Making cities mental health friendly for adolescents and young adults.

Urban life shapes the mental health of city dwellers, and although cities provide access to health, education and economic gain, urban environments are often detrimental to mental health1,2. Increasing urbanization over the next three decades will be accompanied by a growing population of children and adolescents living in cities3. Shaping the aspects of urban life that influence youth mental health could have an enormous impact on adolescent well-being and adult trajectories4. We invited a multidisciplinary, global group of researchers, practitioners, advocates and young people to complete sequential surveys to identify and prioritize the characteristics of a mental health-friendly city for young people. Here we show a set of ranked characteristic statements, grouped by personal, interpersonal, community, organizational, policy and environmental domains of intervention. Life skills for personal development, valuing and accepting young people's ideas and choices, providing safe public space for social connection, employment and job security, centring youth input in urban planning and design, and addressing adverse social determinants were priorities by domain. We report the adversities that COVID-19 generated and link relevant actions to these data. Our findings highlight the need for intersectoral, multilevel intervention and for inclusive, equitable, participatory design of cities that support youth mental health.

Coupling coordination degree of healthcare resource supply, demand and elderly population change in China.

OBJECT: To analyze the trend of the coupling and coordination of the supply and demand of healthcare resources between the elderly population and healthcare resources in China during the period of 2012-2022, to reveal the impact of the growth of the elderly population on the relationship between the supply and demand of healthcare resources, and to put forward suggestions to improve the coupling and coordination between the supply and demand of healthcare resources and the elderly population, in order to cope with the challenges of an aging society. METHODS: By obtaining relevant data from authoritative data sources such as China Statistical Yearbook, Health and Health Statistics Yearbook, and the Chinese government website from 2012 to 2022, we constructed a comprehensive measurement index for the three systems of elderly population, healthcare resource supply, and healthcare resource demand; Using the entropy value method to assign weights to the indicators, combined with the coupling coordination degree model, to reveal the changes of the elderly population change and the supply and demand of medical and health resources; using ArcGIS technology, to study the spatial characteristics of the elderly population change and the supply and demand of medical and health resources. RESULTS: From 2012 to 2022, the supply and demand of healthcare resources and the variation of the elderly population in China show a continuous growth trend, and the comprehensive development level of the system gradually climbs from a low level to a high level. The fluctuation of coupling degree and coordination degree rises, although the coordination degree has always been lower than the coupling degree, but the distance between the coordination degree and the coupling degree gradually narrows with the passage of time. The coordination degree between population aging and medical and health resources development shows spatial heterogeneity in China, with the eastern region significantly higher than the western region/. CONCLUSIONS: The coupling degree between population aging and healthcare resource supply and demand in China from 2012 to 2022 shows a general upward trend from low coupling to medium-high coupling, but it is worth noting that even though the degree of coupling increases, the degree of coordination is still relatively lagging behind, suggesting that the government and relevant departments need to pay more attention to coordinated allocation and management of healthcare resources. At the same time, the spatial differences in the degree of coordination among provinces suggest that future policymakers should take regional differences into full consideration in policymaking and sustainable development.

The paradox of aging population and firm digital transformation in China.

Although a number researchers have acknowledged that the aging population inhibits firm digital transformation, others find it promoting digital transformation in some firms. As the relevant literature to clarify such paradox is still scare, this paper wants to fill the gap regarding the labor cost theory, the capital-skill complementarity hypothesis, and the human capital externality theory. Based on the empirical tests of Chinese A-share listed companies from 2001 to 2022, this study detected a U-shaped relationship between the aging population and digital transformation. In terms of the institutional environment, higher marketization strengthens the U-shaped relationship by making the slopes on either side of it steeper. However, higher minimum wage levels weaken the U-shaped relationship. In terms of firm strategy, firms with stronger marketing capabilities strengthened the U-shaped relationship. However, firms with higher customer concentration weakened the U-shaped relationship. Overall, we enriched scholarly understanding of the impact of the aging population on digital transformation and demonstrated the dual potential impact of aging populations. Instead of assuming they are detrimental to the economy and society, positive contributions in the form of innovation and progress for companies can be detected.

A coupled human-natural system analysis of freshwater security under climate and population change.

Limited water availability, population growth, and climate change have resulted in freshwater crises in many countries. Jordan's situation is emblematic, compounded by conflict-induced population shocks. Integrating knowledge across hydrology, climatology, agriculture, political science, geography, and economics, we present the Jordan Water Model, a nationwide coupled human-natural-engineered systems model that is used to evaluate Jordan's freshwater security under climate and socioeconomic changes. The complex systems model simulates the trajectory of Jordan's water system, representing dynamic interactions between a hierarchy of actors and the natural and engineered water environment. A multiagent modeling approach enables the quantification of impacts at the level of thousands of representative agents across sectors, allowing for the evaluation of both systemwide and distributional outcomes translated into a suite of water-security metrics (vulnerability, equity, shortage duration, and economic well-being). Model results indicate severe, potentially destabilizing, declines in freshwater security. Per capita water availability decreases by approximately 50% by the end of the century. Without intervening measures, >90% of the low-income household population experiences critical insecurity by the end of the century, receiving <40 L per capita per day. Widening disparity in freshwater use, lengthening shortage durations, and declining economic welfare are prevalent across narratives. To gain a foothold on its freshwater future, Jordan must enact a sweeping portfolio of ambitious interventions that include large-scale desalinization and comprehensive water sector reform, with model results revealing exponential improvements in water security through the coordination of supply- and demand-side measures.

Metapopulations with habitat modification.

Across the tree of life, organisms modify their local environment, rendering it more or less hospitable for other species. Despite the ubiquity of these processes, simple models that can be used to develop intuitions about the consequences of widespread habitat modification are lacking. Here, we extend the classic Levins metapopulation model to a setting where each of n species can colonize patches connected by dispersal, and when patches are vacated via local extinction, they retain a "memory" of the previous occupant-modeling habitat modification. While this model can exhibit a wide range of dynamics, we draw several overarching conclusions about the effects of modification and memory. In particular, we find that any number of species may potentially coexist, provided that each is at a disadvantage when colonizing patches vacated by a conspecific. This notion is made precise through a quantitative stability condition, which provides a way to unify and formalize existing conceptual models. We also show that when patch memory facilitates coexistence, it generically induces a positive relationship between diversity and robustness (tolerance of disturbance). Our simple model provides a portable, tractable framework for studying systems where species modify and react to a shared landscape.

The crucial role of genome-wide genetic variation in conservation.

The unprecedented rate of extinction calls for efficient use of genetics to help conserve biodiversity. Several recent genomic and simulation-based studies have argued that the field of conservation biology has placed too much focus on conserving genome-wide genetic variation, and that the field should instead focus on managing the subset of functional genetic variation that is thought to affect fitness. Here, we critically evaluate the feasibility and likely benefits of this approach in conservation. We find that population genetics theory and empirical results show that conserving genome-wide genetic variation is generally the best approach to prevent inbreeding depression and loss of adaptive potential from driving populations toward extinction. Focusing conservation efforts on presumably functional genetic variation will only be feasible occasionally, often misleading, and counterproductive when prioritized over genome-wide genetic variation. Given the increasing rate of habitat loss and other environmental changes, failure to recognize the detrimental effects of lost genome-wide genetic variation on long-term population viability will only worsen the biodiversity crisis.

Local adaptation of Mycobacterium tuberculosis on the Tibetan Plateau.

During its global dispersal, Mycobacterium tuberculosis (Mtb) has encountered varied geographic environments and host populations. Although local adaptation seems to be a plausible model for describing long-term host-pathogen interactions, genetic evidence for this model is lacking. Here, we analyzed 576 whole-genome sequences of Mtb strains sampled from different regions of high-altitude Tibet. Our results show that, after sequential introduction of a few ancestral strains, the Tibetan Mtb population diversified locally while maintaining strict separation from the Mtb populations on the lower altitude plain regions of China. The current population structure and estimated past population dynamics suggest that the modern Beijing sublineage strains, which expanded over most of China and other global regions, did not show an expansion advantage in Tibet. The mutations in the Tibetan strains showed a higher proportion of A > G/T > C transitions than strains from the plain regions, and genes encoding DNA repair enzymes showed evidence of positive selection. Moreover, the long-term Tibetan exclusive selection for truncating mutations in the thiol-oxidoreductase encoding sseA gene suggests that Mtb was subjected to local selective pressures associated with oxidative stress. Collectively, the population genomics of Mtb strains in the relatively isolated population of Tibet provides genetic evidence that Mtb has adapted to local environments.

The persistence of ancient settlements and urban sustainability.

We propose a dedicated research effort on the determinants of settlement persistence in the ancient world, with the potential to significantly advance the scientific understanding of urban sustainability today. Settlements (cities, towns, villages) are locations with two key attributes: They frame human interactions and activities in space, and they are where people dwell or live. Sustainability, in this case, focuses on the capacity of structures and functions of a settlement system (geography, demography, institutions) to provide for continuity of safe habitation. The 7,000-y-old experience of urbanism, as revealed by archaeology and history, includes many instances of settlements and settlement systems enduring, adapting to, or generating environmental, institutional, and technological changes. The field of urban sustainability lacks a firm scientific foundation for understanding the long durée, relying instead on narratives of collapse informed by limited case studies. We argue for the development of a new interdisciplinary research effort to establish scientific understanding of settlement and settlement system persistence. Such an effort would build upon the many fields that study human settlements to develop new theories and databases from the extensive documentation of ancient and premodern urban systems. A scientific foundation will generate novel insights to advance the field of urban sustainability.

Primary Care Access in Areas of the United States With Aging Populations.

The percentage of U.S. residents 65 years and older was 17% in 2020, and this number is expected to rise due to the aging of the baby boomer generation.1Although life expectancy fell between 2020 and 2021, the proportion of U.S. residents older than 65 years continues to increase.2This age group often has more medical comorbidities and prescription medications, increasing the demand for primary care access. Domestic migration (U.S. residents moving within the country) of this retirement-aged population further strains the primary care workforce in underserved areas.

[Life expectancy for the regions of the Northwestern Federal District. Part 2: Dynamics of old age threshold.]

The paper continues the study of the population ageing in the regions of the Northwestern Federal District. It characterized population ageing based on prospective ageing indicators that take into account remaining life expectancy. The dynamics of life expectancy (LE) at birth was analyzed. A computation and comparative analysis of the old age threshold for the regions that are part of the Northwestern Federal District have been carried out. A comparative analysis of ageing indicators - traditional and prospective (the proportion of the elderly and the share of the population above the old age threshold) was carried out. It has been found that there are no fundamental differences in the dynamics of life expectancy in older ages, as well as in the of old age threshold, between the regions considered. It is shown that for the male population in almost all regions in 2021, the value of the old age threshold is below 60 years, while for the female population the opposite inequality is observed. Thus, in 2021, the share of men over the old age threshold exceeds the proportion of the elderly in almost all regions considered, and for the female population, the share of the elderly is expected to be higher than the values of the prospective indicator.

[Demographic and professional risks of depopulation among working population in Russia: 14 years later (analytical review).]

The article presents a comparative analysis of the process of population aging in the context of demographic and professional risks of depopulation among working population in Russia. The values of the main medical and demographic indicators of population aging for Russia and developed countries were given. The results of UN forecasts, probabilistic forecasts of the total number and some characteristics of the age-sex structure for the population of the Russian Federation were analyzed. The state of demographic disadvantage in Russia and in the world was convincingly shown. Particular attention was paid to the consideration of the demographic risks of a reduction in the working-age population and an increase in the burden on the working-age population. The need for further research on the use of geroprotectors and modern gerontotechnologies as means and methods for preventing premature decline in work ability, slowing down the aging process of workers, reducing the mortality rate among working population and increasing professional longevity has been proven.

Dispersal increases ecological selection by increasing effective community size.

Selection and drift are universally accepted as the cornerstones of evolutionary changes. Recent theories extend this view to ecological changes, arguing that any change in species composition is driven by deterministic fitness differences among species (enhancing selection) and/or stochasticity in birth and death rates of individuals within species (enhancing drift). These forces have contrasting effects on the predictability of ecological dynamics, and thus understanding the factors affecting their relative importance is crucial for understanding ecological dynamics. Here we test the hypothesis that dispersal increases the relative importance of ecological selection by increasing the effective size of the community (i.e., the size relevant for competitive interactions and drift). According to our hypothesis, dispersal increases the effective size of the community by mixing individuals from different localities. This effect diminishes the relative importance of demographic stochasticity, thereby reducing drift and increasing the relative importance of selective forces as drivers of species composition. We tested our hypothesis, which we term the "effective community size" hypothesis, using two independent experiments focusing on annual plants: a field experiment in which we manipulated the magnitude of dispersal and a mesocosm experiment in which we directly manipulated the effective size of the communities. Both experiments, as well as related model simulations, were consistent with the hypothesis that increasing dispersal increases the role of selective forces as drivers of species composition. This finding has important implications for our understanding of the fundamental forces affecting community dynamics, as well as the management of species diversity, particularly in patchy and fragmented environments.

Climate change causes upslope shifts and mountaintop extirpations in a tropical bird community.

Montane species worldwide are shifting upslope in response to recent temperature increases. These upslope shifts are predicted to lead to mountaintop extinctions of species that live only near mountain summits, but empirical examples of populations that have disappeared are sparse. We show that recent warming constitutes an "escalator to extinction" for birds on a remote Peruvian mountain-high-elevation species have declined in both range size and abundance, and several previously common mountaintop residents have disappeared from the local community. Our findings support projections that warming will likely drive widespread extirpations and extinctions of high-elevation taxa in the tropical Andes. Such climate change-driven mountaintop extirpations may be more likely in the tropics, where temperature seems to exert a stronger control on species' range limits than in the temperate zone. In contrast, we show that lowland bird species at our study site are expanding in range size as they shift their upper limits upslope and may thus benefit from climate change.

Multisectoral Approach to Address Chikungunya Outbreaks Driven by Human Mobility: A Systematic Review and Meta-Analysis.

BACKGROUND: The role of human mobility in the epidemiology of emerging Aedes-transmitted viral diseases is recognized but not fully understood. The objective of this systematic review and meta-analysis was to examine how human mobility patterns are driving chikungunya outbreaks. METHODS: Literature was systematically reviewed for studies on chikungunya prevalence in countries/territories with high-level evidence of human mobility-driven outbreaks, based on: (1) emergence of chikungunya outbreaks with epidemic chikungunya virus genotypes among displaced/migrant populations and their hosting communities; and (2) identification of imported index case(s) with epidemic genotypes phylogenetically related to the genotypes circulating during emerging or subsequent outbreaks. RESULTS: The meta-analysis of extracted prevalence data revealed that a large proportion of the population in countries/territories afflicted by outbreaks is still at risk of infection during future outbreaks. On the other hand, approximately one-half of suspected chikungunya cases could be infected with other co-circulating acute febrile illnesses. CONCLUSIONS: We discussed in this paper how human mobility-driven chikungunya outbreaks can be addressed, and how the involvement of several sectors in addition to the health sector in multisectoral approaches (MSAs) is important for prevention and control of chikungunya and other Aedes-transmitted arboviral outbreaks.

A Bayesian Reconstruction of a Historical Population in Finland, 1647-1850.

This article provides a novel method for estimating historical population development. We review the previous literature on historical population time-series estimates and propose a general outline to address the well-known methodological problems. We use a Bayesian hierarchical time-series model that allows us to integrate the parish-level data set and prior population information in a coherent manner. The procedure provides us with model-based posterior intervals for the final population estimates. We demonstrate its applicability by estimating the long-term development of Finland's population from 1647 onward and simultaneously place the country among the very few to have an annual population series of such length available.

Evolution of dispersal in spatial population models with multiple timescales.

We study the evolutionary stability of dispersal strategies, including but not limited to those that can produce ideal free population distributions (that is, distributions where all individuals have equal fitness and there is no net movement of individuals at equilibrium). The environment is assumed to be variable in space but constant in time. We assume that there is a separation of times scales, so that dispersal occurs on a fast timescale, evolution occurs on a slow timescale, and population dynamics and interactions occur on an intermediate timescale. Starting with advection-diffusion models for dispersal without population dynamics, we use the large time limits of profiles for population distributions together with the distribution of resources in the environment to calculate growth and interaction coefficients in logistic and Lotka-Volterra ordinary differential equations describing population dynamics. We then use a pairwise invasibility analysis approach motivated by adaptive dynamics to study the evolutionary and/or convergence stability of strategies determined by various assumptions about the advection and diffusion terms in the original advection-diffusion dispersal models. Among other results we find that those strategies which can produce an ideal free distribution are evolutionarily stable.

Will We Soon Run Out of Water?

In 2000, the World population was 6.2 billion; it reached 7 billion in 2012 and should reach 9.5 billion (±0.4) in 2050 and 11 billion (±1.5) in 2100, according to UN projections. The trend after 2100 is still one of global demographic growth, but after 2060, Africa would be the only continent where the population would still increase. The amount of water consumed annually to produce the food necessary to meet the needs varies greatly between countries, from about 600 to 2,500 m3/year per capita, depending on their wealth, their food habits (particularly meat consumption), and the percentage of food waste they generate. In 2000, the total food production was on the order of 3,300 million tons (in cereal equivalents). In 2019, about 0.8 billion inhabitants of the planet still suffer from hunger and do not get the nutrition they need to be in good health or, in the case of children, to grow properly (both physically and intellectually). Assuming a World average water consumption for food of 1,300 m3/year per capita in 2000, 1,400 m3/year in 2050, and 1,500 m3/year in 2100, a volume of water of around 8,200 km3/year was needed in 2000, 13,000 km3/year will be needed in 2050, and 16,500 km3/year in 2100. Will that much water be available on earth? Can there be conflicts related to a food deficit? Some preliminary answers and scenarios for food production will be given from a hydrologist viewpoint.

Spatiotemporal matching between medical resources and population ageing in China from 2008 to 2017.

BACKGROUND: Globally, the increasingly severe population ageing issue has been creating challenges in terms of medical resource allocation and public health policies. The aim of this study is to address the space-time trends of the population-ageing rate (PAR), the number of medical resources per thousand residents (NMRTR) in mainland China in the past 10 years, and to investigate the spatial and temporal matching between the PAR and NMRTR in mainland China. METHODS: The Bayesian space-time hierarchy model was employed to investigate the spatiotemporal variation of PAR and NMRTR in mainland China over the past 10 years. Subsequently, a Bayesian Geo-Detector model was developed to evaluate the spatial and temporal matching levels between PAR and NMRTR at national level. The matching odds ratio (OR) index proposed in this paper was applied to measure the matching levels between the two terms in each provincial area. RESULTS: The Chinese spatial and temporal matching q-statistic values between the PAR and three vital types of NMRTR were all less than 0.45. Only the spatial matching Bayesian q-statistic values between the PAR and the number of beds in hospital reached 0.42 (95% credible interval: 0.37, 0.48) nationwide. Chongqing and Guizhou located in southwest China had the highest spatial and temporal matching ORs, respectively, between the PAR and the three types of NMRTR. The spatial pattern of the spatial and temporal matching ORs between the PAR and NMRTR in mainland China exhibited distinct geographical features, but the geographical structure of the spatial matching differed from that of the temporal matching between the PAR and NMRTR. CONCLUSION: The spatial and temporal matching degrees between the PAR and NMRTR in mainland China were generally very low. The provincial regions with high PAR largely experienced relatively low spatial matching levels between the PAR and NMRTR, and vice versa. The geographical pattern of the temporal matching between the PAR and NMRTR exhibited the feature of north-south differentiation.

The global decline of cheetah Acinonyx jubatus and what it means for conservation.

Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human-wildlife coexistence across large multiple-use landscapes.

Holocene fluctuations in human population demonstrate repeated links to food production and climate.

We consider the long-term relationship between human demography, food production, and Holocene climate via an archaeological radiocarbon date series of unprecedented sampling density and detail. There is striking consistency in the inferred human population dynamics across different regions of Britain and Ireland during the middle and later Holocene. Major cross-regional population downturns in population coincide with episodes of more abrupt change in North Atlantic climate and witness societal responses in food procurement as visible in directly dated plants and animals, often with moves toward hardier cereals, increased pastoralism, and/or gathered resources. For the Neolithic, this evidence questions existing models of wholly endogenous demographic boom-bust. For the wider Holocene, it demonstrates that climate-related disruptions have been quasi-periodic drivers of societal and subsistence change.