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Mercury emissions to the atmosphere and its transport, transformation and deposition to and re-emission from terrestrial and aquatic ecosystems on hemispherical and global scales has received increasing attention from both the scientific and the regulatory communities during the last twenty years. It is well known that the atmosphere is the major transport media through which mercury is redistributed on global scale once it is released from point and diffuse emission sources. A substantial amount of research has been carried out worldwide aiming to assess the relationships between emissions from natural vs. anthropogenic sources, inter-hemispherical atmospheric transport patterns, and atmospheric deposition to and re-emission from oceans, its bioaccumulation in fish, and evaluation of policy strategies to reduce the impact of mercury emissions on human health and ecosystems. This chapter provides a highlight of key aspects related to mercury contamination, including: a) major processes affecting the mercury cycle between the atmosphere and aquatic and terrestrial ecosystems, b) mercury emissions from natural and anthropogenic sources, c) spatial and temporal distributions and trends of mercury species over the northern and southern hemispheres, d) the chemical and physical processes affecting the transport and fate of atmospheric mercury, and e)major policy frameworks aiming to control the impact of mercury on human health and ecosystems.

The interactions most supportive of positive child development take place in moments of close contact with others. In the earliest years of life, a child's caregivers are the primary partners in these important interactions. Little is known about the patterns of real-life physical interactions between children and their caregivers, in part due to an inability to measure these interactions as they occur in real time. We have developed a wearable, infrastructure-free device (TotTag) used to dynamically and unobtrusively measure physical proximity between children and caregivers in real time. We present a case-study illustration of the TotTag with data collected over two (12-hour) days each from two families: a family of four (30-month-old son, 61-month-old daughter, 37-year-old father, 37-year-old mother), and a family of three (12-month-old daughter, 35-year-old-father, 33-year-old mother). We explored patterns of proximity within each parent-child dyad and whether close proximity would indicate periods in which increased opportunity for developmentally critical interactions occur. Each child also wore a widely used wearable audio recording device (LENA) to collect time-synced linguistic input. Descriptive analyses reveal wide variability in caregiver-child proximity both within and across dyads, and that the amount of time spent in close proximity with a caregiver is associated with the number of adult words and conversational turns to which a child was exposed. This suggests that variations in proximity are linked to-though, critically, not synonymous with-the quantity of a child's exposure to adult language. Potential implications for deepening the understanding of early caregiver-child interactions are discussed.

A number of contemporary chemical transport models for mercury are applied within the framework of the EU GMOS project to study principal processes of mercury transport and transformations in the atmosphere. Each model is involved in simulation of short-term episodes corresponding to particular Hg measurement campaigns in Europe and other regions. In order to evaluate different physical and chemical mechanisms the models perform sensitivity runs with various parameterizations and/or combinations of considered processes. The modeling results are compared to detailed measurements of Hg species (Hg0/TGM, RGM, HgP) with high temporal resolution (hours) aiming at reproduction of short-term temporal variability of Hg air concentration.

The modelling of atmospheric Hg chemistry, transport and deposition has progressed significantly over the last few years, aided by a number of factors. These include an improved understanding of the processes involved in the atmospheric Hg cycle, advances in computer performance, an ever increasing archive of measurement data with which model results may be compared, and also an increase in the number of models (global, regional and zero-dimensional) currently in use. The increase in the number of models has permitted model intercomparisons to be performed for the first time. The number of global models available to provide initial and boundary conditions for regional models has increased and the possibility of using modelling ensembles to verify emission and deposition fluxes is close to becoming a reality. This abstract describes the development of a mercury chemistry version of the WRF/Chem, which due to the architecture of the model permits a number of chemical mechanisms to be employed within the same model.

Only a few years ago the presence of Reactive Gaseous Mercury (RGM) was believed to be almost exclusively the result of anthropogenic emissions and that sustained high RGM concentrations in the MBL were not considered likely. During the past ten years, an in-depth investigation was carried out in the Marine Boundary Layer (MBL) of the Mediterranean Sea to quantify and possibly explain spatial and temporal patterns of Hg-species concentrations. This paper provides an overview of modeling results and atmospheric measurements performed during several cruise campaigns performed aboard the Research Vessel (RV) URANIA of the CNR over the Mediterranean sea basin. RGM concentrations have been modelled using a photochemical box model of the MBL and compared to measured data obtained during the research cruises. The comparison results supports the hypothesis that there are daytime mercury oxidation reactions occurring which have not yet been identified. Major findings of key studies carried out during ten years of ship-borne activities have been highlighted.

The interactions most supportive of positive child development take place in moments of close contact with others. In the earliest years of life, a child's caregivers are the primary partners in these important interactions. Little is known about the patterns of real-life physical interactions between children and their caregivers, in part due to an inability to measure these interactions as they occur in real time. We have developed a wearable, infrastructure-free device (TotTag) used to dynamically and unobtrusively measure physical proximity between children and caregivers in real time. We present a case-study illustration of the TotTag with data collected over two (12-hour) days each from two families: a family of four (30-month-old son, 61-month-old daughter, 37-year-old father, 37-year-old mother), and a family of three (12-month-old daughter, 35-year-old-father, 33-year-old mother). We explored patterns of proximity within each parent-child dyad and whether close proximity would indicate periods in which increased opportunity for developmentally critical interactions occur. Each child also wore a widely used wearable audio recording device (LENA) to collect time-synced linguistic input. Descriptive analyses reveal wide variability in caregiver-child proximity both within and across dyads, and that the amount of time spent in close proximity with a caregiver is associated with the number of adult words and conversational turns to which a child was exposed. This suggests that variations in proximity are linked to-though, critically, not synonymous with-the quantity of a child's exposure to adult language. Potential implications for deepening the understanding of early caregiver-child interactions are discussed.

The sexes of sequentially hermaphroditic cupped oysters are both environmentally and genetically determined. Sex is also associated with growth or body size, females being larger than males of the same age on average. Whether sex determines size or size determines sex has not been resolved. To examine the relationship between growth and sex, 1,360 tagged individuals from six F, families of Pacific oyster Crassostrea gigas were reared through their second summer in Thorndyke Bay, Washington; individual live weights were recorded for 5 consecutive months, starting in June. At the last weighing, microscopic examination of gonadal tissue revealed four 'sexes' in the cohort, females (43% of cohort), males (29%), hermaphrodites (2%), and sex-undetermined individuals with no gametes (26%). Live weights were fit to various sigmoidal growth curves (logistic, Gompertz, and Richards) with fixed and random parameters to account for individual variation. The best fitting curves suggested that growth of the cohort was exponential until late August, when temperatures declined and more than 70% of final weight had been gained. Individual live weights, growth-curve parameters, and growth measures were fit to general linear models with family and sex classification variables. Family-by-sex interaction was significant in many such analyses. Females were larger than males on average and appeared to attain their size advantage from superior growth characteristics rather than from initial size. Males were strikingly either like females or like the smaller sex-undetermined oysters with respect to growth comparisons within family. Sex-undetermined oysters may have been 'true' males that were too small to mature as yearlings, though a size-threshold for maturation was not apparent. Genetically determined sex and family genetics appeared to control growth. KEY WORDS: Richards growth curves, repeated measures, seasonal growth, tagged oysters, [F.sub.2] families, Crassostrea gigas, INTRODUCTION Both genetic and environmental factors determine sex of the Pacific oyster Crassostrea gigas (Guo et al. 1998, Hedrick & Hedgecock 2010), which, like other cupped oysters of the genus [...]

I'm just questioning my existence a lot, questioning my purpose. It doesn't feel real to me. Nothing has felt real to me in a long time.... I don't know what [...]

Abstract Background Prior literature has shown that physicians with healthy personal habits are more likely to encourage patients to adopt similar habits. However, despite the possibility that promoting medical student health might therefore efficiently improve patient outcomes, no one has studied whether such promotion happens in medical school. We therefore wished to describe both typical and outstanding personal health promotion environments experienced by students in U.S. medical schools. Methods We collected information through four different modalities: a literature review, written surveys of medical school deans and students, student and dean focus groups, and site visits at and interviews with medical schools with reportedly outstanding student health promotion programs. Results We found strong correlations between deans' and students' perceptions of their schools' health promotion environments, including consistent support of the idea of schools' encouraging healthy student behaviors, with less consistent follow-through by schools on this concept. Though students seemed to have thought little about the relationships between their own personal and clinical health promotion practices, deans felt strongly that faculty members should model healthy behaviors. Conclusions Deans' support of the relationship between physicians' personal and clinical health practices, and concern about their institutions' acting on this relationship augurs well for the role of student health promotion in the future of medical education. Deans seem to understand their students' health environment, and believe it could and should be improved; if this is acted on, it could create important positive changes in medical education and in disease prevention.

Abstract. Polycyclic aromatic hydrocarbons (PAHs) are hazardous pollutants, with increasing emissions in pace with economic development in East Asia, but their distribution and fate in the atmosphere are not yet well understood. We extended the regional atmospheric chemistry model WRF-Chem (Weather Research Forecast model with Chemistry module) to comprehensively study the atmospheric distribution and the fate of low-concentration, slowly degrading semivolatile compounds. The WRF-Chem-PAH model reflects the state-of-the-art understanding of current PAHs studies with several new or updated features. It was applied for PAHs covering a wide range of volatility and hydrophobicity, i.e. phenanthrene, chrysene and benzo[a]pyrene, in East Asia. Temporally highly resolved PAH concentrations and particulate mass fractions were evaluated against observations. The WRF-Chem-PAH model is able to reasonably well simulate the concentration levels and particulate mass fractions of PAHs near the sources and at a remote outflow region of East Asia, in high spatial and temporal resolutions. Sensitivity study shows that the heterogeneous reaction with ozone and the homogeneous reaction with the nitrate radical significantly influence the fate and distributions of PAHs. The methods to implement new species and to correct the transport problems can be applied to other newly implemented species in WRF-Chem.

This essay provides an overview of three avenues by which emerging technology affects the international order: perceptions of technological effects, alliance integration and operability, and compliance with liberal ordering principles. It concludes with three recommendations for policymakers. First, strategically implement the 'hype' surrounding emerging technologies. Second, when integrating technology into alliance doctrine, carefully address abandonment and entrapment concerns to ensure ally buy-in. Finally, understand that technological advances have changed the set of options available to policymakers below the level of armed conflict, thereby reverberating on perceptions of the liberal order and opening alternative routes to state alignment. [ABSTRACT FROM AUTHOR]

The Multi-Compartment Hg (mercury) Modeling and Analysis Project (MCHgMAP) is an international multi-model research initiative intended to simulate and analyze the geospatial distributions and temporal trends of environmental Hg to inform the effectiveness evaluations of two multilateral environmental agreements (MEAs): the Minamata Convention on Mercury (MC) and Convention on Long-Range Transboundary Air Pollution (LRTAP). This MCHgMAP overview paper presents its science objectives, background and rationale, experimental design (multi-model ensemble (MME) architecture, inputs and evaluation data, simulations and reporting framework), and methodologies for the evaluation and analysis of simulated environmental Hg levels. The primary goals of the project are to facilitate detection and attribution of recent (observed) and future (projected) spatial patterns and temporal trends of global environmental Hg levels, and identification of key knowledge gaps in Hg science and modeling to improve future effectiveness evaluation cycles of the MEAs. The current advances and challenges of Hg models, emission inventories, and observational data are examined, and an optimized multi-model experimental design is introduced for addressing the key policy questions of the MEAs. A common set of emissions, environmental conditions, and observation datasets are proposed (where possible) to enhance the MME comparability. A novel harmonized simulation approach between atmospheric, land, oceanic and multi-media models is developed to account for the short- and long-term changes in secondary Hg exchanges and to achieve mechanistic consistency of Hg levels across environmental matrices. A comprehensive set of model experiments is developed and prioritized to ensure a systematic analysis and participation of a variety of models from the scientific community. [ABSTRACT FROM AUTHOR]

A mercury (Hg) tracer model based on WRF-Chem has been developed to provide a rapid and relatively simple tool to evaluate the local and regional impact of Artisanal and Small Scale Gold Mining activities which use Hg amalgamation.Artisanal gold mining, its use of mercury amalgamation and its potential for human and environmental harm is mentioned specifically in the Foreword by the Secretary-General of the United Nations António Guterres of the Minamata Convention on Mercury: Text and Annexes (2023 edition, url below). Much of this artisanal mining occurs in the Tropics, and often in densely forested regions and the role of vegetation in the global atmospheric mercury cycle has been shown to be significant in recent years. The model employs a simple lifetime approach to Hg0 oxidation based on KPP and an ad hoc deposition scheme which calculates the foliar uptake of Hg0( g) based on the Leaf Area Index, dry deposition of HgII(g) , and the wet deposition of HgII(g) by convective and non-convective precipitation. A number of demonstration simulations are presented using four example domains from South-East Asia and South America, and five from Africa. The results highlight the diversity of the local impacts of ASGM due to land category, geography and meteorology, but also point to the fact that just as there are always local impacts there are also repercussions for the global atmospheric mercury burden (https://minamataconvention.org/sites/default/files/documents/information_document/Minamata-Convention-booklet-Oct2023-EN.pdf). [ABSTRACT FROM AUTHOR]

Technology is often an importance consideration in a state's theory of victory. States must consider how technology advances their strategic ends and the most appropriate ways to source technology. As states seek technological overmatch or offsets, they must also wrestle with the strategic cost, risk, and advantage of emerging technologies. Yet, technological advantage is likely to be fleeting. Successful competition depends on states' ability to scale rapidly in times of crisis, to train soldiers in network-centric and austere environments, to effectively establish norms of AI use, to compete in the diffusion of global dual-use technology, and to question assumptions of technological emergence. [ABSTRACT FROM AUTHOR]