Natural Growth Rate Research Articles

Emission Saving Potentials of Freight Transportation in Europe: Shifting Road to Rail Transport?

This paper aims at investigating the savings potential of increasing the share of rail transport in the European freight transport sector regarding greenhouse gas emissions. This paper sets itself apart by using the realized modal shift instead of the potential as the starting point for calculating the associated potential reductions in GHG emissions. The expected emission reductions associated with shifting long-distance freight transport from road to rail until 2030, as considered in this paper, are estimated using the modal shift of EU-member states with the base year 2017 and national growth rates of rail share from 2005 to 2017. The expected emission reductions are relatively small compared to the total emissions of the growing freight transport sector although (very) ambitious scenarios were assumed. To achieve a substantial reduction in greenhouse gas emissions, transport initiatives must be complemented by a reduction in the specific emissions of the respective modes of transportation. The paper closes with a short outlook for the development of the transportation sector.

Disasters and Investment: Assessing the Performance of the Underlying Economy Following a Large-Scale Stimulus in the Built Environment

Disasters are often followed by a large-scale stimulus supporting the economy through the built environment, which can last years. During this time, official economic indicators tend to suggest the economy is doing well, but as activity winds down, the sentiment can quickly change. In response to the damaging 2011 earthquakes in Canterbury, New Zealand, the regional economy outpaced national economic growth rates for several years during the rebuild. The repair work on the built environment created years of elevated building activity. However, after the peak of the rebuilding activity, as economic and employment growth retracts below national growth, we are left with the question of how the underlying economy performs during large scale stimulus activity in the built environment. This paper assesses the performance of the underlying economy by quantifying the usual, demand-driven level of building activity at this time. Applying an Input–Output approach and excluding the economic benefit gained from the investment stimulus reveals the performance of the underlying economy. The results reveal a strong growing underlying economy, and while convergence was expected as the stimulus slowed down, the results found that growth had already crossed over for some time. The results reveal that the investment stimulus provides an initial 1.5% to 2% growth buffer from the underlying economy before the growth rates cross over. This supports short-term economic recovery and enables the underlying economy to transition away from a significant rebuild stimulus. Once the growth crosses over, five years after the disaster, economic growth in the underlying economy remains buoyant even if official regional economic data suggest otherwise.

National Governance Index, Corruption Index and Growth Rate—International Evidence from Sub-Saharan and MENA Countries

In an international setting of developing countries, applying advanced statistical estimation approaches such as the system generalized method of moments (GMM), two-stage least square (2SLS) regressions, and cluster analysis, this paper revisits the impact of macro-level governance quality and the corruption index on the economic growth rate. We use cross-country panel data for 40 sub-Saharan and the Middle Eastern and North African (MENA) countries over the period of 2009–2020. The empirical results document the positive and negative effects of the national governance index and the corruption index on the economic growth rate. Additionally, foreign direct investment and population have a positive impact on the economic growth rate and trade openness has a negative impact. The study evaluates the robustness of these associations through a series of tests. These findings have important policy implications for policymakers and regulators in developing countries. In particular, the study recommends the implementation of an anti-corruption campaign and improving country-level governance quality that could encourage increased foreign direct investment for an accelerated economic growth rate. These will further enhance accountability, transparency, the rule of law, social responsibility, the public voice, and government effectiveness.

The trend of services provided by human milk banks between 2010 and 2019 in Brazil

ObjectiveTo describe the trend of participation in group and individual support by human milk banks (HMBs) provided between 2010 and 2019 in Brazil. MethodsEcological study with data from participation in group and individual support provided by the HMBs between 2010 and 2019, available in the production report of the Brazilian Network of Human Milk Banks. The number of participation in group and individual support was expressed for Brazil and for Brazilian macroregions in absolute numbers. Trend analysis was performed from the analysis of index numbers, considering the year 2010 as a reference. It was calculated the ratio of the number of participation in group and individual support by HMBs for each macroregion and year. ResultsThere was an increase of 42% in participation in group support (300,595 in 2010 vs 425,570 in 2019) and an increase of 69% in individual support (1,157,038 in 2010 vs 1,962,162 in 2019). The North and Northeast macroregions had the highest growth rates in the provision of these services (122 and 131%, respectively), above the national growth rate in the study period. In contrast, the Midwest region showed a downward trend throughout this period, for both types of support. However, in the Midwest, there was a higher ratio of participation in groups by HMBs between 2010 and 2016 and for individual support by HMBs between 2010 and 2012. ConclusionIndividual and group support provided by the HMB as a strategy to support breastfeeding increased considerably in Brazil during the study period, especially in the North and Northeast regions.

THE MAIN DIRECTIONS AND CENTERS OF LABOR MIGRATION

This article discusses the main directions of labor migration. Demography in the world economy is a science that deals with the movement of population and labor resources, it studies the composition, dynamics of the population, as well as the general laws of location and migration, based on social, economic, biological and geographical factors. Based on this, population changes in different countries and regions, forecasts for the future are developed. In demographic statistics, indicators such as the birth rate (number of births per 1,000 people), the death rate (number of deaths per 1,000 people), the marriage rate, the natural growth rate, that is, the differences between births and deaths are widely used.

За изследването на възрастната генерация в България

Over the last few decades we have witnessed dynamic demographic changes around the world, in the European Union (EU) and in Bulgaria in particular. These are related to the decline in the population (depopulation) and its ageing (most often measured by the share of the population aged 65 and over in the total population), as well as migration. As early as the 1980s, the rate of natural population growth in Bulgaria began to decline, but for the first time in 1990 a negative natural growth rate was registered (-0.4‰), and in the following decades it was quite low - around -5‰. Today, Bulgaria is among the EU countries where these processes are most dynamic and even dramatic. As a result of the two factors (natural increase and migration), the population in Bulgaria is decreasing from nearly 9 million in 1988 to about 6.5 million in 2021.

Population Fitness of Eupeodes corollae Fabricius (Diptera: Syrphidae) Feeding on Different Species of Aphids.

Simple SummaryAs a candidate for controlling aphid populations, Eupeodes corollae Fabricius also performs a pollination function which is critical to agricultural systems. We evaluated the population life tables and flight performance of E. corollae fed on three prey species (Aphis craccivora Koch, Myzus persicae Sulzer and Megoura japonica Matsumura) to select suitable aphid species for keeping E. corollae indoors. The results showed that E. corollae completed development and reproduction on these three aphid species while achieving the shortest generation time, the maximum fecundity, and the highest intrinsic natural growth rate and flight ability on M. japonica. Our study indicated that M. japonica is the most suitable prey for E. corollae, providing a basis for utilizing the ecological service function of the hoverfly.Eupeodes corollae Fabricius, as one of the most common beneficial predatory insects in agricultural ecosystems, provides pollination and biological control services that help improve crop yield and maintain biodiversity. However, systematic research is needed on the species of aphids used for propagation. To develop highly fit populations of the important insect predator and crop pollinator, E. corollae, for research and commercial use, further research is needed to develop the most nutritious diet and efficient propagation methods. Here, the fitness of E. corollae was assessed in the laboratory after larvae were fed an aphid diet of Aphis craccivora Koch, Myzus persicae Sulzer or Megoura japonica Matsumura. The larval survival rate on M. japonica was significantly lower than on A. craccivora and M. persicae. The developmental duration for larvae (7.6 d) and pupae (6.9 d) was longest on A. craccivora. The pupal emergence rate on A. craccivora (98.0%) was significantly higher than on the other two, and lowest (64.7%) on M. japonica. On A. craccivora, M. persicae, and M. japonica, respectively, the generation time was 24.85 d, 23.12 d and 21.05 d; the value for the intrinsic rate of natural increase was 0.19, 0.20, and 0.21; and the value for the finite rate of increase was 1.21, 1.22, and 1.23. For flight variables, E. corollae attained the fastest velocity and longest distance and duration on M. japonica. The M. japonica diet, thus, provided the shortest generation time, the highest intrinsic rate of natural increase and finite rate of increase, the maximum fecundity and the greatest flight ability. Thus, to improve the survival rate of E. corollae larvae, A. craccivora or M. persicae can be used to feed newly hatched larvae, and M. japonica can be used for second- and third-instar larvae. These results provide a theoretical basis for feeding E. corollae and optimizing its ecosystem services.

Global stability of a delayed predator–prey system with fear and Holling-type II functional response in deterministic and stochastic environments

This paper is concerned with a delayed predator–prey system where besides direct predation, the prey species are affected by fear factor induced from predator species. The globally asymptotical stability of the coexisting equilibrium state in deterministic environment is studied. By perturbing the natural growth rates of prey species and predator species, the deterministic system is then extended to a stochastic version with white noise. We investigate the existence of stochastic positive solution and globally asymptotical stability of the equilibrium state. Our main results demonstrate that the fear and delay are harmless for the global stability of the equilibrium state in some cases, but sufficiently large white noise will destroy the stability. Some numerical examples are given to verify our analytical results.

Trajectory to local extinction of an isolated dugong population near Okinawa Island, Japan

A small animal population becomes extinct owing to demographic and environmental stochasticity after declining below the minimum viable population (MVP). However, the actual process of extinction derived by stochastic factors after crossing MVP has not been recorded for long-lived marine mammals. Here, we reconstructed the declining history of a small, isolated population of dugongs in Okinawa over 125 years. The initial population size of approximately 280–420 in the nineteenth century declined to approximately < 100 in 1917 because of overfishing, < 70 in 1979, 11 in 1997, 3 after 2006, and all known individuals disappeared or died by 2019. After 1979, a decline in the natural growth rate has led to extinction. Long-lived animals may persist for a few decades after the population falls below the MVP, at which time active conservation measures, such as captive breeding, should be implemented.

Spatial variations and social determinants of life expectancy in China, 2005–2020: A population-based spatial panel modelling study

SummaryBackgroundSocial determinants of health (SDOH) produce a broad range of life expectancy (LE) disparities. In China, limited literatures were found to report association between SDOH and LE at ecological level during a consecutive period of time from the spatial perspectives. This study aimed to determine the existence, quantify the magnitude, and interpret the association between SDOH and LE in China.MethodsProvincial-level LE were estimated from mortality records during 2005–2020 from National Mortality Surveillance System in China. A spatial panel Durbin model was used to investigate LE associated SDOH proxies. Spatial spillover effects were introduced to interpret direct and indirect effects caused by SDOH during long-term and short-term period on LE disparities.FindingsNationwide, LE increased from 73.1 (95% confidence interval (CI): 71.3, 74.4) years to 77.7 (95%CI: 76.5, 78.7) years from 2005 to 2020. Unequally spatial distribution of LE with High-High clustering in coastal areas and Low-Low clustering in western regions were observed. Locally, it was estimated that SDOH proxies statistically significant related to an increase of LE, including GDP (coefficient: 0.02, 95%CI: 0.00, 0.03), Gini index (coefficient: 2.35, 95%CI: 1.82, 2.88), number of beds in health care institutions (coefficient: 0.02, 95%CI: 0.00, 0.05) and natural growth rate of resident population (coefficient: 0.02, 95%CI: 0.01, 0.02). Direct and indirect effects decomposition during long-term and short-term of LE associated SDOH proxies demonstrated that GDP, urbanization rate, unemployment rate, education attainment, Gini index, number of beds in health care institutions, sex ratio, gross dependence ratio and natural growth rate of resident population not only affected local LE, but also exerted spatial spillover effects towards geographical neighbors.InterpretationSpatial variations of LE existed at provincial-level in China. SDOH regarding socioeconomic development and equity, healthcare resources, as well as population characteristics not only affected LE disparities at local scale but also among nearby provinces. Externalities of policy of those SDOH proxies should be took into consideration to promote health equity nationally. Comprehensive approaches on the basis of population strategy should be consolidated to optimize supportive socioeconomic environment and narrow the regional gap to reduce health disparities and increase LE.FundingNational Key Research & Development Program of China (Grant No.2018YFC1315301); Ministry of Education of China Humanities and Social Science General Program (Grant No.18YJC790138).

Assessment and key factors of urban liveability in underdeveloped regions: A case study of the Loess Plateau, China

Urban liveability is an important index to measure the sustainable development of urban socioeconomic. Based on the deconstruction of urban sustainable development goals (SDGs), a new-comprehensive and scientific evaluation index system was constructed to evaluate the urban liveability of underdeveloped regions, entropy weight TOPSIS model and Tobit model were used to investigate the urban liveability and key factors in underdeveloped regions. The evaluation index system was divided into seven aspects in this study, involving economic development, urban construction, public service, social progress, living standard, ecological environment, and resource utilization. To explore the key factors of urban liveability and the application of the index system in underdeveloped regions, the Loess Plateau was chosen for this investigation. The empirical results indicates that there are six significant key factors affecting urban liveability in the Loess Plateau. Among them, urbanization rate, natural population growth rate, and population density play a negative role in urban liveability. For another, per capita local fiscal revenue, per capita green area, and GDP growth rate play a positive role in urban liveability. The index system can evaluate the urban liveability scientifically of underdeveloped regions, it can be used for Livable city construction for other underdeveloped regions or developing countries.

A striking growth of CO2 emissions from the global cement industry driven by new facilities in emerging countries

Global industrialization and urbanization processes enabled a diverse cement production boom over the past three decades, as cement is the most important building construction material. Consequently, the cement industry is the second-largest industrial CO2 emitter (∼25% of global industrial CO2 emissions) globally. In this study, the Global Cement Emission Database, which encompasses anthropogenic CO2 emissions of individual production units worldwide for 1990–2019, was developed. A recently developed unit-level China Cement Emission Database was then applied to override China’s data and the combination of two databases is used to reveal the unit characteristics of CO2 emissions and ages for global cement plants, assess large disparities in national and regional CO2 emissions, growth rates and developmental stages from 1990–2019, and identify key emerging countries of carbon emissions and commitment. This study finds that globally, CO2 emissions from the cement industry have increased from 0.86 Gt in 1990 to 2.46 Gt in 2019 (increasing by 186%). More importantly, the large CO2 emissions and the striking growth rates from those emerging countries, including most of the developing countries in the Asia region and the Middle East and Africa region, are clearly identified. For example, the Middle East and Africa, including mostly developing or underdeveloped countries, only represented 0.07 Gt CO2 in 1990 (8.4% of the total), in contrast to 0.26 Gt (10.4% of the total) CO2 in 2019, which is a 4.5% average growth rate during 1990–2019. Further, the intensive expansion of large and new facilities since 2005 in Asia and the Middle East and Africa has resulted in heavy commitment (90.1% of global commitment in 2019), and mitigation threats in the future considering their increasing emissions (the national annual growth rate can be up to >80%) and growing infrastructure construction (∼50% of clinker capacity operating ⩽10 years). Our results highlight the cement industry’s development and young infrastructure in emerging economies; thus, future increasing cement demand and corresponding carbon commitment would pose great challenges to future decarbonization and climate change mitigation.

EFFECT OF INDOOR CONDITION OF BANGLADESH FACTORY TO WORKERS HEALTH AND BEHAVIOR

The economic growth of Bangladesh depends very much on the garments industries. In Bangladesh, the garments industries contribute directly to the economic growth at about 6 percent of national economic growth rate. A huge number of factories are developed and scattered around Bangladesh. Most of the factories are clustered around the capital city Dhaka and invite thousands of rural inhabitants in search of a job in the city and hoping to lead better life. Today, Bangladesh already confirmed her position as a world-leading clothing exporter. The total workers in these garment industries are around 3.6 million out of 150 million total population. These factories manufacture different types of readymade garments products and export those products to many different countries around the world. However, a good number of factories are not well designed in term of their indoor conditions and which have direct influence in terms of workers' health and wellbeing. The poor indoor conditions may directly affect the employees’ health where they can suffer from various illnesses over prolong durations. This study is aimed at finding out the indoor conditions that has the direct influence towards health and wellbeing of workers at the selected garment factories. For the purpose of this study,14 factories at 6 different locations were selected. A field study was held to assess workers' health and wellbeing while working at the selected garment factories in Bangladesh. During the field study, the questionnaire survey was conducted among the random sample of 405 workers. The workers answered and provided the information about their factory current indoor conditions. From the questionnaire, it is found working environment caused certain illnesses and affected the workers' behavior while they are working at factories. The findings of this research will help introduce measure and guideline to the factory owners so that they can take significant steps to upgrade their management system to improve and provide good indoor conditions for their workers and in term of business wise increase the production margin.

Innovation Research on Symbiotic Relationship of Organization’s Tacit Knowledge Transfer Network

The sustainable development of organizations is inseparable from innovation, and tacit knowledge is the core resource used to achieve organizational innovation. Due to the implicitness of tacit knowledge and the complexity of members’ relationships, symbiotic relationships between members have dramatically affected the transfer effect of tacit knowledge. However, previous studies on tacit knowledge transfer only focus on the characteristics of the subject or object; fewer consider the role of symbiotic relationships between knowledge subjects. An organization’s tacit knowledge transfer network (OTKTN) is a dynamic knowledge transfer network established among multiple members. Tacit knowledge transfer and sharing among network members conform to the symbiotic feature. To examine various relationships between members, and to investigate the mechanisms that impact tacit knowledge transfer, this article aims to analyze the symbiotic relationships in OTKTN based on the symbiotic perspective. The Lotka–Volterra model was used to construct symbiotic evolution model, and symbiotic coefficients were constructed from the four levels: knowledge-based psychological personal ownership (KPPO) of the knowledge provider, media richness, trust of the knowledge receiver, and organizational rewards matching, to discuss symbiotic modes. Finally, numerical simulation software was applied to simulate the evolution of knowledge levels in members. The results show that the four kinds of symbiotic modes between members include independence, commensalism, asymmetric mutualism, and symmetric mutualism. Symmetric mutualism is the best mode. In this mode, maximum level in independence mode affects the final stable knowledge level; the initial knowledge amount and natural growth rate both affect knowledge growth rate. Media richness, receiver’s trust, and organizational rewards matching can increase members’ tacit knowledge, but the knowledge provider’s KPPO inhibits members’ tacit knowledge growth. This article provides guidance to form a healthy symbiotic relationship and help organizations increase tacit knowledge.

Volumetric growth rates of untreated cavernous sinus meningiomas.

Meningiomas that arise primarily within the cavernous sinus are often believed to be more indolent in their growth pattern. Despite this perceived growth pattern, disabling symptoms can arise even with small tumors. While research has been done on cavernous sinus meningiomas (CSMs) and their treatment, very little is known about their natural growth rates. With a better understanding of the growth rate of CSM, patient treatment and guidance can be can optimized and individualized. The goal of this study was to determine volumetric growth rates of untreated CSMs. Thirty-seven patients with 166 MR images obtained between May 2004 and September 2019 were reviewed, with a range of 2-13 MR images per patient (average of 4.5 MR images per patient). These scans were obtained over an average follow-up period of 45.9 months (median 33.8, range 2.8-136.9 months). All imaging prior to any intervention was included in this analysis. Volumetric measurements were performed and assessed over time. The estimated volumetric growth rate was 23.3% per year (95% CI 10.2%-38.0%, p < 0.001), which is equivalent to an estimated volume doubling time (VDT) of 3.3 years (95% CI 2.1-7.1 years). There was no significant relationship between growth rate and patient age (p = 0.09) or between growth rate and patient sex (p = 0.78). The median absolute growth rate was 41% with a range of -1% to 1793%. With a definition of "growth" as an increase of greater than 20% during the observed period, 65% of tumors demonstrated growth within their observation interval. Growth rates for each tumor were calculated and tumors were segmented based on growth rate. Of 37 patients, 22% (8) demonstrated no growth (< 5% annual growth, equivalent to a VDT > 13.9 years), 32% (12) were designated as slow growth (annual growth rate 5%-20%, VDT 3.5-13.9 years), 38% (14) were found to have medium growth (annual growth rate 20%-100%, VDT 0.7-3.5 years), and 8% were considered fast growing (annual growth rate > 100%, VDT < 0.7 years). This study evaluated CSM volumetric growth rates. A deeper understanding of the natural history of untreated CSMs allows for better counseling and management of patients.

THE RESPONSE OF ECONOMIC GROWTH TO LIQUIDITY (AN EMPIRICAL STUDY ON PAPUA AND WEST PAPUA, INDONESIA)

This study aims to determine the response of regional economic growth to innovations on liquidity, saving-investment gap, trade openness, inflation and national growth rate. The basic approach of this study is constructed from the principles of open macroeconomy and financial intermediary system. This study used a quarterly data for the period of 2008 – 2019 and employed VAR/VECM/IRF/FEVD. The research novelty will be useful for the development of regional economics and for policy formulation in advancing the economy in the Papua region. Overall, this study found that the response of regional economic growth to innovation on liquidity, saving-investment gap, trade openness, inflation and national growth rate indicates a better synergy for Papua compared to West Papua. The result/novelty of this study is important as an input for the development of early warning system (EWS) and for reformulating the economic development policy and strategy, especially considering that the two provinces still have many underdeveloped districts.

A Comparative Study of the Fatty Acids and Monosaccharides of Wild and Cultivated Ulva sp.

There is a need to find new possible raw food sources with interesting nutritional values. One of the most unexploited sources are seaweeds. Thus, Ulva sp. is a green edible seaweed that shows a high growth rate in nature and can support drastic abiotic changes, such as temperature and salinity. This work aims to determine the main nutritional compounds, fatty acids (FAs) and monosaccharides profiles of Ulva sp. (collected from Mondego estuary, Portugal), to identify the potential of this seaweed as a food source. The present study also highlights the potential of controlled and semi-controlled cultivation systems in Ulva sp. profiles. The results showed that the controlled cultivation systems had higher essential FA and monosaccharide content than the semi-controlled cultivation systems. However, they are in some cases identical to wild individuals of Ulva sp., supporting that cultivation of Ulva sp. can be a key for food safety. It is crucial to control the associated risks of contamination that can occur in wild specimens.

INTERNATIONAL INTEGRATION PROCESSES INFLUENCE ON WELFARE OF COUNTRY

The primary objective of the research is to investigate the influence of international integration processes on national welfare. Peculiarities of trade and economic liberalization of trade through mechanism of regional trade agreements (RTA) forming have been scrutinized. Integration, which develops due to RTAs, is the most important mechanism of the international cooperation in the field of economic policy. This integration is a coordination and protection mechanism, which functions in a broad spectrum of policies. An exceptional role of RTAs in reaching country economic security has been estimated. RTAs being a result of a compromise reached by protectionism and anti-protectionism forces have been grounded. Using tools of the multiple regression model, the influence of integration processes, in which Ukraine and China participate, on national economic growth rates and on GDP per capita (as major parameters reflecting national welfare level) was simulated. This allowed detecting of the positive direct dependence between the trade liberalization and economic growth rates, as well as the inverse dependence between the trade liberalization and GDP per capita, for both countries. Based on these regression models, economic growth rates and GDP per capita were predicted for next years; according to this prediction, graduate increasing of national welfare shall occur in Ukraine and China.

Analysis ofFmsyin light of life‐history traits—Effects on its proxies and length‐based indicators

AbstractEquilibrium yields and biomasses in relation to fishing mortality were generated for a wide range of life‐history traits (LHTs), which included growth parameters, natural mortality, maturity, selectivity and steepness of the Beverton and Holt stock–recruitment relationship. For each combination of LHTs, the fishing mortality expected to produce maximum sustainable yield (Fmsy), its selected proxies (F0.1,F40%,F40%SSBandFmax) and mean length atFmsy(Lmsy) were estimated. Next, linear models combining the estimatedFmsyandLmsywith the traits were fitted (R2 &gt; .95). Almost all of the LHTs were statistically significant, and the largest effect onFmsywas from steepness, while natural mortality and growth rate had smaller effects. In the case ofLmsy, however, the largest effect in the fitted model was from the growth rate, while steepness influencedLmsyonly slightly. TheFmsyproxies were evaluated, andF40%SSBappeared to be a generally conservativeFmsyproxy, whileFmaxalways overestimatedFmsy, generally to a large extent.F0.1andF40%may be used asFmsyproxies or conservative proxies mainly for steepness values of 0.6 and higher; for lower steepness, they may markedly overestimateFmsy. The ratio of biomass atFmsyto virgin biomass was on average 0.34, and for a steepness of 0.9, some values were lower than 0.2. The analysis indicates that the use of the mean length of a catch in relation toLmsyfor evaluating stock status should be done with caution, especially for species with a high growth rate.

Natural history and growth rates of isolated common iliac artery aneurysms

ObjectiveThe natural history of isolated common iliac artery aneurysms (CIAAs) has not been well-studied. The optimal size threshold for elective repair of isolated CIAAs is also not well-defined. We sought to determine the natural history and growth rates of isolated CIAAs to justify a surveillance protocol and size for elective repair. MethodsIsolated CIAAs (>2 cm) identified from January 1, 2008, through February 29, 2020, at a single center were reviewed. Patient demographics, comorbidities, and details of CIAA operative repairs were retrospectively collected. All available duplex ultrasound and computed tomography scans were reviewed from time of CIAA identification through June 2020. ResultsThere were 244 isolated CIAAs found in 167 patients. The cohort was 94% male with an average age of 68.1 ± 8.8 years at the time of CIAA detection. CIAAs were identified with ultrasound examination 69% of the time with a mean CIAA diameter of 2.3 cm. Operative repair of a CIAA was performed in 11.4% of the cohort at an average diameter of 3.30 ± 1.02 cm. The majority of these repairs were performed via an endovascular approach (73.7%; n = 14). There were no symptomatic or ruptured isolated CIAAs. Concurrent aortic growth that led to an abdominal aortic aneurysm with diameter of at least 3 cm occurred in 10.6% (n = 26) of isolated CIAAs. The average length of time from CIAA diagnosis to repair was 65.7 ± 47.1 months. The overall CIAA growth rate was 0.4 mm/y. A subgroup analysis based on CIAA size demonstrated a growth rate of 0.2 mm/y fore CIAAs 2.00 to 2.49 cm, 0.3 mm/y for CIAAs 2.50 to 2.99cm, and 1.3 mm/y for CIAAs 3.0 cm or larger. There were two CIAAs greater than 3.0 cm with extreme growth, which significantly impacted the CIAA growth rate on sensitivity analysis. After excluding those two CIAAs from the model, the overall CIAA growth rate was 0.3 mm/y. The subgroup analysis then demonstrated a growth rate of 0.2 mm/y for CIAAs 2.00 to 2.49cm, 0.3 mm/y for CIAAs 2.50 to 2.99cm, and 0.5 mm/y for CIAAs 3 cm or larger. ConclusionsIsolated CIAAs are typically slow growing aneurysms that expectedly grow faster as they enlarge. Given the rare occurrence of rapid isolated CIAA growth, we recommend surveillance at 3 years for 2.00 to 2.49 cm isolated CIAAs, 2 years for 2.50 to 2.99 cm isolated CIAAs, and yearly for isolated CIAAs greater than 3.0 cm. The lack of symptomatic or ruptured isolated CIAAs in this study supports delaying elective repair until an isolated CIAA diameter reaches at least 3.5 cm. These recommendations should be considered for isolated CIAA practice guidelines.