Increased Readiness for Water Splitting: NiO-Induced Weakening of Bonds in Water Molecules as Possible Cause of Ultra-Low Oxygen Evolution Potential

The development of non-precious metal-based electrodes that actively and stably support the oxygen evolution reaction (OER) in water electrolysis systems remains a challenge, especially at low pH levels. The recently published study has conclusively shown that the addition of haematite to H2SO4 is a highly effective method of significantly reducing oxygen evolution overpotential and extending anode life. The far superior result is achieved by concentrating oxygen evolution centres on the oxide particles rather than on the electrode. However, unsatisfactory Faradaic efficiencies of the OER and hydrogen evolution reaction (HER) parts as well as the required high haematite load impede applicability and upscaling of this process. Here it is shown that the same performance is achieved with three times less metal oxide powder if NiO/H2SO4 suspensions are used along with stainless steel anodes. The reason for the enormous improvement in OER performance by adding NiO to the electrolyte is the weakening of the intramolecular O─H bond in the water molecules, which is under the direct influence of the nickel oxide suspended in the electrolyte. The manipulation of bonds in water molecules to increase the tendency of the water to split is a ground-breaking development, as shown in this first example.

Competing double-exchange/super-exchange ordering for enhanced water oxidation kinetics

Competing double-exchange and super-exchange interactions yield rich chemistry for understanding robust oxygen evolution activity in Ru-doped lanthanum strontium manganite, with an overpotential of 300 mV at 10 mA cm-2 and a Tafel slope of 110 mV dec-1. Favourable redox potentials of Mn3+/Mn4+ and Ru4+/Ru5+ lead to improved charge transfer kinetics for OER activity.

Does club convergence matter in health outcomes? Evidence from Indian states

BACKGROUND

Population health is vital to a nation's overall well-being and development. To achieve sustainable human development, a reduction in health inequalities and an increase in interstate convergence in health indicators is necessary. Evaluation of the convergence patterns can aid the government in monitoring the health progress across the Indian states. This study investigates the progressive changes in the convergence and divergence patterns in health status across major states of India from 1990 to 2018.

METHODS

Sigma plots (σ), kernel density plots, and log t-test methods are used to test the convergence, divergence, and club convergence patterns in the health indicators at the state level.

RESULTS

The result of the sigma convergence suggests that life expectancy at birth has converged across all states. After 2006, however, the infant mortality rate, neonatal mortality rate, and total fertility rate experienced a divergence pattern. The study's findings indicate that life expectancy at birth converges in the same direction across all states, falling into the same club (Club One). However, considerable cross-state variations and evidence of clubs' convergence and divergence are observed in the domains of infant mortality rate, neonatal death rate, and total fertility rate. As suggested by the kernel density estimates, life expectancy at birth stratifies, polarizes, and becomes unimodal over time, although with a single stable state. A bimodal distribution was found for infant, neonatal, and total fertility rates.

CONCLUSIONS

Therefore, healthcare strategies must consider each club's transition path while focusing on divergence states to reduce health variations and improve health outcomes for each group of individuals.

Implementation of carbon pricing in an aging world calls for targeted protection schemes

Understanding the impact of climate fiscal policies on vulnerable groups is a prerequisite for equitable climate mitigation. However, there has been a lack of attention to the impacts of such policies on the elderly, especially the low-income elderly, in existing climate policy literature. Here, we quantify and compare the distributional impacts of carbon pricing on different age-income groups in the United States, the United Kingdom, and Japan and then on different age groups in other 28 developed countries. We find that the elderly are more vulnerable to carbon pricing than younger groups in the same income group. In particular, the low-income elderly and elderly in less wealthy countries face greater challenges because carbon pricing lead to both higher rate of increase in living cost among low-income elderly and greater income inequality within the same age group. In addition, the low-income elderly would benefit less than the younger groups within the same income group in the commonly proposed carbon revenues recycling schemes. The high vulnerability of the low-income elderly to carbon pricing calls for targeted social protection along with climate mitigation polices toward an aging world.

Trends in Research and Development for CO2 Capture and Sequestration

Technological and medical advances over the past few decades epitomize human capabilities. However, the increased life expectancies and concomitant land-use changes have significantly contributed to the release of ∼830 gigatons of CO₂ into the atmosphere over the last three decades, an amount comparable to the prior two and a half centuries of CO₂ emissions. The United Nations has adopted a pledge to achieve "net zero", i.e., yearly removing as much CO₂ from the atmosphere as the amount emitted due to human activities, by the year 2050. Attaining this goal will require a concerted effort by scientists, policy makers, and industries all around the globe. The development of novel materials on industrial scales to selectively remove CO₂ from mixtures of gases makes it possible to mitigate CO₂ emissions using a multipronged approach. Broadly, the CO₂ present in the atmosphere can be captured using materials and processes for biological, chemical, and geological technologies that can sequester CO₂ while also reducing our dependence on fossil-fuel reserves. In this review, we used the curated literature available in the CAS Content Collection to present a systematic analysis of the various approaches taken by scientists and industrialists to restore carbon balance in the environment. Our analysis highlights the latest trends alongside the associated challenges.

Small Area Estimation of Age-Specific and Total Fertility Rates in Bangladesh

Bangladesh has experienced a rapid national decline in fertility in recent decades, however, fertility rates vary considerably at the sub-national level (i.e., division). These variations are expected to be more pronounced at lower levels of geography (e.g., district level). However, routinely conducted demographic health surveys are designed for national estimates and do not have adequate samples to produce reliable estimate of fertility rates at lower levels of administrative units, particular when considering district level age-specific fertility rates. Data extracted from the Bangladesh Demographic Health Survey 2014 are used to derive direct estimates of age-specific fertility rates and associated smoothed standard errors. These are used as inputs for developing a small area model, which is expressed in a hierarchical Bayesian framework and fitted by Markov Chain Monte Carlo simulation. The model accounts for variation at different levels—women age-group, division, and district. The modeling results show large reductions in the estimated standards errors and provide consistent estimates of fertility at the detailed district age-specific level. There are significant differences in the fertility levels within and between districts and at the division level. Fertility rates are observed to be higher for Sylhet division and for women aged 20–24 years. We use geo-spatial maps of the fertility rates to visualize the variations over districts, and identify hot and cold-spots to have better targeted local level planning and policy decision making for further reductions in fertility rates in Bangladesh.

Why we need more methods for male contraception

The US Supreme Court decision against abortion has once again triggered the call for male contraception. However, in addition to existing methods, there are further reasons why pharmacological reversible easy-to-use male contraception should be available. Green activists and environmentalists have to recognize that overpopulation consume resources. Medical progress results in increasing life expectancy and must be combined with contraception. Sharing the risks of contraception among partners and "Reproductive Autonomy for All" are ethical issues. The resistance of the pharmacological industry to becoming partners in male contraception must be overcome by public financial subsidies and popular demand.

Response of microbial antibiotic resistance to pesticides: An emerging health threat

The spread of microbial antibiotic resistance has seriously threatened public health globally. Non-antibiotic stressors have significantly contributed to the evolution of bacterial antibiotic resistance. Although numerous studies have been conducted on the potential risk of pesticide pollution for bacterial antibiotic resistance, a systematic review of these concerns is still lacking. In the present study, we elaborate the mechanism underlying the effects of pesticides on bacterial antibiotic resistance acquisition as well as the propagation of antimicrobial resistance. Pesticide stress enhanced the acquisition of antibiotic resistance in bacteria via various mechanisms, including the activation of efflux pumps, inhibition of outer membrane pores for resistance to antibiotics, and gene mutation induction. Horizontal gene transfer is a major mechanism whereby pesticides influence the transmission of antibiotic resistance genes (ARGs) in bacteria. Pesticides promoted the conjugation transfer of ARGs by increasing cell membrane permeability and increased the proportion of bacterial mobile gene elements, which facilitate the spread of ARGs. This review can improve our understanding regarding the pesticide-induced generation and spread of ARGs and antibiotic resistant bacteria. Moreover, it can be applied to reduce the ecological risks of ARGs in the future.

Prevalence and determinants of unmet need for contraception among women in low and high-priority segments for family planning demand generation in Nigeria

BACKGROUND

Studies have identified various determinants of unmet need for contraception. These determinants cut across individual, household, community, and health facility levels. Despite this evidence, there remains a lack of information regarding differentials in the prevalence and determinants of unmet need for contraception among women in the low-priority segments (such as women of advanced reproductive age and women living with disabilities) and high-priority segments (such as adolescents, young adults, and unmarried women) for family planning demand generation, hence this study.

METHODS

The study design is cross-sectional. The study analyzed merged data from the individual, and persons recode of the 2018 Nigeria Demographic and Health Survey (NDHS). The samples analyzed are 5,147 women in the high-priority segment and 7,536 women in the low-priority segment. The outcome variable in the study was unmet need for contraception. The explanatory variables were selected at the individual, household, community, and facility levels. Statistical analyzes were performed using Stata 14. Three multilevel mixed-effects regression models were fitted. Model 1 was the empty model, while Model 2 included the sets of individual, household, and community variables. Model 3 controlled for the facility-level variables.

RESULTS

Findings show a higher prevalence of unmet need for contraception among women in the family planning low-priority segment compared to women in the family planning high-priority segment. Religion and desired family size were the two individual characteristics that significantly predicted the unmet need for contraception among women in the two segments. Sexual autonomy was the only household characteristic that predicted unmet need for contraception in both segments. There were differences in the community characteristics that predicted unmet need for contraception among women in the two segments.

CONCLUSION

The prevalence of unmet need for contraception is not the same among women in low and high family planning priority segments. The determinants also differ among women in the two segments. Though, women in different family planning segments have the same contraceptive needs of avoiding pregnancy when not needed, however, getting the needs satisfied requires that existing programs be further examined to develop initiatives that will resonate with each segment of reproductive-age women.

Scientists' warning on population

Humanity must commit to transformative change on all levels in order to address the climate emergency and biodiversity collapse. In particular, stabilizing and ultimately reducing the human population size is necessary to ensure the long-term wellbeing of our species and other life on Earth. We show how this transition can be accomplished in an equitable framework that promotes human rights. Specifically, we issue a global appeal for women and men to have at most one child and call for policy-makers to implement population policies that improve education for girls and young women and ensure the availability of high-quality family-planning services.

Fertility decision and its associated factors in Sub-Saharan Africa: a multilevel multinomial logistic regression analysis

Background

Fertility desire is one of the predictors of contraceptive behavior and fertility-related outcomes. However, information is scarce on individual and community-level factors of women’s fertility decisions in sub-Saharan Africa.

Objective

To assess fertility decisions and their associated factors in Sub-Saharan Africa.

Methods

The 35 Sub-Saharan African country’s most recent demographic and health surveys (DHS) data conducted from 2008 to 2020 was used. A total of 284,744 (weighted) married women were used for analysis. The proportion of fertility decisions with their 95%CI was estimated. To assess the factors associated with fertility decisions, both random effect and fixed effect analyses were conducted. In the fixed analysis, particularly in the multivariable analysis, adjusted relative risk ratio (aRRR) with its 95% confidence interval (CI) was reported and variables with a p-value < 0.05 were considered significant predictors of fertility decisions.

Results

In this study, 64.35% (95%CI: 64.2%, 64.5%) of the study participants had fertility desire. However, 5.4% (95%CI: 5.3, 5.5) of the study participants had undecided fertility behavior. In the multivariable analysis, desire for more children and undecided fertility desire were relatively lower among older women, women with primary, secondary, and higher education, working women, women who currently use contraceptives, women with a higher number of living children, women with higher parity, women from eastern and southern Africa, and women from wealthy households. While, the ideal number of children, women who had decision-making autonomy, and women from the rural residence were all associated with a relatively higher desire for more children and undecided fertility desire. Furthermore, respondents' education and sex of household head were associated with the desire for more children while media exposure was associated with undecided fertility desire.

Conclusion

In this study, around two-thirds of women had a desire for more children and only 5.4% of women had undecided fertility desires. Both individual and community-level factors were associated with both desires for more children and undecided fertility desires. As a result, the aforementioned factors should be considered while developing reproductive health programs.

Water electrolysis: from textbook knowledge to the latest scientific strategies and industrial developments

Replacing fossil fuels with energy sources and carriers that are sustainable, environmentally benign, and affordable is amongst the most pressing challenges for future socio-economic development. To that goal, hydrogen is presumed to be the most promising energy carrier. Electrocatalytic water splitting, if driven by green electricity, would provide hydrogen with minimal CO2 footprint. The viability of water electrolysis still hinges on the availability of durable earth-abundant electrocatalyst materials and the overall process efficiency. This review spans from the fundamentals of electrocatalytically initiated water splitting to the very latest scientific findings from university and institutional research, also covering specifications and special features of the current industrial processes and those processes currently being tested in large-scale applications. Recently developed strategies are described for the optimisation and discovery of active and durable materials for electrodes that ever-increasingly harness first-principles calculations and machine learning. In addition, a technoeconomic analysis of water electrolysis is included that allows an assessment of the extent to which a large-scale implementation of water splitting can help to combat climate change. This review article is intended to cross-pollinate and strengthen efforts from fundamental understanding to technical implementation and to improve the 'junctions' between the field's physical chemists, materials scientists and engineers, as well as stimulate much-needed exchange among these groups on challenges encountered in the different domains.

Hormonal Male Contraception: Getting to Market

Rates of unplanned pregnancies are high and stagnant globally, burdening women, families and the environment. Local limitations placed upon contraceptive access and abortion services exacerbate global disparities for women. Despite survey data suggesting men and their partners are eager for expanded male contraceptive options, efforts to develop such agents have been stymied by a paucity of monetary investment. Modern male hormonal contraception, like female hormonal methods, relies upon exogenous progestins to suppress the hypothalamic-pituitary-gonadal axis, in turn suppressing testicular testosterone production and sperm maturation. Addition of an androgen augments gonadotropin suppression, more effectively suppressing spermatogenesis in men, and provides androgenic support for male physiology. Previous contraceptive efficacy studies in couples have shown that hormonal male methods are effective and reversible. Recent efforts have been directed at addressing potential user and regulatory concerns by utilizing novel steroids and varied routes of hormone delivery. Provision of effective contraceptive options for men and women is an urgent public health need. Recognizing and addressing the gaps in our contraceptive options and engaging men in family planning will help reduce rates of unplanned pregnancies in the coming decades.

[Worldwide contraception]

The latest statistics concerning contraceptive use in the world have been published in 2019 by the United Nations. Among the 1.9 billion of women of reproductive age (15-49 years), 1.1 billion have a need for family planning. Among them, 190 millions are not using any contraception, although they wanted to avoid a pregnancy. There is a significant discrepancy among continents concerning the percentage of contraceptive use and the distribution of the different types of contraception. Female sterilization is the most widespread method of contraception since it represents 24% of all contraception methods used. Male condoms is used by 21% of couples. Thus, progress is still needed to disseminate effective, well tolerated and potentially reversible methods of contraception. Education of females, couples, medical and paramedical staff is one of the priority targets to improve contraception throughout the world.

Establishing a corporate social responsibility implementation model for promoting sustainability in the food sector: a hybrid approach of expert mining and ISM-MICMAC

Corporate social responsibility (CSR) is significantly related to food companies due to its prominent impact and greater dependency on the environment, economy, and society (triple bottom line - TBL). The CSR-related threats and opportunities' scale are shifting from single companies to networks and supply chains of the food sector. In this regard, this study empirically evaluates CSR initiatives by using Interpretive Structural Modeling (ISM) and Matrice d'Impacts Croisés Multiplication Appliqués à un Classement (MICMAC) methodology. So to develop an ISM-MICMAC-based framework, at first, CSR initiatives were chosen from existing literature with experts' advice. Later, MICMAC analysis results showed that "employee trainings and workshops" and "employee welfare and empowerment" are significant CSR initiatives that could help CSR's integration in the food sector of Pakistan, whereas CSR initiatives "community betterment" and "contribution towards economic development" proved least significant in the model. This study recommends that food sector firms should promote employee-based strategies in the firms. Moreover, the empirical findings of this study help to better understand CSR initiatives and their role in the implementation of CSR in the food sector of developing countries.

Demographic perspectives in research on global environmental change

The human population is at the centre of research on global environmental change. On the one hand, population dynamics influence the environment and the global climate system through consumption-based carbon emissions. On the other hand, the health and well-being of the population are already being affected by climate change. A knowledge of population dynamics and population heterogeneity is thus fundamental to improving our understanding of how population size, composition, and distribution influence global environmental change and how these changes affect population subgroups differentially by demographic characteristics and spatial distribution. The increasing relevance of demographic research on the topic, coupled with availability of theoretical concepts and advancement in data and computing facilities, has contributed to growing engagement of demographers in this field. In the past 25 years, demographic research has enriched climate change research-with the key contribution being in moving beyond the narrow view that population matters only in terms of population size-by putting a greater emphasis on population composition and distribution, through presenting both empirical evidence and advanced population forecasting to account for demographic and spatial heterogeneity. What remains missing in the literature is research that investigates how global environmental change affects current and future demographic processes and, consequently, population trends. If global environmental change does influence fertility, mortality, and migration, then population estimates and forecasts need to adjust for climate feedback in population projections. Indisputably, this is the area of new research that directly requires expertise in population science and contribution from demographers.

What's so troubling about 'voluntary' family planning anyway? A feminist perspective

Voluntary family planning is a key mainstay of demographic work and population policies. The 1994 International Conference on Population and Development (ICPD) signalled a decisive shift away from fertility reduction and target-setting to an emphasis on voluntary family planning as intrinsic to reproductive health and women's empowerment. Yet, criticisms of voluntary family planning programmes persist, interrogating how 'voluntariness' is understood and wielded or questioning the instrumentalization of women's fertilities in the service of economic and developmental goals. In this paper, I reflect on these debates with the aim of troubling the notion of voluntary family planning as an unambiguous good that enables equitable empowerment and development for all. Drawing on literature from cognate disciplines, I highlight how voluntariness is linked to social and structural conditions, and I challenge the instrumentalization of voluntary family planning as a 'common agenda' to solve 'development' problems. Engaging with this work can contribute to key concepts (e.g. 'voluntary') and measurements (e.g. autonomy), strengthening the collective commitment to achieving the ICPD and contributing to reproductive empowerment and autonomy. Through this intervention, I aim to help demographers see why some critics call for a reconsideration of voluntary family planning and encourage a decoupling of interventions from fertility reduction aims, instead centring human rights, autonomy, and reproductive empowerment.

[New frontiers in contraception research]

Improving current contraceptives and discover novel methods easy to use with added health benefits would meet the needs of couples who seek alternatives to current methods. New delivery systems target user-controlled, longer-acting options to provide choice, user's autonomy and improve compliance. Self-injections, microarray patches, pod rings able to deliver several molecules aim to prevent both pregnancies and sexually transmitted infections. Improved intrauterine systems and non-surgical permanent methods are also on the research agenda. The search for novel methods must continue, to curb maternal mortality led by multiple pregnancies and unsafe abortion, still a burden in many countries.

Urban Family Planning in Low- and Middle-Income Countries: A Critical Scoping Review

Health agendas for low- and middle-income countries (LMICs) should embrace and afford greater priority to urban family planning to help achieve a number of the global Sustainable Development Goals. The urgency of doing so is heightened by emerging evidence of urban fertility stalls and reversals in some sub-Saharan African contexts as well as the significance of natural increase over migration in driving rapid urban growth. Moreover, there is new evidence from evaluations of large programmatic interventions focused on urban family planning that suggest ways to inform future programmes and policies that are adapted to local contexts. We present the key dimensions and challenges of urban growth in LMICs, offer a critical scoping review of recent research findings on urban family planning and fertility dynamics, and highlight priorities for future research.

Economic effects of climate change on global agricultural production

Climate change seems to be larger, more complex and more unpredictable than any other environmental problem. This review deals with the economic effects of climate change on global agricultural production. The causes and consequences of climate change are very diverse, while populations in low-income countries are increasingly exposed to its negative effects. Supplying the population with food is possible with increased agricultural production, but this often occurs under unsustainable circumstances. Increased agricultural production is also one of the main sources of greenhouse gas emissions. In this research we highlight some of the important connections between climate change, population growth and agricultural production.

Major Trends in Population Growth Around the World

The world’s population continues to grow, albeit at a slower pace. The decelerating growth is mainly attributable to fertility declines in a growing number of countries. However, there are substantial variations in the future trends of populations across regions and countries, with sub-Saharan African countries being projected to have most of the increase. Population momentum plays an important role in determining the future population growth in many countries and areas where fertility is in a rapid transition. With declines in fertility, the world’s population is unprecedentedly aging, and the numbers of households with smaller sizes are growing. International migration is also on the rise since the beginning of this century. The world’s population is also urbanizing due to increased internal rural to urban migration. Nevertheless, there are uncertainties in future population growth, not only because there are uncertainties in the future trends in fertility, mortality, and migration, but also because there are many other factors that could affect these trajectories. International consensus on climate change and ecosystem protections may trigger population control policies, and the ongoing pandemic is likely to have some impact on mortality, migration, or even fertility.

Population and Climate Change: Consensus and Dissensus among Demographers

What role does population play in thinking about the problem of climate change and some of its solutions? In a survey conducted between February and April 2020, we asked European demographers to state their views on the relationship between climate change and population developments, and asked them to rate their concern about climate change and other socio-demographic issues. We found that climate change is at the top of the list of demographers' concerns, but that their sense of urgency with respect to taking action to redress global warming is not matched by their belief that population policy can make a crucial difference in reducing CO2 emissions: demographers are highly divided on the question whether the global population size should be reduced to lower CO2 emissions, as well as on the question whether family planning is an effective policy instrument.

Beyond growth and density: Recentring the demographic drivers of urban health and risk in the global south

Debates within urban studies concerning the relationship between urbanisation and infectious disease focus on issues of urban population growth, density, migration and connectivity. However, an effective long-term risk and wellbeing agenda, without which the threat of future pandemics cannot be mitigated, must also take account of demographic forces and changes as critical drivers of transmission and mortality risk within and beyond cities. A better understanding of the dynamics of fertility, mortality and changing age structures – key determinants of urban decline/growth in addition to migration – provides the foundation upon which healthier cities and a healthy global urban system can be developed. The study of how basic demographic attributes and trends are distributed in space and how they interact with risks, including those of infectious disease, must be incorporated as a priority into a post-COVID-19 urban public health agenda. This perspective concurs with recent debates in urban studies emphasising the demographic drivers of urban change. Moreover, it raises critical questions about the microbial and environmental emphasis of much research on the interface of urban health and governance.

Linking Urban Sprawl and Surface Urban Heat Island in the Teresina–Timon Conurbation Area in Brazil

Negative consequences of urban growing disparities usually lead to impressive levels of segregation, marginalization, and injustices, particularly in the context of climate change. Understanding the relations between urban expansion and social vulnerability has become extremely necessary for municipality management and sustainable urban development. Although the study of urbanization in Latin America (LA) has been well discussed, little attention has been given to how the population is affected by urban expansion-oriented movement after the 2008 economic crisis. Massive investments in infrastructure displaced the population to peripheral zones without adequate urban planning, which reflected in alteration in land use and land cover (LULC), followed by environmental impacts and public health issues caused by thermal discomfort, notably in semiarid regions. This paper aims to evaluate the effects of urban sprawl on the Teresina–Timon conurbation (TTC) area’s local population, located in Brazil’s northeast. Descriptive metrics (Moran’s I statistic and social vulnerability index) and orbital products derived from remote sensing—LULC and Land surface temperature (LST) maps—were applied. The results indicated that the housing program ‘My House My Life’ (PMCMV) had increased the values of land consumption per capita since 2009 significantly, showing a clear expanding trend. The gradual replacement of green areas by residential settlements resulted in an increased LST. The PMCMV program contributed substantially to a change in land use and land cover, which increased the extent of urbanized areas and changed the local microclimate.

Population growth and climate change: Addressing the overlooked threat multiplier

Demographic trends will play a role in determining the magnitude of climate disruption and the ability of societies to adapt to it. Yet policy makers largely ignore the potential of fertility changes and population growth when designing policies to limit climate disruption and lessen its impacts. Here we argue that rights-based policy interventions could decrease fertility rates to levels consistent with low population pathways. We review country and global level studies that explore the effects of low population pathways on climate change mitigation and adaptation. We then provide rights-based policy recommendations, such as the expansion of voluntary family planning programs that incorporate elements from successful past programs, and highlight current research gaps. In concert with policies that end fossil fuel use and incentivize sustainable consumption, humane policies that slow population growth should be part of a multifaceted climate response. These policies require attention from scientists, policy analysts and politicians.

A Scientist's Warning to humanity on human population growth

One needs only to peruse the daily news to be aware that humanity is on a dangerous and challenging trajectory. This essay explores the prospect of adopting a science-based framework for confronting these potentially adverse prospects. It explores a perspective based on relevant ecological and behavioral science. The objective is to involve concerned citizens of the world in this enterprise. The overall objective is to maintain Planet Earth as a favorable home for the future of humanity. Nine ecological principles explain one major aspect of what is happening and provide critical guidelines for appropriate action. Nine social behaviors explore how we might integrate social science insights with those from ecology. Twenty predictions are proposed based on these ecological and social science principles plus existing trends. If these trends are not vigorously and courageously confronted, we will likely be on track for the demise of our civilization. As we examine these challenges, our job will be especially complicated because a major segment of humanity is not prepared to accept evidence based on science, and this generates much resistance to any efforts directed toward effective control of current and future challenges. In these complex circumstances, we must remain as cooperative and optimistic as possible so that we can promote the needed willpower and ingenuity. This essay has broad support as it is a contribution to the Scientists' Warning to Humanity Program of the Alliance of World Scientists (Ripple et al., 2017).

Changing diets and the transformation of the global food system

An aspirational global food system is one that delivers across a suite of the Sustainable Development Goals (SDGs), including universal access to healthy diets, which can also codeliver on climate and environment SDGs. The literature has downplayed the relative contribution of dietary change to sustainable food systems. In this perspective article, we argue that the potential for positive transformational change in diets should not be underestimated, for two sets of reasons. First, the dynamism of diets over long-term and, especially, recent history shows the potential for rapid and widespread change, including toward more diverse and healthier diets. Second, contemporary behavioral research demonstrates promising tactics to influence consumers' dietary choices. Since the entire food system creates the circumstances of those choices, the most effective strategies to shift diets will involve multiple approaches that deliberately aim not just to influence consumers themselves but also to incentivize all actors in the food systems, taking into account multiple agendas and values. The effectiveness of actions will depend on the political economy at local, national, and global levels. Overall, there are reasons to be hopeful about the potential for accelerated global dietary change, given both historic trends and the growing suite of tools and approaches available.

Snakes and ladders: World development pathways' synergies and trade-offs through the lens of the Sustainable Development Goals

This paper takes three global visions of world development to 2050 and quantifies their implications for sustainable progress employing the metrics of the Sustainable Development Goals (SDGs). The SDG outcomes are structured through the interconnectivities of the three 'wedding cake' layers of 'economy', 'society' and 'biosphere', as posited by the Stockholm Resilience Centre. The key policy contribution is to quantify the resulting SDG synergies and trade-offs, whilst also decomposing and calculating the part-worth of the market drivers which contribute to these outcomes. The paper employs a global economic simulation model that combines rational market behaviour with environmental constraints (MAGNET) and is further extended with an SDG metrics module. A 'non-sustainable' world reveals trade-offs between economy and biosphere SDGs, with population growth of particular concern to a safe planetary operating space in the world's poorest regions. Sustainable visions could reduce natural resource pressures and emissions and meet energy requirements at potentially limited economic cost. Notwithstanding, these futures do not address income inequalities and potentially increase food security concerns for the most vulnerable members of society. Consequently, developed region led international cooperation and in-kind income transfers to developing countries, constitutes a necessary prerequisite to help remedy the SDG trade-offs exhibited within the more sustainable global pathways.

Snakes and ladders: World development pathways' synergies and trade-offs through the lens of the Sustainable Development Goals

This paper takes three global visions of world development to 2050 and quantifies their implications for sustainable progress employing the metrics of the Sustainable Development Goals (SDGs). The SDG outcomes are structured through the interconnectivities of the three 'wedding cake' layers of 'economy', 'society' and 'biosphere', as posited by the Stockholm Resilience Centre. The key policy contribution is to quantify the resulting SDG synergies and trade-offs, whilst also decomposing and calculating the part-worth of the market drivers which contribute to these outcomes. The paper employs a global economic simulation model that combines rational market behaviour with environmental constraints (MAGNET) and is further extended with an SDG metrics module. A 'non-sustainable' world reveals trade-offs between economy and biosphere SDGs, with population growth of particular concern to a safe planetary operating space in the world's poorest regions. Sustainable visions could reduce natural resource pressures and emissions and meet energy requirements at potentially limited economic cost. Notwithstanding, these futures do not address income inequalities and potentially increase food security concerns for the most vulnerable members of society. Consequently, developed region led international cooperation and in-kind income transfers to developing countries, constitutes a necessary prerequisite to help remedy the SDG trade-offs exhibited within the more sustainable global pathways.

When is fertility too low or too high? Population policy preferences of demographers around the world

When does fertility in a country become so low or so high that a government needs to intervene? This paper sheds light on this population policy question, based on a worldwide survey among demographers. We examine how professionals' policy preferences regarding fertility levels are affected by their views on the impacts of population growth/decline and by fertility in their country of residence. The median respondent suggests intervention once fertility goes below 1.4 children or above 3.0. Three results stand out: first, demographers who are concerned about the carrying capacity of the earth are more willing to intervene than those who are less concerned. Second, the context of decision-making matters: experts living in high-fertility countries are more set on intervention than those living in low-fertility countries, but their threshold fertility level is also higher. Third, political orientation matters: right-leaning demographers are more set on government intervention than left-leaning demographers.

Human fertility in relation to education, economy, religion, contraception, and family planning programs

Background

The world population is expected to increase greatly this century, aggravating current problems related to climate, health, food security, biodiversity, energy and other vital resources. Population growth depends strongly on total fertility rate (TFR), but the relative importance of factors that influence fertility needs more study.

Methods

We analyze recent levels of fertility in relation to five factors: education (mean school years for females), economy (Gross Domestic Product, GDP, per capita), religiosity, contraceptive prevalence rate (CPR), and strength of family planning programs. We compare six global regions: E Europe, W Europe and related countries, Latin America and the Caribbean, the Arab States, Sub-Saharan Africa, and Asia. In total, 141 countries are included in the analysis. We estimate the strength of relationships between TFR and the five factors by correlation or regression and present the results graphically.

Results

In decreasing order of strength, fertility (TFR) correlates negatively with education, CPR, and GDP per capita, and positively with religiosity. Europe deviates from other regions in several ways, e.g. TFR increases with education and decreases with religiosity in W Europe. TFR decreases with increasing strength of family planning programs in three regions, but only weakly so in a fourth, Sub-Saharan Africa (the two European regions lacked such programs). Most factors correlated with TFR are also correlated with each other. In particular, education correlates positively with GDP per capita but negatively with religiosity, which is also negatively related to contraception and GDP per capita.

Conclusions

These results help identify factors of likely importance for TFR in global regions and countries. More work is needed to establish causality and relative importance of the factors. Our novel quantitative analysis of TFR suggests that religiosity may counteract the ongoing decline of fertility in some regions and countries.

Heat Waves, the New Normal: Summertime Temperature Extremes Will Impact Animals, Ecosystems, and Human Communities

A consequence of climate change is the increased frequency and severity of extreme heat waves. This is occurring now as most of the warmest summers and most intense heat waves ever recorded have been during the past decade. In this review, I describe the ways in which animals and human populations are likely to respond to increased extreme heat, suggest how to study those responses, and reflect on the importance of those studies for countering the devastating impacts of climate change.

Aging Human Populations: Good for Us, Good for the Earth

As the nations of the world grapple with the task of creating sustainable societies, ending and in some cases reversing population growth will be necessary to succeed. Yet stable or declining populations are typically reported in the media as a problem, or even a crisis, due to demographic aging. This is misguided, as economic analyses show that the costs connected with aging societies are manageable, while the economic, social, and environmental benefits of smaller populations are substantial. Earth's human-carrying capacity has been exceeded; hence, population growth must end and aging societies are unavoidable. They should be embraced as part of a just and prosperous future for people and the other species with whom we share our planet.