sunil nair - Academia.edu (original) (raw)

Papers by sunil nair

Research paper thumbnail of Quantifying Uncertainty in Safety Cases Using Evidential Reasoning

Lecture Notes in Computer Science, 2014

Research paper thumbnail of Classification, Structuring, and Assessment of Evidence for Safety -- A Systematic Literature Review

2013 IEEE Sixth International Conference on Software Testing, Verification and Validation, 2013

ABSTRACT Safety assurance and certification are amongst the most expensive and time-consuming tas... more ABSTRACT Safety assurance and certification are amongst the most expensive and time-consuming tasks in the development of safety-critical systems. Demonstration of compliance with safety standards involves providing evidence that the standards' safety criteria are met. To handle large collections of evidence effectively, safety professionals need knowledge of how to classify different types of evidence, how to structure the evidence, and how to assess it. This paper takes a step towards developing such a body of knowledge by conducting a Systematic Literature Review (SLR). Specifically, the SLR identifies and classifies the information and artefacts considered as evidence for safety, examines existing techniques for evidence structuring and assessment, and summarizes the challenges noted in the literature in relation to safety evidence. The paper, to our knowledge, is the first systematic review on the topic of safety evidence. The results we present are particularly relevant to practitioners seeking to better understand the evidence requirements for safety certification, as well as to researchers conducting research in this area.

Research paper thumbnail of A review of traceability research at the requirements engineering conference<sup>re@21</sup>

2013 21st IEEE International Requirements Engineering Conference (RE), 2013

ABSTRACT Traceability between development artefacts and mainly from and to requirements plays a m... more ABSTRACT Traceability between development artefacts and mainly from and to requirements plays a major role in system lifecycle, supporting activities such as system validation, change impact analysis, and regulation compliance. Many researchers have been working on this topic and have published their work throughout the editions of the Requirements Engineering Conference. This paper aims to analyse the research on traceability published in the past 20 years of this conference and to provide insights into its contribution to the traceability area. We have selected and reviewed 70 papers in the proceedings of the conference and summarised several aspects of traceability that have been addressed and by whom. The paper also discusses the evolution of the topic at the conference, compares the results with those reported in other publications, and proposes aspects on which further research should be conducted.

Research paper thumbnail of Safety Evidence Traceability: Problem Analysis and Model

Lecture Notes in Computer Science, 2014

Research paper thumbnail of Towards a Model-Based Evolutionary Chain of Evidence for Compliance with Safety Standards

Lecture Notes in Computer Science, 2012

Research paper thumbnail of An extended systematic literature review on provision of evidence for safety certification

Information and Software Technology, 2014

Research paper thumbnail of Detection of the cardiovascular complications of thalassemia by echocardiography

Annals of the New York Academy of Sciences, 2010

The thalassemia syndromes are associated with cardiovascular complications, which differ with the... more The thalassemia syndromes are associated with cardiovascular complications, which differ with the varying phenotypes encountered. The well-recognized paradigm of heart failure induced by myocardial iron overload, in thalassemia major (TM), has now been joined by pulmonary arterial hypertension (mostly seen in thalassemia intermedia) among other more subtle disorders of the cardiovascular system, including endothelial dysfunction. Cardiovascular magnetic resonance (T2*) has allowed cardiac iron load to be quantified noninvasively, and the routine measurement of T2* has been associated with a marked improvement in the outlook for patients with TM, in particular. Echocardiography remains an indispensable tool in the cardiovascular assessment of patients, it provides many insights into cardiovascular function, and its use allows improved management of patients. It is particularly suited to assess diastolic function, diagnose intracardiac masses (usually thrombus), and assess right ventricular function and pulmonary pressure.

Research paper thumbnail of Myocardial Iron Loading in Patients with Thalassemia Major on Deferoxamine Chelation

Journal of Cardiovascular Magnetic Resonance, 2006

Heart failure secondary to myocardial iron loading remains the leading cause of death in thalasse... more Heart failure secondary to myocardial iron loading remains the leading cause of death in thalassemia major (TM). We used cardiovascular magnetic resonance (CMR) to assess the prevalence of myocardial iron overload and ventricular dysfunction in a large cohort of TM patients maintained on conventional chelation treatment with deferoxamine. A mobile CMR scanner was transported from London, UK, to Sardinia, Italy where 167 TM patients were assessed for myocardial iron loading, B-natriuretic peptide (BNP), and ferritin. In patients with myocardial iron loading CMR assessments of ventricular function were also made. Myocardial iron loading (T2* &lt; 20 ms) was present in 108 (65%) patients, which was severe (T2* &lt; 8 ms) in 22 (13%). Impaired (&lt; 56%) left ventricular (LV) ejection fraction (EF) was present in 5%, 20% and 62% of patients with mild, moderate or severe iron loading. Increasing myocardial iron was related to impaired LVEF (Rs = 0.57, p &lt; 0.001), weakly related to serum ferritin (Rs = -0.34, p &lt; 0.001), and not related to liver iron (Rs = 0.11, p = 0.26). BNP was weakly related to myocardial iron (Rs = -0.35, p &lt; 0.001) and was abnormal in only 5 patients. Myocardial siderosis was found in two-thirds of thalassemia major patients on maintenance deferoxamine treatment. This was combined with a high prevalence of impaired LV function, the severity of which tracked the severity of iron deposition. BNP was not useful to assess myocardial siderosis.

Research paper thumbnail of Effects of combined deferiprone with deferoxamine on right ventricular function in thalassaemia major

Journal of Cardiovascular Magnetic Resonance, 2012

Research paper thumbnail of Combined chelation therapy in thalassemia major for the treatment of severe myocardial siderosis with left ventricular dysfunction

Journal of Cardiovascular Magnetic Resonance, 2008

Research paper thumbnail of A Randomized, Placebo-Controlled, Double-Blind Trial of the Effect of Combined Therapy With Deferoxamine and Deferiprone on Myocardial Iron in Thalassemia Major Using Cardiovascular Magnetic Resonance

Circulation, 2007

Methods and Results— Myocardial iron loading was assessed with the use of myocardial T2* cardiova... more Methods and Results— Myocardial iron loading was assessed with the use of myocardial T2* cardiovascular magnetic resonance in 167 patients with thalassemia major receiving standard maintenance chelation monotherapy with subcutaneous deferoxamine. Of these patients, ...

Research paper thumbnail of Quantifying Uncertainty in Safety Cases Using Evidential Reasoning

Lecture Notes in Computer Science, 2014

Research paper thumbnail of Classification, Structuring, and Assessment of Evidence for Safety -- A Systematic Literature Review

2013 IEEE Sixth International Conference on Software Testing, Verification and Validation, 2013

ABSTRACT Safety assurance and certification are amongst the most expensive and time-consuming tas... more ABSTRACT Safety assurance and certification are amongst the most expensive and time-consuming tasks in the development of safety-critical systems. Demonstration of compliance with safety standards involves providing evidence that the standards&#39; safety criteria are met. To handle large collections of evidence effectively, safety professionals need knowledge of how to classify different types of evidence, how to structure the evidence, and how to assess it. This paper takes a step towards developing such a body of knowledge by conducting a Systematic Literature Review (SLR). Specifically, the SLR identifies and classifies the information and artefacts considered as evidence for safety, examines existing techniques for evidence structuring and assessment, and summarizes the challenges noted in the literature in relation to safety evidence. The paper, to our knowledge, is the first systematic review on the topic of safety evidence. The results we present are particularly relevant to practitioners seeking to better understand the evidence requirements for safety certification, as well as to researchers conducting research in this area.

Research paper thumbnail of A review of traceability research at the requirements engineering conference<sup>re@21</sup>

2013 21st IEEE International Requirements Engineering Conference (RE), 2013

ABSTRACT Traceability between development artefacts and mainly from and to requirements plays a m... more ABSTRACT Traceability between development artefacts and mainly from and to requirements plays a major role in system lifecycle, supporting activities such as system validation, change impact analysis, and regulation compliance. Many researchers have been working on this topic and have published their work throughout the editions of the Requirements Engineering Conference. This paper aims to analyse the research on traceability published in the past 20 years of this conference and to provide insights into its contribution to the traceability area. We have selected and reviewed 70 papers in the proceedings of the conference and summarised several aspects of traceability that have been addressed and by whom. The paper also discusses the evolution of the topic at the conference, compares the results with those reported in other publications, and proposes aspects on which further research should be conducted.

Research paper thumbnail of Safety Evidence Traceability: Problem Analysis and Model

Lecture Notes in Computer Science, 2014

Research paper thumbnail of Towards a Model-Based Evolutionary Chain of Evidence for Compliance with Safety Standards

Lecture Notes in Computer Science, 2012

Research paper thumbnail of An extended systematic literature review on provision of evidence for safety certification

Information and Software Technology, 2014

Research paper thumbnail of Detection of the cardiovascular complications of thalassemia by echocardiography

Annals of the New York Academy of Sciences, 2010

The thalassemia syndromes are associated with cardiovascular complications, which differ with the... more The thalassemia syndromes are associated with cardiovascular complications, which differ with the varying phenotypes encountered. The well-recognized paradigm of heart failure induced by myocardial iron overload, in thalassemia major (TM), has now been joined by pulmonary arterial hypertension (mostly seen in thalassemia intermedia) among other more subtle disorders of the cardiovascular system, including endothelial dysfunction. Cardiovascular magnetic resonance (T2*) has allowed cardiac iron load to be quantified noninvasively, and the routine measurement of T2* has been associated with a marked improvement in the outlook for patients with TM, in particular. Echocardiography remains an indispensable tool in the cardiovascular assessment of patients, it provides many insights into cardiovascular function, and its use allows improved management of patients. It is particularly suited to assess diastolic function, diagnose intracardiac masses (usually thrombus), and assess right ventricular function and pulmonary pressure.

Research paper thumbnail of Myocardial Iron Loading in Patients with Thalassemia Major on Deferoxamine Chelation

Journal of Cardiovascular Magnetic Resonance, 2006

Heart failure secondary to myocardial iron loading remains the leading cause of death in thalasse... more Heart failure secondary to myocardial iron loading remains the leading cause of death in thalassemia major (TM). We used cardiovascular magnetic resonance (CMR) to assess the prevalence of myocardial iron overload and ventricular dysfunction in a large cohort of TM patients maintained on conventional chelation treatment with deferoxamine. A mobile CMR scanner was transported from London, UK, to Sardinia, Italy where 167 TM patients were assessed for myocardial iron loading, B-natriuretic peptide (BNP), and ferritin. In patients with myocardial iron loading CMR assessments of ventricular function were also made. Myocardial iron loading (T2* &lt; 20 ms) was present in 108 (65%) patients, which was severe (T2* &lt; 8 ms) in 22 (13%). Impaired (&lt; 56%) left ventricular (LV) ejection fraction (EF) was present in 5%, 20% and 62% of patients with mild, moderate or severe iron loading. Increasing myocardial iron was related to impaired LVEF (Rs = 0.57, p &lt; 0.001), weakly related to serum ferritin (Rs = -0.34, p &lt; 0.001), and not related to liver iron (Rs = 0.11, p = 0.26). BNP was weakly related to myocardial iron (Rs = -0.35, p &lt; 0.001) and was abnormal in only 5 patients. Myocardial siderosis was found in two-thirds of thalassemia major patients on maintenance deferoxamine treatment. This was combined with a high prevalence of impaired LV function, the severity of which tracked the severity of iron deposition. BNP was not useful to assess myocardial siderosis.

Research paper thumbnail of Effects of combined deferiprone with deferoxamine on right ventricular function in thalassaemia major

Journal of Cardiovascular Magnetic Resonance, 2012

Research paper thumbnail of Combined chelation therapy in thalassemia major for the treatment of severe myocardial siderosis with left ventricular dysfunction

Journal of Cardiovascular Magnetic Resonance, 2008

Research paper thumbnail of A Randomized, Placebo-Controlled, Double-Blind Trial of the Effect of Combined Therapy With Deferoxamine and Deferiprone on Myocardial Iron in Thalassemia Major Using Cardiovascular Magnetic Resonance

Circulation, 2007

Methods and Results— Myocardial iron loading was assessed with the use of myocardial T2* cardiova... more Methods and Results— Myocardial iron loading was assessed with the use of myocardial T2* cardiovascular magnetic resonance in 167 patients with thalassemia major receiving standard maintenance chelation monotherapy with subcutaneous deferoxamine. Of these patients, ...