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Oxygen for breathlessness in patients with chronic obstructive pulmonary disease who do not qualify for home oxygen therapy

Background: Breathlessness is a cardinal symptom of chronic obstructive pulmonary disease (COPD). Long-term oxygen therapy (LTOT) is given to improve survival time in people with COPD and severe chronic hypoxaemia at rest. The efficacy of oxygen therapy for breathlessness and health-related quality of life (HRQOL) in people with COPD and mild or no hypoxaemia who do not meet the criteria for LTOT

Path loss models with distance-dependent weighted fitting and estimation of censored path loss data

Path loss models are the most fundamental part of wireless propagation channel models. Path loss is typically modelled as a (single-slope or multi-slope) power-law dependency on distance plus a log-normally distributed shadowing attenuation. Determination of the parameters of this model is usually done by fitting the model to results from measurements or ray tracing. The authors show that the typi

Confinement effects on Brillouin scattering in semiconductor nanowire photonic crystal

Scattering of photons by phonons, or Brillouin scattering, enables manipulation and control of light and has led to revolutionary applications, from slow light to saser and cooling of micromechanical resonators. Recently, enhanced light and sound interaction has been demonstrated in waveguides. However, the design of the waveguide geometry tunes and alters the phonon and photon dispersion simultan

Histone acetylation of glucose-induced thioredoxin-interacting protein gene expression in pancreatic islets

Thioredoxin-interacting protein (TXNIP) has been shown to be associated with glucose-induced deterioration of pancreatic beta cell function in diabetes. However, whether epigenetic mechanisms contribute to the regulation of TXNIP gene expression by glucose is not clear. Here we studied how glucose exerts its effect on TXNIP gene expression via modulation of histone acetylation marks. To achieve th

miR-23b regulates cytoskeletal remodeling, motility and metastasis by directly targeting multiple transcripts

Uncontrolled cell proliferation and cytoskeletal remodeling are responsible for tumor development and ultimately metastasis. A number of studies have implicated microRNAs in the regulation of cancer cell invasion and migration. Here, we show that miR-23b regulates focal adhesion, cell spreading, cell-cell junctions and the formation of lamellipodia in breast cancer (BC), implicating a central role

5-HT-like immunoreactivity in the central nervous system of the crayfish Pacifastacus leniusculus

An immunocytochemical technique with the use of three different antibodies raised against serotonin was applied to localize the immunoreactive neurons in the central nervous system of the crayfish, Pacifastacus leniusculus. Immunoreactive neurons were found in three optic ganglia (medulla externa, interna and terminalis). They appeared in three layers of the medulla externa and interna. The medull

Enhanced priming of old, not new soil carbon at elevated atmospheric CO2

Rising atmospheric CO2 concentrations accompanied by global warming and altered precipitation patterns calls for assessment of long-term effects of these global changes on carbon (C) dynamics in terrestrial ecosystems, as changes in net C exchange between soil and atmosphere will impact the atmospheric CO2 concentration profoundly. In many ecosystems, including the heath/grassland system studied h

Colour reconnection - Models and tests

Recent progress on colour reconnection within the Pythia framework is presented. A new model is introduced, based on the SU(3) structure of QCD and a minimization of the potential string energy. The inclusion of the epsilon structure of SU(3) gives a new baryon production mechanism and makes it possible simultaneously to describe hyperon production at both e+e- and pp colliders. Finally, predictio

Accuracy of borehole thermal resistance calculation methods for grouted single U-tube ground heat exchangers

The borehole thermal resistance – that is, the thermal resistance between the fluid in the U-tube and the borehole wall – is both a key performance characteristic of a closed-loop borehole ground heat exchanger and an important design parameter. Lower borehole thermal resistance leads to better system performance and/or lower total borehole length and possibly lower installation costs. Borehole th

The HIF-2alpha-Driven Pseudo-Hypoxic Phenotype in Tumor Aggressiveness, Differentiation, and Vascularization.

Cellular adaptation to diminished tissue oxygen tensions, hypoxia, is largely governed by the hypoxia inducible transcription factors, HIF-1 and HIF-2. Tumor hypoxia and high HIF protein levels are frequently associated with aggressive disease. In recent years, high tumor cell levels of HIF-2 and the oxygen sensitive subunit HIF-2alpha have been associated with unfavorable disease and shown to be

Rate-ratio asymptotic analysis of the influence of stoichiometric mixture fraction on structure and extinction of laminar, nonpremixed methane flames with comparison to experiments

Activation energy asymptotic analysis and rate-ratio asymptotic analysis of combustion in laminar, nonpremixed flames are often carried out using conserved scalar quantities as independent variables. One such representation of a conserved scalar quantity is the mixture fraction, ξ, based on thermal diffusivity. These analyses are carried out in the asymptotic limit of large Damköhler number, with

Investigations of Hematopoietic Stem Cells and Their Age-Associated Alterations

The hematopoietic stem cell (HSC) has and continues to be extensively investigated, and represents by far the most studied somatic stem cell. Development of various experimental technologies, including fluorescence activated cell sorting (FACS), have been crucial for research advancements within the hematopoietic field. However, utilization of flow cytometry techniques put high demands on study deThe hematopoietic stem cell (HSC) has and continues to be extensively investigated, and represents by far the most studied somatic stem cell. Development of various experimental technologies, including fluorescence activated cell sorting (FACS), have been crucial for research advancements within the hematopoietic field. However, utilization of flow cytometry techniques put high demands on study de