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1.
Child Abuse Negl ; 141: 106232, 2023 07.
Article in English | MEDLINE | ID: mdl-37220692

ABSTRACT

BACKGROUND: There is a disproportionate representation of Aboriginal children in the Australian Out of Home Care system. An important strategy to ensure Aboriginal children experience trauma informed care that is culturally situated is to have access to Aboriginal practitioners. The experiences of Aboriginal practitioners working in Aboriginal Out of Home Care have not been explored thoroughly. PARTICIPANTS AND SETTING: This community led research was undertaken on Dharawal Country on the South Coast of the Illawarra region, Australia with an Out of Home Care program managed by an Aboriginal Community Controlled Organisation. The study included Aboriginal (n = 50) and non-Aboriginal (n = 3) participants connected through employment or community membership to the organisation. OBJECTIVE: We aimed to explore the wellbeing needs of Aboriginal practitioners working with Aboriginal children in Aboriginal Out of Home Care. METHODS: This co-designed qualitative research project used yarning sessions (individual and group), co-analysis with co-researchers, document analysis and reflexive writing. FINDINGS: Aboriginal practitioners are required to bring their cultural expertise to their work and with this, there is an expectation of cultural leadership and the fulfilling of cultural responsibilities. These elements bring with them emotional labour that must be acknowledged and accounted for in working in the Out of Home Care sector. CONCLUSION: The findings point to the importance of establishing an organisational social and emotional wellbeing framework in recognition of Aboriginal practitioner's specific needs, centring cultural participation as a key wellbeing and trauma informed strategy.


Subject(s)
Australian Aboriginal and Torres Strait Islander Peoples , Foster Home Care , Health Personnel , Child , Humans , Australia , Indigenous Peoples , Health Personnel/psychology
2.
Sci Rep ; 11(1): 5138, 2021 03 04.
Article in English | MEDLINE | ID: mdl-33664420

ABSTRACT

Hops are valued for their secondary metabolites, including bitter acids, flavonoids, oils, and polyphenols, that impart flavor in beer. Previous studies have shown that hop yield and bitter acid content decline with increased temperatures and low-water stress. We looked at physiological traits and differential gene expression in leaf, stem, and root tissue from hop (Humulus lupulus) cv. USDA Cascade in plants exposed to high temperature stress, low-water stress, and a compound treatment of both high temperature and low-water stress for six weeks. The stress conditions imposed in these experiments caused substantial changes to the transcriptome, with significant reductions in the expression of numerous genes involved in secondary metabolite biosynthesis. Of the genes involved in bitter acid production, the critical gene valerophenone synthase (VPS) experienced significant reductions in expression levels across stress treatments, suggesting stress-induced lability in this gene and/or its regulatory elements may be at least partially responsible for previously reported declines in bitter acid content. We also identified a number of transcripts with homology to genes shown to affect abiotic stress tolerance in other plants that may be useful as markers for breeding improved abiotic stress tolerance in hop. Lastly, we provide the first transcriptome from hop root tissue.


Subject(s)
Humulus/genetics , Plant Leaves/genetics , Plant Proteins/genetics , Secondary Metabolism/genetics , Droughts , Gene Expression Regulation, Plant/genetics , Hot Temperature/adverse effects , Humulus/growth & development , Plant Leaves/growth & development , Plant Proteins/biosynthesis , Water/chemistry
3.
Sci Rep ; 10(1): 1581, 2020 01 31.
Article in English | MEDLINE | ID: mdl-32005953

ABSTRACT

Predicting the effects of invasive ecosystem engineering species in new bioregions has proved elusive. In part this is because separating biological effects from purely physical mechanisms has been little studied and yet could help predict potentially damaging bioinvasions. Here we tested the effects of a large bio-engineering fanworm Sabella spallanzanii (Sabella) versus worm-like structures (mimics) on gas and nutrient fluxes in a marine soft bottom sediment. Experimental plots of sediment in Hauraki Gulf (New Zealand) were used to test the hypothesis that ecosystem engineers negatively influence benthic ecosystem function through autogenic mechanisms, facilitating activity by biofouling organisms and competitive exclusion of native infauna. Enhanced physical structure associated with Sabella and mimics increased nitrogen fluxes, community metabolism and reduced denitrification from 23 µmol m-2 h-1 to zero at densities greater than 25 m2. Sabella plots on average had greater respiration (29%), NH4 release (33%), and greater NO3 release (52%) compared to mimics, suggesting allogenic (biological) mechanisms occur, but play a secondary role to autogenic (physical) mechanisms. The dominance of autogenic mechanisms indicates that bio-engineers are likely to cause significant impacts when established, regardless of fundamental differences in recipient regions or identity of the introduced bio-engineer. In the case of Sabella spallanzanii, compromised denitrification has the potential to tip the balance of net solute and gas exchanges and cause further ecological degradation in an already eutrophic system.


Subject(s)
Biodegradation, Environmental , Bioengineering/methods , Biofouling , Ecosystem , Introduced Species , Nitrogen/metabolism , Animals , Aquatic Organisms/metabolism , Biofouling/prevention & control , Geologic Sediments , Oceans and Seas , Polychaeta/metabolism
4.
J Environ Radioact ; 208-209: 106047, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31526956

ABSTRACT

As part of an underground gas migration study, two radioactive noble gases (37Ar and 127Xe) and two stable tracer gases (SF6 and PFDMCH) were injected into a historic nuclear explosion test chimney and allowed to migrate naturally. The purpose of this experiment was to provide a bounding case (natural transport) for the flow of radioactive noble gases following an underground nuclear explosion. To accomplish this, soil gas samples were collected from a series of boreholes and a range of depths from the shallow subsurface (3 m) to deeper levels (~160 m) over a period of eleven months. These samples have provided insights into the development and evolution of the subsurface plume and constrained the relative migration rates of the radioactive and stable gas species in the case when the driving pressure from the cavity is low. Analysis of the samples concluded that the stable tracer SF6 was consistently enriched in the subsurface samples relative to the radiotracer 127Xe, but the ratios of SF6 and 37Ar remained similar throughout the samples.


Subject(s)
Noble Gases/analysis , Nuclear Weapons , Radiation Monitoring , Radioactivity , Explosions , Nevada , Security Measures
5.
BJR Case Rep ; 5(1): 20170074, 2019 Feb.
Article in English | MEDLINE | ID: mdl-31131113

ABSTRACT

We report the case of an 84-year-old male, who presented with septicaemia, abdominal and back pain. The patient had a background of oesophageal carcinoma and had undergone previous oesophagectomy and gastric pull-up operation 10 years ago. A computerised topography scan demonstrated a probable gastro-vertebral communication with a destructive process at the T8/T9 vertebral level. Further evaluation with MRI clearly showed the tract between the two structures and confirmed the diagnosis of spondylodiscitis at the adjacent spinal level. The patient was resuscitated, treated with intravenous antibiotics and kept nil by mouth. A subsequent gastroscopy demonstrated an eroding gastric ulcer at the enteric opening of the tract between the tubal stomach and the spinal column. The diagnosis was discussed with the patient, his family and the surgical multidisciplinary team. Given the extent of disease and his multiple medical co-morbidities, the decision was made for conservative management and symptom control. This is the first case of a gastro-vertebral communication causing spondylodiscitis to be described in the literature.

6.
Sports Med ; 47(12): 2533-2551, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28801751

ABSTRACT

BACKGROUND: Late-stage rehabilitation programs often incorporate 'sport-specific' demands, but may not optimally simulate the in-game volume or intensity of such activities as sprinting, cutting, jumping, and lateral movement. OBJECTIVE: The aim of this review was to characterize, quantify, and compare straight-line running and multi-directional demands during sport competition. DATA SOURCES: A systematic review of PubMed, CINAHL, SPORTDiscus, and Cochrane Central Register of Controlled Trials databases was conducted. STUDY ELIGIBILITY CRITERIA: Studies that reported time-motion analysis data on straight-line running, accelerations/decelerations, activity changes, jumping, cutting, or lateral movement over the course of an entire competition in a multi-directional sport (soccer, basketball, lacrosse, handball, field hockey, futsal, volleyball) were included. STUDY APPRAISAL AND SYNTHESIS METHODS: Data was organized based on sport, age level, and sex and descriptive statistics of the frequency, intensity, time, and volume of the characteristics of running and multi-directional demands were extracted from each study. RESULTS: Eighty-one studies were included in the review (n = 47 soccer, n = 11 basketball, n = 9 handball, n = 7 field hockey, n = 3 futsal, n = 4 volleyball). Variability of sport demand data was found across sports, sexes, and age levels. Specifically, soccer and field hockey demanded the most volume of running, while basketball required the highest ratio of high-intensity running to sprinting. Athletes change activity between 500 and 3000 times over the course of a competition, or once every 2-4 s. Studies of soccer reported the most frequent cutting (up to 800 per game), while studies of basketball reported the highest frequency of lateral movement (up to 450 per game). Basketball (42-56 per game), handball (up to 90 per game), and volleyball (up to 35 per game) were found to require the most jumping. LIMITATIONS: These data may provide an incomplete view of an athlete's straight-line running load, considering that only competition and not practice data was provided. CONCLUSIONS: Considerable variability exists in the demands of straight-line running and multi-directional demands across sports, competition levels, and sexes, indicating the need for sports medicine clinicians to design future rehabilitation programs with improved specificity (including the type of activity and dosage) to these demands.


Subject(s)
Athletic Performance/physiology , Basketball/physiology , Controlled Clinical Trials as Topic , Hockey/physiology , Running/physiology , Soccer/physiology , Adult , Female , Humans , Male , Sports/physiology , Sports Medicine
7.
Epidemiol Infect ; 144(5): 1010-3, 2016 Apr.
Article in English | MEDLINE | ID: mdl-25170765

ABSTRACT

Chagas disease is an important emerging disease in Texas that results in cardiomyopathy in about 30% of those infected with the parasite Trypanosoma cruzi. Between the years 2008 and 2012, about 1/6500 blood donors were T. cruzi antibody-confirmed positive. We found older persons and minority populations, particularly Hispanic, at highest risk for screening positive for T. cruzi antibodies during routine blood donation. Zip code analysis determined that T. cruzi is associated with poverty. Chagas disease has a significant disease burden and is a cause of substantial economic losses in Texas.


Subject(s)
Blood Donors/statistics & numerical data , Chagas Disease/epidemiology , Mass Screening , Trypanosoma cruzi/isolation & purification , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Protozoan/blood , Chagas Disease/parasitology , Female , Humans , Male , Middle Aged , Prevalence , Risk Factors , Seroepidemiologic Studies , Socioeconomic Factors , Texas/epidemiology , Young Adult
8.
Science ; 350(6259): 455-9, 2015 Oct 23.
Article in English | MEDLINE | ID: mdl-26382853

ABSTRACT

Autoantibodies target the RNA binding protein Ro60 in systemic lupus erythematosus (SLE) and Sjögren's syndrome. However, it is unclear whether Ro60 and its associated RNAs contribute to disease pathogenesis. We catalogued the Ro60-associated RNAs in human cell lines and found that among other RNAs, Ro60 bound an RNA motif derived from endogenous Alu retroelements. Alu transcripts were induced by type I interferon and stimulated proinflammatory cytokine secretion by human peripheral blood cells. Ro60 deletion resulted in enhanced expression of Alu RNAs and interferon-regulated genes. Anti-Ro60-positive SLE immune complexes contained Alu RNAs, and Alu transcripts were up-regulated in SLE whole blood samples relative to controls. These findings establish a link among the lupus autoantigen Ro60, Alu retroelements, and type I interferon.


Subject(s)
Alu Elements , Autoantigens/metabolism , Gene Expression Regulation , Lupus Erythematosus, Systemic/genetics , RNA, Small Cytoplasmic/metabolism , Ribonucleoproteins/metabolism , Sjogren's Syndrome/genetics , Antigen-Antibody Complex/immunology , Autoantibodies/immunology , Autoantigens/immunology , Cell Line , Humans , Inflammation/genetics , Interferon Type I , Lupus Erythematosus, Systemic/immunology , RNA/metabolism , RNA, Small Cytoplasmic/immunology , Ribonucleoproteins/immunology , Sjogren's Syndrome/immunology , Transcription, Genetic
9.
Vox Sang ; 108(3): 318-20, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25556667

ABSTRACT

Some blood centres have increased sample volume of in-process cultures to improve detection of bacterial contamination when screening apheresis platelet units. We performed a meta-analysis to evaluate extant published North American data comparing apheresis platelet bacterial contamination rates from 4 ml and 8 ml sample volume. Pooled results indicate an 8 ml sample volume yields higher true-positive rates than 4 ml resulting in a significant increase in the detection rate and interdiction of contaminated units, which should contribute to reduced risk of adverse transfusion outcomes.


Subject(s)
Blood Component Removal/methods , Blood Platelets/microbiology , Blood Safety/methods , Humans , Sample Size
10.
Health Promot J Austr ; 24(1): 32-43, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23575587

ABSTRACT

ISSUES ADDRESSED: Community and school cooking and gardening programs have recently increased internationally. However, despite promising indications, there is limited evidence of their effectiveness. This paper presents the evaluation framework and methods negotiated and developed to meet the information needs of all stakeholders for the Stephanie Alexander Kitchen Garden (SAKG) program, a combined cooking and gardening program implemented in selectively funded primary schools across Australia. METHODS: The evaluation used multiple aligned theoretical frameworks and models, including a public health ecological approach, principles of effective health promotion and models of experiential learning. The evaluation is a non-randomised comparison of six schools receiving the program (intervention) and six comparison schools (all government-funded primary schools) in urban and rural areas of Victoria, Australia. A mixed-methods approach was used, relying on qualitative measures to understand changes in school cultures and the experiential impacts on children, families, teachers, parents and volunteers, and quantitative measures at baseline and 1 year follow up to provide supporting information regarding patterns of change. RESULTS: The evaluation study design addressed the limitations of many existing evaluation studies of cooking or garden programs. The multistrand approach to the mixed methodology maintained the rigour of the respective methods and provided an opportunity to explore complexity in the findings. Limited sensitivity of some of the quantitative measures was identified, as well as the potential for bias in the coding of the open-ended questions. CONCLUSION: The SAKG evaluation methodology will address the need for appropriate evaluation approaches for school-based kitchen garden programs. It demonstrates the feasibility of a meaningful, comprehensive evaluation of school-based programs and also demonstrates the central role qualitative methods can have in a mixed-method evaluation. So what? This paper contributes to debate about appropriate evaluation approaches to meet the information needs of all stakeholders and will support the sharing of measures and potential comparisons between program outcomes for comparable population groups and settings.


Subject(s)
Feeding Behavior , Gardening , Health Promotion , Schools , Focus Groups , Pilot Projects , Qualitative Research , Victoria
11.
J Virol ; 87(2): 900-11, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23135728

ABSTRACT

Despite the eradication of smallpox, orthopoxviruses (OPV) remain public health concerns. Efforts to develop new therapeutics and vaccines for smallpox continue through their evaluation in animal models despite limited understanding of the specific correlates of protective immunity. Recent monkeypox virus challenge studies have established the black-tailed prairie dog (Cynomys ludovicianus) as a model of human systemic OPV infections. In this study, we assess the induction of humoral immunity in humans and prairie dogs receiving Dryvax, Acam2000, or Imvamune vaccine and characterize the proteomic profile of immune recognition using enzyme-linked immunosorbent assays (ELISA), neutralization assays, and protein microarrays. We confirm anticipated similarities of antigenic protein targets of smallpox vaccine-induced responses in humans and prairie dogs and identify several differences. Subsequent monkeypox virus intranasal infection of vaccinated prairie dogs resulted in a significant boost in humoral immunity characterized by a shift in reactivity of increased intensity to a broader range of OPV proteins. This work provides evidence of similarities between the vaccine responses in prairie dogs and humans that enhance the value of the prairie dog model system as an OPV vaccination model and offers novel findings that form a framework for examining the humoral immune response induced by systemic orthopoxvirus infection.


Subject(s)
Antibodies, Viral/blood , Host-Pathogen Interactions , Monkeypox virus/immunology , Monkeypox virus/pathogenicity , Poxviridae Infections/immunology , Proteome/analysis , Smallpox Vaccine/immunology , Animals , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Humans , Neutralization Tests , Poxviridae Infections/pathology , Protein Array Analysis , Sciuridae , Smallpox Vaccine/administration & dosage
12.
J Chromatogr A ; 1251: 236-239, 2012 Aug 17.
Article in English | MEDLINE | ID: mdl-22771068

ABSTRACT

A new disposable adsorbent material for fast anion-exchange capture of nano-complexes without prefiltering, clarification or pre-processing of samples was developed based on plastic microcapillary films (MCFs). An MCF containing 19 parallel microcapillaries, each with a mean internal diameter of 142 ± 10 µm, was prepared using a melt extrusion process from an ethylene-vinyl alcohol copolymer (EVOH). The MCF internal surfaces were functionalised using branched chain chemistries to attach quaternary amine groups producing an anion-exchange adsorbent. The purification of nano-complexes using this newly fabricated MCF-EVOH-Q was successfully demonstrated with the capture of lentivirus from pre-filtered culture harvest. This 5m chromatographic substrate was found to bind and elute ∼40% of bound lentivirus or 2.5 × 10(6)infectious units (ifu). The unique properties of this chromatographic substrate that allow the passage of large particulates was further demonstrated with the capture of lentiviral particles from unfiltered un-processed culture media containing cells and cell debris. Using this approach, 56% or 1 × 10(7)ifu of captured lentivirus was eluted. A device based on this new material might be used at an early stage in clinical lentiviral production to harvest lentiviral particles, directly from bioreactors.


Subject(s)
Cell Culture Techniques/methods , Chromatography, Ion Exchange/instrumentation , Chromatography, Ion Exchange/methods , Genetic Vectors/isolation & purification , Lentivirus/isolation & purification , Cell Line, Tumor , Electrophoresis, Polyacrylamide Gel , HEK293 Cells , Humans , Polyvinyls/chemistry
13.
Rev Sci Instrum ; 81(10): 10D534, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21033888

ABSTRACT

The light detection and ranging Thomson scattering (TS) diagnostic is advantageous since it only requires a single view port into the tokamak. This technique requires a short pulse laser at high energy, usually showing a limited repetition rate. Having multiple lasers will increase the repetition rate. This paper presents a scanning mirror as a laser beam combiner. Measurements of the position accuracy and jitter show that the pointing stability of the laser beam is within ±25 µrad for over tens of seconds. A control feedback loop is implemented to demonstrate the long term stability. Such a system could be applied for ITER and JET.

14.
Leukemia ; 23(11): 2075-80, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19776762

ABSTRACT

In probing the cell of origin in malignant B cells, an imprint of somatic hypermutation (SHM) in immunoglobulin (Ig) variable (V) region genes delineates antigen encounter, and identifying the precise pathway generating SHM in the normal B-cell counterpart becomes relevant. SHM remains the definitive memory imprint in normal human B cells, but CD27 expression also delineates memory. Recently, dye extrusion adenosine triphosphate-binding transporter assays identified circulating isotype-switched memory B cells that lacked CD27, yet exhibited low levels of SHM. To extend findings, we report a pre-switched CD27(-ve) circulating memory B-cell population in normal blood using comparable assays, and isolated CD19(+)IgM(+)D(+)CD27(-ve) cells (>99% purity) for the analysis of IGHV5/IGHV3-IGHM transcripts. Of these (n=334), approximately 78% were germ line and naive B cell derived. Strikingly, 21.9% of the transcripts were mutated. They showed 3-5 mutations (13.5% of sequences) and >5 mutations (8.4% of sequences) per transcript. Accrual of mutations in a subset of CD19(+)IgM(+)D(+)CD27(-ve) cells define a new circulating pre-switched memory B-cell pool, present in substantial numbers in the population harboring naive B cells. These CD19(+)IgM(+)D(+)CD27(-ve) memory B cells may have a distinct lineage and function, and seem relevant to understanding origins of malignant B cells, in particular those of hairy cell leukemia cells, which display mutated V genes yet lack CD27 expression.


Subject(s)
B-Lymphocyte Subsets/immunology , Immunoglobulin Heavy Chains/genetics , Immunologic Memory/genetics , Leukemia, Hairy Cell/immunology , Somatic Hypermutation, Immunoglobulin/genetics , Tumor Necrosis Factor Receptor Superfamily, Member 7/metabolism , ATP Binding Cassette Transporter, Subfamily B , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Antigens, CD19/metabolism , B-Lymphocyte Subsets/cytology , B-Lymphocyte Subsets/metabolism , Cell Lineage/immunology , Flow Cytometry , Humans , Immunoglobulin D/metabolism , Immunoglobulin M/metabolism , Immunologic Memory/immunology , Leukemia, B-Cell/genetics , Leukemia, B-Cell/immunology , Leukemia, B-Cell/pathology , Leukemia, Hairy Cell/genetics , Leukemia, Hairy Cell/pathology
17.
Mar Pollut Bull ; 56(3): 386-96, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18191954

ABSTRACT

Policy makers are increasingly recognising the role of environmental valuation to guide and support the management and conservation of biodiversity. This paper presents a goods and services approach to determine the economic value of marine biodiversity in the UK, with the aim of clarifying the role of valuation in the management of marine biodiversity. The goods and services resulting from UK marine biodiversity are detailed, and 8 of the 13 services are valued in monetary terms. It is found that a decline in UK marine biodiversity could result in a varying, and at present unpredictable, change in the provision of goods and services, including reduced resilience and resistance to change, declining marine environmental health, reduced fisheries potential, and loss of recreational opportunities. The results suggest that this approach can facilitate biodiversity management by enabling the optimal allocation of limited management resources and through raising awareness of the importance of marine biodiversity.


Subject(s)
Biodiversity , Conservation of Natural Resources/economics , Environmental Health/economics , Marine Biology , Animals , Conservation of Natural Resources/methods , Cost-Benefit Analysis , Environmental Health/methods , Fisheries/economics , Fisheries/methods , Fishes , Food Chain , Humans , Recreation/economics , United Kingdom
18.
Article in English | MEDLINE | ID: mdl-18076115

ABSTRACT

BACKGROUND: Chromium(III) is generally thought to be an essential trace element that allows for proper glucose metabolism. However, chromium(III) picolinate, Cr(pic)3, a popular dietary supplement form of chromium, has been shown to be capable of generating hydroxyl radicals and oxidative DNA damage in rats. The cation [Cr3O(O2CCH2CH3)(6(H2O)3]+, Cr3, has been studied as an alternative supplemental source of chromium. It has been shown to increase insulin sensitivity and lower glycated hemoglobin levels in rats, making it attractive as a potential therapeutic treatment for gestational diabetes. To date, no studies have been published regarding the safety of Cr3 supplementation to a developing fetus. METHODS: From gestation days (GD) 6-17, mated CD-1 female mice were fed diets delivering either 25 mg Cr/kg/day as Cr(pic)(3), 3.3 or 26 mg Cr/kg/day as Cr3, or the diet only to determine if Cr3 could cause developmental toxicity. Dams were sacrificed on GD 17, and their litters were examined for adverse effects. RESULTS: No signs of maternal toxicity were observed. No decrease in fetal weight or significantly increased incidence of skeletal defects was observed in the Cr3 or Cr(pic)3 exposed fetuses compared to the controls. CONCLUSION: Maternal exposure to either Cr(pic)3 or Cr3 at the dosages employed did not appear to cause deleterious effects to the developing offspring in mice.


Subject(s)
Dietary Supplements , Embryonic Development/drug effects , Fetal Development/drug effects , Organometallic Compounds/toxicity , Picolinic Acids/toxicity , Teratogens/toxicity , Administration, Oral , Animals , Dose-Response Relationship, Drug , Female , Maternal Exposure , Mice , Mice, Inbred Strains , Organometallic Compounds/classification , Picolinic Acids/classification , Pregnancy , Teratogens/classification
19.
Heart ; 94(4): 446-9, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17483129

ABSTRACT

BACKGROUND: Patients with heart failure and a normal left ventricular ejection fraction have significantly reduced left ventricular long-axis function. This paper proposes an explanation for this apparent paradox and suggests a new mechanism of "diastolic" heart failure. METHOD: The effect of changes in left ventricular hypertrophy on stroke volume and ejection fraction in non-dilated left ventricles was calculated using the area-length method. Further, the effect of a reduction in long-axis shortening on these parameters was determined. RESULTS: Increasing left ventricular hypertrophy resulted in augmentation of systolic wall thickening and ejection fraction but not stroke volume when long-axis shortening was normal. In the presence of abnormal long-axis function, stroke volume was reduced but ejection fraction was preserved. CONCLUSION: The model predicts that the normal ejection fraction in patients with heart failure may be explained by the presence of left ventricular hypertrophy. The resulting amplified radial thickening in the setting of reduced long-axis shortening explains the preservation of ejection fraction. The reduced stroke volume in the precompensated state rather than diastolic dysfunction may be the cause of heart failure.


Subject(s)
Heart Failure/physiopathology , Models, Cardiovascular , Stroke Volume , Heart Failure/etiology , Humans , Hypertrophy, Left Ventricular/complications , Hypertrophy, Left Ventricular/physiopathology , Ventricular Dysfunction, Left/physiopathology
20.
Mar Pollut Bull ; 54(3): 253-65, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17266994

ABSTRACT

This paper identifies and defines ecosystem goods and services provided by marine biodiversity. Case studies have been used to provide an insight into the practical issues associated with the assessment of marine ecosystem goods and services at specific locations. The aim of this research was to validate the definitions of goods and services, and to identify knowledge gaps and likely difficulties of quantifying the goods and services. A validated theoretical framework for the assessment of goods and services is detailed, and examples of the goods and services at a variety of case study areas are documented. These results will enable future assessments of marine ecosystem goods and services. It is concluded that the utilisation of this goods and services approach has the capacity to play a fundamental role in the Ecosystem Approach, by enabling the pressures and demands of society, the economy and the environment to be integrated into environmental management.


Subject(s)
Biodiversity , Conservation of Natural Resources/economics , Marine Biology/economics , Animals , Biodegradation, Environmental , Climate , Culture , Europe , Food , Food Chain , Gases , Humans , Oceans and Seas , Recreation
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