demographic effect
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Author(s):  
Husham Abdelrahman ◽  
Hassan Al-Thani ◽  
Naushad Ahmad Khan ◽  
Monira Mollazehi ◽  
Mohammad Asim ◽  
...  

Background: The trauma incidence follows specific patterns in different societies and is expected to increase over the weekend and nighttime. We aimed to explore and analyze the incidence, pattern, and severity of trauma at different times (working hours vs. out off-working hours, weekdays vs. weekends and season). Methods: A retrospective analysis was conducted at a level 1 trauma facility in Qatar. All injured patients admitted between June 2017 and May 2018 were included. The data were analyzed to determine whether outcomes and care parameters of these patients differed between regular working hours and off-working hours, weekdays vs. weekends, and between season intervals. Results: During the study period, 2477 patients were admitted. A total of 816 (32.9%) patients presented during working hours and 1500 (60.6%) during off-working hours. Off-working hours presentations differed significantly with the injury severity score (ISS) (p  <  0.001), ICU length of stay (p  =  0.001), blood transfusions (p = 0.001), intubations (p = 0.001), mortality rate (9.7% vs. 0.7%; p < 0.001), and disposition to rehabilitation centers. Weekend presentations were significantly associated with a higher ISS (p = 0.01), Priority 1 trauma activation (19.1% vs. 14.7%; p = 0005), and need for intubation (21% vs. 16%; p = 0.002). The length of stay (ICU and hospital), mortality, and disposition to rehabilitation centers and other clinical parameters did not show any significant differences. No significant seasonal variation was observed in terms of admissions at the trauma center. Conclusions: The off-working hours admission showed an apparent demographic effect in involved mechanisms, injury severity, and trauma activations, while outcomes, especially the mortality rate, were significantly different during nights but not during the weekends. The only observed seasonal effect was a decrease in the number of admissions during the summer break.


2021 ◽  
Vol 14 (5) ◽  
pp. 2575-2601
Author(s):  
Leonardo Calle ◽  
Benjamin Poulter

Abstract. Forest ecosystem processes follow classic responses with age, peaking production around canopy closure and declining thereafter. Although age dynamics might be more dominant in certain regions over others, demographic effects on net primary production (NPP) and heterotrophic respiration (Rh) are bound to exist. Yet, explicit representation of ecosystem demography is notably absent in many global ecosystem models. This is concerning because the global community relies on these models to regularly update our collective understanding of the global carbon cycle. This paper aims to present the technical developments of a computationally efficient approach for representing age-class dynamics within a global ecosystem model, the Lund–Potsdam–Jena – Wald, Schnee, Landschaft version 2.0 (LPJ-wsl v2.0) dynamic global vegetation model and to determine if explicit representation of demography influenced ecosystem stocks and fluxes at global scales or at the level of a grid cell. The modeled age classes are initially created by simulated fire and prescribed wood harvesting or abandonment of managed land, otherwise aging naturally until an additional disturbance is simulated or prescribed. In this paper, we show that the age module can capture classic demographic patterns in stem density and tree height compared to inventory data, and that simulated patterns of ecosystem function follow classic responses with age. We also present two scientific applications of the model to assess the modeled age-class distribution over time and to determine the demographic effect on ecosystem fluxes relative to climate. Simulations show that, between 1860 and 2016, zonal age distribution on Earth was driven predominately by fire, causing a 45- to 60-year difference in ages between older boreal (50–90∘ N) and younger tropical (23∘ S–23∘ N) ecosystems. Between simulation years 1860 and 2016, land-use change and land management were responsible for a decrease in zonal age by −6 years in boreal and by −21 years in both temperate (23–50∘ N) and tropical latitudes, with the anthropogenic effect on zonal age distribution increasing over time. A statistical model helped to reduce LPJ-wsl v2.0 complexity by predicting per-grid-cell annual NPP and Rh fluxes by three terms: precipitation, temperature, and age class; at global scales, R2 was between 0.95 and 0.98. As determined by the statistical model, the demographic effect on ecosystem function was often less than 0.10 kg C m−2 yr−1 but as high as 0.60 kg C m−2 yr−1 where the effect was greatest. In the eastern forests of North America, the simulated demographic effect was of similar magnitude, or greater than, the effects of climate; simulated demographic effects were similarly important in large regions of every vegetated continent. Simulated spatial datasets are provided for global ecosystem ages and the estimated coefficients for effects of precipitation, temperature and demography on ecosystem function. The discussion focuses on our finding of an increasing role of demography in the global carbon cycle, the effect of demography on relaxation times (resilience) following a disturbance event and its implications at global scales, and a finding of a 40 Pg C increase in biomass turnover when including age dynamics at global scales. Whereas time is the only mechanism that increases ecosystem age, any additional disturbance not explicitly modeled will decrease age. The LPJ-wsl v2.0 age module represents another step forward towards understanding the role of demography in global ecosystems.


2021 ◽  
Author(s):  
Marcia C. Castro ◽  
Susie Gurzenda ◽  
Cassio M. Turra ◽  
Sun Kim ◽  
Theresa Andrasfay ◽  
...  

Brazil has the second-largest number of COVID-19 deaths worldwide. We use data on reported deaths to measure and compare the death toll across states from a demographic perspective. We estimate a decline in 2020 life expectancy at birth of 1.94 years, resulting in a mortality level not seen since 2013. The reduction in life expectancy at age 65 was 1.58 years, setting Brazil back to 2009 levels. The decline was larger for males, widening by 2.3% and 5.4% the female-male gap in life expectancy at birth and at age 65, respectively. Among states, Amazonas lost 59.6% of the improvements in life expectancy at birth since 2000. With 2021 COVID-19 deaths at about 43% of the total 2020 figures (as of mid-March) the demographic effect is likely to be even higher this year.


2021 ◽  
Vol 7 (3) ◽  
pp. 192
Author(s):  
Laura Garzoli ◽  
Elena Bozzetta ◽  
Katia Varello ◽  
Andrea Cappelleri ◽  
Elena Patriarca ◽  
...  

Although no mass mortality has been recorded so far, the precise demographic effect of white-nose syndrome (WNS) on European bats still remains to be ascertained. Following the first isolation of P. destructans in Italy, further surveys were performed to assess the distribution of the fungus in NW Italy and its effects on bats. Data were collected from March 2019 to April 2020 at sites used for hibernation (six sites) and/or for reproduction (four sites) in Piedmont and Aosta Valley. A total of 138 bats, belonging to 10 species, were examined to identify clinical features possibly related to the fungal presence. Culture from swabs and the molecular identification of isolates confirmed the presence of P. destructans in bats from five sites, including two maternal roosts. Dermal fungal infiltration, the criterion to assess the presence of WNS, was observed in biopsies of bats belonging to Myotis blythii, M. daubentonii, M. emarginatus and M. myotis. This is the first report of the disease in Italy. The results suggest a greater susceptibility to the infection of the genus Myotis and particularly of M. emarginatus, possibly due to the long length of its hibernation period. Other fungal dermatophytes were also observed.


2020 ◽  
Author(s):  
Leonardo Calle ◽  
Benjamin Poulter

Abstract. Forest ecosystem processes follow classic responses with age, peaking production around canopy closure and declin-ing thereafter. Although age dynamics might be more dominant in certain regions over others, demographic effects on net primary production (NPP) and heterotrophic respiration (Rh) are bound to exist. Yet, explicit representation of ecosystem demography is notably absent in most global ecosystem models. This is concerning because the glob-al community relies on these models to regularly update our collective understanding of the global carbon cycle. This paper aims to fill this gap in understanding by presenting the technical developments of a computationally-efficient approach for representing age-class dynamics within a global ecosystem model, the LPJ-wsl v2.0 Dynamic Global Vegetation Model. The modeled age-classes are initially created by fire feedbacks, wood harvesting, and abandonment of managed land, otherwise aging naturally until a stand-clearing disturbance is simulated or pre-scribed. In this paper, we show that the age-module can capture classic demographic patterns in stem density and tree height compared to inventory data, and that patterns of ecosystem function follow classic responses with age. We also present a few scientific applications of the model to assess the modeled age-class distribution over time and to determine the demographic effect on ecosystem fluxes relative to climate. Simulations show that, between 1860 and 2016, zonal age distribution on Earth was driven predominately by fire, causing a ~ 45-year difference in ages between boreal (50N–90N) and tropical (23S–23N) latitudes. Land use change and land management was responsible for an additional decrease in zonal age by −6 years in boreal and by −21 years in temperate (23N–50N) and tropical latitudes, with the anthropogenic effect on zonal age distribution increasing over time. A statistical model helped reduced LPJ-wsl complexity by predicting per-grid-cell annual NPP and Rh fluxes by three terms: precipitation, temperature and age-class; at global scales, R2 was between 0.95 and 0.98. As determined by the statistical model, the demographic effect on ecosystem function was often less than 0.10 kg C m−2 yr−1 but as high as 0.60 kg C m−2 yr−1 where the effect was greatest. In eastern forests of North America, the demographic effect was of similar magni-tude, or greater than, the effects of climate; demographic effects were similarly important in large regions of every vegetated continent. Spatial datasets are provided for global ecosystem ages and the estimated coefficients for effects of precipitation, temperature and demography on ecosystem function. The discussion focuses on our finding of an increasing role of demography in the global carbon cycle, the effect of demography on relaxation times (resilience) following a disturbance event and its implications at global scales, and a finding of a 40-Pg C increase in turnover from age dynamics at global scales. Whereas time is the only mechanism that increases ecosystem age, any addi-tional disturbance not explicitly modeled will decrease age. This LPJ-based age-module therefore simulates the up-per limit of age-class distributions on Earth and represents another step forward towards understanding the role of demography in global ecosystems.


2020 ◽  
Vol 11 (5) ◽  
pp. 334
Author(s):  
Adnan Abdelkarim Thiabat ◽  
Taghreed Musleh Kattoua

Jordan is affected by an increase in the ratio of public debt to a percentage of GDP. The increase rate has reached 85.8% (Jordan’s central bank in numbers). And this is a serious indicator that affects the economic conditions and living standards. The study dealt with the final private consumption and the factors affecting it. The first factor is the gross domestic product (GDP), and it is a reverse view of influence, consumption is one of the components of GDP through spending, which is influential and influenced by it, the second factor was the demographic effect, and the study took the number of workers as part of the demographic factor and the third factor is the level of prices. The study took the rate of inflation. In cases of inflation and high prices, the state resorted to reducing public spending and increasing taxes to reduce actual demand (Hardan, Tahir 1997).The study was from 2006 to 2016 as a sufficient period for measurement and the availability of accurate data. The study found that there is a relationship between the first and second variable and denied the relationship to the third variable, due to price fluctuations in the study period and one of the most important recommendations was to replace local labor with foreign labor.


2019 ◽  
Vol 286 (1916) ◽  
pp. 20192230 ◽  
Author(s):  
H. N. Abernathy ◽  
D. A. Crawford ◽  
E. P. Garrison ◽  
R. B. Chandler ◽  
M. L. Conner ◽  
...  

Extreme climatic events (ECEs) are increasing in frequency and intensity and this necessitates understanding their influence on organisms. Animal behaviour may mitigate the effects of ECEs, but field studies are rare because ECEs are infrequent and unpredictable. Hurricane Irma made landfall in southwestern Florida where we were monitoring white-tailed deer ( Odocoileus virginianus seminolus ) with GPS collars. We report on an opportunistic case study of behavioural responses exhibited by a large mammal during an ECE, mitigation strategies for reducing the severity of the ECE effects, and the demographic effect of the ECE based on known-fate of individual animals. Deer altered resource selection by selecting higher elevation pine and hardwood forests and avoiding marshes. Most deer left their home ranges during Hurricane Irma, and the probability of leaving was inversely related to home range area. Movement rates increased the day of the storm, and no mortality was attributed to Hurricane Irma. We suggest deer mobility and refuge habitat allowed deer to behaviourally mitigate the negative effects of the storm, and ultimately, aid in survival. Our work contributes to the small but growing body of literature linking behavioural responses exhibited during ECEs to survival, which cumulatively will provide insight for predictions of a species resilience to ECEs and improve our understanding of how behavioural traits offset the negative impacts of global climate change.


2019 ◽  
Vol 76 (1) ◽  
pp. 168-184 ◽  
Author(s):  
Rachel D. Neuenhoff ◽  
Douglas P. Swain ◽  
Sean P. Cox ◽  
Murdoch K. McAllister ◽  
Andrew W. Trites ◽  
...  

Most stocks of Atlantic cod (Gadus morhua) in the Northwest Atlantic collapsed in the early 1990s, with little sign of recovery since then. In the southern Gulf of St. Lawrence (sGSL), the failed recovery is due to severe increases in the natural mortality of adult Atlantic cod. We examined the role of predation by grey seals (Halichoerus grypus) in this failed recovery by directly incorporating grey seal predation in the population model for Atlantic cod via a functional response. Estimated predation mortality of adult Atlantic cod increased sharply during the cod collapse and has continued to increase, comprising the majority of mortality since the late 1990s. While predation by grey seals appeared to play a minor role in the collapse of Atlantic cod, we found it to be the main factor preventing recovery. Our results are consistent with the hypothesis that failed recovery is due to predation-driven Allee effects, a demographic effect due to the decline in cod abundance and an emergent effect resulting from increasing grey seal abundance. Under current conditions, extirpation of sGSL Atlantic cod appears likely unless there is a large decline in the abundance of grey seals.


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