Search results for "breath"
showing 10 items of 528 documents
Mapping cyclic stretch in the postpneumonectomy murine lung
2013
In many mammalian species, the removal of one lung [pneumonectomy (PNX)] is associated with the compensatory growth of the remaining lung. To investigate the hypothesis that parenchymal deformation may trigger lung regeneration, we used respiratory-gated micro-computed tomography scanning to create three-dimensional finite-element geometric models of the murine cardiac lobe with cyclic breathing. Models were constructed of respiratory-gated micro-computed tomography scans pre-PNX and 24 h post-PNX. The computational models demonstrated that the maximum stretch ratio map was patchy and heterogeneous, particularly in subpleural, juxta-diaphragmatic, and cephalad regions of the lobe. In these…
Recurrent aphthous stomatitis and Helicobacter pylori
2016
Background Recurrent aphthous stomatitis (RAS) is a recurrent painful ulcerative disorder that commonly affects the oral mucosa. Local and systemic factors such as trauma, food sensitivity, nutritional deficiencies, systemic conditions, immunological disorders and genetic polymorphisms are associated with the development of the disease. Helicobacter pylori (H. pylori) is a gram-negative, microaerophile bacteria, that colonizes the gastric mucosa and it was previously suggested to be involved in RAS development. In the present paper we reviewed all previous studies that investigated the association between RAS and H. pylori. Material and Methods A search in Pubmed (MEDLINE) databases was mad…
Usefulness of complementary test in the study of patients with chronic abdominal pain.
2021
Introduction: Chronic abdominal pain (CAP) in children is a symptom that frequently leads to a visit to the paediatrician, which affects family life and occasionally requires the need to perform diagnostic studies (DS). The objective was to carry out a qualitative, quantitative, and economic analysis on the tests requested. Material and methods: An observational, prospective and multicentre study was conducted that included children between 4–15 years old affected by CAP. The difference between organic and functional disorders was taken into account. The following variables were collected: history, warning signs and symptoms, DS, and the cost of these. Results: The study included 235 childr…
It Takes a Mouth to Eat and a Nose to Breathe: Abnormal Oral Respiration Affects Neonates' Oral Competence and Systemic Adaptation.
2012
Review Article; International audience; Mammalian, including human, neonates are considered to be obligate nose breathers. When constrained to breathe through their mouth in response to obstructed or closed nasal passages, the effects are pervasive and profound, and sometimes last into adulthood. The present paper briefly surveys neonates' and infants' responses to this atypical mobilisation of the mouth for breathing and focuses on comparisons between human newborns and infants and the neonatal rat model. We present the effects of forced oral breathing on neonatal rats induced by experimental nasal obstruction. We assessed the multilevel consequences on physiological, structural, and behav…
Paediatric Sleep Questionnaire for Obstructive Sleep Apnoea Syndrome Screening: Is Sleep Quality Worthy of Note?
2021
Obstructive sleep apnoea syndrome (OSAS) is the most severe condition on the spectrum of sleep-related breathing disorders (SRBDs). The Paediatric Sleep Questionnaire (PSQ) is one of the most used and validated screening tools, but it lacks the comprehensive assessment of some determinants of OSAS, specifically anamnestic assessment and sleep quality. This study aims to assess the accuracy of some specific items added to the original PSQ, particularly related to the patient’s anamnestic history and to the quality of sleep, for the screening of OSAS in a paediatric population living in Sicily (Italy). Fifteen specific items, divided into “anamnestic” and “related to sleep quality” were added…
Detection of cancer through exhaled breath: a systematic review
2015
// Agne Krilaviciute 1 , Jonathan Alexander Heiss 1 , Marcis Leja 2 , Juozas Kupcinskas 3 , Hossam Haick 4 and Hermann Brenner 1,5,6 1 Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany 2 Faculty of Medicine, University of Latvia, Digestive Diseases Center GASTRO, and Riga East University Hospital, Riga, Latvia 3 Department of Gastroenterology, Lithuanian University of Health Sciences, Kaunas, Lithuania 4 Department of Chemical Engineering and Russell Berrie Nanotechnology Institute, Technion – Israel Institute of Technology, Haifa, Israel 5 Division of Preventive Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany…
Breather dynamics in a stochastic sine-Gordon equation: evidence of noise-enhanced stability
2023
The dynamics of sine-Gordon breathers is studied in the presence of dissipative and stochastic perturbations. Taking a stationary breather with a random phase value as the initial state, the performed simulations demonstrate that a spatially-homogeneous noisy source can make the oscillatory excitation more stable, i.e., it enables the latter to last significantly longer than it would in a noise-free scenario. Both the frequency domain and the localization of energy are examined to document the effectiveness of the noise-enhanced stability phenomenon, which emerges as a nonmonotonic behavior of an average characteristic time for the breather as a function of the noise intensity. The influenc…
Control of Space-Time Trajectories of Noise-Driven Optical Extreme Events in Metamaterial Waveguides
2019
Metamaterials offer the potential to precisely manipulate electromagnetic wave propagation in ways that cannot be achieved with materials found in nature. The formation and propagation of optical spatial solitons in metamaterials has been already investigated [1]. Here we report the theoretical and numerical investigations on temporal-spectral dynamics of nonlinear extreme events arising from the initial noise-perturbed plane wave in metamaterial waveguides. A typical waveguide structure used here is a planar structure with a metamaterial core and a part of the structure, in the form of the substrate, is replaced with a magnetooptic material. We assume that the core material is isotropic an…
Superregular Breathers in Optics and Hydrodynamics: Omnipresent Modulation Instability beyond Simple Periodicity
2015
Since the 1960s, the Benjamin-Feir (or modulation) instability (MI) has been considered as the self-modulation of the continuous “envelope waves” with respect to small periodic perturbations that precedes the emergence of highly localized wave structures. Nowadays, the universal nature of MI is established through numerous observations in physics. However, even now, 50 years later, more practical but complex forms of this old physical phenomenon at the frontier of nonlinear wave theory have still not been revealed (i.e., when perturbations beyond simple harmonic are involved). Here, we report the evidence of the broadest class of creation and annihilation dynamics of MI, also called superre…
Hydrodynamics of periodic breathers
2014
We report the first experimental observation of periodic breathers in water waves. One of them is Kuznetsov–Ma soliton and another one is Akhmediev breather. Each of them is a localized solution of the nonlinear Schrödinger equation (NLS) on a constant background. The difference is in localization which is either in time or in space. The experiments conducted in a water wave flume show results that are in good agreement with the NLS theory. Basic features of the breathers that include the maximal amplitudes and spectra are consistent with the theoretical predictions.