Tree Productivity Enhanced with Conversion from Forest to Urban Land Covers.

Urban areas are expanding, changing the structure and productivity of landscapes. While some urban areas have been shown to hold substantial biomass, the productivity of these systems is largely unknown. We assessed how conversion from forest to urban land uses affected both biomass structure and productivity across eastern Massachusetts. We found that urban land uses held less than half the biomass of adjacent forest expanses with a plot level mean biomass density of 33.5 ± 8.0 Mg C ha(-1). As the intensity of urban development increased, the canopy cover, stem density, and biomass decreased. Analysis of Quercus rubra tree cores showed that tree-level basal area increment nearly doubled following development, increasing from 17.1 ± 3.0 to 35.8 ± 4.7 cm(2) yr(-1). Scaling the observed stem densities and growth rates within developed areas suggests an aboveground biomass growth rate of 1.8 ± 0.4 Mg C ha(-1) yr(-1), a growth rate comparable to nearby, intact forests. The contrasting high growth rates and lower biomass pools within urban areas suggest a highly dynamic ecosystem with rapid turnover. As global urban extent continues to grow, cities consider climate mitigation options, and as the verification of net greenhouse gas emissions emerges as critical for policy, quantifying the role of urban vegetation in regional-to-global carbon budgets will become ever more important.

Validity of predicting mean arterial blood pressure during exercise.

PURPOSE: Mean arterial blood pressure (mean arterial pressure (MAP)) at rest is conventionally estimated as the product of the diastolic pressure plus one-third of the pulse pressure. Since pulse wave forms and the duration of diastole change during exercise, one might question the validity of this prediction equation for the exercise state. Our purpose was to test this by directly measuring blood pressure over a wide range of exercise intensities. METHODS: Pressure was recorded by arterial catheterization in 29 subjects performing progressive exercise and/or constant-load exercise at different intensities. Actual MAP was measured by integrating the area under the pulse curve and compared it with the value which was predicted from systolic and diastolic measures over heart rates ranging from 100 to 200 beats x min(-1). RESULTS: Predicted values were quite close to actual MAP, and the accuracy of the prediction equation changed minimally with increased exercise intensity. CONCLUSION: This method provides a valid estimation of MAP during exercise.

Information overload: opportunities and challenges for the GP's desktop.

Recent developments in health data networks, the health sector and information systems, have created an overload of information available to the General Practitioner. The implementation of viable Health Data Networks within hospitals and subsequent connection to the GP's desktop PC enables increased access to patient records, decision-support and communication with experts around the world To address the high usage of expensive health services and lengthy waiting lists health services around the world are embracing programs such as Community, Coordinated, Shared and Managed care. This focus on coordination of care and increased emphasis on evidenced-based medicine is greatly enhanced through the advent of viable health data networks. Other resources such as databases, best-practice guidelines, the web, email, telemedicine and a range of commercial programs that provide further services has created an overload of resources available to the GP. Current human-computer interface guidelines are not adequate for prescribing design solutions to deal with the information overload facing GPs. The challenge for the near future is to present the vast array of information sources to the GP in an acceptable and useable information system interface. Part of the solution may revolve around the development of standards for Electronic Health Record systems for GPs, as is being done currently in Australia; but we suspect that less mainstream interface technologies will be required to exploit the wealth of available healthcare information.

Patient information provision: its effect on patient anxiety and the role of health information services and libraries.

This article is concerned with the importance of communicating information to patients as an aid to recovery by decreasing anxiety. Recent research suggests that pre-operative information helps to decrease post-operative stress and leads to a quicker recovery. The health belief model has proven to be an effective predictor of individuals' responses towards health-related matters. It is described as a useful theoretical framework for medical professionals in deciding the content and quantity of information that each patient should receive. A study for further research is suggested, exploring the hypothesis that reading about illness significantly helps to reduce anxiety when the patient has added emotional support from a health professional. The existing problem of who is ultimately responsible for giving information to patients is highlighted in the general practice, hospital and public settings. Recommendations are made for the improvement of patient information provision in these three areas. Librarians are seen as being in a good position to liaise with medical professionals to provide the most effective health information service possible for patients and the consumer in general.

The significance of fat and muscle areas in the lumbar paraspinal space: a CT study.

OBJECTIVE: The object of this study was to determine the significance of fat deposition and muscle dimensions on CT in the unoperated lumbar paraspinal space. MATERIALS AND METHODS: Fifty patients were prospectively studied. Paraspinal fat (PSF) and muscle (PSM) areas were correlated with various demographic and anatomical variables in patients with and without low back pain. The fat and muscle areas were derived from a standard CT image using a thresholding technique. RESULTS: Regression equations indicated that the total amount of PSF increases with age and subcutaneous fat area. The PSM area decreases with age. There was no correlation with the other variables examined. CONCLUSION: We conclude that PSF deposition and PSM dimensions on CT are related to patient age and the amount of subcutaneous fat. Paraspinal fat deposition is not a sign of muscle atrophy, and neither parameter is related to low back pain symptoms. Therefore, in patients who have not undergone spinal surgery, PSF and PSM areas are not of clinical or functional significance.

A blood grouping and antibody screening system using image analysis.

An effective, modular automated blood grouping system has been developed which performs more effectively than the AG16C autogroupers and which uses readily obtainable reagents and disposables. Operating and maintenance costs are low by comparison with currently available equipment of similar capacity. The 99.2% success rate for blood grouping using this image analysis-based system compares well with the 98.3% success rate on the AG16C autogroupers. Staffing requirements are reduced and the flexible modular approach allows this Newcastle system to be used for a range of serological functions, including grouping, antibody screening and screening for antigen donors. The ability to operate with small sample numbers without long start-up times and the relatively low capital cost makes the Newcastle system an option that could be considered by the larger hospitals as well as transfusion centres. The sensitivity of the system could be developed to include compatibility testing as a feature of the system.