scholarly journals Growth acceleration results in faster telomere shortening later in life

2021 ◽  
Vol 288 (1956) ◽  
pp. 20211118
Author(s):  
Pablo Salmón ◽  
Caroline Millet ◽  
Colin Selman ◽  
Pat Monaghan
Keyword(s):  
Growth Rate ◽  
Blood Cells ◽  
Later Life ◽  
Experimental Period ◽  
Growth Trajectory ◽  
Telomere Shortening ◽  
Time Period ◽  
Accelerated Growth ◽  
Telomere Dynamics

There is a wealth of evidence for a lifespan penalty when environmental conditions influence an individual's growth trajectory, such that growth rate is accelerated to attain a target size within a limited time period. Given this empirically demonstrated relationship between accelerated growth and lifespan, and the links between lifespan and telomere dynamics, increased telomere loss could underpin this growth–lifespan trade. We experimentally modified the growth trajectory of nestling zebra finches ( Taeniopygia guttata ), inducing a group of nestlings to accelerate their growth between 7 and 15 days of age, the main phase of body growth. We then sequentially measured their telomere length in red blood cells at various time points from 7 days to full adulthood (120 days). Accelerated growth between 7 and 15 days was not associated with a detectable increase in telomere shortening during this period compared with controls. However, only in the treatment group induced to show growth acceleration was the rate of growth during the experimental period positively related to the amount of telomere shortening between 15 and 120 days. Our findings provide evidence of a long-term influence of growth rate on later-life telomere shortening, but only when individuals have accelerated growth in response to environmental circumstances.

ON THE CONSUMPTION/DISTRIBUTION THEOREM UNDER THE LONG-RUN GROWTH CRITERION SUBJECT TO A DRAWDOWN CONSTRAINT

2010 ◽  
Vol 13 (06) ◽  
pp. 931-957 ◽  
Author(s):  
MICHAEL J. KLASS ◽  
KRZYSZTOF NOWICKI
Keyword(s):  
Growth Rate ◽  
Short Term ◽  
Long Run ◽  
Time Period ◽  
Total Capital ◽  
Growth Criterion ◽  
Drawdown Constraint ◽  
Riskless Asset ◽  
Distribution Theorem

Consider any discrete time sequence of investment fortunes Fn which has a finite long-run growth rate [Formula: see text] when subject to the present value capital drawdown constraint Fne-rn ≥ λ* max 0≤k≤nFke-rk, where 0 ≤ λ* < 1, in the presence of a riskless asset affording a return of er dollars per time period per dollar invested. We show that money can be withdrawn for consumption from the invested capital without either reducing the long-run growth rate of such capital or violating the drawdown constraint for our capital sequence, while simultaneously increasing the amount of capital withdrawn for consumption at the identical long-term rate of V(r, λ*). We extend this result to an exponentially increasing number of consumption categories and discuss how additional yearly contributions can temporarily augment the total capital under management. In addition, we assess the short-term practicality of creating such an endowment/consumption/distribution program.

The Effects of Reduced Salinity on the Shell Growth of Small Mytilus Edulis

1984 ◽  
Vol 64 (1) ◽  
pp. 171-182 ◽  
Author(s):  
Patricia C. Almada-Villela
Keyword(s):  
Growth Rate ◽  
Mytilus Edulis ◽  
High Salinity ◽  
Shell Growth ◽  
Experimental Period ◽  
Gradual Decline ◽  
Poor Growth ◽  
Term Response ◽  
Better Than

The shell growth of small coastal Mytilus edulis L. was measured at three different constant low salinities over short periods of time. Growth was significantly depressed in 6·4 and 16‰ S but not in 22·4‰ S. Fluctuating salinities between 0 and 32‰ S depressed growth whether the fluctuations were of sinusoidal or abrupt form. After 1 week of preconditioning to constant 32‰ S the growth of coastal (Bangor) mussels was better than estuarine (Conwy) mussels. However, after two weeks’ preconditioning to 32‰ S the estuarine mussels displayed the best growth. In the fluctuating regime, both coastal and estuarine mussels exhibited poor growth rates. The long-term response of the shell growth of coastal M. edulis was followed over a period of 44 days. Salinities in the range 1·8–9·6‰ S were lethal to the mussels within 10 days. In 12·8 and 16‰ S growth was initially delayed but recovered eventually. There was a gradual decline in the growth rate of the mussels exposed to the higher salinities (19·2–32‰) and an improvement in the growth of the mussels living in lower salinities (12·8 and 16‰) to levels nearly matching that of the high salinity animals by day 37. This suggests that acclimation of the shell growth of M. edulis to salinities in the 12·8–28·8‰ S range was achieved by the mussels during the experimental period.

scholarly journals Can we explain the observed methane variability after the Mount Pinatubo eruption?

2015 ◽  
Vol 15 (13) ◽  
pp. 19111-19160
Author(s):  
N. Bândă ◽  
M. Krol ◽  
M. van Weele ◽  
T. van Noije ◽  
P. Le Sager ◽  
...  
Keyword(s):  
Growth Rate ◽  
Biomass Burning ◽  
Partial Recovery ◽  
Mount Pinatubo ◽  
Sources And Sinks ◽  
Time Period ◽  
Pinatubo Eruption ◽  
Emission Changes

Abstract. The CH4 growth rate in the atmosphere showed large variations after the Pinatubo eruption in June 1991. A decrease of more than 10 ppb yr-1 in the growth rate over the course of 1992 was reported and a partial recovery in the following year. Although several reasons have been proposed to explain the evolution of CH4 after the eruption, their contributions to the observed variations are not yet resolved. CH4 is removed from the atmosphere by the reaction with tropospheric OH, which in turn is produced by O3 photolysis under UV radiation. The CH4 removal after the Pinatubo eruption might have been affected by changes in tropospheric UV levels due to the presence of stratospheric SO2 and sulfate aerosols, and due to enhanced ozone depletion on Pinatubo aerosols. The perturbed climate after the eruption also altered both sources and sinks of atmospheric CH4. Furthermore, CH4 concentrations were influenced by other factors of natural variability in that period, such as ENSO and biomass burning events. Emissions of CO, NOX and NMVOCs also affected CH4 concentrations indirectly by influencing tropospheric OH levels. Potential drivers of CH4 variability are investigated using the TM5 global chemistry model. The contribution that each driver had to the global CH4 variability during the period 1990 to 1995 is quantified. We find that a decrease of 8–10 ppb yr-1 CH4 is explained by a combination of the above processes. However, the timing of the minimum growth rate is found 6–9 months later than observed. The long-term decrease in CH4 growth rate over the period 1990 to 1995 is well captured and can be attributed to an increase in OH concentrations over this time period. Potential uncertainties in our modelled CH4 growth rate include emissions of CH4 from wetlands, biomass burning emissions of CH4 and other compounds, biogenic NMVOC and the sensitivity of OH to NMVOC emission changes. Two inventories are used for CH4 emissions from wetlands, ORCHIDEE and LPJ, to investigate the role of uncertainties in these emissions. Although the higher climate sensitivity of ORCHIDEE improves the simulated CH4 growth rate change after Pinatubo, none of the two inventories properly captures the observed CH4 variability in this period.

scholarly journals Socioeconomic disparities and infancy growth trajectory: a population-based and longitudinal study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Zi-yu Shao ◽  
Peng Wang ◽  
Pei Li ◽  
Yu Sun ◽  
Pei-pei Li ◽  
...  
Keyword(s):  
Growth Rate ◽  
Longitudinal Study ◽  
Birth Weight ◽  
Low Birth Weight ◽  
Rapid Growth ◽  
Growth Mixture Modeling ◽  
Growth Trajectory ◽  
Delivery Mode ◽  
Low Ses ◽  
Accelerated Growth

Abstract Background The association of low socioeconomic status (SES) with childhood and adolescent obesity has been reported. It is unknown whether low SES affects body mass index (BMI) growth trajectory in the first 12 mo of life. Moreover, accelerated growth as a compensatory mechanism for low birth weight (LBW) during infancy, is an important predictor of later obesity. The aim of the present study was to examine the association of low SES with infancy BMI growth rate and trajectory for LBW and normal birth weight (NBW) infants. Methods From September 2012 to October 2014, a total of 387 infants in this longitudinal study was subjected to repeated measures of weight and length from birth to 12 mo in Hefei. Generalized growth mixture modeling was used to classify the infancy BMI growth trajectories. Differences in infancy BMI z score (zBMI) and BMI growth rate between low SES and high SES were estimated based on linear regression after adjusting for several confounders including maternal age, pregnancy BMI, physical activity during pregnancy, paternal BMI as well as alcohol use, paternal smoking status, breastfeeding duration and delivery mode. Results Infancy BMI trajectories in this study were classified into three categories: rapid growth (class 1), normal growth (class 2) and slow growth (class 3). Low SES infants had the higher zBMI than high SES infants for LBW group at age 6 mo [zBMI difference with 95% CI at 6 mo: 0.28(0.03, 0.53); at 12 mo: 0.21(0.01, 0.43)]. Low SES infants had more rapid zBMI growth rate than those with high SES for low birth weight between 0 and 6 months. Controlling for the confounders, these associations remained robust. We found the lower SES in the rapid growth group. Conclusions These findings highlighted the impact of low SES on increasing BMI and accelerated growth during early infancy. Health care and relatively optimal family environment in the first 12 mo of life, especially for LBW infants, are benefit to shape the better infancy growth trajectory.

Physical Activity and Skeletal Health in Adolescents

1994 ◽  
Vol 6 (4) ◽  
pp. 330-347 ◽  
Author(s):  
Donald A. Bailey ◽  
Alan D. Martin
Keyword(s):  
Physical Activity ◽  
Later Life ◽  
Optimal Level ◽  
Long Term Effects ◽  
Mineral Density ◽  
Skeletal Health ◽  
Time Period ◽  
Intense Activity ◽  
Relationship Of

A considerable amount of research into osteoporosis has focused on the management and treatment of bone loss in later life. More recently, a limited amount of research has been directed toward the development of an optimal level of peak bone mass during the adolescent and early adult years. While genetics is a major determinant of bone status, there is considerable evidence that physical activity is an important nonhereditary factor. Studies on adults suggest that the positive effect of physical activity on bone is modest in the short term but may be quite powerful with more intense activity that overloads the muscular system for a longer time period. In children, however, our knowledge about the long-term effects of physical activity on bone accretion is incomplete. This paper presents a review of the pediatric literature dealing with the relationship of physical activity to bone mineral density status in the adolescent population.

scholarly journals Can we explain the observed methane variability after the Mount Pinatubo eruption?

2016 ◽  
Vol 16 (1) ◽  
pp. 195-214 ◽  
Author(s):  
N. Bândă ◽  
M. Krol ◽  
M. van Weele ◽  
T. van Noije ◽  
P. Le Sager ◽  
...  
Keyword(s):  
Growth Rate ◽  
Biomass Burning ◽  
Southern Oscillation ◽  
Partial Recovery ◽  
Sources And Sinks ◽  
Time Period ◽  
Pinatubo Eruption ◽  
Emission Changes

Abstract. The CH4 growth rate in the atmosphere showed large variations after the Pinatubo eruption in June 1991. A decrease of more than 10 ppb yr−1 in the growth rate over the course of 1992 was reported, and a partial recovery in the following year. Although several reasons have been proposed to explain the evolution of CH4 after the eruption, their contributions to the observed variations are not yet resolved. CH4 is removed from the atmosphere by the reaction with tropospheric OH, which in turn is produced by O3 photolysis under UV radiation. The CH4 removal after the Pinatubo eruption might have been affected by changes in tropospheric UV levels due to the presence of stratospheric SO2 and sulfate aerosols, and due to enhanced ozone depletion on Pinatubo aerosols. The perturbed climate after the eruption also altered both sources and sinks of atmospheric CH4. Furthermore, CH4 concentrations were influenced by other factors of natural variability in that period, such as El Niño–Southern Oscillation (ENSO) and biomass burning events. Emissions of CO, NOX and non-methane volatile organic compounds (NMVOCs) also affected CH4 concentrations indirectly by influencing tropospheric OH levels.Potential drivers of CH4 variability are investigated using the TM5 global chemistry model. The contribution that each driver had to the global CH4 variability during the period 1990 to 1995 is quantified. We find that a decrease of 8–10 ppb yr−1 CH4 is explained by a combination of the above processes. However, the timing of the minimum growth rate is found 6&amp;nash;9 months later than observed. The long-term decrease in CH4 growth rate over the period 1990 to 1995 is well captured and can be attributed to an increase in OH concentrations over this time period. Potential uncertainties in our modelled CH4 growth rate include emissions of CH4 from wetlands, biomass burning emissions of CH4 and other compounds, biogenic NMVOC and the sensitivity of OH to NMVOC emission changes. Two inventories are used for CH4 emissions from wetlands, ORCHIDEE and LPJ, to investigate the role of uncertainties in these emissions. Although the higher climate sensitivity of ORCHIDEE improves the simulated CH4 growth rate change after Pinatubo, none of the two inventories properly captures the observed CH4 variability in this period.

Placental restriction of fetal growth reduces size at birth and alters postnatal growth, feeding activity, and adiposity in the young lamb

2007 ◽  
Vol 292 (2) ◽  
pp. R875-R886 ◽  
Author(s):  
Miles J. De Blasio ◽  
Kathryn L. Gatford ◽  
Jeffrey S. Robinson ◽  
Julie A. Owens
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Feeding Activity ◽  
Later Life ◽  
Postnatal Growth ◽  
Postnatal Life ◽  
Absolute Growth ◽  
Accelerated Growth ◽  
Early Postnatal Life ◽  
Size At Birth

Intrauterine growth restriction (IUGR) is associated with accelerated growth after birth. Together, IUGR and accelerated growth after birth predict reduced lean tissue mass and increased obesity in later life. Although placental insufficiency is a major cause of IUGR, whether it alters growth and adiposity in early postnatal life is not known. We hypothesized that placental restriction (PR) in the sheep would reduce size at birth and increase postnatal growth rate, fat mass, and feeding activity in the young lamb. PR reduced survival rate and size at birth, with soft tissues reduced to a greater extent than skeletal tissues and relative sparing of head width ( P < 0.05 for all). PR did not alter absolute growth rates (i.e., the slope of the line of best fit for age vs. parameter size from birth to 45 days of age) but increased neonatal fractional growth rates (absolute growth rate relative to size at birth) for body weight (+24%), tibia (+15%) and metatarsal (+18%) lengths, hindlimb (+23%) and abdominal (+19%) circumferences, and fractional growth rates for current weight ( P < 0.05) weekly throughout the first 45 days of life. PR and small size at birth reduced individual skeletal muscle weights and increased visceral adiposity in absolute and relative terms. PR also altered feeding activity, which increased with decreasing size at birth and was predictive of increased postnatal growth and adiposity. In conclusion, PR reduced size at birth and induced catch-up growth postnatally, normalizing weight and length but increasing adiposity in early postnatal life. Increased feeding activity may contribute to these alterations in growth and body composition following prenatal restraint and, if they persist, may lead to adverse metabolic and cardiovascular outcomes in later life.

scholarly journals Effect of salinity changes on growth, survival and biochemical parameters of freshwater fish Gibelion catla (Hamilton, 1822)

2021 ◽  
Vol 42 (6) ◽  
pp. 1519-1525
Author(s):  
S.K. Ahirwal ◽  
◽  
P.C. Das ◽  
K. Sarma ◽  
T. Kumar ◽  
...  
Keyword(s):  
Growth Rate ◽  
Blood Cells ◽  
Biochemical Parameters ◽  
White Blood Cells ◽  
Haemoglobin Concentration ◽  
Experimental Period ◽  
Quality Parameters ◽  
Control Fish ◽  
Feed Conversion ◽  
Nitrite Nitrate

Aim: The present investigation was conducted to access the effect of salinity stress on growth performance, survival and biochemical parameters of Gibelion catla under different salinity conditions with an idea to assess the potentiality of this species in inland saline affected areas. Methodology: A 30-day-experiment was conducted in 1000 l (n=10) FRP tanks to study the effect of different salinity levels on the growth and biochemical parameters of catla species. A total of 120 fish (10.4 g) was randomly distributed into four treatments (0, 3, 6 and 9 ppt) with three replicates. The water quality parameters such as pH, temperature, nitrite, nitrate, ammonia, alkalinity and dissolved oxygen were recorded for each treatment on weekly basis, whereas fish sampling was carried out at 0th and 30th day of the experimental period to ascertain survival, weight gain, specific growth rate and feed conversion ratio of the fishes from each treatment. Results: The highest growth rate was found in control subsequently in 3 and 6 ppt and the survival rate was 96.67, 83.33, 76.67 and 0% against 0, 3, 6 and 9 ppt, respectively. The red blood cells (3.65×106 μl) and haemoglobin concentration, (8.17 gm dl-1) were also higher in control fish, followed by 3 and 6 ppt. However, white blood cells (24.40×106 μl) and glucose level (123.23 mg dl-1) were higher at 6 ppt, compared to control. Plasma protein level of fish at control (0 ppt salinity) was significantly higher than those of fish exposed to 3 and 6 ppt salinities. Interpretation: The present investigation revealed that an increase in salinity level had a significant impact on the growth and physiology of Gibelion catla. However, this species can be reared in low saline areas for some time which will not only help in the utilization of salt affected areas but will also help in the generation of employment and income.

How to secure external sustainability of the russian economy

2013 ◽  
pp. 4-39 ◽  
Author(s):  
E. Gurvich ◽  
I. Prilepskiy
Keyword(s):  
Growth Rate ◽  
Exchange Rate ◽  
Domestic Demand ◽  
Growth Trajectory ◽  
Structural Reforms ◽  
External Imbalances ◽  
Russian Economy ◽  
External Sustainability

The paper looks into emergence of external imbalances and economy’s adjustment to them. We find that Russian economy adjusts mainly via increase or decrease of domestic demand (resulting in substantial risks and losses of production), while capacity of adjustment via exchange rate channel is very limited. Another conclusion is that long-term growth rate compatible with external sustainability amounts to just 2,2%. Any attempts to boost growth above this level, not supported with profound structural reforms, would entail regular painful crises, reverting economy to the two-percentage growth trajectory.

Negative Life Events Associated With Deliberate Self-Harm in an African Population in Uganda

Crisis ◽  
2005 ◽  
Vol 26 (1) ◽  
pp. 4-11 ◽  
Author(s):  
E. Kinyanda ◽  
H. Hjelmeland ◽  
S. Musisi
Keyword(s):  
Life Events ◽  
Negative Life Events ◽  
Life Time ◽  
Later Life ◽  
Dose Effect ◽  
Deliberate Self Harm ◽  
Time Period ◽  
Significant Difference ◽  
Self Harm ◽  
Suicide Interventions

Abstract. Negative life events associated with deliberate self-harm (DSH) were investigated in an African context in Uganda. Patients admitted at three general hospitals in Kampala, Uganda were interviewed using a Luganda version (predominant language in the study area) of the European Parasuicide Study Interview Schedule I. The results of the life events and histories module are reported in this paper. The categories of negative life events in childhood that were significantly associated with DSH included those related to parents, significant others, personal events, and the total negative life events load in childhood. For the later-life time period, the negative life events load in the partner category and the total negative life events in this time period were associated with DSH. In the last-year time period, the negative life events load related to personal events and the total number of negative life events in this time period were associated with DSH. A statistically significant difference between the cases and controls for the total number of negative life events reported over the entire lifetime of the respondents was also observed, which suggests a dose effect of negative life events on DSH. Gender differences were also observed among the cases. In conclusion, life events appear to be an important factor in DSH in this cultural environment. The implication of these results for treatment and the future development of suicide interventions in this country are discussed.

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