Great Societal Concern Research Articles

Weakening of springtime Arctic ozone depletion with climate change

Abstract. In the Arctic stratosphere, the combination of chemical ozone depletion by halogenated ozone-depleting substances (hODSs) and dynamic fluctuations can lead to severe ozone minima. These Arctic ozone minima are of great societal concern due to their health and climate impacts. Owing to the success of the Montreal Protocol, hODSs in the stratosphere are gradually declining, resulting in a recovery of the ozone layer. On the other hand, continued greenhouse gas (GHG) emissions cool the stratosphere, possibly enhancing the formation of polar stratospheric clouds (PSCs) and, thus, enabling more efficient chemical ozone destruction. Other processes, such as the acceleration of the Brewer–Dobson circulation, also affect stratospheric temperatures, further complicating the picture. Therefore, it is currently unclear whether major Arctic ozone minima will still occur at the end of the 21st century despite decreasing hODSs. We have examined this question for different emission pathways using simulations conducted within the Chemistry-Climate Model Initiative (CCMI-1 and CCMI-2022) and found large differences in the models' ability to simulate the magnitude of ozone minima in the present-day climate. Models with a generally too-cold polar stratosphere (cold bias) produce pronounced ozone minima under present-day climate conditions because they simulate more PSCs and, thus, high concentrations of active chlorine species (ClOx). These models predict the largest decrease in ozone minima in the future. Conversely, models with a warm polar stratosphere (warm bias) have the smallest sensitivity of ozone minima to future changes in hODS and GHG concentrations. As a result, the scatter among models in terms of the magnitude of Arctic spring ozone minima will decrease in the future. Overall, these results suggest that Arctic ozone minima will become weaker over the next decades, largely due to the decline in hODS abundances. We note that none of the models analysed here project a notable increase of ozone minima in the future. Stratospheric cooling caused by increasing GHG concentrations is expected to play a secondary role as its effect in the Arctic stratosphere is weakened by opposing radiative and dynamical mechanisms.

Increased variability of the western Pacific subtropical high under greenhouse warming.

SignificanceThe western Pacific subtropical high (WPSH) channels moisture from the tropics that underpins the East Asian summer climate. Interannual variability of the WPSH dominates climate extremes in the densely populated countries of East Asia. In 2020, an anomalously strong WPSH led to catastrophic floods with hundreds of deaths, 28,000 homes destroyed, and tens of billions in economic damage in China alone. How the frequency of such strong WPSH events will change is of great societal concern. Our finding of an increase in future WPSH variability, translating into an increased frequency of climate extreme as seen in the 2020 episode, highlights the increased risks for the billions of people in the densely populated East Asia with profound socioeconomic consequences.

DEGREES OF LATENCY OF ECOLOGICAL DISCOURSE AGENT (A CASE STUDY OF BRITISH ONLINE NEWSPAPERS)

This article proposes a study of degrees of latency of the agent, which is a semantic role performed by a participant of the communicative situation described in a sentence; this role correlates with the instigator of the action. The agent can be expressed explicitly, so that everybody understands who the action is performed by, or in a hidden, latent way. Drawing on Goatly’s (2018) research which demonstrates that degrees of agent’s latency can vary, we modify his scale of latency by taking into consideration non-verbal (visual) means. A great societal concern for environmental issues around the globe nowadays, together with the ecolinguistic vector of this research account for its timeliness. The purpose of this research is to identify the degrees of latency of the agent of environmental discourse. Syntactic constructions, lexical units, and visual images that render the agent were chosen as the object-matter of analysis, while the degrees of latency – as its subject-matter. The methods comprise general scientific methods, such as induction and deduction, synthesis and analysis, observation and contrast, as well as linguistic methods proper: critical discourse analysis, semantic analysis, and multimodal analysis. The sample is selected from online versions of most widely read British newspapers, both broadsheets and tabloids, The Guardian and Metro respectively. A modified scale of degrees of agent’s latency is suggested, where six categories of linguistic means are differentiated according to the degree of their latency. Explicit predication is characterized by a zero degree of latency; its measure increases in grammatical constructions, tropes, nominalizations, ellipsis, and indefinite agent respectively. The prospects of this research lie in comparison and quantitative counts of the agent’s latency in different types of British media.

Mitochondrially-Targeted Therapeutic Strategies for Alzheimer's Disease.

Alzheimer’s disease (AD) is an irreversible, progressive neurodegenerative disease and the most common cause of dementia among older adults. There are no effective treatments available for the disease, and it is associated with great societal concern because of the substantial costs of providing care to its sufferers, whose numbers will increase as populations age. While multiple causes have been proposed to be significant contributors to the onset of sporadic AD, increased age is a unifying risk factor. In addition to amyloid-β (Aβ) and tau protein playing a key role in the initiation and progression of AD, impaired mitochondrial bioenergetics and dynamics are likely major etiological factors in AD pathogenesis and have many potential origins, including Aβ and tau. Mitochondrial dysfunction is evident in the central nervous system (CNS) and systemically early in the disease process. Addressing these multiple mitochondrial deficiencies is a major challenge of mitochondrial systems biology. We review evidence for mitochondrial impairments ranging from mitochondrial DNA (mtDNA) mutations to epigenetic modification of mtDNA, altered gene expression, impaired mitobiogenesis, oxidative stress, altered protein turnover and changed organelle dynamics (fission and fusion). We also discuss therapeutic approaches, including repurposed drugs, epigenetic modifiers, and lifestyle changes that target each level of deficiency which could potentially alter the course of this progressive, heterogeneous Disease while being cognizant that successful future therapeutics may require a combinatorial approach.

A holistic perspective on soil architecture is needed as a key to soil functions

AbstractSoil functions, including climate regulation and the cycling of water and nutrients, are of central importance for a number of environmental issues of great societal concern. To understand and manage these functions, it is crucial to be able to quantify the structure of soils, now increasingly referred to as their “architecture,” as it constraints the physical, chemical and biological processes in soils. This quantification was traditionally approached from two different angles, one focused on aggregates of the solid phase, and the other on the pore space. The recent development of sophisticated, non‐disturbing imaging techniques has led to significant progress in the description of soil architecture, in terms of both the pore space and the spatial configuration of mineral and organic materials. We now have direct access to virtually all aspects of soil architecture. In the present article, we review how this affects the perception of soil architecture specifically when trying to describe the functions of soils. A key conclusion of our analysis is that soil architecture, in that context, imperatively needs to be explored in its natural state, with as little disturbance as possible. The same requirement applies to the key processes taking place in the hierarchical soil pore network, including those contributing to the emergence of a heterogeneous organo‐mineral soil matrix by various mixing processes, such as bioturbation, diffusion, microbial metabolism and organo‐mineral interactions. Artificially isolated aggregates are fundamentally inappropriate for deriving conclusions about the functioning of an intact soil. To fully account for soil functions, we argue that a holistic approach that centres on the pore space is mandatory while the dismantlement of soils into chunks may still be carried out to study the binding of soil solid components. In the future, significant progress is expected along this holistic direction, as new, advanced technologies become available.HighlightsWe highlight the crucial importance of the temporal dynamics of soil architecture for biological activity and carbon turnover.We reconcile controversial concepts relative to how soil architecture is formed and reshaped with time.Soil is demonstrated to be a heterogeneous porous matrix and not an assembly of aggregates.Biological and physical mixing processes are key for the formation and dynamics of soil architecture.

Global monsoon response to tropical and Arctic stratospheric aerosol injection

Stratospheric aerosol injection (SAI) is considered as a backup approach to mitigate global warming, and understanding its climate impact is of great societal concern. It remains unclear how differently global monsoon (GM) precipitation would change in response to tropical and Arctic SAI. Using the Community Earth System Model, a control experiment and a suite of 140-year experiments with CO2 increasing by 1% per year (1% CO2) are conducted, including ten tropical SAI and ten Arctic SAI experiments with different injecting intensity ranging from 10 to 100 Tg yr−1. For the same amount of injection, a larger reduction in global temperature occurs under tropical SAI compared with Arctic SAI. The simulated result in the last 40 years shows that, for a 10 Tg yr−1 injection, GM precipitation decreases by 1.1% (relative to the 1% CO2 experiment) under Arctic SAI, which is weaker than under tropical SAI (1.9%). Further, tropical SAI suppresses precipitation globally, but Arctic SAI reduces the Northern Hemisphere monsoon (NHM) precipitation by 2.3% and increases the Southern Hemisphere monsoon (SHM) precipitation by 0.7%. Under the effect of tropical SAI, the reduced GM precipitation is mainly due to the thermodynamic term associated with the tropical cooling-induced decreased moisture content. The hemispheric antisymmetric impact of Arctic SAI arises from the dynamic term related to anomalous moisture convergence influenced by the anomalous meridional temperature gradient.

Endocrine-Mediated Mechanisms of Metabolic Disruption and New Approaches to Examine the Public Health Threat.

Obesity and metabolic disorders are of great societal concern and generate substantial human health care costs globally. Interventions have resulted in only minimal impacts on disrupting this worsening health trend, increasing attention on putative environmental contributors. Exposure to numerous environmental contaminants have, over decades, been demonstrated to result in increased metabolic dysfunction and/or weight gain in cell and animal models, and in some cases, even in humans. There are numerous mechanisms through which environmental contaminants may contribute to metabolic dysfunction, though certain mechanisms, such as activation of the peroxisome proliferator activated receptor gamma or the retinoid x receptor, have received considerably more attention than less-studied mechanisms such as antagonism of the thyroid receptor, androgen receptor, or mitochondrial toxicity. As such, research on putative metabolic disruptors is growing rapidly, as is our understanding of molecular mechanisms underlying these effects. Concurrent with these advances, new research has evaluated current models of adipogenesis, and new models have been proposed. Only in the last several years have studies really begun to address complex mixtures of contaminants and how these mixtures may disrupt metabolic health in environmentally relevant exposure scenarios. Several studies have begun to assess environmental mixtures from various environments and study the mechanisms underlying their putative metabolic dysfunction; these studies hold real promise in highlighting crucial mechanisms driving observed organismal effects. In addition, high-throughput toxicity databases (ToxCast, etc.) may provide future benefits in prioritizing chemicals for in vivo testing, particularly once the causative molecular mechanisms promoting dysfunction are better understood and expert critiques are used to hone the databases. In this review, we will review the available literature linking metabolic disruption to endocrine-mediated molecular mechanisms, discuss the novel application of environmental mixtures and implications for in vivo metabolic health, and discuss the putative utility of applying high-throughput toxicity databases to answering complex organismal health outcome questions.

Resource Letter GECC-2: The Greenhouse Effect and Climate Change: The Intensified Greenhouse Effect

Human activities over the past 200 years have increased Earth's greenhouse effect by about 1% relative to the radiative fluxes that drive the climate system. This Resource Letter introduces the physics of this intensified greenhouse effect and of the processes that govern resultant change in climate and provides resources for further study. Context for this examination is provided in a companion Resource Letter (GECC-1) that examined the radiative fluxes that comprise Earth's climate system and the present-day greenhouse effect. The increase in global temperature and other changes in climate resulting from the intensified greenhouse effect are of great societal concern. Developing prognostic capability to determine these responses to the small perturbations that constitute the intensified greenhouse effect to an accuracy that would be useful to inform policymaking is the major challenge facing climate scientists today.

Combination of techniques to quantify the distribution of bacteria in their soil microhabitats at different spatial scales

To address a number of issues of great societal concern at the moment, like the sequestration of carbon, information is direly needed about interactions between soil architecture and microbial dynamics. Unfortunately, soils are extremely complex, heterogeneous systems comprising highly variable and dynamic micro-habitats that have significant impacts on the growth and activity of inhabiting microbiota. Data remain scarce on the influence of soil physical parameters characterizing the pore space on the distribution and diversity of bacteria. In this context, the objective of the research described in this article was to develop a method where X-ray microtomography, to characterize the soil architecture, is combined with fluorescence microscopy to visualize and quantify bacterial distributions in resin-impregnated soil sections. The influence of pore geometry (at a resolution of 13.4 μm) on the distribution of Pseudomonas fluorescens was analysed at macro- (5.2 mm × 5.2 mm), meso- (1 mm × 1 mm) and microscales (0.2 mm × 0.2 mm) based on an experimental setup simulating different soil architectures. The cell density of P. fluorescens was 5.59 x 107(SE 2.6 x 106) cells g−1 soil in 1–2 mm and 5.84 x 107(SE 2.4 x 106) cells g−1 in 2–4 mm size aggregates soil. Solid-pore interfaces influenced bacterial distribution at micro- and macroscale, whereas the effect of soil porosity on bacterial distribution varied according to three observation scales in different soil architectures. The influence of soil porosity on the distribution of bacteria in different soil architectures was observed mainly at the macroscale, relative to micro- and mesoscales. Experimental data suggest that the effect of pore geometry on the distribution of bacteria varied with the spatial scale, thus highlighting the need to consider an “appropriate spatial scale” to understand the factors that regulate the distribution of microbial communities in soils. The results obtained to date also indicate that the proposed method is a significant step towards a full mechanistic understanding of microbial dynamics in structured soils.

Characterization of Adipogenic Activity of House Dust Extracts and Semi-Volatile Indoor Contaminants in 3T3-L1 Cells.

Obesity and metabolic disorders are of great societal concern and generate significant human health care costs. Recently, attention has focused on the potential for environmental contaminants to act as metabolic disruptors. This study sought to evaluate the adipogenic activity of indoor house dust extracts and a suite of semivolatile organic chemicals (SVOCs) that are often ubiquitously detected in indoor environments. 3T3-L1 cells were exposed to extracts of indoor dust or individual SVOCs and assessed for triglyceride accumulation and preadipocyte proliferation. Ten of 11 house dust extracts exhibited significant triglyceride accumulation and/or proliferation at environmentally relevant levels (<20 μg of dust/well), and significant adipogenic activity was also exhibited by 28 of the SVOCs. Notably, pyraclostrobin, dibutyl phthalate, tert-butyl-phenyl diphenyl phosphate, and the isopropylated triaryl phosphates (ITPs) exhibited near maximal or supra-maximal triglyceride accumulation relative to the rosiglitazone-induced maximum. The adipogenic activity in house dust occurred at concentrations below EPA estimated child exposure levels, and raises concerns for human health impacts, particularly in children. Our results delineate a novel potential health threat and identify putative causative SVOCs that are likely contributing to this activity.

Characterization of Adipogenic Chemicals in Three Different Cell Culture Systems: Implications for Reproducibility Based on Cell Source and Handling

The potential for chemical exposures to exacerbate the development and/or prevalence of metabolic disorders, such as obesity, is currently of great societal concern. Various in vitro assays are available to assess adipocyte differentiation, though little work has been done to standardize protocols and compare models effectively. This study compares several adipogenic cell culture systems under a variety of conditions to assess variability in responses. Two sources of 3T3-L1 preadipocytes as well as OP9 preadipocytes were assessed for cell proliferation and triglyceride accumulation following different induction periods and using various tissue culture plates. Both cell line and cell source had a significant impact on potencies and efficacies of adipogenic chemicals. Gene expression analyses suggested that differential expression of nuclear receptors involved in adipogenesis underlie the differences between OP9 and 3T3-L1 cells; however, there were also differences based on 3T3-L1 cell source. Induction period modulated potency and efficacy of response depending on cell line and test chemical, and large variations were observed in triglyceride accumulation and cell proliferation between brands of tissue culture plates. Our results suggest that the selection of a cell system and differentiation protocol significantly impacts the detection of adipogenic chemicals, and therefore, influences reproducibility of these studies.

Assessment of risk to human health from simultaneous exposure to multiple contaminants in an artisanal gold mine in Serra Pelada, Pará, Brazil

Contamination of soil, water and plants caused by gold mining is of great societal concern because of the risk of environmental pollution and risk to human health. The aim of the present study was to evaluate the risk to human health from ingestion of As, Ba, Co, Cu, Cd, Cr, Ni, Pb, Se and Ni present in soil, sterile and mineralized waste, and water and plants at a gold mine in Serra Pelada, Pará, Brazil. Samples of soil, sterile and mineralized waste, water and plants were collected around an artisanal gold mine located in Serra Pelada. The mean concentrations of potentially toxic elements in the soil were higher than the soil quality reference values as defined in the legislation, which may be attributeable to past mining activities. Water from the area close to the mine exhibited As, Ba and Pb concentrations exceeding the reference values established by the World Health Organization, deemed unfit for human consumption. Plants exhibited high Pb concentrations, representing a food safety risk to the population. The mean hazard index (HI) values were below the acceptable limit (1.0) established by the United States Environmental Protection Agency, although the highest HI values observed for adults and children were higher than the respective acceptable limits. Environmental contamination and risk to human health were heterogeneous in the surroundings of the mine. Mitigation strategies need to be adopted to decrease the risks of contamination to the environment and to the local population.

Bidirectional Modulation of Alcohol-Associated Memory Reconsolidation through Manipulation of Adrenergic Signaling.

Alcohol addiction is a problem of great societal concern, for which there is scope to improve current treatments. One potential new treatment for alcohol addiction is based on disrupting the reconsolidation of the maladaptive Pavlovian memories that can precipitate relapse to drug-seeking behavior. In alcohol self-administering rats, we investigated the effects of bidirectionally modulating adrenergic signaling on the strength of a Pavlovian cue-alcohol memory, using a behavioral procedure that isolates the specific contribution of one maladaptive Pavlovian memory to relapse, the acquisition of a new alcohol-seeking response for an alcohol-associated conditioned reinforcer. The β-adrenergic receptor antagonist propranolol, administered in conjunction with memory reactivation, persistently disrupted the memory that underlies the capacity of a previously alcohol-associated cue to act as a conditioned reinforcer. By contrast, enhancement of adrenergic signaling by administration of the adrenergic prodrug dipivefrin at reactivation increased the strength of the cue-alcohol memory and potentiated alcohol seeking. These data demonstrate the importance of adrenergic signaling in alcohol-associated memory reconsolidation, and suggest a pharmacological target for treatments aiming to prevent relapse through the disruption of maladaptive memories.

S09: Models for drug abuse and drug depedence liability assessment

Drug abuse and drug dependence are problems of great societal concern. For the pharmaceutical industry, drug abuse and dependence liability present issues not only for patients but also for public health. Diversion of prescription drugs from hospitals and pharmacies for unprescribed and illegal use will bring increased restrictions regarding production, distribution and prescription for these drugs. In order to protect public health and reduce dependence potential in patients receiving prescription drugs, new drugs need to be assessed for abuse and dependence liability as mandated in guidelines by regulatory agencies like the US Food and Drug Administration (FDA), the European Medicines Agency (EMEA) and the Japanese Department of Health Education and Welfare. In the US the Drug Enforcement Administration (DEA) proposes legislation for classifying drugs in various schedules based on their predicted severity to produce abuse and dependence liability. This lecture will describe and discuss models for assessing drug abuse potential in rodents, primates and humans. Drug discrimination and self-administration models in rodents, primates and humans will be described and discussed. In addition, other in vitro and in vivo models signalling the need for further assessment will be described. A strategy for how the models may be used in drug abuse and dependence liability assessment will be suggested.

GIS, Cartography, and the “Third Culture”: Geographic Imaginations in the Computer Age*

Geographic information systems (GIS) and cartography have traditionally been regarded as fields for the study of techniques. Yet the past ten years have witnessed geographers' increasing intellectual engagement with GIS and cartography. This essay recaps the recent intellectual discourses on GIS and cartography and speculates on possible development in the near future. Geocomputation, spatially integrated social sciences, social informatics, information ecology, and humanistic GIScience are identified as five areas of intensive new research, and it is argued that creative imaginations under the milieu of the “third culture” are urgently needed to address the challenging issues in this new technological era. Whether geography will become an intellectually more vibrant discipline hinges on the extent to which we can rekindle geographic imaginations in this computer age via GIScience to address issues of great societal concern.