395 research outputs found

    Structure and flow of carbon and nitrogen to the western Irish Sea Nephrops norvegicus fishery: a stable isotope approach.

    Get PDF
    PhDStable isotope analysis was used to describe the structure and flow of organic matter (carbon and nitrogen) from primary production in the water column to the benthos, and into secondary production that supports a fishery for the lobster Nephrops norvegicus in the western Irish Sea. There was strong seasonal variation in the carbon and nitrogen stable isotopes of organic matter associatedw ith the seasonalc ycle of primary production in the surfacew aters. The seasonal isotope signal was used to trace the flow of organic matter from primary production through herbivorous zooplankton to the carnivorous pelagic larvae of Nephrops norvegicus.T he production of larvae represented0 .2 % of spring bloom production. Stable isotope analysis of organic matter throughout the water column was used to track the vertical flux of primary production from the surface to the benthos. The isotope signal was also used to quantify the input of carbon to the benthos, estimated to be 41 % of spring bloom primary production. The carbon input to the benthos supported a simple food chain of three higher trophic levels (TL2 - TL4). Nephrops norvegicus was positioned at TU where it accounted for 96 % of the total biomass at that level. The input of carbon to the benthos was equal to the removal of carbon from the benthos by the Nephrops norvegicus fishery assuming a transfer efficiency of 16 % between each trophic level. Climate warming has caused a decline in primary production in some marine systems. Should similar impacts occur in the western Irish Sea,t he subsequendt ecline in the flux of carbon to the benthos will result in a shortfall in the supply of carbon needed to support the current catch rate of the Nephrops norvegicus fishery.Agri Food and Bioscience Institute (AFBI) formrtly (DARD) in Northern Ireland Natural Environment Research counci

    Environmental economics and valuation: towards a practical investment framework for Catchment Management Authorities in New South Wales

    Get PDF
    The Catchment Management Authorities in New South Wales have programs that are collectively investing $436 million over four years to achieve catchment-wide natural resource/environmental improvements. In this paper, we consider the question of how to best allocate these resources so as to increase the well-being of the public within catchments and the state. We consider the current approaches used by CMAs and make a case for Benefit-Cost Analysis as an alternative means of assessing ex ante questions of priority setting at the catchment level and for project appraisal. A major issue for BCA is the estimation of potential benefits from project investments, particularly the estimation of values that catchment communities and those living outside the catchments place on the non-use benefits associated with environmental improvements. We discuss alternative means of eliciting such values and propose the stated-preference method of Choice Modelling as a means of overcoming this Benefit-Cost Analysis shortcoming, because it incorporates advances in non-market valuation.environmental, economics, choice modelling, non-use values, investment framework, Environmental Economics and Policy,

    Simulation of Lablab Pastures

    Get PDF
    The potential of legume-based pastures to address declining soil nitrogen on marginal cropping soils is increasingly recognised in northern Australia, as such there is a need for cost benefit analysis of pastures and crops in a mixed farming system. In highly variable rainfall environments, biophysical modelling may be the best way of identifying and quantifying interactions with mixed crop-livestock systems on a seasonal basis. This paper describes a case study where both animal productivity and lablab pasture production is simulated. Lablab (Lablab purpureus) is an annual tropical legume widely used as a short-term legume phase in crop-pasture rotations, providing high quality forage for animal production and a low risk nitrogen input for crop production

    Intercalative Stacking: A Critical Feature of DNA Charge-Transport Electrochemistry

    Get PDF
    In electrochemistry experiments on DNA-modified electrodes, features of the redox probe that determine efficient charge transport through DNA-modified surfaces have been explored using methylene blue (MB^+) and Ru(NH_3)_6^(3+) as DNA-binding redox probes. The electrochemistry of these molecules is studied as a function of ionic strength to determine the necessity of tight binding to DNA and the number of electrons involved in the redox reaction; on the DNA surface, MB^+ displays 2e^-/1H^+ electrochemistry (pH 7) and Ru(NH^3)_6^(3+) displays 1e^- electrochemistry. We examine also the effect of electrode surface passivation and the effect of the mode (intercalation or electrostatic) of MB^+ and Ru(NH_3)_6^(3+) binding to DNA to highlight the importance of intercalation for reduction by a DNA-mediated charge-transport pathway. Furthermore, in experiments in which MB^+ is covalently linked to the DNA through a σ-bonded tether and the ionic strength is varied, it is demonstrated that intercalative stacking rather than covalent σ-bonding is essential for efficient reduction of MB^+. The results presented here therefore establish that efficient charge transport to the DNA-binding moiety in DNA films requires intercalative stacking and is mediated by the DNA base pair array

    Anticholinergic Exposure During Rehabilitation: Cognitive and Physical Function Outcomes in Patients with Delirium Superimposed on Dementia

    Get PDF
    OBJECTIVES: We examined the association between anticholinergic medication exposure and subsequent cognitive and physical function in patients with delirium superimposed on dementia during rehabilitation. We also examined length of stay and discharge disposition by anticholinergic medication exposure. DESIGN: In this secondary analysis we used control group data from an ongoing randomized clinical trial. SETTING/PARTICIPANTS: Participants with delirium and dementia were enrolled at admission to post-acute care. These 99 participants had a mean age of 86.11 (±6.83) years; 67.6% were women; 98% were Caucasian; and 33% were positive for at least one APOE e4 allele. MEASURES: We obtained daily measures of cognitive and physical function using: Digit Span; memory, orientation and attention items from the Montreal Cognitive Assessment; CLOX; the Confusion Assessment Method; and the Barthel Index. Anticholinergic medication exposure was measured weekly using the Anticholinergic Cognitive Burden Scale. RESULTS: Using multilevel models for time we found that greater use of clinically relevant anticholinergic medications in the previous week reduced cognitive and physical function, as measured by Digit Span Backwards and the Barthel index, in the current week. There was no effect of anticholinergic medication use on delirium severity, and APOE status did not moderate any outcomes. Greater use of clinically relevant anticholinergic medications was related to longer length of stay but not discharge disposition. CONCLUSIONS: For vulnerable older adults, anticholinergic exposure represents a potentially modifiable risk factor for poor attention, working memory, physical function, and greater length of stay during rehabilitation

    Educators\u27 perspectives about how older hospital patients can engage in a falls prevention education programme: a qualitative process evaluation

    Get PDF
    Objectives: Falls are the most frequent adverse event reported in hospitals. Patient and staff education delivered by trained educators significantly reduced falls and injurious falls in an older rehabilitation population. The purpose of the study was to explore the educators’ perspectives of delivering the education and to conceptualise how the programme worked to prevent falls among older patients who received the education. Design: A qualitative exploratory study. Methods: Data were gathered from three sources: conducting a focus group and an interview (n=10 educators), written educator notes and reflective researcher field notes based on interactions with the educators during the primary study. The educators delivered the programme on eight rehabilitation wards for periods of between 10 and 40 weeks. They provided older patients with individualised education to engage in falls prevention and provided staff with education to support patient actions. Data were thematically analysed and presented using a conceptual framework. Results: Falls prevention education led to mutual understanding between staff and patients which assisted patients to engage in falls prevention behaviours. Mutual understanding was derived from the following observations: the educators perceived that they could facilitate an effective three-way interaction between staff actions, patient actions and the ward environment which led to behaviour change on the wards. This included engaging with staff and patients, and assisting them to reconcile differing perspectives about falls prevention behaviours. Conclusions: Individualised falls prevention education effectively provides patients who receive it with the capability and motivation to develop and undertake behavioural strategies that reduce their falls, if supported by staff and the ward environment

    OXA-48-like carbapenemases in the UK: an analysis of isolates and cases from 2007 to 2014

    Get PDF
    Objectives: OXA-48-like carbapenemases have spread worldwide since 2001. We analysed patient and microbiological data for UK isolates with these enzymes as confirmed by the national reference laboratory from November 2007 - December 2014.  Methods: MICs were determined using BSAC agar dilution. Isolates with reduced susceptibility or resistance to at least one carbapenem and high-level resistance to both piperacillin/tazobactam (MIC ≥ 64 mg/L) and temocillin (MICs ≥ 128 mg/L) were screened by PCR for blaOXA-48-like genes. The genomes of around half of the isolates were sequenced, with MLST types, resistance genes and plasmid replicon types inferred. Patient data provided by sending laboratories were reviewed.  Results: Isolates (n=741) with OXA-48-like carbapenemases were submitted from 111 UK laboratories, representing 536 patients. Almost all (99%; 736/741) were Enterobacteriaceae, predominantly Klebsiella pneumoniae (55%; 408), and most (80%; 595) were from inpatients. WGS of 351 non-duplicate isolates identified blaOXA-48 as the most common variant, found in two-thirds (235/351) of isolates, followed by blaOXA-181 (68), blaOXA-232 (32), blaOXA-244 (10), blaOXA-484 (5) and blaOXA-245 (1). Among K. pneumoniae (163/351), E.coli (114/351), and E. cloacae (42/351), 119 STs were identified. Mapping analyses revealed that 63% (222/351) of isolates harboured plasmids that shared >99% identity to one of four known plasmids; pOXA-48a (44%; 154/351), pOXA-232 (10%; 34/351), pOXA181 (9%; 30/351), and pKP3-A (1%; 4/351); the remaining 37% of isolates harboured blaOXA-48-like in unknown environments.  Conclusions: OXA-48-like carbapenemases are an increasing problem in the UK. This study highlights both the role of successful plasmids and polyclonal nature of their dissemination

    Poly[[tris­(μ2-4,4′-bipyridine N,N′-di­oxide)hexa­nitratodieuropium(III)] dichloro­methane disolvate]

    Get PDF
    The title one-dimensional coordination network, {[Eu2(NO3)6(C10H8N2O2)3]·2CH2Cl2}n, is isostructural with the previously reported Tb and Tl coordination networks and to its Gd analog. The EuIII cation is coordinated in a distorted tricapped trigonal-prismatic fashion by nine O atoms from three bridging 4,4′-bipyridine N,N′-dioxide ligands and three chelating nitrate anions. None of the atoms lie on a special position, but there is an inversion center located between the rings of one of the ligands. The network topology is ladder-like, and each ladder inter­acts with six neighboring ladders through C—H⋯O hydrogen bonds. The packing motif of the ladders allows for the formation of channels that run parallel to the a axis; these channels are filled with CH2Cl2 solvent mol­ecules that inter­act with the ladders through C—H⋯O hydrogen bonds

    Halothane potentiates the alcohol-adduct induced TNF-alpha release in heart endothelial cells

    Get PDF
    BACKGROUND: The possibility exists for major complications to occur when individuals are intoxicated with alcohol prior to anesthetization. Halothane is an anesthetic that can be metabolized by the liver into a highly reactive product, trifluoroacetyl chloride, which reacts with endogenous proteins to form a trifluoroacetyl-adduct (TFA-adduct). The MAA-adduct which is formed by acetaldehyde (AA) and malondialdehyde reacting with endogenous proteins, has been found in both patients and animals chronically consuming alcohol. These TFA and MAA-adducts have been shown to cause the release of inflammatory products by various cell types. If both adducts share a similar mechanism of cell activation, receiving halothane anesthesia while intoxicated with alcohol could exacerbate the inflammatory response and lead to cardiovascular injury. METHODS: We have recently demonstrated that the MAA-adduct induces tumor necrosis factor-α (TNF-α) release by heart endothelial cells (HECs). In this study, pair and alcohol-fed rats were randomized to receive halothane pretreatments intra peritoneal. Following the pretreatments, the intact heart was removed, HECs were isolated and stimulated with unmodified bovine serum albumin (Alb), MAA-modified Alb (MAA-Alb), Hexyl-MAA, or lipopolysaccharide (LPS), and supernatant concentrations of TNF-α were measured by ELISA. RESULTS: Halothane pre-treated rat HECs released significantly greater TNF-α concentration following MAA-adduct and LPS stimulation than the non-halothane pre-treated in both pair and alcohol-fed rats, but was significantly greater in the alcohol-fed rats. CONCLUSION: These results demonstrate that halothane and MAA-adduct pre-treatment increases the inflammatory response (TNF-α release). Also, these results suggest that halothane exposure may increase the risk of alcohol-induced heart injury, since halothane pre-treatment potentiates the HEC TNF-α release measured following both MAA-Alb and LPS stimulation

    Cardiometabolic Risk Markers in Indian Children: Comparison with UK Indian and White European Children

    Get PDF
    Objective: UK Indian adults have higher risks of coronary heart disease and type 2 diabetes than Indian and UK European adults. With growing evidence that these diseases originate in early life, we compared cardiometabolic risk markers in Indian, UK Indian and white European children.Methods: Comparisons were based on the Mysore Parthenon Birth Cohort Study (MPBCS), India and the Child Heart Health Study in England (CHASE), which studied 9–10 year-old children (538 Indian, 483 UK Indian, 1375 white European) using similar methods. Analyses adjusted for study differences in age and sex.Results: Compared with Mysore Indians, UK Indians had markedly higher BMI (% difference 21%, 95%CI 18 to 24%), skinfold thickness (% difference 34%, 95%CI 26 to 42%), LDL-cholesterol (mean difference 0.48, 95%CI 0.38 to 0.57 mmol/L), systolic BP (mean difference 10.3, 95% CI 8.9 to 11.8 mmHg) and fasting insulin (% difference 145%, 95%CI 124 to 168%). These differences (similar in both sexes and little affected by adiposity adjustment) were larger than those between UK Indians and white Europeans. Compared with white Europeans, UK Indians had higher skinfold thickness (% difference 6.0%, 95%CI 1.5 to 10.7%), fasting insulin (% difference 31%, 95%CI 22 to 40%), triglyceride (% difference 13%, 95%CI 8 to 18%) and LDL-cholesterol (mean difference 0.12 mmol/L, 95%CI 0.04 to 0.19 mmol/L).Conclusions: UK Indian children have an adverse cardiometabolic risk profile, especially compared to Indian children. These differences, not simply reflecting greater adiposity, emphasize the need for prevention strategies starting in childhood or earlier
    corecore