43 research outputs found
The Similarity Hypothesis in General Relativity
Self-similar models are important in general relativity and other fundamental
theories. In this paper we shall discuss the ``similarity hypothesis'', which
asserts that under a variety of physical circumstances solutions of these
theories will naturally evolve to a self-similar form. We will find there is
good evidence for this in the context of both spatially homogenous and
inhomogeneous cosmological models, although in some cases the self-similar
model is only an intermediate attractor. There are also a wide variety of
situations, including critical pheneomena, in which spherically symmetric
models tend towards self-similarity. However, this does not happen in all cases
and it is it is important to understand the prerequisites for the conjecture.Comment: to be submitted to Gen. Rel. Gra
Rare variants with large effects provide functional insights into the pathology of migraine subtypes, with and without aura
Publisher Copyright: © 2023, The Author(s).Migraine is a complex neurovascular disease with a range of severity and symptoms, yet mostly studied as one phenotype in genome-wide association studies (GWAS). Here we combine large GWAS datasets from six European populations to study the main migraine subtypes, migraine with aura (MA) and migraine without aura (MO). We identified four new MA-associated variants (in PRRT2, PALMD, ABO and LRRK2) and classified 13 MO-associated variants. Rare variants with large effects highlight three genes. A rare frameshift variant in brain-expressed PRRT2 confers large risk of MA and epilepsy, but not MO. A burden test of rare loss-of-function variants in SCN11A, encoding a neuron-expressed sodium channel with a key role in pain sensation, shows strong protection against migraine. Finally, a rare variant with cis-regulatory effects on KCNK5 confers large protection against migraine and brain aneurysms. Our findings offer new insights with therapeutic potential into the complex biology of migraine and its subtypes.Peer reviewe
SciPy 1.0: fundamental algorithms for scientific computing in Python.
SciPy is an open-source scientific computing library for the Python programming language. Since its initial release in 2001, SciPy has become a de facto standard for leveraging scientific algorithms in Python, with over 600 unique code contributors, thousands of dependent packages, over 100,000 dependent repositories and millions of downloads per year. In this work, we provide an overview of the capabilities and development practices of SciPy 1.0 and highlight some recent technical developments
PP149-SUN THE BERGEN NUTRITIONAL STRATEGY: FOUR QUESTIONS PREDICT MORBIDITY, MORTALITY AND EXPENSES IN A UNIVERSITY HOSPITAL
Combined use of exhaled nitric oxide and airway hyperresponsiveness in characterizing asthma in a large population survey
Exhaled and nasal NO levels in allergic rhinitis: relation to sensitization, pollen season and bronchial hyperresponsiveness
Gender differences in asthma prevalence may depend on how asthma is defined
BACKGROUND: Asthma may be defined either as wheeze within the previous 12 months (current wheeze) doctor-diagnosed asthma (DDA), or current wheeze plus confirmed airway hyperresponsiveness (AHR). AIMS: We wanted to estimate asthma prevalence in randomly selected adolescents based on different criteria for asthma diagnosis, study gender differences in reported asthma-like symptoms vs DDA, and relate our findings to measurements of AHR, levels of exhaled nitric oxide (ENO) and total IgE. METHODS: As part of the health survey of North-Trondelag (HUNT), 8571 adolescents aged 13-19 years were investigated with an interview on allergic and respiratory symptoms (phase I study). Of these, 401 subjects who reported wheeze within the previous 12 months (current wheeze) and 213 non-symptomatic controls were randomly selected and investigated with allergy screening, methacholine bronchoprovocation test and measurements of ENO (phase II study). RESULTS: In the phase I study prevalence of current wheeze was 26% (30% in girls and 23% in boys, P < 0.01). Prevalence of DDA was 10.8% (10.5% in girls and 11% in boys). Among subjects with current wheeze, the likelihood of having DDA was reduced in girls compared to boys, odds ratio (95% CI) 0.82 (0.68-0.98) which was partly explained by a longer history of wheeze among boys. In the phase II study, although more girls than boys with current wheeze had AHR (62% versus 50%, P < 0.02) more boys than girls reported DDA (44% vs. 32%, P < 0.02). Of the objective parameters, increased levels of ENO most strongly increased the risk of having DDA. CONCLUSIONS: When asthma is defined as DDA, there is a risk of underestimating the prevalence of asthma, especially among girls