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This is the first projection of marine circulation and biogeochemistry for the Ascension Island Marine Protected Area (AIMPA). Marine Protected Areas are a key management tool used to safeguard biodiversity, but their efficacy is increasingly threatened by climate change. To assess an MPA's vulnerability to climate change and predict biological responses, we must first project how the local marine environment will change. We present the projections of an ensemble from the Sixth Coupled Model Intercomparision Project. Relative to the recent past (2000–2010), the multi‐model means of the mid‐century (2040–2050) project that the AIMPA will become warmer (+0.9 to +1.2°C), more saline (+0.01 to +0.10), with a shallower mixed layer depth (−1.3 to −0.8 m), a weaker Atlantic Equatorial Undercurrent (AEU) (−1.5 to −0.4 Sv), more acidic (−0.10 to −0.07), with lower surface nutrient concentrations (−0.023 to −0.0141 mmol N m−3 and −0.013 to −0.009 mmol P m−3), less chlorophyll (−6 to −3 µg m−3) and less primary production (−0.31 to −0.20 mol m−2 yr−1). These changes are often more extreme in the scenarios with higher greenhouse gases emissions and more significant climate change. Using the multi‐model mean for two scenarios in the years 2090–2100, we assessed how five key ecosystem services in both the shallow subtidal and the pelagic zone were likely to be impacted by climate change. Both low and high emission scenarios project significant changes to the AIMPA, and it is likely that the provision of several ecosystem services will be negatively impacted. Plain Language Summary: Ascension Island is a small remote volcanic island in the equatorial Atlantic Ocean. The seas around Ascension Island have been protected from commercial fishing since 2019. We used the marine component of computer simulations of the Earth's climate to try to understand the future of the Ascension Island Marine Protected Area (AIMPA). Over the next century, the AIMPA region will become warmer, more saline, more acidic, less productive, and with lower nutrient and chlorophyll concentrations in the surface waters. The most important current of the region, the Atlantic Equatorial Current, is also projected to weaken in all scenarios. These changes are likely to negatively impact the ability of the AIMPA to provide ecosystem services such as healthy ecosystems, fish stocks, the removal of carbon dioxide from the air, and attract tourism. This work is important because it is the first projection of the climate around the AIMPA since it was created, and it has allowed local policymakers to understand how the changing climate is likely to affect their environment and ecosystem services. Key Points: We present the first projection of the future marine circulation and biogeochemistry of the Ascension Island Marine Protected Area (AIMPA)The AIMPA will become warmer, more saline, more acidic, with less surface nutrients, primary production and chlorophyllThe AIMPA's capacity to provide ecosystem services will be significantly negatively impacted under a high emission scenario [ABSTRACT FROM AUTHOR]

Prader-Willi syndrome (PWS) is a genetic disorder characterized by hyperphagia and food preoccupations. Researchers indicate that individuals with PWS, including young children, exhibit food and non-food-related compulsions. Normative rituals are also often present among typically developing preschoolers. However, it is unclear how these behaviors affect the child. Although preschoolers with PWS exhibit more "types" of rituals than other populations, it is uncertain if the "severity" of these behaviors differs from the rituals experienced during normative development. Thus, the purpose of this research was to determine whether the ritualistic behaviors exhibited by preschoolers with PWS differ in severity from those exhibited during normative development. We also sought to identify whether non-food ritualistic behavior was related to the hyperphagia in PWS. Parents of 68 children with PWS, 86 typically developing children, and 57 children with developmental delays completed questionnaires on rituals and eating behavior. Children with PWS exhibited more severe ritualistic behavior than typically developing children but not other children with developmental delays. However, the severity of non-food-related rituals was related to the severity of eating behavior in PWS. We hypothesize that this link between hyperphagia and non-food-related compulsivity may share a common underlying neurobiological mechanism.

Summary: A 12‐year‐old Tennessee Walking Horse mare displaying signs of severe colic for 48 h was found during an exploratory celiotomy to have entrapment of a cranially displaced large colon and the caecum through a rent in the mesoduodenum. The entrapment was relieved, and 24 h later, the mesoduodenal rent was closed laparoscopically, with the mare standing. The owner reported 6 months later that the mare had displayed no signs of colic since being discharged from the hospital 11 days after surgery. [ABSTRACT FROM AUTHOR]

The mid-Holocene eruption of Aniakchak volcano (Aniakchak II) in southwest Alaska was among the largest eruptions globally in the last 10,000years (VEI-6). Despite evidence for possible impacts on global climate, the precise age of the eruption is not well-constrained and little is known about regional environmental impacts. A closely spaced sequence of radiocarbon dates at a peatland site over 1000km from the volcano show that peat accumulation was greatly reduced with a hiatus of approximately 90-120yr following tephra deposition. During this inferred hiatus no paleoenvironmental data are available but once vegetation returned the flora changed from a Cyperaceae-dominated assemblage to a Poaceae-dominated vegetation cover, suggesting a drier and/or more nutrient-rich ecosystem. Oribatid mites are extremely abundant in the peat at the depth of the ash, and show a longer-term, increasingly wet peat surface across the tephra layer. The radiocarbon sample immediately below the tephra gave a date of 1636-1446cal yr BC suggesting that the eruption might be younger than previously thought. Our findings suggest that the eruption may have led to a widespread reduction in peatland carbon sequestration and that the impacts on ecosystem functioning were profound and long-lasting. [ABSTRACT FROM AUTHOR]

Snow in the environment acts as a host to rich chemistry and provides a matrix for physical exchange of contaminants within the ecosystem. The goal of this review is to summarise the current state of knowledge of physical processes and chemical reactivity in surface snow with relevance to polar regions. It focuses on a description of impurities in distinct compartments present in surface snow, such as snow crystals, grain boundaries, crystal surfaces, and liquid parts. It emphasises the microscopic description of the ice surface and its link with the environment. Distinct differences between the disordered air-ice interface, often termed quasi-liquid layer, and a liquid phase are highlighted. The reactivity in these different compartments of surface snow is discussed using many experimental studies, simulations, and selected snow models from the molecular to the macro-scale. Although new experimental techniques have extended our knowledge of the surface properties of ice and their impact on some single reactions and processes, others occurring on, at or within snow grains remain unquantified. The presence of liquid or liquid-like compartments either due to the formation of brine or disorder at surfaces of snow crystals below the freezing point may strongly modify reaction rates. Therefore, future experiments should include a detailed characterisation of the surface properties of the ice matrices. A further point that remains largely unresolved is the distribution of impurities between the different domains of the condensed phase inside the snowpack, i.e. in the bulk solid, in liquid at the surface or trapped in confined pockets within or between grains, or at the surface. While surface-sensitive laboratory techniques may in the future help to resolve this point for equilibrium conditions, additional uncertainty for the environmental snowpack may be caused by the highly dynamic nature of the snowpack due to the fast metamorphism occurring under certain environmental conditions. Due to these gaps in knowledge the first snow chemistry models have attempted to reproduce certain processes like the long-term incorporation of volatile compounds in snow and firn or the release of reactive species from the snowpack. Although so far none of the models offers a coupled approach of physical and chemical processes or a detailed representation of the different compartments, they have successfully been used to reproduce some field experiments. A fully coupled snow chemistry and physics model remains to be developed. [ABSTRACT FROM AUTHOR]

Coccolithophores are the primary oceanic phyto-plankton responsible for the production of calcium carbonate (CaCO3). These climatically important plankton play a key role in the oceanic carbon cycle as a major contributor of carbon to the open ocean carbonate pump (~50%) and their calcification can affect the atmosphere-to-ocean (air-sea) uptake of carbon dioxide (CO2) through increasing the seawater partial pressure of CO2 (pCO2). Here we document variations in the areal extent of surface blooms of the globally important coccolithophore, Emiliania hux-leyi, in the North Atlantic over a 10-year period (1998-2007), using Earth observation data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS). We calculate the annual mean sea surface areal coverage of E. huxleyi in the North Atlantic to be 474 000 ± 104 000 km², which results in a net CaCO3 carbon (CaCO3-C) production of 0.14-1.71TgCaCO3-C per year. However, this surface coverage (and, thus, net production) can fluctuate inter-annually by -54/+81 % about the mean value and is strongly correlated with the El Nino/Southern Oscillation (ENSO) climate oscillation index (r = 0.75, p<0.02). Our analysis evaluates the spatial extent over which the E. huxleyi blooms in the North Atlantic can increase the pCO2 and, thus, decrease the localised air-sea flux of atmospheric CO2. In regions where the blooms are prevalent, the average reduction in the monthly air-sea CO2 flux can reach 55 %. The maximum reduction of the monthly air-sea CO2 flux in the time series is 155 %. This work suggests that the high variability, frequency and distribution of these calcifying plankton and their impact on pCO2 should be considered if we are to fully understand the variability of the North Atlantic air-to-sea flux of CO2. We estimate that these blooms can reduce the annual N. Atlantic net sink atmospheric CO2 by between 3-28 %. [ABSTRACT FROM AUTHOR]

Ice and snow in the environment are important because they not only act as a host to rich chemistry but also provide a matrix for physical exchanges of contaminants within the ecosystem. This review discusses how the structure of snow influences both chemical reactivity and physical processes, which thereby makes snow a unique medium for study. The focus is placed on impacts of the presence of liquid and surface disorder using many experimental studies, simulations, and field observations from the molecular to the micro-scale. [ABSTRACT FROM AUTHOR]

Coccolithophores are the primary oceanic phytoplankton responsible for the production of calcium carbonate (CaCO3). These climatically important plankton play a key role in the oceanic carbon cycle as a major contributor of carbon to the open ocean carbonate pump (~50 %) and their formation can affect the atmosphere-to-ocean (air- sea) uptake of carbon dioxide (CO2) through increasing the seawater partial pressure of CO2 (pCO2). Here we document variations in the areal extent of surface blooms of the globally important coccolithophore, Emiliania huxleyi, in the North Atlantic over a 10-year period (1998-2007), using Earth observation data from the Sea-viewing Wide Field of view Sensor (SeaWiFS).We calculate the annual mean surface areal coverage of E. huxleyi in the North Atlantic to be 474 000±119 000 km² yr-1, which results in a net CaCO3 production of 0.62±0.15 Tg CaCO3 carbon per year. However, this surface coverage and net production can fluctuate by -54/+81% about these mean values and are strongly correlated with the El Niño/Southern Oscillation (ENSO) climate oscillation index (r =0.75, p<0.02). Our analysis evaluates the spatial extent over which the E. huxleyi blooms in the North Atlantic can increase the pCO2 and thus decrease the localised sink of atmospheric CO2. In regions where the blooms are prevalent, the average reduction in the monthly CO2 sink can reach 12 %. The maximum reduction of the monthly CO2 sink in the time series is 32 %. This work suggests that the high variability, frequency and distribution of these calcifying plankton and their impact on pCO2 should be considered within modelling studies of the North Atlantic if we are to fully understand the variability of its air-to-sea CO2 flux. [ABSTRACT FROM AUTHOR]

If carbon capture and storage is to be adopted as a CO2 mitigation strategy, it is important to understand the associated risks. The risk analysis consists of several elements such as leakage probability, assessing the strength of environmental perturbation, and quantifying the ecological, economic, and social impacts. Here, the environmental perturbation aspect is addressed by using a marine system model of the North West European Shelf seas to simulate the consequences of CO2 additions such as those that could arise from a failure of geological sequestration schemes. Little information exists to guide the choice of leak scenario and many assumptions are required; for consistency the assumptions err towards greater impact and what would be in likelihood extreme scenarios. The simulations indicate that only the largest leakage scenarios tested are capable of producing perturbations that are likely to have environmental consequences beyond the locality of a leak event. It is shown that, given the available evidence, the chemical perturbation of a sequestration leak, regionally integrated, is likely to be insignificant when compared with that from continued non-mitigated atmospheric CO2 emissions and the subsequent acidification of the marine system. The potential ecological impacts of a large environmental CO2 perturbation are reviewed, indicating that the biogeochemical functioning and biodiversity are sensitive. The key unknowns that must be addressed in future research are identified; namely, the fine scale dispersion of CO2 and the ability of ecological systems to recover from perturbation. [ABSTRACT FROM AUTHOR]

Peatland records of Holocene palaeoclimate have been widely used in Europe. Their potential in western North America remains largely unexploited despite an abundance of candidate sites. Peat humification analysis is a widely used technique for palaeoclimatic inference from peatlands. This study attempts to demonstrate a climatic role in determining peat humification by comparing low-resolution peat humification records from five mires in south-east Alaska. Humification was determined by alkali extraction and colorimetry and records dated by radiocarbon and tephrochronology. Testate amoebae analysis was carried out across a major humification-inferred wet shift in three of the sites. The humification results show variability down the length of the cores but there is only limited agreement between records from different sites. Many general trends in the data appear to be out of phase and periods of proxy 'complacency' are shown. This study does not provide strong evidence for climatic forcing of humification in these sites. Methodological issues including possible problems with the age-depth models and the role of a peat-forming plant species signal in the humification data are discussed. The results support previous studies in suggesting the value of employing a multi-proxy, multi-site, and possibly multi-core approach in peat-based palaeoclimatology. [ABSTRACT FROM AUTHOR]

A person's right to self-determination in health care is now a fundamental principle of health care provision. As a consequence Advance Care Planning (ACP) is a critical issue in health care including palliative care as it is seen as a way of ensuring a person's right to participate not only in future health care choices but in end of life decision making.To date there have been few reports of successful ACP programs. In 2004 and 2005 a program of advance care planning, known as Respecting Patient Choices was introduced in 17 residential aged care facilities in metropolitan Melbourne, Australia. This program consisted of a system-wide approach that included education for aged care staff; information for residents and families as well as changes to organisational processes to ensure that residents have opportunity for self-determination in their future health care.This paper will report on the lessons learnt from this implementation and identify strategies which foster sustainability of ACP. [ABSTRACT FROM AUTHOR]

Ice particles containing NaCl were made by spraying 0.043 M salt solution into liquid nitrogen. The ice particles were packed into capsules and annealed at -8 °C for 168 h and -25 °C for 20 h. This material can be considered as a model material for sintered snow containing impurities. The capsules were fractured open inside the low-temperature scanning electron microscope, which minimized the artefacts caused by cryofixation. The morphology of the sintered structure was observed with low-temperature scanning electron microscope. The microstructure of the sintered material consists of ice grains with a liquid meniscus containing NaCl between the grains. This structure is similar to the equilibrium morphology of water-filled veins in polycrystalline ice and liquid phase sintered metallic materials. The combined effect of the surface energies between the solid, liquid, and vapour governs the morphology of the microstructure. A dihedral angle where the brine intersects a grain boundary in ice of 8.0 ± 2.6°, and a contact angle for brine on ice at the interface with vapour of 5.0 ± 1.3° were measured, for samples quenched from -8 °C. Using the dihedral angle measurement, a surface energy value for ice-brine of 32.6 ± 0.1 mJ/m2 was calculated. [ABSTRACT FROM AUTHOR]

The authors of this article discuss the effects of shame and stigma on female caregivers of people living with AIDS in southern Thailand. They conducted a longitudinal ethnographic case study over 8 months and collected data using interviews, observations, field notes, and journaling. The authors performed qualitative content analysis and narrative analysis. Public judgment was created in a moral climate, framed by Buddhist precepts of correct and honorable behavior, with different levels of tolerance and stigmatization between men and women. Women caregivers engaged in concealing practices, deception, and withdrawal from social relationships to manage the effects of shame and stigma. [ABSTRACT FROM AUTHOR]

In the sport of curling, players sweep the ice in the front of curling stones to increase the distance that the projectiles slide. Their vigorous sweeping raises the surface temperature of the ice, thereby reducing its coefficient of friction. The change in ice temperature is dependent on the velocity that curlers sweep the ice, the downward force they apply, and the pattern that is swept. The forces and velocities applied by Olympic level curlers were recorded with an instrumented brush. Laboratory-based rubbing experiments were conducted to determine the temperature rise in ice from sweeping. A numerical model was developed on the basis of the recorded sweeping profiles and laboratory-based rubbing experiments. The model was used to compare the thermal effects of two popular sweeping styles and shows that a conventional low attack angle style is the most efficient. [ABSTRACT FROM AUTHOR]

The design and manufacture of an instrumented curling brush, sweep ergometer, has provided the first quantitative analysis of sweeping in the Olympic sport of curling. Sweeping is a method by which curlers alter the trajectory of curling stones and can provide the difference between winning and losing in a target-based sport where centimetre scale variations are vitally important. Two design phases led to the development of the wireless sweep ergometer that is able to measure an athlete's performance unencumbered. The ergometer measures the vertical and horizontal forces, and acceleration of the brush head in two axes. Graphical output can be used to analyse player technique, strength, and rate of fatigue. The ergometer provides an outstanding tool for both skill and consistency coaching and will help in team selection and match tactics. [ABSTRACT FROM AUTHOR]

Recently, it has been shown that the tire-ice friction is characterized by a significant dynamic potential for abrupt increases of wheel torque. With the aim to gain insight into the dynamic tire friction potential features and to provide a comprehensive set of experimental data for model validation, a detailed experimental investigation of the dynamic potential has been presented in this article. The experimental data have been collected by using an experimental electrical vehicle with an in-wheel motor. Influence of the following operating parameters has been analyzed: rate of change of applied wheel torque, time for which the tire stands still on ice before applying the abrupt transient, initial vehicle speed, and initial tire force. In order to check a possible correlation between the dynamic potential and the rubber-ice friction dynamics, an experimental analysis based on a pin-on-disc tribometer has also been presented. [ABSTRACT FROM AUTHOR]

This paper reports on the management of family centered palliative care in different aged care and acute Australian inpatient settings, following the integration of palliative care with mainstream services. Eighty-eight semistructured interviews were conducted and 425 questionnaires (Palliative Care Practices Questionnaire--PCPQ) were returned, completed from 12 regional and metropolitan locations. Transcribed interviews were analyzed using QSR NVivo and mean PCPQ scores from the four settings were compared. Scores on items from the PCPQ related to family centered care confirmed the analyses. Interviews revealed that factors contributing to the level of support for families offered in the various settings included the core business of the unit; the length of stay of the patients or residents; the acuity or symptom burden; and the coordinated involvement of the multidisciplinary team. Strategies for improving supportive family care are proposed. [ABSTRACT FROM AUTHOR]

To present radiocarbon dated early Holocene pollen analytical data from two sites on the northern plain of the Isle of Man and to discuss the implications of the vegetation history in relation to severance of the island from the British Isles and to identify further evidence for divergent biogeographical development previously exemplified by the survival and apparent dwarfism of late glacial Megaloceros giganteus (Giant Deer). The Isle of Man, British Isles. Pollen analysis and AMS radiocarbon dating of late glacial to early Holocene lake sequences at Pollies and Curragh-y-Cowle on the northern plain of the Isle of Man. The pollen data indicate a prolonged period of pre-woodland vegetation after the late Glacial/Holocene transition, which lasted for most of the first post-glacial millennium. This persistence of pre-forest environments meant that the expansion of Betula woodland occurred later in this part of the Isle of Man than in adjacent areas of Britain and Ireland. The Isle of Man, in the northern Irish Sea, was isolated from Britain during the late Glacial period perhaps explaining the delayed arrival of tree species. Delayed rise of the Holocene forest compared with surrounding regions probably reflects severance of the land-bridge with Cumbria, but also could be a function of climate changes during the early Holocene and local environmental conditions. Late survival and the dwarfism of the Megaloceros giganteus (Giant Deer) fauna is another example of biogeographical divergence during the early Holocene/late Glacial of the Isle of Man. The delayed afforestation and absence of human hunters in the Manx early Holocene offers a permissive environmental context for the as yet unproven survival of Megaloceros into the early Holocene. [ABSTRACT FROM AUTHOR]

Drawing on a feminist praxis study in which nurses were asked to explore their experiences in caring for people of culturally and linguistically diverse backgrounds, cultural frameworks bounded by interconnected markers of race, ethnicity and gender were constructed to analyse the nurses' narrative accounts. The aims of this paper are to discuss the analytical framework that draws on black feminist and postcolonial writers used to examine the cultural constructions of nursing practice. It will also draw attention to one of the major findings of the study in which, through this analytical process, broader connections between health and multicultural government policies, institutional structures and the microcosm of nursing practice were exposed. Through this analysis, an exclusionary whitecentric healthcare culture was exposed, which rendered people of non-English speaking background invisible. [ABSTRACT FROM AUTHOR]

The optical properties of polycrystalline copper subjected to tensile stress are monitored in situ and in real time using reflection anisotropy spectroscopy (RAS). It is shown that RAS allows investigation of the plastic regime. Here, in contrast to the Hooke's law regime, the stress-induced RAS lineshape is found to be dependent on the applied stress. The optical anisotropy in the visible region of the electromagnetic spectrum is directly proportional to the mechanical strain. An intense RAS peak observed at a photon energy of 4.0 eV is observed to saturate at a stress approximately equal to the yield stress of copper. This work demonstrates the potential of RAS as a nanomechanics monitor of materials under mechanical stress. [ABSTRACT FROM AUTHOR]

Pollen, charcoal and fungal spore analysis of the base of a radiocarbon-dated peat profile at North Gill, North York Moors, N.E. England, provides detailed evidence for an episode of fire-disturbance of woodland atc . 6300 bp (uncalibrated), within the Late Mesolithic cultural period. As with other similar episodes in the uplands of Britain, the pollen data documents post-disturbance regeneration to woodland through ruderal and grassland herb, heath and successional shrub plant communities. Such seral ecological changes have previously been interpreted as the desired result of deliberate disturbance by Mesolithic foragers, as part of a conscious land-use strategy designed to attract ungulate populations to the disturbed areas and increase hunting efficiency and yield. Fungal spore analyses through the North Gill disturbance phase support the indirect ecological inferences from the pollen and charcoal data, provide the first circumstantial evidence of animal concentration in post-fire disturbed areas during the Late Mesolithic and so test and support the basic ecological premise of the Late Mesolithic fire ecology/land-use model. [Copyright &y& Elsevier]

Much research has been conducted for understanding the health needs of people of different cultural backgrounds and the problems they experience in seeking health care. In Australia, despite such research, it is argued that there remains an exclusionary health care culture that continues to affect equity and access for people of non-English speaking background. There was a need for research in which health professionals examined their own Anglo-Australian culture and its impact on other ethnic communities. Such concerns provided the impetus for a feminist praxis study to engage nurses in understanding and improving care for migrant women. This study was conducted with 26 nurses in a paediatric hospital in Melbourne, Australia. Five collaborative research groups were formed, each consisting of four to six nurses who were co-researchers. Together, the nurses and researchers explored the health care experiences of migrant women, using a variety of quantitative and qualitative data collection strategies. This paper explores a major finding of the study, which was the impact of liberal feminist approaches on the practices of Australian nurses who cared for women of different ethnicity and race. The study found that the efforts of liberal feminist nurses to 'treat all people the same' meant that women from different cultural backgrounds did not always receive equity in care. Through the feminist praxis process the nurses were able to explore contradictions in their practice and focus on equity in care to meet the specific gendered and racially constructed needs of women of different cultural backgrounds. A number of strategies were adopted that included regular use of female health interpreters and provision of privacy for migrant women when caring for their children. [ABSTRACT FROM AUTHOR]

Whilst studies have demonstrated that unicellular phytobenthic organisms can be locally important, little is known of their influence on their ecosystem, especially in terms of modifying benthic trophic dynamics and influencing the coupling between the benthos and pelagos. It may be hypothesized that the controlling influence on microphytobenthos would vary seasonally, with incident light, shading, nutrient depletion and grazing all playing a role. In order to elucidate some of these questions a theoretical model of microphytobenthos has been added to the European Regional Seas Ecosystem Model (ERSEM), coupled to a 1D vertically resolved water column model. Several water columns, extending in depth from 5 to 25 m have been simulated along an offshore transect at approximately 44°18′N. The microphytobenthos are predicted to contribute in excess of 50% of primary production in shallow (<5 m) depths, with light limitation reducing the potential growing season to zero at around 25 m. Light availability is the key factor limiting microphytobenthos, with self-shading dominating this effect in established populations. Grazing is shown to be a significant control on microphytobenthic populations. Nutrient stress is not a major limiting factor of microphytobenthic populations due to the availability of benthic nutrient pools. Although nutrient uptake and cycling via the microphytobenthos is not significant compared with regional inputs, the microphytobenthos significantly impact nutrient regeneration rates, aerobic layer processes and benthic trophic dynamics. Effects on the pelagic ecosystem are minimal. [Copyright &y& Elsevier]

* This paper discusses the findings of a critical study that examined the communication patterns between nurses and general practitioners (GPs) providing palliative care in Australia.* Interviews and focus groups involved 40 palliative care nurses who worked in the three settings of care: community, hospice and hospital.* Issues that impeded effective communication strategies between palliative care nurses and GPs were networking, case management, multiple service providers, lack of standardized documentation and formal tracking of clients, along with difficulties in transmission of relevant practice knowledge.* Supporting strategies for effective formal modes of communicating and reporting are described. [ABSTRACT FROM AUTHOR]

In human rehabilitation medicine, dexamethasone-phosphate is theoretically iontophoresed to localized subcutaneous tissue where conversion to dexamethasone occurs. This delivery system has recently been introduced into veterinary medicine for the same purpose. However, the pharmacokinetic justification for parenteral delivery of this prodrug remains undocumented. Utilizing iontophoretic methods that are relevant to both human and veterinary clinical practice, the present investigation compared injection and iontophoresis of dexamethasone-phosphate into the equine tibiotarsal joint, also known as the tarsocrual joint. The tibiotarsal joints of seven horses were injected with 4 mL of 6 mg/mL dexamethasone-phosphate. With a similar drug concentration and over the same application site, six different horses underwent simultaneous cathodic iontophoresis (4 mA, 40 min) or passive application (0 mA, 40 min) on contralateral limbs. Following all applications, tibiotarsal joint synovium was collected. Local venous blood samples were also collected from the iontophoretic and passive application sites for analysis of plasma drug concentrations. Because of the potential for conversion of dexamethasone-phosphate to dexamethasone, an extraction and analysis protocol was developed for both chemicals. The technique demonstrated a linear range of detection (0.39–12 μg/mL) and a capability for measuring both chemicals in plasma and synovium. Conversion of dexamethasone-phosphate to dexamethasone occurred during synovial incubation (37 °C) and following freeze–thaw cycles. In contrast to the measurable synovial concentrations of dexamethasone-phosphate (2.3±0.96 mg/mL) and dexamethasone (0.27±0.07 mg/mL) following injection, neither drug was detected in the synovium or the local venous blood following iontophoretic or passive applications. In conclusion, these results do not confirm iontophoretic or passive delivery of measurable dexamethasone-phosphate into the tibiotarsal joint using current clinical methods. [ABSTRACT FROM AUTHOR]