Age-Related Health Hazards in Old Patients with First-Time Referral to a Rheumatologist: A Descriptive Study

Objective. To study the prevalence of generic age-related health hazards in elderly patient referred to a rheumatologist. Methods. Patients aged 75 or older referred to a specialized gerontorheumatological outpatient service over a period of 2 years were studied prospectively to determine the prevalence of comorbidities, a history of falls, inactivity, cognitive dysfunction, loneliness, and depression in this patient group. Results. A group of 154 patients were included in the study. Comorbidities were observed in 88% of the patients. At least one fall was reported in the last year by 44% of the patients; 44% of the patients reported low levels of health-enhancing physical activity. Depressed mood and loneliness were elevated in 30% and 31% of the patients, respectively. Mild or moderate cognitive impairment was observed in 13% of the patients. Conclusion. Patients in this study were characterized by poor physical ability, high levels of pain, and high prevalence of age-related health hazards

An Endothelial Storage Granule for Tissue-Type Plasminogen Activator

In previous studies we have shown that, after stimulation by a receptor ligand such as thrombin, tissue-type plasminogen activator (tPA) and von Willebrand factor (vWf) will be acutely released from human umbilical vein endothelial cells (HUVEC). However, the mechanisms involved in the secretion of these two proteins differ in some respects, suggesting that the two proteins may be stored in different secretory granules

Brane-world Cosmologies with non-local bulk effects

It is very common to ignore the non-local bulk effects in the study of brane-world cosmologies using the brane-world approach. However, we shall illustrate through the use of three different scenarios, that the non-local bulk-effect ${\cal P}_{\mu\nu}$ does indeed have significant impact on both the initial and future behaviour of brane-world cosmologies.Comment: 17 pages, no figures, iopart.cls, submitted to CQ

The Dynamics of Multi-Scalar Field Cosmological Models and Assisted Inflation

We investigate the dynamical properties of a class of spatially homogeneous and isotropic cosmological models containing a barotropic perfect fluid and multiple scalar fields with independent exponential potentials. We show that the assisted inflationary scaling solution is the global late-time attractor for the parameter values for which the model is inflationary, even when curvature and barotropic matter are included. For all other parameter values the multi-field curvature scaling solution is the global late-time attractor (in these solutions asymptotically the curvature is not dynamically negligible). Consequently, we find that in general all of the scalar fields in multi-field models with exponential potentials are non-negligible in late-time behaviour, contrary to what is commonly believed. The early-time and intermediate behaviour of the models is also studied. In particular, n-scalar field models are investigated and the structure of the saddle equilibrium points corresponding to inflationary m-field scaling solutions and non-inflationary m-field matter scaling solutions are also studied (where m<n), leading to interesting transient dynamical behaviour with new physical scenarios of potential importance.Comment: 27 pages, uses REVTeX Added an appendix illustrating some of the details needed to compute the stability of the assisted inflationary solutio

Self-similar spherically symmetric cosmological models with a perfect fluid and a scalar field

Self-similar, spherically symmetric cosmological models with a perfect fluid and a scalar field with an exponential potential are investigated. New variables are defined which lead to a compact state space, and dynamical systems methods are utilised to analyse the models. Due to the existence of monotone functions global dynamical results can be deduced. In particular, all of the future and past attractors for these models are obtained and the global results are discussed. The essential physical results are that initially expanding models always evolve away from a massless scalar field model with an initial singularity and, depending on the parameters of the models, either recollapse to a second singularity or expand forever towards a flat power-law inflationary model. The special cases in which there is no barotropic fluid and in which the scalar field is massless are considered in more detail in order to illustrate the asymptotic results. Some phase portraits are presented and the intermediate dynamics and hence the physical properties of the models are discussed.Comment: 31 pages, 4 figure

Reproductive competition between polygynous parasite queens in ant colonies

BACKGROUND: Evaluation of percutaneous tracheostomy (PT) with the guide wire dilating forceps (GWDF) technique. METHODS: Prospective study of perioperative complications, retrospective analysis of early and late complications in an ICU in a teaching university hospital. RESULTS: The success rate of the procedure was 96.5%. The average procedure time in 171 consecutive patients was 5.0 min. Perioperative complications requiring surgical or medical intervention occurred in 6.4% of 171 patients. This included conversion to surgical tracheostomy, which was necessary in six patients (3.5%). Major complications while being cannulated occurred in 2.4% of 164 patients but seemed mostly unrelated with the GWDF technique itself. Late complications (after decannulation) were mostly minor and occurred in 22.6% of 106 patients. Only one patient (0.9%) had a symptomatic tracheal stenosis developed. CONCLUSION: Percutaneous tracheostomy with the guide wire dilating forceps technique is easy to perform at the bedside with few late complications. However, in our study, perioperative and immediate postoperative bleeding complications (minor and major) occur quite often

Local and non-local measures of acceleration in cosmology

Current cosmological observations, when interpreted within the framework of a homogeneous and isotropic Friedmann-Lemaitre-Robertson-Walker (FLRW) model, strongly suggest that the Universe is entering a period of accelerating expansion. This is often taken to mean that the expansion of space itself is accelerating. In a general spacetime, however, this is not necessarily true. We attempt to clarify this point by considering a handful of local and non-local measures of acceleration in a variety of inhomogeneous cosmological models. Each of the chosen measures corresponds to a theoretical or observational procedure that has previously been used to study acceleration in cosmology, and all measures reduce to the same quantity in the limit of exact spatial homogeneity and isotropy. In statistically homogeneous and isotropic spacetimes, we find that the acceleration inferred from observations of the distance-redshift relation is closely related to the acceleration of the spatially averaged universe, but does not necessarily bear any resemblance to the average of the local acceleration of spacetime itself. For inhomogeneous spacetimes that do not display statistical homogeneity and isotropy, however, we find little correlation between acceleration inferred from observations and the acceleration of the averaged spacetime. This shows that observations made in an inhomogeneous universe can imply acceleration without the existence of dark energy.Comment: 19 pages, 10 figures. Several references added or amended, some minor clarifications made in the tex