Age Structure Research Articles

Gender and ethnic diversity and wage gaps in the Canadian chiropractic workforce

BackgroundAs health systems worldwide continue to face health workforce challenges exacerbated by the Covid-19 pandemic, chiropractors can play an important role in meeting increasing needs for rehabilitation services. However, limited evidence from some countries suggests the chiropractic workforce does not reflect the diversity of the population it serves. This observational study quantifies the chiropractor workforce in Canada in gender and ethnocultural composition and earnings, as tracers of equity and inclusion within this healthcare profession.MethodsWe used 2021 population census data with integrated administrative income tax records to identify and characterize chiropractic practitioners aged 25–54. Following a descriptive analysis, multivariate regression and Blinder-Oaxaca decomposition methods were applied to assess gender and ethnic earnings differences, adjusting for a range of professional and personal factors.ResultsThe chiropractic workforce was underrepresented regarding women (44.5% versus 50.6% of the total population) and visible minorities (20.0% versus 26.5%). Despite similar levels of education, women’s (unadjusted) earnings averaged 77.1 cents for every dollar earned by men in pandemic-affected 2020, narrowing slightly from 76.7 cents in 2019. Regression results showed significant earnings differences by gender and by ethnocultural identity, adjusting for other factors. An unexplainable gender wage gap persisted in the decomposition analysis, with women earning 6% less than men due to factors that could not be explained by differences in age structure or part-time work, pointing to additional contributing but unmeasured structural dynamics.ConclusionSignificant earnings disparities by gender and ethnicity among chiropractors emphasize the need for equity-oriented initiatives in leadership opportunities and compensation structures, to help influence the attractiveness of the profession to new talent.

Effects of population aging on quality of life and disease burden: a population-based study

BackgroundAs population aging intensifies, it becomes increasingly important to elucidate the casual relationship between aging and changes in population health. Therefore, our study proposed to develop a systematic attribution framework to comprehensively evaluate the health impacts of population aging.MethodsWe used health-adjusted life expectancy (HALE) to measure quality of life and disability-adjusted life years (DALY) to quantify the burden of disease for the population of Guangzhou. The HALE and DALY projections were generated using both the Bayesian age-period-cohort models and the population prediction models. Changes in HALE and DALY between 2010–2020 and 2020–2030 were decomposed to isolate the effects of population aging. Three scenarios were analyzed to examine the relative relationship between disease burden and population aging. In Scenarios 1 and 2, the disease burden rates in 2030 were assumed to either remain at 2020 levels or follow historical trends. In Scenario 3, it was assumed that the absolute numbers of years of life lost (YLL) and years lived with disability (YLD) in 2030 would remain unchanged from the 2020 levels.ResultsBetween 2010 and 2020, 56.24% [69.73%] of the increase in male [female, values in brackets] HALE was attributable to the mortality effects in the population aged 60 and over, while − 3.74% [− 9.29%] was attributable to the disability effects. The increase in DALY caused by changes in age structure accounted for 72.01% [46.68%] of the total increase in DALY. From 2020 to 2030, 61.43% [69.05%] of the increase in HALE is projected to result from the mortality effects in the population aged 60 and over, while − 3.88% [4.73%] will be attributable to the disability effects. The increase in DALY due to changes in age structure is expected to account for 102.93% [100.99%] of the total increase in DALY. In Scenario 1, YLL are projected to increase by 45.0% [54.7%], and YLD by 31.8% [33.8%], compared to 2020. In Scenario 2, YLL in 2030 is expected to decrease by − 2.9% [− 1.3%], while YLD will increase by 12.7% [14.7%] compared to 2020. In Scenario 3, the expected YLL rates and YLD rates in 2030 would need to be reduced by 15.3% [15.4%] and 15.4% [15.6%], respectively, compared to 2020.ConclusionsThe disability effects among the elderly population hinder improvements in quality of life, while changes in age structure are the primary driver of disease burden accumulation. To mitigate the excess disease burden caused by population aging, it is essential to achieve a reduction of more than 15% in the disease burden by 2030 compared to 2020. Our proposed attribution framework evaluates the health impacts of population aging across two dimensions: quality of life and disease burden. This framework enables comparisons of these effects over time and across different regions.

Demography and homing behavior in the poorly-known Philippine flat-headed frog Barbourula busuangensis (Anura: Bombinatoridae)

The flat-headed frog, Barbourula busuangensis, is a poorly known, riverine species, endemic to the province of Palawan in the Philippines. We applied capture-mark-recapture (CMR) methods to follow individuals at two sites (Malbato and San Rafael) in the island of Busuanga over 10 months in 2022–2023. We used passive internal transponders (PITs) to mark adult and subadults and single-colored visual internal elastomers (VIEs) for cohorts of juveniles. From a total of 196 frogs PIT-tagged in Malbato and 144 in San Rafael, we obtained overall recapture rates of 49% and 60% respectively. We used the POPAN formulation in MARK software to estimate abundance, survival, movement, and age-class demographics. Our best model estimated an average population size of 268 frogs at Malbato and 232 at San Rafael, and constant survival probabilities (mean ≥ 0.97) at both sites. When adding age classes to the model, abundance of adults was always higher than that of subadults producing an age structure dominated by adults at both sites. Growth rates decreased significantly with body size, being higher in juveniles (1.51 mm/month) and subadults (1.56 mm/month) than in adult frogs (0.60 mm/month). At these growth rates frogs may reach adulthood at 2.5 years, with the oldest individuals likely being over 11 years old. CMR data confirmed site fidelity, and translocation experiments revealed that frogs have the ability to home when displaced 10–50 m upstream and downstream from their original capture site. This is the first long-term study of B. busuangensis using robust field and analysis methods. Our data suggest that B. busuangensis is stable at present in Busuanga, with long-lived adults and dispersing subadults. We expect that these data may serve as baseline of current population abundance, age structure and growth rates which are factors that tend to be affected when species are threatened. In this way it may help researchers and conservation practitioners detect potential changes that may occur as this species confronts the challenges of the Anthropocene.

Chronic RNA G-quadruplex Accumulation in Aging and Alzheimer's Disease.

As the world population ages, new molecular targets in aging and Alzheimer's Disease (AD) are needed to combat the expected influx of new AD cases. Until now, the role of RNA structure in aging and neurodegeneration has largely remained unexplored. In this study, we examined human hippocampal postmortem tissue for the formation of RNA G-quadruplexes (rG4s) in aging and AD. We found that rG4 immunostaining strongly increased in the hippocampus with both age and with AD severity. We further found that neurons with accumulation of phospho-tau immunostaining contained rG4s, that rG4 structure can drive tau aggregation, and that rG4 staining density depended on APOE genotype in the human tissue examined. Combined with previous studies showing the dependence of rG4 structure on stress and the extreme power of rG4s at oligomerizing proteins, we propose a model of neurodegeneration in which chronic rG4 formation is linked to proteostasis collapse. These morphological findings suggest that further investigation of RNA structure in neurodegeneration is a critical avenue for future treatments and diagnoses.

Trends and analysis of risk factor differences in the global burden of chronic kidney disease due to type 2 diabetes from 1990 to 2021: A population-based study.

Chronic kidney disease (CKD) is a significant contributor to the global burden of disease. Among its causes, chronic kidney disease due to type 2 diabetes (CKD-T2D) is the primary subtype. This study aims to provide an updated assessment of the global disease burden of CKD-T2D from 1990 to 2021. It will analyse the trends in the global burden of CKD-T2D and the differences in risk factors, as well as project changes over the next 15 years. The data for this study were derived from the Global Burden of Disease, Injuries, and Risk Factors Study (GBD) 2021. Estimates of prevalence, incidence, deaths and disability-adjusted life years (DALYs) for CKD-T2D, along with their 95% uncertainty intervals (UIs), were extracted. The trends in CKD-T2D burden from 1990 to 2021 were analysed from overall and local perspectives. An age-period-cohort model was used to estimate the age, period and cohort effects on the prevalence and incidence of CKD-T2D between 1990 and 2021. A decomposition analysis was conducted to assess the contribution of population size, age structure and epidemiological changes to the burden of CKD-T2D. Population-attributable fractions were determined for each risk factor, and a difference analysis was conducted. Additionally, projections were made regarding changes in the burden of CKD-T2D over the next 15 years. In 2021, the global burden of CKD-T2D remained significant, with a total of 107 559 955 cases. The age-standardized prevalence rate (ASPR) was 1259.63 per 100 000 people. The age-standardized incidence rate (ASIR) was 23.07 per 100 000 people, and the age-standardized death rate (ASDR) was 5.72 per 100 000 people. The age-standardized disability-adjusted life years (DALYs) was 131.08 per 100 000. The global burden of CKD-T2D showed variation across different socio-demographic index (SDI) regions. In 2021, the overall burden of CKD-T2D continued to rise, with the age effect increasing with age. Both prevalence and incidence risks showed an upward trend over time. Decomposition analysis indicated that population growth and ageing were the primary contributors to the global burden of DALYs related to CKD-T2D. Metabolic risk factors such as high fasting plasma glucose and high body mass index (BMI) are the most significant attributable risk factors. It is projected that by 2036, the trends in ASPR, ASIR, ASDR and age-standardized DALYs will stabilize. However, ASIR and age-standardized DALYs are expected to continue rising, and the number of cases of prevalence, incidence, mortality and DALYs will persist in their upward trend. CKD-T2D imposes a significant global disease burden, with health disparities and unequal disease outcomes continuing to worsen across countries and regions due to differences in socio-economic development levels. This burden is primarily driven by population growth, ageing and metabolic risks such as obesity, hyperglycaemia and hypertension. Although the rate of increase in disease burden may slow over the next 15 years, the number of cases is expected to rise substantially. Therefore, enhancing prevention, early screening and effective treatment interventions, particularly in high-risk areas, is crucial for reducing the disease burden and narrowing health disparities.

Comparison of sickness absences across industries: A cross-sectional study using the JILPT Data Archive

Assessing the risk of employee health problems according to firm characteristics (e.g., industry) can be used by companies to identify groups of workers with health problems and develop health-related policies. Previous studies have examined differences in the prevalence of diseases across industries; however, studies using sickness absences, which reduce productivity, are scarce. The purpose of this study was to identify differences in sickness absence rates across industries. With permission for secondary use of archived data from the Japan Institute for Labor Policy and Training (JILPT), we obtained data from private companies with 50 or more regular employees nationwide. Negative binomial regression was conducted using the number of sickness absences attributed to mental health, cancer, lifestyle-related diseases (e.g., diabetes, hypertension, heart disease, cerebrovascular disease), and intractable diseases as the objective variables. The results were confirmed by an ordinal logistic regression. Firm characteristics other than industry were adjusted for firm size, age structure, medical examinations, labor unions, and flexible work systems. The incidence of sickness absences due to mental health was high in the information and communications, medical care/welfare, and education/learning support industries because of lifestyle-related diseases, and heart disease was high in the transportation/postal industry. Cancer was high in the medical care/welfare industry. While older worker age groups had a lower incidence of mental health issues, a higher incidence of physical illnesses, excluding intractable diseases, was observed. The presence of a labor union was associated with sickness absences due to mental health, cancer, and cerebrovascular disease, and the availability of a flexible work system was associated with sickness absences due to mental health and heart disease. The three industries with a high incidence of mental health leave had a high percentage of professional/technical workers and a common background of heavy workloads. In addition, role ambiguity, particularly in the education and medical industries, could lead to stress. The association between the transportation/postal industry and sickness absences due to lifestyle-related diseases and heart disease was probably influenced by work style and lifestyle, whereas the association between the medical care/welfare industry and sickness absences due to cancer was probably influenced by the high percentage of women in this industry. This study could not be adjusted for several variables examined in other studies, such as sex, and caution should be exercised when interpreting the results, especially regarding absences due to cancer.

Honouring Age: The Social Dynamics of Age Structure in 1 Timothy, written by Mona Tokarek LaFosse

Honouring Age: The Social Dynamics of Age Structure in 1 Timothy, written by Mona Tokarek LaFosse

Spatiotemporal characteristics and influencing factors of non-CO2 greenhouse gas emission intensity from China's livestock sector.

The livestock sector is a major source of non-CO2 greenhouse gas (GHG). As China has the world's largest livestock production, analyzing factors influencing GHG emission intensity of livestock (GEIL) is crucial for guiding its emission reduction policies. Yet, most current studies on livestock GHG focus on emission amount (GEAL) over GEIL, neglecting comprehensive utilization of spatial econometric models. Furthermore, the influencing factors mainly focus on population, economic level, urbanization, and industrial structure, while the exploration of factors such as technological innovation, consumers' age structure, and industrial agglomeration remains insufficient. This study first applied the standard deviation ellipse (SDE) model to describe the spatiotemporal evolution of GEAL and GEIL across 31 Chinese provinces from 2006 to 2022. Then, using extended STIRPAT theory, we analyzed GEIL's influencing factors with exploratory spatial data analysis (ESDA) and the geographically and temporally weighted regression (GTWR) model. The results showed that: (1) GEAL was concentrated in resource-rich grassland pastoral and grain-producing areas. Provincial GEAL trends varied, while national GEAL declined rapidly and then fluctuated slightly. Cattle, pigs, and sheep/goats contributed the most to GEAL. (2) GEIL significantly decreased nationwide and provincially, with Tibet having the highest reduction rate but still leading in GEIL. (3) GEAL followed a northeast-southwest distribution, whereas GEIL exhibited an east (slightly north) to west (slightly south) pattern. (4) Spatial analysis revealed significant GEIL clustering, with higher values in western provinces and lower in central and eastern regions. (5) Population scale, urbanization, age structure, proportion of ruminant animal production value, location quotient of livestock, employment income per capita of agricultural personnel, patent-granted intensity, and educational level in rural areas had diverse spatiotemporal impacts on GEIL across provinces. Tailored emission reduction policies and regional collaborative governance are recommended.

Carbon footprint heterogeneity across elderly groups in China

Abstract Assessing the elderly’s environmental impact is crucial as aging deepens. This paper incorporates age heterogeneity and urban-rural heterogeneity within the elderly into the study of aging’s impact on the environment, dividing the elderly population into four subgroups. Utilizing an environmentally extended multi-region input-output(EE-MRIO) model and data from 12,000 households, the carbon footprints of four subgroups was calculated. Findings reveal significant urban-rural and age-related heterogeneities in carbon emissions among those aged 60 and above. Urban elderly have higher per capita carbon footprints than rural elderly, and ‘the younger elderly’ have higher footprints than ‘the oldest old’. This heterogeneity extends to carbon footprint’s distribution: Urban elderly lean towards enjoyable consumption, while rural elderly prioritize survival. ‘The younger elderly’ have a greater carbon footprint from transport. This paper nests Chinese and global EE-MRIO, showing that global economies are more impacted by China’s elderly demand than mainland China itself. Furthermore, urban-rural structure has a greater impact on global carbon emissions compared to age structures.

Great Tit (Parus major) Nestlings Have Longer Telomeres in Old-Growth Forests Than in Young Forests.

Modification and deterioration of old-growth forests by industrial forestry have seriously threatened species diversity worldwide. The loss of natural habitats increases the concentration of circulating glucocorticoids and incurs chronic stress in animals, influencing the immune system, growth, survival, and lifespan of animals inhabiting such areas. In this study, we tested whether great tit (Parus major) nestlings grown in old-growth unmanaged coniferous forests have longer telomeres than great tit nestlings developing in young managed coniferous forests. This study showed that the patches of young managed coniferous forests had lower larval biomass than old-growth forests. Since insect larvae are the preferred food for great tit nestlings, the shortage of food may divert energy resources away from growth, which can show up as physiological stress, often raising the heterophil/lymphocyte (H/L) ratio. The H/L ratio revealed a significant difference in stress levels, being the highest in great tit nestlings developing in young-managed pine forests. We also found that the development of great tit nestlings in young managed forests had significantly shorter telomeres than in old-growth forests. Although nestling survival did not differ between the habitats, nestlings growing up in old-growth forests had greater telomere lengths, which can positively affect their lifespan. Our results suggest that the forest habitats affected by industrial forestry may represent ecological traps, as the development of young birds in deteriorated environments can affect the age structure of populations.

Analyzing patterns of accessibility to schools: A gravitational metrics study in València

<p>A gravity-based accessibility metric, the Two-Step Floating Catchment Area (2SFCA) enhanced with gaussian smoothing, is proposed to clarify the distribution of opportunities for compulsory education. Along with the physical locations of the homes and schools, the metric considers the population age structure and capacity to measure the population's accessibility to school services. The application of the 2SFCA within the '15-minute city' model and the analysis of València's urban environment revealed two main findings. First, the distribution of the accessibility scores after a spatial autocorrelation analysis closely reflected the per capita income across the city, irrespective of the type of school and level of compulsory education considered. Second, for most school age children, accessing a charter school is easier than access to a public school for primary and secondary education. The 2SFCA metric appears to adequately capture the uneven spatial distribution of educational opportunities, thus offering new insights into some of the forces the drive school segregation processes and their territorial foundations.</p>

Molecular dynamics analysis for aggregation phenomenon of aged asphalt and depolymerisation mechanism of regenerants

ABSTRACT The depolymerisation mechanism of various regenerants, when applied to the aged asphalt aggregate structure, was investigated to provide insights for the design and development of regenerants. This study focused on the molecular aggregation of the regenerant-aged asphalt system using molecular dynamics simulation technology. Simulation showcased that the uneven charge distribution in asphaltene molecules and the absence of charge in the central region are prerequisites for the electrostatic attraction of asphaltene molecules, which significantly affects their aggregation, and asphaltene molecules in heavy-aged asphalt are prone to forming stable aggregation structures. Among the four components of aged asphalt, asphaltene molecules exhibited the most significant self-aggregation, followed by saturates, while resin and aromatic molecules showed relatively weaker self-aggregation. Low temperatures encouraged aggregation, whereas high temperatures discouraged it, and ageing elevated the molecular self-aggregation, intensifying with the progression of asphalt ageing. Regenerants improved the depolymerisation of asphaltene aggregates, and fatty acid glycerides presented the most effective depolymerisation, followed by aromatic hydrocarbons and alkanes, while glycerol’s performance was the least effective. To choose regenerant composition materials, those with low electrical potential energy, weak polarity, low polar functional group content or non-polarity should be selected to ensure superior depolymerisation, permeation fusion, and regeneration effects.

Age determination of the wildcat (Felis silvestris): a case study of a sample from the North-Western Black Sea region (Ukraine)

In recent decades, the wildcat (Felis silvestris) population has been increasing along the eastern edge of its range in Ukraine, associated with the recolonisation of territories previously inhabited by the species. An essential aspect of analysing this process is studying population dynamics, including sex and age structures. Knowing the individual age of animals is a crucial prerequisite for investigating many aspects of their life cycle and population dynamics. This information is particularly important for Felis silvestris, a rare species included in international and national lists of protected animals, for the conservation and management of its populations. This necessitates the verification of age determination methods in specific Felis silvestris populations, particularly in the south-western regions of Ukraine. To determine the age of wildcats, we employed both traditional, non-invasive methods—such as analysing suture obliteration and dental morphometric characters—and methods requiring partial tooth destruction, such as studying changes in dentin volume and cementum in the root of the canines. Cementochronology was found to be the only method allowing the wildcat population to be divided into seven year classes. Cement deposition primarily occurs at the apical tip of the canine root, allowing the use of only the lower third of the tooth for analysis. This is particularly important when working with collection materials of rare species. In the first year of life (0+), dentin fills no more than 20% of the pulp cavity width. In subsequent year classes, dentin deposition occupies at least 70% of the pulp cavity volume, enabling a clear division of the wildcat population into two groups: young (0+) and older individuals. The distance between the enamel at the neck of the canine and the edge of its alveolus is an effective tool for distinguishing young and adult individuals. The analysis of alveolar recession relative to the neck enamel can be considered a promising method for determining age groups in wildcats, including both deceased and living individuals. The use of basicranial sutures of the skull was found to be less informative: the sutures at the skull base ossify late, while the obliteration between the maxilla and premaxilla in the nasal area is only partially expressed.

Genetic structure and demographic analysis of a true single-population species, Camellia azalea

Single-population species (SPS) consist of only one natural population and often are at high risk of extinction. Although almost all species must go through this special stage in their evolutionary process, there is little understanding of how SPS survives. Camellia azalea C. F. Wei is a typical SPS, and has precious breeding values for its special flowering period. This study surveyed the age structure and spatial distribution of C. azalea, analyzed its genetic diversity and fine-scale spatial genetic structure (SGS) using microsatellite markers for 629 individuals, and estimated the effect of human disturbances on its population dynamics. Results showed that this species had a relatively moderate genetic diversity (I = 0.989, He = 0.509, and Ho = 0.497), high rate of sapling (~ 35%), and a narrow habitat (~ 6 km long, ~ 10 m wide). Although the construction of dams and roads did not lead to a significant loss of genetic diversity and genetic differentiation (FST = 0.0096 ~ 0.0128, Nm = 19 ~ 26), it limited C. azalea’s seed flow (adults, 95 m; juveniles, 60 m), which was a reason for juveniles having a stronger SGS than adults. These results indicate that as an SPS, C. azalea still possesses the potential capacity for self-evolution and regeneration, however, it is at risk of extinction due to its small range, narrow habitat, and human distances. Furthermore, the results are also of enlightening significance to the conservation of other SPS, especially those distributed along the riparian zone.

How to increase the prestige of a scientist in the Russian Federation

The Russian science, according to the existing scientific resources, occupies leading places on many positions, demonstrates serious achievements in many fields, but low overall effectiveness. In the development of science, systemic problems are manifested due to numerous factors, the most important of which are considered in the work. The analysis of the modern development of science has revealed its main challenges. Special attention is paid to the problems of staffing the scientific and technical complex and identifying the causes of the decline in the scientist’s prestige. In Russia, the number of personnel employed in science has been constantly decreasing for many years. The number of postgraduates and doctoral students as well as the amount of dissertation defenses, has decreased 4–7 times over the past four years, and the age structure of the scientific staff has been deformed. The popularity of the scientist has decreased several times. Based on the analysis, the main factors of declining popularity are identified in the work: profession of the scientist is not prestigious; there is a low salary level; there are no mechanisms for popularising the profession; there is no qualitative assessment of the scientist’s work. Proposals for staffing scientific activities and increasing the prestige of the scientist’s work are formulated: increase of the cost of science; elimination of the problem of the scientific personnel’s aging; significant increase in the material support of the scientific personnel; expansion of the possibilities of using grant financing for basic research. Special attention is paid to solving the tasks of improving scientific activity, which are formulated in national projects.

Features of the application of the methodology of direct standardization in the comparative analysis of demographic indicators in the subjects of the Russian Federation

Aims — to conduct a comparative analysis of demographic indicators in the subjects of the Russian Federation using common and standardized coefficients on the example of mortality from the main causes. Methods. In this work, the method of direct standardization was applied using Rosstat data on the average annual population of the Russian Federation and data on the number of deaths from various causes for the period 1990-2021. The actual structure of the average annual population in the analysis was replaced by a standardized one calculated based on the European Standard of the population structure of 2013. Results. Since the European Standard for the Age Structure of the Population (ESP 2013) is currently the closest to the age structure of the population of the Russian Federation, it is recommended to use it when calculating standardized coefficients. Based on the example of assessing the mortality rates of the population in the context of the subjects of the Russian Federation, intensive indicators were initially calculated, which are presented in the form of a rating scale. When analyzing the rating of the subjects of the Russian Federation with the highest indicators of standardized mortality from all causes in 2022, the highest-ranking places were occupied by regions that previously showed "imaginary well-being" (when calculating total mortality), and a detailed assessment of which was not required. When calculating the indicators of general and standardized mortality of the population due to diseases of the circulatory system, followed by the compilation of ratings of subjects of the Russian Federation with the highest and lowest mortality rates, six subjects of the Russian Federation who were in the rating of subjects for the highest indicators of total mortality, after recalculation on standardized coefficients dropped out of it. A similar situation was observed when calculating the indicators of general and standardized mortality of the population from neoplasms, followed by the compilation of ratings of the subjects of the Russian Federation with the highest and lowest indicators. Conclusions. Thus, using the methodology of direct standardization at the federal level allows comparing the subjects of the Russian Federation with each other on several medical and demographic indicators.

Interspecific competition and survival pressures in endangered Barringtoniaracemosa populations of Mainland China

This study evaluates the growth, survival pressures, and community dynamics of Barringtonia racemosa (L.) Spreng. populations in Jiulong Mountain and Suixi County, Guangdong Province. Six distinct plant communities were identified, with human disturbances significantly disrupting natural succession processes. The population in Jiulong Mountain, particularly within the Talipariti tiliaceum-B. racemosa community (JLS-T), experienced higher survival pressures compared to Suixi County. Interspecific competition varied, with species like Derris trifoliata, T. tiliaceum, and invasives such as Ipomoea cairica and Mikania micrantha exerting substantial pressure on B. racemosa. Analysis of 234 B. racemosa individuals revealed significant correlations between diameter at breast height (DBH), plant height, and age structure distribution, with a linear relationship between DBH and height underscoring their relevance in understanding wood volume, biomass, and stand structure. Survival pressures were inversely related to DBH, indicating reduced competition as trees matured. Growth patterns exhibited an age-dependent plateau in height, potentially influenced by environmental and anthropogenic factors. Management strategies should prioritize the growth of individuals with DBH less than 5 cm (age classes I ~ II). These findings underscore the need for targeted conservation efforts to protect B. racemosa communities and sustain wetland ecosystems.

Maternal Mortality in the Context of the Aging Female Population in Moscow

Background. Maternal mortality is a key indicator characterizing the status of the healthcare system and the social well-being of the population. Most of the countries, especially developing countries, still face the problem of maternal mortality. Maternal age at birth is one of the main factors affecting maternal mortality. The studies show that women under 20 and over 35 are at high risk of pregnancy and delivery complications. During the past decades, the changes in social, economic, and cultural settings have resulted in an increase of the average maternal age in many countries, including Russia.Objective. To analyze maternal mortality in the context of the aging maternal age structure using the case of Moscow.Material and methods. The research used the official data from the Federal State Statistics Service of the Russian Federation (Rosstat).Results. The study investigated the correlation between changes in the age structure of women at birth and maternal mortality dynamics. The majority of maternal deaths is observed in women aged 30–40, especially in the 30-34 age group. The study confirmed the global trend towards an increasing age of first-time mothers. The aging of maternal age structure presents challenges for healthcare. The study results could be used to develop effective measures for reducing maternal mortality in the context of the aging maternal age structure.

How Aging and Low Fertility Influence Household Savings: A Case Study in China

This paper investigates the intricate relationship between demographic changes, particularly population aging and declining fertility, and household savings rates, with a specific emphasis on China. These demographic shifts carry significant consequences for economic growth and stability. As China's population ages, the growing demand for healthcare and pensions exerts pressure on household savings, while a declining fertility rate raises concerns about the future labor force and the sustainability of long-term savings. This paper reviews key theoretical frameworks such as the life-cycle hypothesis and precautionary savings theory, examining how shifts in population age structure influence consumption patterns, savings behavior, and overall economic resilience. Additionally, it delves into the broader socio-economic challenges posed by these demographic trends, including potential labor shortages and increased fiscal strain. By synthesizing a wide range of research, this review provides a comprehensive analysis of these demographic trends, offering insights for policymakers to promote sustainable household savings while ensuring balanced economic growth.

More twins expected in low-income countries with later maternal ages at birth and population growth.

How are the changing maternal age structure and population growth expected to shape future twinning rates in low-income countries? With maternal age at birth projected to shift toward older ages, twinning rates are also estimated to increase in most low-income countries by 2050 and even more by 2100. Many of the sub-Saharan African and South Asian countries are undergoing, and projected to further experience, the shift of maternal age at birth to older ages. Advanced maternal age is a well-established predictor of multiple births at the individual level, but currently, it is unknown how the changes in maternal age distribution are associated with the changes in twinning rates at the population level in low-income countries. We first estimated age-specific twinning probability based on Demographic Health Surveys and World Fertility Surveys data. We then scaled up the age-specific twinning probability at the population level to estimate changes in the number of twin births in 2050 and 2100 attributable to the estimated shifts in maternal age toward older ages as projected by the UN World Population Prospects (WPP). We analyzed ∼3.19 million births that occurred within 10 years before the interview. Majority of the births in our data took place between 1980 and 2015 across 39 countries, where the uptake of medically assisted reproduction (MAR) is known to have been low during the observation period. We estimated country fixed-effects models to obtain country-specific twinning rates and age-specific twinning probability. We applied these estimates to the future number of births projected by the UN WPP, to estimate the number of twin births in 2050 and 2100. With maternal age at birth projected to shift toward older ages, twinning rates are also estimated to increase in most countries by 2050 compared to 2010 (increases from 0.3% to 63% depending on countries), and even more in all studied countries by 2100 (increases from 3.5% to 79%). Due to its large population size, India will continue to have among the largest share of twin births despite its estimated decline of twin births by 10.5% by 2100. Nigeria, due to its not only large and growing population size but also high twinning rate, is expected to contribute the second largest number of twin births. Although the accuracy in maternal recall of multiple births tends to be high, our use of data based on recalled births from the past nonetheless imply a potential bias in our estimation of twinning rates. The present study suggests that, even if the spread of MAR remains slow in many low-income countries, twinning rates and number of twin births are expected to grow as an increase in maternal age at birth and population growth continue. Our findings call for more public health attention and societal support to be paid to twins and their families in low-income countries, given that twins are at higher risk of developmental challenges and health disadvantages. D.S.L. was supported by the European Union (ERC, BIOSFER, 101071773). K.J.B. was supported by a Pro Futura Scientia XIV Fellowship awarded by the Swedish Collegium for Advanced Study and Riksbankens Jubileumsfond. There are no competing interests to declare. N/A.