235 research outputs found
Predictors of airway hyperreactivity in house dust mite allergic patients
Introduction: Airway hyperresponsiveness (AHR) is a cardinal feature of asthma. Asthma is a heterogenous disorder which consists of different phenotypes and endotypes. Mechanisms leading to AHR may differ in different asthma subtypes. Allergy to perennial allergens, including house dust mites (HDM) is a major risk factor for asthma development. The aim of this study was to determine predictors of AHR in a well-characterized population of HDM-allergic patients.Material and methods: In a retrospective analysis 843 patients with HDM-allergic rhinitis with/without asthma were evaluated. The following parameters were included in the analysis: serum concentration of total (t)- and Dermatophagoides pteronyssinus (Dp)-specific IgE, fractional exhaled nitric oxide concentration (FeNO), lung function tests, bronchial challenge with histamine, age sex, and body mass index (BMI). Linear regression analysis was used to determine predictors of AHR.Results: In a simple linear regression analysis baseline lung function results expressed as either forced expiratory volume in 1 s (FEV1) or maximal expiratory flow at 50% of the forced vital capacity (MEF50), FeNO, tIgE, DpIgE, age and BMI affected AHR. A multiple regression analysis demonstrated that in the whole group of HDM-allergic patients the most important, independent predictors of AHR were MEF50, FeNO and DpIgE.Conclusion: Even in a well-characterized asthma phenotype several processes participate in development of AHR. Major, independent predictors of AHR: lung function parameters, FeNO and DpIgE indicate possible targets for therapeutic intervention in a population of HDM-allergic patients
Electrochemical Model-Based Investigation of Thick LiFePO4 Electrode Design Parameters
The electrification of the powertrain requires enhanced performance of lithium-ion batteries, mainly in terms of energy and power density. They can be improved by optimising the positive electrode, i.e., by changing their size, composition or morphology. Thick electrodes increase the gravimetric energy density but generally have an inefficient performance. This work presents a 2D modelling approach for better understanding the design parameters of a thick LiFePO4 electrode based on the P2D model and discusses it with common literature values. With a superior macrostructure providing a vertical transport channel for lithium ions, a simple approach could be developed to find the best electrode structure in terms of macro- and microstructure for currents up to 4C. The thicker the electrode, the more important are the direct and valid transport paths within the entire porous electrode structure. On a smaller scale, particle size, binder content, porosity and tortuosity were identified as very impactful parameters, and they can all be attributed to the microstructure. Both in modelling and electrode optimisation of lithium-ion batteries, knowledge of the real microstructure is essential as the cross-validation of a cellular and lamellar freeze-casted electrode has shown. A procedure was presented that uses the parametric study when few model parameters are known.DFG, 414044773, Open Access Publizieren 2021 - 2022 / Technische Universität Berli
The Turbulent Warm Ionized Medium: Emission Measure Distribution and MHD Simulations
We present an analysis of the distribution of H-alpha emission measures for
the warm ionized medium (WIM) of the Galaxy using data from the Wisconsin
H-Alpha Mapper (WHAM) Northern Sky Survey. Our sample is restricted to Galactic
latitudes |b| > 10. We removed sightlines intersecting nineteen high-latititude
classical H II regions, leaving only sightlines that sample the diffuse WIM.
The distribution of EM sin |b| for the full sample is poorly characterized by a
single normal distribution, but is extraordinarily well fit by a lognormal
distribution, with = 0.146 +/- 0.001 and standard deviation
0.190 +/- 0.001. drops from 0.260 +/- 0.002 at Galactic
latitude 10<|b|<30 to 0.038 +/- 0.002 at Galactic latitude 60<|b|<90. The
distribution may widen slightly at low Galactic latitude. We compare the
observed EM distribution function to the predictions of three-dimensional
magnetohydrodynamic simulations of isothermal turbulence within a
non-stratified interstellar medium. We find that the distribution of EM sin |b|
is well described by models of mildy supersonic turbulence with a sonic Mach
number of ~1.4-2.4. The distribution is weakly sensitive to the magnetic field
strength. The model also successfully predicts the distribution of dispersion
measures of pulsars and H-alpha line profiles. In the best fitting model, the
turbulent WIM occupies a vertical path length of 400-500 pc within the 1.0-1.8
kpc scale height of the layer. The WIM gas has a lognormal distribution of
densities with a most probable electron density n_{pk} = 0.03 cm^{-3}. We also
discuss the implications of these results for interpreting the filling factor,
the power requirement, and the magnetic field of the WIM.Comment: 16 pages, 13 figures, ApJ in press. Replacement reflects version
accepted for publicatio
What kind of heart rhythm is this?
Pacjent w wieku 81 lat ze złożoną wadą serca pod postacią ciężkiej stenozy zastawki aortalnej i niedomykalności zastawki mitralnej (kwalifikowany do przezskórnej implantacja zastawki aortalnej), z przewlekłą niewydolnością serca (II klasa wg New York Heart Association [NYHA]), z wywiadem napadowego migotania przedsionków, cukrzycą typu 2, nadciśnieniem tętniczym i tętniakiem aorty brzusznej został przyjęty do Kliniki Kardiologii i Chorób Wewnętrznych WIM z powodu zaostrzenia niewydolności serca (III/IV klasa wg NYHA). Wcześniej był 2-krotnie hospitalizowany — w elektrokardiogramie (EKG) opisywano tachykardię zatokową. W EKG z kolejnej hospitalizacji opisano częstoskurcz przedsionkowy z blokiem 2:1, z miarową czynnością komór 100/min. Opis przypadku obrazuje trudności w różnicowaniu częstoskurczu przedsionkowego i tachykardii zatokowej.A 81-year-old man with severe aortic stenosis (qualified for transcatheter aortic valve implantation), mitral insufficiency, chronic heart failure (New York Heart Association [NYHA] II), paroxysmal atrial fibrillation, diabetes mellitus type 2, hypertension, abdominal aortic aneurysm was admitted to the Clinic because of heart failure exacerbation (NYHA III/IV). In the past patient was hospitalized twice — rhythm in electrocardiogram (ECG) was described as sinus tachycardia. During next hospitalization on ECG there was atrial tachycardia with 2:1 block and regular ventricular rate 100/min. This case report demonstrates difficulty in distinguishing sinus tachycardia and atrial tachycardia
Wszczepiono CRT-P i co dalej…
One of the main reason of hospitalization are arrhythmias and conduction disorders, exceptionally rarely they may have a genetic basis. Muscular dystrophy Emery-Dreifuss is a genetic disease in which the image of muscular atrophy and abnormal heart rhythm and conduction disturbances, which often require immediate intervention. Characteristic of patients with muscular dystrophy Emery-Dreifuss is the presence of the absence of the electrical activity of the atrial (atrial standstill, atrial paralysis), which is caused by atrial muscle fibrosis, as well as the conduction system. The paper presents a patient with suspected Emery’ego-Dreifuss muscular dystrophy in which besides conduction disturbances requiring pacemaker implantation occurred as complex ventricular arrhythmias, which required the extension of the CRT-P to CRT-D.Jednym z głównych powodów hospitalizacji są zaburzenia rytmu i przewodzenia, których podłoże wyjątkowo rzadko bywa genetyczne. Dystrofia mięśniowa Emery’ego-Dreifussa jest chorobą uwarunkowaną genetycznie, w obraz której wpisują się zaniki mięśniowe oraz zaburzenia rytmu serca i zaburzenia przewodzenia, które często wymagają natychmiastowej interwencji. Charakterystyczny dla pacjentów z tą dystrofią jest brak czynności elektrycznej przedsionków (atrial standstill, atrial paralysis) spowodowany włóknieniem mięśniówki przedsionków, a także układu bodźco-przewodzącego. W pracy przedstawiono chorego z podejrzeniem dystrofii Emery’ego-Dreifussa, u którego poza zaburzeniami przewodzenia wymagającymi wszczepienia układu stymulującego serce wystąpiły także złożone komorowe zaburzenia rytmu, co wymagało rozszerzenia układu CRT-P do CRT-D
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