72 results on '"Vella, K."'
Search Results
2. A comparative study using thrombin generation and three different INR methods in patients on Vitamin K antagonist treatment
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Riva, N., Vella, K., Meli, S., Hickey, K., Zammit, D., Calamatta, C., Makris, M., Kitchen, S., Ageno, W., and Gatt, A.
- Published
- 2017
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3. The effect of DOAC‐Stop® on several oral and parenteral anticoagulants
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Riva, N., Vella, K., Hickey, K., Gatt, P., Grima, C., Zammit, D., Ageno, W., Kitchen, S., Makris, M., and Gatt, A.
- Published
- 2021
4. ISL1 Is Necessary for Maximal Thyrotrope Response to Hypothyroidism
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Castinetti, F., Brinkmeier, M. L., Mortensen, A. H., Vella, K. R., Gergics, P., Brue, T., Hollenberg, A. N., Gan, L., and Camper, S. A.
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- 2015
5. Use of albumin in intensive care units in the United Kingdom
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Rowan, K, Vella, K, McCormick, BA, and Brown, JM
- Published
- 2001
6. PITX2 AND PITX1 Regulate Thyrotroph Function and Response to Hypothyroidism
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Castinetti, F., Brinkmeier, M. L., Gordon, D. F., Vella, K. R., Kerr, J. M., Mortensen, A. H., Hollenberg, A., Brue, T., Ridgway, E. C., and Camper, S. A.
- Published
- 2011
7. Expression of the Hypothalamic Transcription Factor Nhlh2 is Dependent on Energy Availability
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Vella, K. R., Burnside, A. S., Brennan, K. M., and Good, D. J.
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- 2007
8. Genetic analysis of NHLH2 and its putative role in bovine body weight control
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Brennan, K. M., Vella, K. R., and Good, D. J.
- Published
- 2006
9. Use of Albumin in Intensive Care Units in the United Kingdom
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Brown, J.M., McCormick, B.A., Vella, K., and Rowan, K.
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- 2001
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10. Higher order multiple pregnancy outcomes in the Maltese islands 2000-2004
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Charles Savona-Ventura, Gatt, M., Vella, K., and Grima, S.
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Multiple pregnancy -- Malta ,Pregnancy -- Statistics ,Multiple pregnancy -- Complications ,Birth size - Abstract
Higher order multiple births have increased significantly in the last decades throughout the developed world. In spite of advances in obstetric care seen throughout the second half of the twentieth century, the perinatal outcomes associated with a multiple pregnancy remain associated with increased morbidity and mortality for the mother and the infants. This study attempts to assess the characteristics and outcomes of these maternities in the Maltese population. The National maternity data for 2000-2004 was analysed (19,935 maternities; 20,215 births) and various outcome parameters were statistically compared between higher order births to singleton births using the chi square test. While the twin maternity rate during the period stood at 1.26%, the triplet maternity rate stood at 0.06% and quadruplet maternities 0.01%. Artificial reproductive technology was used in 27.8% of triplets and 50.0% in quadruplets; in contrast to 0.7% in singleton maternities (p, peer-reviewed
- Published
- 2008
11. Review of outcome measures used in adult critical care.
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Black NA, Jenkinson C, Hayes JA, Young D, Vella K, Rowan KM, Daly K, Ridley S, Black, N A, Jenkinson, C, Hayes, J A, Young, D, Vella, K, Rowan, K M, Daly, K, and Ridley, S
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- 2001
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12. Surfactant Associated Bacteria in the Sea Surface Microlayer: Case Studies in the Straits of Florida and the Gulf of Mexico.
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Hamilton, B., Dean, C., Kurata, N., Vella, K., Soloviev, A., Tartar, A., Shivji, M., Matt, S., Perrie, W., Lehner, S., and Zhang, B.
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SURFACE active agents ,MARINE bacteria ,REMOTE sensing ,HIGH resolution imaging ,RADARSAT satellites - Abstract
Copyright of Canadian Journal of Remote Sensing is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2015
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13. Teamwork and safety attitudes among staff in critical care units and the relationship to patient mortality
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Rowan, K, Brady, A, Vella, K, Boyden, J, and Sexton, J
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Poster Presentation - Published
- 2004
14. Analysing governance of Australia's system of landscape-based greenhouse gas abatement.
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Dale, A.P., Vella, K., and McKee, J.
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GREENHOUSE gases ,ABATEMENT (Atmospheric chemistry) ,CONSERVATION of natural resources ,CLEAN energy ,ENVIRONMENTAL protection - Abstract
Healthy governance systems are key to delivering effective outcomes in any broad domain of natural resource management (NRM). One of Australia's emerging NRM governance domains is our national framework for greenhouse gas abatement (GGA), as delivered through a wide range of management practices in the Australian landscape. The emergingLandscape-Based GGA Domainrepresents an innovative governance space that straddles both the nation's broaderNRM Policy and Delivery DomainandAustralia's GGA Domain. As a point-in-time benchmark, we assess the health of this hybrid domain as it stood at the end of 2013. At that time, the domain was being progressed through the Australian government's Clean Energy Package and, more particularly, its Carbon Farming Initiative (CFI). While significant changes are currently under development by a new Australian government, this paper explores key areas of risk within the governance system underpinning this emerging hybrid domain at that point in time. We then map some potential reform or continuous improvement pathways required (from national to paddock scale) with the view to securing improved landscape outcomes over time through widespread GGA activities. [ABSTRACT FROM AUTHOR]
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- 2014
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15. Twenty years of pacifying responses to environmental management.
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Jacobson, C., Hughey, K.F.D., Lynch, A.J.J., Nursey-Bray, M., O'Connell, M., Munro, P.G., Vella, K., Whiley, D., Dovers, S., and Carter, R.W. (Bill)
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ENVIRONMENTAL management ,CLIMATE change ,MARINE ecology ,BIODIVERSITY - Abstract
Using a state, pressure, response framework, we provide an evidence-based reflection on environmental outcomes in Australia and New Zealand across the domains of climate change, biodiversity, freshwater and marine management, emphasising the role of Indigenous and business perspectives. Significant developments have occurred in the past 20 years through affirmation of Indigenous rights and responsibilities. Responses to climate change have tended to emphasise passive risk management with unclear outcomes. Despite meeting biodiversity protection targets, outcomes are worsening, suggesting a need to challenge the dualistic preservation/production land categorisations. In freshwater and marine management, a mix of collaborative and market-based responses has emerged, although their efficacy remains untested. A reliance on voluntary approaches by business makes critical assessment of progress difficult. Thus, despite strong progress in some areas, the adaptiveness of environmental management remains limited, and many indicators suggest continuing decline in environmental condition. Our responses have been largely pacifying in nature, leading to perverse outcomes and failure to acknowledge alternatives that might address deteriorating environmental conditions. A shift is needed towards deliberative policy experimentation that truly values the application of novel and diversified approaches and facilitates integrated learning across environmental domains. [ABSTRACT FROM AUTHOR]
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- 2014
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16. Cervical carcinoma in the Maltese population.
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Buttigieg GG, Savona-Ventura C, Vella K, and Cassar O
- Published
- 2008
17. Occupational therapy for children with acquired brain injury: a survey of current practice.
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Jones P, Drummond A, and Vella K
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- 2007
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18. Wait-free cache-affinity thread scheduling.
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Debattista, K., Vella, K., and Cordina, J.
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ALGORITHMS , *THREADS (Computer programs) , *CACHE memory , *COMPUTER software , *BATCH processing in electronic data processing - Abstract
Focuses on various thread scheduling algorithms for multithreaded applications. Features of cache-affinity thread scheduling technique; Benefits of wait-free scheduling; Role of batching as a scheduling strategy which improves cache exploitation.
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- 2003
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19. Testing and Modeling Ethernet Switches and Networks for Use in ATLAS High-Level Triggers.
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Dobinson, R. W., Haas, S., Korcyl, K., LeVine, M. J., Lokier, J., Martin, B., Meirosu, C., Saka, F., and Vella, K.
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LOCAL area networks ,TRIGGER circuits - Abstract
Presents a study on a multilayered local area network for evaluating the performance of ATLAS triggers. Modeling of the network; Measurement of central processing unit utilization; Testing of a gigabite ethernet switch.
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- 2001
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20. Research priorities in critical care medicine in the UK.
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Goldfrad, Caroline, Vella, Keryn, Bion, Julian F., Rowan, Kathy M., Black, Nick A., Goldfrad, C, Vella, K, Bion, J F, Rowan, K M, and Black, N A
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CRITICAL care medicine ,CATASTROPHIC illness ,INTENSIVE care units ,LIKERT scale ,HEALTH outcome assessment ,ACADEMIC medical centers ,ATTITUDE (Psychology) ,COMPARATIVE studies ,FOCUS groups ,HEALTH planning ,HOSPITALS ,HOSPITAL medical staff ,RESEARCH methodology ,MEDICAL cooperation ,MEDICAL personnel ,NEEDS assessment ,PUBLIC hospitals ,RESEARCH ,EVALUATION research ,HOSPITAL nursing staff ,PSYCHOLOGY - Abstract
Objectives: To establish priorities for research in critical care medicine in the UK using survey and nominal group (NG) techniques.Design: The senior doctor and nurse from 325 intensive care units (ICUs) in the UK were invited to contribute up to ten research questions relevant to intensive care organisation, practice or outcomes. These were then ranked twice using a Likert scale by a panel (nominal group) consisting of ten doctors (two trainees) and two nurses from university teaching and district general (community) hospitals. The first ratings were performed privately, and the second after group discussion. Thirty questions, ten each with strong, moderate or weak support, were then returned for rating by the originating ICU staff and the results compared with those of the NG.Results: One hundred eighty-five respondents (35.6 % university teaching, 62.1% district general, 2.3 % not stated) provided 811 questions of which 722 were research hypotheses. The most frequently identified topics were the evaluation of high dependency care, ICU characteristics, treatments for acute lung injury and acute renal failure, nurse:patient ratios, pulmonary artery catheterisation, aspects of medical and nursing practice, protocol evaluation, and interhospital transfers. These were condensed into 100 topics for consideration by the NG. Discussion and re-rating by the group resulted in strong support being offered for 37 topics, moderate support for 48, and weak support for 21. Following circulation of ten questions from each category, nine questions achieved strong support from both ICU staff and the NG. These were the effect on outcomes from critical illness of early intervention, high dependency care, nurse:patient ratios, interhospital transfers, early enteral feeding, optimisation of perioperative care, hospital type, regionalisation of paediatric intensive care and the use of pulmonary artery catheters. The absence of any questions relating to interventions targetting mediators of the immuno-inflammatory response could be a consequence of the failure of recent studies in sepsis to demonstrate benefits in outcome.Conclusions: The intensive care community in the UK appears to prioritise research into organisational aspects of clinical practice and practical aspects of organ-system support. Health services research and the biological sciences need to develop collaborative methods for evaluating interventions and outcomes. [ABSTRACT FROM AUTHOR]- Published
- 2000
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21. Long COVID Syndrome: A Case-Control Study.
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Xuereb RA, Borg M, Vella K, Gatt A, Xuereb RG, Barbara C, Fava S, and Magri CJ
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- Humans, Female, Male, Middle Aged, Case-Control Studies, Adult, Dyspnea etiology, SARS-CoV-2, Fatigue etiology, C-Reactive Protein analysis, Follow-Up Studies, COVID-19 complications, Post-Acute COVID-19 Syndrome, Quality of Life
- Abstract
Background: Acute coronavirus disease 2019 (COVID-19) causes various cardiovascular complications. However, it is unknown if there are cardiovascular sequelae in the medium and long-term. The aim of this study was dual. Firstly, we wanted to investigate symptomatology and health-related quality of life (HRQoL) at medium-term follow-up (6 months post-COVID). Secondly, we wanted to assess whether history of COVID-19 and persistent shortness of breath at medium-term follow-up are associated with ongoing inflammation, endothelial dysfunction, and cardiac injury., Methods: A case-control study was performed. Virologically proven COVID-19 cases and age- and gender-matched controls were interviewed to assess symptoms and HRQoL. Biochemical tests were also performed., Results: The study comprised 174 cases and 75 controls. The mean age of the participants was 46.1±13.8 years. The median follow-up was 173.5 days (interquartile range 129-193.25 days). There was no significant difference in the demographics between cases and controls. At follow-up, cases had a higher frequency of shortness of breath, fatigue, arthralgia, abnormal taste of food (P <.001), and anosmia. Cases also exhibited worse scores in the general health and role physical domains of the Short Form Survey-36. High-sensitivity C-reactive protein (hsCRP) was significantly higher in the cases, and there was a positive correlation of hsCRP with time. Significant determinants of shortness of breath were age, female gender and white cell count, troponin I, and lower hemoglobin levels at follow-up., Conclusion: Post-COVID-19 patients have persistent symptomatology at medium-term follow-up. Higher hsCRP in cases and the positive association of hsCRP with time suggest ongoing systemic inflammation in patients persisting for months after COVID-19., (Copyright © 2023 Elsevier Inc. All rights reserved.)
- Published
- 2025
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22. Conceptualizing social risk in relation to climate change and assisted ecosystem adaptation.
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Lockie S, Graham V, Taylor B, Baresi U, Maclean K, Paxton G, and Vella K
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Realizing positive social and environmental outcomes from assisted ecosystem adaptation requires the management of complex, uncertain, and ambiguous risks. Using assisted coral reef adaptation as a case study, this article presents a conceptual framework that defines social impacts as the physical and cognitive consequences for people of planned intervention and social risks as potential impacts transformed into objects of management through assessment and governance. Reflecting on its multiple uses in the literature, we consider "social risk" in relation to risks to individuals and communities, risks to First Peoples, risks to businesses or project implementation, possibilities for amplified social vulnerability, and risk perceptions. Although much of this article is devoted to bringing clarity to the different ways in which social risk manifests and to the multiple characters of risk and uncertainty, it is apparent that risk governance itself must be an inherently integrative and social process., (© 2024 The Author(s). Risk Analysis published by Wiley Periodicals LLC on behalf of Society for Risk Analysis.)
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- 2024
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23. Demographics of the members of the special interest group for early career medical physicists: A statistical analysis of survey results.
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Vella K, Irazola Rosales L, Jreije A, Katlapa A, Ovejero J, Fanou AM, and Tzoumi N
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- Surveys and Questionnaires, Humans, Europe, Demography, Male, Female, Health Physics
- Abstract
Introduction: The Early Career Medical Physicists Special Interest Group (SIG_FREC) that operates within EFOMP aims to represent individuals with less than 10 years of experience working as medical physics professionals. The purpose of this survey was to better understand the specific needs and expectations of early-career medical physicists across Europe. The aim of this study was to allow these early-career professionals to voice their ideas within EFOMP and provide insights into their challenges and opportunities while also providing them with the possibility of making suggestions for the growth of the SIG. Doing this, the members can be better equipped to be future leaders of the Medical Physics profession in their own country and in Europe., Methods: The Steering Committee of SIG_FREC developed a questionnaire and distributed it to its members., Results: Out of the total number of members of the SIG_FREC at the time of the questionnaire (97 members), 42 of them responded to the survey yielding a response rate of 43%. These provided valuable insights based on their experiences about medical physics in their country., Conclusion: The responses to the questionnaire provided a snapshot of the opinion of early-career medical physicists, representing a wide geographical distribution across Europe. The feedback from SIG_FREC members highlighted potential future operations within EFOMP., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Associazione Italiana di Fisica Medica e Sanitaria. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2024
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24. A comparative in vitro study of the anticoagulant effect of branded versus generic rivaroxaban.
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Mangion K, Vella K, Gatt A, Vella AM, Borg M, Borg-Aquilina D, Douxfils J, Camilleri L, and Riva N
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- Humans, Tandem Mass Spectrometry, Research Design, Fibrinogen, Anticoagulants pharmacology, Anticoagulants therapeutic use, Rivaroxaban pharmacology, Rivaroxaban therapeutic use, Hemostatics
- Abstract
Background: Several generic formulations of rivaroxaban were recently marketed to be used interchangeably with their branded equivalent. However, there have been no previously published studies that directly compared the in vitro anticoagulant effect of branded vs. generic rivaroxaban. The aim of this in vitro study was to compare the effects of three raw rivaroxaban materials, obtained from the branded (Xarelto®) and two generic (Rivarolto® and Rivaroxaban Sandoz®) rivaroxaban formulations on an array of coagulation assays., Methods: A pool of normal plasma was spiked with several concentrations of the three rivaroxaban (range 50-750 ng/ml). The concentrations were assessed with a rivaroxaban calibrated anti-Xa assay and confirmed by ultra-high-performance liquid chromatography-mass spectrometry coupled with tandem mass spectrometry (UHPLC-MS/MS). The following assays were performed: Prothrombin time (PT), activated Partial Thromboplastin time (aPTT), Diluted Russell's Viper Venom Test (dRVVT), Thrombin time (TT), Clauss Fibrinogen, Factor VII, VIII and IX assays, and thromboelastography., Results: The results obtained by the three rivaroxaban at similar concentrations were comparable. Increasing concentrations of the three rivaroxaban showed a strong positive correlation with the PT, aPTT and dRVVT assays (r > 0.95, p < 0.01 for all), and a strong negative correlation with the Factors assays (r < -0.95, p < 0.01 for all). TT and Clauss Fibrinogen were not affected by rivaroxaban. No significant difference was identified in the mean assays' results obtained by the three rivaroxaban., Conclusion: This study showed that the branded and generic rivaroxaban exert an identical in vitro anticoagulant effect across a wide range of concentrations., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to declare in relation to this study. This study was supported by grants from the University of Malta, Research Seed Fund, and from the Faculty of Health Sciences, University of Malta., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2024
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25. Navigating through the haemostatic paradox in kidney failure: A practical overview.
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Caruana J, Riva N, Vella K, Davenport A, and Gatt A
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- Humans, Anticoagulants therapeutic use, Hemostasis, Hemostatics therapeutic use, Kidney Failure, Chronic complications, Kidney Failure, Chronic therapy, Renal Insufficiency, Chronic complications
- Abstract
Chronic kidney disease (CKD) affects around 9.1% of humankind globally resulting in a significant health burden. Some of these individuals will also require renal replacement therapy with dialysis due to complete kidney failure. Patients with CKD are known to be at increased risk of both bleeding and thrombosis. Often it is very difficult to manage these yin and yang since both risks tend to co-exist. Clinically, very few studies have looked at the effects of antiplatelet agents and anticoagulants in this highly vulnerable subgroup of medical patients and evidence is very limited. This review attempts to explain the current state-of-the-art regarding the basic science of haemostasis in patients with end-stage kidney disease. We also try to transfer this knowledge into the clinics by looking at some common haemostasis challenges that are encountered in this cohort of patients and what evidence and guidance there is for their optimal management., (© 2023 British Society for Haematology and John Wiley & Sons Ltd.)
- Published
- 2023
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26. Thyroid dysfunction in pregnancy - a retrospective observational analysis of a Maltese cohort.
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Vella K, Vella S, Savona-Ventura C, and Vassallo J
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- Infant, Newborn, Humans, Female, Pregnancy, Adult, Retrospective Studies, Cesarean Section, Birth Weight, Fetal Growth Retardation, Pregnancy Outcome epidemiology, Premature Birth epidemiology, Thyroid Diseases epidemiology, Hypothyroidism epidemiology, Hypothyroidism complications, Pregnancy Complications epidemiology, Hyperthyroidism epidemiology
- Abstract
Background: Thyroid dysfunction is known to adversely affect pregnancy. This study evaluates the prevalence of thyroid disorders and explores their association with pregnancy complications/comorbidities and modes of delivery in the Maltese pregnant population over a ten year period., Design: A population based observational study., Method: We analysed data from the National Obstetrics Information Service of the Department of Health Informations and Research (NOIS) for all births delivered in Malta between 2006 and 2016. Cases identified and recorded by NOIS to have had some form of thyroid dysfunction during pregnancy were confirmed by cross-referencing with laboratory results found in patients' medical records and/or iSOFT® database system. Using the Statistical Package for the Social sciences (SPSS®) demographic data, past obstetric and medical history and obstetric outcomes were analysed for pregnancies with thyroid dysfunction and compared to data pertaining to pregnancies in euthyroid patients, that is those with no recorded thyroid dysfunction on NOIS. Chi square/Fisher's exact test were used to compare categorical variables while ANOVA/Mann-Whitney U test was used to compare continuous variables. Statistical significance was defined by a two-sided p value <0.05., Results: Data was available for 46,283 women (mean [SD] age = 29.2 [5.4] years). 587 pregnancies (1.3%) suffered from thyroid dysfunction. Of these, 67.3% were hypothyroid, 3.2% had hyperthyroidism, 28.3% had isolated hypothyroxinaemia (IHT) while 1.2% had a history of thyroid carcinoma. Patients with IHT and hypothyroidism were older than euthyroid patients (p < 0.001). IHT and hypothyroid patients had a statistically significant higher body mass index (BMI) than euthyroid women (p=0.001 for hypothyroid women, p = 0.035 for IHT). Hypothyroid and IHT women were more likely to have had a previous lower segment caesarean section (p=0.043, and 0.006 respectively). Type 1 diabetes and gestational diabetes p = 0.012) were more common associated comorbidities in hypothyroid pregnancies. Offspring of patients with IHT had a higher birth weight than those born to euthyroid patients (p=0.009). Patients with hyperthyroidism were found to have a significantly increased risk of early preterm delivery before 34 weeks of gestation and were also more likely to have suspected intrauterine growth restriction and low mean birth weight. We report no significant differences in past history of obstetric loss, antenatal complications, mode of delivery, gestational age at delivery and postpartum haemorrhage rates across thyroid categories., Conclusions: Available evidence suggests that thyroid dysfunction is more likely in the setting of older age, and higher body mass index. Moreover, it impacts on neonatal birth weight, rates of early preterm delivery and intrauterine growth restriction., (© 2022. The Author(s).)
- Published
- 2022
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27. Collaborative Sense-Making in Genomic Research: The Role of Visualisation.
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Rittenbruch M, Vella K, Brereton M, Hogan JM, Johnson D, Heinrich J, and O'Donoghue S
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- Communication, Genomics, Chromosome Mapping, Computer Graphics, Software
- Abstract
Genomic research emerges from collaborative work within and across different scientific disciplines. A diverse range of visualisation techniques has been employed to aid this research, yet relatively little is known as to how these techniques facilitate collaboration. We conducted a case study of collaborative research within a biomedical institute to learn more about the role visualisation plays in genomic mapping. Interviews were conducted with molecular biologists (N = 5) and bioinformaticians (N = 6). We found that genomic research comprises a variety of distinct disciplines engaged in complex analytic tasks that each resist simplification, and their complexity influences how visualisations were used. Visualisation use was impacted by group-specific interactions and temporal work patterns. Visualisations were also crucial to the scientific workflow, used for both question formation and confirmation of hypotheses, and acted as an anchor for the communication of ideas and discussion. In the latter case, two approaches were taken: providing collaborators with either interactive or static imagery representing a viewpoint. The use of generic software for simplified visualisations, and quick production and curation was also noted. We discuss these findings with reference to group-specific interactions and present recommendations for improving collaborative practices through visual analytics.
- Published
- 2022
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28. Exploring technologies to better link physical evidence and digital information for disaster victim identification.
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Lovell D, Vella K, Muñoz D, McKague M, Brereton M, and Ellis P
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Disaster victim identification (DVI) entails a protracted process of evidence collection and data matching to reconcile physical remains with victim identity. Technology is critical to DVI by enabling the linkage of physical evidence to information. However, labelling physical remains and collecting data at the scene are dominated by low-technology paper-based practices. We ask, how can technology help us tag and track the victims of disaster? Our response to this question has two parts. First, we conducted a human-computer interaction led investigation into the systematic factors impacting DVI tagging and tracking processes. Through interviews with Australian DVI practitioners, we explored how technologies to improve linkage might fit with prevailing work practices and preferences; practical and social considerations; and existing systems and processes. We focused on tagging and tracking activities throughout the DVI process. Using insights from these interviews and relevant literature, we identified four critical themes: protocols and training; stress and stressors; the plurality of information capture and management systems; and practicalities and constraints. Second, these findings were iteratively discussed by the authors, who have combined expertise across electronics, data science, cybersecurity, human-computer interaction and forensic pathology. We applied the themes identified in the first part of the investigation to critically review technologies that could support DVI practitioners by enhancing DVI processes that link physical evidence to information. This resulted in an overview of candidate technologies matched with consideration of their key attributes. This study recognises the importance of considering human factors that can affect technology adoption into existing practices. Consequently, we provide a searchable table (as Supplementary information) that relates technologies to the key considerations and attributes relevant to DVI practice, for readers to apply to their own context. While this research directly contributes to DVI, it also has applications to other domains in which a physical/digital linkage is required, and particularly within high stress environments with little room for error.Key points:Disaster victim identification (DVI) processes require us to link physical evidence and digital information. While technology could improve this linkage, experience shows that technological "solutions" are not always adopted in practice.Our study of the practices, preferences and contexts of Australian DVI practitioners suggests 10 critical considerations for these technologies.We review and evaluate 44 candidate technologies against these considerations and highlight the role of human factors in adoption., Competing Interests: No relevant financial or non-financial competing interests to declare., (© 2022 The Author(s). Published by Taylor & Francis Group on behalf of the Academy of Forensic Science.)
- Published
- 2022
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29. Diagnostic accuracy of D-dimer in patients at high-risk for splanchnic vein thrombosis: A systematic review and meta-analysis.
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Riva N, Attard LM, Vella K, Squizzato A, Gatt A, and Calleja-Agius J
- Abstract
Background: D-dimer is included in the diagnostic algorithm for deep vein thrombosis and pulmonary embolism. However, its role in the diagnosis of splanchnic vein thrombosis (SVT) is still controversial. The aim of this study was to evaluate the diagnostic accuracy of D-dimer for SVT., Methods: We performed a systematic review of the literature with meta-analysis (PROSPERO protocol registration number: CRD42020184300). The electronic databases MEDLINE, EMBASE, and CENTRAL were searched from inception to March 2021 week 4. Studies which evaluated D-dimer accuracy for SVT in any category of patients were selected. The index test was any D-dimer assay; the reference standard was any radiological imaging. The QUADAS-2 checklist was used for the risk of bias assessment. A bivariate random-effects regression model was used to calculate summary estimates of sensitivity and specificity., Results: 12 studies (with a total of 1298 patients) evaluating the accuracy of D-dimer in patients at high risk of SVT (surgical patients, patients with liver cirrhosis or hepatocellular carcinoma) were included. None of the included studies was at low risk of bias. The weighted mean prevalence of SVT was 33.4% (95% CI, 22.5-45.2%, I
2 = 94.8%). D-dimer accuracy was expressed by sensitivity 96% (95% CI, 72-100%); specificity 25% (95% CI, 5-67%); positive likelihood ratio 1.3 (95% CI, 0.9-1.9); negative likelihood ratio 0.16 (95% CI, 0.03-0.84); area under the ROC curve 0.80 (95% CI, 0.76-0.83)., Conclusions: D-dimer seems to have high sensitivity in the diagnosis of patients at high-risk for SVT. However, there is a strong need for more robust evidence on this topic., (Copyright © 2021 Elsevier Ltd. All rights reserved.)- Published
- 2021
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30. Understanding the effectiveness of policy instruments to encourage adoption of farming practices to improve water quality for the Great Barrier Reef.
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Eberhard R, Coggan A, Jarvis D, Hamman E, Taylor B, Baresi U, Vella K, Dean AJ, Deane F, Helmstedt K, and Mayfield H
- Subjects
- Agriculture, Farms, Policy, Ecosystem, Water Quality
- Abstract
Governments in Australia and internationally are experimenting with policy instruments to facilitate the adoption of farming practices with reduced environmental impacts. The Great Barrier Reef (Australia) is one such case, where sustained efforts over 20 years have yielded insufficient progress towards targets to reduce the impacts of agriculture on water quality in downstream marine ecosystems. We present a critical review of policy instruments as implemented in Great Barrier Reef catchments. We catalogue the evolving mix of policy instruments employed in reef programs, and examine evidence of the effectiveness of agricultural extension, financial incentives, and direct regulation of farming practices. There is little robust evidence to assess instrument effectiveness, in part due to the evolving mix of the instruments employed, weak program evaluation and heterogeneity of agricultural enterprises. We identify the need to improve the understanding of instrument fit to landholders and enterprises. We recommend a modelling approach to clarify pathways to impact and guide improved policy evaluation., (Copyright © 2021 Elsevier Ltd. All rights reserved.)
- Published
- 2021
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31. Challenges and opportunities for assisted regional ecosystem adaptation: International experience and implications for adaptation research.
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Vella K, Baresi U, Lockie S, and Taylor B
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- Acclimatization, Climate Change, Ecosystem, Government, Humans, Internationality, Conservation of Natural Resources methods
- Abstract
Maintaining the functional integrity of ecosystems as climate pressures exceed natural rates of adaptation requires new knowledge and new approaches to governance and management. However, research into management interventions to assist regional ecosystem adaptation has generated both scientific and ethical debate. This paper reviews experience to date in order to identify the challenges and opportunities for assisted regional ecosystem adaptation and reflect on the implications for ongoing adaptation research. The review was informed by a database and structured analysis of some 450 reports, peer-reviewed manuscripts and books on participation theory and experience with novel technology development and assisted ecosystem adaptation. We identified five classes of challenges to adaptation research: 1) scientific conflicts and debates over the "facts", 2) social challenges, 3) governance challenges, 4) epistemic challenges, and 5) ontological conflicts. We argue that engagement strategies linked to the multiple objectives of adaptation research provide opportunities for ecosystem adaptation., Competing Interests: No authors have competing interests.
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- 2021
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32. The effect of DOAC-Stop ® on several oral and parenteral anticoagulants.
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Riva N, Vella K, Hickey K, Gatt P, Grima C, Zammit D, Ageno W, Kitchen S, Makris M, and Gatt A
- Subjects
- Administration, Oral, Adsorption, Anticoagulants administration & dosage, Anticoagulants blood, Blood Coagulation Tests methods, Blood Coagulation Tests standards, Humans, Parenteral Nutrition, Anticoagulants chemistry, Charcoal chemistry
- Published
- 2021
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33. Grasping with kirigami shells.
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Yang Y, Vella K, and Holmes DP
- Subjects
- Bioengineering, Biomimetic Materials, Computer Simulation, Equipment Design, Finite Element Analysis, Humans, Magnetic Fields, Mechanical Phenomena, Microtechnology, Polyethylene Terephthalates, Robotics statistics & numerical data, Stimuli Responsive Polymers, Tensile Strength, Hand Strength physiology, Robotics instrumentation, Smart Materials
- Abstract
The ability to grab, hold, and manipulate objects is a vital and fundamental operation in biological and engineering systems. Here, we present a soft gripper using a simple material system that enables precise and rapid grasping, and can be miniaturized, modularized, and remotely actuated. This soft gripper is based on kirigami shells-thin, elastic shells patterned with an array of cuts. The kirigami cut pattern is determined by evaluating the shell's mechanics and geometry, using a combination of experiments, finite element simulations, and theoretical modeling, which enables the gripper design to be both scalable and material independent. We demonstrate that the kirigami shell gripper can be readily integrated with an existing robotic platform or remotely actuated using a magnetic field. The kirigami cut pattern results in a simple unit cell that can be connected together in series, and again in parallel, to create kirigami gripper arrays capable of simultaneously grasping multiple delicate and slippery objects. These soft and lightweight grippers will have applications in robotics, haptics, and biomedical device design., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
- Published
- 2021
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34. Describing the sounds of nature: Using onomatopoeia to classify bird calls for citizen science.
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Vella K, Johnson D, and Roe P
- Subjects
- Acoustics, Animals, Auditory Perception physiology, Australia, Birds physiology, Citizen Science, Sound, Vocalization, Animal physiology
- Abstract
Bird call libraries are difficult to collect yet vital for bio-acoustics studies. A potential solution is citizen science labelling of calls. However, acoustic annotation techniques are still relatively undeveloped and in parallel, citizen science initiatives struggle with maintaining participant engagement, while increasing efficiency and accuracy. This study explores the use of an under-utilised and theoretically engaging and intuitive means of sound categorisation: onomatopoeia. To learn if onomatopoeia was a reliable means of categorisation, an online experiment was conducted. Participants sourced from Amazon mTurk (N = 104) ranked how well twelve onomatopoeic words described acoustic recordings of ten native Australian bird calls. Of the ten bird calls, repeated measures ANOVA revealed that five of these had single descriptors ranked significantly higher than all others, while the remaining calls had multiple descriptors that were rated significantly higher than others. Agreement as assessed by Kendall's W shows that overall, raters agreed regarding the suitability and unsuitability of the descriptors used across all bird calls. Further analysis of the spread of responses using frequency charts confirms this and indicates that agreement on which descriptors were unsuitable was pronounced throughout, and that stronger agreement of suitable singular descriptions was matched with greater rater confidence. This demonstrates that onomatopoeia may be reliably used to classify bird calls by non-expert listeners, adding to the suite of methods used in classification of biological sounds. Interface design implications for acoustic annotation are discussed., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2021
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35. Anticoagulation control with the point-of-care INR: A retrospective pre-/post-analysis.
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Riva N, Meli S, Borg Xuereb C, Vella K, Ageno W, Makris M, and Gatt A
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- Anticoagulants therapeutic use, Humans, International Normalized Ratio, Retrospective Studies, Point-of-Care Systems, Warfarin
- Published
- 2020
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36. Naturalistic evaluation of a sport-themed mental health and wellbeing app aimed at men (MindMax), that incorporates applied video games and gamification.
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Cheng VWS, Davenport T, Johnson D, Vella K, Mitchell J, and Hickie IB
- Abstract
Introduction: While men display lower help-seeking rates than women, there is a lack of mental health interventions targeting men. To address this issue, we developed a smartphone app named MindMax, an Australian Football League (AFL)-themed app containing psychoeducational modules teaching strategies derived from positive psychology and acceptance and commitment therapy. MindMax also incorporates gamification, casual video games, and social connection and is intended to appeal to male Australians interested in AFL. This study reports results from a naturalistic trial intended to investigate whether using MindMax was associated with improved wellbeing, resilience, and help-seeking intentions., Methods: We conducted a naturalistic trial from July 2017 to May 2018, where participants were given access to MindMax to use as they wished, and asked to answer wellbeing surveys at multiple time points. As we employed a customised version of the General Help-Seeking Questionnaire (GHSQ), we conducted an exploratory factor analysis and extracted two factors that we interpreted as 'personal help-seeking' and 'impersonal help-seeking'. Mixed design MANOVAs were conducted with flourishing, resilience, personal help-seeking, impersonal help-seeking, relatedness, and sense of connection (self-group overlap) to the MindMax community to assess change between Day 1-30 and Day 1-60., Results: 313 participants (174/313, 55.6% female; 131/313, 41.9% male) completed the survey at baseline and at least one follow-up survey. We observed significant 30-day and 60-day increases in impersonal help-seeking intentions and sense of connection to the MindMax community, and 60-day increases in flourishing. 30-day increases in sense of connection were highest in our male participants with high base wellbeing, present in our female participants, and not present in our male participants with low base wellbeing. 60-day increases in sense of connection were higher in high-wellbeing participants than in low-wellbeing participants., Discussion/conclusion: Our findings are encouraging as they could be attributed to participants' exposure to MindMax. However, they could also be attributed to other factors that may also have motivated trial participation. Future research can consider investigating more explicitly the role of conformity to masculine norms and how that may affect uptake of mHealth technologies and help-seeking behaviour., Competing Interests: Professor Ian Hickie was an inaugural Commissioner on Australia's National Mental Health Commission (2012–18). He is the Co-Director, Health and Policy at the Brain and Mind Centre (BMC), University of Sydney. The BMC operates an early-intervention youth services at Camperdown under contract to headspace. Professor Hickie has previously led community-based and pharmaceutical industry-supported (Wyeth, Eli Lily, Servier, Pfizer, AstraZeneca) projects focused on the identification and better management of anxiety and depression. He was a member of the Medical Advisory Panel for Medibank Private until October 2017, a Board Member of Psychosis Australia Trust, and a member of Veterans Mental Health Clinical Reference group. He is the Chief Scientific Advisor to, and an equity shareholder in, InnoWell. InnoWell has been formed by the University of Sydney and PwC to deliver the Aus $30M Australian Government-funded ‘Project Synergy’. Project Synergy is a three-year program for the transformation of mental health services through the use of innovative technologies. None of the other authors declare any conflicts of interest., (© 2020 The Authors.)
- Published
- 2020
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37. Teaching an old dog new tricks?
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Gatt A and Vella K
- Subjects
- Fibrin, Fibrin Clot Lysis Time, Fibrinolysis, Humans, Hemorrhagic Disorders, Thrombosis
- Published
- 2019
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38. Gamification in Apps and Technologies for Improving Mental Health and Well-Being: Systematic Review.
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Cheng VWS, Davenport T, Johnson D, Vella K, and Hickie IB
- Abstract
Background: There is little research on the application of gamification to mental health and well-being. Furthermore, usage of gamification-related terminology is inconsistent. Current applications of gamification for health and well-being have also been critiqued for adopting a behaviorist approach that relies on positive reinforcement and extrinsic motivators., Objective: This study aimed to analyze current applications of gamification for mental health and well-being by answering 3 research questions (RQs). RQ1: which gamification elements are most commonly applied to apps and technologies for improving mental health and well-being? RQ2: which mental health and well-being domains are most commonly targeted by these gamified apps and technologies? RQ3: what reasons do researchers give for applying gamification to these apps and technologies? A systematic review of the literature was conducted to answer these questions., Methods: We searched ACM Digital Library, CINAHL, Cochrane Library, EMBASE, IEEE Explore, JMIR, MEDLINE, PsycINFO, PubMed, ScienceDirect, Scopus, and Web of Science for qualifying papers published between the years 2013 and 2018. To answer RQ1 and RQ2, papers were coded for gamification elements and mental health and well-being domains according to existing taxonomies in the game studies and medical literature. During the coding process, it was necessary to adapt our coding frame and revise these taxonomies. Thematic analysis was conducted to answer RQ3., Results: The search and screening process identified 70 qualifying papers that collectively reported on 50 apps and technologies. The most commonly observed gamification elements were levels or progress feedback, points or scoring, rewards or prizes, narrative or theme, personalization, and customization; the least commonly observed elements were artificial assistance, unlockable content, social cooperation, exploratory or open-world approach, artificial challenge, and randomness. The most commonly observed mental health and well-being domains were anxiety disorders and well-being, whereas the least commonly observed domains were conduct disorder and bipolar disorders. Researchers' justification for applying gamification to improving mental health and well-being was coded in 59% (41/70) of the papers and was broadly divided into 2 themes: (1) promoting engagement and (2) enhancing an intervention's intended effects., Conclusions: Our findings suggest that the current application of gamification to apps and technologies for improving mental health and well-being does not align with the trend of positive reinforcement critiqued in the greater health and well-being literature. We also observed overlap between the most commonly used gamification techniques and existing behavior change frameworks. Results also suggest that the application of gamification is not driven by health behavior change theory, and that many researchers may treat gamification as a black box without consideration for its underlying mechanisms. We call for the inclusion of more comprehensive and explicit descriptions of how gamification is applied and the standardization of applied games terminology within and across fields., (©Vanessa Wan Sze Cheng, Tracey Davenport, Daniel Johnson, Kellie Vella, Ian B Hickie. Originally published in JMIR Mental Health (http://mental.jmir.org), 26.06.2019.)
- Published
- 2019
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39. Reporting preclinical anesthesia study (REPEAT): Evaluating the quality of reporting in the preclinical anesthesiology literature.
- Author
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Fergusson DA, Avey MT, Barron CC, Bocock M, Biefer KE, Boet S, Bourque SL, Conic I, Chen K, Dong YY, Fox GM, George RB, Goldenberg NM, Gragasin FS, Harsha P, Hong PJ, James TE, Larrigan SM, MacNeil JL, Manuel CA, Maximos S, Mazer D, Mittal R, McGinn R, Nguyen LH, Patel A, Richebé P, Saha TK, Steinberg BE, Sampson SD, Stewart DJ, Syed S, Vella K, Wesch NL, and Lalu MM
- Subjects
- Analgesics therapeutic use, Animals, Databases, Factual, Guidelines as Topic, Pain drug therapy, Drug Evaluation, Preclinical standards, Research Report standards
- Abstract
Poor reporting quality may contribute to irreproducibility of results and failed 'bench-to-bedside' translation. Consequently, guidelines have been developed to improve the complete and transparent reporting of in vivo preclinical studies. To examine the impact of such guidelines on core methodological and analytical reporting items in the preclinical anesthesiology literature, we sampled a cohort of studies. Preclinical in vivo studies published in Anesthesiology, Anesthesia & Analgesia, Anaesthesia, and the British Journal of Anaesthesia (2008-2009, 2014-2016) were identified. Data was extracted independently and in duplicate. Reporting completeness was assessed using the National Institutes of Health Principles and Guidelines for Reporting Preclinical Research. Risk ratios were used for comparative analyses. Of 7615 screened articles, 604 met our inclusion criteria and included experiments reporting on 52 490 animals. The most common topic of investigation was pain and analgesia (30%), rodents were most frequently used (77%), and studies were most commonly conducted in the United States (36%). Use of preclinical reporting guidelines was listed in 10% of applicable articles. A minority of studies fully reported on replicates (0.3%), randomization (10%), blinding (12%), sample-size estimation (3%), and inclusion/exclusion criteria (5%). Statistics were well reported (81%). Comparative analysis demonstrated few differences in reporting rigor between journals, including those that endorsed reporting guidelines. Principal items of study design were infrequently reported, with few differences between journals. Methods to improve implementation and adherence to community-based reporting guidelines may be necessary to increase transparent and consistent reporting in the preclinical anesthesiology literature., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
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40. Fibrinogen measurement in liver disease: validation of the functional fibrinogen thromboelastography assay and a novel mathematical predictive model.
- Author
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Rizzo K, Vella K, Zammit D, Gatt P, Grima C, Inguanez MB, Gerada J, Ellul P, Vassallo M, Azzopardi N, Pocock J, and Gatt A
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Liver Diseases pathology, Male, Middle Aged, Fibrinogen metabolism, Liver Diseases blood, Models, Biological, Thrombelastography
- Abstract
Background: Fibrinogen is produced in the liver and tends to be reduced in liver cirrhosis. Quantitative and qualitative tests exist to measure fibrinogen. We aimed to validate the functional fibrinogen thromboelastography assay (FF-TEG) and propose a new model to estimate fibrinogen levels via the Clauss method (Clauss) using data from a prothrombin time-derived fibrinogen assay (PT-Fg) in patients with liver cirrhosis., Materials and Methods: Clauss, PT-Fg, fibrinogen antigen (Fib-Ag) and FF-TEG were studied in 55 patients with liver cirrhosis (26 with Child-Turcotte-Pugh [CTP]-A disease, 14 with CTP-B and 15 CTP-C) and 20 healthy individuals., Results: The results of all four assays correlated strongly with each other, but gave significantly different mean levels in all cohorts. PT-Fg gave the highest levels whereas the Clauss gave the lowest levels. The FF-TEG performed well with results which were in between the Clauss and the PT-Fg. Significant differences were only observed between CTP-A and CTP-C for the Clauss, PT-Fg and Fib-Ag but not functional fibrinogen level. We devised a simple linear regression model in order to estimate Clauss from the PT-Fg., Discussion: The results of the FF-TEG correlate well with those of routine fibrinogen assays in patients with liver cirrhosis. However, the FF-TEG assay does not discriminate between early and late stages of disease, pointing to a preserved fibrin clot strength in cirrhosis. Through linear regression models, fibrinogen levels can be accurately estimated using the Clauss method based on fibrinogen levels obtained in the cheaper PT-Fg.
- Published
- 2019
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41. An App That Incorporates Gamification, Mini-Games, and Social Connection to Improve Men's Mental Health and Well-Being (MindMax): Participatory Design Process.
- Author
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Cheng VWS, Davenport TA, Johnson D, Vella K, Mitchell J, and Hickie IB
- Abstract
Background: Men have different mental health needs as compared with women, and women make up the primary audience of most digital mental health interventions. An Australian football-themed (specifically Australian Football League, AFL) app named MindMax incorporating psychoeducation, gamification, mini-games, and social connection was developed in an effort to address this issue., Objective: The aim of this study was to identify the best way to structure and present MindMax, an app that aims to deliver psychoeducational modules, and create a Web-based community centering on well-being, AFL, and video games for men aged 16 to 35 years who are interested in AFL or video games., Methods: We conducted 6 participatory design (PD) workshops with people aged 16 to 35 years in 3 cities in Australia, to identify the best way to present MindMax, and contracted a digital development agency to develop MindMax. We then iteratively tested MindMax prototypes with 15 user experience testing interviews across 3 separate time points: 2 before app launch and 1 after app launch., Results: A total of 40 individuals (25 male and 15 female) participated in the PD workshops, and a total of 15 individuals (10 male and 5 female) participated in user experience interviews. Broadly, participants expressed a preference for activities requiring active engagement that practiced useful skills. They were also sensitive to how content was presented and wanted the ability to customize their own app experience. Although participants agreed that social motivations were important for engagement with an app, they recommended not to mimic existing social networks., Conclusions: In basing itself strongly within the AFL subculture and by incorporating gamification as well as mini-games, MindMax aimed to tackle mental health help-seeking barriers for people who enjoy AFL or video games, with a particular emphasis on men, and to provide psychoeducation on strategies to increase mental health and well-being. If MindMax is successful, this would indicate that generalizing this approach to other traditional sporting codes and even competitive video gaming leagues (esports) would be fruitful., (©Vanessa Wan Sze Cheng, Tracey A Davenport, Daniel Johnson, Kellie Vella, Jo Mitchell, Ian B Hickie. Originally published in JMIR Mental Health (http://mental.jmir.org), 19.11.2018.)
- Published
- 2018
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42. Biomarkers for the diagnosis of venous thromboembolism: D-dimer, thrombin generation, procoagulant phospholipid and soluble P-selectin.
- Author
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Riva N, Vella K, Hickey K, Bertù L, Zammit D, Spiteri S, Kitchen S, Makris M, Ageno W, and Gatt A
- Subjects
- Adult, Aged, Biomarkers blood, Computed Tomography Angiography, Female, Humans, Male, Malta, Middle Aged, Perfusion Imaging, Predictive Value of Tests, Reproducibility of Results, Ultrasonography, Venous Thromboembolism diagnostic imaging, Blood Coagulation, Blood Coagulation Tests, Fibrin Fibrinogen Degradation Products analysis, P-Selectin blood, Phospholipids blood, Thrombin metabolism, Venous Thromboembolism blood, Venous Thromboembolism diagnosis
- Abstract
Background: The diagnostic algorithm for venous thromboembolism (VTE) currently involves a composite of pre-test probability, D-dimer and imaging. Other laboratory tests, however, may assist in the identification of patients with VTE., Aim: To assess the accuracy of different coagulation tests (D-dimer, thrombin generation, phospholipid-dependent (PPL) clotting time, soluble P-selectin (sP-selectin)) as biomarkers of acute VTE., Methods: Random samples arriving at the Coagulation Laboratory at Mater Dei Hospital (Msida, Malta) from the Accident and Emergency Department with a request for D-dimer measurement were collected between August 2015 and February 2016. The following tests were performed: Innovance D-dimer (Siemens Healthcare Diagnostics), HemosIL D-dimer HS (Instrumentation Laboratory), thrombin generation (using the calibrated automated thrombogram), STA Procoag PPL (Diagnostica Stago) and sP-selectin (Affymetrix; eBioscience). VTE was objectively confirmed by compression ultrasonography, CT pulmonary angiography or ventilation/perfusion lung scan., Results: 100 samples were collected (33 with VTE). A strong positive linear correlation was found between the two D-dimer tests (r=0.97, p<0.001). Patients with VTE showed significantly higher sP-selectin concentrations compared with patients without VTE (75.7 ng/mL vs 53.0 ng/mL, p<0.001). In the random forest plot, the two D-dimer assays showed the highest variable importance, followed by sP-selectin. A sP-selectin cut-off of 74.8 ng/mL was associated with 72.7% sensitivity and 78.2% specificity for acute VTE in our cohort., Conclusion: Our results confirmed D-dimer as the main biomarker of VTE and speculated a role for sP-selectin. The impact of thrombin generation was limited and no role emerged for the PPL clotting time. These observations need to be confirmed in large management studies., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2018
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43. Avoiding Implementation Failure in Catchment Landscapes: A Case Study in Governance of the Great Barrier Reef.
- Author
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Dale AP, Vella K, Gooch M, Potts R, Pressey RL, Brodie J, and Eberhard R
- Subjects
- Agriculture organization & administration, Conservation of Natural Resources legislation & jurisprudence, Conservation of Natural Resources trends, Coral Reefs, Decision Making, Environmental Policy legislation & jurisprudence, Forests, Queensland, Conservation of Natural Resources methods, Environmental Policy trends, Government Regulation, Rivers chemistry, Water Quality standards
- Abstract
Water quality outcomes affecting Australia's Great Barrier Reef (GBR) are governed by multi-level and multi-party decision-making that influences forested and agricultural landscapes. With international concern about the GBR's declining ecological health, this paper identifies and focuses on implementation failure (primarily at catchment scale) as a systemic risk within the overall GBR governance system. There has been limited integrated analysis of the full suite of governance subdomains that often envelop defined policies, programs and delivery activities that influence water quality in the GBR. We consider how the implementation of separate purpose-specific policies and programs at catchment scale operate against well-known, robust design concepts for integrated catchment governance. We find design concerns within ten important governance subdomains that operate within GBR catchments. At a whole-of-GBR scale, we find a weak policy focus on strengthening these delivery-oriented subdomains and on effort integration across these subdomains within catchments. These governance problems when combined may contribute to failure in the implementation of major national, state and local government policies focused on improving water quality in the GBR, a lesson relevant to landscapes globally.
- Published
- 2018
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44. Risk analysis of the governance system affecting outcomes in the Great Barrier Reef.
- Author
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Dale AP, Vella K, Pressey RL, Brodie J, Gooch M, Potts R, and Eberhard R
- Subjects
- Australia, Government, Queensland, Water Quality, Conservation of Natural Resources methods, Risk Assessment methods
- Abstract
The state and trend of the Great Barrier Reef's (GBR's) ecological health remains problematic, influencing United Nations Educational, Scientific and Cultural Organization (UNESCO) statements regarding GBR governance. While UNESCO's concerns triggered separate strategic assessments by the Australian and Queensland governments, there has been no independent and integrated review of the key risks within the overall system of governance influencing GBR outcomes. As a case study of international significance, this paper applies Governance Systems Analysis (GSA), a novel analytical framework that identifies the governance themes, domains and subdomains most likely to influence environmental and socio-economic outcomes in complex natural systems. This GBR-focussed application of GSA identifies governance subdomains that present high, medium, or low risk of failure to produce positive outcomes for the Reef. This enabled us to determine that three "whole of system" governance problems could undermine GBR outcomes. First, we stress the integrative importance of the Long Term Sustainability Plan (LTSP) Subdomain. Sponsored by the Australian and Queensland governments, this subdomain concerns the primary institutional arrangements for coordinated GBR planning and delivery, but due to its recent emergence, it faces several internal governance challenges. Second, we find a major risk of implementation failure in the achievement of GBR water quality actions due to a lack of system-wide focus on building strong and stable delivery systems at catchment scale. Finally, we conclude that the LTSP Subdomain currently has too limited a mandate/capacity to influence several high-risk subdomains that have not been, but must be more strongly aligned with Reef management (e.g. the Greenhouse Gas Emission Management Subdomain). Our analysis enables exploration of governance system reforms needed to address environmental trends in the GBR and reflects on the potential application of GSA in other complex land and sea-scapes across the globe., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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45. Surfactant-associated bacteria in the near-surface layer of the ocean.
- Author
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Kurata N, Vella K, Hamilton B, Shivji M, Soloviev A, Matt S, Tartar A, and Perrie W
- Subjects
- Florida, Bacteria metabolism, Oceans and Seas, Surface-Active Agents metabolism
- Abstract
Certain marine bacteria found in the near-surface layer of the ocean are expected to play important roles in the production and decay of surface active materials; however, the details of these processes are still unclear. Here we provide evidence supporting connection between the presence of surfactant-associated bacteria in the near-surface layer of the ocean, slicks on the sea surface, and a distinctive feature in the synthetic aperture radar (SAR) imagery of the sea surface. From DNA analyses of the in situ samples using pyrosequencing technology, we found the highest abundance of surfactant-associated bacterial taxa in the near-surface layer below the slick. Our study suggests that production of surfactants by marine bacteria takes place in the organic-rich areas of the water column. Produced surfactants can then be transported to the sea surface and form slicks when certain physical conditions are met. This finding has potential applications in monitoring organic materials in the water column using remote sensing techniques. Identifying a connection between marine bacteria and production of natural surfactants may provide a better understanding of the global picture of biophysical processes at the boundary between the ocean and atmosphere, air-sea exchange of greenhouse gases, and production of climate-active marine aerosols.
- Published
- 2016
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46. Impaired sinoatrial node function and increased susceptibility to atrial fibrillation in mice lacking natriuretic peptide receptor C.
- Author
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Egom EE, Vella K, Hua R, Jansen HJ, Moghtadaei M, Polina I, Bogachev O, Hurnik R, Mackasey M, Rafferty S, Ray G, and Rose RA
- Subjects
- Action Potentials, Animals, Cells, Cultured, Collagen metabolism, Male, Mice, Mice, Inbred C57BL, Myocytes, Cardiac metabolism, Myocytes, Cardiac physiology, Receptors, Atrial Natriuretic Factor metabolism, Sinoatrial Node physiopathology, Atrial Fibrillation genetics, Atrial Fibrillation metabolism, Receptors, Atrial Natriuretic Factor genetics, Sinoatrial Node metabolism
- Abstract
Natriuretic peptides (NPs) are critical regulators of the cardiovascular system that are currently viewed as possible therapeutic targets for the treatment of heart disease. Recent work demonstrates potent NP effects on cardiac electrophysiology, including in the sinoatrial node (SAN) and atria. NPs elicit their effects via three NP receptors (NPR-A, NPR-B and NPR-C). Among these receptors, NPR-C is poorly understood. Accordingly, the goal of this study was to determine the effects of NPR-C ablation on cardiac structure and arrhythmogenesis. Cardiac structure and function were assessed in wild-type (NPR-C(+/+)) and NPR-C knockout (NPR-C(-/-)) mice using echocardiography, intracardiac programmed stimulation, patch clamping, high-resolution optical mapping, quantitative polymerase chain reaction and histology. These studies demonstrate that NPR-C(-/-) mice display SAN dysfunction, as indicated by a prolongation (30%) of corrected SAN recovery time, as well as an increased susceptibility to atrial fibrillation (6% in NPR-C(+/+) vs. 47% in NPR-C(-/-)). There were no differences in SAN or atrial action potential morphology in NPR-C(-/-) mice; however, increased atrial arrhythmogenesis in NPR-C(-/-) mice was associated with reductions in SAN (20%) and atrial (15%) conduction velocity, as well as increases in expression and deposition of collagen in the atrial myocardium. No differences were seen in ventricular arrhythmogenesis or fibrosis in NPR-C(-/-) mice. This study demonstrates that loss of NPR-C results in SAN dysfunction and increased susceptibility to atrial arrhythmias in association with structural remodelling and fibrosis in the atrial myocardium. These findings indicate a critical protective role for NPR-C in the heart., (© 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.)
- Published
- 2015
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47. The selective loss of the type 2 iodothyronine deiodinase in mouse thyrotrophs increases basal TSH but blunts the thyrotropin response to hypothyroidism.
- Author
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Luongo C, Martin C, Vella K, Marsili A, Ambrosio R, Dentice M, Harney JW, Salvatore D, Zavacki AM, and Larsen PR
- Subjects
- Animals, Animals, Newborn, Cerebral Cortex enzymology, Female, Gene Silencing, Iodide Peroxidase genetics, Male, Mice, Knockout, Thyroid Hormones, Iodothyronine Deiodinase Type II, Hypothyroidism blood, Iodide Peroxidase metabolism, Thyrotrophs enzymology, Thyrotropin blood
- Abstract
The type 2 iodothyronine deiodinase (D2) is essential for feedback regulation of TSH by T4. We genetically inactivated in vivo D2 in thyrotrophs using a mouse model of Cga-driven cre recombinase. Pituitary D2 activity was reduced 90% in the Cga-cre D2 knockout (KO) mice compared with control Dio2(fl/fl) mice. There was no growth or reproductive phenotype. Basal TSH levels were increased 1.5- to 1.8-fold, but serum T4 and T3 were not different from the controls in adult mice. In hypothyroid adult mice, suppression of TSH by T4, but not T3, was impaired. Despite mild basal TSH elevation, the TSH increase in response to hypothyroidism was 4-fold reduced in the Cga-cre D2KO compared with control mice despite an identical level of pituitary TSH α- and β-subunit mRNAs. In neonatal Cga-cre D2KO mice, TSH was also 2-fold higher than in the controls, but serum T4 was elevated. Despite a constant TSH, serum T4 increased 2-3-fold between postnatal day (P) 5 and P15 in both genotypes. The pituitary, but not cerebrocortical, D2 activity was markedly elevated in P5 mice decreasing towards adult levels by P17. In conclusion, a congenital severe reduction of thyrotroph D2 causes a major impairment of the TSH response to hypothyroidism. This would be deleterious to the compensatory adaptation of the thyroid gland to iodine deficiency.
- Published
- 2015
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48. Comparison of assessments of fitness to drive for people with dementia.
- Author
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Vella K and Lincoln NB
- Subjects
- Aged, Aged, 80 and over, Automobile Driving psychology, Dementia psychology, Female, Humans, Male, Middle Aged, Neuropsychological Tests, Automobile Driver Examination, Automobile Driving standards, Dementia diagnosis
- Abstract
Cognitive tests are used to inform recommendations about the fitness to drive of people with dementia. The Rookwood Driving Battery (RDB) and Dementia Drivers' Screening Assessment (DDSA) are neuropsychological batteries designed to assist in this process. The aim was to assess the concordance between the classifications (pass/fail) of the RDB and DDSA in individuals with dementia, and to compare any discordant classifications against on-road driving ability. Participants were identified by community mental health teams and psychiatrists. Twenty four participants were recruited. The mean age was 74.1 (SD 8.9) years and 18 (75%) were men. Each participant was assessed on the RDB and DDSA in an order determined by random allocation. Those with discrepant results also had an on-road assessment. The agreement between the tests was 54% using a cut-off of > 6 on the RDB, and 75% using the cut-off to > 10 on the RDB. Three participants with discrepant results agreed to be assessed on the road and all were found to be safe to drive. The findings suggested that there was poor concurrent validity between the RDB and DDSA. This raises questions about the choice of assessments in making clinical recommendations about fitness to drive in people with dementia.
- Published
- 2014
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49. Natriuretic peptides regulate heart rate and sinoatrial node function by activating multiple natriuretic peptide receptors.
- Author
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Azer J, Hua R, Vella K, and Rose RA
- Subjects
- Adrenergic beta-Agonists pharmacology, Animals, Atrial Natriuretic Factor pharmacology, Cells, Cultured, Heart drug effects, In Vitro Techniques, Isoproterenol pharmacology, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Myocytes, Cardiac drug effects, Myocytes, Cardiac metabolism, Myocytes, Cardiac physiology, Natriuretic Peptide, Brain pharmacology, Natriuretic Peptide, C-Type pharmacology, Peptide Fragments pharmacology, Receptors, Atrial Natriuretic Factor agonists, Receptors, Atrial Natriuretic Factor antagonists & inhibitors, Receptors, Atrial Natriuretic Factor metabolism, Sinoatrial Node drug effects, Tetrahydroisoquinolines pharmacology, Heart Rate drug effects, Natriuretic Peptide, Brain physiology, Natriuretic Peptide, C-Type physiology, Sinoatrial Node physiology
- Abstract
Natriuretic peptides, including BNP and CNP, elicit their effects via two guanylyl cyclase-linked receptors denoted NPR-A and NPR-B as well as a third receptor, NPR-C. The relative contributions of these receptors to the overall effects of NPs on heart rate (HR) and sinoatrial node (SAN) function are very poorly understood. The effects of BNP and CNP (10-500 nM) on HR and SAN myocyte spontaneous action potential (AP) firing were studied using wildtype mice and mice lacking functional NPR-C receptors (NPR-C(-/-)). In basal conditions and 10 nM doses of the β-adrenergic receptor (β-AR) agonist isoproterenol (ISO) BNP and CNP increased HR and AP firing in SAN myocytes. The NPR-C selective agonist cANF (10-500 nM) had no effects in basal conditions, but decreased HR and SAN AP frequency in the presence of ISO. These effects of cANF were completely absent in NPR-C(-/-) mice. Strikingly, in the presence of 1 μM doses of ISO, BNP and CNP switched to causing decreases in HR and SAN AP frequency. These decreases were not as large as those elicited by cANF and were absent in NPR-C(-/-) hearts, where BNP instead elicited a further increase in HR. Inhibition of NPR-A with A71915, in the presence of 1 μM ISO, enabled BNP to signal exclusively through NPR-C and to decrease HR as effectively as cANF. Together these data demonstrate that BNP and CNP affect HR and SAN function by activating multiple receptor subtypes. NPR-A/B mediate increases in HR and SAN function, but these effects are opposed by NPR-C, which plays an increasingly important signaling role in the presence of β-AR stimulation., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
- Full Text
- View/download PDF
50. A prospective study of cognitive tests to predict performance on a standardised road test in people with dementia.
- Author
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Lincoln NB, Taylor JL, Vella K, Bouman WP, and Radford KA
- Subjects
- Aged, Aged, 80 and over, Executive Function, Female, Humans, Logistic Models, Male, Memory, Middle Aged, Predictive Value of Tests, Prospective Studies, Visual Perception, Automobile Driver Examination, Cognition, Dementia psychology, Mental Competency standards, Neuropsychological Tests standards
- Abstract
Objective: Previous work by Lincoln and colleagues produced a cognitive test battery for predicting safety to drive in people with dementia. The aim was to check the accuracy of this battery and assess whether it could be improved by shortening it, including additional cognitive tests, and a measure of previous driving., Methods: Participants with dementia, who were driving, were recruited. They were assessed on cognitive tests including measures of concentration, executive function, visuospatial perception, verbal recognition memory, and speed of information processing. Patients were then assessed on the Nottingham Neurological Driving Assessment (NNDA) by an approved driving instructor (ADI), blind to cognitive test results., Results: Seventy-five patients were recruited and completed the cognitive tests. Of these, 65 were assessed on the road. These participants were aged 59-88 (mean = 75.2, SD = 6.8) and 49 were men. Time driving varied from 19 to 73 years (mean = 52.5, SD = 10.0). Thirteen participants were unsafe and 52 safe to drive. Using a cut-off of > 0 to indicate safety to drive, the original predictive equations correctly classified 48 (76.2%) of 63 participants with complete data. Logistic regression including additional tests reduced misclassifications., Conclusions: A lower proportion of participants were found to be unsafe on the road than in previous studies. Nevertheless, the previously identified equation predicted safety to drive in most patients. Including additional tests reduced the misclassification rate but requires independent validation. We suggest that the cognitive test battery might be used in clinical practice to identify patients with dementia who would benefit from on-road assessment.
- Published
- 2010
- Full Text
- View/download PDF
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