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Insight into the evolution of the Tagish Lake carbonaceous chondrite by analysis of the oxygen isotopic composition of extracted water and Mössbauer spectroscopy
Analysis of oxygen isotopes in water from Tagish Lake together with Mössbauer Spectroscopy suggest some similarities to the CI group of meteorites but also suggest differences in the extent of parent body hydrothermal alteration
Perspectives on subnational carbon and climate footprints: A case study of Southampton, UK
Sub-national governments are increasingly interested in local-level climate change management. Carbon- (CO2 and CH4) and climate-footprints—(Kyoto Basket GHGs) (effectively single impact category LCA metrics, for global warming potential) provide an opportunity to develop models to facilitate effective mitigation. Three approaches are available for the footprinting of sub-national communities. Territorial-based approaches, which focus on production emissions within the geo-political boundaries, are useful for highlighting local emission sources but do not reflect the transboundary nature of sub-national community infrastructures. Transboundary approaches, which extend territorial footprints through the inclusion of key cross boundary flows of materials and energy, are more representative of community structures and processes but there are concerns regarding comparability between studies. The third option, consumption-based, considers global GHG emissions that result from final consumption (households, governments, and investment). Using a case study of Southampton, UK, this chapter develops the data and methods required for a sub-national territorial, transboundary, and consumption-based carbon and climate footprints. The results and implication of each footprinting perspective are discussed in the context of emerging international standards. The study clearly shows that the carbon footprint (CO2 and CH4 only) offers a low-cost, low-data, universal metric of anthropogenic GHG emission and subsequent management
Adherence to UK national guidance for discharge information: an audit in primary care
Aims: Poor communication of clinical information between healthcare settings is associated with patient harm. In 2008, the UK National Prescribing Centre (NPC) issued guidance regarding the minimum information to be communicated upon hospital discharge. This study evaluates the extent of adherence to this guidance and identifies predictors of adherence. Methods: This was an audit of discharge summaries received by medical practices in one UK primary care trust of patients hospitalized for 24 h or longer. Each discharge summary was scored against the applicable NPC criteria which were organized into: ‘patient, admission and discharge’, ‘medicine’ and ‘therapy change’ information. Results: Of 3444 discharge summaries audited, 2421 (70.3%) were from two teaching hospitals and 906 (26.3%) from three district hospitals. Unplanned admissions accounted for 2168 (63.0%) of the audit sample and 74.6% (2570) of discharge summaries were electronic. Mean (95% CI) adherence to the total NPC minimum dataset was 71.7% [70.2, 73.2]. Adherence to patient, admission and discharge information was 77.3% (95% CI 77.0, 77.7), 67.2% (95% CI 66.3, 68.2) for medicine information and 48.9% (95% CI 47.5, 50.3) for therapy change information. Allergy status, co-morbidities, medication history and rationale for therapy change were the most frequent omissions. Predictors of adherence included quality of the discharge template, electronic discharge summaries and smaller numbers of prescribed medicines. Conclusions: Despite clear guidance regarding the content of discharge information, omissions are frequent. Adherence to the NPC minimum dataset might be improved by using comprehensive electronic discharge templates and implementation of effective medicines reconciliation at both sides of the health interface
Impact of concrete on riparian ecosystems
Throughout the world, concrete is used extensively in urban development. Due to its convenience and durability, most paths, carparks, dams, and even drainage systems are constructed from concrete. However, recent studies indicate that concrete significantly affects water chemistry and that concrete infrastructure may have a major effect on the chemistry of nearby streams. This is particularly relevant for sensitive waterways such as those in the Blue Mountains region in Sydney, Australia. This study aimed to investigate the chemical changes associated with concrete exposure by conducting water recirculation experiments. Water collected from a pristine Blue Mountains Upland Swamp (BMUS) was mildly acidic (average pH of 4.65) with a low electrical conductivity (EC of 57.99μS/cm) before concrete exposure. After the water was continuously recirculated through a concrete pipe for 120 minutes, pH and EC increased significantly, to 7.87 and 137.72μS/cm respectively. Significant increases in concentrations of ions such as bicarbonate, calcium and sulphate were also observed. Results verify previous findings that concrete significantly and rapidly affects water chemistry and support the hypothesis that concrete plays a significant role in the chemical differences seen between urban and non-urban waterways. Results also indicate that concrete is a source of metals such as copper, chromium, strontium, titanium, and lithium. Furthermore, this study aimed to investigate whether these metals have the potential to affect ecosystems more broadly. Salix babylonica, a common invasive plant species in the Sydney region, was grown in pristine BMUS water and concrete-recirculated BMUS water. Plants grown in concrete-recirculated water had significantly greater new growth and the tissue of these plants was significantly higher in concentrations of barium, copper, lead, manganese, and strontium. As metals in the water appear to be moving into plant tissue, results suggest that these metals are bioavailable and thus have the potential to move into higher trophic levels and the ecosystem more generally. Further investigation is required to determine how far these metals may permeate the food chain
Carbon and nitrogen isotope ratios in meteoritic organic matter: indicators of alteration processes on the parent asteroid
Macromolecular organic materials in chondrites display significant variations in carbon and nitrogen stable isotopes. In recent years, these variations have been interpreted as a record of aqueous and thermal processing on asteroids shortly after the birth of the Solar System. In this paper we review and summarize the key data and main interpretative approaches related to this study area. Armed with these methods we attempt to reinterpret the whole rock chondrite data set in the literature
Places to Swim: Perspectives Report
People love to recreate around, on and in the water. As part of the Department of Planning and Open Spaces Program, Places to Swim provides an opportunity to improve access to natural waterways for recreation across NSW. This report investigates the issues, barriers and benefits associated with opening waterways for recreation. NSW is enriched with a range of beautiful and healthy waterways providing opportunities for people to swim and recreate safely, create places that people can visit, and help build better communities. A key attribute for all swimming sites is ensuring they are safe to use. Recreation involving waterways inherently involves risks, including exposure to waterborne contaminants and the risk of injury and drowning. As new swimming sites are opened the risks need to be identified, monitored, and managed
Plasma Leak From the Circulation Contributes to Poor Outcomes for Preterm Infants: A Working Hypothesis
Preterm infants are at high risk of death and disability resulting from brain injury. Impaired cardiovascular function leading to poor cerebral oxygenation is a significant contributor to these adverse outcomes, but current therapeutic approaches have failed to improve outcome. We have re-examined existing evidence regarding hypovolemia and have concluded that in the preterm infant loss of plasma from the circulation results in hypovolemia; and that this is a significant driver of cardiovascular instability and thus poor cerebral oxygenation. High capillary permeability, altered hydrostatic and oncotic pressure gradients, and reduced lymphatic return all combine to increase net loss of plasma from the circulation at the capillary. Evidence is presented that early hypovolemia occurs in preterm infants, and that capillary permeability and pressure gradients all change in a way that promotes rapid plasma loss at the capillary. Impaired lymph flow, inflammation and some current treatment strategies may further exacerbate this plasma loss. A framework for testing this hypothesis is presented. Understanding these mechanisms opens the way to novel treatment strategies to support cardiovascular function and cerebral oxygenation, to replace current therapies, which have been shown not to change outcomes
Interactions of the Gasotransmitters Contribute to Microvascular Tone (Dys)regulation in the Preterm Neonate
Background & Aims
Hydrogen sulphide (H2S), nitric oxide (NO), and carbon monoxide (CO) are involved in transitional microvascular tone dysregulation in the preterm infant; however there is conflicting evidence on the interaction of these gasotransmitters, and their overall contribution to the microcirculation in newborns is not known. The aim of this study was to measure the levels of all 3 gasotransmitters, characterise their interrelationships and elucidate their combined effects on microvascular blood flow.
Methods
90 preterm neonates were studied at 24h postnatal age. Microvascular studies were performed by laser Doppler. Arterial COHb levels (a measure of CO) were determined through co-oximetry. NO was measured as nitrate and nitrite in urine. H2S was measured as thiosulphate by liquid chromatography. Relationships between levels of the gasotransmitters and microvascular blood flow were assessed through partial correlation controlling for the influence of gestational age. Structural equation modelling was used to examine the combination of these effects on microvascular blood flow and derive a theoretical model of their interactions.
Results
No relationship was observed between NO and CO (p = 0.18, r = 0.18). A positive relationship between NO and H2S (p = 0.008, r = 0.28) and an inverse relationship between CO and H2S (p = 0.01, r = -0.33) exists. Structural equation modelling was used to examine the combination of these effects on microvascular blood flow. The model with the best fit is presented.
Conclusions
The relationships between NO and H2S, and CO and H2S may be of importance in the preterm newborn, particularly as NO levels in males are associated with higher H2S levels and higher microvascular blood flow and CO in females appears to convey protection against vascular dysregulation. Here we present a theoretical model of these interactions and their overall effects on microvascular flow in the preterm newborn, upon which future mechanistic studies may be based.The authors would like to acknowledge the parents of the neonates enrolled in the 2CANS
study for their participation, the staff of the Kaleidoscope Neonatal Intensive Care Unit at the
John Hunter Children’s Hospital, and Kimberly-Clark Australia for providing the diapers used
in this stud
Geochemical impact of urban development on fragile freshwater wetlands
Urbanization is associated with increased cover of impervious surfaces, which poses significant challenges to freshwater ecosystems globally. Implications of catchment urbanization include altered natural hydrology, erosion, weed invasions and modified water chemistry. Blue Mountains Upland Swamps are sensitive freshwater ecosystems located in the Blue Mountains region in south-eastern Australia. They have high conservation value as they are located within a World Heritage Area, are a listed 'endangered ecological community' in Australia and contain endemic and endangered flora and fauna. Water chemistry was assessed in four naturally vegetated and four urban swamps. Urban swamps had higher impervious cover and modified water chemistry, with elevated pH, electrical conductivity and major ions compared to non-urban swamps. Water in urban swamps had elevated calcium, potassium and bicarbonate compared to non-urban catchments, by 19.8, 5.2 and 10.3 times respectively. Although further research is needed, we hypothesize that common concrete materials, particularly drainage infrastructure, strongly influenced differences between urban and nonurban catchments. This adds to growing international research highlighting the potential role of concrete in modifying urban water chemistry due to gradual dissolution and mobilization of ions. In an increasingly urban world, consideration of the ecological consequences of urbanization is required to guide future management approaches
Signatures of urbanization in Temperate Highland Peat Swamps on Sandstone (THPSS) of the Blue Mountains World Heritage Area
Urban freshwater ecosystems exhibit distinct patterns of elevated major ions (calcium, potassium and bicarbonate) and metals, referred to as the ‘urban geochemical signature’. However, the implications of this urban fingerprint at the water-sediment interface within sensitive freshwater systems are not well-known. Temperate Highland Peat Swamps on Sandstone are unique freshwater wetlands found within and surrounding the high-conservation value Greater Blue Mountains World Heritage Area and are a listed ‘endangered ecological community’ in Australia. Water and sediment chemistry were assessed within four urban and four naturally vegetated swamp catchments, through field monitoring and novel laboratory techniques (including X-ray diffraction). Urban swamps had distinct elemental signatures compared to naturally vegetated swamps. Urban swamp water displayed increased pH, elevated ionic strength, major ions (calcium and bicarbonate) and metals (strontium, barium, manganese and iron). Urban swamp sediment had higher calcium, with calcium hydroxide detected at two urban sites. Urban development and concrete drainage infrastructure in swamp catchments modify natural hydrology and water chemistry. Findings suggest swamp sediments may act as sinks of metals and alkalinity, with urbanization remaining a potential source. However, the consequences for high-conservation value systems are not well understood. As urbanization continues to expand, this has implications for fragile freshwater environments worldwide
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