Numerical studies of tunneling in a nonharmonic time-dependent potential

Azbel' has recently carried out a WKB-analysis of the effects of a nonharmonic time-dependent perturbation embedded in an opaque potential barrier. He suggests the existence of three different transmission regimes: direct tunneling, activation assisted tunneling, and elevator resonant activation. We address the same problem with a numerical technique, and find qualitative agreement with Azbel's picture.Comment: LaTeX document, 15 pages. 4 figures (Fig. 2 comes in 7 pages) in postscript appended to the LaTeX documen

Determinants in early life for asthma development

A reliable screening test in newborns for the subsequent development of bronchial asthma (BA) has not been found yet. This is mainly due to the complexity of BA, being made up by different types and underlying mechanisms. In different studies, a number of risk factors for BA have been identified. These include a positive family history of BA, passive smoking (also during pregnancy), prematurity (including pulmonary infections, RDS and BPD), early viral respiratory infections (such as RSV-bronchiolitis), male gender, early lung function abnormalities and atopic constitution. The major risk factor for persistent BA is an underlying allergic constitution. Therefore, early symptoms and markers of allergy (i.e. The Allergic March) and a positive family history for allergy should be considered as important risk factors for the development of BA

Prenatal exposures and exposomics of asthma

This review examines the causal investigation of preclinical development of childhood asthma using exposomic tools. We examine the current state of knowledge regarding early-life exposure to non-biogenic indoor air pollution and the developmental modulation of the immune system. We examine how metabolomics technologies could aid not only in the biomarker identification of a particular asthma phenotype, but also the mechanisms underlying the immunopathologic process. Within such a framework, we propose alternate components of exposomic investigation of asthma in which, the exposome represents a reiterative investigative process of targeted biomarker identification, validation through computational systems biology and physical sampling of environmental medi

Allergotoxicology: Research of Pollutant Influence on the Development of Allergic Reactions

Alergotoksikologija je znanstvenoistraživačko područje koje se bavi ispitivanjem utjecaja polutanata (onečišćivača zraka) na nastanak alergijskih reakcija i bolesti. Ispitivanja su prvobitno bila usmjerena na polutante vanjskih prostora, a u novije vrijeme sve više na polutante unutarnjih prostora u kojima ljudi provode većinu vremena. Polutanti po svojoj prirodi mogu biti krute, tekuće ili plinovite čestice, koje se razlikuju s obzirom na veličinu, sastav i izvor iz kojeg nastaju. S obzirom na izvor mogu biti biološkog i nebiološkog podrijetla. Polutanti koji su predmet suvremenih istraživanja s gledišta nastanka alergijskih bolesti su respirabilne krute čestice, ozon, dušični oksidi i bioaerosoli. Mehanizam djelovanja polutanata ovisi o veličini čestica, njihovoj topljivosti i mjestu ulaska u organizam. Dosadašnja ispitivanja su pokazala da različite čestice uvjetuju različite imunosne i neimunosne odgovore u organizmu. Interakcija polutanata i alergena može se zbivati izvan eksponirane osobe, tj. sa samim alergenom ili u eksponiranoj osobi na sluznicama i koži. Polutanti mogu biti nosioci alergena i mogu interferirati na različitim nivoima u nastanku alergijske reakcije. U ovom prikazu razma raju se dosadašnja saznanja o mehanizmima djelovanja polutanata na alergene, na imunosni sustav izloženih osoba na osnovi epidemioloških populacijskih istraživanja, kliničkih studija ekspozcije u kontroliranim uvjetima i eksperimentalnih testnih sistema in vivo i in vitro.Allergotoxicology studies the infl uence of pollutants on the development of allergic reactions and diseases. At the beginning, the research was focused on outdoor air pollutants, while recently it turns to the indoor environment, mainly because people this is where people spend most of their time. Air pollutants may be solid, soluble, or gaseous particles in nature, and they can differ in size, structure, and sources. Pollutants can be of biological or nonbiological origin. Currently interesting air pollutants include particulate matter, ozone, nitrogen oxides, and bioaerosols. The mechanisms of pollutant activity depend on the particle size, solubility, site of deposition, and specifi c chemical properties. Recent studies have shown that different pollutants provoke different immunological and nonimmunological responses in exposed persons. Interaction between air pollutants and allergens can take place outside the exposed person i.e. with allergen itself, or inside the organism on mucous membranes and skin. Pollutants may be the carriers of allergens and may exacerbate allergic reactions and diseases. This review presents recent views about the mechanisms of pollutant activity on allergens and immune system response in exposed persons, based on epidemiological population studies, clinical studies of exposure under controlled conditions, and experimental tests in vitro and in vivo