The Cauchy problem for a class of two-dimensional nonlocal nonlinear wave equations governing anti-plane shear motions in elastic materials

This paper is concerned with the analysis of the Cauchy problem of a general class of two-dimensional nonlinear nonlocal wave equations governing anti-plane shear motions in nonlocal elasticity. The nonlocal nature of the problem is reflected by a convolution integral in the space variables. The Fourier transform of the convolution kernel is nonnegative and satisfies a certain growth condition at infinity. For initial data in $L^{2}$ Sobolev spaces, conditions for global existence or finite time blow-up of the solutions of the Cauchy problem are established.Comment: 15 pages. "Section 6 The Anisotropic Case" added and minor changes. Accepted for publication in Nonlinearit

An elastoplastic theory of dislocations as a physical field theory with torsion

We consider a static theory of dislocations with moment stress in an anisotropic or isotropic elastoplastical material as a T(3)-gauge theory. We obtain Yang-Mills type field equations which express the force and the moment equilibrium. Additionally, we discuss several constitutive laws between the dislocation density and the moment stress. For a straight screw dislocation, we find the stress field which is modified near the dislocation core due to the appearance of moment stress. For the first time, we calculate the localized moment stress, the Nye tensor, the elastoplastic energy and the modified Peach-Koehler force of a screw dislocation in this framework. Moreover, we discuss the straightforward analogy between a screw dislocation and a magnetic vortex. The dislocation theory in solids is also considered as a three-dimensional effective theory of gravity.Comment: 38 pages, 6 figures, RevTe

Transitional Care for Patients with Congenital Colorectal Diseases: An EUPSA Network Office, ERNICA, and eUROGEN Joint Venture

Background: Transition of care (TOC; from childhood into adulthood) of patients with anorectal malformations (ARM) and Hirschsprung disease (HD) ensures continuation of care for these patients. The aim of this international study was to assess the current status of TOC and adult care (AC) programs for patients with ARM and HD. Methods: A survey was developed by members of EUPSA, ERN eUROGEN, and ERNICA, including patient representatives (ePAGs), comprising of four domains: general information, general questions about transition to adulthood, and disease-specific questions regarding TOC and AC programs. Recruitment of centres was done by the ERNs and EUPSA, using mailing lists and social media accounts. Only descriptive statistics were reported. Results: In total, 82 centres from 21 different countries entered the survey. Approximately half of them were ERN network members. Seventy-two centres (87.8%) had a self-reported area of expertise for both ARM and HD. Specific TOC programs were installed in 44% of the centres and AC programs in 31% of these centres. When comparing centres, wide variation was observed in the content of the programs. Conclusion: Despite the awareness of the importance of TOC and AC programs, these programs were installed in less than 50% of the participating centres. Various transition and AC programs were applied, with considerable heterogeneity in implementation, content and responsible caregivers involved. Sharing best practice examples and taking into account local and National Health Care Programs might lead to a better continuation of care in the future. Level of Evidence: III

Chemical composition testing of aerosol spray in the “Wieliczka” Salt Mine using the “scrubbing” method

Subterraneoterapia (speleoterapia) stosowana jest w leczeniu przewlekłych chorób układu oddechowego. Jednym z czynników leczniczych występujących w atmosferze podziemnej Uzdrowiska Kopalnia Soli „Wieliczka” jest obecność aerozolu solnego. Ma on działanie osmotyczne, zwiększa aktywność ruchu migawkowego rzęsek nabłonka oskrzeli i pobudza czynność wydzielniczą dróg oddechowych. W dniach 29.03 – 04.04.2017 roku w kompleksie komór Uzdrowiska Kopalnia Soli „Wieliczka” przeprowadzono badanie powietrza metodą aspiracyjną z wykorzystaniem płuczek. W pobranych próbkach dokonano pomiaru stężenia jonów: Cl-, NO3 -, PO4 3-, SO4 2-, F-, Na+, NH4 +, K+, Ca2+, Mg2+. Stężenie składników mineralnych w powietrzu podziemnym wyniosło od 2,7 – 8,1 mg/m3 - średnio we wszystkich próbach 4,4 mg/m3. W pobranych próbkach powietrza dochodzącego do kompleksu komór uzdrowiskowych wśród oznaczonych składników dominowały: sód, potas, wapń i chlorki. Stężenie aerozolu w granicach oznaczonych aktualnie jest porównywalne z aerozolem nadmorskim. Aerozol wytwarzany obiektach subterraneoterapii charakteryzuje bardzo niska zawartość składników nierozpuszczalnych. Warunki panujące w podziemnym kompleksie komór uzdrowiskowych, sprzyjają działalności leczniczej ukierunkowanej na leczenie przewlekłych schorzeń układu oddechowego.Subterraneotherapy (speleotherapy) is used in the treatment of chronic respiratory diseases. Salt aerosol is one of the therapeutic agents that occur in the underground atmosphere of the “Wieliczka” Salt Mine. It has an osmotic effect, increases the activity of the ciliary movement of the bronchial epithelium and stimulates respiratory secretion. In the period between 29th March and 4th April 2017, the air in the complex of the “Wieliczka” Salt Mine chambers was tested using the aspiration method with scrubbers. The measurements of ionic concentrations for Cl-, NO3 -, PO4 3-, SO4 2-, F-, Na+, NH4 +, K+, Ca2+, Mg2+ were followed by an analysis of the elements in the samples. In all samples, the concentration of minerals in the underground air was from 2.7 to 8.1 mg/m3- 4.4 mg/m3 on average. Sodium, potassium, calcium and chloride were dominant in the samples of air coming from the complex of spa chambers. The currently determined concentration of aerosol is comparable to coastal aerosol. Aerosol produced by subterraneotherapy objects has a very low content of insoluble constituents. The conditions in the underground complex of the spa chambers are beneficial to therapeutic activities aimed at treating chronic respiratory diseases