, results unchange
Depression in primary care patients with coronary heart disease: baseline findings from the UPBEAT UK study
BACKGROUND:
An association between depression and coronary heart disease is now accepted but there has been little primary care research on this topic. The UPBEAT-UK studies are centred on a cohort of primary patients with coronary heart disease assessed every six months for up to four years. The aim of this research was to determine the prevalence and associations of depression in this cohort at baseline.
METHOD:
Participants with coronary heart disease were recruited from general practice registers and assessed for cardiac symptoms, depression, quality of life and social problems.
RESULTS:
803 people participated. 42% had a documented history of myocardial infarction, 54% a diagnosis of ischaemic heart disease or angina. 44% still experienced chest pain. 7% had an ICD-10 defined depressive disorder. Factors independently associated with this diagnosis were problems living alone (OR 5.49, 95% CI 2.11-13.30), problems carrying out usual activities (OR 3.71, 95% CI 1.93-7.14), experiencing chest pain (OR 3.27, 95% CI 1.58-6.76), other pains or discomfort (OR 3.39, 95% CI 1.42-8.10), younger age (OR 0.95 per year 95% CI 0.92-0.98).
CONCLUSION:
Problems living alone, chest pain and disability are important predictors of depression in this population
Thunder on Water
This collection of fifteen interconnected short stories illustrates the hidden life of women and men who live or have lived in Grenada, Mississippi. The collection focuses on invidual journeys that swell throughout the entire Southern town. Both saintly and profane, Thunder on Water is inspired by works from James Joyce, Flannery O’Connor, Toni Morrison, and many more
Computational analysis reveals increased blood deposition following repeated mild traumatic brain injury.
Mild traumatic brain injury (mTBI) has become an increasing public health concern as subsequent injuries can exacerbate existing neuropathology and result in neurological deficits. This study investigated the temporal development of cortical lesions using magnetic resonance imaging (MRI) to assess two mTBIs delivered to opposite cortical hemispheres. The controlled cortical impact model was used to produce an initial mTBI on the right cortex followed by a second injury induced on the left cortex at 3 (rmTBI 3d) or 7 (rmTBI 7d) days later. Histogram analysis was combined with a novel semi-automated computational approach to perform a voxel-wise examination of extravascular blood and edema volumes within the lesion. Examination of lesion volume 1d post last injury revealed increased tissue abnormalities within rmTBI 7d animals compared to other groups, particularly at the site of the second impact. Histogram analysis of lesion T2 values suggested increased edematous tissue within the rmTBI 3d group and elevated blood deposition in the rm TBI 7d animals. Further quantification of lesion composition for blood and edema containing voxels supported our histogram findings, with increased edema at the site of second impact in rmTBI 3d animals and elevated blood deposition in the rmTBI 7d group at the site of the first injury. Histological measurements revealed spatial overlap of regions containing blood deposition and microglial activation within the cortices of all animals. In conclusion, our findings suggest that there is a window of tissue vulnerability where a second distant mTBI, induced 7d after an initial injury, exacerbates tissue abnormalities consistent with hemorrhagic progression
PERANCANGAN FILM DOKUMENTER KERIS KERATON SURAKARTA SEBAGAI UPAYA PELESTARIAN WARISAN LELUHUR BUDAYA BANGSA
Keris merupakan salah satu warisan budaya Indonesia yang perlu dilestarikan, dan dikenalkan untuk generasi sekarang. Berdasarkan hasil penelusuran yang dilakukan, ditemukan data bahwa masih adanya masyarakat Surakarta yang beranggapan bahwa keris hanya digunakan sebagai pajangan atau jimat yang masih disangkut-pautkan dengan hal-hal yang berkaitan mistis. Selain itu kurangnya kesadaran masyarakat akan pengetahuan tentang keris dan adanya perbedaan antara keris dalam keraton dan luar keraton Surakarta masih sangat minim di masyarakat. Sehingga perlu adanya media informasi yang mampu memperkenalkan dan memberikan informasi mengenai keris Keraton dan perbedaan keris ini dengan keris luar Keraton melalui media audio visual, salah satunya adalah film dokumenter. Penelitian ini menerapkan metode kualitatif dan strategi linier dalam proses perancangan film dokumenter, sehingga diharapkan mampu menghasilkan media informasi audio visual yang dapat memberikan pengenalan secara detail dan aktual mengenai detail keris dalam keraton dan perbedaanya dengan keris luar keraton kepada masyarakat Surakarta secara khusus dan masyarakat Indonesia secara umum
Gamma rays from muons from WIMPs: Implementation of radiative muon decays for dark matter analyses
Dark matter searches in gamma ray final states often make use of the fact
that photons can be produced from final state muons. Modern Monte Carlo
generators and DM codes include the effects of final state radiation from muons
produced in the dark matter annihilation process itself, but neglect the O(1%)
radiative correction that arises from the subsequent muon decay. After
implementing this correction we demonstrate the effect that it can have on dark
matter phenomenology by considering the case of dark matter annihilation to
four muons via scalar mediator production. We first show that the AMS-02
positron excess can no longer easily be made consistent with this final state
once the Fermi-LAT dwarf limits are calculated with the inclusion of radiative
muon decays, and we next show that the Fermi-LAT galactic centre gamma excess
can be improved with this final state after inclusion of the same effect. We
provide code and tables for the implementation of this effect in the popular
dark matter code micrOMEGAs, providing a solution for any model producing final
state muons.Comment: 11 pages, 7 figures + anc file
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