Distribution Of Ages Research Articles

The effect of the LPA gene on aortic valve calcification in a Portuguese population

Abstract Introduction Aortic valve calcium (AVC) deposition is one of the mechanisms behind aortic sclerosis and stenosis. There is a known association between LPA gene rs3798220 T>C polymorphism and the development of severe aortic stenosis. However, it is still unknown if it has been a driving factor since the early stages of the disease. Objective Investigate, in our population, the association between the LPA gene variant rs3798220 T>C and aortic valve calcification. Methods AVC was measured in 451 consecutive individuals from the prospective arm of the GENEMACOR study with a mean age of 63.4±9.7 years, 58.8% male. AVC score was performed by cardiac computed tomography and reported as Agatston units. Results were separated into two groups (Group A: AVC=0; Group B: AVC>0). Lp(a) levels were analyzed in the different groups. Each individual was genotyped for LPA rs3798220 T>C. This variant has a minor allele frequency (MAF)<2%; hence, the risk homozygous CC is a rare genotype, and we used the heterozygous CT in our analysis. The bivariate and multivariate logistic regression analysis evaluated the presence of AVC adjusting to traditional risk factors (TRFs) and the LPA heterozygous genotype (CT). Results LP(a) levels were higher in the CT allele versus the homozygous TT, but this difference did not reach a statistical significance. After multivariate analysis, the heterozygous LPA rs3798220 T>C polymorphism remained an independent risk factor for the presence of aortic valve calcification (OR=12.14, p=0.002) together with age (OR=1.13, p<0.0001), arterial hypertension (AHT) (OR=1.96, p=0.006) and alcohol consumption (OR=2.46, p=0.016). Conclusion The LPA gene variant rs3798220 T>C is associated with the presence of aortic valve calcification in a Portuguese population. In such an age-dependent disease as aortic stenosis, the inversion in the age pyramid will see a dramatic increase in the prevalence of aortic stenosis. The early identification of high-risk individuals might enable prompt traditional risk factors control and disease prevention. Larger population studies may help to determine if this difference is driven by Lp(a) levels.

Comparison of hospital treatments of the Roma settlements’ inhabitants in Slovenia

Abstract Background Roma ethnic minority in Slovenia was recognized as a vulnerable group with worse health indicators and significantly shorter life expectancy. The vast majority of Roma population in Slovenia have health insurance. We were investigating the use of hospital services in Roma population according to their age and comparing it with the rest of the population. Methods We determined the inhabitants of Roma settlements from the Slovenian register on residents. The data on hospital treatments used were from Slovenian national register on hospital treatments for the period 2018 to 2022. We compared different ratios according to certain hospital treatments within age categories of patients and co-pared those two groups. The frequency statistics, ANOVA and comparison of column proportion tests were used (p-value<0.005, 95% CI). Results Inhabitants of Roma settlements were more often treating in hospitals that rest of population. If comparing the frequency of hospital treatments between age groups only in Roma population, the percentage of hospital treatments steeply declines with age as well as the number of persons in age groups. The highest percentages and numbers of services are in the youngest age group of 0-15 years, and the lowest in the oldest group (75+). Therefore, significantly higher ratios of hospital treatments were detected in younger then in older age groups. Conclusions Roma children and youngsters (0-15 years old) had the highest rate of hospital treatments and it declined with the age. It was consistent with age pyramid of Roma as young population as well as emphasized care for children in culture. The steady decline rate of hospital treatments with age could be explain with delayed seeking of health care services in adult age and higher premature mortality that leads to smaller adult population. Additional and in-depth research is necessary to explain the root causes of higher premature mortality and use of primary and preventive health services. Key messages • Higher use of hospital treatments was caused by higher morbidity. It is necessary to explore the leading causes of hospital treatments and premature mortality. • It is necessary to explore the use of primary health care service, preventive service and level of health literacy of inhabitants of Roma settlements.

Age structure of carp and catfish catch as a tool to assess ecological health of fished stocks from the Ganga River system with special reference to Mahseer Tor tor (Hamilton, 1822)

In the 20th centuary, the economically important carp species Labeo rohita, Tor tor, & Labeo calbasu and the catfishes Rita rita & Bagarius bagarius contributed substantially to the total fish catch from the Ganga River system in India. Samples were recorded between December 2003 and June 2004 from fish landing centers in the Ken, Paisuni, and Tons rivers for L. rohita, T. tor and L. calbasu. Rita rita and B. bagarius were sampled between September 2001 and September 2003 in the Ganga River system. The data were used to evaluate the growth and age structures of fish populations. Age classes varied 0+–5+ for L. rohita in the Ken & Paisuni rivers and 0+–8+ in the Tons River. For T. tor, the age classes varied 1+–6+ in the Ken & Paisuni rivers and 1+–8+ in the Tons. Age classes of L. calbasu varied 1+–6+ in the Ken River, 1+–5+ in the Paisuni River, and 1+–7+ in the Tons. In the Ganga River, age classes of R. rita & B. bagarius varied 0+–7+ and 0+–6+, respectively. The L. rohita, age pyramid showed a tendency for bell shape in Ken River, base tends to be broader through bell shape in Paisuni River, and bell-shaped age pyramid was slightly distorted in Tons River. In case of T. tor, tendency for bell shape in Ken River and bell-shaped age pyramid in Paisun River & Tons River were obtained. In case of L. calbasu, heavy bottom shaped age pyramid was recorded in Ken and Paisuni rivers, while base tends to be broader in the Tons River. Bell shaped age pyramid was recorded for B. bagarius in the Ganga River while heavy bottom shape for R. rita in the Ganga River. Overall, T. tor is facing heavy fishing pressure and also targeted fish species by fishermen from the Ganga River system.

Different copula types and reliability applications for a new fisk probability model

In this research endeavor, the authors introduce a novel lifetime probability model. This distribution is meticulously examined and characterized, offering insights into its behavior and applicability in various contexts. The proposed new density function of this distribution has various heavy tail forms that are useful in the field of reliability, insurance and statistical modeling. This allows for the representation and modeling of a wide range of data sets that are diverse in their form and nature. The new distribution is characterized by having different patterns of risk or failure rates. The researchers extend the new distribution to the bivariate domain through different methods, including the Morgenstern-Farley-Gumbel distribution, the modified Morgenstern-Farley-Gumbel distribution, the famous Clayton mathematical versions, and the Rennie versions. These extensions enhance the usefulness of the proposed distribution in modeling multivariate age and reliability data and dependencies between variables. The study presents some statistical modeling experiments on reliability data and some important comparisons are presented within the framework of some statistical comparison criteria.

Towards the construction of regional marine radiocarbon calibration curves: an unsupervised machine learning approach

Abstract. Radiocarbon may serve as a powerful dating tool in palaeoceanography, but its accuracy is limited by the need to calibrate radiocarbon dates to calendar ages. A key problem is that marine radiocarbon dates must be corrected for past offsets from either the contemporary atmosphere (i.e. “reservoir age” offsets) or a modelled estimate of the global average surface ocean (i.e. delta-R offsets). This presents a challenge because the spatial distribution of reservoir ages and delta-R offsets can vary significantly, particularly over periods of major marine hydrographic and/or carbon cycle change such as the last deglaciation. Modern reservoir age and delta-R estimates therefore have limited applicability. While forward modelling of past R-age variability has been proposed as a means of resolving this problem, this requires accurate a priori knowledge of past global radiocarbon budget closure (i.e. production, and cycling), which we currently lack. In this context, the construction of empirical regional marine calibration curves could provide a way forward. However, the spatial reach of such calibrations and their robustness subject to (uncertain) temporal changes in climate and ocean circulation would need to be tested. Here, we use unsupervised machine learning techniques to define distinct regions of the surface ocean that exhibit coherent behaviour in terms of their radiocarbon age offsets from the contemporary atmosphere (R ages), regardless of the causes of R-age variability. We apply multiple algorithms (k-means, k-medoids, and hierarchical clustering) to outputs from two different numerical models spanning a range of climate states, forcings, and timescales of adjustment. Comparisons between the cluster assignments across model runs confirm some robust regional patterns that likely stem from constraints imposed by large-scale ocean and atmospheric physics. At the coarsest scale, regions of coherent R-age variability correspond to the major ocean basins. By further dividing basin-scale shape-based clusters into amplitude-based subclusters, we recover regional associations, such as increased high-latitude R ages, or the propagation of R-age anomalies from regions of deep mixing in the Southern Ocean to upwelling sites in the eastern equatorial Pacific, which cohere with known modern oceanographic processes. We show that the medoids (i.e. the most representative locations) for these regional sub-clusters provide significantly better approximations of simulated local R-age variability than constant offsets from the global surface average. This remains true when cluster assignments obtained from one model simulation are applied to simulated R-age time series from another. Further, model-based clusters are found to be broadly consistent with existing reservoir age reconstructions that span the last ∼30 kyr. We therefore propose that machine learning provides a promising approach to the problem of defining regions for which empirical marine radiocarbon calibration curves may eventually be generated.

Financial impact of pandemics on pension sustainability: an application for Spain

AbstractEpidemiologists are warning that the next pandemic is almost around the corner. As we have seen during the COVID-19 pandemic, the death toll was at the highest for over 60th, transforming the population pyramids. In times of pandemics, two effects on sustainability of the pay-as-you-go (PAYG) pension scheme go in different directions: the increase in old-age mortality (leading to a decrease in pension spending) and the increase in unemployment (leading to a decline in income from contributions). In this paper, we investigate the long-term effects of pandemics on the financial sustainability of PAYG pension schemes, taking into account changes in both mortality and unemployment factors. Using functional data analysis we develop projections of population pyramids and allow for anticipated mortality jumps as a result of future pandemics. An application is carried out using mortality and fertility data from Spain. Given some plausible assumptions, our findings indicate, firstly, that the financial sustainability of the Spanish pension system is compromised. Secondly, in the event of a pandemic, we observe that financial sustainability is primarily driven by the mortality effect—resulting in a decrease in pension expenditure—while the impact of unemployment is almost negligible.

Analysis of Population Change of the 0-14 Year Age Group in Türkiye (2000-2022)

Age groups with wide and narrow ranges provide the opportunity to make detailed evaluations for planning studies in demographic analyses. Particularly, population pyramids are prepared using age group data by sex. In the bottom three rows of the pyramids, 0-4, 5-9, and 10-14 age group data can be used to evaluate population growth and fertility rates. In addition, age groups provide an indication of the amount of dependent and active population in a society, thus facilitating future population forecasts. Broad age ranges categorize the 0-14 age group as the young dependant population, the 15-64 age group as the active population, and the 65+ age group as the elderly dependent population. The proportional change of these age groups in certain date intervals and the reasons for which age groups are in an upward or downward trend also give an idea about the general welfare levels of countries. The current population's demographic trends guide the planning of employment, education, health, and many other socio-economic investments. Population policies are based on the proportional distribution of age groups and population projections. In this study, the change in the population of the 0-14 age group in Türkiye has been analyzed according to the Classification of Territorial Units for Statistics Level-1 (İBBS Düzey-1) since 2000. The population amount, population density, age, and gender structure of this age group are emphasized. In the research, State Institute of Statistics (DIE) 2000 General Population Census and TURKSTAT (TÜİK) Regional statistics data for 2022 were utilized. In 2000, since the Classification of Territorial Units for Statistics had not yet been established, province-based data from 2000 were evaluated and new data were created at the “İBBS Düzey-1” (CUTS Level-1) scale in order to ensure integrity in tables and graphs.

Uncertainty quantification in epigenetic clocks via conformalized quantile regression.

DNA methylation (DNAm) is a chemical modification of DNA that can be influenced by various factors, including age, environment, and lifestyle. An epigenetic clock is a predictive tool that measures biological age based on DNAm levels. It can provide insights into an individual's biological age, which may differ from their chronological age. This difference, known as the epigenetic age acceleration, may indicate the state of one's health and risk for age-related diseases. Moreover, epigenetic clocks are used in studies of aging to assess the effectiveness of anti-aging interventions and to understand the underlying mechanisms of aging and disease. Various epigenetic clocks have been developed using samples from different populations, tissues, and cell types, typically by training high-dimensional linear regression models with an elastic net penalty. While these models can predict mean biological age with high precision, there is a lack of uncertainty quantification which is important for interpreting the precision of age estimations and for clinical decision-making. To understand the distribution of a biological age clock beyond its mean, we propose a general pipeline for training epigenetic clocks, based on an integration of high-dimensional quantile regression and conformal prediction, to effectively reveal population heterogeneity and construct prediction intervals. Our approach produces adaptive prediction intervals not only achieving nominal coverage but also accounting for the inherent variability across individuals. By using the data collected from 728 blood samples in 11 DNAm datasets from children, we find that our quantile regression-based prediction intervals are narrower than those derived from conventional mean regression-based epigenetic clocks. This observation demonstrates an improved statistical efficiency over the existing pipeline for training epigenetic clocks. In addition, the resulting intervals have a synchronized varying pattern to age acceleration, effectively revealing cellular evolutionary heterogeneity in age patterns in different developmental stages during individual childhoods and adolescent cohort. Our findings suggest that conformalized high-dimensional quantile regression can produce valid prediction intervals and uncover underlying population heterogeneity. Although our methodology focuses on the distribution of aging in children, it is applicable to a broader range of populations to improve understanding of epigenetic age beyond the mean. This inference-based toolbox could provide valuable insights for future applications of epigenetic interventions for age-related diseases.

Effects of intravenous Tranexamic Acid on bleeding during burn surgery: a double-blinded randomized clinical trial

Blood loss during burn surgeries significantly contributes to morbidity and mortality. Tranexamic Acid (TXA), an antifibrinolytic agent, is hypothesized to reduce intraoperative bleeding. This double-blinded, randomized clinical trial aimed to assess the efficacy of systemic TXA in severe burn patients (total body surface area [TBSA] >20%) undergoing surgery. The study evaluated the impact of TXA on surgical bleeding, operating room (OR) time, intravenous (IV) fluid requirements, length of hospital stay (LOS), and overall patient outcomes. A total of 94 patients, with equal distribution in age, sex, and TBSA, were randomly assigned into two groups (47 each). We administered TXA as a 10mg/kg loading dose followed by a 1mg/kg/h infusion during surgery. Results demonstrated significant reductions in blood loss (P-value: 0.043), total IV fluid volume (P-value: 0.021), OR time (P-value: 0.002), LOS (P-value: 0.0001), and transfusion necessity (P-value: 0.024) in the TXA group. Notably, women and patients without inhalation injuries exhibited better responses to TXA treatment, and graft survival was lower in the TXA group. The study concludes that IV TXA administration during burn surgeries can effectively reduce bleeding, minimize IV fluid and blood transfusion needs, and shorten surgery duration, enhancing overall surgical outcomes.

Detrital zircon U-Pb ages and provenance of Paleogene paleochannel strata, Sierra Nevada and western Nevada: Implications for paleotopographic evolution

The Paleogene paleotopography of the western United States, which may grant insight into Farallon subduction dynamics and North American Cordillera orogenic processes, can be constrained by reconstructing drainage networks through sediment provenance studies. In the northern Sierra Nevada, the provenance of SW-directed, Paleogene paleochannel deposits is controversial; prior studies favor either sources proximal to the deposits or distal source areas in central Nevada. These different hypothesized source areas would have contrasting implications for the paleotopography of the Sierra Nevada and western Basin and Range. We conducted a new provenance analysis of paleochannel deposits in the Sierra Nevada and western Nevada using new and compiled detrital zircon U-Pb age data from across the preserved paleochannel network, together with compiled bedrock geochronologic ages of potential sediment source areas for the paleochannel deposits. The geochro­nology compilation of potential source areas reveals systematic longitudinal variations in bedrock ages within the study area. Jurassic ages are present primarily in the western Sierra Nevada batholith, Cretaceous ages are dominant in the eastern Sierra Nevada batholith, and Eocene ages are present only in north-central Nevada. The distribution of potential source ages allows confident inference of sediment provenance from detrital zircon U-Pb ages. The distributions of detrital zircon U-Pb ages in the paleochannel depos­its can be categorized into three distinct types. The first type, found in the vicinity of Malakoff Diggins State Historic Park (SHP) and further northwest, is dominated by Jurassic, Paleozoic, and Precambrian ages reflecting derivation from local sources in the western Sierra Nevada, and also contains scattered Eocene ages. The lack of Late Cretaceous ages in these samples, despite the presence of Late Cretaceous plutons in close proximity to the east, suggests small sediment source areas with fluvial transport of zircon grains no farther than 50 km. The few Eocene ages in these samples likely reflect volcanic air fall, consistent with an overlying tuff at one sample site that is interpreted to have its volcanic source to the north, outside the paleochannel network. The second zircon age distribution type, from samples south of Malakoff Diggins SHP, includes Cretaceous and Jurassic ages representative of exposed bedrock across the entire width of the Sierra Nevada batholith but no Eocene ages. This combination of ages suggests a sediment source area that encompassed the entire batholith but did not include north-central Nevada. The third zircon age distribution type, from samples to the northeast of Malakoff Diggins SHP, contains Jurassic, Cretaceous, and Eocene ages consistent with fluvial derivation of sediment from the entire width of the Sierran batholith as well as from north-central Nevada. This third type only occurs in fluvial deposits interbedded with Oligocene ignimbrite tuffs, whereas samples older than the Oligocene tuffs belong to zircon age distribution types 1 or 2. Thus, prior to the emplacement of Oligocene ignimbrites, there is no evidence of fluvial transport of sand-sized sediment from north-central Nevada sources to Sierran paleochannel deposits. The lack of pre-Oligocene fluvial transport across the Sierra Nevada may reflect either a Paleogene drainage divide that separated the Sierra Nevada from north-central Nevada or a large-scale knick zone with a low-gradient upstream reach that trapped sand and larger sediment. The first arrival of fluvially transported Eocene zircon grains following Oligocene ignimbrite emplacement suggests that ignimbrite volcanism, and related hinterland uplift, established or promoted sediment transport from north-central Nevada across the Sierra Nevada by driving drainage reorganization or steepening existing channels. Our provenance analysis broadly confirms previous paleochannel network reconstructions, especially for the Ancestral Yuba River, and thus validates the use of paleochannel deposits as a datum by which to infer post-Paleogene tilting of the northern Sierra Nevada. Azimuthal trends in Ancestral Yuba River paleochannel gradient suggest ~0.6° SW-directed, post-Paleogene tilting of the northern Sierra Nevada, which would have resulted in ~1 km of uplift of the range crest. Such a magnitude is consistent with Eocene–Oligocene stable isotope paleoelevation estimates.

Probing the strength of radial migration via churning by using metal-rich red giant stars from APOGEE

ABSTRACT Making use of the APOGEE DR17 catalogue with high quality data for 143 509 red giant branch stars we explore the strength of different mechanisms that causes a star to radially migrate in the Milky Way stellar disc. At any position in the disc we find stars that are more metal-rich than the local interstellar medium. This is surprising and normally attributed to the migration of these stars after their formation inside their current Galactocentric radius. Such stars are prime candidates for studying the strength of different migratory processes. We specifically select two types of metal-rich stars: (i) super metal-rich stars ($\mathrm{[Fe/H]}\gt 0.2$) and (ii) stars that are more metal-rich than their local environment. For both, we explore the distribution of orbital parameters and ages as evidence of their migration history. We find that most super metal-rich stars have experienced some amount of churning as they have orbits with $R_g\gtrsim 5 \,{\rm kpc}$. Furthermore, about half of the super metal-rich stars are on non-circular orbits ($\mathrm{ecc} \gt 0.15$) and therefore also have experienced blurring. The metallicity of young stars in our sample is generally the same as the metallicity of the interstellar medium, suggesting they have not radially migrated yet. Stars with lower metallicity than the local environment have intermediate to old ages. We further find that super metal-rich stars have approximately the same age distribution at all Galactocentric radii, which suggests that radial migration is a key mechanism responsible for the chemical compositions of stellar populations in the Milky Way.

Relationship Between Gut Microbiota and Pancreatitis: A Systematic Review

Background and Aims: The human gastrointestinal system hosts a rich and diverse microbial community, surpassing a staggering 10[ 14 ] bacteria, collectively harbouring more than 5,000,000 genes. The aim of this study is to carry out a systematic review of human studies in order to investigate the correlation between the gut microbiota and pancreatic disorders. Materials and Methods: To systematically compile relevant research between 2011 and 2022, a thorough exploration of the MEDLINE and EMBASE databases was executed. The initial search results, encompassing all identified studies, were meticulously scrutinised, including a comprehensive review of their reference lists to ensure the completeness of our search. Initially, our search strategy yielded a total of 114 items. Subsequent refinement involved the removal of 58 duplicate articles identified in both searches. Following a meticulous screening process involving title, abstract and keyword assessments, 36 studies progressed to the next phase of evaluation. However, this cohort underwent further scrutiny, leading to the exclusion of 11 studies categorised as reviews or case reports, 5 in languages other than English that have been published and 20 that did not investigate the microbiome. As a result, a focused set of 20 papers emerged for in-depth evaluation for eligibility. Results: The demographic profile of the patients revealed that nearly half were men, with an average age of 52 years (interquartile range of 44-56). The interquartile range further ranged from 45% to 52%, reflecting the distribution of ages within the group. Among the studies scrutinising acute pancreatitis, gallstones emerged as the predominant cause in 9 out of 15, while 7 studies focusing on chronic pancreatitis found no evidence of gallstones. Conclusion: This comprehensive, systematic investigation has furnished robust evidence substantiating the intricate connection between pancreatitis and the microbiota.

Comparative analysis of nutritional status among institutionalised and community-dwelling elderly women and its association with mental health status and cognitive function.

Population pyramids are significantly impacted by the global phenomena of ageing. It has been reported that depression and cognitive function have an impact on the nutritional status of older adults. Depression is the most common psychiatric problem in old age, and cognitive deterioration is frequently observed in this age group. This descriptive and comparative study set out to compare the cognitive abilities, nutritional health and depression status of older adults who lived in community settings and in assisted living facilities. A total of 250 older women (125 from institutionalised old age home and 125 from community) participated in a cross-sectional study (residing at Rajarhat, Newtown area). The lengthy version of the Mini Nutritional Assessment tool (MNA®) was used to evaluate the participants' nutritional status. The Geriatric Depression Scale (GDS 30) was used to evaluate the severity of the depression. Using the Folstein Mini-Mental State Examination (MMSE), cognitive function was assessed. Using SPSS software, the Chi-square, Kruskal-Wallis test, and Spearman's rho correlation coefficient were computed. In the present study, it was observed that only 30.4% of the respondents who are community-dwelling elderly had normal MNA score, whereas 69.6% were at risk of malnutrition or already malnourished. Considering institutionalised elderly it was observed that only 7.2% were normal and 92.8% were malnourished/at risk of malnutrition. Statistically significant association was observed between nutritional status and mental health status (P = 0.00) as well as cognitive function (P = 0.00) among old age home residing elderly. Among the community-dwelling elderly mental health status has significant association with their nutritional status (P = 0.00) and cognitive function (P = 0.00) as well. Community-dwelling elderly were relatively healthy compared to old age home residents. Maintaining the nutritional, cognitive, and mental health of institutionalised and community-dwelling elderly women requires the implementation of physical and cognitive stimulation activities as well as interventions targeted at improving a healthy diet.

Planning natural gas supply chain pathways for energy system decarbonisation: An Australian case study

The future role of natural gas systems in a deeply decarbonised world is very uncertain. This work seeks to characterise the changes that the clean energy transition is likely to induce in the natural gas chain, across extraction and transmission, distribution networks and gas consumption/use trends, for various scenarios with different demand and supply drivers. First, the results of a least-cost macro-scale energy system planning optimisation are explored to identify future natural gas demand and supply requirements. Second, those findings are used as inputs to a detailed analysis of the full gas supply chain, from extraction to final use, to examine the evolution of i) stored resource levels; ii) transmission and distribution networks operation and financing; and iii) required capacity and siting of gas generation; all, with a realistic account of the related infrastructure. Australia is investigated as a case study that relies on natural gas for both domestic and export purposes. Results project a shift towards a more localised gas consumption to be largely supplied by fewer basins, with associated potential transmission and extraction bottlenecks. They anticipate an overall less utilised, ageing distribution network with potential challenges to asset reliability and financing. Finally, they demonstrate both the scheduled and early retirement of fossil generation assets can allow the siting of considerable amounts of new gas power firming capacity on brownfield sites, thus offering an opportunity to reduce total system costs.

Exploring the Evolution of a Dwarf Spheroidal Galaxy with Smoothed-particle Hydrodynamics Simulations. I. Stellar Feedback

A fundamental question regarding the evolution of dwarf spheroidal galaxies is the identification of the key physical mechanisms responsible for gas depletion. Here, we focus on the study of stellar feedback in isolated dwarf spheroidal galaxies by performing numerical simulations using a modified version of the smoothed-particle hydrodynamics code GADGET-3. The Milky Way satellite Leo II (PGC 34176) in the Local Group was considered as our default model dwarf galaxy. The parameter space for the stellar feedback models was explored to match observational constraints of Leo II, such as residual gas mass, total mass within the tidal radius, star formation history, final stellar mass, stellar ages, and metallicity. Additionally, we examined the impact of the binary fraction of stars, initial mass function, dark matter halo mass, and initial gas reservoir. Many simulations revealed recent star formation quenching due to stellar feedback. In general, the gas depletion, expected star formation history, total mass of stars, and total mass within the tidal radius were adequately reproduced in the simulations when compared to observational estimates. However, there were discrepancies in the distribution of stellar ages and metallicities, which suggested that the cosmic gas infall would play a more complex role in our dwarf spheroidal galaxy than captured by a monolithic infall scenario. Our results suggest that currently quenched dwarf galaxies may not necessarily need to evolve within clusters or groups and that stellar feedback alone could be a sufficient factor in shaping at least some of these galaxies as we observe them today.

Proyeksi Penduduk Terhadap Kondisi Ketenagakerjaan Di Kota Kupang Dalam Menghadapi Bonus Demografi Tahun 2025 – 2030

This study aims to project the number and pyramid of population and employment conditions of Kupang City in facing the demographic bonus in 2025-2030. Population projection is done using the spectrum application and employment conditions are seen based on the availability and absorption of labor. The results showed that there was an increase in population in Kupang during 2025-2030 with a stationary population pyramid. The demographic bonus experienced by Kupang City has an impact on existing labor conditions, namely the availability of a potential workforce. However, unemployment remains a concern for the Kupang government. The existing business sectors in Kupang City in 2025-2030 are not able to keep up with the availability of labor, leading to high unemployment in 2025-2030.

Population of Russia: demographic situation, problems and prospects

Analysis of the size, structure and age-sex composition of the population of Russia is the most important task of modern statistics, providing government agencies with the necessary information for developing programs and plans for the development of key sectors of the economy. In times of economic downturns and recessions, it is important for authorities to have reliable and complete information about the state of the population, since it is the population size and its structure that are the basis of human resources for the development of sectors of the economy, including agriculture, which ensures food security and preservation of the population, decides strategic development tasks for the country as a whole. The study is aimed at analyzing the state and identifying patterns of changes in the Russian population, population distribution, identifying trends in the dynamics of the working-age and elderly population, and analyzing the gender and age pyramid of Russia for 2023. To conduct a comprehensive study, the following methods were used: calculation of demographic coefficients, alignment of time series. The results of the study made it possible to propose directions for improving measures within the framework of the existing demographic policy of the state to ensure uniform distribution of the population throughout the country, reduce the tax burden on individuals, and increase labor productivity.

Circulation Timescales and Pathways of Atlantic Water in the Canada Basin: Insights From Transient Tracers 129I and 236U

AbstractAnthropogenic radionuclides 129I and 236U are used to investigate pathways of the Atlantic Water flow in the Canada Basin, estimate transport timescales, and investigate mixing dynamics within the Atlantic Water layer and the overlying Pacific Water. Transit Time Distribution (TTD) model mean ages indicate water takes 25–35 years to reach the Canada Basin from the entrance of the Arctic, with limited lateral and vertical mixing along the core of the Arctic Ocean Boundary Current. Mode ages obtained from the model yield shorter transport times of 20–32 years. These age estimates agree with previous studies using these radionuclides and ventilation tracers in this region, indicating a steady‐state flow of Atlantic Water for the last 15 years. The distribution of the isotopes in the Atlantic layer indicates two pathways Atlantic Water may take into the basin, supported by the distribution of ages in the TTD model. End‐member mixing models indicate that the Pacific Winter water acquires a 20%–40% Atlantic Water signal of the radionuclides, upwelled over short periods, most likely along the shelf and Barrow Canyon region.

A new detection method for the ageing state of composite insulators based on spectral–spatial feature fusion

Composite insulators are integral to the power grid, providing electrical insulation and mechanical support. However, their prolonged exposure to outdoor conditions renders them vulnerable to ageing. This can result in flashovers and economic losses. Hyperspectral imaging (HSI) has been identified as a promising non-contact detection method to effectively assess the microscopic ageing status of these insulators’ surfaces. This study involved conducting artificial accelerated ageing experiments to mimic extended outdoor operational conditions. The static contact angle of ageing silicone rubber samples served as the basis for ageing classification. High-resolution HSIs of samples at various ageing stages were obtained, covering wavelengths from 400 nm to 1040 nm. Singular spectrum analysis was applied to denoise spectral and spatial domains, eliminating environmental and equipment-related noise effectively. Additionally, a convolutional neural network (CNN) was utilised to extract deep features from the spectral domain and combine them with spatial domain features, thus reducing dimensionality. The resulting fused spatial–spectral features were classified using a support vector machine. The joint denoising and feature fusion in this study’s spectral–spatial domain resulted in a notable improvement of 34.9 % in overall accuracy, achieving a score of 98.3 %. This approach exhibited superior performance, particularly in evaluating severely aged samples. The proposed approach enhances the accuracy in assessing the ageing status of composite insulators and enables pixel-level visualisation of ageing distribution. This assists in guiding the design of insulators’ shapes and materials for various environmental conditions. Moreover, this method is potentially applicable in detecting ageing in other electrical equipment.

Water quality deterioration modeling in aged distribution mains: A case study in Addis Ababa, Ethiopia

Water quality deterioration modeling in aged distribution mains: A case study in Addis Ababa, Ethiopia