bluuebunny/crossref_metadata_2025 huggingface dataset:
New estimates of ongoing sea level change and land movements caused by Glacial Isostatic Adjustment in the Mediterranean region
Authors: Spada Giorgio , Melini Daniele
Published: December 2021

Glacial Isostatic Adjustment (GIA) caused by the melting of past ice sheets is still a major cause of sea level variations and 3-D crustal deformation in the Mediterranean region. However, since the contribution of GIA cannot be separated from those of oceanic or tectonic origin, its role can be only assessed by numerical modelling, solving the gravitationally self-consistent sea level equation. Nonetheless, uncertainties about the melting history of the late-Pleistocene ice sheets and the rheological profile of the Earth’s mantle affect the GIA predictions by an unknown amount. Estimating the GIA modelling uncertainties would be particularly important in the Mediterranean region, due to the amount of high quality geodetic data from space-borne and ground-based observations currently available, whose interpretation demands a suitable isostatic correction. Here we first review previous results about the effects of GIA in the Mediterranean Sea, enlightening the variability of all the fields affected by the persistent condition of isostatic disequilibrium. Then, for the first time in this region, we adopt an ensemble modelling approach to better constrain the present-day GIA contributions to sea level rise and geodetic variations, and their uncertainty.
Learning stochastic closures using ensemble Kalman inversion
Authors: Schneider Tapio , Stuart Andrew M , Wu Jin-Long
Published: December 2021

Although the governing equations of many systems, when derived from first principles, may be viewed as known, it is often too expensive to numerically simulate all the interactions they describe. Therefore, researchers often seek simpler descriptions that describe complex phenomena without numerically resolving all the interacting components. Stochastic differential equations (SDEs) arise naturally as models in this context. The growth in data acquisition, both through experiment and through simulations, provides an opportunity for the systematic derivation of SDE models in many disciplines. However, inconsistencies between SDEs and real data at short time scales often cause problems, when standard statistical methodology is applied to parameter estimation. The incompatibility between SDEs and real data can be addressed by deriving sufficient statistics from the time-series data and learning parameters of SDEs based on these. Here, we study sufficient statistics computed from time averages, an approach that we demonstrate to lead to sufficient statistics on a variety of problems and that has the secondary benefit of obviating the need to match trajectories. Following this approach, we formulate the fitting of SDEs to sufficient statistics from real data as an inverse problem and demonstrate that this inverse problem can be solved by using ensemble Kalman inversion. Furthermore, we create a framework for non-parametric learning of drift and diffusion terms by introducing hierarchical, refinable parameterizations of unknown functions, using Gaussian process regression. We demonstrate the proposed methodology for the fitting of SDE models, first in a simulation study with a noisy Lorenz ’63 model, and then in other applications, including dimension reduction in deterministic chaotic systems arising in the atmospheric sciences, large-scale pattern modeling in climate dynamics and simplified models for key observables arising in molecular dynamics. The results confirm that the proposed methodology provides a robust and systematic approach to fitting SDE models to real data.
Towards virtual modelling environments for functional–structural plant models based on Jupyter notebooks: application to the modelling of mango tree growth and development
Authors: Vaillant Jan , Grechi Isabelle , Normand Frédéric , Boudon Frédéric
Published: December 2021

Functional–structural plant models (FSPMs) are powerful tools to explore the complex interplays between plant growth, underlying physiological processes and the environment. Various modelling platforms dedicated to FSPMs have been developed with limited support for collaborative and distributed model design, reproducibility and dissemination. With the objective to alleviate these problems, we used the Jupyter project, an open-source computational notebook ecosystem, to create virtual modelling environments for plant models. These environments combined Python scientific modules, L-systems formalism, multidimensional arrays and 3D plant architecture visualization in Jupyter notebooks. As a case study, we present an application of such an environment by reimplementing V-Mango, a model of mango tree development and fruit production built on interrelated processes of architectural development and fruit growth that are affected by temporal, structural and environmental factors. This new implementation increased model modularity, with modules representing single processes and the workflows between them. The model modularity allowed us to run simulations for a subset of processes only, on simulated or empirical architectures. The exploration of carbohydrate source–sink relationships on a measured mango branch architecture illustrates this possibility. We also proposed solutions for visualization, distant distributed computation and parallel simulations of several independent mango trees during a growing season. The development of models on locations far from computational resources makes collaborative and distributed model design and implementation possible, and demonstrates the usefulness and efficiency of a customizable virtual modelling environment.
Designing COVID-19 vaccine mandates in colleges and universities: a roadmap to the 10 key questions
Authors: Wolf Susan M , Hodge James G
Published: December 2021

COVID-19 transmission among students, faculty, and staff at US institutions of higher education (IHEs) is a pressing concern, especially with the dominance of the highly contagious Delta variant and emergence of the Omicron variant. From the start of the pandemic to May 26, 2021, >700,000 cases were linked to US colleges and universities. To protect their populations and surrounding communities, IHE administrators are increasingly considering COVID-19 vaccine requirements. Roughly one-quarter of the nearly 4,000 college and university campuses across the US have announced COVID-19 vaccine mandates for students or employees. However, deciding to require vaccination is only the first of multiple decisions, as IHEs face complex issues of how to design and refine their mandates, including whether to require boosters. Mandates vary significantly in stringency, implementation, impact on members of the college or university community, and net benefit to the institution. This essay examines 10 key questions that an IHE must face in designing or refining a COVID-19 vaccination mandate. Showing that these 10 questions were carefully considered may be crucial if the institution's mandate is challenged. Ultimately, how an IHE designs its mandate may make the difference between meaningful risk mitigation that advances institutional goals and benefits students, faculty, and staff versus a public health failure that erodes trust, raises equity concerns, threatens to undermine preexisting vaccination requirements, and divides the campus.
Carnivores in color: pelt color patterns among carnivores in Idaho
Authors: Ausband David E , Krohner Jessica M
Published: December 2021

Pelt color serves many functions from signaling to crypsis to thermoregulation and its purpose has been a lively source of debate in biology for over a century. Determining the effects of both habitat and human influences on pelt color patterns can be difficult. We made novel use of a multispecies occupancy model by defining “pelt color” as “species.” We then used this model to test predictions and estimate pelt color patterns concurrently for three carnivore species in Idaho, United States. We predicted pelt patterns of all three carnivores would be affected by environmental variables as well as human disturbance. Areas of Idaho where baiting was allowed and preferential harvest possible did not explain pelt patterns in black bears and neither did forest cover. Road density was positively associated with detection probability but negatively associated with occupancy of both black and brown pelt bears, however. Gray pelt wolves were found more often in areas with higher road densities than black wolves. As predicted, black, but not gray, wolves were positively associated with forest cover. Both red and black pelt foxes were positively associated with increasing elevation and road density. Black pelt foxes were negatively associated with forest cover, mirroring the habitat use described for native black pelt foxes. We demonstrate how using noninvasively collected data and extending multispecies occupancy models can allow biologists to study the distribution of different pelt colors in wild populations.
Habitat and drought influence the diet of an unexpected mycophagist: fishers in the Sierra Nevada, California
Authors: Smith G Bradley , Tucker Jody M , Pauli Jonathan N
Published: December 2021

Climate change is creating hotter, drier, and more extreme weather. Weather anomalies such as extended drought along the Pacific Coast of North America are redefining ecosystems. In the Sierra Nevada mountains of California, an isolated, distinct and federally endangered population of fishers (Pekania pennanti) currently faces multiple threats. Severe drought, tree mortality, and megafires are reshaping the landscape in the southern Sierra with largely unknown effects on fisher ecology and conservation. Using hair collected during long-term population monitoring, we analyzed stable isotopes to quantify the diets of fishers before and after drought, and explored how habitat quality mediated the effect of drought on fisher diet. For the core population of fishers which occupy the northern and western portions of this region, their isotopic niche declined both in drought and in lower-quality habitats. Regardless of drought or habitat conditions, the summer diet of fishers here was dominated by fungi (47%), while little vertebrate mass (14%) was consumed. However, drought and habitat did influence consumption of plants and insects; fishers consumed more insects and less plants in drought conditions and in poorer habitat. In contrast, at the perennially dry, high-altitude Kern Plateau at the southeastern extent of their range, fishers predominantly consumed vertebrates (59%). Fishers show great plasticity in their diet, but the means and capacity for this flexibility is poorly understood. Retaining atypical diet items, notably fungi, and a diversity of forage in the Sierra Nevada could help to buffer the negative fitness costs from rapid environmental change for this endangered species.
Cryogenic electron microscopy approaches that combine images and tilt series
Authors: Calcraft Thomas , Rosenthal Peter B
Published: December 2021

Cryogenic electron microscopy can be widely applied to biological specimens from the molecular to the cellular scale. In single-particle analysis, 3D structures may be obtained in high resolution by averaging 2D images of single particles in random orientations. For pleomorphic specimens, structures may be obtained by recording the tilt series of a single example of the specimen and calculating tomograms. Where many copies of a single structure such as a protein or nucleic acid assembly are present within the tomogram, averaging of the sub-volumes (subtomogram averaging) has been successfully applied. The choice of data collection method for any given specimen may depend on the structural question of interest and is determined by the radiation sensitivity of the specimen. Here, we survey some recent developments on the use of hybrid methods for recording and analysing data from radiation-sensitive biological specimens. These include single-particle reconstruction from 2D images where additional views are recorded at a single tilt angle of the specimen and methods where image tilt series, initially used for tomogram reconstruction, are processed as individual single-particle images. There is a continuum of approaches now available to maximize structural information obtained from the specimen.
Near-infrared spectroscopy and HPLC combined with chemometrics for comprehensive evaluation of six organic acids in Ginkgo biloba leaf extract
Authors: Zhang Sijie , Gong Xingchu , Qu Haibin
Published: December 2021

Objectives

To investigate the feasibility of using near-infrared spectroscopy for rapid determination of main organic acids in Ginkgo biloba leaf extract (EGBL).

Methods

Main organic acids in EGBL were assayed using the HPLC method. Critical factors of the chromatographic separation were optimized by a novel analytical quality by design approach. Partial least squares-discriminant analysis (PLS-DA) was performed to screen the marker components, and principal component analysis (PCA) was utilized to distinguish the different samples. Then, spectral quantification potential was investigated using PLS and support vector machine (SVM) approaches. For modelling, different spectral preprocessing and wavelength selection methods were systematically compared.

Key findings

It was found that quinic acid, protocatechuic acid and 6-hydroxykynurenic acid were identified as possible index components. PLS-DA based on contents and PCA based on near-infrared spectra can both effectively distinguish the different EGBL samples. The calibration models with wonderful prediction performance can be both developed by the PLS and SVM algorithms.

Conclusions

NIR spectroscopy combined with chemometrics can realize the rapid and non-destructive qualitative and quantitative analysis of EGBL. The proposed method may be applied to quality control of EGBL and other natural products in commercial use.
Bilateral chylothorax following neck dissection on a child—Diagnosis and management in resource-limited settings: a case report
Authors: Misso Kennedy K , Elisante Joseph , Mganga Daniel , Poppe Vanessa , Tarmohammed Murad , Nkoronko Mugisha , Msuya David
Published: December 2021

Bilateral chylothorax is a rare complication following neck dissection, with fewer than thirty cases being reported over the last century. A serious life-threatening condition mostly encountered during thoracic procedures and dissections. In our case, conservative management resulted in complete resolution. We report a case of a 4-year-old child who underwent deep neck dissection due to recurrent hemangioma. She developed bilateral chylothorax and a conservative approach led to complete resolution.
Late-phase left ventricular pseudoaneurysm after three-time mitral valve surgery
Authors: Ishida Shinichi , Mutsuga Masato , Fujita Takashi , Yagami Kei
Published: December 2021

Rupture of the left ventricular posterior wall is a fatal complication during mitral valve replacement (MVR), and rupture mainly occurs intraoperatively and up to several days after MVR, but it rarely occurs in the late phase, such as several years postoperatively. Late rupture occasionally presents as left ventricular pseudoaneurysms (LVPAs). A 40-year-old man who had a three-time history of mitral valve surgery for infectious endocarditis was incidentally found to have a left ventricular aneurysm with no symptoms. He underwent closure of a LVPA with MVR. Although there are various surgical techniques to close LVPAs after mitral valve repair, it is still a challenging problem. Here, we report the case of a patient who successfully underwent LVPA repair with MVR and describe the technique.
Syndrome of inappropriate antidiuretic hormone secretion after functional endoscopic sinus surgery
Authors: Morosanu Cezar Octavian , Lee Keng Siang , Keshtkar Fatemeh , Langton-Hewer Claire
Published: December 2021

Functional endoscopic sinus surgery (FESS) is effective in cases of sinusitis where pharmacological treatment has not been successful. Patients undergoing FESS have reported an 85% improvement in symptoms as measured by the quality of life scores. Despite its convincing therapeutic benefit, complications sometimes occur with potentially dire consequences. We report the case of a 69-year-old patient who underwent FESS for recurrent frontal sinusitis and developed a syndrome of inappropriate antidiuretic hormone secretion (SIADH) on Day 3 post-operatively. To our knowledge, this is the first documented case of SIADH arising after an endoscopic intervention for frontal sinusitis.
The history and development of public health in low- and middle-income countries
Authors: Sein Than
Published: December 2021

The history and development of public health in low- and middle-income countries (LMICs) shows that important breakthroughs in public health interventions have led to great improvements in economic development. Health determines economic productivity and prosperity, and the physical and emotional well- being of the people. The mindset of the population afflicted with a high infant mortality rate usually lacks the secure knowledge of its children’s longevity, witnesses higher fertility rates, and experiences the quality- quantity trade- off in child- rearing. Ever since the health- for- all movement was initiated over three decades ago, health, equity, and social justice remain the main themes of social and health policy. It is essential for all public health professionals to sustain these values, especially those in LMICs and the international community.
Public health priorities in countries undergoing economic transition
Authors: Tollman Stephen , Price Jessica
Published: December 2021

This chapter starts by reviewing the relationship between the economy and health, looking at changes in health outcome as income increases, demographic transitions related to economic growth, and the impact of urbanization on health outcomes. It then reviews major health challenges facing middle-income countries (MICs), including the triple burden of disease, multimorbidity, mental health across the life course, and the impacts of migration, climate change, and antimicrobial resistance. Finally, it discusses health system challenges and the importance of building resilient and ‘learning’ health systems with the agility to adapt to meet MICs’ evolving health needs. We discuss strategies to achieve universal health coverage in MICs and the importance of intersectoral collaboration in promoting health.
Poverty, justice, and health
Authors: Labonté Ronald , Baum Fran , Sanders David
Published: December 2021

Poverty has long been a concern in public health with people living in poor circumstances generally suffering higher burdens of disease. Understanding the persistence of poverty, and of its impacts on health, unavoidably intersects with analyses of how inequalities arise in the distribution of income and wealth, and of the material and psychosocial resources these socioeconomic privileges accord. This chapter reviews different definitions of poverty, trends in the distribution of absolute and relative poverty, and strengths and weaknesses of the different concepts. It touches briefly on how poverty (by whatever definition) influences health, citing natural/social selection, cultural/behavioural, and materialist/structural explanations; and discusses how, in some instances, there is reverse causality with poor health worsening individual or household poverty, particularly in low-income countries suffering high disease burdens and weak health systems. The chapter then turns to a review of major theories of justice and how these argue for interventions, and the role that international human rights might play in furthering actions to reduce poverty-related health inequalities. It concludes with a short discussion of different sociopolitical approaches to poverty reduction, providing three examples of intervention policies.
Climate change and human health
Authors: Woodward Alistair , Macmillan Alex
Published: December 2021

Climate change belongs in a new category of global environmental health problems. It is not just that the impacts are widely distributed: climate change is a result of unbalanced global systems. It is one of the modern threats to a ‘safe operating space’ for the planet. The effects on health occur directly, such as increased heat waves; through pressures on natural systems (reduced crop yields and undernutrition, for instance); and, as a consequence of social disruption. Also there may be impacts due to policy responses to climate change: these are so-called ‘transition risks’. Improving baseline health status is fundamental to coping with climate change, because the populations that are most seriously affected are those that already bear a heavy burden of disease. But an undifferentiated public health response is not sufficient. There are distinctive features of climate change that have to be taken into account. Mitigation, or primary prevention, will require rapid, deep cuts in greenhouse emissions if global heating is to be limited. The goal is to identify common solutions, responses to climate change that are health-enhancing rather than health damaging. There are many candidates, but by and large they are not on the path of ‘business as usual’ development.
Behavioural determinants of health and disease
Authors: Green Lawrence W. , Hoeft Kristin S. , Hiatt Robert A.
Published: December 2021

This chapter reviews ways in which behaviour relates to the spectrum of health and disease determinants, from environmental to genetic, in shaping health outcomes. It builds on the previous chapters in recognizing the powerful influence of socioeconomic and cultural factors, especially poverty and discrimination, in influencing both behaviour and health. Many commentaries in the past four decades have attempted to correct the overemphasis on individual behavioural determinants of health by discounting and sometimes disparaging any focus on individual behaviour or personal responsibility in disease prevention and health promotion. This chapter seeks a middle ground, building on the growing understanding of the ecological and cultural context of the behaviour–health relationship. It seeks to integrate that knowledge in an approach to public health that acknowledges the reciprocal determinism of behavioural, environmental, and biological determinants rather than minimizing the importance of behaviour in these complex interactions.
Information systems in support of public health in high-income countries
Authors: Staa Tjeerd-Pieter van , Smeeth Liam
Published: December 2021

Public health activities are dependent on the availability of information and ability to disseminate information to clinicians/healthcare providers, individuals, and communities. The increasing computerization of healthcare systems can offer opportunities to improve these activities. Databases of electronic healthcare records are used for disease surveillance and monitoring healthcare interventions. The quality and quantity of reporting of notifiable diseases may be improved by regular review of the electronic healthcare records. Randomized trials that recruit patients at the point of care and use electronic healthcare records for collection of follow-up information can be used to test the effectiveness of healthcare intervention in routine clinical practice. Cluster trials that randomize different clinics or regions can compare different public health policies and improve the evidence base for the pragmatic use of public health interventions. Data generated within clinical information systems can be used to provide feedback and guidance to clinicians and patients as part of clinical care. Better information systems providing data on risks and benefits of healthcare interventions will provide an important impetus to evidence-based public health.
Community diagnosis and health information systems in low- and middle-income countries
Authors: Wu Zunyou , McGoogan Jennifer
Published: December 2021

The inalienable human right to the ‘highest attainable standard of health’ has been a focus of the international public health community for more than 50 years. Yet, low- and middle-income countries (LMIC) still struggle with heavy burden of disease, inefficient health systems, and limited resources for improving the health of their citizens. Community diagnosis can inform public health planning and prioritization of resources for the purpose of addressing disparities in health outcomes. However, large amounts of good-quality data from multiple quantitative and qualitative, primary and secondary sources are ideally required in order to effectively assess current state and evaluate future performance against a broad range of important health metrics. Furthermore, information systems and health metrics should not be thought of as static and separate. Rather, they should ideally evolve together in a deliberate, iterative process over time from metrics selected based upon the information that is available (i.e. measure what is measurable) to information systems designed based upon the metrics that are important to measure (i.e. measure what should be measured). This chapter describes community diagnosis, information systems, and health metrics in the context of LMIC, highlighting these concepts and their challenges with examples of studies conducted in these settings.
New communication technologies, social media, and public health
Authors: Sullivan Patrick S. , Siegler Aaron J. , Hightow-Weidman Lisa
Published: December 2021

New communications technologies constitute a rapidly changing field with tremendous opportunities for public health practice. Platforms include a variety of apps, which share the general characteristics of platforms to share words, text, and video content, but which have important differences in their preferred formats of media, strategies for sharing information within social networks, and user bases. These technologies can facilitate public health efforts through the provision of information, as portals for communication with those in need of services, and as platforms for public health interventions. Social media platforms also give rise to the possibility of using public data to increase understanding of health concerns and programmes—for example, using public data on internet searches or social media postings to identifying trends in infectious diseases. Despite these exciting possibilities, there are important heterogeneities globally in the coverage of smartphone devices, in data speed, and in access to data services. There are also important considerations about possible harms of technologies, and about privacy concerns for users of social media in the context of public health.
Epidemiology
Authors: Detels Roger
Published: December 2021

Epidemiology is the basic science of public health, because it is the science that describes the relationship of health and/or disease with other health-related factors in human populations, such as human pathogens. Furthermore, epidemiology has been used to generate much of the information required by public health professionals to develop, implement, and evaluate effective intervention programmes for the prevention of disease and promotion of health. Unlike pathology, which constitutes a basic area of knowledge, and cardiology, which is the study of a specific organ, epidemiology is a philosophy and methodology that can be applied to learning about and resolving a very broad range of health problems. It is not enough to know what the various study designs and statistical methodologies are. The ‘art’ of epidemiology is knowing when and how to apply the various epidemiological strategies creatively to answer specific health questions. The uses and limitations of the various epidemiological study designs are presented in this chapter to illustrate and underscore the fact that the successful application of epidemiology requires more than knowledge of study designs and epidemiological methods. This introductory chapter attempts to define epidemiology, to present ways in which epidemiology is used in the advancement of public health, and finally, to discuss the range of applications of epidemiological methodologies.
Principles of outbreak investigation
Authors: Iamsirithaworn Sopon , Thammawijaya Panithee , Ungchusak Kumnuan
Published: December 2021

Outbreak investigation is an essential function of public health professionals. It is an opportunity to gain new knowledge of diseases and to discover the weaknesses of current public health practices and systems. Unfortunately, most outbreaks are not investigated. This chapter will present the principles and important points about outbreak investigation. The reader will learn about how to detect outbreaks from routine official surveillance and unofficial sources. The reader can assume oneself as an investigator who has to organize the team, review previous knowledge, and prepare the technical and management aspects, before starting the investigation. The reader will learn about the major ten steps in the investigation, with examples, which starts by confirming the existence of the outbreak, verifying the diagnosis, gathering case information, descriptive epidemiology, formulating and testing the hypothesis when necessary, conducting environmental surveys to supplement epidemiological evidence, providing timely on-site reporting of the findings, with practical recommendations to local and national responsible authorities, and communicating risk to health professional community and public. The reader is reminded about the need to follow-up on the recommendations and continue vigorous surveillance of the health problem. The chapter ends by forecasting more joint international investigations to control emerging diseases and new problems. After reading this chapter, the reader should be clear that outbreak investigation is an interesting, challenging, and important task requiring a competent investigator who combines sound scientific knowledge and good management.
Case–control studies
Authors: Weiss Noel S.
Published: December 2021

Case–control studies compare ill or injured individuals (cases) with those at risk of the illness or injury (controls) with regard to prior exposures or characteristics, and so appear to proceed backwards, from consequence to potential cause. They have the potential to identify associations that are not causal, either because of chance, or because of the influence of some other factor associated with both the exposure and outcome. However, if a case–control study is able to enrol cases and controls from the same underlying population at risk of the outcome, and can measure exposure status of these persons in a valid manner, the results obtained will closely resemble those of a properly performed cohort study.
Cohort studies
Authors: Muñoz Alvaro , Nieto F. Javier
Published: December 2021

The simplest cohort design is to obtain exposure data at baseline and follow-up individuals to obtain data up to the point when the event of interest occurs. A richer design includes regularly scheduled visits at which data on exposures are updated. The exposures can be either fixed over time (e.g. race), change directly with time (e.g. age and calendar), or change at their own pace (e.g. biological markers). According to the scientific aims of a cohort study, disease occurrence can be measured as an event in person-time, time-to-endpoint of interest, or change in a biomarker repeatedly measured at follow-up visits. Analytical methods include survival analyses to handle censored observations and late entries due to incomplete observation of the development of events and origin, and longitudinal data analyses for the trajectories of markers of disease progression. Stratification, multivariate regression, and causal inference methods are key tools to accomplish comparability among exposed and unexposed groups. Identification of exposures and risk factors for disease provides a basis for prevention strategies. Data from cohort studies can be used to assess the effects of interventions by using data at the individual level to determine individual effectiveness or by comparing occurrence of disease in the population when typically none or only a few are intervened to determine population effectiveness.
Community intervention trials in high-income countries
Authors: Farquhar John W. , Green Lawrence W.
Published: December 2021

Community intervention trials in high-income countries. This chapter summarizes results of combined mass media and community organizing methods used and evaluated during the past 40 years to achieve chronic disease prevention through changes in behaviour and risk factors. These studies are examples of experimental epidemiology and community-based participatory research, using cost-effective health promotion methods. The chapter also reviews earlier experiences in public screening, immunization, family planning, HIV/AIDS, and tobacco control, which provided useful theory and methods on which the later trials built. Major advances in theory development and intervention methods occurred in the 1970s from two pioneering community intervention projects on cardiovascular disease prevention from Stanford (USA) and Finland. These projects, followed in the 1980s and beyond in North America, Europe, Australia, and elsewhere, added many major lessons in both theory and practice. These lessons, considered ‘operational imperatives’, are: economic, social normative (or ‘denormalization’), informed electorate, public health, surveillance, comprehensiveness, formative, ecological, and logical sequencing of needs and action. Therefore, these recent decades of applying ‘total community’ health promotion in developed countries achieved considerable change at reasonable cost. Such communities were changed greatly through organizing and education; changes requiring advocacy, activism, partnership building, leadership, and regulations. This results in community transformation, creating ‘community efficacy’, a composite of enhanced self-efficacy of the community’s residents and leaders. Such transformed communities, as models, allow leverage in disseminating methods, including regulatory tactics. Such dissemination can lead to national changes analogous to those of the recent decade’s tobacco control successes.
Causation and causal inference
Authors: Hoggatt Katherine J. , VanderWeele Tyler J. , Greenland Sander
Published: December 2021

This chapter provides an introduction to causal inference theory for public health research. Causal inference can be viewed as a prediction problem, addressing the question of what the likely outcome will be under one action vs. an alternative action. To answer this question usefully requires clarity and precision in both the statement of the causal hypothesis and the techniques used to attempt an answer. This chapter reviews considerations that have been invoked in discussions of causality based on epidemiologic evidence. It then describes the potential-outcome (counterfactual) framework for cause and effect, which shows how measures of effect and association can be distinguished. The potential-outcome framework illustrates problems inherent in attempts to quantify the changes in health expected under different actions or interventions. The chapter concludes with a discussion of how research findings may be translated into policy.
Systematic reviews and meta-analysis
Authors: Siegfried Nandi , Mbuagbaw Lawrence
Published: December 2021

Systematic reviews play an important role in healthcare decision-making. When conducted correctly, they provide up-to-date, comprehensive, and replicable summaries of evidence. Authors of systematic reviews are expected to develop a protocol that outlines the research question and key methodological features of their review. A comprehensive and exhaustive search should be conducted, followed by screening to capture studies that meet the prespecified inclusion criteria. Once the relevant studies have been identified, data will be extracted, using a dedicated tool that permits the review authors to confirm the eligibility of the study and collect information on its design, risk of bias, and results. Sufficiently similar data may be pooled using meta-analytic techniques or synthesized narratively. A summary of the overall quality of evidence for each outcome is an essential component of a systematic review. The main concerns with systematic reviews are (1) selection bias: systematic exclusion of relevant studies due to publication status or language; (2) indexing bias: failure to identify relevant studies because they are not indexed accurately; and (3) information bias: missing or inaccurate information in the included studies. Other approaches to evidence synthesis include mapping the evidence with scoping reviews; conducting overviews of systematic reviews; using individual patient data; conducting network meta-analyses for multiple comparisons; conducting rapid reviews when evidence is needed urgently; synthesis of diagnostic accuracy data; and synthesis of qualitative data. Systematic reviews often inform clinical guidelines and require careful planning and execution by teams with content and methodological expertise.
Measuring the health of populations
Authors: Vos Theo , Murray Christopher J.L. , Lopez Alan D.
Published: December 2021

Over the last two decades, the global health landscape has undergone rapid transformation. People around the world are living longer than ever before, and populations are getting older. Many countries have made remarkable progress in preventing child deaths. As a result, disease burden is increasingly defined by disability as opposed to being dominated by premature mortality. The leading causes of death and disability are shifting from communicable diseases in children to non-communicable diseases in adults. These global trends differ across regions and by level of development. Notably, in sub-Saharan Africa, communicable, maternal, and newborn diseases and nutritional deficiencies continue to dominate. While low- and middle-income countries are tackling this ‘unfinished agenda’ of largely poverty-related diseases, increasingly they also need to prepare their health services for a growing burden of non-communicable diseases and injuries. In high-income countries, health budgets are steadily increasing relative to gross domestic product due to ageing of the population, an ever-expanding array of medical technologies, and greater demands of consumers for healthcare services. For governments and other healthcare providers to be able to respond to these challenges, high-quality comparable data on the size and trends in mortality and morbidity are essential. In 2007, the Bill & Melinda Gates Foundation funded the Global Burden of Diseases, Injuries, and Risk Factors Study 2010, which endeavoured to rethink methods and assumptions underlying population health measurement while making use of the vastly improved health data and computational resources. This chapter describes the methods underlying the Global Burden of Disease (GBD) study.
Mathematical models of transmission and control of infectious agents
Authors: Welte Alex , Schalkwyk Cari van
Published: December 2021

Indeed, the ‘heavy lifting’ of healthcare is in the care of patients, the development and distribution of vaccines, drugs and devices, and the conception and implementation of sensible systems and policies. However, in recent decades, spectacular increases in the availability of computational capacity have paved the way for mathematical modelling to play an ever-increasing role in many aspects of public health, by supporting formal analyses at various scales of the processes involved. This chapter explores a particular kind of ‘modelling’—and it is not the common (bio)statistical kind. We focus on what we would call ‘dynamical’ modelling (as opposed to ‘statistical’ modelling). This essentially entails the reduction, to mathematics, of key facts and principles inherent in the ‘processes’ or ‘mechanisms’ in an epidemiological situation. We can then manipulate these mathematical constructs, in search of insights that, while ultimately implied in the model construction, are not superficially apparent from our primary data and our intuition.
Life course epidemiology and analysis
Authors: Rose Mayeda Elizabeth , Binder Alexandra M. , Kobayashi Lindsay C.
Published: December 2021

Life course epidemiology approaches disease aetiology and prevention from the perspective of risk and protective factors that influence health and disease throughout the lifespan. The integration of a life course approach to epidemiologic research is central for identifying effective policies and programmes to promote population health and health equity. This chapter will introduce life course concepts and models and analytical approaches for research on life course determinants of health. It will discuss threats to causal inference, approaches for overcoming these difficulties, and future directions in life course epidemiology. For example, in addition to expanding epidemiologic research with a life course perspective to include people with diverse life experiences, new areas of development include life course research extending beyond one human lifespan to include intergenerational and transgenerational life course research, as well as the application of innovative methods.
Demography and public health
Authors: Grundy Emily , Murphy Michael
Published: December 2021

The health and healthcare needs of a population cannot be measured or met without knowledge of its size and characteristics. Demography is the scientific study of population and is concerned both with the measurement, or estimation, of population size and structure and with population dynamics—the interplay between fertility, mortality, and migration which determines population change. These are pre-requisites for making the forecasts about future population size and structure which largely determine the health profile of a population and should underpin public health planning. This chapter presents information on demographic methods and data sources, their application to health and population issues, information on demographic trends and their implications, and the major theories about demographic change. The aim is to illustrate and elucidate the complex inter-relationship between population change and human health.
Health promotion, health education, and the public’s health
Authors: Baum Fran
Published: December 2021

Health promotion is a complex, ambiguous concept and set of practices. While many have linked it, primarily, to a revolution in health education, its roots go much deeper into the history of public health. It had its contemporary beginnings in the throes of the backlash against bureaucratic and professional dominance exemplified by the new social movements of the 1970s and 1980s. At its heart, health promotion is centred on the values and principles of equity, participation, and empowerment. These concepts are embedded in health promotion’s founding document, the Ottawa Charter for Health Promotion. However, exactly how these values are articulated is often ambiguous. In this chapter, the authors contend that health promoters must intensify their reflection on these core values and principles; particularly in the light of the tendency to slip back into a comfortable paternalism, which reinforces existing power imbalances. We are specifically concerned with the precise interpretation of health equity in health promotion.
Toxicology and environmental risk analysis
Authors: Koh David , Lin Ro-Ting
Published: December 2021

Risk-based decision-making increasingly has global dimensions, extending from the international management of chemical risks to the sustainable development of our planet. Environmental risk analysis is firmly based on toxicological sciences with input from other public health disciplines. Increasing understanding of how the human genotype and phenotype affects absorption, distribution, metabolism, and excretion of xenobiotics (compounds foreign to a living organism), is providing insight into answers to the oldest human question about disease: ‘Why me?’ The risk paradigm components of hazard assessment, dose–analysis, exposure assessment, risk characterization, risk management, and risk communication, and the toxicological concepts on which they are based, have proven durable in approaching increasingly complex environmental hazards. Newer approaches to managing risk, such as the precautionary principle, and newer challenges, such as nanotechnology and genetically modified organisms, necessitate further systematic thinking on how best to protect human health and the environment.
Physical activity and public health
Authors: Hadgraft Nyssa T. , Owen Neville , Dempsey Paddy C.
Published: December 2021

There are well-established chronic disease prevention and broader public health benefits associated with being physically active. However, large proportions of the adult populations of developed countries and rapidly urbanizing developing countries are inactive. Additionally, many people’s lives are now characterized by large amounts of time spent sitting—at work, at home, and in automobiles. Widespread urbanization, particularly in low- and middle-income countries, has resulted in large segments of traditionally active rural populations moving into cities. Many previously manual tasks in the occupational and household sectors have become automated, making life easier and safer in many respects. However, a pervasive consequence of these developments is that large numbers of people globally are now going about their daily lives in environments that place them at risk of overweight and obesity, type 2 diabetes, cardiovascular disease, and other health problems. This represents a formidable set of public health challenges. In this context, the present chapter describes: key definitions and distinctions relating to physical activity, exercise, and sedentary behaviour; current evidence on relationships physical inactivity and sitting time with health outcomes, and associated public health recommendations; prevalence and trends in physical activity and sedentary behaviours, and some of the key issues for surveillance and measurement; and, how physical activity and sedentary behaviour may be understood in ways that will inform broad-based public health approaches. An interdisciplinary and intersectoral strategy is emphasized. This requires working with constituencies beyond the public health field, such as urban planning, architecture, occupational health and safety, and social policy.
Public mental health and suicide
Authors: Wasserman Danuta , Wahlbeck Kristian
Published: December 2021

The full public health impact of mental health is largely unrecognized. The allocation of the burden of disease attributable to mental and behavioural disorders, which is already substantial, will probably increase steadily in the future, due to the transition of the global disease burden towards mental and behavioural disorders. In addition to the demands that mental disorders put on social welfare and health systems, they also cause decreased productivity in the workplace, prolonged disability, and diminished resources within families. Mental disorders are linked to socioeconomic disadvantages and addressing mental health determinants will reduce health inequalities. Stigma of mental disorders is widespread, and it is a barrier for help-seeking behaviours, as well as the development of healthcare services. Modern mental health policies should aim at improving psychosocial health by addressing determinants of mental health in all public policies. Key measures in effective public health suicide prevention programmes comprise improved awareness in the population about mental health promotion and suicide preventive measures, the restriction of access to lethal means of suicide, responsible media coverage of suicide issues, school-based awareness programmes, and improvements in the identification of depression and suicidality by peers, gatekeepers, and health professionals. Modern community-based mental health services, with a diversified service provision, result in better outcomes on a broader scale compared to ‘old school’ hospital-centred mental health service systems. Primary care physicians in collaboration with multidisciplinary teams have a central role in provision of mental health services to the population.