Ecosystem process models at multiple scales for mapping tropical forest productivity

Quantifying mass and energy exchanges within tropical forests is essential for understanding their role in the global carbon budget and how they will respond to perturbations in climate. This study reviews ecosystem process models designed to predict the growth and productivity of temperate and tropical forest ecosystems. Temperate forest models were included because of the minimal number of tropical forest models. The review provides a multiscale assessment enabling potential users to select a model suited to the scale and type of information they require in tropical forests. Process models are reviewed in relation to their input and output parameters, minimum spatial and temporal units of operation, maximum spatial extent and time period of application for each organization level of modelling. Organizational levels included leaf-tree, plot-stand, regional and ecosystem levels, with model complexity decreasing as the time-step and spatial extent of model operation increases. All ecosystem models are simplified versions of reality and are typically aspatial. Remotely sensed data sets and derived products may be used to initialize, drive and validate ecosystem process models. At the simplest level, remotely sensed data are used to delimit location, extent and changes over time of vegetation communities. At a more advanced level, remotely sensed data products have been used to estimate key structural and biophysical properties associated with ecosystem processes in tropical and temperate forests. Combining ecological models and image data enables the development of carbon accounting systems that will contribute to understanding greenhouse gas budgets at biome and global scales.

Identification of "pathologs" (disease-related genes) from the RIKEN mouse cDNA dataset using human curation plus FACTS, a new biological information extraction system

Background: A major goal in the post-genomic era is to identify and characterise disease susceptibility genes and to apply this knowledge to disease prevention and treatment. Rodents and humans have remarkably similar genomes and share closely related biochemical, physiological and pathological pathways. In this work we utilised the latest information on the mouse transcriptome as revealed by the RIKEN FANTOM2 project to identify novel human disease-related candidate genes. We define a new term patholog to mean a homolog of a human disease-related gene encoding a product ( transcript, anti-sense or protein) potentially relevant to disease. Rather than just focus on Mendelian inheritance, we applied the analysis to all potential pathologs regardless of their inheritance pattern. Results: Bioinformatic analysis and human curation of 60,770 RIKEN full-length mouse cDNA clones produced 2,578 sequences that showed similarity ( 70 - 85% identity) to known human-disease genes. Using a newly developed biological information extraction and annotation tool ( FACTS) in parallel with human expert analysis of 17,051 MEDLINE scientific abstracts we identified 182 novel potential pathologs. Of these, 36 were identified by computational tools only, 49 by human expert analysis only and 97 by both methods. These pathologs were related to neoplastic ( 53%), hereditary ( 24%), immunological ( 5%), cardio-vascular (4%), or other (14%), disorders. Conclusions: Large scale genome projects continue to produce a vast amount of data with potential application to the study of human disease. For this potential to be realised we need intelligent strategies for data categorisation and the ability to link sequence data with relevant literature. This paper demonstrates the power of combining human expert annotation with FACTS, a newly developed bioinformatics tool, to identify novel pathologs from within large-scale mouse transcript datasets.

Falls prevention in rural general practice: what stands the test of time and where to from here?

Objective: General practitioner recall of the 1992-96 'Stay on Your Feet'(SOYF) program and its influence on practice were surveyed five years post-intervention to gauge sustainability of the SOYF General Practice (GP) component. Methods: A survey assessed which SOYF components were still in existence, current practice related to falls prevention, and interest in professional development. All general practitioners (GPs) situated within the boundaries of a rural Area Health Service were mailed a survey in late 2001. Results: Response rate was 66.5% (139/ 209). Of 117 GPs in practice at the time of SOYF, 80.2% reported having heard of SOYF and 74.4% of those felt it had influenced practice. Half (50.9%) still had a copy of the SOYF GP resource and of those, 58.6% used it at least 'occasionally'. Three-quarters of GPs surveyed (75.2%) checked medications 'most/almost all' of the time with patients over 60 years; 46.7% assessed falls risk factors; 41.3% gave advice; and 22.6% referred to allied health practitioners. GPs indicated a strong interest in falls prevention- related professional development. There was no significant association between use of the SOYF resource package and any of the current falls prevention practices (all chi(2)>0.05). Conclusions and implications: There was high recall of SOYF and a general belief that it influenced practice. There was little indication that use of the resource had any lasting influence on GPs' practices. In future, careful thought needs to go into designing a program that has potential to affect long-term change in GPs' falls prevention practice.

Electronic medical records may be inadequate for improving population health status through general practice: cervical smears as a case study

Objective: To determine whether routine electronic records are an accurate source of population health data in general practice through reviewing cervical smears rates in four South Australian practices. Methods: The cervical screening rate in a purposive sample of four general practices (three rural and one urban) was obtained using an audit of medical records and a telephone follow-up. Results: The cervical screening rate using only immediately available electronic medical records indicated an overall low rate for the participating practices (44.9%). However, telephone follow-up and adjustments to the denominator indicated the real rate to be 85.7%. The offer of appointments during the telephone follow-up further improved this rate for eligible women (93.8%). Conclusions and implications: Electronic medical records may be inadequate in preventive screening in general practice, without ensuring their accuracy. Updating records by telephone or personal follow-up produces a much more accurate denominator.

Improving access to evidence-based mental health care: general practitioners and allied health professionals collaborate

This study evaluated whether projects conducted through the Access to Allied Health Services component of the Australian Better Outcomes in Mental Health Care initiative are improving access to evidence-based, non-pharmacological therapies for people with depression and anxiety. Synthesising data from the first 29 projects funded through the initiative, the study found that the models utilised in the projects have evolved over time. The projects have achieved a high level uptake; at a conservative estimate, 710 GPs and 160 allied health professionals (AHPs) have provided care to 3,476 consumers. The majority of these consumers have depression (77%) and/or anxiety disorders (55%); many are low income earners (57%); and a number have not previously accessed mental health care (40%). The projects have delivered 8,678 sessions of high quality care to these consumers, most commonly providing CBT-based cognitive and behavioural interventions (55% and 41%, respectively). In general, GPs, AHPs and consumers are sanguine about the projects, and have reported positive consumer outcomes. However, as with any new initiative, there are some practical and professional issues that need to be addressed. The projects are improving access to evidence-based, non-pharmacological therapies. The continuation and expansion of the initiative should be a priority.

Promoting physical activity to older adults: a preliminary evaluation of three general practice-based strategies

The aim of this study was to explore the feasibility of an exercise scientist (ES) working in general practice to promote physical activity (PA) to 55 to 70 year old adults. Participants were randomised into one of three groups: either brief verbal and written advice from a general practitioner (GP) (G1, N=9); or individualised counselling and follow-up telephone calls from an ES, either with (G3, N=8) or without a pedometer (G2, N=11). PA levels were assessed at week 1, after the 12-wk intervention and again at 24 weeks. After the 12-wk intervention, the average increase in PA was 116 (SD=237) min/wk; N=28, p < 0.001. Although there were no statistically significant between-group differences, the average increases in PA among G2 and G3 participants were 195 (SD=207) and 138 (SD=315) min/wk respectively, compared with no change (0.36, SD=157) in G1. After 24 weeks, average PA levels remained 56 (SD=129) min/wk higher than in week 1. The small numbers of participants in this feasibility study limit the power to detect significant differences between groups, but it would appear that individualised counselling and follow-up contact from an ES, with or without a pedometer, can result in substantial changes in PA levels. A larger study is now planned to confirm these findings.

Quality of diabetes care and coronary heart disease absolute risk in patients with type 2 diabetes mellitus in Australian general practice

Objective: To examine the quality of diabetes care and prevention of cardiovascular disease (CVD) in Australian general practice patients with type 2 diabetes and to investigate its relationship with coronary heart disease absolute risk (CHDAR). Methods: A total of 3286 patient records were extracted from registers of patients with type 2 diabetes held by 16 divisions of general practice (250 practices) across Australia for the year 2002. CHDAR was estimated using the United Kingdom Prospective Diabetes Study algorithm with higher CHDAR set at a 10 year risk of >15%. Multivariate multilevel logistic regression investigated the association between CHDAR and diabetes care. Results: 47.9% of diabetic patient records had glycosylated haemoglobin (HbA1c) >7%, 87.6% had total cholesterol >= 4.0 mmol/l, and 73.8% had blood pressure (BP) >= 130/85 mm Hg. 57.6% of patients were at a higher CHDAR, 76.8% of whom were not on lipid modifying medication and 66.2% were not on antihypertensive medication. After adjusting for clustering at the general practice level and age, lipid modifying medication was negatively related to CHDAR (odds ratio (OR) 0.84) and total cholesterol. Antihypertensive medication was positively related to systolic BP but negatively related to CHDAR (OR 0.88). Referral to ophthalmologists/optometrists and attendance at other health professionals were not related to CHDAR. Conclusions: At the time of the study the diabetes and CVD preventive care in Australian general practice was suboptimal, even after a number of national initiatives. The Australian Pharmaceutical Benefits Scheme (PBS) guidelines need to be modified to improve CVD preventive care in patients with type 2 diabetes.

Performance on tests sensitive to impaired executive ability in schizophrenia, mania and well controls: acute and subacute phases

Aims: To compare the performance of schizophrenia, mania and well control groups on tests sensitive to impaired executive ability, and to assess the within-group stability of these measures across the acute and subacute phases of psychoses. Method: Recently admitted patients with schizophrenia (n=36), mania (n=18) and a well control group (n=20) were assessed on two occasions separated by 4 weeks. Tests included: the Controlled Oral Word Association Test, the Stroop Test, the Wisconsin Card Sort Test, and the Trail Making Test. Results: The two patient groups were significantly impaired on the Stroop Test at both time points compared to the control group. Significant group differences were also found for the Trail Making Test at Time 1 and for the Wisconsin Card Sort Test at Time 2. When controlled for practice effect, significant improvements over time were found on the Stroop and Trail Making tests in the schizophrenia group and on WCST Categories Achieved in the mania group. Discussion: Compared to controls, the patient groups were impaired on measures related to executive ability. The pattern of improvement on test scores between the acute and subacute phases differed between patients with schizophrenia versus patients with mania. (C) 1997 Elsevier Science B.V.

Chemical characterization of soils of a tropical humid forest zone: A methodology

A methodology, based on a combination of routinely performed analyses and investigation of fundamental charge and anion sorption properties, was used to characterize the soils of the humid forest zone of Cameroon, In general, the soils have about 2 cmol kg(-1) permanent negative charge, with about 1 cmol kg(-1) from variable-charge sources at current soil pH values, Furthermore, they are impoverished with respect to Ca, Mg, and K, while Al frequently dominates the exchange complex. Thus, the ability of these soils to retain base cations is more limited than is suggested by the cation-exchange capacity (CEC), Therefore we propose the concept of a degradation index (DI) defined as: DI = 100(CEC5.5 - sum of basic cations)/CEC5.5, where CEC5.5 is the CEC measured at pH 5.5, This index encompasses degradation a soil may have experienced from natural or man-made causes, Extractable PO4 concentrations are considered very low and the soils have a moderate to high capacity to fix added PO4. Surface soil SO4 concentrations are considered marginal to deficient for plant growth, though adequate reserves of SO4 are held in the subsoil by SO4 sorption, The approach used demonstrated that the five morphologically different soil profile classes identified in the zone have similar chemical characteristics. Thus, the results of experimentation conducted on one of the soil profile classes will be applicable throughout the zone, Furthermore, the approach has provided a means of identifying comparable soil types in other parts of the world and will guide technology transfer, The analytical methods used in this study are relatively simple and require no specialized equipment, and are therefore within the capabilities of many laboratories in the developing world.

Characterizing QALYs under a general rank dependent utility model

This paper provides a characterization of QALYs, the most important outcome measure in medical decision making, in the context of a general rank dependent utility model. We show that both for chronic and for nonchronic health states the characterization of QALYs depends on intuitive conditions. This facilitates the assessment of the validity of QALYs in rank dependent non-expected utility theories and a comparison with other utility based measures of health.

Spatial learning ability of rats following differing levels of exposure to alcohol during early postnatal life

Rats exposed to a relatively high dose (7.5 g/kg body weight) of alcohol on either the fifth or tenth postnatal day of age have been reported to have long-lasting deficits in spatial learning ability as tested on the Morris water maze task. The question arises concerning the level of alcohol required to achieve this effect. Wistar rats were exposed to either 2, 4 or 6 g/kg body weight of ethanol administered as a 10% solution. This ethanol was given over an 8-h period on the fifth postnatal day of age by means of an intragastric cannula. Gastrostomy controls received a 5% sucrose solution substituted isocalorically for the ethanol. Another set of pups raised by their mother were used as suckle controls. All surgical procedures were carried out under halothane vapour anaesthesia. After the artificial feeding regimes all pups were returned to lactating dams and weaned at 21 days of age. The spatial learning ability of these rats was tested in the Morris water maze when they were between 61-64 days of age. This task requires the rats to swim in a pool containing water made opaque and locate and climb onto a submerged platform. The time taken to accomplish this is known as the escape latency. Each rat was subjected to 24 trials over 3 days of the test period. Statistical analysis of the escape latency data revealed that the rats given 6 g/kg body weight of ethanol had significant deficits in their spatial learning ability compared with their control groups. However, there was no significant difference in spatial learning ability for the rats given either 2 or 4 g/kg body weight of ethanol compared with their respective gastrostomy or suckle control animals. We concluded that ethanol exposure greater than 4 g/kg over an 8-h period to 5-day-old rats is required for them to develop long-term deficits in spatial learning behaviour. (C) 1998 Elsevier Science Inc.