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Magnetic resonance imaging (MRI) is one of the most important diagnostic tools in modern medicine. Since it is a high-cost and highly-complex imaging modality, computational models are frequently built to enhance its understanding as well as to support further development. However, such models often have to be simplified to complete simulations in a reasonable time. Thus, the simulations with high spatial/temporal resolutions, with any motion consideration (like blood flow) and/or with 3D objects usually call for using parallel computing environments.In this paper, we propose to use graphics processing units (GPUs) for fast simulations of MRI of vascular structures. We apply a CUDA environment which supports general purpose computation on GPU (GPGPU). The data decomposition strategy is applied and thus the parts of each virtual object are spread over the GPU cores. The GPU cores are responsible for calculating the influence of blood flow behavior and MRI events after successive time steps. In the proposed approach, different data layouts, memory access patterns, and other memory improvements are applied to efficiently exploit GPU resources. Computational performance is thoroughly validated for various vascular structures and different NVIDIA GPUs. Results show that MRI simulations can be accelerated significantly thanks to GPGPU. The proposed GPU-based approach may be easily adopted in the modeling of other flow related phenomena like perfusion, diffusion or transport of contrast agents. [ABSTRACT FROM AUTHOR]

Background: Hospital governance is broadening its orientation from cost and production controls towards 'improving performance on clinical outcomes'. Given this new focus one might assume that doctors are drawn into hospital management across OECD countries. Hospital performance in terms of patient health, quality of care and efficiency outcomes is supposed to benefit from their involvement. However, international comparative evidence supporting this idea is limited. Just a few studies indicate that there may be a positive relationship between medical doctors being part of hospital boards, and overall hospital performance. More importantly, the assumed relationship between these so-called doctor managers and hospital performance has remained a 'black-box' thus far. However, there is an increasing literature on the implementation of quality management systems in hospitals and their relation with improved performance. It seems therefore fair to assume that the relation between the involvement of doctors in hospital management and improved hospital performance is partly mediated via quality management systems. The threefold aim of this paper is to 1) perform a quick scan of the current situation with regard to doctor managers in hospital management in 19 OECD countries, 2) explore the phenomenon of doctor managers in depth in 7 OECD countries, and 3) investigate whether doctor involvement in hospital management is associated with more advanced implementation of quality management systems.Methods: This study draws both on a quick scan amongst country coordinators in OECD's Health Care Quality Indicator program, and on the DUQuE project which focused on the implementation of quality management systems in European hospitals.Results: This paper reports two main findings. First, medical doctors fulfil a broad scope of managerial roles at departmental and hospital level but only partly accompanied by formal decision making responsibilities. Second, doctor managers having more formal decision making responsibilities in strategic hospital management areas is positively associated with the level of implementation of quality management systems.Conclusions: Our findings suggest that doctors are increasingly involved in hospital management in OECD countries, and that this may lead to better implemented quality management systems, when doctors take up managerial roles and are involved in strategic management decision making. [ABSTRACT FROM AUTHOR]

The article asks about the function of clinical ethics. It does so by confronting the assumption that ethics is supposed to help in the solution of concrete problems, relying upon a defined set of principles and rules. The scientific character of such an approach to clinical ethics complements the very understanding of modern medicine as being increasingly scientific and technical; that is, as oriented toward the production of effects. The paper claims that, rather than sharing in the "suspension of meaning" pursued by medicine for the sake of scientific objectivity, the main task of clinical ethics consists of a retrieval, or "anamnesis," of the very questions medicine seems to suspend: the significance of illness and disease, of birth, suffering and death, and of the service to the ethos of generosity that sustains the healing professions. Also, the paper offers a cultural "etiology" of "the suspension of meaning" in ethics, and pleads for a moral reflection that begins with a free and open confrontation with clinical experience. Attending to the moral meaning of concrete situations, the paper argues that formal modes of logical argumentation are only derivative functions of the moral language and, thus, cannot exhaust the broad spectrum of ethical discourse in medicine. [ABSTRACT FROM AUTHOR]

A scientist's choice of research problem affects his or her personal career trajectory. Scientists' combined choices affect the direction and efficiency of scientific discovery as a whole. In this paper, we infer preferences that shape problem selection from patterns of published findings and then quantify their efficiency. We represent research problems as links between scientific entities in a knowledge network. We then build a generative model of discovery informed by qualitative research on scientific problem selection. We map salient features from this literature to key network properties: an entity's importance corresponds to its degree centrality, and a problem's difficulty corresponds to the network distance it spans. Drawing on millions of papers and patents published over 30 years, we use this model to infer the typical research strategy used to explore chemical relationships in biomedicine. This strategy generates conservative research choices focused on building up knowledge around important molecules. These choices become more conservative over time. The observed strategy is efficient for initial exploration of the network and supports scientific careers that require steady output, but is inefficient for science as a whole. Through supercomputer experiments on a sample of the network, we study thousands of alternatives and identify strategies much more efficient at exploring mature knowledge networks. We find that increased risk-taking and the publication of experimental failures would substantially improve the speed of discovery. We consider institutional shifts in grant making, evaluation, and publication that would help realize these efficiencies. [ABSTRACT FROM AUTHOR]

Background: Over the past 30 years, the international conference on Artificial Intelligence in MEdicine (AIME) has been organized at different venues across Europe every 2 years, establishing a forum for scientific exchange and creating an active research community. The Artificial Intelligence in Medicine journal has published theme issues with extended versions of selected AIME papers since 1998.Objectives: To review the history of AIME conferences, investigate its impact on the wider research field, and identify challenges for its future.Methods: We analyzed a total of 122 session titles to create a taxonomy of research themes and topics. We classified all 734 AIME conference papers published between 1985 and 2013 with this taxonomy. We also analyzed the citations to these conference papers and to 55 special issue papers.Results: We identified 30 research topics across 12 themes. AIME was dominated by knowledge engineering research in its first decade, while machine learning and data mining prevailed thereafter. Together these two themes have contributed about 51% of all papers. There have been eight AIME papers that were cited at least 10 times per year since their publication.Conclusions: There has been a major shift from knowledge-based to data-driven methods while the interest for other research themes such as uncertainty management, image and signal processing, and natural language processing has been stable since the early 1990s. AIME papers relating to guidelines and protocols are among the most highly cited. [ABSTRACT FROM AUTHOR]

The article presents abstracts of medical studies whose full versions can be found at www.blackwellpublishing.com/dmcn including one regarding the relationship between gross motor capacity and daily-life mobility in children with cerebral palsy (CP), a longitudinal study of participation trajectories in children with and without developmental coordination disorders (DCD), and the impact of early-life androgens on infant brain development.

Aim: To determine adherence to clinical practice guidelines in the medical, physiotherapy and chiropractic professions for acute and subacute mechanical low back pain through best-evidence synthesis of the healthcare literature. Methods: A structured best-evidence synthesis of the relevant literature through a literature search of relevant databases for peer-reviewed papers on adherence to clinical practice guidelines from 1995 to 2013. Inclusion of papers was based on selection criteria and appraisal by two reviewers who independently applied a modified Downs & Black appraisal tool. The appraised papers were summarized in tabular form and analysed by the authors. Results: The literature search retrieved 23 potentially relevant papers that were evaluated for methodological quality, of which 11 studies met the inclusion criteria. The main finding was that no profession in the study consistently attained an overall high concordance rating. Of the three professions examined, 73% of chiropractors adhered to current clinical practice guidelines, followed by physiotherapists (62%) and then medical practitioners (52%). Conclusions: This review showed that quality papers in this area of research are very limited. Notwithstanding, chiropractors appear to adhere to clinical practice guidelines more so than physiotherapists and medical practitioners, although there is scope for improvement across all three professions. [ABSTRACT FROM AUTHOR]

Highlights: [•] This paper reviews data mining application in medicine from 1999 to 2013. [•] Medical data mining definition and its main goals and challenges are clarified. [•] Comprehensive categorization is presented to complete previous works and integrate medical and data mining issues. [•] Each paper is studied from six medical tasks and in each tasks, five data mining approaches are considered. [•] A discussion deals with previous research outline and future trend. [Copyright &y& Elsevier]

An abstract of a paper on nucleoside diphosphate kinase is presented.

In Longoni et al. (2019), we examine how algorithm aversion influences utilization of healthcare delivered by human and artificial intelligence providers. Pezzo and Beckstead's (2020) commentary asks whether resistance to medical AI takes the form of a noncompensatory decision strategy, in which a single attribute determines provider choice, or whether resistance to medical AI is one of several attributes considered in a compensatory decision strategy. We clarify that our paper both claims and finds that, all else equal, resistance to medical AI is one of several attributes (e.g., cost and performance) influencing healthcare utilization decisions. In other words, resistance to medical AI is a consequential input to compensatory decisions regarding healthcare utilization and provider choice decisions, not a noncompensatory decision strategy. People do not always reject healthcare provided by AI, and our article makes no claim that they do. [ABSTRACT FROM AUTHOR]

Positive long-term treatment outcome in cancer patients depends mainly on the disease stage. It also depends on selection of an optimum therapeutic management. In breast cancer patients, the final treatment arrangements result, to a large extent, from a quality of cooperation of medical personnel providing cancer diagnostics and therapy. This requires knowledge of mutual expectations of doctors of different specialisations. The most common problems in interdisciplinary communication are relatively easy to notice in relations between a clinician (surgeon) and a pathologist. This paper discusses the most important aspects of that relationship. [ABSTRACT FROM AUTHOR]

In this paper, we derive mathematical models for the dynamics of superparamagnetic nanoparticles under the influence of applied magnetic fields. Such models are needed in many applications, e.g. magnetic drug targeting in cancer therapy. They are the starting point for the development of stable numerical approaches and for the formulation of optimization problems, which are needed for the optimal design of magnetic field configurations. Furthermore, we show the existence and uniqueness of classical radially symmetrical solutions and illustrate their qualitative behaviour by numerical simulations using Matlab. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of shiphandling manoeuvres on mental workload and physiological reactions in ten marine pilots. Each pilot performed four berthings in a ship simulator. Those berthings were differentiated by two factors, level of difficulty and familiarity with the port. Each berthing could also be divided into five phases, three during the execution and two resting periods, one before and one after the execution (dedicated to baseline physiological data collection). Mental workload was measured through two self assessment scales: the NASA TLX and a Likert scale. Power spectral densities on Beta bands 1 and 2 were obtained from EEG. Heart rate and heart rate variability were obtained from ECG. Pupil dilation was obtained from eye tracking. Workload levels were higher as berthings increased in difficulty level and/or the pilots completed the berthings in unfamiliar ports. Responses differed across specific phases of the berthings. Physiological responses could indirectly monitor levels of mental workload, and could be adopted in future applications to evaluate training improvements and performance. This study provides an example of an applied methodology aiming to define an upper redline of task demands in the context of marine pilotage. [ABSTRACT FROM AUTHOR]

Although there are only three professions in the world: medicine, law and priesthood (the others are skills, crafts, occupations, etc.), the paper deals with only two of them, human medicine and medical law, regarding their joint actions and benefits that people can expect. In addition to perceiving of synergistic activities, the authors explore whether each state designs a correct national strategy in its health policy, whether it is aimed at developing a modern and contented health system, the improvement of the health quality of the population, extension of human life, application of modern medical knowledge and does it predict the up-to-date control of the use of available resources? While human medicine is being glorified because of the high quality of human health, medical law provokes contradictory opinions of general and professional public, since the laws, measures, regulations and other legal instruments are used in order to regulate the health system and to control its business processes. Many argue that this is an unnecessary, unprincipled, superfluous and irritating interference in the domain of medicine, which brings more damage than benefits. For them, the mentioned processes have purely medical character and therefore consider that their control (when necessary) can be performed exclusively by healthcare professionals, individually or through professional associations and / or chambers. Other authors deny the aforementioned opinions using arguments as: the rapid development of medical science, a large number of health institutions, sectors and services, and its strong dependence on economic, technical and legal logistics. The conflict of opinions is best negated by the practice, because medical law represents a very important compounder of the health system, since it protects the rights of insured and health workers and fosters the trust of citizens in human medicine. [ABSTRACT FROM AUTHOR]

Students tend to be very interested in medical issues that affect them and their friends and family. Using cancer as a hook, the ART of Reproductive Medicine: Oncofertility curriculum (free, online, and NIH sponsored) has been developed to supplement the teaching of basic biological concepts and to connect biology and biomedical research. This approach allows integration of up-to-date information on cancer and cancer treatment, cell division, male and female reproductive anatomy and physiology, cryopreservation, fertility preservation, stem cells, ethics, and epigenetics into an existing biology curriculum. Many of the topics covered in the curriculum relate to other scientific disciplines, such as the latest developments in stem cell research including tissue bioengineering and gene therapy for inherited mitochondrial disease, how epigenetics occurs chemically to affect gene expression or suppression and how it can be passed down through the generations, and the variety of biomedical careers students could pursue. The labs are designed to be open-ended and inquiry-based, and extensions to the experiments are provided so that students can explore questions further. Case studies and ethical dilemmas are provided to encourage thoughtful discussion. In addition, each chapter of the curriculum includes links to scientific papers, additional resources on each topic, and NGSS alignment. [ABSTRACT FROM AUTHOR]

Indigenous knowledge points to the fact that Africa has been able to generate, test and apply knowledge through its own methodologies and approaches. This knowledge sustained communities for years prior to colonialism which somehow downplayed the value of indigenous knowledge and promoted western knowledge systems. Colonialism created dependence on western knowledge systems and Africa has over the years neglected its own rich indigenous knowledge. This paper sought to highlight challenges faced in the quest to incorporate IK into developmental goals and projects. Furthermore, the study also sought to recommend ways through which Africans can promote IK in its developmental projects. A desk research was carried out to show the challenges faced in African indigenous knowledge. The results of the study showed that there was a need for policies, legislation, standards, research capacitation, investment and local inclusion in indigenous knowledge research, documentation and use. The study also pointed to the fact that indigenous knowledge could be tapped into for developmental goals and projects. [ABSTRACT FROM AUTHOR]

Research in the field of health with the participation of social anthropology in Chile is scarce. On the other hand, studies in social sciences, whether funded by the state and / or universities, are usually not linked to concrete problems. In this context, this paper presents an experience of forming an interdisciplinary team that has tried to know the medical models of indigenous origin in the Chilean north and the strategies of attention to the diseases deployed by Aymara families. Its purpose is to address the problems faced by health and social sciences professionals, the constraints generated by specialized training to find solutions in specific situations, and the difficulties that arise for transdisciplinary research. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to introduce a new condition ( C ) α ∫ 0 u f ( s ) d s ≤ u f ( u ) + β u 2 + γ , u > 0 for some α , β , γ > 0 with 0 < β ≤ α − 2 λ 0 2 , where λ 0 is the first eigenvalue of discrete Laplacian Δ ω , with which we obtain blow-up solutions to discrete semilinear heat equations u t x , t = Δ ω u x , t + f ( u ( x , t ) ) , x , t ∈ S × 0 , + ∞ , u x , t = 0 , x , t ∈ ∂ S × 0 , + ∞ , u x , 0 = u 0 ≥ 0 ( n o n t r i v i a l ) , x ∈ S ¯ on a discrete network S . In fact, it will be seen that the condition (C) improves the conditions known so far. [ABSTRACT FROM AUTHOR]

The advantage of examining causality from the perspective of modelling is thus that it puts us naturally closer to the practice of the sciences. This means being able to set up an interdisciplinary dialogue that contrasts and compares modelling practices in different fields, say economics and biology, medicine and statistics, climate change and physics. It also means that it helps philosophers looking for questions that go beyond the narrow 'what-is-causality' or 'what-are-relata' and thus puts causality right at the centre of a complex crossroad: epistemology/methodology, metaphysics, politics/ethics. This special issue collects nine papers that touch upon various scientific fields, from system biology to medicine to quantum mechanics to economics, and different questions, from explanation and prediction to the role of both true and false assumptions in modelling. [ABSTRACT FROM AUTHOR]

Brazilian guidelines for high school and several studies conducted in different countries have shown the importance of working in physics education the interrelations between the subject radiations and aspects of medicine/health. Thus, in order to understand how the literature of physics/science education area has addressed such relationships, we review papers published in 24 national and international journals, in two Brazilian conference proceedings (EPEFs and SNEFs) and in dissertations and theses produced in Brazilian graduate programs. We found 31 studies, four in EPEFs, fourteen in SNEFs, four in the journal Physics Education, one in the journal International Journal of Science Education, one in the journal Research in Science & Technological Education, one in the journal The Physics Teacher, one in the Brazilian journal Ensaio: Pesquisa em Educação em Ciências and five master's dissertations produced in the following universities: UFRGS, UFRJ, Unicamp and USP. In addition to synthesize each of the selected works, we systematize their contributions in three categories: I) Justifications for the teaching of radiations and specially to relate them to aspects of medicine/health; II) Considerations about didactic resources to address the issue; and III) Considerations about the results obtained from the application of educational proposals. We conclude that although the reviewed literature offers interesting contributions, there is still lack of empirical research on the subject. [ABSTRACT FROM AUTHOR]

Background: "Neglected Tropical Diseases" (NTDs) affect millions of people in Africa, Asia and South America. The two primary ways of strategic interventions are "preventive chemotherapy and transmission control" (PCT), and "innovative and intensified disease management" (IDM). In the last 5 years, phenomenal progress has been achieved. However, it is crucial to intensify research effort into NTDs, because of the emerging drug resistance. According to the World Health Organization (WHO), the term NTDs covers 17 diseases, namely buruli ulcer, Chagas disease, dengue, dracunculiasis, echinococcosis, trematodiasis, human African trypanosomiasis, leishmaniasis, leprosy, lymphatic filariasis, onchocerciasis, rabies, schistosomiasis, soil-transmitted helminthes, taeniasis, trachoma, and yaws. The aim of this study is to map out research and development (R&D) landscape through patent analysis of these identified NTDs. To achieve this, analysis and evaluation have been conducted on patenting trends, current legal status of patent families, priority countries by earliest priority years and their assignee types, technological fields of patent families over time, and original and current patent assignees.Main Body: Patent families were extracted from Patseer, an international database of patents from over 100 patent issuing authorities worldwide. Evaluation of the patents was carried out using the combination of different search terms related to each identified NTD. In this paper, a total number of 12,350 patent families were analyzed. The main countries with sources of inventions were identified to be the United States (US) and China. The main technological fields covered by NTDs patent landscape are pharmaceuticals, biotechnology, organic fine chemistry, analysis of biological materials, basic materials chemistry, and medical technology. Governmental institutions and universities are the primary original assignees. Among the NTDs, leishmaniasis, dengue, and rabies received the highest number of patent families, while human African trypanosomiasis (sleeping sickness), taeniasis, and dracunciliasis received the least. The overall trend of patent families shows an increase between 1985 and 2008, and followed by at least 6 years of stagnation.Conclusion: The filing pattern of patent families analyzed undoubtedly reveals slow progress on research and development of NTDs. Involving new players, such as non-governmental organizations may help to mitigate and reduce the burden of NTDs. [ABSTRACT FROM AUTHOR]

Background: During the last 3 decades, Iran has experienced a rapid population growth and at the same time the health of Iranian people has improved greatly. This achievement was mainly due to training and availability of health manpower, well organized public health network and medical science and research improvement. In this article, we aimed to report the relevant data about the medical science and research situation in Iran and compare them with other countries. Methods: In this study, after reviewing science development and research indicators in medical sciences with participation of key stakeholders, we selected 3 main hybrid indexes consisting of "Research and Development (R&D) expenditures," "Personnel in Science and Technology sector" and "knowledge generation" for evaluation of medical science and research situation. Data was extracted from reliable databases. Results: Over the past decade, Iran has achieved significant success in medical sciences and for the first time in 2015 based on Scopus index, Iran ranked first in the number of published scientific papers and number of citations in the region and among all Islamic countries. Also, 2% of the world's publications belong to Iran. Regarding innovation, the number of Iranian patents submitted to the United States Patent and Trademark Office (USPTO) was 3 and 43 in 2008 and 2013, respectively. In these years, the number of personnel in science and technology sectors including post graduate students, researchers and academic members in universities of medical sciences (UMSs) have increased. The female students in medical sciences field account for about twothirds of all students. Also, women comprise about one-third of faculty members. Since 5 years ago, Iran has had growth in science and technology parks. These achievements were attained in spite of the fact that research spending in Iran was still very low (0.5% of gross domestic product [GDP]) due to economic hardships and sanctions. Conclusion: Medical science and research development has been at least partially due to health technological development, training and availability of health manpower and improvement of overall health status in Iran compared to other Islamic countries. [ABSTRACT FROM AUTHOR]

In this paper, an equivalent circuit model for nested split-ring resonators (NSRRs) is proposed. NSRRs are an emerging class of split ring resonators, preferred in a range of areas from sensing in biomedical or civil engineering applications to antenna design, due to their more compact size and enhanced sensitivity/resolution characteristics over the conventional SRRs. In the proposed model, the NSRR structure is treated as a combination of basic elements, i.e., strips and gaps, and the electromagnetic characteristics of the whole geometry are expressed in terms of capacitances and inductances of each of these elements. The outputs of the model are compared with those obtained via full-wave simulations using the package programs as well as measurements. The variation of NSRR resonance frequency ( f\text {res} ) with all important design parameters is also compared with full-wave simulations. In all comparisons, the results demonstrate agreement, showing that the proposed model can correctly explain the electromagnetics of the NSRR structure and that it provides an intuitive way for a better and easier analysis and a preliminary design of normally complex structures. [ABSTRACT FROM AUTHOR]

Micro/nanomotors (MNMs) that could perform diverse tasks are the most dynamic research areas in nanoscience and nanotechnology. Up to now, the majority of micromotors contain the precious metal platinum (Pt) as the catalyst for propulsion. The high cost and scarcity of Pt seriously impede its practical application. The exploration of manganese oxide based MNMs provides a route to circumstance the drawbacks of Pt. In this paper, graphene/MnO 2 microtubes as a highly efficient micromotor was fabricated by a template-assisted electrochemical process. The resulted micromotors show a good motion behavior in a wide range of hydrogen peroxide (H 2 O 2 ) concentrations. Owing to its robust motion, easy functionalization, a large quantity of surface functional groups for modification, and simple synthesis, these fine micromotors hold a great promise for biomedicine and environmental applications. [ABSTRACT FROM AUTHOR]

Responsive hydrogels have been extensively studied in the past decades because they are able to interact with their biological environment in a pre-programmed manner. Several biomedical applications have already been achieved (or at least approached) by in vivo experiments. As a class, injectable hydrogels gained considerable attention because of their minimally invasive implantation. However, the final shaping of hydrogel implants is not resolved, and their lifetime is limited because of their insufficient mechanical stability. The solution to these challenges can be given by two seemingly independent properties, shape memory and self-healing. Both properties are well-known for conventional polymers but research on the shape memory or self-healing of hydrogels is in its infancy. In this study, we introduce the molecular mechanisms behind these two properties with a focus on hydrogels, attempt to provide a general overview on the role of reversible physical and chemical interactions, and discuss the similarities between the background of shape memory and self-healing. There are a number of open questions regarding the uniform characterisation of such hydrogels, and their theoretical description is very incomplete, but the developed systems hold great promise for future applications. In the final part of the paper, we note that the synthesis of hydrogels providing both self-healing and shape memory is a difficult challenge, but some examples do exist. Future research in these fields should focus on a better understanding of structure-property correlations and should uncover additional fields of application for these advanced materials. [ABSTRACT FROM AUTHOR]

Q-learning is a method of reinforcement learning that employs backwards stagewise estimation to identify sequences of actions that maximize some long-term reward. The method can be applied to sequential multipleassignment randomized trials to develop personalized adaptive treatment strategies (ATSs)--longitudinal practice guidelines highly tailored to time-varying attributes of individual patients. Sometimes, the basis for choosing which ATSs to include in a sequential multiple-assignment randomized trial (or randomized controlled trial) may be inadequate. Nonrandomized data sources may inform the initial design of ATSs, which could later be prospectively validated. In this paper, we illustrate challenges involved in using nonrandomized data for this purpose with a case study from the Center for International Blood and Marrow Transplant Research registry (1995--2007) aimed at 1) determining whether the sequence of therapeutic classes used in graft-versus-host disease prophylaxis and in refractory graft-versus-host disease is associated with improved survival and 2) identifying donor and patient factors with which to guide individualized immunosuppressant selections over time. We discuss how to communicate the potential benefit derived from following an ATS at the population and subgroup levels and how to evaluate its robustness to modeling assumptions. This worked example may serve as a model for developing ATSs from registries and cohorts in oncology and other fields requiring sequential treatment decisions. [ABSTRACT FROM AUTHOR]

The Gorgias is frequently read as a dialogue in which Socrates fails to convince especially his last interlocutor Callicles to adopt a philosophical way of life. Instead, Callicles becomes increasingly indignant about the repeated refutation of his personal convictions and eventually refuses to participate in the conversation any longer. In general scholars explain this result by Callicles' recalcitrance. It is supposed that the dialogue illustrates the impossibility of persuasion if an interlocutor refuses to cooperate - which would imply certain limitations of the Socratic elenchus. In contrast, this paper demonstrates that Socrates indeed achieves his aim of shaking Callicles' faith. By decoding the medicine and court imagery, ubiquitous throughout the whole dialogue, it will be argued that, far from being an illustration of failure, the text instead indicates that Socrates' conversation with Callicles is successful - and thus proves the efficacy of the elenctic method even on reluctant opponents. [ABSTRACT FROM AUTHOR]

This paper has in part emerged from work recently undertaken by Parker and Pant under a British Academy funded Small Grant examining the phenomenon of aging in Nepal. This has enabled them to work in collaboration with the Nepal School of Social Work in Kathmandu to both generate locally relevant empirical research on aging and to facilitate the creation of spaces for dialogue on the implications of aging in Nepal. As a result of this project a network of key academics, activists, government policy makers and non-government organizations, both national and international, has been formed. The findings of this study reveal a lack of both empirical data and theoretical development on aging in Nepal. Aging in the west is often viewed from a biomedical perspective where the emphasis is on medical treatment and health and social care arrangements. Biomedicine also dominates international health strategies, organizations, and the funding streams for aid, of which Nepal is a recipient. Whilst longevity is clearly a positive outcome of development, it also presents health and social care dilemmas. This paper provides an opportunity to explore some of these key issues and highlights the need for practitioners, policy makers and the research community in Nepal to provide an open dialogue in which local, culturally appropriate decisions can be developed in the best interest of older people in Nepal. [ABSTRACT FROM AUTHOR]

Background: We sought to analyze the growing worldwide trends of intracranial aneurysm research, investigate China's recent contribution, and compare the contributions of mainland China, Taiwan, and Hong Kong. Methods: Global and China intracranial aneurysm-related publications were retrieved from the Web of Science database from 1991 to 2012. Excel 2007, Matlab, and Thomson Data Analyzer (TDA) software were used to analyze the search results for number of publications, cited frequency, h-index, and organization contributions. Results: 16468 global papers were identified that were cited 273500 times until 2013-08-15. The United States accounted for 31.497% of the articles, 58.64% of the citations, and the highest h-index (127). Japan and Germany followed in frequency. China's articles ranked eighth (third in 2012) in total number, with most of the contributions occurring since 2002 (91.33%). China was at the early stage of the logic growth curve (exponential growth), with the citation frequency and h-index per year increasing. The quality of the publications was low. The main research centers were located in Beijing, Shanghai, Taiwan, and Hong Kong. The main Asian funding body was the National Natural Science Foundation of China. The number of publications and frequency of citations of papers from mainland China was greater than that of Taiwan or Hong Kong. Conclusion: Global intracranial aneurysm research has been developing swiftly since 1991, with the United States making the largest contribution. Research in China started later, in 2002. Since then, China has increased its rate of publication, and became the third largest contributor by 2012. [ABSTRACT FROM AUTHOR]

Objectives: This paper examines the ethnic and gender differentials in high blood pressure (HBP), diabetes, coronary heart disease (CHD), arthritis and asthma among older people in Malaysia, and how these diseases along with other factors affect self-rated health. Differentials in the prevalence of non-communicable diseases among older people are examined in the context of socio-cultural perspectives in multi-ethnic Malaysia. Methods: Data for this paper are obtained from the 2004 Malaysian Population and Family Survey. The survey covered a nationally representative sample of 3,406 persons aged 50 and over, comprising three main ethnic groups (Malays, Chinese and Indians) and all other indigenous groups. Bivariate analyses and hierarchical logistic regression were used in the analyses. Results: Arthritis was the most common non-communicable disease (NCD), followed by HBP, diabetes, asthma and CHD. Older females were more likely than males to have arthritis and HBP, but males were more likely to have asthma. Diabetes and CHD were most prevalent among Indians, while arthritis and HBP were most prevalent among the Indigenous groups. Older people were more likely to report poor health if they suffered from NCD, especially CHD. Controlling for socio-economic, health and lifestyle factors, Chinese were least likely to report poor health, whereas Indians and Indigenous people were more likely to do so. Chinese that had HBP were more likely to report poor health compared to other ethnic groups with the same disease. Among those with arthritis, Indians were more likely to report poor health. Conclusion: Perceived health status and prevalence of arthritis, HBP, diabetes, asthma and CHD varied widely across ethnic groups. Promotion of healthy lifestyle, early detection and timely intervention of NCDs affecting different ethnic groups and gender with socio-cultural orientations would go a long way in alleviating the debilitating effects of the common NCDs among older people. [ABSTRACT FROM AUTHOR]

Background: Augmentative and Alternative Communication (AAC) is used for treating children with severe disorders of speech-language production and/or comprehension. Various strategies are used, but research and debate on their efficacy have remained limited to a specific area and have rarely reached the general medical community. Objective: To systematically evaluate outcomes of AAC interventions in children with limited speech or language skills. Methods: Searches were conducted (up to December 2012) in the MEDLINE, EMBASE, PsycINFO, CINAHL, DARE, and Cochrane Library databases. Furthermore, relevant journals were searched by hand. References from identified studies were examined. Only RCTs were considered. Trial quality was assessed according to a standardized and validated set of criteria. Results: Fourteen of 1661 retrieved papers met inclusion criteria. A total of 666 children were included in the review and 7 papers involved only children <5 years old. Papers were of average quality and all but one had been published during the previous 10 years by one of 8 research groups, 5 of which from the United States. Seven studies directly addressed AAC use by children with different disabilities. Seven studies enrolled typically developing children: 5 evaluated the use of AAC technologies by children without disabilities in order to obtain results that could be used to improve interventions in peers with disabilities, and 2 evaluated peers’ attitudes towards children who used AAC. Both interventions and outcome measures varied widely between studies. Overall findings demonstrate the effectiveness of the AAC interventions considered, but the focus on RCTs alone appears too restrictive. Conclusions: Solid evidence of the positive effects of AAC interventions in children with severe communication disorders must be generated, and different methods are needed besides RCTs. Moreover, it is important that knowledge, research, and debate extend to the medical community in order to ensure clinically effective AAC provision for these children (and their parents). [ABSTRACT FROM AUTHOR]

We report on the accuracy of using near-infrared spectroscopy (NIRS) to predict the age of Anopheles mosquitoes reared from wild larvae and a mixed age-wild adult population collected from pit traps after exposure to pyrethroids. The mosquitoes reared from wild larvae were estimated as <7 or ≥7 d old with an overall accuracy of 79%. The age categories of Anopheles mosquitoes that were not exposed to the insecticide papers were predicted with 78% accuracy whereas the age categories of resistant, susceptible and mosquitoes exposed to control papers were predicted with 82%, 78% and 79% accuracy, respectively. The ages of 85% of the wild-collected mixed-age Anopheles were predicted by NIRS as ≤8 d for both susceptible and resistant groups. The age structure of wild-collected mosquitoes was not significantly different for the pyrethroid-susceptible and pyrethroid-resistant mosquitoes (P = 0.210). Based on these findings, NIRS chronological age estimation technique for Anopheles mosquitoes may be independent of insecticide exposure and the environmental conditions to which the mosquitoes are exposed. [ABSTRACT FROM AUTHOR]

Background: Non-fatal self-harm is one of the most frequent reasons for emergency hospital admission and the strongest risk factor for subsequent suicide. Repeat self-harm and suicide are key clinical outcomes of the hospital management of self-harm. We have undertaken a comprehensive review of the international literature on the incidence of fatal and non-fatal repeat self-harm and investigated factors influencing variation in these estimates as well as changes in the incidence of repeat self-harm and suicide over the last 30 years. Methods and Findings: Medline, EMBASE, PsycINFO, Google Scholar, article reference lists and personal paper collections of the authors were searched for studies describing rates of fatal and non-fatal self-harm amongst people who presented to health care services for deliberate self-harm. Heterogeneity in pooled estimates of repeat self-harm incidence was investigated using stratified meta-analysis and meta-regression. The search identified 177 relevant papers. The risk of suicide in the 12 months after an index attempt was 1.6% (CI 1.2–2.4) and 3.9% (CI 3.2–4.8) after 5 years. The estimated 1 year rate of non-fatal repeat self-harm was 16.3% (CI 15.1–17.7). This proportion was considerably lower in Asian countries (10.0%, CI 7.3–13.6%) and varies between studies identifying repeat episodes using hospital admission data (13.7%, CI 12.3–15.3) and studies using patient report (21.9%, CI 14.3–32.2). There was no evidence that the incidence of repeat self-harm was lower in more recent (post 2000) studies compared to those from the 1980s and 1990s. Conclusions: One in 25 patients presenting to hospital for self-harm will kill themselves in the next 5 years. The incidence of repeat self-harm and suicide in this population has not changed in over 10 years. Different methods of identifying repeat episodes of self-harm produce varying estimates of incidence and this heterogeneity should be considered when evaluating interventions aimed at reducing non-fatal repeat self-harm. [ABSTRACT FROM AUTHOR]

The study of individual differences encompasses broad constructs including intelligence, creativity, and personality. However, substantially less research is devoted to the study of specific aptitudes in spite of their importance to educational, occupational, and avocational success. We sought to determine subcortical brain structural correlates of several broad aptitudes including Math, Vocabulary, Foresight, Paper Folding, and Inductive Reasoning in a large (N = 107), healthy, young (age range  = 16–29) cohort. Subcortical volumes were measured using an automated technique (FreeSurfer) across structures including bilateral caudate, putamen, globus pallidus, thalamus, nucleus accumbens, hippocampus, amygdala, and five equal regions of the corpus callosum. We found that performance on measures of each aptitude was predicted by different subcortical structures: Math – higher right nucleus accumbens volume; Vocabulary – higher left hippocampus volume; Paper Folding – higher right thalamus volume; Foresight – lower right thalamus and higher mid anterior corpus callosum volume; Inductive Reasoning – higher mid anterior corpus callosum volume. Our results support general findings, within the cognitive neurosciences, showing lateralization of structure-function relationships, as well as more specific relationships between individual structures (e.g., left hippocampus) and functions relevant to particular aptitudes (e.g., Vocabulary). [ABSTRACT FROM AUTHOR]

Introduction: Role of vaginal sex in heterosexual transmission of HIV has been investigated but that of heterosexual anal sex (HAS) is not fully understood. This paper examines practice of HAS among Female Sex Workers (FSWs) and its correlates in India where the HIV epidemic is being primarily driven by core groups like FSWs. Methods: Data for this paper are drawn from Round I survey of 9667 FSWs in the Integrated Biological and Behavioral Assessment (IBBA) from 23 districts of 4 high HIV prevalent states of India. Bivariate and multivariate analysis identified factors associated with HAS. Results: Ever having anal sex was reported by 11.9% FSWs (95% CI: 11.3%–12.6%). Typology (AOR 2.20, 95% CI 1.64–2.95) and literacy (AOR 1.28, 95% CI 1.10–1.49) were positively associated with practice of HAS. Longer duration in sex trade (AOR 1.69, 95% CI 1.44–1.99), entertaining larger number of clients the previous week (AOR 1.78, 95% CI 1.47–2.15), alcohol consumption (AOR 1.21, 95% CI 1.03–1.42) and inability to negotiate condom use (AOR 1.53, 95% CI 1.28–1.83) were also correlated with HAS. Self-risk perception for HIV (AOR 1.46, 95% CI 1.25–1.71) did not impede HAS. Although symptoms of sexually transmitted infections (STIs) in the last 12 months were associated with anal sex (AOR 1.39, 95% CI 1.13–1.72) there was no significant association between laboratory confirmed HIV and other STIs with HAS. Conclusion: Practice of HAS by FSWs might significantly contribute to HIV transmission in India. This study also shows that despite self-risk perception for HIV, even literate FSWs with longer duration in sex work report HAS. General messages on condom use may not influence safe HAS. FSWs need to be targeted with specific messages on HIV transmission during anal sex. Women controlled prevention methods, such as rectal microbicides and vaginal microbicides are needed. [ABSTRACT FROM AUTHOR]

In a stratified analysis, the results from different strata if homogeneity assumption is met are pooled together to obtain a single summary estimate for the common effect parameter. However, the effect can appear homogeneous across strata using one measure but heterogeneous using another. Consequently, two researchers analyzing the same data can arrive at conflicting conclusions if they use different effect measures. In this paper, the author draws on the sufficient component cause model to develop a stratified-analysis method regarding a particular effect measure, the ‘peril ratio’. When there is no mechanistic interaction between the exposure under study and the stratifying variable (i.e., when they do not work together to complete any sufficient cause), the peril ratio is constant across strata. The author presents formulas for the estimation of such a common peril ratio. Three real data are re-analyzed for illustration. When the data is consistent with peril-ratio homogeneity in a stratified analysis, researchers can use the formulas in this paper to pool the strata. [ABSTRACT FROM AUTHOR]

Constraints arise naturally in many scientific experiments/studies such as in, epidemiology, biology, toxicology, etc. and often researchers ignore such information when analyzing their data and use standard methods such as the analysis of variance (ANOVA). Such methods may not only result in a loss of power and efficiency in costs of experimentation but also may result poor interpretation of the data. In this paper we discuss constrained statistical inference in the context of linear mixed effects models that arise naturally in many applications, such as in repeated measurements designs, familial studies and others. We introduce a novel methodology that is broadly applicable for a variety of constraints on the parameters. Since in many applications sample sizes are small and/or the data are not necessarily normally distributed and furthermore error variances need not be homoscedastic (i.e. heterogeneity in the data) we use an empirical best linear unbiased predictor (EBLUP) type residual based bootstrap methodology for deriving critical values of the proposed test. Our simulation studies suggest that the proposed procedure maintains the desired nominal Type I error while competing well with other tests in terms of power. We illustrate the proposed methodology by re-analyzing a clinical trial data on blood mercury level. The methodology introduced in this paper can be easily extended to other settings such as nonlinear and generalized regression models. [ABSTRACT FROM AUTHOR]

The local neighborhood forms an integral part of our lives. It provides the context through which social networks are nurtured and the foundation from which a sense of attachment and cohesion with fellow residents can be established. Whereas much of the previous research has examined the role of social and demographic characteristic in relation to the level of neighboring and cohesion, this paper explores whether particular environmental features in the neighborhood affect social porosity. We define social porosity as the degree to which social ties flow over the surface of a neighborhood. The focus of our paper is to examine the extent to which a neighborhood's environmental features impede the level of social porosity present among residents. To do this, we integrate data from the census, topographic databases and a 2010 survey of 4,351 residents from 146 neighborhoods in Australia. The study introduces the concepts of wedges and social holes. The presence of two sources of wedges is measured: rivers and highways. The presence of two sources of social holes is measured: parks and industrial areas. Borrowing from the geography literature, several measures are constructed to capture how these features collectively carve up the physical environment of neighborhoods. We then consider how this influences residents' neighboring behavior, their level of attachment to the neighborhood and their sense of neighborhood cohesion. We find that the distance of a neighborhood to one form of social hole–industrial areas–has a particularly strong negative effect on all three dependent variables. The presence of the other form of social hole–parks–has a weaker negative effect. Neighborhood wedges also impact social interaction. Both the length of a river and the number of highway fragments in a neighborhood has a consistent negative effect on neighboring, attachment and cohesion. [ABSTRACT FROM AUTHOR]

A growing number of studies examine instructional training and brain activity. The purpose of this paper is to review the literature regarding neuroimaging of reading intervention, with a particular focus on reading difficulties (RD). To locate relevant studies, searches of peer-reviewed literature were conducted using electronic databases to search for studies from the imaging modalities of fMRI and MEG (including MSI) that explored reading intervention. Of the 96 identified studies, 22 met the inclusion criteria for descriptive analysis. A subset of these (8 fMRI experiments with post-intervention data) was subjected to activation likelihood estimate (ALE) meta-analysis to investigate differences in functional activation following reading intervention. Findings from the literature review suggest differences in functional activation of numerous brain regions associated with reading intervention, including bilateral inferior frontal, superior temporal, middle temporal, middle frontal, superior frontal, and postcentral gyri, as well as bilateral occipital cortex, inferior parietal lobules, thalami, and insulae. Findings from the meta-analysis indicate change in functional activation following reading intervention in the left thalamus, right insula/inferior frontal, left inferior frontal, right posterior cingulate, and left middle occipital gyri. Though these findings should be interpreted with caution due to the small number of studies and the disparate methodologies used, this paper is an effort to synthesize across studies and to guide future exploration of neuroimaging and reading intervention. [ABSTRACT FROM AUTHOR]

As non-canonical texts, apocryphal prayers had been exposed to various influences, and thus became the most comprehensive written records of the interaction between medical knowledge on one hand, and folk and religious medicine on the other hand. This paper examines apocryphal prayers used to heal illnesses and acute conditions. By analyzing the selected examples of apocryphal prayers, such as against nežit (various inflammatory conditions thought to be caused by an evil spirit of this name), against toothache, against nosebleed, against snake bites, against bites by rabid dogs or wolves, the paper determines their characteristics. On one hand, the paper identifies medical knowledge appearing in the prayers and delineates ways in which the cause of an illness and the proper course of treatment are determined. On the other hand, apocryphal prayers are examined within a framework used for literary text analysis, which results in a consideration of their stylistic values. [ABSTRACT FROM AUTHOR]

This paper places 'Islam and bioethics' within the framework of 'religion and science' discourse. It thus may be seen as a complement to the paper by Henk ten Have () with which this thematic section in Zygon: Journal of Religion and Science opens, which places 'Islam and bioethics' in the context of contemporary bioethics. It turns out that in Zygon there have been more submitted articles on Islam and bioethics than on any other Islam-related topic. This may be a consequence of the global nature of the bioethical issues, driven by advancement in science and technology, which allows for conversation across cultural and religious boundaries even when the normative references and argumentative methods are tradition-specific. [ABSTRACT FROM AUTHOR]

Prof. Dr. Gheorghe Bilaşcu (1863-1926) was one of the founders of the Romanian Faculty of Medicine in Cluj. At this Faculty, in 1919/1920 he created the department and the clinic of dentistry. These two achievements were accomplished for the first time in Romania. Normally, his contribution should have been appreciated both during his life and after his death. Also, his name would be expected to be present in the large majority of Romanian medico-historians dictionaries, treatises, papers etc. Unfortunately, his posthumous appreciation was not as Bilaşcu would have deserved. In our paper we present the recognition of Gh. Bilaşcu's contributions in the Romanian history of dentistry between 1926-2013. We divided this period into three intervals: from 1926 to 1948, the communist era, and after the anticommunist revolution (1990-present). In the first interval the achievements of Bilaşcu in the field of dentistry were very much appreciated and they were mentioned in a correct way in different medico-historical sources of information. During the communist era the name of Bilaşcu was omitted in some dictionaries, courses etc. After 1990, the important role of Bilaşcu in Romanian dentistry was put into its important place in the majority of Romanian history of medicine sources of information. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the profile and the scientific production of researchers in Pediatrics with scholarship from the National Counsel of Technological and Scientific Development. Methods: The Lattes curricula of 34 researchers in Pediatrics with active scholarships, from 2006 to 2008 were included in the analysis. The variables of interest were: gender, affiliation, time since PHD, tutoring of undergraduate students, mentorship of masters and doctors, scientific production and the papers' impact. Results: In a total of 411 researchers in Medicine, 34 (8%) belonged to Pediatrics. Males (77%) and scholars in the category 2 of productivity (62%) prevailed. Three states of Brazil were responsible for approximately 90% of the researchers: São Paulo (53%), Minas Gerais (21%), and Rio Grande do Sul (15%). During their academic career, the Pediatrics researchers have published 3,122 articles with a median of 89 articles per researcher (interquartile range - IQ=51-119). Of the total, 40 and 59% articles were indexed in the Web of Science and Scopus databases, respectively. The Pediatrics researchers have published papers in 599 journals with a median impact factor of 2.35 (IQ=1.37-3.73) for the 323 indexed journals. Conclusions: The Pediatrics researchers have a relevant scientific output from the quantity point of the view, but there is a need to improve quality. [ABSTRACT FROM AUTHOR]

Background: Finding duplicates is an important phase of systematic review. However, no consensus regarding the methods to find duplicates has been provided. This study aims to describe a pragmatic strategy of combining auto- and hand-searching duplicates in systematic review and to evaluate the prevalence and characteristics of duplicates. Methods and Findings: Literatures regarding portal vein thrombosis (PVT) and Budd-Chiari syndrome (BCS) were searched by the PubMed, EMBASE, and Cochrane library databases. Duplicates included one index paper and one or more redundant papers. They were divided into type-I (duplicates among different databases) and type-II (duplicate publications in different journals/issues) duplicates. For type-I duplicates, reference items were further compared between index and redundant papers. Of 10936 papers regarding PVT, 2399 and 1307 were identified as auto- and hand-searched duplicates, respectively. The prevalence of auto- and hand-searched redundant papers was 11.0% (1201/10936) and 6.1% (665/10936), respectively. They included 3431 type-I and 275 type-II duplicates. Of 11403 papers regarding BCS, 3275 and 2064 were identified as auto- and hand-searched duplicates, respectively. The prevalence of auto- and hand-searched redundant papers was 14.4% (1640/11403) and 9.1% (1039/11403), respectively. They included 5053 type-I and 286 type-II duplicates. Most of type-I duplicates were identified by auto-searching method (69.5%, 2385/3431 in PVT literatures; 64.6%, 3263/5053 in BCS literatures). Nearly all type-II duplicates were identified by hand-searching method (94.9%, 261/275 in PVT literatures; 95.8%, 274/286 in BCS literatures). Compared with those identified by auto-searching method, type-I duplicates identified by hand-searching method had a significantly higher prevalence of wrong items (47/2385 versus 498/1046, p<0.0001 in PVT literatures; 30/3263 versus 778/1790, p<0.0001 in BCS literatures). Most of wrong items originated from EMBASE database. Conclusion: Given the inadequacy of a single strategy of auto-searching method, a combined strategy of auto- and hand-searching methods should be employed to find duplicates in systematic review. [ABSTRACT FROM AUTHOR]

Background: The practice of giving certain authors equal credit in original research publications was increasingly common in some specialty. This study aimed to investigate the prevalence and characteristics of designating some authors with equally credited authors (ECAs) in major anaesthesia journals. Methodology/Principal Findings: The practice of giving authors equal credit was searched and identified in the three major anaesthesia journals between January 1, 2002 and December 31, 2011. Papers with ECAs had a higher proportion of the total number of articles in 2011 versus published in 2002 (Anesthesiology, 8.8% vs. 0.9%; British Journal of Anaesthesia, 8.8% vs. 0%; Anesthesia & Analgesia, 3.4% vs. 0.3%; totally, 6.4% vs. 0.4%). A significant increasing trend in annual proportion of articles with ECA was found in the three journals. The first two authors listed in the byline had equal credit in most cases. Conclusions/Significance: The practice of giving authors equal credit in original research papers is increasingly common in major anaesthesia journals. It may be warranted for the journals to guide the authors how to regard this practice. [ABSTRACT FROM AUTHOR]

Objective: The Hospital Anxiety and Depression Scale (HADS) is widely used to screen for anxiety and depression. A large literature is citable in support of its validity, but difficulties are increasingly being identified, such as inexplicably discrepant optimal cutpoints and inconsistent factor-structures. This article examines whether these problems could be due to the construction of the HADS that poses difficulties for translation and cross-cultural use. Methods: Authors’ awareness of difficulties translating the HADS were identified by examining 20% of studies using the HADS, obtained by a systematic literature search in Pubmed and PsycINFO in May 2012. Reports of use of translations and validation studies were recorded for papers from non-English speaking countries. Narrative and systematic reviews were examined for how authors dealt with different translations. Results: Of 417 papers from non-English speaking countries, only 45% indicated whether a translation was used. Studies validating translations were cited in 54%. Seventeen reviews, incorporating data from diverse translated versions, were examined. Only seven mentioned issues of language and culture, and none indicated insurmountable problems in integrating results from different translations. Conclusion: Initial decisions concerning item content and response options likely leave the HADS difficult to translate, but we failed to find an acknowledgment of problems in articles involving its translation and cross-cultural use. Investigators’ lack of awareness of these issues can lead to anomalous results and difficulties in interpretation and integration of these results. Reviews tend to overlook these issues and most reviews indiscriminately integrate results from studies performed in different countries. Cross-culturally valid, but literally translated versions of the HADS may not be attainable, and specific cutpoints may not be valid across cultures and language. Claims about rates of anxiety and depression based on integrating cross-cultural data or using the same cutpoint across languages and culture should be subject to critical scrutiny. [ABSTRACT FROM AUTHOR]

Introduction: Respondent-driven sampling (RDS) offers a recruitment strategy for hard-to-reach populations. However, RDS faces logistical and theoretical challenges that threaten efficiency and validity in settings worldwide. We present innovative adaptations to conventional RDS to overcome barriers encountered in recruiting a large, representative sample of men who have sex with men (MSM) who travel internationally. Methods: Novel methodological adaptations for the “International Travel Research to Inform Prevention” or “I-TRIP” study were offering participants a choice between electronic and paper coupons referrals for recruitment and modifying the secondary incentives structure from small cash amounts to raffle entries for periodic large cash prize raffle drawings. Staged referral limit increases from 3 to 10 referrals and progressive addition of 70 seeds were also implemented. Results: There were 501 participants enrolled in up to 13 waves of growth. Among participants with a choice of referral methods, 81% selected electronic referrals. Of participants who were recruited electronically, 90% chose to remain with electronic referrals when it was their turn to recruit. The mean number of enrolled referrals was 0.91 for electronic referrals compared to 0.56 for paper coupons. Median referral lag time, i.e., the time interval between when recruiters were given their referrals and when a referred individual enrolled in the study, was 20 days (IQR 10–40) for electronic referrals, 20 days (IQR 8–58) for paper coupons, 20 days (IQR 10–41) for raffle entries and 33 days (IQR 16–148) for small cash incentives. Conclusions: The recruitment of MSM who travel internationally required maximizing known flexible tools of RDS while at the same time necessitating innovations to increase recruitment efficiency. Electronic referrals emerged as a major advantage in recruiting this hard-to-reach population who are of high socio-economic status, geographically diffuse and highly mobile. These enhancements may improve the performance of RDS in target populations with similar characteristics. [ABSTRACT FROM AUTHOR]

Background: More than two-thirds of the world's HIV-positive individuals live in sub-Saharan Africa, where genetic susceptibility to kidney disease is high and resources for kidney disease screening and antiretroviral therapy (ART) toxicity monitoring are limited. Equations to estimate glomerular filtration rate (GFR) from serum creatinine were derived in Western populations and may be less accurate in this population. Methods: We compared results from published GFR estimating equations with a direct measure of GFR by iohexol clearance in 99 HIV-infected, ART-naïve Kenyan adults. Iohexol concentration was measured from dried blood spots on filter paper. The bias ratio (mean of the ratio of estimated to measured GFR) and accuracy (percentage of estimates within 30% of the measured GFR) were calculated. Results: The median age was 35 years, and 60% were women. The majority had asymptomatic HIV, with median CD4+ cell count of 355 cells/mm3. Median measured GFR was 115 mL/min/1.73 m2. Overall accuracy was highest for the Chronic Kidney Disease Epidemiology Consortium (CKD-EPI) equation. Consistent with a prior report, bias and accuracy were improved by eliminating the coefficient for black race (85% of estimates within 30% of measured GFR). Accuracy of all equations was poor in participants with GFR 60–90 mL/min/1.73 m2 (<65% of estimates within 30% of measured GFR), although this subgroup was too small to reach definitive conclusions. Conclusions: Overall accuracy was highest for the CKD-EPI equation. Eliminating the coefficient for race further improved performance. Future studies are needed to determine the most accurate GFR estimate for use in individuals with GFR <90 mL/min/1.73 m2, in whom accurate estimation of kidney function is important to guide drug dosing. Direct measurement of GFR by iohexol clearance using a filter paper based assay is feasible for research purposes in resource-limited settings, and could be used to develop more accurate GFR estimates in African populations. [ABSTRACT FROM AUTHOR]