Local CIP stabilization for composite finite elements

We propose a continuous interior penalty (CIP) method for the pure transport problem and for the viscosity dependent "Stokes-Brinkman" problem where the gradient jump penalty is localized to faces in the interior of subdomains. Special focus is given to the case where the subdomains are so-called composite finite elements, e.g., quadrilateral, hexahedral or prismatic elements which are composed by simplices such that the arising global simplicial mesh is regular. The advantage of this local CIP is that it allows for static condensation in contrast to the classical CIP method. If the degrees of freedom in the interior of the composite finite elements are eliminated using static condensation then the resulting couplings of the skeleton degrees of freedom are comparable to those for classical conforming finite element methods which leads to a substantially smaller matrix stencil than for the standard global CIP method. Optimal stability and error estimates are proved and numerical tests are presented. For the Stokes-Brinkman model, our error bound does not increase if the viscosity parameter tends to zero which is mainly achieved by adding a penalty term for the divergence of the velocity in the discretization. Moreover, the reduction effect of the static condensation is much stronger for this model since, beside the elimination of all velocity degrees of freedom in the interior of each composite cell, all pressure degrees of freedom except for the cellwise constants can be eliminated

Low-pressure fabric hyperbaric chambers

Hyperbaric oxygen therapy is defined as an intervention in which an individual breathes near 100% oxygen while wholly enclosed inside a hyperbaric chamber at a pressure ≥1.4 atmosphere absolute (ATA). The Southern African Underwater and Hyperbaric Medical Association (SAUHMA)-approved indications commence at pressures ≥2 ATA. Low-pressure hyperbaric chambers, at pressures ≤1.4 ATA, are approved for acute mountain sickness only. Mild hyperbaric exposures with air deliver no more oxygen to the body than breathing oxygen by mask at sea level pressure. Exposure to treatment pressures <2.0 ATA while breathing air does not meet the SAUHMA definition of therapeutic hyperbaric oxygen therapy and does not achieve the minimum pressure and oxygen levels required for any SAUHMA-approved indication. All SAUHMA-approved indications require that the patient breathe near 100% oxygen while enclosed in a chamber pressurised to a minimum of 2 ATA. SAUHMA does not recommend the use of mild hyperbaric therapy for any medical purpose other than acute mountain sickness

Numerical Computations with H(div)-Finite Elements for the Brinkman Problem

The H(div)-conforming approach for the Brinkman equation is studied numerically, verifying the theoretical a priori and a posteriori analysis in previous work of the authors. Furthermore, the results are extended to cover a non-constant permeability. A hybridization technique for the problem is presented, complete with a convergence analysis and numerical verification. Finally, the numerical convergence studies are complemented with numerical examples of applications to domain decomposition and adaptive mesh refinement.Comment: Minor clarifications, added references. Reordering of some figures. To appear in Computational Geosciences, final article available at http://www.springerlink.co

Lowpressure fabric hyperbaric chambers

Hyperbaric oxygen therapy is defined as an intervention in which an individual breathes near 100% oxygen while wholly enclosed inside a hyperbaric chamber at a pressure ≥1.4 atmosphere absolute (ATA). The Southern African Underwater and Hyperbaric Medical Association (SAUHMA)-approved indications commence at pressures ≥2 ATA. Low-pressure hyperbaric chambers, at pressures ≤1.4 ATA, are approved for acute mountain sickness only. Mild hyperbaric exposures with air deliver no more oxygen to the body than breathing oxygen by mask at sea level pressure. Exposure to treatment pressures <2.0 ATA while breathing air does not meet the SAUHMA definition of therapeutic hyperbaric oxygen therapy and does not achieve the minimum pressure and oxygen levels required for any SAUHMA-approved indication. All SAUHMA-approved indications require that the patient breathe near 100% oxygen while enclosed in a chamber pressurised to a minimum of 2 ATA. SAUHMA does not recommend the use of mild hyperbaric therapy for any medical purpose other than acute mountain sickness

Weakly Consistent Regularisation Methods for Ill-Posed Problems

This Chapter takes its origin in the lecture notes for a 9 h course at the Institut Henri Poincaré in September 2016. The course was divided in three parts. In the first part, which is not included herein, the aim was to first recall some basic aspects of stabilised finite element methods for convection-diffusion problems. We focus entirely on the second and third parts which were dedicated to ill-posed problems and their approximation using stabilised finite element methods. First we introduce the concept of conditional stability. Then we consider the elliptic Cauchy-problem and a data assimilation problem in a unified setting and show how stabilised finite element methods may be used to derive error estimates that are consistent with the stability properties of the problem and the approximation properties of the finite element space. Finally, we extend the result to a data assimilation problem subject to the heat equation

Hypercalcaemia and in vitro osteolysis associated with xenografts of squamous carcinomas of the tongue.

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Capturing the diversity of household window operation behaviour: Lessons from a monitoring campaign in London

The present study benefits from a field monitoring campaign across 18 flats in London to analyse the operation of windows by occupants and pinpoint the driving factors. The dataset covers an extensive set of environmental parameters including indoor and outdoor air temperature, relative humidity, CO2, PM2.5 and PM10 collected over non-heating and heating seasons. Focusing on three questions, this study a) captures the diversity of window operation across the flats using three metrics, b) identifies and ranks the driving factors behind the operation of windows, and c) discusses the diversity of these driving factors using univariate logistic regression models. Notably, the results suggest that, apart from the commonly studied factors such as air temperature and humidity, pollutant parameters can also explain the operation of windows by occupants. Furthermore, the diversity observed in the occupants’ window operation behaviour and its driving factors discourages the reliance of future modelling efforts on aggregated datasets that can suppress the inter-occupant diversity. More efforts are needed to further explore the potential benefits of the inclusion of the captured behavioural diversity information in occupant behaviour models for building performance simulations

Further observations on mechanisms of bone destruction by squamous carcinomas of the head and neck: the role of host stroma.

Mechanisms of bone invasion by squamous carcinomas of the head and neck have been investigated using fresh tumours and established tumour cell lines in an in vitro bone resorption assay with 45Ca-labelled mouse calvaria. Fresh tumours regularly resorb bone in vitro. Activity is consistently reduced by indomethacin. The tumours release E2 prostaglandins (PGE2) in amounts sufficient to account for approximately 50% of the bone resorption observed. Small amounts of non-prostaglandin (indomethacin-resistant) osteolytic factors are also produced. Control non-neoplastic tissues show a variable capacity to resorb bone in vitro; PGE2 levels in these tissues may be related to their content of inflammatory cells. Tumour cell lines also resorb bone in vitro but, for most lines, activity is not significantly blocked by indomethacin and PGE2 levels are generally insufficient to account for the osteolysis observed. Non-prostaglandin bone resorbing factors thus predominate. It is concluded that most squamous cancers of the head and neck are osteolytic in vitro and release a mixture of prostaglandin and non-prostaglandin factors which stimulate osteoclastic bone resorption. These factors are derived from both neoplastic and stromal elements, and are "tumour-associated" rather than "tumour-specific". In vitro bone resorption and prostaglandin release does not correlate with pathological features of the tumour or with post-operative survival

A study of the Zygaenidae (Lepidoptera) fauna of Central Anatolia, Turkey

The Zygaenidae fauna in some provinces (Aksaray, Karaman, Kayseri, Konya, Nevşehir and Niğde) of Central Anatolia was studied using attractant traps as well as by netting specimens in biotopes in 2017. The sex attractants for the Procridinae had been produced in the Crimean Federal University and were esters of 2 dodecenoic acid and isomers of 2-butanol: EFETOV-2 [racemic mixture of R- and S-enantiomers], EFETOV-S-2 [R-enantiomer] and EFETOV-S-S-2 [S-enantiomer]. Zygaena attractants were made at Canterbury Christ Church University using a range of acetate compounds with known attraction to various genera as originally identified by Priesner et al. (1984). Fourteen Zygaenidae species from four genera belonging to Procridinae and Zygaeninae subfamilies were found: Rhagades Wallengren, 1863 (1 species), Adscita Retzius, 1783 (1 species), Jordanita Verity, 1946 (4 species), and Zygaena Fabricius, 1775 (8 species)