Positive regularised solutions in electromagnetic inverse scattering

Fredholm integral equations of the first kind are the mathematical model common to several electromagnetic, optical and acoustical inverse scattering problems. In most of these problems the solution must be positive in order to satisfy physical plausibility. We consider ill-posed deconvolution problems and investigate several linear regularization algorithms which provide positive approximate solutions at least in the absence of errors on the data.

Stability Problems in Inverse Diffraction

Inverse diffraction consists in determining the field distribution on a boundary surface from the knowledge of the distribution on a surface situated within the domain where the wave propagates. This problem is a good example for illustrating the use of least-squares methods (also called regularization methods) for solving linear ill-posed inverse problem. We focus on obtaining error bounds For regularized solutions and show that the stability of the restored field far from the boundary surface is quite satisfactory: the error is proportional to ∊(ðŗ‚ ≃ 1) ,ðŗœ being the error in the data (Hölder continuity). However, the error in the restored field on the boundary surface is only proportional to an inverse power of │In∊│ (logarithmic continuity). Such a poor continuity implies some limitations on the resolution which is achievable in practice. In this case, the resolution limit is seen to be about half of the wavelength. Copyright © 1981 by The Institute of Electrical and Electronics Engineers, Inc.

Effect of Bacillus thuringiensis naturally colonising Brassica campestris var. chinensis leaves on neonate larvae of Pieris brassicae

The feeding of neonate larvae of Pieris brassicae (Order Lepidoptera) on leaves of brassica plants that had been colonised by Bacillus thuringiensis resulted in the death of 35% of the population within 72 h. The bacteria Multiplied in the cadavers, resulting in an increase of about 50-fold compared to the living insects. Surviving insects showed no ill effects during the time of the study. There was negligible multiplication of B. thuringiensis in the frass. (C) 2009 Elsevier Inc. All rights reserved.

Understanding changes in cardiovascular pathophysiology

Cardiovascular pathophysiological changes, such as hypertension and enlarged ventricles, reflect the altered functions of the heart and its circulation during ill-health. This article examines the normal and altered anatomy of the cardiac valves, the contractile elements and enzymes of the myocardium, the significance of the different factors associated with cardiac output, and the role of the autonomic nervous system in the heart beat. It also explores how certain diseases alter these functions and result in cardiac symptoms. Nurses can benefit from knowledge of these specific changes, for example, by being able to ask relevant questions in order to ascertain the nature of a patients condition, by being able to take an effective patient history and by being able to read diagnostic results, such as electrocardiograms and cardiac enzyme results. All this will help nurses to promote sound cardiac care based on a physiological rationale.

Foundations for paramedic practice: a theoretical perspective

Written by leading paramedics and academic subject experts, with a foreword by Paul Bates, this is the first foundation level text to introduce the main theoretical subjects studied on the new higher education paramedic science programmes. It underpins practice and links ways of working to the crucial theory base. The numerous examples and case studies focus specifically on pre-hospital and emergency care. Key topics covered include: * NHS and ambulance service history * Ethics and law for the paramedic * Communication and reflective practice * Professional issues, including evidence-based practice, anti-discriminatory practice, clinical governance and clinical audit * Psychological perspectives on health and ill health * Safeguarding children * Sociological perspectives on health and ill health and social policy * Managing change and leadership theory * Continuing professional development The text prompts you to stop and think about what you have just read and relate this to your role. Throughout the book, the author carefully considers how the theory being discussed relates to the role of the ambulance clinician. Foundations for Paramedic Practice: A Theoretical Perspective is a core text for students of paramedic science and will also provide a valuable resource for students of allied health professions. This text provides a stepping stone to further reading and investigation. - Taken from the back cover of: Amanda Blaber - Foundations for paramedic practice: a theoretical perspective

Meeting the emotional needs of parents who have a child with complex needs

The physical and financial demands of caring for a child with complex needs are acknowledged by health professionals. However, the emotional needs of parents are not often recognized by health professionals until parents are at a heightened level of stress. This paper is based on a literature review of current articles, research papers and government documentation. The focus is on the emotional impact to parents who have a child with complex needs, particularly at the point of diagnosis. The paper explores how health professionals, and nurses in particular, should meet the emotional needs of parents in order to support them more effectively. Giving birth to a child with severe health problems impacts upon parents at an emotional time of transition, particularly if there were no concerns identified during pregnancy. For some parents a grief response or state of chronic sorrow may be triggered. The reality of caring for a baby who is critically ill or disabled can be an enormous and unexpected shock for both parents. Parents need emotional support and guidance, as they may have to change their expectations for their child’s development and even life span. It is important for nurses to realise that if parents’ emotional needs are unmet it can lead to clinical depression or mental illness. Primary support often comes from parent support groups rather than health professionals. The review highlights factors affecting parents’ emotions and discusses how early support, home visits and practical help can all help to alleviate parents’ emotional stress.

Critical care in childbearing for midwives

Many women who have higher–risk pregnancies, complications or medical conditions require specialist obstetric or multidisciplinary care. Increasingly women, whose condition deteriorates and becomes critical during childbirth, are being cared for by midwives in obstetric high dependency units within the labour ward, rather than being cared for by nurses in ITU. Critical Care in Childbearing for Midwives explores all aspects of management, support and care of childbearing women who become critically ill due to pre–existing conditions or who develop critical illness as a result of complications of childbearing. It examines predisposing factors which result in the need for critical care, addresses specialist monitoring technology and skills, and explores autonomous practice and team approaches to providing care for critically ill women in childbearing.

Social policy for nurses and the helping professions

The book examines the relationship between welfare and health and includes discussion of key policy issues such as; changes in health care delivery, regulation of professionals, privatisation, welfare pluralism and the tackling of health and social inequalities. The significance of social policy in preventing ill health and disability, as well as supporting the sick and disabled people, is emphasised throughout the book.

Meeting the emotional needs of parents who have a child with complex needs

The physical and financial demands of caring for a child with complex needs are acknowledged by health professionals. However the emotional needs of parents are not often recognised by health professionals until parents are at a heightened level of stress. This paper is based on a literature review of current articles, research papers and government documentation. The focus is on how health professionals, and nurses in particular should meet the emotional needs of parents who have child with complex needs, particularly at the point of diagnosis. Giving birth to a child with severe health problems impacts upon parents at an emotional time of transition, particularly if there were no concerns identified during pregnancy. For some parents a grief response or state of chronic sorrow may be triggered. The reality of caring for a baby who is critically ill or disabled can be an enormous and unexpected shock for both parents. Parents need emotional support and guidance, as they may have to change their expectations for their child’s development and even life span. Primary support often comes from parent support groups rather than health professionals. The review discusses how home visits, practical help and early support can all help to alleviate stress. It is important for nurses to realise that if parents’ emotional needs are unmet they can lead to clinical depression or mental illness. This literature review looks at the emotional impact on parents and explores how nurses can address this issue in order to support parents more effectively. It identifies key areas that nurses could address that would help alleviate parents’ emotional stress.

Application of regularization methods to damage detection in large scale plane frame structures using incomplete noisy modal data

This paper presents an approach for detecting local damage in large scale frame structures by utilizing regularization methods for ill-posed problems. A direct relationship between the change in stiffness caused by local damage and the measured modal data for the damaged structure is developed, based on the perturbation method for structural dynamic systems. Thus, the measured incomplete modal data can be directly adopted in damage identification without requiring model reduction techniques, and common regularization methods could be effectively employed to solve the developed equations. Damage indicators are appropriately chosen to reflect both the location and severity of local damage in individual components of frame structures such as in brace members and at beam-column joints. The Truncated Singular Value Decomposition solution incorporating the Generalized Cross Validation method is introduced to evaluate the damage indicators for the cases when realistic errors exist in modal data measurements. Results for a 16-story building model structure show that structural damage can be correctly identified at detailed level using only limited information on the measured noisy modal data for the damaged structure.

The Olympic Games and urban displacement: the case of Beijing

Urban spectacles such as the Olympic Games have been long perceived as being able to impose desired effects in the city that act as host. This kind of urban boost may include the creation of new jobs and revenue for local community, growth in tourism and convention business, improvements to city infrastructure and environment, and the stimulation of broad reform in the social, political and institutional realm. Nevertheless at the other end of the debate, the potentially detrimental impacts of Olympic urban development, particularly on disadvantaged and vulnerable groups, have also been increasingly noticed in recent years and subsequently cited by a number of high profile anti-Olympic groups to campaign against Olympic bids and awards. The common areas of concern over Olympic-related projects include the cost and debts risk, environmental threat, the occurrence of social imbalance, and disruption and disturbance of existing community life. Among these issues, displacement of low income households and squatter communities resulting from Olympic-inspired urban renewal are comparatively under-explored and have emerged as an imperative area for research inquiry. This is particularly the case where many other problems have become less prominent. Changing a city’s demographic landscape, particularly displacing lower income people from the area proposed for a profitable development is a highly contentious matter in its own right. Some see it as a natural and inevitable outgrowth of the process of urban evolution, without which cities cannot move towards a more attractive location for consumption-based business. Others believe it reflects urban crises and conflicts, highlighting the market failures, polarization and injustice. Regardless of perception,these phenomena are visible everywhere in post-industrial cities and particularly cannot be ignored when planning for the Olympic Games and other mega-events. The aim of this paper is to start the process of placing the displacement issue in the context of Olympic preparation and to seek a better understanding of their interrelations. In order to develop a better understanding of this issue in terms of cause, process, influential factors and its implication on planning policy, this paper studies the topic from both theoretic and empirical angles. It portrays various situations where the Olympics may trigger or facilitate displacement in host cities during the preparation of the Games, identifies several major variables that may affect the process and the overall outcome, and explores what could be learnt in generic terms for planning Olympic oriented infrastructure so that ill-effects to the local community can be effectively controlled. The paper concludes that the selection of development sites, the integration of Olympic facilities with the city’s fabric, the diversity of housing type produced for local residents and the dynamics of the new socioeconomic structure.

MENTAL HEALTH AND CRIMINALITY AMONG PSYCHIATRIC OFFENDERS IN SOUTHEASTERN ONTARIO

OBJECTIVES: (1) Describe the population of mentally ill offenders over whom Ontario Review Board (ORB) held jurisdiction. (2) Assess the influences of psychopathology and criminal factors on criminal career. METHOD: This study was a retrospective case series design that reviewed all offenders who were court ordered for psychiatric evaluation at Mental Health Services Site of Providence Care in Kingston, Ontario from 1993 to 2007 (N=347). Eighty five subjects were found not criminally responsible on the account of mental disorder and were included in statistical analysis (n=85). Bivariate associations between five key variables and two outcome variables, seriousness of crime and recidivism, were examined. Logistic regressions were conducted to test the role of the predictor variables on the outcome variables. RESULTS: Age and change in principal psychiatric diagnosis over time were shown to be associated with seriousness of crime. Timing of psychiatric onset, early signs of deviance and change in diagnosis were shown to be associated with recidivism. On the whole, study population did not markedly vary in their distribution of variables by the outcome variables. Regression model included timing of psychiatric onset; psychiatric history; existence of criminal associate; child abuse history; and early signs of deviance. Recidivism was shown to be predicted by early signs of deviance (OR=8.154, p<0.05). Existence of criminal associates was shown to have substantial values of odds ratio at marginal significance (OR=7.577, p=0.13). CONCLUSION: Seriousness of crime is a complex factor that could not be sufficiently predicted by any one or combinations of study variables. Recidivism is better predicted by criminality factors than psychopathology. In the future, an exploratory analysis that more broadly examines the psychopathology and criminal factors in Canadian forensic population is needed. Findings from this study have important clinical and legal implications.

Selective migration from deprived areas in Northern Ireland and the spatial distribution of inequalities: implications for monitoring health and inequalities in health

Much of the evidence suggesting that inequalities in health have been increasing over the last two decades has come from studies that compared the changes in relative health status of areas over time. Such studies ignore the movement of people between areas. This paper examines the population movement between small areas in Northern Ireland in the year prior to the 1991 census as well as the geographical distribution of migrants to Northern Ireland over the same period. It shows that deprived areas tended to become depopulated and that those who left these areas were the more affluent residents. While immigrants differed a little from the indigenous population, the overall effect of their distribution would be to maintain the geographical socio-economic status quo. The selective movement of people between areas would result in the distribution of health and ill-health becoming more polarized, i.e. produce a picture of widening inequalities between areas even though the distribution between individuals is unchanged. These processes suggest potential significant problems with the area-based approaches to monitoring health and inequalities in health.

La incidencia de los valores culturales en el voluntariado: el caso de Europa

La realidad del voluntariado es sumamente compleja hasta el punto de que resulta complicado definir y caracterizar el trabajo voluntario, dada la gran variedad de interpretaciones, motivaciones, variables sociodemográficas y aspectos culturales que configuran el perfil de los voluntarios. El objetivo de este trabajo es analizar la influencia conjunta de algunas variables sociodemográficas, así como de los valores culturales de índole secular o tradicional, sobre el perfil de los voluntarios en Europa. Además, se investiga qué variables orientan a los voluntarios hacia un determinado tipo de voluntariado u otro. Para ello se ha aplicado principalmente una metodología de regresión logística a partir de la información disponible en la European Value Study. Los resultados obtenidos ayudan a establecer una caracterización del voluntariado en Europa, y confirman la influencia de los valores culturales, en primer lugar, en la realización o no de trabajos de voluntariado, y en segundo lugar, en la elección que hacen estas personas del tipo de actividad con la que están comprometidos. Al analizar dos tipos de voluntariado de motivación supuestamente muy diferente, se concluye que existe un grupo de valores que influyen en ambos, aunque el sentido y la intensidad en la que lo hacen sea diferente; por otra parte, algunos valores tienen influencia o no en la realización de trabajos de voluntariado, dependiendo del tipo específico al que nos refiramos.

Distribution-based adaptive bounding genetic algorithm for continuous optimisation problems

A new search-space-updating technique for genetic algorithms is proposed for continuous optimisation problems. Other than gradually reducing the search space during the evolution process with a fixed reduction rate set ‘a priori’, the upper and the lower boundaries for each variable in the objective function are dynamically adjusted based on its distribution statistics. To test the effectiveness, the technique is applied to a number of benchmark optimisation problems in comparison with three other techniques, namely the genetic algorithms with parameter space size adjustment (GAPSSA) technique [A.B. Djurišic, Elite genetic algorithms with adaptive mutations for solving continuous optimization problems – application to modeling of the optical constants of solids, Optics Communications 151 (1998) 147–159], successive zooming genetic algorithm (SZGA) [Y. Kwon, S. Kwon, S. Jin, J. Kim, Convergence enhanced genetic algorithm with successive zooming method for solving continuous optimization problems, Computers and Structures 81 (2003) 1715–1725] and a simple GA. The tests show that for well-posed problems, existing search space updating techniques perform well in terms of convergence speed and solution precision however, for some ill-posed problems these techniques are statistically inferior to a simple GA. All the tests show that the proposed new search space update technique is statistically superior to its counterparts.