586 resultados para Library resources


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With evidence of increasing accident risk due to age-related declines in health and cognition affecting driver performance, there is a need for research promoting safe mobility of older people. The present study aimed to identify transport options and licensing issues for a group of older people in an Australian community. Ninety-five participants aged 75 and over were interviewed about their driving status and accident record and tested for cognitive ability. After stratification on cognitive level and driver status (current, ex-driver or non-driver), 30 were selected for further in-depth interviews concerning demographics, licence status and impact of change, travel options available and used, and travel characteristics. Considerable reliance on the motor vehicle as the mode of transport and the decision to cease driving were major quality-of-life issues. There was little evidence of planning and support in making the decision to stop driving. Some differences in transport decisions on the basis of cognitive level were evident; however, people with severely compromised cognitive ability (and, therefore, unable to give informed consent) had been excluded. The study suggested the need for resources to assist older people/carers/health professionals to plan for the transition from driver to non-driver and to manage alternative transport options more effectively

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Previous studies on tidal water table dynamics in unconfined coastal aquifers have focused on the inland propagation of oceanic tides in the cross-shore direction based on the assumption of a straight coastline. Here, two-dimensional analytical solutions are derived to study the effects of rhythmic coastlines on tidal water table fluctuations. The computational results demonstrate that the alongshore variations of the coastline can affect the water table behavior significantly, especially in areas near the centers of the headland and embayment. With the coastline shape effects ignored, traditional analytical solutions may lead to large errors in predicting coastal water table fluctuations or in estimating the aquifer's properties based on these signals. The conditions under which the coastline shape needs to be considered are derived from the new analytical solution.

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Mixed confined and unconfined groundwater flow occurs in a bounded initially dry aquifer when the hydraulic head at the side boundary suddenly rises above the elevation of the aquifer's top boundary. The flow problem as modelled by the Boussinesq equation is non-trivial because of the involvement of two moving boundaries. The transformed equation (based on a similarity transformation) can, however, be dealt with more easily. Here, we present an approximate analytical solution for this flow problem. The approximate solution is compared with an 'exact' numerical solution and found to be a very accurate description for describing the mixed confined and unconfined flow in the confined aquifer. (C) 2002 Elsevier Science B.V. All rights reserved.

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General practitioners (GPs) deliver the majority of palliative care to patients in the last year of life. This article seeks to examine the nature of GP care, perceptions of the GPs themselves and others of that care, the adequacy of palliative care training, issues relating to accessibility of GPs to palliative care patients, and strategies that may be of use in encouraging more effective delivery of palliative care by GPs. Medline and PubMed databases from 1966 to 2000 were searched, and 135 references identified. Sixty-six of these described studies relevant to GP palliative care. GPs value this part of their work. Most of the time, patients appreciate the contribution the GP makes to palliative care particularly if the GP is accessible, takes time to listen, allows patient and carer to ventilate their feelings, and is seen to be making efforts made regarding symptom relief. However, reports from bereaved relatives suggest that palliative care is performed less well in the community than in other settings. GPs express discomfort about their competence to perform palliative care adequately. They tend to miss symptoms which are not treatable by them, or which are less common. However, with appropriate specialist support and facilities, GPs have been shown to deliver sound and effective care. GP comfort working with specialist teams increases with exposure to this form of patient management, as does the understanding of the potential other team members have in contributing to the care of the patient. Formal arrangements engaging GPs to work with specialist teams have been shown to improve functional outcomes, patient satisfaction, improve effective use of resources and improve effective physician behaviour in other areas of medicine. Efforts by specialist services to develop formal involvement of GPs in the care of individual patients, may be an effective method of improving GP palliative care skills and appreciation of the roles specialist services can play.

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Patients with chronic or complex medical or psychiatric conditions are treated by many practitioners, including general practitioners (GPs). Formal liaison between primary and specialist is often assumed to offer benefits to patients The aim of this study was to assess the efficacy of formal liaison of GPs with specialist service providers on patient health outcomes, by conducting a systematic review of the published literature in MEDLINE, EMBASE, PsychINFO, CINAHL and Cochrane Library databases using the following search terms family physicians': synonyms of 'patient care planning', 'patient discharge' and 'patient care team'; and synonyms of 'randomised controlled trials'. Seven studies were identified, involving 963 subjects and 899 controls. most health outcomes were unchanged, although some physical and functional health outcomes were improved by formal liaison between GPs and specialist services, particularly among chronic mental illness patients. Some health outcomes worsened during the intervention. Patient retention rates within treatment programmes improved with GP involvement, as did patient satisfaction. Doctor (GP and specialist) behaviour changed, with reports of more rational use of resources and diagnostic tests, improved clinical skills, more frequent use of appropriate treatment strategies, and more frequent clinical behaviours designed to detect disease complications Cost effectiveness could not be determined. In conclusion, formal liaison between GPs and specialist services leaves most physical health outcomes unchanged, but improves functional outcomes in chronically mentally ill patients. It may confer modest long-term health benefits through improvements in patient concordance with treatment programmes and more effective clinical practice.

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Dinoflagellates exist in symbiosis with a number of marine invertebrates including giant clams, which are the largest of these symbiotic organisms. The dinoflagellates (Symbiodinium sp.) live intercellularly within tubules in the mantle of the host clam. The transport of inorganic carbon (Ci) from seawater to Symbiodinium (=zooxanthellae) is an essential function of hosts that derive the majority of their respiratory energy from the photosynthate exported by the zooxanthellae. Immunolocalisation studies show that the host has adapted its physiology to acquire, rather than remove CO2, from the haemolymph and clam tissues. Two carbonic anhydrase (CA) isoforms (32 and 70 kDa) play an essential part in this process. These have been localised to the mantle and gill tissues where they catalyse the interconversion of HCO3- to CO2, which then diffuses into the host tissues. The zooxanthellae exhibit a number of strategies to maximise Ci acquisition and utilisation. This is necessary as they express a form II Rubisco that has poor discrimination between CO2 and O-2. Evidence is presented for a carbon concentrating mechanism (CCM) to overcome. this disadvantage. The CCM incorporates the presence of a light-activated CA activity, a capacity to take up both HCO3- and CO2, an ability to accumulate an elevated concentration of Ci within the algal cell, and localisation of Rubisco to the pyrenoid. These algae also express both external and intracellular CAs, with the intracellular isoforms being localised to the thylakoid lumen and pyrenoid. These results have been incorporated into a model that explains the transport of Ci from seawater through the clam to the zooxanthellae.

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The age of sex reversal of the venus tusk fish Choerodon venustus, caught by line fishing at various locations on the southern Great Barrier Reef, indicated that C. venustus is capable of modifying its life cycle in response to increased mortality. The evidence suggests Masthead Reef fish, which experience the highest mortality, underwent sex reversal at a smaller size and younger age than at the other sites. The largest female fish, sexually transitional fish and males were smaller at Masthead Reef than at the Swains Reefs or One Tree Reef at Masthead Reef. There was also considerable overlap in the size of males and females within the exploited populations indicating that sex reversal is not initiated at a particular length but may have a social cause. The sex ratio of fish was essentially the same for fish fully susceptible to line fishing in the Swains and Masthead samples. Circumstantial evidence suggested that the absence of large males in a population may initiate sex reversal, indicating the maintenance of a constant sex ratio may have a social basis. (C) 2002 The Fisheries Society of the British Isles.

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The abundance of coral reefs worldwide is in decline, and despite the ecological importance of reefs, only a limited number of DNA markers have been identified for scleractinian coral genetic studies. This paper addresses the search for new coral molecular markers and investigates the applicability of the cytochrome c oxidase subunit I (COI), the internal transcribed spacer region 1 (ITS1), and the pocilloporin gene to the question of intraspecific variation in the scleractinian coral Pocillopora verrucosa along the southeast African coastline. The COI fragment was 710 bp long and was identical for P. verrucosa (n = 10) and P. damicornis (n = 3). Only two different ITS1 sequences were found (differing by 13 bp insertion), but more importantly, 24% of the sequences were heterogenous indicating that different multiple copies of the sequence exist. Pocilloporin is an intronless gene that was absolutely conserved throughout all P. verrucosa populations (n = 50). Thus, the three DNA regions studied appear unsuitable for the population genetic analyses of P. verrucosa.

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In this study the first measurements of DMSP in six species of corals and ten species of benthic algae collected from four coral reefs in the Great Barrier Reef are reported, together with DMSP measurements made on cultured zooxanthellae. Concentrations ranged from 21 to 3831 (mean=743) fmol DMSP zooxanthellae(-1) in corals, 0.16 to 2.96 nmol DMSP cm(-2) (mean=90) for benthic macroalgae, and 48-285 fmol DMSP zooxanthellae(-1) (mean=153) for cultured zooxanthellae. The highest concentrations of DMSP in corals occurred in Acropora formosa (mean= 371 fmol DMSP zooxanthellae(-1)) and Acropora palifera (mean=3341 fmol DMSP zooxanthellae(-1)) with concentrations in A. palifera the highest DMSP concentrations reported in corals examined to date. As well as inter-specific differences in DMSP, intra-specific variation was also observed. Adjacent colonies of A. formosa that are known to have different thermal bleaching thresholds and morphologically distinct zooxanthellae, were also observed to have different DMSP concentrations, with the zooxanthellae in the colony that bleached containing DMSP at an average concentration of 436 finol zooxanthellae(-1), whilst the non-bleaching colony contained DMSP at an average concentration of 171 finol zooxanthellae(-1). The results of the present study have been used to calculate the area normalized DMSP concentrations in benthic algae (mean=0.015 mmol m(-2)) and corals (mean=2.22 mmol m(-2)) from the GBR. This data indicates that benthic algae and corals are a significant reservoir of DMSP in GBR waters. (C) 2002 Published by Elsevier Science Ltd.

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Sperm ultrastructure is examined in representatives of five genera of the nudibranch gastropod family Chromodorididae: (Chromodoris, Hypselodoris, Glossodoris, Risbecia and Pectenodoris) and the results compared with previous work on other gastropods, especially other nudibranchs. As chromodoridid phylogeny is still incompletely understood, this study partly focuses on the search for new and as yet untapped sources of informative characters. Like spermatozoa of most other heterobranch gastropods, those of the Chromodorididae are elongate, complex cells composed of an acrosomal complex (small, rounded acrosomal vesicle, and columnar acrosomal pedestal), a condensed nucleus, sub-nuclear ring, a highly modified mid-piece (axoneme + coarse fibres surrounded by a glycogen-containing, helically-coiled mitochondrial derivative) and terminally a glycogen piece (or homologue thereof). The finely striated acrosomal pedestal is a synapomorphy of all genera examined here, but interestingly also occurs in at least one dorid (Rostanga arbutus). Substantial and potentially taxonomically informative differences were also observed between genera in the morphology of the nucleus, the neck region of the mid-piece, and also the terminal glycogen piece. The subnuclear ring is shown for the first time to be a segmented, rather than a continuous structure; similarly, the annular complex is shown to consist of two structures, the annulus proper and the herein-termed annular accessory body.