Direct and pulsed current annealing of p-MOSFET based dosimeter: the “MOSkin”

Contemporary radiation therapy (RT) is complicated and requires sophisticated real-time quality assurance (QA). While 3D real-time dosimetry is most preferable in RT, it is currently not fully realised. A small, easy to use and inexpensive point dosimeter with real-time and in vivo capabilities is an option for routine QA. Such a dosimeter is essential for skin, in vivo or interface dosimetry in phantoms for treatment plan verification. The metal-oxide-semiconductor-field-effect-transistor (MOSFET) detector is one of the best choices for these purposes, however, the MOSFETs sensitivity and its signal stability degrade after essential irradiation which limits its lifespan. The accumulation of positive charge on the gate oxide and the creation of interface traps near the silicon–silicon dioxide layer is the primary physical phenomena responsible for this degradation. The aim of this study is to investigate MOSFET dosimeter recovery using two proposed annealing techniques: direct current (DC) and pulsed current (PC), both based on hot charged carrier injection into the gate oxide of the p-MOSFET dosimeter. The investigated MOSFETs were reused multiple times using an irradiation-annealing cycle. The effect of the current-annealing parameters was investigated for the dosimetric characteristics of the recovered MOSFET dosimeters such as linearity, sensitivity and initial threshold voltage. Both annealing techniques demonstrated excellent results in terms of maintaining a stable response, linearity and sensitivity of the MOSFET dosimeter. However, PC annealing is more preferable than DC annealing as it offers better dose response linearity of the reused MOSFET and has a very short annealing time.     

The Origin of the Term “Pneumonokoniosis”

Throughout the literature on the dust diseases of the lungs, reference is frequently made to the fact that Professor F. A. Zenker of Erlangen introduced the term “pneumonokoniosis”. As few authors have been able to study the original German article, this opportunity has been taken to present a translation in English prefaced by a short biographical note.     

The king’s foot of patient-reported outcomes: current practices and new developments for the measurement of change

Purpose  

Assessing change remains a challenge in patient-reported outcomes. In June 2009, a group of psychometricians, biostatisticians, and behavioral researchers from other disciplines convened as a Longitudinal Analysis of Patient-Reported Outcomes Working group as part of the Statistical and Applied Mathematical Sciences Institute Summer Psychometric program to discuss the complex issues that arise when conceptualizing and operationalizing “change” in patient-reported outcome (PRO) measures and related constructs. This white paper summarizes these issues and provides recommendations and possible paths for dealing with the complexities of measuring change.     

The end of the line: has rapid transit contributed to the spatial diffusion of HIV in one of Canada's largest metropolitan areas?

The objective of this study is to describe the relationship between socio-demographic characteristics and the geographic distribution of persons with HIV in the metropolitan area surrounding Vancouver, British Columbia. Specifically, we sought to determine the location of persons with HIV and the population based characteristics related to the rate of anti-HIV medication use. In addition, we investigated the relationship between the distribution of persons on anti-HIV medications and the city's monorail "SkyTrain" route. The residences of persons on anti-HIV therapy were linked to Census Tracts. Data from the most recent census were used to create a socio-demographic profile of each geographic area. The spatial relationship between the distribution of persons on anti-HIV therapy and the path of the monorail was assessed by digitizing the SkyTrain route over a digital Census Tract map. Statistical analyses were used to determine the characteristics of Census Tracts associated with the rate of anti-HIV medication use. The overall rate of anti-HIV medication use in the Census Tracts that are within 1 km of SkyTrain was 66 per 100,000 population, whereas the rate was only 22 in the non-proximal Census Tracts. Multivariate analyses indicated that persons on anti-HIV therapy were significantly less likely to reside where there is a higher proportion of the population female, and were more likely to reside in areas with a higher proportion of the population of First Nations or Aboriginal descent, a higher population density, and in areas within 1 km of the SkyTrain route. Our analyses suggest that neither migration, nor a heightened access to therapy explain these findings. The environment surrounding the SkyTrain may have been conducive to the spatial diffusion of HIV, and could be the focus of targeted public health interventions. The mechanisms responsible for the clustering of persons on anti-HIV medications around the SkyTrain require further investigation.     

To the class of 2005: Will you be ready for the quality revolution?

BACKGROUND: Graduates are becoming aware of the vast changes occurring in the health care and scientific environments, which will place unprecedented demands on them. A SECOND REVOLUTION: It has been suggested that the Institute of Medicine reports To Err Is Human and Crossing the Quality Chasm have alerted healthcare professionals and managers to system defects, enlisted a broad array of stakeholders in the agenda, and accelerated changes in practice needed to eliminate errors and unnecessary deaths. It is now commonplace for comparative data on the effectiveness of hospitals and medical groups to be published in this new age of transparency. Coalitions of employers are now urging the adoption of safer practices in hospitals. In addition, the science of quality improvement has flourished and become robust. COMING CHANGES AND POSSIBILITIES: The changes over the next five years will be breathtaking. Those doctors and hospitals with the best clinical outcomes will benefit from seeing more patients and may even be paid more by Medicare, Medicaid, and insurance companies. Patients will access, via the Web, the latest quality information and make more informed choices about where to seek their care. The environment in which care is provided is also undergoing a major transformation. Hospital buildings themselves are becoming more healing, safer places. Graduates may ask themselves, "Will my residency adequately prepare me to understand and apply the science of quality improvement and evidence-based practice?"     

The incomparability of cause of death statistics under “one country,two systems”: Shanghai versus Hong Kong

Background

Valid and comparable cause of death (COD) statistics are crucial for health policy analyses. Variations in COD assignment across geographical areas are well-documented while socio-institutional factors may affect the process of COD and underlying cause of death (UCD) determination. This study examines the comparability of UCD statistics in Hong Kong and Shanghai, having two political systems within one country, and assesses how socio-institutional factors influence UCD comparability.

Methods

A mixed method was used. Quantitative analyses involved anonymized official mortality records. Mortality rates were analyzed by location of death. To analyze the odds ratio of being assigned to a particular UCD, logistic regressions were performed. Qualitative analyses involved literature reviews and semi-structural interviews with key stakeholders in death registration practices. Thematic analysis was used.

Results

Age-standardized death rates from certain immediate conditions (e.g., septicemia, pneumonia, and renal failure) were higher in Hong Kong. Variations in UCD determination may be attributed to preference of location of death, procedures of registering deaths outside hospital, perceptions on the causal chain of COD, implications of the selected UCD for doctors’ professional performance, and governance and processes of data quality review.

Conclusions

Variations in socio-institutional factors were related to the process of certifying and registering COD in Hong Kong and Shanghai. To improve regional data comparability, health authorities should develop standard procedures for registering deaths outside hospital, provide guidelines and regular training for doctors, develop a unified automated coding system, consolidate a standard procedure for data review and validity checks, and disseminate information concerning both UCD and multiple causes of death.

     

The “Sandwich Mom”: In the Throes of a Medication Safety “Perfect Storm”

America is entering into a proverbial “perfect storm” of medication errors. Medications are more complex and their use is increasing, consumers are more involved in their healthcare decisions, and the population is aging and with it comes diminished cognitive skills. “Sandwich moms” are likely to bear the brunt of the ravages of this storm. These are the women who serve multiple roles as caregivers for their children, spouses, and, increasingly, their parents. This study explores how concerned these caregivers are about potential harm from medication use and how likely they would be to become more involved in medication management activities.     

The genomic revolution: is the real risk under-investment rather than bankrupt health care systems?

There is an element of 'scientific determinism' in much of the discussion of the genomic revolution. Recognition of the potential for improving health is more than matched by worries about both the ability of health care systems to cope and the potential for genetic testing to lead to discrimination. There are five main uses for genomics in the development of human diagnostics and therapeutics: pharmacogenomics, gene therapy, pharmacogenetics, genetic testing of symptomatic or at risk people, and population genotyping. Although there are potential health gains, several concerns exist: health gain may increase funding pressures on health care systems; providing cost-effectiveness thresholds may mean drugs for some patient groups may not be developed; random population genetic testing will meet economic and ethical obstacles; and private sector patenting risks a loss of data and access to data, which will inhibit the development of potentially cost-effective tests and therapies.     

The “Father of Stress” Meets “Big Tobacco”: Hans Selye and the Tobacco Industry

The concept of stress remains prominent in public health and owes much to the work of Hans Selye (1907–1982), the “father of stress.” One of his main allies in this work has never been discussed as such: the tobacco industry.After an analysis of tobacco industry documents, we found that Selye received extensive tobacco industry funding and that his research on stress and health was used in litigation to defend the industry''s interests and argue against a causal role for smoking in coronary heart disease and cancer.These findings have implications for assessing the scientific integrity of certain areas of stress research and for understanding corporate influences on public health research, including research on the social determinants of health.An analysis of internal tobacco industry documents since the 1990s has revealed extensive efforts by the industry over decades to undermine the scientific evidence on smoking and health. These efforts include commissioning research from pro-industry scientists to challenge scientific findings and offer alternative explanations. To this end, the industry created the Council for Tobacco Research (CTR) in 1953, initially known as the Tobacco Industry Research Council, to fund research with significant “adversary value.”¹ Award letters for CTR “special projects” instructed recipients not to disclose that such research was undertaken predominantly for litigation purposes¹ or that industry legal reviews, rather than the normal scientific peer review process, served as the basis for publication.^2–4Previous analyses have shown how scientists were used to defend and promote smoking, thus giving the impression of “a chorus of seemingly authoritative voices from respected institutions around the world spreading damaging arguments designed to benefit the tobacco companies and damage health.”⁵ Smoking bans to protect against secondhand smoke (SHS) were undermined by paying scientists to disseminate industry messages in the United States.⁶ In Europe, the industry attempted to infiltrate the World Health Organization''s cancer research arm and the International Agency for Research on Cancer; under what was known as “Project Whitecoat,” it aimed to recruit “groups of scientists [that] should be able to produce research or stimulate controversy in such a way that public affairs people in the relevant countries would be able to make use of or market the information.”^7,8 In China, British American Tobacco funded liver disease research to divert attention from SHS.² It has also been shown that social scientists were used to promote smoking in many countries, including the United Kingdom, the United States, Australia, New Zealand, South Africa, and Germany.⁵We analyzed another important strand of tobacco industry–funded research not hitherto described: the relationship between stress and illness. Stress is regularly cited as an important social determinant of health.^9–15 Contemporary research on stress, however, must take into account the decades-long support by the tobacco industry for stress-related research beginning with the role of physiologist Hans Selye (1907–1982). Selye developed the concept through animal studies from 1933 to 1945^16,17 and popularized it in many best-selling books.¹⁸ In 1977 he retired and set up the International Institute of Stress in Montreal and the Hans Selye Foundation to fund stress research.¹⁹ Selye drew parallels between his own career and that of the chemist and microbiologist Louis Pasteur.¹⁷ He died in 1982, having been hailed the “father of stress.” During his career, he wrote 1700 articles and 39 books, was nominated for the Nobel Prize 10 times, and received the Order of Canada, one of the country''s highest honors.^20–22Selye''s links to the tobacco industry have not been hitherto examined, to our knowledge. We analyzed internal industry documents and describe how the industry funded his work, used him as an expert witness in legal proceedings, and made extensive use of his research for litigation and public relations. Our findings raise important questions about assessing the scientific integrity of stress research and about the scope of the industry''s influence on public health research and policy.     

The Rationalization of Unethical Research: Revisionist Accounts of the Tuskegee Syphilis Study and the New Zealand “Unfortunate Experiment”

Two studies, widely condemned in the 1970s and 1980s—the Tuskegee study of men with untreated syphilis and the New Zealand study of women with untreated carcinoma in situ of the cervix—received new defenses in the 21st century.We noted remarkable similarities in both the studies and their defenses. Here we evaluate the scientific, political, and moral claims of the defenders.The scientific claims are largely based on incomplete or misinterpreted evidence and exaggeration of the uncertainties of science. The defenders’ political arguments mistakenly claim that identity politics clouded the original critiques; in fact such politics opened the eyes of the public to exploitation. The moral defenses demonstrate an overreliance on codes of conduct and have implications for research ethics today.In Dark Medicine: Rationalizing Unethical Medical Research, William LaFleur describes how rationalizations initially masquerade as reasons—but they are insufficient or invalid.1 Even Nazi physicians experimenting in the concentration camps rationalized their actions. These acts were grossly immoral, yet behind them were moral justifications. Those involved used these justifications to suppress and subdue their moral intuitions.2 These were rationalizations offered at the time, but such justifications can also be made in the present for the past actions of others, though the motives for doing so are different. We use the idea of rationalization to explore recent revisionist accounts of what have been widely regarded as unethical medical studies.The Tuskegee syphilis study in Macon Country, Alabama, has been described as an egregious case of blatant racism.3 Nevertheless, it has always had its defenders, such as those who rushed to justify it when the study first came to public attention in the 1970s.4 In the 21st century, physician Robert White and cultural anthropologist Richard Shweder have proffered a fresh defense, suggesting that the study was neither unethical nor racist.5 Similarly, by the late 1980s a cervical precancer study in Auckland, New Zealand, was widely considered to be emblematic of unethical research and of the failures of professional self-regulation.6 This “unfortunate experiment”7 at the National Women’s Hospital had many similarities to the Tuskegee study. Defense of the unfortunate experiment is not new,8 but the established accounts of the study, that women with carcinoma in situ (CIS) of the cervix9 were followed but not treated, have recently been described as misjudged, both factually and ethically.10The status afforded these new accounts is important. The Tuskegee and New Zealand studies have provided models of unethical practice for a generation of physicians and researchers. The US Belmont Report was prompted by the Tuskegee study revelations.11 The New Zealand cervical cancer study was subject to a judicial inquiry and report (the Cartwright Inquiry),12 and the subsequent recommendations led to wide-ranging changes in that country, including a legally enforceable code of patients’ rights and the appointment of a health and disability commissioner with powers to investigate complaints of breaches of the code.13It would be wrong to exaggerate the importance of the new defenses. Though a Lancet Infectious Diseases editorial in 2005 used White’s and Shweder’s revisionist accounts to question whether the Tuskegee study was unethical or racist,14 these interpretations have not been widely cited. Similarly, though the New Zealand Medical Journal carried an invited editorial by the defender of the cervical cancer study, historian Linda Bryder,15 and the Royal Society of London published an admiring review of Bryder’s book,16 elsewhere her work has been strongly criticized.17 The latest revelation about the involvement of Tuskegee investigator John Cutler in deliberately infecting people with gonorrhea and syphilis in Guatemala in the 1940s should have put an end to defenses of the ethics of those investigators.18 Nevertheless, as historian Susan Reverby points out about the Tuskegee study, “There is a truth to what actually happened, and trying to understand it does matter.” She says that the revisionists’ arguments should be considered, “if for no other reason than to understand why they are being made.”19Here we provide an overview, informed by the reports of the official inquiries, of the 2 studies’ similarities and differences.20 We draw on evidence from the original inquiries, historical accounts, and reports by the study investigators themselves to evaluate the scientific claims made by the defenders and explain their errors in reasoning. We also explore the political context in which the studies came to attention and the defenders’ moral claims.Although the studies began in different historical periods (1932 in Alabama, 1966 in New Zealand), they came to light at a similar time (1970s and 1980s), and the revisionist accounts were written at a similar period (the first decade of the 21st century). Examining the accounts together casts a light on the way rationalization of unethical practices in the past takes a particular form in our own day.