A randomized control trial of nursing-based case management for patients with chronic obstructive pulmonary disease

This study assessed the impact of a randomized trial of nursing-based case management for patients with chronic obstructive pulmonary disease, their caregivers, and nursing and medical staff. Sixty-six patients were matched by FEV1 on admission to hospital, and randomized into an intervention or control group. Intervention group patients reported significantly less anxiety at 1 month postdischarge; however, this effect was not sustained. There was little difference between groups in terms of unplanned readmissions, depression, symptoms, support, and subjective well being. Interviews with patients and caregivers found that the case management improved access to resources and staff-patient communication. Interviews with nursing and medical staff found that case management improved communication between staff and enhanced patient care.

The prediction of sharkskin instability observed during film blowing

The characteristics of sharkskin surface instability for linear low density polyethylene are studied as a function of film blowing processing conditions. By means of scanning electron microscopy and surface profilometry, is it found that for the standard industrial die geometry studied, sharkskin only occurs on the inside of the film bubble. Previous work suggests that this instability may be due to critical extensional stress levels at the exit of the die. Isothermal integral viscoelastic simulations of the annular extrusion process are reported, and confirm that the extensional stress at the die exit is large enough to cause local melt rupture. However the extensional stress level at the outer die wall predicts melt rupture of the outside bubble surface also, which contradicts the experimental findings. A significant temperature gradient is expected to exist across the die gap at the exit of the die, due to the external heating of the die and the low conductivity, of the polymer melt. It is shown that a gradient of 20 degreesC is required to cause sharkskin to only appear on the inner bubble surface.

Telemedicine for new neurological outpatients: putting a randomized controlled trial in the context of everyday practice

In a retrospective review, the telemedical management of 65 outpatients from a randomized controlled trial (RCT) of telemedicine for non-urgent referrals to a consultant neurologist was compared with the management of 76 patients seen face to face in the same trial, with that of 150 outpatients seen in the neurology clinics of district general hospitals and with that of 102 neurological outpatients seen by general physicians. Outcome measures were the numbers of investigations and of patient reviews. The telemedicine group did not differ significantly from the 150 patients seen face to face by neurologists in hospital clinics in terms of either the number of investigations or the number of reviews they received. Patients from the RCT seen face to face had significantly fewer investigations but a similar number of reviews to the other 150 patients seen face to face by neurologists (the disparity in the number of investigations may explain the negative result for telemedicine in that RCT). Patients with neurological symptoms assessed by general physicians had significantly more investigations and were reviewed significantly more often than all the other groups. Patients from the RCT seen by telemedicine were not managed significantly differently from those seen face to face by neurologists in hospital clinics but had significantly fewer investigations and follow-ups than those patients managed by general physicians. The results suggest that management of new neurological outpatients by neurologists using telemedicine is similar to that by neurologists using a face-to-face consultation, and is more efficient than management by general physicians.

Estimation of total body water from bioelectrical impedance analysis in patients with pancreatic cancer - agreement between three methods of prediction

Introduction Bioelectrical impedance analysis (BIA) is a useful field measure to estimate total body water (TBW). No prediction formulae have been developed or validated against a reference method in patients with pancreatic cancer. The aim of this study was to assess the agreement between three prediction equations for the estimation of TBW in cachectic patients with pancreatic cancer. Methods Resistance was measured at frequencies of 50 and 200 kHz in 18 outpatients (10 males and eight females, age 70.2 +/- 11.8 years) with pancreatic cancer from two tertiary Australian hospitals. Three published prediction formulae were used to calculate TBW - TBWs developed in surgical patients, TBWca-uw and TBWca-nw developed in underweight and normal weight patients with end-stage cancer. Results There was no significant difference in the TBW estimated by the three prediction equations - TBWs 32.9 +/- 8.3 L, TBWca-nw 36.3 +/- 7.4 L, TBWca-uw 34.6 +/- 7.6 L. At a population level, there is agreement between prediction of TBW in patients with pancreatic cancer estimated from the three equations. The best combination of low bias and narrow limits of agreement was observed when TBW was estimated from the equation developed in the underweight cancer patients relative to the normal weight cancer patients. When no established BIA prediction equation exists, practitioners should utilize an equation developed in a population with similar critical characteristics such as diagnosis, weight loss, body mass index and/or age. Conclusions Further research is required to determine the accuracy of the BIA prediction technique against a reference method in patients with pancreatic cancer.

Polyethylene flow prediction with a differential multi-mode Pom-Pom model

We report the first steps of a collaborative project between the University of Queensland, Polyflow, Michelin, SK Chemicals, and RMIT University; on simulation, validation and application of a recently introduced constitutive model designed to describe branched polymers. Whereas much progress has been made on predicting the complex flow behaviour of many - in particular linear - polymers, it sometimes appears difficult to predict simultaneously shear thinning and extensional strain hardening behaviour using traditional constitutive models. Recently a new viscoelastic model based on molecular topology, was proposed by McLeish and Larson (1998). We explore the predictive power of a differential multi-mode version of the pom-pom model for the flow behaviour of two commercial polymer melts: a (long-chain branched) low-density polyethylene (LDPE) and a (linear) high-density polyethylene (HDPE). The model responses are compared to elongational recovery experiments published by Langouche and Debbaut (1999), and start-up of simple shear flow, stress relaxation after simple and reverse step strain experiments carried out in our laboratory.

Randomized comparison of the quality of realtime fetal ultrasound images transmitted by ISDN and by IP videoconferencing

We compared the quality of realtime fetal ultrasound images transmitted using ISDN and IP networks. Four experienced obstetric ultrasound specialists viewed standard recordings in a randomized trial and rated the appearance of 30 fetal anatomical landmarks, each on a seven-point scale. A total of 12 evaluations were performed for various combinations of bandwidths (128, 384 or 768 kbit/s) and networks (ISDN or IF). The intraobserver coefficient of variation was 2.9%, 5.0%, 12.7% and 14.7% for the four observers. The mean overall ratings by each of the four observers were 4.6, 4.8, 5.0 and 5.3, respectively (a rating of 4 indicated satisfactory visualization and 7 indicated as good as the original recording). Analysis of variance showed that there were no significant interobserver variations nor significant differences in the mean scores for the different types of videoconferencing machines used. The most significant variable affecting the mean score was the bandwidth used. For ISDN, the mean score was 3.7 at 128 kbit/s, which was significantly worse than the mean score of 4.9 at 384 kbit/s, which was in turn significantly worse than the mean score of 5.9 at 768 kbit/s. The mean score for transmission using IP was about 0.5 points lower than that using ISDN across all the different bandwidths, but the differences were not significant. It appears that IP transmission in a private (non-shared) network is an acceptable alternative to ISDN for fetal tele-ultrasound and one deserving further study.

Stress correlation function evolution in lattice solid elasto-dynamic models of shear and fracture zones and earthquake prediction

It has been argued that power-law time-to-failure fits for cumulative Benioff strain and an evolution in size-frequency statistics in the lead-up to large earthquakes are evidence that the crust behaves as a Critical Point (CP) system. If so, intermediate-term earthquake prediction is possible. However, this hypothesis has not been proven. If the crust does behave as a CP system, stress correlation lengths should grow in the lead-up to large events through the action of small to moderate ruptures and drop sharply once a large event occurs. However this evolution in stress correlation lengths cannot be observed directly. Here we show, using the lattice solid model to describe discontinuous elasto-dynamic systems subjected to shear and compression, that it is for possible correlation lengths to exhibit CP-type evolution. In the case of a granular system subjected to shear, this evolution occurs in the lead-up to the largest event and is accompanied by an increasing rate of moderate-sized events and power-law acceleration of Benioff strain release. In the case of an intact sample system subjected to compression, the evolution occurs only after a mature fracture system has developed. The results support the existence of a physical mechanism for intermediate-term earthquake forecasting and suggest this mechanism is fault-system dependent. This offers an explanation of why accelerating Benioff strain release is not observed prior to all large earthquakes. The results prove the existence of an underlying evolution in discontinuous elasto-dynamic, systems which is capable of providing a basis for forecasting catastrophic failure and earthquakes.

Load-unload response ratio and accelerating moment/energy release critical region scaling and earthquake prediction

The main idea of the Load-Unload Response Ratio (LURR) is that when a system is stable, its response to loading corresponds to its response to unloading, whereas when the system is approaching an unstable state, the response to loading and unloading becomes quite different. High LURR values and observations of Accelerating Moment/Energy Release (AMR/AER) prior to large earthquakes have led different research groups to suggest intermediate-term earthquake prediction is possible and imply that the LURR and AMR/AER observations may have a similar physical origin. To study this possibility, we conducted a retrospective examination of several Australian and Chinese earthquakes with magnitudes ranging from 5.0 to 7.9, including Australia's deadly Newcastle earthquake and the devastating Tangshan earthquake. Both LURR values and best-fit power-law time-to-failure functions were computed using data within a range of distances from the epicenter. Like the best-fit power-law fits in AMR/AER, the LURR value was optimal using data within a certain epicentral distance implying a critical region for LURR. Furthermore, LURR critical region size scales with mainshock magnitude and is similar to the AMR/AER critical region size. These results suggest a common physical origin for both the AMR/AER and LURR observations. Further research may provide clues that yield an understanding of this mechanism and help lead to a solid foundation for intermediate-term earthquake prediction.

Prediction of Golgi Type II membrane proteins based on their transmembrane domains

Motivation: A major issue in cell biology today is how distinct intracellular regions of the cell, like the Golgi Apparatus, maintain their unique composition of proteins and lipids. The cell differentially separates Golgi resident proteins from proteins that move through the organelle to other subcellular destinations. We set out to determine if we could distinguish these two types of transmembrane proteins using computational approaches. Results: A new method has been developed to predict Golgi membrane proteins based on their transmembrane domains. To establish the prediction procedure, we took the hydrophobicity values and frequencies of different residues within the transmembrane domains into consideration. A simple linear discriminant function was developed with a small number of parameters derived from a dataset of Type II transmembrane proteins of known localization. This can discriminate between proteins destined for Golgi apparatus or other locations (post-Golgi) with a success rate of 89.3% or 85.2%, respectively on our redundancy-reduced data sets.

A Pilot Randomized Trial Comparing CD-34Selected Versus Unmanipulated Hemopoietic Stem Cell Transplantation for Severe, Refractory Rheumatoid Arthritis

Objective. Evidence from animal studies, case reports, and phase I studies suggests that hemopoietic stem cell transplantation (HSCT) can be effective in the treatment of rheumatoid arthritis (RA). It is unclear, however, if depletion of T cells in the stem cell product infused after high-dose chemotherapy is beneficial in prolonging responses by reducing the number of infused autoreactive T cells. This pilot multicenter, randomized trial was undertaken to obtain feasibility data on whether CD34 selection (as a form of T cell depletion) of an autologous stem cell graft is of benefit in the HSCT procedure in patients with severe, refractory RA. Methods. Thirty-three patients with severe RA who had been treated unsuccessfully with methotrexate and at least 1 other disease-modifying agent were enrolled in the trial. The patients received high-dose immunosuppressive treatment with 200 mg/kg cyclophosphamide followed by an infusion of autologous stem cells that were CD34 selected or unmanipulated. Safety, efficacy (based on American College of Rheumatology [ACR] response criteria), and time to recurrence of disease were assessed on a monthly basis for up to 12 months. Results. All patients were living at the end of the study, with no major unexpected toxicities. Overall, on an intent-to-treat basis, ACR 20% response (ACR20) was achieved in 70% of the patients. An ACR70 response was attained in 27.7% of the 18 patients who had received CD34-selected cells and 53.3% of the 15 who had received unmanipulated cells (P = 0.20). The median time to disease recurrence was 147 days in the CD34-selected cell group and 201 days in the unmanipulated cell group (P = 0.28). There was no relationship between CD4 lymphopenia and response, but 72% of rheumatoid factor (RF)-positive patients had an increase in RF titer prior to recurrence of disease. Conclusion. HSCT can be performed safely in patients with RA, and initial results indicate significant responses in patients with severe, treatment-resistant disease. Similar outcomes were observed in patients undergoing HSCT with unmanipulated cells and those receiving CD34-selected cells. Larger studies are needed to confirm these findings.